Cannabis Grow – Page 67 – How To Grow Cannabis

The morphological modification of hemp fibers is also observed by scanning electron microscopy

The intrauterine environment is a determinant for fetal development,and any perturbation that occurs during this critical period of life can predispose individuals to later life diseases.Therefore,more studies are needed to recognize and better understand the impacts of smoking marijuana during pregnancy and its impacts on future health.These aspects and the spreading legalization of recreational use of this drug deserve critical evaluation.Hemp is one of the most productive and useful plants known for a long time,it’s used exclusively for the production of medicines,in the textile field,and also used for the preparation of the drug.However,the transformation of hemp generates a high proportion of waste.Consequently,the development of recycling processes for such wastes present a great interest to the researchers,this waste has integrated the field of composite materials as reinforcing element where he has already been used in composite materials with polypropylene,unsaturated polyester and other composites.Reinforced composites with natural fibers have attracted recently more attention in order to take advantage of their low cost,low density,biodegradability and availability,ease of implementation,their high specific modulus,and ability to be recycled ,etc.These benefits are of interest for applications in various fields such as daily life,automotive …,which require lightweight materials with high performance,opportunities for retraining,the minimum impact on the environment,and reduce the cost of the material.The most serious concerned problem with natural fibers is its hydrophilic nature because they are composed of lignocellulose,cannabis grow facility which contains hydroxyl groups.These fibers are therefore incompatible with hydrophobic thermoplastics,such as polyolefin and have low moisture resistance.

These characteristics are weak points for the uses of vegetable fibers as polymer reinforcements.It is then necessary to improve them so as to avoid penalizing mechanical properties.Another important factor is the dispersion of the fibers for obtaining high mechanical properties.These problems are the main limitations to the use of such fibers as reinforcement in polymers.Thus the matrix fiber interface makes it possible to predict the physicochemical properties of the composite materials; a force applied directly to the matrix on the surface of a composite,is transferred to the nearest fiber and propagates through the fiber at the interface.Incompatible interface,leads to inhomogeneous distribution of the forces which disrupts the mechanical properties of the composites.By cons,a good interface can allow the composite has the ability to withstand stress,even after several fibers are cut because the force can be transferred to non-broken fibers.Several studies have studied the changes cellulose fiber surface properties to enhance their adhesion with a polymer matrix and reduce moisture absorption.It has been shown that an appropriate treatment applied to the fibers may result in compatibility with the polymer matrix,which improves the quality of the composites.Various methods such as plasma treatment,alkali,heat,graft copolymerization,treatment with silane or with other chemicals have improved the compatibility of the fibers with the matrix.It is therefore essential to know the chemical surface interactions between the different constituents of the composites before performing a mechanical characterization of the whole.The main objective of this paper is to study the effect of hemp fibers treatment on their individual properties and their interfacial properties when are mixed with the polyurethane matrix.the improvement of interfacial properties of hemp fibers with the polyurethane matrix,contribute to increasing the composite material properties,the choice of the hemp fibers and the matrix is due to their thermal characteristics tested in this study,this incorporation allows the manufacture of a biodegradable composite insulation.The effect of alkali treatment at different concentration on hemp fibers is shown in the Fig.1a; it is observed that the treatment does not affect the cellulosic structure since characteristic bands of cellulose appear in the same wave number.

The small band due to the C-H bending and C-O stretching of hemicellulose was shifted to a higher wave number indicating the removal of hemicellulose at the surface after treatment.The C-H stretching in aromatic methoxyl group and methylene group of lignin structure begins to disappear while increasing the percentage of NaOH in the solution.Increasing the percentage of NaOH in the solution leads to the removal of an amount of hemicellulose and lignin from the fiber surface,NaOH treatments dissolved a portion of hemicellulose and lignin constituents from the fibers which increases the amount of cellulose exposed on the fiber surface,thereby increasing the number of reaction sites.The FTIR spectra of the fibers treated with silane solution after alkali treatment were presented in Fig.1b It can be observed the appearance of a new absorption bands in the region from 800 to 1800 cm−1,and these are specific to the silane coupling agents.The band at 1203 cm−1 is assigned to the vibrations of Si O-cellulose,indicating that the prehydrolyzed silane has reacted with the hydroxyl groups on the fiber surface.The observed band at 709–780 cm−1,caused by the vibrations of Si O-linkages,indicates that the prehydrolyzed silane has led to self-condensation reactions,giving rise to a siloxane polymer.These results demonstrate that several reactions take place between the silane coupling agents and the fiber surface during the treatment.This is in agreement with the results reported in the literature.Fig.2 shows images obtained on untreated and treated fibers.It can be seen that the untreated fibers have more compounds at the surface.The surface of untreated fibers is covered with fats,waxes or polysaccharides such as the lignin,hemicelluloses or pectins and therefore much rougher.This indicated that hemp fiber structure consists of cellulose microfibrils covered with hemicellulose and lignin.From these micro-graphs it can be seen that the cellulosic fiber surface was covered by non-cellulosic constitute.The treated fibers have a smaller diameter than the untreated fibers and their surface roughness is reduced due to the partial dissolution of the amorphous portions of the fibers.More the percentage treatment increases the fiber surface becomes depleted of non-cellulosic material.

The shows a change in the appearance of the fiber surface which may be due to the formation of silane-coupling agent on the surface of hemp fibers,the fiber surface was completely covered which confirmed the time required to achieve the equilibrium adsorption respected.Natural fibers are semi-crystalline materials composed generally of an amorphous part basically consisting of the macromolecules of lignin and hemicellulose and a crystalline portion of cellulose.The X-ray diffractograms of treated and untreated hemp fibers are indicated in Fig.3,they show the presence of peaks characteristic to cellulose molecule located at,15.2° and 16.6°,correspond respectively to the crystallographic plans 002,101 and 101.The measuring crystallinity index by Segal method presented in Table 1 reveals an improvement of crystallinity rate when the treatment percentage increase,which suggests that the alkali treatment removes non crystalline portion of the fiber increasing the percentage of cellulose in the fiber,this improvement has been observed up to 8% of NaOH treatment,after we have seen a decrease in the crystallinity index,this may be caused by the increased concentration of NaOH affecting the cellulose structure.Other study entrusted the increasing of crystallinity index after the alkaline treatment to the change of the crystalline structure of the cellulose.Studies have shown that Na + has a favourable diameter and is capable to expanding the space between the lattice planes.This leads to the formation of a network cellulose-Na-I,with relatively large distances between the cellulose molecules.The created spaces are filled with water molecules.In this structure,the -OH groups of the cellulose are converted to -ONa groups,widening the dimensions of the molecules.Subsequent washings with water will remove the Na ions bonds and convert the cellulose into a new crystalline structure of cellulose II.Sodium hydroxide allows for complete processing of the cellulose network I cellulose II with a higher crystallinity index.The resistance of the natural fibers is affected by many factors,the high molecular weight of cellulose chains,the crystal structure of the fibers and the microfibrillar angle are the most influences parameters of the mechanical properties of plant fibers.Fig.4a and b show the tensile strength and Young’s modulus respectively of untreated and alkali hemp fibers it can be seen that the treatment increase tensile strength and young’s modulus,this augmentation is observed up to 8% of treatment after this percentage,it is noticed the decrease in mechanical properties of hemp fiber.The increase in mechanical properties is mainly due to the partial removal of hemicellulose and lignin which causes the increase in the crystallinity index of the fibers and therefore the fibers becomes more rigid.The elimination of a certain amount of lignin and hemicellulose allows the relaxation of the microfibrils and their reorganization along the principal axis of the fiber giving rise to a more rigid structure,cannabis grow system the increase in the percentage of NaOH eliminates over amount of lignin and hemicellulose which will create more space empty that the microfibrils reorganizes.

Progressive augmentation of concentration in sodium hydroxide can damage the crystalline structure of the cellulose and therefore has a negative effect on the mechanical properties of the fiber which was observed at 10% of treatment.This behavior has been observed in previous works.The progressive increase in the crystal index of the fibers allows the improvement of the mechanical properties of the fibers,which can increase the mechanical properties of the composite materials after their insertion in a polymer matrix.The alkaline treatment leads to the elimination of a certain amount of impurity and wax on the surface of the hemp fibers which increases the diameter as well as the number of pores on the surface of the fibers and consequently the thermal conductivity increases.The increases of the treatment concentration are accompanied by the increase of the thermal conductivity it has been noticed in another work dealing with oil-palm fibers.The alkali treatment led to a small increase in the value of the thermal conductivity of 13% and 15% for the alkali fibers at 5% and 8% successively after these percentages we notice a strong increase of 24%.Fig.6 show the thermal conductivity of the hemp fibers measured at three temperatures.As the temperature increases,the thermal conductivity of the samples increases because in this case the vibration of the phonons is the thermal carrier and the moisture in the natural fiber begins to evaporate and escapes from the sample.In view of the results obtained,the hemp fibers have a very good conductivity.They can then be used as insulation in cold production or preservation systems in particular compared to polyurethane and polystyrene foam or glass wool which has an average conductivity of 40 mW/m.K.Several experimental techniques are used to predict the mechanical behavior of the fibers after their insertion in composite materials,the fragmentation test,the micro-bond test the push-out test and the pull-out test.These techniques make it possible to calculate the interfacial shear stress IFSS by measuring the maximum force exerted on the fiber in order to extract it from the composite material.Fig.7 shows that pull the fibers from the polyurethane matrix are carried out in three steep.Firstly,the force evolves non-linearly,or it is carried directly by the matrix and transferred from the matrix to the fiber by the fibermatrix interface,during the second stage,the force reaches its maximum and then begins to decrease,this is due to less interpenetration between the matrix and the surface of the fiber,indicating a release of stored energy.This reduction in the tensile force is triggered by the extraction of the fibers from the matrix which takes place after the fracture of the adhesive at the fiber-matrix interface,which makes the fiber detached and starts to slide.Tobacco smoke can cause numerous health related issues.While cigarette smoking is associated with the development of certain respiratory diseases,the causal link between the onset of asthma and smoking has not been established.To date,studies that examined the association between cigarette smoking and incident asthma have shown mixed results.Previous work on the topic has reported an increased risk for adults and adolescents but others reported no statistically significant associations.Although what causes the onset of asthma is still relatively unknown,experts in the field have reported that cigarette smoking or exposure to second hand smoke can certainly trigger asthma symptoms and severity.Overall cigarette smoking or second hand smoke can relate to many long term respiratory health issues,but it can also inflfluence more immediate issues for people with asthma including increased coughing and airway inflammation.For adults in California,cigarette smoking was associated with asthma severity,worse asthma-specific quality of life and greater hospitalization for asthma.Furthermore,active cigarette smoking for people with asthma can lead to accelerated loss of lung function and a decreased response to corticosteroids over time.In the past,studies on smoking behaviour in adolescents was focused on cigarette use; however,more recently other types of smoking such as water pipes,marijuana or now electronic cigarettes have emerged as a concern.

A recent toxicogenomic study conducted in our laboratory compared three different cigarette smoke condensates

It should be noted that the mycelium specimen under 98 % RH reached the maximum mass gain around the seventh day in the sorption test, and after that underwent mass loss and showed signs of mould growth on the surface. As a result, maximum mass gain instead of equilibrium mass is used to calculate the equilibrium moisture content at 98 % RH as shown in Fig. 6. The equilibrium moisture content under the desorption process is only slightly higher than the adsorption process, and no significant variation between both curves for all samples. Thermogravimetric analysis of the samples is shown in Fig. 9. All four samples are thermally stable up to about 200 ◦C, and thereafter start to decompose and reach their maximum rate of weight loss between 300 and 350 ◦C. It is, therefore, necessary to protect these insulation composites from fire hazards with other fire and heat resistant components, e.g. bricks, sheathing boards, etc. The decomposition process of the samples follows a similar trend, corresponding to hemicelluloses being pyrolyzed in the range of 200 and 300 ◦C, depolymerized cellulose in the range of 300 and 350 ◦C, lignin components pyrolyzed in the range of 225 and 450 ◦C. For cork composite, depolymerization of suberin appears between 400 and 500 ◦C. The second peak at 400 ◦C is also observed on the grass composite, contributed by other recycled materials mixed in the composite. Likewise, a similar small peak can be noticed for the hemp composite where recycled materials are also used. All composites end their volatile emissions at around 450 ◦C with a remaining char residue of around 20 to 30 % of the original dry weight. Based on the thermal conductivity findings in Fig. 7, the insulation thickness for both wall types and all four studied insulation materials are formulated to achieve an overall R-value of 4.7 K⋅m2⋅W− 1 as per the Dutch requirement for an exterior wall in a residential building, or equivalent to a U-value of 0.205 W⋅m− 2⋅K− 1. The thicknesses are listed in Table 4,cannabis grow system and it can be seen that all four materials require a higher wall thickness in comparison to reference Cellulose insulation material.

The transient thermal transmittance U-value of the investigated insulation materials under two different wall types and six different climates are investigated and summarized in Fig. 10. Only transient Uvalues in the ‘heating period’ from October to March are included as the U-value under warmer months will yield non-sensible results and is not of interest in this study. In general, all four insulation materials display matching trends of transient U-value under a combination of the same climate and wall type, however, diverge significantly when compared across different climates or wall types of the same material. Under continental climate Dfa , Dfb and Dfc , the insulated walls provide uniform thermal insulation performance close to the designed U-value at 0.205 W⋅m− 2⋅K− 1 in the heating period. Higher transient Uvalues however are observed on the walls under temperate climates Cfa , Cfb and Cfc , coincide with their milder and wetter climate profiles. On the whole, the insulated timber frame walls perform better than the brick walls, in particular under temperature climates, when a similar initial designed U-value is set for all cases. This is a consequence of the thicker and denser brick layers which hamper the moisture transport in the wall assemblies, causing higher moisture accumulation in the insulation material. This pattern reaffirms the central role of exterior climates and type of building envelop design in the evaluation of building insulation performance, when a similar category of insulation materials are to be considered, in this case, the bio-based insulation materials. If without considering durability aspects from potential deterioration due to mould growth under a humid environment, or no concern of overall wall thickness owing to the thickness of insulation layer required for the intended U-value, there is no specific material to be recommended based on their transient U-value performance. However, when the wall thickness is of interest, the cork composite with its less demanding thickness requirement is the preferred selection compared to other investigated bio-based materials, followed by the grass composites. The equilibrium moisture content in the investigated bio-based insulation composites under two different wall types and six different climates in a simulated year is shown in Fig. 11.

Mycelium composite shows the highest moisture content under all climates and wall types, while cork composite shows the lowest and the most regulated moisture content throughout the year in general. Both grass and hemp composites exhibit similar moisture content to the reference cellulose insulation material. These dynamic moisture content of the composites are in agreement with their sorption isotherm, i.e. higher sorption capacity of mycelium composite and the opposite for cork composite. Higher moisture content in an insulation layer can be found at the near-interfaced layers, in the case of the selected wall type and climates, they are either at layers next to the exterior sheathing board or behind the interior sheathing board.A few observations can be generalized based on the climate types: for Cfa and Dfa , moisture tends to accumulate at the exterior interface during the winter period and interior interface during the summer period; for Cfb , Dfb and Dfc , moisture accumulation is generally found on the exterior interface during the winter period, and while the moisture content is increasing on the interior interface during summertime it is still not exceeding that of the exterior side; and for Cfc , the moisture content at the exterior interface is always higher than the interior interface. It can be established that the insulation layer at the exterior interface has the highest averaged moisture content under all six climates, and consequently is most likely subjected to mould growth and degradation compared to other parts of insulation under different climate conditions. In terms of wall type, insulation material inside the timber frame walls have generally lower moisture content at the exterior interface than those inside brick walls across different climates except Dfc. The opposite trend is observed at the interior interface where the insulation layer in timber frame walls has higher moisture content compared to brick walls. Note that no vapour retarder is included in the design of all simulated walls to retard the vapour diffusion process, and a ventilated air cavity is included in all cases to provide additional hygrothermal regulation to the overall wall assembly. After exposing the test specimen for four weeks to high humidity in a desiccator filled with water, the specimen is visually inspected with the naked eye and microscope for the presence of mould. Fig. 13 shows photos taken on the specimen with and without high humidity conditioning. The fungal growth on the test specimen is assessed according to ISO 846 and the intensity scales of mould growth are assigned to them in Table 5. Note that mould growth was already observed on mycelium composite conditioned under 98 % RH in the sorption test, as discussed in section 3.1.

Discolouring on the hemp composite can be perceived with naked eyes and fungi are distinguished easily under a microscope. For the grass composite, no obvious mould growth or discolouring is observed with the naked eye, however, deterioration of the fibres is noticeable under the microscope. No apparent deterioration, mould growth or discolouring is detected on the cork composite. These results are in agreement with the literature: similar mould development can be distinguished with the naked eye on the mycelium-miscanthus test sample by Dias et al.; fungi contamination can be observed under a microscope on hemp shiv composites by Viel et al.; on the other hand mould development on grass and cork composite is not presented on the literature. Marijuana smoke is a complex mixture composed of thousands of chemical compounds,many of which are qualitatively similar to those found in tobacco smoke.Like tobacco smoke,marijuana smoke has been associated with numerous adverse pulmonary effects in humans including airway inflammation,chronic bronchitis,edema,mucus hypersecretion,and the impairment of large airway function and lung efficiency.Moreover,Aldington et al.showed that the impairment of large airway function and lung efficiency is 2.5–5 times greater in marijuana smokers than tobacco smokers.Like tobacco smoke,previous studies have also shown marijuana smoke to be genotoxic both in vitro and in vivo.In addition,it is suspected that marijuana smoke may be carcinogenic.Indeed,some agencies such as the California Environmental Protection Agency have placed marijuana smoke on their list of chemicals known to cause cancer.However,since there is a paucity of marijuana-only smoking populations to complete definitive studies,epidemiological studies conducted to date are limited in scope,and often confounded by concurrent tobacco smoking.Therefore,a clear and widely accepted empirical link between marijuana smoking and cancer does not exist.Information on the pharmacokinetics of marijuana smoke,and the mechanisms by which it may cause adverse effects,is also limited.Several mechanisms have been proposed including genotoxicity,alterations in endocrine function,alterations in cell signaling pathways,marijuana grow system and immune suppression.However,many of these findings are based on the testing of individual cannabinoids found in marijuana smoke,as opposed to the whole smoke or smoke condensate.

Genome-wide expression profiling may provide information to permit a better understanding of the toxicological pathways perturbed by exposure to marijuana smoke.Currently,there are no published studies that have used a whole genome toxicogenomics approach to evaluate responses to marijuana smoke.However,Sarafifian et al.employed a targeted stress response gene expression array to evaluate the effects of 9-tetrahydrocannabinol,the main psychoactive component of marijuana,on human small airway epithelial cells.They observed significant changes in genes related to xenobiotic metabolism,DNA damage response,inflammation and apoptosis.micro-array technology has been used more extensively to evaluate gene expression changes following exposure to tobacco smoke.For example,Sen et al.reviewed 28 studies examining transcriptional responses to complex mixtures including whole cigarette smoke and cigarette smoke condensate,and included in vivo and in vitro studies using human and rodent tissues.It was determined that the pathways most frequently affected by tobacco smoke were oxidative stress response,xenobiotic metabolism,inflammation/immune response,and matrix degradation.Other micro-array studies have noted a DNA damage response leading to cell cycle arrest and apoptosis to be among the top pathways affected by tobacco smoke.The results of this study showed extensive overlap with the affected pathways highlighted in the review by Sen et al..Our study also showed that gene expression is remarkably similar across cigarette brands,and there is limited variation in the genotoxic potency of cigarette smoke condensates.In contrast to these findings,our earlier work revealed that tobacco and marijuana smoke condensates differ substantially in terms of their genotoxicity.More specifically,MSC were observed to be significantly more cytotoxic and mutagenic than matched tobacco smoke condensates.In addition,TSC appeared to induce chromosomal damage in a concentration-dependent manner,whereas matched marijuana condensates did not.The mechanisms underlying these differences in toxicity are unclear and warrant further investigation.As an extension of our previous work,the objective of the present study is to employ a toxicogenomics approach to compare and contrast the molecular pathways that are perturbed by MSC and TSC.A murine pulmonary epithelial cell line was employed for in vitro exposures to both MSC and TSC.The results show that the pathways perturbed by MSC as compared to TSC are largely similar.However,subtle differences in gene expression provide insight into mechanisms underlying the observed differences in toxicities.The tobacco samples consisted of a popular Canadian brand of fine-cut tobacco obtained from a local retail store.The cigarettes contain Virginia flue-cured tobacco,which is distinct from the mixed tobacco blends typically found in American cigarettes.The cannabis samples consisted of a standardized product,grown under strictly controlled and documented conditions.The product was obtained from Prairie Plant Systems Inc.,and all samples were from harvest #55.Upon harvest,flowering heads were dried to a moisture content of approximately 10%,milled to 10 mm,packaged and irradiated.The preparation and combustion of the cannabis and tobacco cigarettes was conducted by Labstat International Inc.as described previously.Briefly,samples of marijuana and tobacco were laid out on aluminum trays and conditioned at a temperature of 22 ◦C and a relative humidity of 60% for 48 h.775 mg of each product was transferred to a cigarette-rolling device,and cigarettes were prepared using commercially available cigarette papers,all without filters.All cigarettes were stored in sealed plastic bags until combustion.Samples were removed from the bags and conditioned for a minimum of 48 h prior to smoking,as required by ISO 3402:1999.The cigarettes were smoked according to a modified smoking regime intended to reflect marijuana smoking behavior.

Maternal cigarette smoking is typically considered to be a risk factor for SPTB and SGA

Data from this analysis were obtained from the SCreening for Pregnancy Endpoints study, which aimed to build a clinical database and pregnancy bio-bank to screen candidate markers of pregnancy complications. The SCOPE study recruited nulliparous women with singleton pregnancies between November 2004 and February 2011 from one centre in each of Australia, New Zealand, and Ireland, and three centres in the United Kingdom. Ethical approval was obtained from local ethics committees [New Zealand AKX/02/00/364, Australia REC 1712/5/2008, London, Leeds and Manchester 06/MRE01/98 and Cork ECM5 05/02/08] and all women provided written informed consent. Women were invited to participate prior to 15 weeks’ gestation when attending hospital antenatal clinics, obstetricians, general practitioners or community midwives, and were interviewed and examined by a research midwife at 15 ± 1 and 20 ± 1 weeks of gestation. The exclusion criteria included women who were considered to be at high risk of PE, SGA or PTB due to underlying medical conditions , previous cervical knife cone biopsy, three terminations or three miscarriages or if their pregnancy was complicated by a known major fetal anomaly or abnormal karyotype, or if they received interventions that may modify pregnancy outcome. Details of maternal age, BMI and socioeconomic index1, medical and family history, along with dietary and lifestyle questionnaires with self-reported marijuana and cigarette smoking were recorded at 15 weeks’ and 20 weeks’ gestation and entered into an internet-accessed, password-protected centralised database with a complete audit trail. The number of episodes of marijuana use over 3 months was also recorded at 15 weeks and 20 weeks of gestation. Other drug use was also recorded, including cocaine, amphetamines, substance 1 a scale between 10 and 90 generated using an algorithm involving age, income and education. A higher score indicates higher socioeconomic status. It is a validated measure of individual socioeconomic status. P, Ecstasy, opiates, and hallucinogens, with less than 0.6% of women who have taken these drugs 3 months prior to or during pregnancy in SCOPE, but there were insufficient data to be included for analysis.

Self- reported marijuana and cigarette smoking status were classified into five categories in univariable and multi-variable analysis,hydro tray with ‘non-smoking’ or ‘never used marijuana’ as the reference categories. The number of reported episodes of marijuana use was included as a continuous variable for frequency effect estimation. Use was self-reported where women provided the number of joints or cones used. Spontaneous preterm birth was defined as birth at less than 37 weeks of gestation that was not a result of medical or obstetric intervention. Small for gestational age was defined as a birthweight of less than the 10th customised centile, adjusted for maternal height, weight, parity, ethnicity, gestational age at delivery and infant sex. Preeclampsia was defined as gestational hypertension accompanied by proteinuria. Gestational diabetes mellitus was defined as a fasting glucose of 5.5 mmol/L or higher in a Glucose Tolerance Test, a 2 h level of 8 mmol or higher, or a random glucose level of 11 nmol/L or higher. Universal screening was not employed for GDM in the UK and Ireland, where only women identified at risk based on factors such as family history and BMI were screened.A total of 5588 participants were included in the analysis, with 1155participants recruited from Australia, 2014 from New Zealand, 1765 from Ireland, and 654 from the United Kingdom. Within the 1514 pregnancies with complications, 278 had PE, 633 had SGA, 236 had SPTB, 470 had GHT, and 143 had GDM. Details on age, BMI, SEI, as well as marijuana use and cigarette smoking status were complete for all participants. Marijuana and cigarette smoking status were compared between non-cases and each of the outcomes separately using Fisher’s exact test. Although about 4% of women had more than one pregnancy complication, each outcome was analysed separately compared with non-cases. Continuous factors, including maternal age, BMI and SEI were compared using Student’s t-test. To investigate the effects of marijuana use between smokers and non-smokers, analysis of marijuana use, stratified by cigarette smoking status for each outcome was performed. Breslow-Day test was used to assess the homogeneity of the odds of marijuana use between cigarette smokers and non-smokers, along with an adjusted common odds estimated from Mantel-Haenszel test.

Marijuana and cigarette smoking status were then analysed with mixed effects logistic regression to determine the association with pregnancy outcomes, adjusting for maternal age, BMI and SEI, and with recruiting centre differences accounted for as a random effect. Interaction tests were also performed by comparing logistic regression models that included interaction terms. A linear mixed model was also fitted for length of gestation, with quadratic terms for the number of times marijuana was used over the preceding 3 months at 15 and 20 weeks of gestation, age, and BMI, to investigate the dose effect of marijuana and cigarette smoking status on the length of gestation adjusted for other factors in the model. The estimated power of this analysis, involving logistic regression with interaction terms, is 0.99. All statistical analyses were performed using R version 3.2.0.It was important to determine whether the association with marijuana use was due to concomitant cigarette smoking. Breslow Day test showed no evidence of heterogeneity in the association of marijuana use and pregnancy outcomes between smokers and nonsmokers , which indicates that the association between marijuana and SPTB was consistent regardless of cigarette smoking status. Hence, when comparing any marijuana use, three months prior to or during pregnancy, between cigarette smokers and non-smokers, there was a significant independent association between any marijuana use and SPTB. While the association between marijuana use and SPTB was independent of smoking status, the Mantel-Haenszel test further indicated that the overall association was also significant , with an adjusted common odds of 2.28. That is, the odds of SPTB for any marijuana use three months prior to or during pregnancy was more than doubled for both cigarette smokers and non-smokers. Regarding the interaction effect of marijuana in women who ceased cigarette smoking during pregnancy, results from Breslow Day test on the homogeneity of the odds of any marijuana use , between women who continued cigarette smoking before 20 weeks’ gestation and those who stopped smoking, showed no evidence of heterogeneity,with a Mantel-Haenszel adjusted odds of 1.97. This indicated that the effect of marijuana use was not only independent of any cigarette smoking three months prior to or during pregnancy , but was also consistent, with nearly doubled odds, irrespective of whether cigarette smoking ceased prior to 20 weeks’ gestation.

Results from Logistic regression with an interaction term between marijuana use and cigarette smoking status also showed no significant interaction effects on SPTB.The results from linear mixed modelling showed that marijuana use in first or second trimester had significant effects on length of gestation, when adjusted for age, BMI, SEI, cigarette smoking status, and alcohol consumption. The predicted length of gestation was lower for women who continued to use marijuana at 20 weeks of gestation for both cigarette smokers and non-smokers, with an estimated gestation of less than 37 weeks when more than 100 episodes of marijuana use within the previous three months before 20 weeks’ gestation. It should be noted that there was a small but significant decrease in the predicted length of gestation for cigarette smokers compared to non-smokers. However, our data show that continued marijuana use at 20 weeks of gestation has a greater effect on gestation irrespective of cigarette smoking status. Linear mixed modelling indicates a modest reduction in gestation in women who ceased marijuana use at 15 weeks’ gestation. However, in women who continued to use marijuana at 20 weeks’ gestation, there was a much greater decline in gestational age at delivery.Marijuana use is increasing in women of reproductive age and its continued use in pregnancy has been of concern for some time. In addition, we have anecdotal evidence to suggest that some pregnant women are using marijuana to reduce nausea in early Fig. 2. Predicted length of gestation and number of episodes of marijuana use in women who did or did not also smoke cigarettes in the previous 3 months. Note: actual range of marijuana use 0–450 episodes in 3 months. pregnancy. In this large prospective cohort of nulliparous women we have demonstrated that continued maternal use of marijuana at 20 weeks’ gestation is a major contributing risk factor for SPTB. Univariable analysis showed a significant association of marijuana use at 20 weeks’ gestation with SPTB and also SGA, but when adjusted for other factors,planting table in particular cigarette smoking, marijuana use was only a significant independent risk factor for SPTB. Furthermore, if marijuana use was continued at 20 weeks’ gestation, women were over five times more likely to deliver preterm than nonusers. Of the women who continued to use marijuana at 20 weeks’ gestation and delivered preterm, nearly 64% delivered at less than 32 weeks’ gestation. Our data do not have sufficient power to determine whether there is a gestational age prior to 20 weeks by which it is advisable to cease marijuana use. Hence, at this stage we recommend that it is prudent to abstain from marijuana use during pregnancy.

Based on the current findings and some earlier reports, it is likely that maternal marijuana use is an independent risk factor for SPTB. It has been shown that the active compound of marijuana and its metabolites are able to cross the placental barrier and thereby have the potential to directly affect perinatal outcomes. Whereas the results from this study are in agreement with other studies, it needs to be noted that a few American and a UK prospective cohort studies did not find an association between marijuana use and SPTB. However, these studies have a higher percentage of black race, whereas there are 89.9% Caucasians in this study. Although the studies have also adjusted for ethnicity, age, BMI, and other lifestyle factors, interaction tests were not performed in the analysis to examine the interaction effects of marijuana use and cigarette smoking on pregnancy outcomes.While African American ethnicity has been associated with an increased risk of SPTB, it has also been commonly associated with lower socio-economic status. The relationship of low SEI with pregnancy complications was apparent in this study, where SEI was significantly negatively associated with PE, GHT, GDM, SGA, and SPTB. When adjusted for age, BMI, cigarette smoking, and marijuana use, higher SEI was a protective factor, with a 1–2% decrease in the risk of PE per unit increase in SEI. Similar trends were also seen in previously published SCOPE data. However, the results from the current study showed no significant interaction effects between marijuana use and SEI, suggesting that the association between marijuana use and SPTB was also independent of socio-economic status. Despite a borderline significance for alcohol consumption at 15 weeks’ gestation for PE risk, our results are consistent with a study by Klonoff-Cohen et al., which showed that maternal alcohol consumption does not appear to have a significant association with preeclampsia. Alcohol consumption during first trimester was not associated with SPTB, consistent with a previous SCOPE publication. However, continued alcohol consumption at 20 weeks’ gestation is a protective factor for SPTB, and a recent study by Lundsberg et al. also showed that alcohol consumption during third trimester was associated with a decreased risk of PTB but not when consumed during early pregnancy. The mechanism of this effect is still unknown. However, as maternal alcohol consumption may damage the fetus we cannot recommend it during pregnancy and indeed the National Health and Medical Research Council Guidelines recommend against its use in pregnancy.Indeed, maternal cigarette smoking at 20 weeks’ gestation was significantly associated with risk of SPTB and SGA in univariable tests, but no longer significant for SPTB when adjusted for other factors, including BMI, SEI, age, and marijuana. Similar results have been found previously in a study by Dekker et al, which incorporated multiple novel risk factors for SPTB. In the current study an association was seen between smoking and SPTB , but cigarette smoking was not found to be an independent risk factor for SPTB after adjustment for marijuana use. Nevertheless, continued cigarette smoking is a significant risk factor for many pregnancy complications including stillbirth, placental abruption and SGA and women should be encouraged to quit before or in early pregnancy.

Marijuana use also has a role as a risk factor for myocardial infarction

Hemp is an annual herb plant which is used for production fibre for such as rope, sail and clothing as well as the seed crushed for oil, food and feed. Due to the outer portion of the hemp stem contains strong and long bast, fibre provides a strength and high quality textile, while inner of the stem so called hurd also used for paper and building material. After Thai royal project interested in developing industrial hemp as an economic crop to support the hill tribes, the quality seed are needed to propagate and disperse for the farmer. In addition, the cultivation of hemp is being permitted in Thailand especially in the north, but under strict control and monitoring by office of the narcotics control board of Thai. Hemp is determined a dioecious crop and seed production is required a wider space from plant to plant than producing as fibre. In addition as an annual crop, cultivated seed are usually sown in early March and late of May, and harvested in the end of November under preferable natural temperature 14 – 27 ºC. Therefore, they are attractive to produce exceed seed supply and then stored for one or several years for cultivation. Storage of seed is an important process of plant production to avoid unfavourable environmental conditions and the acceleration of the deteriorations, which is started after harvest. Storage conditions play an important role to maintain high seed quality, which directly related to environmental conditions. However, the sensitivity of seed to high temperature is depended on the water content that the higher moisture content, the looser viability. Seed deterioration is associated with the genotype, seed history and their physiological and chemical compositions. As in hemp, seed is determined as an orthodox seed that can be dried to low moisture content and stored at low temperature for several years. Nonetheless, the seed contain 20 – 25% protein, 20 – 30% carbohydrates, 10 – 15% insoluble fibre and especially 25 -35% oil which was considered to be the major contributors to seed deterioration as previous demonstrations of soybean , peanut and sunflower. For hemp seed, it was suggested that seed should be dried until the moisture content lower than 12%. Consequently,vertical farming for further storage, either high or low relative humidity affected the moisture equilibrium of seed due to hygroscopic property. Then, the type of container was important for protecting moisture immigration.

As in closely fibre species such as kenaf , seed stored at 8% mc remains viable for up to 5.5 years when stored at 8 ºC and stored above 10 ºC and 12% mc showed significant decrease in seed viability. In parallel, Meints and Smith, also found that germination of kenaf under ideal conditions remained high in seed stored up to 4 years at 10 ºC and did not show appreciable differences in field emergence or performance through the growing season. Determination of hemp seed qualities which were derived from segregation of the local land race would assist the Royal project and further seed supplier in reliable on fibre hemp production. The objectives of this study were to determine the impact of storage conditions and hemp seed quality losses during year storage. These experiments were conducted to compare storage condition affecting different hemp seed cultivars by observing the physiological of seed qualities. The moisture contents at which these changes are observed among cultivars, and continuously involve in the change of stored seed quality. The seed cv. RPF2 contained higher moisture content than the others and also showing lower initial germination illustrated significantly decreased with storage time when packed in both seal aluminium foil and plastic bag at ambient temperature. McDonald stated that the effect of high temperatures on seeds quality is highly dependent on their water content and the loss of viability was more rapid when the seed contain high moisture. However, the quality of seed packed in both materials was not different during 5 month, but after that aluminium foil had an adverse effect on reduction of seed viability and vigour than plastic bag during 5 – 8 month. This suggested that high moisture content seeds might be closely oppressed to dry air and then water remove to the surface because of hygroscopic of which higher moisture content was observed in seed packed in aluminium foil. The change of moisture content was not different when seed stored in aluminium foil at 15, 4 and –4 ºC, while the seed germination and vigour was also remained. The result revealed that aluminium foil has better water and oxygen proved properties than plastic bag made from polypropylene which the exchange were 0.0914/m2 /hr and 0.2472/m2 /hr for oxygen; 65 g-water/m2/hr and 1378 g-water/m2/hr for water, respectively. This suggested that initial moisture content and germination are the main factor for providing seed longevity. Hemp seed containing high moisture content stored at room temperature maintained the germination and vigour only up to 5 months of storage, after that the conditions and aging was deleterious to seed viability. Seed deterioration is associated with various biochemicals, metabolic and physiological alteration including loss of membrane integrity and cell compartmentalization, decreasing in ATP production and impairment of RNA and protein biosynthesis.

Moreover, lipid peroxidation and free radicals were considered to be the major contributors to seed deterioration , especially, at high temperature, it was mainly related to membrane damage and alteration of energy metabolisms as demonstrated in sunflower. In the other hand, seed germination and vigour of low seed moisture content as cv. RPF3 contained in aluminium foil at room temperature remained viable. This previous study mentioned that the dehydration of seed could prevent thermal denaturation. Marijuana use dates back to 2727 BC to Chinese Emperor Shen Nung. After spreading through the Greek and Roman empires and into the Islamic empire of North Africa and the Middle East, it was brought to the Western hemisphere by the Spanish. Originally lauded for its utility as fiber, it was not until its migration into North America that it began to be used in a similar fashion as it is today. Used in the form of hemp, it was seen throughout society as rope, clothing and even paper. While marijuana has been used by Americans recreationally for years, it is a subject that is becoming more commonplace in our modern society. According to the National Institutes of Health, marijuana use in 2015e2016 rose from 4.1% to 9.5% of the U.S. adult population. With more states eliminating the legal ramifications of its use and a growing debate about its federal legality, this is a subject that routinely makes local and national headlines. With a diverse array of commercial products becoming available from chocolate squares to oral sprays, marijuana is also no longer restricted to a rolled cigarette. The medical community has also joined the debate. The most obvious correlation between medicine and marijuana is medicinal marijuana. Marijuana’s effects have been well documented, allowing the push for its use as medicine within multiple specialities. Proponents of its use point to its effects on the endocannabinoid system. Studies show that through its impact on different pathways it may be used as an analgesic, immunosuppressant, muscle relaxant, anti-inflammatory agent, appetite modulator, antidepressant, antiemetic, bronchodilator, neuroleptic, antineoplastic and antiallergen. Medical marijuana also differs in chemical composition, containing a higher tetrahydrocannabinol concentration and less cannabinol than the recreational version. This is even before taking into consideration the various extraneous agents that may be found within the available recreational drug.

There is however, very little, if any research evaluating marijuana’s use in surgery. This paucity of literature presents a problem. While many surgeons may ask about recreation drug use including marijuana, many other drugs have established evidence based outcomes that allow variation in surgical planning as needed. However, when it comes to marijuana, surgeons are left to determine what to do with this information on their own.Despite the multiple studies on the physiologic effects of marijuana use, clinical studies, if any, are not cited in the medical literature. This study reviews the literature available on marijuana’s effects and discusses potential complications that may result within the surgical setting. With a reported estimation of 10%e20% of patients between the ages of 18 and 25 years regularly using marijuana, this review seeks to become an initial step for further exploration of the subject and to reveal why there is a need for more in-depth research.Due to limited research and reviews on this subject, information was utilized from articles on surgery in various fields, such as orthopedic, dental and bariatric with anesthesia considerations and general topics related to marijuana also examined. The following information was gathered: marijuana’s prevalence in the United States, marijuana’s effects on the cardiovascular system and pulmonary system, potential coagulopathies, marijuana’s effects in relation to anesthesiology, evidence based screening methods for recreational drug use, potential surgical complications that may result from marijuana use,flood tray and recommendations on marijuana use and surgery.When marijuana is smoked, THC and other cannabinoids are absorbed rapidly through the lungs with effects peaking in 15 minutes. These effects can persist for up to a dose-dependent 4 hours in the acute setting. When ingested orally however, onset of effects is slower but has a longer duration of action , due to continued absorption in the gut. This is despite a lower bioavailability due to first-pass metabolism by the liver which results in a blood concentration 25% of what is obtained if smoked. The cognitive/psychomotor effects can be present for up to 24 hours regardless of administration route. Cannabinoids are highly lipid soluble. This leads to a slow release into the bloodstream with a single dose not fully eliminated for up to 30 days. The cardiovascular effects of marijuana use range from benign to worrisome based on the timeline of use and dosage.

In a series single blind study comparing the effects of high and low doses of THC in healthy young men, tachycardia was induced beginning within the time of inhalation, and persisting at least 90 minutes, with the maximum heart rate reached at an average of 30 minutes. The study also found a significant elevation in systolic and diastolic blood pressures as well as the presence of premature ventricular contractions in subjects who received the higher doses. These experiments showed a correlation between the dose and the tachycardic and cardiovascular changes. In addition, Malit et al.’s study on the effects of intravenous THC found the majority of patients to exceed the 100 beats per minute mark but also experience intermittent spikes in heart rate with a possible etiology of psychological distress. Beaconsfield et al. postulated a mechanism of beta adrenergic stimulation for the tachycardia as he was able to block the tachycardia with the use of propranolol. Pharmacology lays credence to this. At lower or moderate doses, marijuana increases sympathetic activity reducing parasympathetics and producing an elevation in heart rate, cardiac output and blood pressure. However, the opposite is true as the dosage increases. At high doses, the parasympathetic system takes over, leading to bradycardia and hypotension with animal studies postulating that the sympathetic inhibition occurs due to the bioactive constituent of cannabis’s effects on the CB1 receptors. In addition to sinus tachycardia, marijuana use has been linked to multiple electrocardiogram changes in various case reports. Daccarrett et al. found Brugadalike changes in a 19 year old male with a known history of cannabis use and no anatomical/functional abnormalities. A case was also reported in which cannabis use was linked to the development of atrial flutter and atrial fibrillation, while other studies have reported the presence of sinus bradycardia and AV block.Aronow et al., found that while comparing marijuana to placebo, cannabis causes an increase in carboxyhemoglobin, a resultant increase in myocardial oxygen demand, decrease in oxygen supply as well as an induction of platelet aggregation. One case report showed a 21 year old male who presented with a ST elevation myocardial infarction due to plaque rupture as a complication of marijuana use. In Mittleman et al.’s analysis of over 3,800 cases of myocardial infarction, 124 patients reported use within the last year of which 37 reported use within 24 hours, with 9 reporting use within an hour of the event. The study found a statistically significant 4.8 fold increase in myocardial infarction within the first hour of marijuana use. In fact, as THC content of marijuana increases, there are a growing number of clinical studies demonstrating the association between cannabis use and adverse cardiovascular events. One such study followed 1913 adults prospectively and demonstrated that in patients with prior myocardial infarction, marijuana use up to once per week increased risk of death 2.5 fold while more frequent use yielded a fourfold risk of dying.

A handful of previous studies have suggested that subjective experiences for different drugs may share a common etiology

Tashkin et al measured FEV1 serially in 255 habitual male and female smokers of marijuana and/or tobacco and nonsmokers of either substance on up to seven occasions at intervals of $ 1 year over a total period of up to 8 years. Random effects models were used in men and women separately to estimate mean rates of decline in FEV1 and to compare these rates between smokers of marijuana or tobacco alone, smokers of both substances, and nonsmokers of either substance. Smoking marijuana was not found to be associated with greater declines in FEV1 than nonsmoking nor was a relationship seen between the daily number of marijuana joints smoked and rate of decline in FEV1. In contrast, smoking tobacco had a significant effect on FEV1 decline in men in a dose-responsive manner. Findings are illustrated in Figure 3. Hancox et al performed serial lung function measurements in 779 members of a birth cohort in Dunedin, New Zealand, at 18, 21, 26, and 32 years of age. They assessed changes in FEV1, FVC, and FEV1/FVC associated with tobacco and marijuana smoking using regression analyses and estimates of both joint-years and pack-years as predictors, adjusting for sex and height at 32 years of age, changes in height between 15 and 32 years of age, and concomitant tobacco or marijuana use. The results are shown in Table 3. Among marijuana smokers, FVC increased significantly over time, whereasFEV1 showed a non significant increase and FEV1/FVC exhibited a non significant decline. In contrast, among tobacco smokers, FEV1 and FEV1/FVC both showed significant declines, whereas FVC showed no change.The smoke contents of marijuana cigarettes contain the same procarcinogenic components, including the very potent human carcinogen, benzpyrene, found in tobacco smoke.Bronchial biopsies obtained from heavy, habitual marijuana smokers have shown the same widespread histopathologic epithelial abnormalities noted in tobacco smokers, including squamous metaplasia and cellular disorganization,that are widely thought to be precancerous.

Immunohistologic examination of bronchial biopsies from marijuana smokers has shown higher levels of the protein products of oncogenes, including Ki67 and EGFR,whereas laryngeal cancer specimens from marijuana smokers have been shown to exhibit increased expression of oncoproteins compared both with tobacco smokers and nonsmokers.A few older epidemiologic studies from North Africa have shown a positive association with lung cancer; however,greenhouse rolling racks the common practice of admixing marijuana and tobacco within the same cigarette in these societies precludes disentangling the effects of marijuana from those of tobacco. A population-based cohort study of men 18 to 20 years of age conscripted into the Swedish military in 1969 to 1970 tracked these men until 2009 for incident lung cancer cases using linked nationwide medical registries.Cox regression was used to assess the relationship between lifetime use of marijuana self-reported at the time of conscription and risk of subsequent lung cancer diagnosis over the ensuring 40 years, adjusting for tobacco use also up to only 18 to 20 years of age.The hazard ratio for lung cancer was significantly positive in relation to lifetime marijuana use of > 50 times. However, because neither marijuana nor tobacco use was determined after the baseline assessment, the authors were unable to adjust for true lifetime use of tobacco, a crucially important residual confounder.Several investigators have demonstrated a tumor suppressive effect of THC and other cannabinoids on a variety of malignancies, including lung, in both cell culture systems and animal models, as previously reviewed by Bifulco et al and Velasco et al.These findings appear to reflect antiproliferative, proapoptotic, and antiangiogenic properties of THC that might counteract the tumor-initiating or tumorpromoting effects of the carcinogens contained with the smoke of marijuana. A large cohort study of health plan participants in Northern California failed to show an increased risk of tobacco-related cancers in association with self-reported marijuana use.A pooled analysis of six well-designed case-control studies of the association between habitual marijuana smoking and lung cancer that totaled 2,159 cases and 2,985 control subjects did not find any increased risk of lung cancer in association with marijuana use.Only one of the six studies included in the pooled analysis showed a significantly positive association between lung cancer and marijuana use, mainly in the heaviest marijuana use tertile, but the latter tertile included only four matched control subjects, making the estimates of risk imprecise.

Marijuana smoking might predispose to lower respiratory tract infection in at least three ways. First, the destruction of ciliated epithelium in the large central airways and the associated hyperplasia of mucus-secreting surface epithelial cells demonstrated in bronchial biopsies of habitual marijuana smokers may lead to increased production of mucus in the face of a diminished capacity to cleanse the lung of the excess mucus because of ciliary loss, thereby providing a substrate for potentially pathogenic microbial organisms colonizing the lower respiratory tract.Second, the immunosuppressive effect of THC leading to impairment of the bactericidal and fungicidal activity of AMs,further compromises the lung’s defense against microbial infection. Finally, marijuana has been shown to be frequently contaminated with Aspergillus fumigatus and potentially pathogenic gram-negative bacteria.Therefore, introduction of these microorganisms into the lung in the face of marijuana-related impairment in the lung’s host defense provides another possible mechanism for increasing the risk of pneumonia. The possible association of marijuana with an increased risk of pneumonia is supported by older case reports of Aspergillus pneumonia in smokers of marijuana immunocompromised by AIDS,chronic granulomatous disease,bone marrow transplantation,renal transplantation, or lung cancer treated with chemotherapy.In addition, a cluster of five patients with cavitary TB who used a marijuana water pipe was reported in Australia in 2003, followed by another report from Australia 10 years later of three additional cases of open cavitary TB in marijuana bong users.In these cases, it is not clear whether the spread of TB infection was because of close contact with patients with cavitary TB who might have shared a water pipe to smoke marijuana and/or to marijuana-related impairment in the lung’s defense against infection. Although a few older epidemiologic studies have suggested that marijuana use might be a significant independent risk factor for opportunistic infection in individuals who are HIV positive,an early analysis of data from the Multi-center AIDS Cohort Study failed to find evidence that marijuana was a risk factor for progression of individuals who are HIV positive to full-blown AIDS.Further preliminary analysis of the possible association of marijuana use with pneumonia risk using the Multi-center AIDS Cohort Study data set updated to 2013 has not shown a significant association of marijuana use with increased risk of either community-acquired or opportunistic pneumonia in either the HIV-negative or HIV-positive members of the cohort, after adjustment for tobacco, age, and among the individuals who are HIV positive, cluster of differentiation 4 cell counts and viral load.

A long-standing observation in clinical and epidemiological research into substance use has been that users of one drug typically do not limit their use to a single substance. For example, alcohol and tobacco are commonly used by the same person and often in the same setting, as are tobacco and marijuana. Though the synergistic effects of these particular drugs have been suggested as a potential explanation , another interesting possibility is that individuals have an underlying liability to drug use within and across different pharmacological classes. Support for this notion has been shown for both licit and illicit drugs in a variety of populations and drug use phenotypes. As poly-substance use is associated with problematic use and reduced treatment efficacy , identifying informative precursors to the onset of abuse and dependence remains a priority. Among the variety of factors that have been examined as an early indicator of later, more problematic use patterns, how someone experiences a drug , is one of the most interesting. Subjective experiences are thought to reflect individual differences in the pharmacological effects of a drug. Factor analytic studies of these experiences frequently yield two main factors: pleasant or positive and unpleasant or negative. Positive subjective experiences often include euphoria, relaxation, and feeling less inhibition. Negative subjective experiences include nausea,vertical grow difficulty inhaling, dizziness and sadness. Though weakly correlated , users of a drug sometimes report both positive and negative experiences. Alcohol, tobacco, and marijuana are the most commonly used licit and illicit drugs. Studies examining the subjective experiences to these drugs have generally found that how a person responds to a particular drug is predictive of more problematic use of the same drug. For example, dependent cigarette users more frequently endorse positive experiences than regular smokers and moderate-to-heavy drinkers report experiencing greater stimulant-like effects to alcohol than lighter drinkers. A similar relationship has been demonstrated for marijuana use. Although results are mixed, negative experiences to tobacco and marijuana have also been positively associated with problematic use. For alcohol consumption, low levels of response, primarily measured using negative subjective effects, have been associated with an increased risk of an alcohol use disorder as lower thresholds to the sedative effects of alcohol protected against developing abuse later in life.In particular, subjective experiences to a variety of drugs are correlated and can predict levels of involvement for substances in other pharmacological classes. This observation has been shown for pleasurable experiences of alcohol and tobacco where both drugs were predictive of current alcohol use in a college aged sample. Further, marijuana use has been shown to increase a sense of “liking” among non-smokers whereas alcohol has no effect on the subjective experiences of cigarettes. Lastly, greater rates of alcohol dependence and illicit drug use have been observed among high marijuana users as defined by greater rates of sensitivity to positive and negative subjective experiences. Though additional studies are needed, these cross-drug results indicate that how a person responds to a drug is predictive of how they will respond to other drugs. In this report we detail findings from a study of subjective experiences to alcohol, tobacco, and marijuana in a sample of young adults participating in the Colorado Center for Antisocial Drug Dependence. Subjective experiences were collected from both clinical and community participants using a questionnaire developed by Lyons et al.. Our analyses were designed to address three questions. First, how do positive and negative subjective experiences across alcohol, tobacco, and marijuana compare? Second, to what extent do subjective experiences to alcohol,tobacco, and marijuana overlap? Lastly, to what degree do subjective experiences to one drug associate with more problematic use behaviors for a different drug?Participants were drawn from the Colorado Center on Antisocial Drug Dependence [CADD] and consisted of 3853 participants between the ages of 11 and 30 years old and included both community and clinical participants. Our community-based sample was drawn from those participating in the Colorado Twin Registry , Colorado Adoption Project , with clinical controls drawn from the Colorado Adolescent Substance Abuse Family Study. Our clinical sample was drawn from adolescents in treatment for substance abuse and delinquency as a part of the ASA study. Additional clinical participants were drawn from an adjudicated sample from the Denver metropolitan area. Siblings of the clinical subjects were also included. All participants in the current study met one or more of the following criteria: they had consumed at least six drinks in their lifetime, had used tobacco daily for at least one month, or had used marijuana six or more time in their lifetime.Patterns of alcohol, tobacco and marijuana use, abuse and dependence symptomatology were collected using the Composite International Diagnostic Interview-Substance Abuse Module. Abuse and dependence status as defined by the Diagnostic and Statistical Manual of Mental Disorders was determined using scoring algorithms based on whole life substance related problems. Retrospective subjective experiences were collected using a 23- item questionnaire developed by Lyons et al.. The original Lyons questionnaire was comprised of 23 items. As discussed in Zeiger et al. , due to the CADD interview length the original Lyons questionnaire was shortened after wave 1; a factor analysis was conducted on the Lyons questionnaire and 10 items with lower or mixed loadings were dropped. Subsequently, most subjects received the shortened 13-item questionnaire, thus these analyses were conducted on the 13-item response set from all subjects.

Functional annotation clustering in DAVID was used to minimize redundancy in the GO terms

As an extension of our previous work, the objective of the present study is to employ a toxicogenomics approach to compare and contrast the molecular pathways that are perturbed by MSC and TSC. However, subtle differences in gene expression provide insight into mechanisms underlying the observed differences in toxicities.A reference design with arrays as blocks of size 2 was used to analyze the median signal intensities of the two-color micro-array data. Five biological replicates per condition were used for each of the eight conditions, for a total of 80 micro-arrays. Six MSC and four TSC “outlier” micro-arrays were removed based on quality control checks , leaving a minimum of 3 replicates per group. The background signal intensity for each array was estimated using the 1533xSLv1 negative controls present on each array. All pre-processing of the data was conducted using R. The data were normalized using the LOWESS normalization method in the R library “MAANOVA”. Differential expression between the control and exposed samples for each of the three dose levels at each of the two time points was tested using the MAANOVA library. The ANOVA model was fitted to include the main effects of dose and time, with a dose by time interaction term and the array as a blocking variable. The Fs statistic , a shrinkage estimator, was used for the gene-specific variance components, and the associated p-values for all the statistical tests were estimated using the permutation method. These p-values were then adjusted for multiple comparisons using the false discovery rate approach. The least squares mean , a function of the model parameters, was used to estimate the fold change for each pairwise comparison of the six pairwise comparisons of interest among the eight treatment-by-time groups. The micro-array data for this experiment has been submitted to the Gene Expression Omnibus repository and can be accessed under record number GSE44603. Visualization and analysis of significantly changing genes was performed using Gene Spring GX 7.3. Important pathways containing significantly expressed genes were identified using Ingenuity Pathway Analysis.

Genes were assigned to functional categories using gene ontology in the Database for Annotation, Visualization and Integrated Discovery. Analyses were performed on genes that were identified as statistically significant by one-way ANOVA using four models: Hill, Power, Linear and 2◦ Polynomial. Models that described the data with the least complexity were selected. A nested chi-square test,vertical rack with cutoff of 0.05, was first used to select among the linear and 2◦ polynomial model, followed by comparison of Akaike information criterion , which measured the relative goodness of fit of a statistical model, between nested models and the power model. The model with the lowest AIC was selected as the best fit. A maximum of 250 iterations and a confidence level of 0.95 were selected. For functional classifications and analyses, the resulting BMD datasets were mapped to KEGG pathways with promiscuous probes removed. BMDs that exceeded the highest exposure dose were removed from the analysis.Three RT-PCR pathway specific arrays were used to validate the expression of specific micro-array genes. Eight nanograms of total RNA, from the same samples that were used for the micro-array study, were reverse transcribed to cDNA using an RT2 First Strand Kit. cDNA was mixed with the RT2 qPCR Master Mixes and aliquoted into 96-well plates containing primers for 84 pathway specific genes. Expression levels were evaluated using a CFX96 real-time Detection System. Relative gene expression was normalized to the Gapdh housekeeping gene, which remained unaffected under experimental conditions. Fold changes and statistical significance were calculated using the REST method for statistical significance.For the micro-array study, FE1 cells were exposed to 2.5, 5 and10 g/ml of MSC and 25, 50 and 90 g/ml of TSC. Exposed samples were compared to their matched controls, and genes were considered significantly differentially expressed if they had a fold change ≥2 with an FDR-adjusted p-value ≤0.05. A total of 1020 unique probe identifiers were significantly differentially expressed following exposure to MSC, and of these, 979 were deemed “present”.

Following exposure to TSC, 557 probes were significantly differentially expressed and 527 were deemed “present”. Of these, 356 were common to both MSC and TSC exposures. The number of significantly up- and down-regulated genes at each time point and concentration is shown in Table 1. Overall, there was an increase in the number of differentially expressed genes with increasing concentration of condensate, and there were more genes changing after the four hour recovery. At the highest concentration for both time points, cells exposed to MSC had a greater number of changing genes as compared to cells exposed to TSC. Gene expression was most altered for cells exposed to the highest concentration of MSC at the 6 + 4 h time point. Whether separated by dose or considered all together , Venn diagrams show considerable overlap in the genes that are significantly expressed at each time point following MSC or TSC exposure. Hierarchal clustering using all genes that were statistically significant revealed that the controls and the marijuana high concentration clustered independently from the rest of the samples. The remaining samples clustered first by concentration ,then by condensate type , with the last branching resulting from time. When cells exposed to TSC and MSC were analyzed separately, samples clustered first by concentration and then by time point, suggesting that concentration has the largest overall effect on gene expression. For MSC, the high concentration samples were on the first main branch, followed by control, low and medium concentrations. The results indicate that the expression profiles of the high concentration MSC exposed cells are quite distinct. For TSC, the controls branched separately from all the treatment groups. The top 10 genes with the largest overall fold changes are listed in Table 2. All of the top 10 genes were significantly up-regulated with the exception of low density lipoprotein receptor , which was down-regulated in MSC exposed cells. Of the top 10 changing genes, five genes were common to both MSC and TSC. The GO terms associated with these commongenes included multicellular organismal development, vasculogenesis, regulation of transcription, and regulation of inflammatory response. Ingenuity Pathway Analysis was used to define the pathways that were significantly altered following exposure to MSC or TSC. Fig. 3 shows the overlap in all the significant pathways between the two condensate types.

The top five most significantly altered pathways for cells treated with MSC or TSC are listed in Table 3. NRF2-Mediated Oxidative Stress Response was the most significant pathway for cells exposed to TSC at all concentrations and time points, with the exception of lowest concentration at time 6 + 4 h where LXR/RXR Activation was the most significant. For cells exposed to MSC, the most significantly altered pathways were Biosynthesis of Steroids, as well as NRF2-Mediated Oxidative Stress Response, Aminoacyl-tRNA Biosynthesis and HMGB1 Signaling. Some ofthe top five pathways were common to both the MSC and TSC including those related to oxidative stress and xenobiotic metabolism. However, inflammation pathways were more predominant for the MSC, whereas cell cycling and cancer signaling pathways were more predominant for the TSC. To further elucidate differences between the two smoke condensates, the genes that were uniquely expressed following TSC exposure or uniquely expressed following MSC exposure at the highest concentrations for the two separate time points were compared in IPA. The findings confirm the importance of inflammation and steroid biosynthesis pathways in MSC exposed cells and highlight the significance of apoptotic pathways particularly at the 6 h time point. For cells exposed to TSC,Mphase cell cycle pathways appear to be of particular importance. Gene Ontology in the Database for Visualization, Annotation and Integrated Discovery was used to apply functional annotation to all the significantly differentially expressed genes for each condensate. The full results are shown in Supplementary Tables 1 and 2. For cells exposed to MSC, significant perturbations were associated with steroid/cholesterol/lipid biosynthesis, NOD like receptor signaling , tRNA aminoacylation, transcription regulation, unfolded protein response and DNA binding. Like MSC, cells exposed to TSC had significant perturbations in transcription regulation, unfolded protein response and DNA binding. In addition, perturbations in cell cycle, p53 signaling, oxidative stress, and cancer signaling were also noted in TSC exposed cells. Fig. 5 shows the overlap of all the significantly affected ontologies between the two condensate types.This analysis revealed 19 clusters with enrichment scores greater than 2 for MSC and 19 clusters for TSC. The top clusters for MSC relevant to toxicological processes include lipid/steroid biosynthesis , RNA processing ,indoor hydroponic system cellular response to unfolded protein , tRNA aminoacylation , and positive regulation of transcription.

The top clusters for TSC relevant to toxicological processes include cellular response to unfolded protein , cell cycle , positive regulation of transcription , response to steroid hormone stimulus , and positive/negative regulation of apoptosis and cell death. To investigate early versus downstream effects, functional annotation was applied to significantly differentially expressed genes at the two separate time points. The results are shown in Supplementary Tables 5–8. For cells exposed to MSC at the 6 h time point, the analyses revealed 79 significant terms including those related to transcription activity, DNA binding, and steroid/cholesterol biosynthesis. Four KEGG pathways and 1 Biocarta pathway were also deemed significant at this time point. At the 6 + 4 h time point, 76 significant terms were identified. These terms included unfolded protein response, and tRNA aminoacylation, as well as steroid/cholesterol biosynthesis which was found at the 6 h time point. Three KEGG pathways were significant at this time point including Steroid Biosynthesis, Terpenoid Backbone Biosynthesis, and Aminoacyl-tRNA Biosynthesis. Analyses of cells exposed to TSC at the 6 hr time point revealed 67 significant terms including those associated with oxidative stress, cell death, protein unfolding, transcription regulation, DNA binding and cell cycle. In addition, 2 KEGG pathways were significant. At the 6 + 4 h time point, 32 GO terms were identified as significant with oxidative stress being the only relevant toxicological endpoint. In addition, only one KEGG pathway was significant. Overall for MSC, the DAVID analyses confirmed many of the significant pathways identified by IPA including steroid biosynthesis, tRNA aminoacylation, inflammation and apoptosis. In addition, the analyses highlighted transcription regulation, DNA binding and unfolded protein response as also significant. For TSC, the DAVID analyses confirmed the significance of IPA pathways related to oxidative stress and cell cycle. As with the MSC, the DAVID analyses also further highlighted the importance of transcription regulation, DNA binding and unfolded protein response, as well as cell death. Transcription regulation and DNA binding were significant terms common to both MSC and TSC at the 6 h time point, whereas no common terms existed for the two condensates at the 6 + 4 h time point.In our previous genotoxicity study we showed that MSC and TSC were both cytotoxic and genotoxic. However, quantitatively, MSC was more cytotoxic and mutagenic than TSC, and TSC appeared to induce chromosomal damage in a concentration-dependent manner whereas MSC did not. Our earlier chemical analyses of MSC and TSC noted that aside from the nicotine in tobacco and the cannabinoids in marijuana, the two smoke condensates contained mixtures of chemicals that were qualitatively similar though quantitatively different. The similarities in the chemical profiles and some of the toxicity findings suggested that the two smoke condensates might elicit somewhat comparable gene expression profiles. Hierarchal clustering of all the MSC and TSC exposed samples in the present study supported this notion and samples clustered first by concentration as opposed to smoke type. In addition, analysis of the top ten greatest gene expression changes relative to control revealed that half of the genes were common to both marijuana and tobacco. A number of previous studies have examined gene expression changes in pulmonary cells following exposure to tobacco smoke. Generally, these studies have shown thattobacco smoke stimulates xenobiotic metabolism, and that metabolized smoke constituents contribute to DNA damage. Following early insult, DNA damage leads to disruptions in the cell cycle such as arrest at the G2 checkpoint to allow time for response. Cellular response can include DNA repair, mutation induction through faulty repair or lack of repair, and programmed cell death of heavily damaged cells.

Hemp oil contains high contents of unsaturated fatty acids

They promote extraction by breaking down the cell walls of the structures containing the oils and hence can also lead to the extraction of essential nutraceutical and antioxidant compounds with lesser degenerative effects on the cells.Ultrasound assisted extraction of hemp seed oils was performed by Lin and his group as well as and Esmaeilzadeh Kenari and associates on hemp seeds and increased extraction yields were reported as compared to traditional extraction methods.A slightly modified ultrasound extraction method was also proposed in which solvent extraction using a Soxhlet apparatus was supplemented using ultrasound applied using an ultrasound probe.This coupled effect of conventional Soxhlet extraction along with ultrasound extraction led to an increased oil yield.Rezvankhah and his team studied the effects of Microwave assisted extraction on hemp seed oils and reported that the method was more time efficient as compared to traditional Soxhlet extraction.The oils produced were also of higher quality.Similarly,it was also reported that Microwave assisted extraction of oils from pongamia pinnata seeds was quicker and had no adverse effect on the quality of oils as compared to other conventional methods.Previously,hemp did not receive significant attention because of legal issues concerned with hemp cultivation.According to the 2018 reports by Health Canada,77,800 acres of industrial hemp were planted in Canada out of which 33,000 acres were planted in Alberta,27,100 acres in Saskatchewan,and 11,500 acres in Manitoba.It is estimated that roughly 90% of the total seed for hemp cultivation is produced in Canada which contains mostly Canadian developed varieties.Thus,it is evident that with increasing awareness there is a significant increase in hemp cultivation as well as the number of hemp processing plants leading to more research focusing on hemp seeds,grow rack especially oils extracted from hemp hearts.

Although there are previous research reports concerning the extraction of hemp oils,the literature is scanty and the scientific community lacks a thorough comparison between the effect of different extraction techniques on the quality of oils produced from hemp seeds.Previous research has mostly focused on the extraction and analysis of hemp seed oil using a single technique or a comparison between two techniques.However,a comprehensive comparative analysis of different extraction techniques for hemp heart oils operating at different temperature ranges have not been performed previously.Thus,the major objectives of the study were to Compare the extraction efficiencies of three different extraction techniques-microwave,ultrasound and cold pressing for the extraction of hemp seed oils by varying particle size and extraction conditions to obtain maximum yield.Analyze the physicochemical properties,fatty acid composition,free radical scavenging activity,and inherent chemical composition of the extracted oils to determine the quality and,understand the nature of the oils in order to suggest probable areas of application.These results indicated that the ultrasound is more effective in the first 30 min and with an increase in time,a decreasing trend in the yield was noticed.This may be attributed to the fact that due to increased time periods; ultrasound waves can disrupt more hemp heart cell walls leading to increased penetration of the solvent inside the cells resulting in more extraction.Again,the slight decrease in the extraction yield can be hypothesized to have been caused by prolonged exposure time as a result of which ultrasound oxidation of the edible oils take place either by thermal degradation or sonolysis,which can be attributed to the phenomenon of “cavitation”.Cavitations are micro-mechanical shocks affecting the structural and functional components of the cells and such an increased phenomenon in the cells lead to lipid oxidation and deterioration.This phenomenon may have resulted in a slight decrease in the oil yield upon increasing the ultrasound time.Further,an increase in the rate of cavitation leads to excessive breakdown of the cell membranes and cell walls,thus exposing the hydrophobic fatty acid tail of the phospholipids.

This might cause binding of the oil to the phospholipid and lower its extractability by the solvent.Therefore,excessive ultrasound can have a delirious effect on extraction.Again,the ultrasound time was optimized at 30 min and 60 min respectively to understand the effect of UAE power on the yield.Ultrasound powers of 20 W,130 W,and 200 W were used for UAE time of 60 min which is represented in Figure S3.On the other hand,130 W and 200 W were used for 30 min.The yields obtained by varying the ultrasound power at 60 min was not found to be significantly different.With an increase in power,the yield gradually increased and the maximum yields of 46.8 ± 3.25% and 44.9 ± 3.11% were produced at 200 W for 30 min and 60 min respectively.It can be hypothesized that when the ultrasound power is low,the energy produced by the ultrasound probe is not enough to cause the propagation of ultrasound pressure waves to cause cavitation.The results obtained are on par with previous research led by Lin et al.,who also reported that the maximum extraction yield is achieved for 200 W.The slight decrease in the yield% for 130 W and 60 min run time may be attributed to sonolysis and the cavitation phenomena.The maximum extraction yield was obtained for ultrasound power of 200 W and 30 min which was considered for further experiments.Means in the same column followed by different superscripts are significantly different.the yields except for the minimum and maximum values obtained.A comparative analysis of the extraction yields is presented in Figure S6.Results reported that there existed a significant difference between the yield obtained by CP and MW,but not between CP and UAE or UAE and MW.MW extraction produced the maximum oil yield of 54 ± 3.8% followed by 47 ± 1.97% for UAE,and 41 ± 2.82% for CP.This can be attributed to microwaves causing increased rupture of the cell walls resulting in lipolysis and proteolysis of the cell wall materials,and thus enhancing the penetration of the solvent inside the cells to extract the oil.Moreover,a temperature of 70 °C and MW exposure time of 15 min led to a movement in the media due to a reduction in solvent viscosity which enhanced the extraction yield.The mechanical effect of ultrasound promotes the release of soluble compounds from the plant material disrupting the cell walls,enhancing mass transfer,and facilitating the solvent to access the cellular contents.On the other hand,microwaves lead to an increased solvent penetration into the matrix due to the movement of dissolved ions and as a result,causes increased extraction of intracellular materials.It can further be hypothesized that ultrasound waves may have caused the lipoprotein cell membrane to break and retain some of the oils,thus reducing its extractability which led to a lower yield as compared to MW extraction.Cold pressing is a mechanical extraction technique and hence the yield is fairly less compared to the other two techniques.Overall,it can be concluded that the yield obtained by each extraction technique was more compared to the yields produced by hemp cultivars in Turkey and Pakistan.

The presence of antioxidants like tocopherols in higher concentrations in CP oils can be a reason for a higher induction time since we know that these antioxidants act as free radical scavengers and singlet oxygen quenchers.It is also known that factors like the processing and storage treatment as well as the fatty acid composition of the oil play a key role in determining the oxidative stability.Since cold pressing took place at room temperature ,it was highly likely that the oxidation reaction did not initiate during its storage leading to a higher induction time during the analysis.Electro paramagnetic resonance spectroscopy has found a wide variety of applications in detecting free radicals owing to its high sensitivity to the unpaired electrons.The close interaction of DPPH with the free radical scavengers present in the hemp seed oils presented a reduced signal intensity relative to the DPPH stock solution EPR spectrum.DPPH scavenging activity of the hemp seed oils is reported in Table 4; the addition of 0.2 g of hemp seed oils to 1 ml of DPPH stock solution quenched more than 93% of free radicals that are present in DPPH for all the oil samples in the first two hours.The declining trend in the spectral intensity for the oil sample is observed from Fig.5 and relative to the DPPH spectra.Among the three extraction techniques,UAE and MW oils have lower antioxidant activity relative to CP oil.During the extraction,cold-pressed seeds and oil were not exposed to the higher temperature like MW and UAE techniques.Due to the high-temperature processing,thermally sensitive antioxidant compounds were destroyed in MW and UAE hemp seed oils.On the other hand,CP hemp seed oil was extracted at room temperature,thereby,greenhouse grow tables the antioxidant activity of the CP is higher than MW and UAE.Further,the antioxidant activity of the oils was evaluated at 20 h,therefore the DPPH stock solution allows the dissolution of both DPPH and lipid-associated antioxidants that are present in the hemp seed oils.Upon analyzing the spectra at 20 h,enhanced scavenging activity was observed by the antioxidant compounds present in the hemp seed oils.After 20 h,1 – 3% increment in the antioxidant activity was noticed relative to at 2 h,i.e.,within 20 h of reaction with DPPH,hemp seed oils quenched or neutralized the synthetic-free radicals present in the DPPH,primary and secondary oxidation products from the hemp seed oils.As discussed in the previous section,GC–MS analysis of the hemp seed oils revealed the presence of -tocopherols,sitosterols,stigmasterol that may be hypothesized to be primarily responsible for the antioxidant properties shown by the oils.The free radical scavenging activity of the hemp seed oils showed that they are capable of quenching the reactive oxygen species and their derivatives in short time owing to the fast reactivity of the antioxidant compounds in hemp seed oils.Therefore,it was anticipated that the presence of antioxidants in the hemp seed oils,could be a value-added feedstock for the production of pharmaceuticals and nutraceuticals as reported by Polovka in his research.

Hemp has a long cultivating history all over the world,with the earliest report in Chinese ancient literatures dating back to 4000 BC.Traditionally,hemp has been widely used in textile,building materials,and paper,as well as herb medicines.In general,there are two types of hemp plants: the fifi ber type and the cannabinoids type.The fiber type hemp plants are tall and are harvested for fibers and seeds.However,they are very low in cannabinoids contents.On the other hand,the cannabinoids type hemp plant is shorter in heights and is rich in cannabinoids contents.Depending on the level of tetrahydrocannabinol in the plant,the hemp can be further classified into industrial hemp and marijuana.In recent years,the bioactive compounds,including oils,protein,cannabinoids and terpenes,etc.,in hemp plants have drawn increasing interests in both scientific research and product development.As the results,the cultivation area and production of hemp have been increasing.In 2019,the bearing acreage of hemp in the US,China,Europe and Canada were 465 787,164 819,138 863,and 92 504 acres,respectively.The global hemp industry is projected to reach $10.6 billion by 2025.Hemp seed protein contains the full essential amino acids profile required by humans,and the hemp protein isolate shows higher nutritional values than the soy protein isolates.Particularly,the contents of omega-6 to omega-3 fatty acids in hemp oil have a ratio of 3:1,which is recommended for healthy human diet.Cannabinoids such as cannabidiol ,THC,cannabigerol and cannabinol ,etc.,are gaining increasing interests in biomedical and pharmaceutical applications.Among them,CBD is the most popular topic in scientific research and hemp industry,which shows functionality in facilitating pain relief,reducing anxiety/distress,and promoting relaxation without any psycho-activities.CBD has already been applied in cosmetics industry and food products.In addition,terpenes,another group of bio-active compounds that define the characteristic aroma of the plant,are also drawing more attention together with CBD.Hemp terpenes show excellent anti-inflammatory,anti-cancer values and antioxidant activities,etc.,and have been proven to have an ‘entourage effect’ with CBD,improving CBD functionality.With these excellent pharmaceutical and nutritional values,hemp CBD and terpenes are expected to be used as future functional food ingredients,catching the wind of booming functional foods market.Currently,applications of CBD in foods are limited by several important factors: 1) Global legal regulations are still strict,which in general,prohibit the addition of CBD in any foods,beverages or supplements.However,these ever-changing regulations are opaque and varies from country to country; 2) The consumer base of hemp CBD is relatively weak.The word ‘CBD’ is unfamiliar to food consumers,and for most cultures in the world,habitual thinking associates the word ‘hemp cannabinoids’ to ‘drug’,insinuating that it is illegal and bad for human health.This further illustrates the need for the functionality and health benefits of CBD to be studied and verified; 3) Effective incorporation of the hemp CBD in conventional food products has not been extensively studied and reported,which are essential for the development of potential products; 4) Hemp plants have high yield and high moisture contents at harvest,which increases vulnerability to quality deterioration and microbial spoilage.Conventional natural drying process has low efficiency and causes product loss.

The grafting with BTCA was carried out in the laboratory using a previously published procedure

The variations in the metabolic composition of the aqueous extracts of leaves and stems were investigated by performing an OPLS-DA.A clear separation between the two classes of samples along the first two components was obtained and the analysis of the Splot allowed for the detection of the most significant x-variables and,thus,the metabolites contributing to such clustering.Specifically,the buckets having values of VIPpredictive >1 and values of p1 >|0.5| were analyzed more deeply.The spectral regions containing signals related to glucose,fructose,and galactose moieties contributed significantly to the clustering of the stems.Also,the buckets containing the signals assigned to the organic acids were characterized by significant values of VIP and p1.An analogous trend was observed for the buckets related to the signals assigned to γ-aminobutyric acid at 1.89–1.93 ppm and 3.01–3.05 ppm,and glutamine at 2.13–2.17 ppm.Interestingly,the clustering of the leaves was affected by some regions of the spectra containing very broad signals at 0.88,1.29,2.23,and 5.31 ppm ,presumably attributable to the lipids of the cell membranes and/or walls.The comparison of the 1D 1 H NOESY spectra of the leaves collected from control plants ,vigorous plants ,weak plants indicated that such broad signals were predominant in vigorous plants.Such broad signals were not observed in the aqueous extracts of stems.Also,the buckets containing the signals of ethanol at 1.17–1.25 ppm contributed relevantly to the grouping of the leaves towards the stems.These data could be explained by the fact that the leaves and,particularly the leaves sampled from vigorous green plants,have active photosynthetic processes and intact cell structures,grow racks system whereas stems of weakest plants begin to enrich with lignin and have less active photosynthesis.

The spectral regions containing these broad signals correlated positively with the calculated amounts of residual copper in the leaves.Under physiological conditions,Cu is found in two common forms,Cu preferentially binding sulfur-containing compounds having a thiol or a thioether group,and Cu ,that coordinates mainly with oxygen or imidazole nitrogen groups.The main functions of Cu are the transport of electrons in mitochondria and chloroplasts,the control of the cellular redox state ,and the remodeling of the cell wall,which is one of the major Cuaccumulation sites in hyper accumulating plants.Moreover,Cu leaf content is inversely associated with the intensity of the buckets relating to glucose and fructose and ethanol.In weakest plants,sucrose,the main soluble component of the phloem sap and translatable product of photosynthesis might be hydrolyzed into the two constituting monomers and fermented by yeast and/or bacteria producing ethanol.In a second task,the effect of the treatment with spirulina during the cultivation of hemp towards the remediation of contaminated soil was investigated.Thus,a deeper look was taken at the higher components of the OPLS model described in paragraph 3.1.Indeed,a good clustering of samples according to the treatment was visible in the t[2] vs t[5] scores plot.The second component and the fifth one explained together 11.75% of the x-variance predictive of the y-variance ,suggesting that the treatment with spirulina affected slightly the metabolic composition of the plant.Such evidence is relevant to make possible a re-utilization of the hemp,which does not change its metabolome during the phytoremediation stage.Specifically,the samples collected from plants grown in contaminated soil and the samples obtained from plants treated with a higher concentration of spirulina tended to cluster at values of t[2] >0.Conversely,the samples derived from plants treated with a lower concentration of the blue-green alga and the control ones were distributed preferentially at values of t[2] <0.A further piece of evidence was that samples C and the samples CS1 tended to separate into two clear groups along t[5].Analysis of the loading plot suggested that the uptake of all the metals,except for lead,contributed relevantly to the clustering of the plants treated with a higher dose of spirulina.Also,the average plant biomass was generally higher in contaminated plants compared to the uncontaminated ones.In addition,the plants that grew in contaminated soil and were irrigated with a higher dose of spirulina presented a higher value of biomass,confirming the activity of these cyanobacteria to promote plant growth.

The average plant contents of Ni ,Zn ,and Cd were greater in contaminated plants grown in soils added with spirulina than those grown without it.To get deeper insights into the effects deriving from the dose of spirulina,OPLS was applied to CS1 and CS0.5 samples.The observations,namely CS1 and CS0.5 ,separated along the second predictive component P2,explaining about 9.5% of the predictive x-variance.The distribution was strongly affected by the part of the plant the samples derived from,leaves or stems,with a noticeable clustering along the first predictive component P1.The corresponding loading plot showed important dose-dependent variations.Indeed,nickel,zinc,copper,and chromium were more abundant in samples treated with a higher dose of spirulina.Generally,as the concentration of spirulina increased,the residual metal content increased both in the leaves and in the stems ,whereas the Cr content increased in leaves and decreased in stems.While no dose-effect was observed for Cd,noticeable variations were exerted by increased amounts of spirulina on the quantities of Pb incorporated into the plant.Specifically,the average content of Pb in the plant was higher in CS0.5 than in CS1,suggesting that a higher amount of the blue-green alga contained in the soil might compete with hemp to sequester this metal.A piece of further evidence was that the average soil residual of all heavy metals resulted higher when it was irrigated with a higher concentration of spirulina ,suggesting that the cyanobacteria stationing in the soil may exert a strong action of metal chelation,avoiding leaching of them during the watering stage and acting as a reservoir for hemp to absorb the chelated metals.Such results find fundamentals in the reported ability of Arthrospira platensis to adsorb and accumulate all the six metals here tested through various mechanisms.Very small effects were observed on the metabolic profile when samples CS1 were compared with CS0.5.Interestingly,according to the loading plot ,the buckets at 2.66 and 2.74 ppm,containing the signals assigned to citric acid,contributed importantly to the observed grouping between the samples treated with the two different doses of spirulina.Specifically,the signals of citric acid were more intense in samples treated with a higher dose of spirulina.Considering that citric acid is one of the main chelating agents in plants,this evidence may support the hypothesis that,at a higher concentration,the cyanobacteria can chelate the heavy metals sequestering them into the soil.

As a result,less quantity of heavy metal is available for the plant to uptake,and,thus,more chelating agents inside the plant are in the free form not coordinating any metal.Industrial hemp is an annual crop grown for its seed and fibers.The three main global producers of hemp are China,Europe,and North America.Hemp is found in countless daily products: foods ,beverages ,cosmetics,and personal care products ,textiles ,papers and cardboard ,jewelry and fashion,leisure products ,animal feed,animal litter,mulching and horticulture,detergents,bio-fuel,building materials,insulation,composites ,etc.Hemp is also the object of numerous fundamental studies for innovative potential applications in bio-pesticides,biotechnology,pharmacy and medicine,paints,energy production,and wastewater treatment.Hemp shives,as valuable co-products produced during the process of extracting fiber from hemp straw,are constituted from the xylem tissue of the stem.Long considered as a by-product of the industry,used for plant mulch or animal bedding ,hemp shives are now used for house insulation,energy,and fuel production.There is also an interest in using these co-products as adsorbent materials to complex environmental pollutants since this resource is abundant,cheap,and easily burned.The last one is interesting in the context of recovery of adsorbed metals and their revalorization for example.Moreover,these materials have a highly reactive lignocellulosic macromolecular structure capable of interacting with other substances.Finally,the industry also needs to find new outlets because the volume of shives produced annually is constantly increasing.Recently,hemp fibers have been studied as adsorbent for metal removal and for the preparation of activated carbons for similar applications.However,work on hemp in shives/hurds form for environmental applications is rare.Furthermore,the identification of interactions involved in liquid-solid adsorption phenomena is often carried out using empirical mathematical models that allow the modeling of experimental results and the drawing of conclusions from the assumptions of these models.Another approach is to couple different microscopic and spectroscopic techniques to obtain information on these mechanisms.This study is part of the European research project FINEAU which brings together academics and industrialists focused on the potential use of hemp shives to recover metals from industrial effluents aiming their valorization.Two types of materials were targeted in this study by comparing shives washed with water with those chemically modified using polycarboxylic agent ,and with shives washed with water and activated with sodium carbonate.

The last one was the most efficient biosorbent of copper in our previous study among investigated raw shives and those treated with H2O,H3PO4,or KOH.The chemical treatment with Na2CO3 was carried out on a laboratory scale by copying the process already used by one of the industrialists of the project on other cellulosic materials.The objective of these two modifications is to purify and increase the capacity of raw shives towards metals,rolling flood tables while presenting high selectivity and performances independently of the pH and ionic strength representing two important issues for wastewater from the surface treatment industry.Recently,Mongioví et al reported that in the context of copper recovery by SHI-C and SHI-BTCA samples,these two materials had similar high adsorption capacities and fast adsorption kinetics,while their adsorption behaviors were very different.For example,the pH of the solution after copper adsorption onto the SHI-BTCA sample increased significantly,while that of the SHI-C sample varied much less,suggesting different interactions between these shives samples and the adsorbed copper.In addition,the amounts of sodium released into the solutions after an exchange with metal ions increased strongly in the case of the SHI-BTCA sample due to the presence of COONa groups in this material,also confirming different adsorption mechanisms.This study has two objectives: the first is to characterize the surface state of the materials before and after copper adsorption and the second is to assess the interactions between the materials and the metal ions involved in the adsorption process using microscopic and spectroscopic tools,namely computed nano-tomography ,energy-disperse X-ray spectroscopy,X-ray photoelectron spectroscopy ,Fourier-transform infrared spectroscopy,Raman spectroscopy,and X-ray absorption near-edge structure spectroscopy.Three different treatments were applied to SHI-R samples.A water washing ,an activation using sodium carbonate ,and a grafting reaction using 1,2,3,4-butanetetracarboxylic acid were carried out to study their role in the performance of samples which were further used as adsorbents for copper presents in aqueous solution.To prepare SHI-W,SHI-R samples were simply washed with water for 2 days at room temperature.After that,they were filtered and dried in an oven at 80◦C until a constant mass was obtained.

The SHI-C shives were prepared by treating SHI-W samples in 1 M Na2CO3 for 4 h at 40◦C.Thereafter,the samples were washed extensively with water until a neutral pH was obtained and dried in an oven at 80◦C until a constant mass was obtained.To obtain SHI-BTCA,SHI-W samples were pre-treated with 1 M NaOH for 3 days at ambient temperature under mechanical stirring.The shives suspension was then filtered on a filtering funnel and thoroughly washed with distilled water until the water was colorless.After drying at 60◦C in a ventilated oven for 15 h,the samples were immersed in an aqueous solution containing 100 g/L of BTCA and 30 g/L of NaPO2H2 for 15 h at ambient temperature under mechanical stirring.After draining,shives were spread on the bottom of a glass crystallizer put in a ventilated oven at 160◦C for 90 min.They were suspended in distilled water overnight under stirring,filtered,thoroughly washed with distilled water,and dried in a ventilated oven at 60◦C for 15 h.The shives were finally activated by converting the acidic form of carboxylic groups into their basic carboxylate form by immersing materials in a NaHCO3 solution under mechanical stirring for 24 h.SHI-BTCA samples were filtered,washed with distilled water until neutral pH was reached,and dried in a ventilated oven at 60◦C for 15 h.The interactions between copper and hemp-based samples were assessed by using different microscopic and spectroscopic techniques such as computed nano-tomography ,energy-disperse X-ray spectroscopy,Fourier-transform infrared spectroscopy,Raman spectroscopy,X-ray photoelectron spectroscopy ,and X-ray absorption near-edge structure spectroscopy.Nano-CT images given in Fig.3a show the typical cross-section of raw hemp shives.Namely,different tissues such as the woody part constituting the main part of the shives and some remaining pith on the right side can be observed.The woody part is made of different cell types: i) isolated or grouped in groups of two or three vessels which have a quite thin cell wall and a diameter of approximately 50-150 µm; ii) the fibers with a thick cell wall,an irregular polygonal cross-section and a diameter of only a few µm and iii) the rays which are oriented in the radial direction and are generally composed of one cell in width.

The TBA value of all treatments increased gradually up to the end of the storage time

A similar experiment was performed with THC,this time only evaluating the FBBB stability at refrigerated temperatures.The characteristic red color indicative of the presence of THC did form; however,like the hemp,the color was duller than when performing the usual procedure.Finally,FBBB was preloaded onto PSPME substrates and left in refrigerated temperatures for a week and were then used to evaluate 1000 ppm THC and 1000 ppm CBD solutions.Red and orange colors did form,respectively,but they were duller like all the other chromophores formed using FBBB as a preloaded salt.There is a growing interest in natural bioactive compounds both by producers and consumers in the food and pharmaceutical industries.Particularly,consumers are looking for foods without artificial and harmful preservatives that can promote their health.Essential oils as natural food preservatives are,generally,extracted from medicinal plants and herbs for their noticeable biological activities.EOs are complex combination of secondary metabolites,including terpenoid hydrocarbons,phenol derivatives and oxygenated terpenoids ; however,due to having volatile components,their usage is limited; the volatile compounds can be degraded easily by adverse external conditions such as light,oxygen,temperature,pressure,and pH.In addition,controlled release of EOs is needed when used for specific purposes like food additives.In recent years,the isolation and utilization of EOs from agroindustrial wastes and by-products have gained much research interest.Industrial hemp’s inflorescences are usually discharged during the conventional hemp processing,resulting in an underused biomass for future uses.They are a rich source of EOs and contain mainly monoterpenes and sesquiterpene hydrocarbons like -caryophyllene,α-pinene,myrcene and α-humulene,which exhibit important biological activities.Valorization of hemp by-products is a matter of interest for producers,allowing them to increase the market value of hemp cultivation.Some studies have recently been carried out on the functional and pharmacological applications/properties of industrial hemp essential oil due to their antioxidant,trimming trays for weed antimicrobial,and anti-inflammatory activities.

There is much interest in developing biodegradable nanoparticles as an effective delivery system for delivering lipophilic food bioactives.Proteins are attractive options for designing polymeric NPs as suitable wall materials thanks to their amphiphilic nature compatible with many active substances,as well as excellent functional properties.Whey protein,as a typical cheese processing by-product,is commonly used to foods due to its great nutritional value and techno-functional properties such as gelling,foaming and emulsifying.Protein fibrillation is used nowadays for fabrication of protein fibrils having novel functionalities and improved structure stability.Heating the protein above 80 ◦C for 5–24 h at low ionic strength and acidic conditions can result in production of WPI fibrils ,which are more suitable as delivery carriers comparing to native proteins,due to having multiple functional groups,and thus,promoting different interactions with numerous and drugs and nutrients.Protein complexation has recently been proposed as a promising and efficient way for improving the bio-availability,chemical stability and dispersion of bio-active compounds in an aqueous environment.Mung bean protein is a significant plant protein that demonstrates high potential as sustainable protein source for its availability,nutritional value,hypoallergenic,and desirable foaming,emulsifying,gelling,and film-forming capabilities.The rainbow trout as an extremely perishable food belongs to the Salmonidae family.Recently,the demand for rainbow trout has increased remarkably,and this could be due to its desirable characteristics.Due to the demand for fresh refrigerated fish with extended shelf life,notable study has been directed toward prolonging the shelf life of this fish.Although,there are scarce studies on the characterization and fabrication of IHEO encapsulated in complexation of WP nanofibrils and MBP NPs.The present study is to manufacture and characterize WPNFMBP NPs as a novel wall material for loading IHEO.Furthermore,application of IHEO-reinforced WPNF-MBP NPs as a potential natural additive for increasing the shelf-life of Rainbow trout fillets during refrigerated storage is going to be evaluated.The chemical changes of Rainbow trout fillets were monitored through the measurement of TVB-N,TBA and PV values of the fish oil during storage.Hydroperoxides are the main products of lipid oxidation; thus,measurement of peroxide values is helpful for indicating oxidative rancidity.As depicted in Fig.3a,PV in the control samples increases from 1.33 to 8 meq O2/kg at day 10 and declines after this day,maybe due to the reaction of hydroperoxide with protein as well as the collapse of primary oxidation products into secondary oxidation products.PV level tends to increase toward the end of the storage period.

A similar pattern of hydroperoxide content has also been reported in Rainbow trout fillets during storage.The samples coated with WPNF-MBP and IHEO-reinforced WPNF-MBP NPs showed significantly lower PV levels than the control during the storage period.The literature considers a PV value of 20 meq O2/kg oil is as the maximum limit for fish.Our results indicated that the IHEO-reinforced WPNF-MBP NPs coating is significantly reduced the amount of primary lipid oxidation in fish during storage; this is in agreement with the results of other similar investigations.TBA index is a common indicator for evaluating the lipid oxidation level by measuring such oxidation products as aldehydes like malondialdehyde.The recommended perceivable level of TBA in food as objectionable odour is about 1–2 mg MDA/kg ; however,Raeisi et al.proposed the maximal acceptable level 5 mg MDA eq/kg in Rainbow trout with no negative effects on its safety and quality.As indicated in Fig.3b,the TBA level remained below the maximal acceptable level during the 14-day storage.However,in the uncoated samples,the TBA value was much higher than in the coated samples ; however,the initial value of TBA was in the range of 0.09–0.13 mg MDA/kg,consistent with reports of other researchers for fresh Rainbow trout.The slightly lower oxidation rate in the IHEO-reinforced WPNFMBP NPs coatings can be because of the oxygen barrier and antioxidant activity features of IHEO and WPNF.The antioxidant mechanism of IHEO can be due to its polyphenols,which show scavenging activity against free radicals through providing hydrogen atoms to free radicals,preventing radical chain initiation,and thus,preventing the formation of metal catalyzed free radicals.On the other hand,the WP coatings provided a great protection against oxidation.IHEO addition improved the WPNF-MBP NPs coatings’ antioxidant properties.WPs exhibit antioxidant activity through different ways: 1) formation of a coating,which is a good barrier for O2 permeability coated samples during storage,2) enjoying a free radical scavenging capacity by some amino acids and metal chelation by bovine serum albumin and lactoferrin,3) having sulfhydryl groups partially responsible for their antioxidant properties,and 4) containing β-lactoglobulins and α-lactalbumin with good antioxidant activity for having amino acid residues.Furthermore,particle size reduction of IHEO and WPNF-MBP coatings after nanoencapsulation can increase these ingredients’ specific surface; thereby achieving an efficient amount of free radical absorption would be achieved.

TVB-N is produced from degradation of proteins and non-protein nitrogenous compounds,mainly as a result of microbial and enzymatic activities,as an indicator of meat and fish spoilage.The TVB-N level in the control samples was initially 6.68 mg N/100 g,and there was no significant difference among the different samples at the first day of storage.By increasing the bacterial counts,the TVB-N value increased gradually in all groups; however,in the samples coated with WPNF-MBP and IHEO-reinforced WPNF-MBP NPs,the TVBN value was significantly lower than in the controls.Considering the maximal acceptable level of 25 mg N/100 g in fish flesh ,the TVB-N limit was achieved at day 8 of storage in the controls,while in the WPNF-MBP coated samples,this limit was reached by the 10th days,and in the IHEO-reinforced WPNF-MBP NPs coated samples,it was lower than this limit during the whole period of storage.At the last day of storage,the TVB-N value for the IHEO-reinforced WPNF-MBP NPs coated samples was 12.1 and 9 mg N/100 g lower than the control and WPNF-MBP coated samples,respectively.We previously mentioned that TVB-N is produced mainly because of the bacterial degradation of the nitrogenous compounds of proteins and non-protein products,its low value in the coated samples can be due to the microbial inhibitory effects of treatments that decrease the formation of TVB-N.Similarly,Shokri et al.found that coating of Rainbow trout fillets with chitosan-Ferulago angulate EO nano-emulsion retarded the increasing rate of TVB-N index during storage at 4 ◦C.Ozogul et al.found that nano-emulsions based on plant EOs significantly inhibited the TVBN formation in Rainbow trout fillets during ice storage.To the best of our knowledge,there are no studies on the effect of IHEO-reinforced WPNFMBP NPs coating on the formation of TVB-N in Rainbow trout fillets; however,trimming tray with screen the lower TVB-N in the samples coated with IHEO-reinforced WPNF-MBP NPs in the present work could result from the antibacterial efficiency of WPNF-MBP coating facilitated by nano-encapsulation of IHEO.Fig.4 illustrates the overall acceptable scores of the control and coated Rainbow trout fillets with WPNF-MBP and IHEO-reinforced WPNF-MBP NPs.In the present study,appearance,color,odor,and texture were taken into consideration in the overall acceptance scoring.The overall acceptance scores were in the range of 1–5.High preference levels represent high element scores.All samples exhibited high sensory and quality scores at the first day of analysis.An overall acceptance below 3 of fish is considered to be unacceptable for human consumption.The overall acceptance scores of the coated and control fish samples showed a decreasing trend up to the end of storage time.The samples coated with IHEO-reinforced WPNF-MBP NPs exhibited a higher score comparing to the other samples during the refrigerated storage.The control samples’ sensory properties were ‘unacceptable’ by the 10th day.Also,at the day 12,the samples coated with WPNF-MBP did not achieve acceptable scores due to their unpleasant appearance and sticky surface; however,the incorporation of IHEO reduced these defects.Hence,the samples coated with IHEO-reinforced WPNF-MBP NPs had better sensory scores than the others for control the lipid oxidation and bacterial population.

These results are consistent with the findings of O˘ guzhan Yıldız and Yangılar and Farsanipour et al.for Rainbow trout WP-based coated samples incorporated with EOs stored at refrigerator condition.Industrial hemp,Cannabis sativa L.is a multifaceted crop that is increasingly being considered by farmers looking to diversify and reduce their ecological footprint.Industrial hemp is grown for both fiber and food,and is also used in cosmetics and for medicinal and nutraceutical/ pharmaceutical purposes.A major factor contributing to the sustainability of hemp is that most parts of the plant can be used,and innovation is contributing to additional uses of hemp for biofuels,high-performance textiles and natural insecticides.Hemp has long been used as a food source and in traditional medicine ,and this has stimulated research into its use as a functional food.In addition to its healthy oil and protein profiles,several bioactive peptides have been found in hemp seed,as well as polyphenols and other effective antioxidants.Hemp seed should be relatively easy to get to food markets as seed processing can use existing production facilities with some adjustments.Hemp seed is actually an achene or nut,with a hard outer shell ,a papery testa,and an inner seed.Industrial hemp is classified as Cannabis plants with low levels of Δ9- tetrahydrocannabinol ,depending on the country and state.It was recently estimated that the global production of hemp will double in the four years from 2016 to 2020,and some states in Australia have already more than doubled their production.This resurgence of interest in hemp has led to an increasing number of states in the USA growing low THC hemp,and as of 2017 all states in Australia have legalized cultivation of industrial hemp for food and fiber applications.In comparison to other crops hemp has been described as sustainable because it is relatively resistant to biotic and abiotic stresses thereby reducing agronomic inputs.In temperate Australia industrial hemp is grown as a summer crop and requires supplemental irrigation.Hemp has a relatively high water requirement compared to dryland cereals,although much less than cotton.A major advantage of hemp from an agronomic point of view is the rapid growth of seedlings such that it effectively outcompetes weeds.This and the fact that it has relatively few pests and diseases makes hemp better suited for organic production than many other row crops.In Australia,some pests and diseases have been observed,but in most cases there has been no significant impact on productivity.Industrial hemp is suited to a wide variety of soil types as long as they are fertile with good drainage and water holding capacity.When C.sativa is grown for fiber,tall varieties are used because of their increased biomass.Shorter varieties are being bred with higher harvest index that are specifically targeted to food markets.Characterization of FINOLA seed showed that it contains approximately 30% oil and 25% protein.Analysis of lipids of FINOLA seed revealed that over 80% are polyunsaturated including two essential fatty acids,linoleic acid and α-linolenic acid.Hemp seed contains a ratio of omega-6 to omega-3 in a desirable range between 2:1 and 3:1.Current western diets are generally deficient in omega-3 fatty acids,with a high ratio of omega-6:omega-3,due to the increased intake of vegetable oils including sunflower and corn oils,which have ratios of >50:1 omega-6:omega-3.

It confirms that there was indeed a direct effect of hemp fabric on the Izod impact energy of the composites

Considering the average lengths before and after extrusion-injection molding , a reduction of about 2 times in the case of HF, 2.5 times for HF and 4 times for HF was observed. It follows that the reduction of fiber length was greater for longer initial fibers, similar to the results on simple PP/HF composites. Moreover, their length in the final composites was greater than for shorter initial fibers, which is consistent with previous results. For a deeper evaluation of fiber length reduction in PPM/HF composites after extrusion and injection molding, the length histograms of the initial fibers, collected after the mechanical treatment and before the incorporation in composites are given in Fig. 5. The representative images of the initial hemp fibers, HF, HF and HF are also shown in this figure. A thorough analysis of the initial fiber length shows that about 60% of HF are under 1mm in length, compared to 90% after processing, and only 27% in the case of HF and 4.5% in the case of HF, compared to 72% and 47% after processing. It follows that the proportion of “fines” is drastically increased in the case of longer fibers but it is maintained lower than 50% for HF. A side-by-side analysis of optical microscope images of HF before and after incorporation in composites highlights the intense defibrillation of the fibers. This is due to the concerted action of temperature and shear forces during processing in the double-screw extruder and injection molding machine. Average diameters of 91 ± 64, 99 ± 48 and 119 ± 69 m were obtained for the initial fibers, HF, HF and HF, after mechanical treatment. The lower dm value for HF and HF was caused by the more intensive mechanical treatment provided by the automatic cutting. The dm of HF decreased to 17.1 ± 11.1, 18.8 ± 9.8 and 23.8 ± 12.4 m after incorporation in PPM 30HF, PPM 30HF and PPM 30HF composites. Therefore, a rough calculation of the aspect ratio of the fibers,grow tent kit the length to diameter ratio, shows an increase from 12, 26 and 35 for mechanically treated HF,and to 33, 39 and 43 for HF in the composites containing these fibers.

Although both the length and the diameter of HF diminished after the melt processing of composites, the defibrillation seems more intense, which leads to an increase in the aspect ratio of the fibers. The analysis of fiber size after processing will be further used to understand the thermo-mechanical behavior of these composites.Natural fibers used as reinforcement of polymer matrices have been intensively investigated in recent decades and considered for diversified applications, from automotive, civil construction, sports, furniture, and packaging industries as well as in ballistic armors. The interest in the use of natural fibers ranges from their availability and renewability to intrinsic features, such as low density, biodegradability, cost-effectiveness, and low processing energy. In addition, the current need for replacing synthetic materials due to problems related to sustainability and non-renewable sources of energy led to a surging number of works to optimize their composite properties. Among the well-known natural fibers, the hemp fiber has historically been used in several applications such as textiles, manufacture of papers, and even in the pharmaceutical industry. Archaeologically, hemp is the oldest discovered natural fiber. The Columbia History of the World stated that the most antique relics of human industry are bits of hemp fabric discovered in tombs dating back to approximately 8000 BC. Nowadays, the plant Cannabis sativa, from which the industrial hemp fibers are extracted, is again widely grown in China, Europe, and Central Asia, after years of restriction in some countries. In fact, the C. sativa species produces less than 0.2 wt% of tetrahydrocannabinol , the, which is too low for use as a recreational drug, as in the case of marijuana, a popular denomination of Cannabis indica. The C. sativa fibers, responsible for keeping the trees upright, have its structural properties studied for reinforcement composites due to their remarkable strength and stiffness. Some historical applications corroborate its potential, such as when Henry Ford tried to adopt hemp-polymers composites in the automotive industry in 1941. Another example was the constructive details of the window frames and floor coverings, made of hemp fiber reinforced polymer composites used in facilities during the 2008 Beijing Olympics. Indeed, due to a relatively larger amount of cellulose and hemicellulose and lower microfibrillar angle,which are related to mechanical properties, the hemp fiber displays a remarkable tensile strength , elastic modulus and total strain. As such, after sisal, hemp is the world’s most applied natural fiber as reinforcement in composites.

However, a recognized disadvantage is the aforementioned variability in their properties, which is inherent to natural fibers in general and requires that each lot of fiber, obtained from a given supplier, to be preliminarily tested. This procedure will be carried out in the present work regarding basic mechanical and thermal properties. According to Shahzad, the main hemp fiber reinforced composite matrices are polypropylene and unsaturated polyester due to easy processing and cost. On the other hand, with comparable properties and cost of UP, epoxy is another thermoset polymer that has not been often used as a composite matrix for hemp fibers. As shown in our literature survey in Fig. 1, there is an emerging tendency to study epoxy composites reinforced with hemp fiber. In this decade an approximately exponential rise is occurring in the related number of articles. According to Fig. 1, today seven new publications already have a DOI number. In particular, flexural strength and modulus of 30 vol% of hemp fiber epoxy composites were found to surpass the corresponding flexural strength and modulus of polyester composites with an equal amount of same hemp fibers. In spite of the raising interest, Fig. 1, for epoxy composites reinforced with hemp fiber, no work has so far specifically investigated epoxy composites with hemp fabric. A surging area, where natural fiber/fabric reinforced polymer composites are attracting increasing attention, is that of personal ballistic protection. In addition to the numerous works cited in the aforementioned review papers, several recent publications reported on the ballistic protection provided by NFCs. As part of multilayered armor system , these NFCs display ballistic performance superior to commonly applied Kevlar and Dyneema laminates. Although much weaker than synthetic aramid and ultra-high molecular weight polyethylene, natural fibers possess the same capacity of absorbing the ballistic energy by capturing the fragments after the bullet impact against the MAS front ceramic. In view of these disclosed NFCs superior ballistic performance combined with lower density, cost effectiveness and sustainability, one might expect that hemp fabric reinforced epoxy composite could be used for ballistic protection. In a pioneer works, Wambua et al. investigated the response of 46 vol% of hemp fabric reinforced PP composite to ballistic impact by 1.1 g fragment simulating projectile . Their main result revealed an absorbed kinetic energy of 36 J associated with a limit ballistic impact velocity of 260 m/s.

Therefore, the primary objective of the present work was to investigate for the first time the ballistic performance of epoxy composites reinforced with up to 30 vol% of hemp fabric against 0.22 ammunition. As a preliminary investigation, the mechanical and thermal properties of the aforementioned composites are also investigated to characterize the specific reinforcement effect of our Brazilian supplied hemp fabric. The possible variability of results was statistically evaluated using the analysis of variance and the Tukey test.Table 1 shows the results for all conditions: composites reinforced with 10, 20, and 30 vol% of hemp fabric and neat epoxy, which was used as a control group. For better visualization, the average values were plotted in Fig. 4. All tested specimens were completely fractured, validating the results obtained as required by the standard. The graph in Fig. 4 presents a continuous increase in the impact energy along with the fabric volume fraction and a lower standard deviation for the plain epoxy resin compared to the composites due to the non-uniform proprieties of natural fiber. This behavior was observed in previous works for different composites and is expected as the amount of reinforcement is related to the increase of energy necessary to break the samples. Comparatively, the 30 vol% hemp fabric-epoxy composite presented only about 36% lower absorbed energy than the 30 vol% curaua-polyester composite, which, in another work, was presented as an acceptable ballistic performance. Fig. 5 shows the broken specimens after the Izod impact test. By visual analysis, the fracture surface of specimens with 0 and 10 vol%, and , respectively, reveal a smoother surface related to a brittle fracture tendency. On the other hand, the fracture surface of the samples reinforced with 20 and 30 vol% hemp fabric,indoor grow tent and gets more irregular as the volume fraction of reinforcement increases, which could indicate a brittleeductile transition. From the results, in Table 1 and Fig. 4, Table 2 presents the ANOVA analysis for the impact energy absorbed. The equality hypothesis with a confidence level of 95% was rejected, as F was higher than the Fc.The Tukey test honest significant difference for the absorbed impact of the plain epoxy result and the composite values above this result present a significant difference. Hence, the results in Table 3 show that the impact strength of the 30 vol% hemp fabric composites is the best amid the tested composites. It is important to note that the values are always greater than the HDS calculated, which suggests that the incorporation of hemp fabric provides an effective reinforcement to the epoxy resins for all volume fractions.

This points toward what was already presented in early works, in which the reinforcement contributed to a greater rupture surface area by interrupting or deviating the crack’s propagation.Table 4 presents the average results for the tensile strength of the hemp fabric-reinforced composites. From these values and the strain of the samples, it was also possible to calculate the elastic modulus. These results are plotted in Fig. 6 and , which correspond to tensile strength and elastic modulus, respectively, for better visualization. Table 4 also shows literature values for the tensile strength of the same neat epoxy resin. The results in Table 4 and Fig. 6 display relatively poor tensile properties for the 10 and 20 vol% hemp fabric reinforced composites comparatively with the neat epoxy resin. It suggests that these two fractions of fabric do not act as reinforcement when tensile loads are applied to the material. Consequently, the epoxy matrix bears most of the load applied during the test. As such, the hemp fabric incorporation has a negative effect on the composites and acts more as flaws in the material’s structure. However, the composites with 30 vol% hemp fabric improved considerably the tensile strength compared to the neat epoxy resin, which means that this amount of hemp fabric acts as an effective reinforcement for the material due to the mechanisms of restrict rupture of the fibers in the fabric that impart the tensile strength. This good performance, compared to other composites reinforced with hemp fibers, is an important parameter for the ballistic performance of the composites, as the tensile strength is associated with the penetration resistance of the target material. Also, it is possible to observe a considerable improvement of the elastic modulus for the composites reinforced with 30 vol% hemp fabric, which could be related to the higher stiffness of the hemp fiber. Although, the 10 and 20 vol% hemp fabric show lower values with a slight decrease attributed to a nonuniformity of the reinforcement’s properties. To better understand the behavior of the analyzed composites under tensile stress, Fig. 7 presents SEM images of the broken specimens, in which it can be noted different fracture mechanisms. The “river marks” present on the composites reinforced with 10 and 20 vol% hemp fabric, shown in Fig. 7 and , reveal low effectiveness of reinforcement of these composites due to limited fabric content and causes a brittle fracture for the material as the epoxy matrix bears most of the load.