Cannabis Grow

Marked increases in cannabis sales were reported by industry and business sources during the COVID-19 pandemic,1 and studies of cannabis users in the U.S.,2 the Netherlands,and Canada reported increased cannabis use during the pandemic. Content analyses of Twitter and other social media and online sources during the pandemic found increased discussion of cannabis as treatment for COVID-19. The number of cannabis dispensaries is increasing with legalization and dispensaries are an important source of marketing messages,but it is unknown to what extent online cannabis dispensary marketing activities may have contributed to increased pandemic sales. We analyzed cannabis dispensary websites to gain insight into cannabis marketing practices at the start of the COVID-19 pandemic, leveraging an existing study of a small geographic area with two different historical policy contexts. The region from the San Francisco/Bay Area extending east to the Reno area of Nevada is readily accessible by car, but includes two states with contrasting regulatory contexts: California has a long history of acceptance of cannabis including the counterculture of the 1960-1970s, medical marijuana legalization in 1996, and a longstanding cannabis cultivation.In contrast, Nevada’s medical marijuana policy was implemented fairly recently in 2015. Both states approved adult use cannabis in 2016, and deemed cannabis dispensaries essential during the pandemic. Dispensaries remained open in California; in Nevada, dispensaries were initially limited to delivery, but in May 2020 allowed curbside pick-up and in-store purchases.An August 2020 cannabis industry report found that sales rose overall during the COVID-19 pandemic, and stated that “e-commerce solutions were the key to success”.As part of an ongoing surveillance study comparing dispensary websites in San Francisco, Alameda and Washoe Counties, we noted special COVID-19 announcements appeared days to weeks following lockdown and analyzed these to gain insight into industry marketing responses to the pandemic.

We conducted a content analysis of website announcements, comparing dispensaries in San Francisco/Alameda Counties and those within a 30 mile radius of Reno, Nevada, between April-May 2020. We obtained lists of all licensed dispensaries from local health departments and verified the businesses were open using online resources . We included all dispensaries with functional websites . Three trained researchers reviewed all websites and recorded all content related to COVID-19 with screenshots. COVID-19 announcements appeared on websites shortly after the stay-at-home orders were announced, often as pop-up windows appearing on top of the home page, or as an extra web page. We coded only content from the dispensary, not unrelated pop-up ads. The content code book was adapted from a prior website content analysis instrument,and the team iteratively reviewed, discussed,best trimming trays and revised codes, including six new codes specific to the COVID-19 pandemic . Two authors double coded all COVID-19 announcements for the presence of each theme; the unit of analysis was the website. The team met weekly to review and discuss discrepancies in coding and to resolve conflicts, using a fourth investigator to adjudicate if needed. Inter rater reliability measured by Krippendorff’s alpha was 0.77 – 1.0 for COVID-19 variables. COVID-19 announcements were present on 25/32 of dispensary websites in San Francisco/Alameda counties and on 9/15 of websites in the Reno area. Of the websites with COVID-19 content, almost all announced operational changes.72% of San Francisco/Alameda and 56% of Reno websites announced safety measures like wearing masks, hand washing, cleaning surfaces, temperature checks, physical distancing, notouch payment or eliminating smell samples. Some asked patrons not to come to the dispensary if feeling ill, with reference to sick or immuno compromised clients. The majority of websites made references to, or provided links to, government or public health resources, either as the explanation for changes in operations, or to demonstrate that the dispensary was cooperating with health authorities. The look and feel of COVID-19 website announcements varied widely; most dispensaries utilized simple “pop up” windows on the site home page with text announcements to customers of altered hours, access or pick up policies. However a few created custom graphics for promotions or discounts, and one dispensary adorned their logo with a mask. Health-related announcements were present in several forms. Of San Francisco/Alameda County dispensary websites, 36% referred to their status as an essential service, a theme not found on Reno area websites. The status as an essential service was often accompanied by references to cannabis as a medicine, or a connection to health authorities. For example, one San Francisco dispensary posted a quote “Cannabis is an essential medicine for many San Francisco residents.

Dispensaries can continue to operate as essential businesses during this time, while practicing social distancing and other public health recommendations” that was attributed to the San Francisco Department of Health. Another announcement stated, “So, what are the essentials? Groceries, prescription drugs, gas, urgent medical care, and weed. This list is what’s necessary for the health and safety of us all during this time.” More frequently, COVID-19 announcements included more general health statements such as, “The health and safety of our staff and customers is of the utmost importance to us.” A few dispensaries gave advice about ways to use cannabis, implicitly to avoid COVID-19 infection, such as, “Opt for non-invasive forms of ingestion – edibles, tinctures, drinks, soft gels” and “Do not share cannabis joints, vapes or edibles.” One dispensary suggested cannabis use for anxiety, “If you are experiencing anxiety, consider using products with CBD, THCA, CBN, or low doses of THC” and this dispensary also suggested bulk purchases as a way to mitigate COVID-19 infection risk, “Limit your need to travel by stocking up on your supply. We are offering a 10% discount when you buy 4 eighths or 4 extracts , stackable with our senior and veteran discounts.” 44% of Reno websites included general statements about the importance of their patrons’ health, while general statements were found on only 16% of Bay Area websites. However, all announcements that recommended specific ways to use cannabis to mitigate COVID-19 risk or anxiety were from Bay Area dispensaries. One Bay Area dispensary asked patrons to contact local county supervisors to advocate for cannabis as an essential service and provided links. A minority of sites in San Francisco/Alameda Counties offered COVID-19 discounts or specials, including a “heroes discount” for health workers, and discounts for those laid-off from work. One San Francisco dispensary sold surgical masks and hand sanitizer. This is, to the best of our knowledge, the first study describing the novel COVID-19- related marketing communications from cannabis dispensaries during stay-at-home orders. We found that like other businesses, most cannabis dispensaries implemented operational changes, including delivery, pickup, and sanitation measures and made general statements that health and safety was important to them. In addition, however, we found some announcements on dispensary websites that were more unique to cannabis sales, such as those that linked cannabis and health, either by referring to cannabis as medicine, making references to government or health authorities, and utilizing rhetoric similar to healthcare providers, including making recommendations for cannabis forms to reduce disease transmission risk or strains to use if one was experiencing anxiety. The study’s strength is that it provides a novel and timely snapshot of practices that may influence cannabis consumption in a rapidly evolving context. Surveillance of cannabis websites can complement and help to explain findings of the behavioral studies reporting increased cannabis use. This aspect of cannabis marketing may be more agile and difficult to capture with traditional marketing surveillance; the COVID-19 announcements appeared soon after lock downs. By October 2021, all of these announcements had disappeared from all but one of the dispensary websites . This study captured a unique transient marketing activity, suggesting that during future societal events or stressors that might impact cannabis consumption, rapid surveillance of cannabis dispensary websites is warranted.

The study has several limitations: it has a small sample size, this cross-sectional analysis of dispensary websites does not represent other types of cannabis websites or places without legal cannabis,trimming tray and it addresses only dispensary COVID-19 announcements, not consumer behavior. This study adds perspectives on new COVID-19 related content to prior analyses of cannabis advertising,which also found retailers positioning themselves as healthcare providers. While we did not find explicit claims that cannabis could treat COVID-19, some announcements suggested ways to use cannabis to avoid infection, or suggested cannabis products to use if experiencing anxiety; these implicit connections between cannabis and health are consistent with prior studies finding cannabis dispensary health benefit claims.This analysis was limited only to the COVID-19 announcements; a subsequent analysis of the full website content found that anxiety was the most common mental health claim, present on 80% of websites in this sample.This limited analysis of the COVID-19 announcements from a single time point early in the pandemic likely underestimates the potential influence dispensary marketing could have on cannabis consumption. While COVID-19 announcements had largely disappeared from dispensary websites by October 2021, an informal review of the dispensary websites included in this analysis in October 2021 found that one featured a blog post on the topic, “Can marijuana cure coronavirus?” and several websites featured blog posts about using cannabis for anxiety, a topic indirectly relevant to the stress of the ongoing pandemic. While this study does not address consumer behavior, another study found in states where cannabis is legally sold, people with mood or anxiety disorders were more likely to use cannabis to selfmedicate.The marketing tactics we observed to maintain cannabis availability and align with health authorities might contribute to increased cannabis use, particularly since other studies show stress and decreased access to medical services were associated with the pandemic. This study demonstrates that cannabis dispensary websites are a timely source of data on industry responses to rapidly changing events and public health policies that may impact cannabis consumption.

The study identified two tactics in the COVID-19 announcements preserved which might contribute to increased cannabis consumption: preserving ready access to cannabis as an essential service, and reinforcing perceptions of cannabis as a medicine and dispensaries as health services. While use of online ordering and delivery services has been documented in prior analyses of cannabis websites we found these services became nearly universal after stay-at-home orders. The increase in home delivery of cannabis and other intoxicants that accompanied the COVID-19 pandemic may persist, posing new challenges for surveillance research.Future studies should address the impact of cannabis marketing and messaging on consumer cannabis consumption and health-care seeking behavior during stressful events. In 1996, California became the first state to legalize the use of medical cannabis. Children’s exposures to cannabis increased by a factor of three from 2010 to 2016. For children under 6 these exposures were primarily accidental; for adolescents these exposures were more commonly related to cannabis misuse. In November 2016, two decades after the medical legalization, Californians passed a ballot measure legalizing recreational cannabis. Recreational cannabis legalization has been associated with increased exposures, and these disproportionately affect vulnerable groups, particularly children, young adults, and older adults. As of 2021, eighteen states and the District of Columbia had legalized recreational cannabis and cannabis had been decriminalized in 27 states. In the first two years after recreational legalization in Oregon and Alaska, local poison control centers reported increased accidental cannabis exposures among children, commonly leading to sedation. Children were also more likely to be admitted to intensive care after exposure. After Colorado legalized recreational cannabis in 2012, unintended health consequences included increased healthcare visits due to ingestion, cyclic vomiting syndrome due to frequent use of high THC concentration products, and burns from THC extraction-related explosions. Colorado also reported increased healthcare visits due to accidental ingestion of edible products by children and increased unintentional overdoses, while among adults, concentrated products such as resins and liquid concentrates resulted in increased toxic exposures. In 2013, there had been a 16 percent increase in hospitalizations in Colorado due to cannabis in pediatric patients and a 30 percent annual increase in call rates to poison control. COVID-19 shelter-in-place orders may also have affected cannabis exposures; with increased cannabis use anticipated in response to lock downs. Mental health stress associated with the COVID-19 pandemic has been associated with increased desire to use recreational substances, especially in states where cannabis is legal.

Accordingly, the ethanol and SF extracts hemp seed appears to both scavenge the free radicals and also restore the expression of antioxidant enzymes. Hence, the expression of antioxidant enzymes activity by hemp seed is might be ascribed to the presence of bio-active metabolites. This study is the first report on the expression of antioxidant enzymes by hemp seeds in HepG2 cells.It also up-regulate the expressions of SOD, GPx and CAT enzymes in concentration dependent manner. These findings strongly suggest that ethanol and SF extracts of hemp seed may participate in cellular protection as an antioxidant molecule and stimulate the expression of antioxidant enzymes. It could be concluded that hemp seeds appear to be a useful of source of a therapeutic agent for the treatment of oxidative stress mediated disorders. Recreational marijuana has been legalized for adults 21 years of age or older in several states beginning with Colorado and Washington in 2012. In 2014, Alaska, Oregon, and the District of Columbia voted to legalize recreational marijuana, followed by California, Massachusetts, Nevada, and Maine in 2016. We use data for students at Washington State University to explore the role legalization plays in marijuana use among college students, a population generally thought to be predisposed towards risky behavior, including marijuana use. Our main hypothesis is that legalization of recreational marijuana induces more students to use marijuana by lowering one or more of the costs of using it. These costs may include the threat of punishment, the price and/or availability of marijuana, a lack of social acceptability, and an inherent desire to be law-abiding. Throughout the U.S., marijuana access has been relaxed in three general ways: decriminalization, medical marijuana legalization , and recreational marijuana legalization . In the early 1970s, eleven states officially decriminalized the possession of small amounts of marijuana.Though there is some evidence that use may increase with decriminalization ,hydroponic grow tent most research finds no evidence for such an increase .

Since 1996, 28 states have legalized medical marijuana, which still prohibits recreational use. Most evidence shows that MML has not increased marijuana use among people younger than 21 , although Pacula, Powell, Heaton, and Sevigny find that MML increased use and abuse by those under and over the age of 21. Other studies find MML is associated with more non-medical use and abuse , more marijuana-related arrests and marijuana rehabilitation treatments , and a decrease in the price of illegal marijuana . There have been no direct assessments of the impact of RML on marijuana use of college students, though Cerdá et al. find some evidence that RML is associated with lower perceived risk and higher use for youth. Pacula predicts that use will increase. Hall and Lynskey predict that the price of marijuana will drop and heavy use will increase. Anderson, Hansen and Rees find evidence that RML has decreased the price of marijuana. Our population of interest in this paper is students at WSU in Pullman, Washington. Many changes with respect to marijuana law and availability have occurred in Washington in the past two decades. In 1998, Washington decriminalized marijuana for adult medical use, with qualifying conditions expanding in 2007, 2010, and 2011. In November 2012, Washington passed Initiative 502, which legalized the possession of marijuana for personal recreational use by people aged 21 and older and established a structure for licensing and taxing the production and distribution of recreational marijuana. Legal possession and use of marijuana took effect in December 2012. The first licensed retail stores opened in July 2014. In this paper, we investigate whether the 2012 legalization of recreational marijuana is associated with an increase in use above the long-term trend toward more use in Washington. We hypothesize that marijuana use at WSU increased after RML because both the direct and social costs of using went down. RML increases the availability of marijuana for those 21 and older, and likely for those under 21 as well. It is expected that RML lowers the price of marijuana , increasing demand. Legalization eliminates the threat of punishment to legal-age users, and sends a strong message about changing norms, lowering the social costs of marijuana use. Also, Moreno, Whitehill, Quach, Midamba, and Manskopf find that legalization may have caused some Washington college students to perceive marijuana as safer. The first indication that marijuana use may have changed in Washington after Initiative 502 is observed in the trend of reported marijuana use. Fig. 1 shows the proportion of students who reported using marijuana in the past 30 days across years. For comparison, we also include the proportions over time of students who reported using tobacco, alcohol, or illegal drugs other than marijuana.

To facilitate comparisons, proportions for use of each substance are presented as deviations from the 2012-use levels. We observe a substantial increase over a general upward trend in marijuana users after 2012. Use of the other substances does not show a similar increase. More rigorously, we test for changes against a linear trend in the reported use of marijuana at WSU after RML at the end of 2012 and after legal sales began in Pullman in October 2014. We find that the probability of having used marijuana in the past 30 days increased after RML and remained high though did not increase significantly again after the first marijuana stores opened. We also test for these same changes within specific subgroups of the population. First, we compare the change in use for legal-age students to those under 21, who are not directly affected by RML. We find that for those under 21, the probability of using marijuana increased both after RML and after legal sales began. For students age 21 and over we find no increase at either juncture that is statistically significant at conventional levels. Among other subgroups, we find consistent evidence of an especially large increase in the probability of use for females and for Black and Hispanic students . RML may also affect the use of tobacco, alcohol, or other drugs, either as a substitute or complement. Moreover, factors other than RML that affect marijuana use likely also change the use of other substances. We find no evidence for any systematic changes in the use of other substances that correspond directly with the changes in marijuana use after RML. We are also interested in the intensity of marijuana use, so we test whether the average frequency of marijuana use increased after RML or legal sales. These results show the intensity of marijuana increased after RML, but decreased again after legal sales commenced. Data limitations prevent us from including a reliable control group in the regressions.2 Thus, the estimated effect of RML from the above tests represents the actual treatment effect of RML only to the extent that the linear trend is a good proxy for what marijuana use would have been like without RML. We provide an alternative evaluation by comparing marijuana use at WSU to two national datasets. Although we are unable to include any co-variate controls in the national data after 2011, we calculate simple difference-in-differences estimations of the impact of RML at WSU using two national samples as counterfactuals.We use repeated cross-sectional data of undergraduate students at Washington State University , collected for the National College Health Assessment , a comprehensive health survey collected and made available by the American College Health Association.

WSU has participated in the NCHA in seven different survey years: 2005, 2006, 2008, 2010, 2012, 2014, and 2015. The total number of survey responses available is 14,485, with a mean of 2,069 students surveyed each year. Participants were randomly selected from the student population for all survey years except for 2012 and 2014; in those years, invitations were distributed to the entire student population. After eliminating observations for missing values, our sample contains 13,335 observations. The first column of Table 1 shows the number of students in each year of the WSU sample. The distribution of surveys across years for the excluded observations is nearly identical to the distribution for the whole sample. The NCHA surveys contain questions about students’ use of marijuana, tobacco, alcohol,cheap grow tents and other drugs. Our main variable of interest is a count of how many times a student used marijuana in the past 30 days. For tests 1 and 2, this variable is modified into a binary indicator of whether a student used marijuana at all in the past 30 days. Variables included as controls in our regressions include age, sex, race, and year in school. In other specifications, we also include respondents’ grade point average , type of residence, membership in a fraternity or sorority, and whether a student is international or if they have used tobacco, alcohol, or illegal drugs other than marijuana in the past 30 days. Table 2 provides summary statistics for these variables.Also included in this table are mean values for all variables both before and after the passage of Initiative 502, and summary statistics for the same variables in the national sample of NCHA data and in the NSDUH sample as available. The student population at WSU is about 53-percent male, 68-percent white, 3-percent Black, 5-percent Asian, 10-percent Hispanic, and 5-percent international. The distribution across years for undergraduates is about 23-percent first-year, 23-percent second-year, 24- percent third-year, and 31-percent fourth-year or more . The average GPA for students is about 3.08 . In 2014, the average age across all six campuses was 23 for undergraduate students .

Between 2013 and 2015, 21- to 24-percent of undergraduate students were in fraternities or sororities . Because the cited WSU population statistics are measured after 2012, we compare the NCHA sample statistics to the WSU population for observations after 2012. It appears that the NCHA sample is representative of the WSU population, except for an oversampling of white and Asian students and an under sampling of male and older students. In the NCHA surveys, students are encouraged to select all races that apply to them, which may explain the oversampling of white and Asian students.WSU population data for race is available from 2009 and the NCHA sample closely matches with respect to trends in race composition over time. specifically, the proportion of white students decreases, Black and Hispanic students increase, and Asian students remain constant since 2009. The average age of students in the NCHA sample is lower in part because it only includes students from the Pullman campus, which is WSU’s main undergraduate campus. Finally, there is a small difference in the proportion of male-to-female students in the sample, though this proportion is consistent before and after RML. For difference-in-differences calculations, we use two national-level data sources on marijuana use. First, we use a national sample from the NCHA survey beginning in 2005 that contains surveys from the spring and fall of each year until 2011 and from only fall in 2012 and 2013. Only schools that survey a random sample of students are included in the national dataset. According to the ACHA, the NCHA’s national data is reliable, valid, and suitable for use as a national reference group . We also use data from the National Survey on Drug Use and Health for 18–25-year-old college students from 2005 to 2015. Both national samples contain the same measures as the WSU sample for whether and how many times a respondent had used marijuana in the past 30 days. To more closely match the WSU sample, observations are excluded from the national samples that have missing values for any variables matching those included in the regressions. Table 1 displays the number of students, the number of schools, and the average number of students per school in each year of the national NCHA sample and the number of students in each year of the NSDUH sample. The difference-in-differences calculations are only a valid estimate of the effect of RML to the extent that the national data is a sufficient counterfactual to what we would see at WSU in the absence of RML. We evaluate the extent to which the WSU sample matches the national samples in the pre-RML period by first comparing the means in Table 2.

Voxel-wise statistics were corrected at the cluster-level using Threshold-Free Cluster Enhancement to a Family-Wise Error rate of p b 0.05, with 5000 permutations. Nevertheless, as a further control for heritability, we conducted follow-up analyses by randomly selecting one user from each family such that there were no siblings within the sub-sample, resulting in 272 marijuana users. Identical analyses were performed using the full user sample and the unrelated sub-sample. These analyses were conducted using FSL’s randomise package, which performs permutation methods, without using exchange ability blocks. Following the PALM analyses, 5000 permutations were performed. Likewise, voxel wise results were corrected using Threshold-Free Cluster Enhancement to a FWE-corrected p b 0.05.We further processed the pre-processed diffusion images using FSL’s FDT toolbox and Tract-Based Spatial Statistics . Briefly, the diffusion tensor model was fit at each voxel yielding maps for fractional anisotropy , axial diffusivity , radial diffusivity , and mean diffusivity . These maps were then nonlinearly aligned to the FMRIB 1 mm FA template and skeletonized. This last step creates a skeleton which represents the centers of all fiber bundles that are generally common to all participants in the study. The skeleton was thresholded at FA b 0.3. The skeleton and nonlinear registration parameters were generated using the FA maps, and these transformations were subsequently applied to the other diffusion parameter maps. Voxel-wise statistics were then performed in this skeleton space.The effect of marijuana use on white matter was assessed with a linear parametric analysis across level of marijuana use. Participants reported a wide-range of levels of marijuana use in terms of age of first use as well as the number of times used over the lifetime, as shown in Fig. 1. Age of first use and times used were included as factors of interest and, as described above, all analyses included alcohol and tobacco use, age, gender, years of education, and Total Motion Index as co-variates. For a table of correlations between all co-variates see Table 1.Analyses of voxel wise gray matter morphometry were carried out with FSL-VBM an optimized VBM protocol carried out with FSL tools . First, structural images were brain-extracted and gray matter-segmented before being registered to the MNI 152 standard space using non-linear registration.

The resulting images were averaged and flipped along the x-axis to create a left-right symmetric,trimming tray study-specific gray matter template. Second, all native gray matter images were non-linearly registered to this study-specific template and “modulated” to correct for local expansion due to the non-linear component of the spatial transformation. The modulated gray matter images were then smoothed with an isotropic Gaussian kernel with a sigma of 3 mm. Finally, voxel wise GLM was applied using permutation-based non-parametric testing, correcting for multiple comparisons across space, using Threshold-Free Cluster Enhancement . Following Weiland et al. , we also performed a multivariate analysis on the effects of marijuana use on sub-cortical and cortical volumes and cortical thickness extracted with FreeSurfer.Rather than analyzing whether marijuana showed a multivariate effect across all 35 cortical regions contained in this table as did Weiland et al. , we chose an a priori approach, focusing on prefrontal regions and sub-cortical regions where marijuana has been shown to have significant effects . Regions of interest included 15 prefrontal cortical regions : medial and lateral orbitofrontal cortex, caudal anterior cingulate, caudal middle frontal, inferior frontal gyrus , rostral middle frontal, superior frontal, and frontal pole. Subcortical regions included nucleus accumbens, hippocampus, cerebellum cortex and white matter, thalamus, and amygdala. White matter volumes were included for the anterior and mid anterior corpus callosum.Shape analyses of sub-cortical ROIs were carried out using FSL’s FIRST tool . FIRST allows for a model-based segmentation and registration of anatomical images, where volumetric labels are parameterized as surface meshes.Vertex locations from each participant were projected onto the surface of the average shape , resulting in scalar projection values. This approach normalizes for brain size.

The same models of marijuana use generated for the white matter analyses were used here. Again, PALM was used to perform multi-level block permutation analyses. In order to identify which, if any, sub-region of the hippocampus, amygdala, or nucleus accumbens exhibited a shape difference, we referred to the Jülich histological atlas contained in FSL. Because FIRST only reports changes at the surface of the structure and does not contain information about which deep levels of a structure are impacted, these sub-region labels represent approximations.We then examined the effects of marijuana use on white matter diffusion parameters . The group comparison showed no significant effects, possibly suggesting that the frequency of marijuana use in the HCP sample is not severe enough to replicate previous studies, which largely focused on comparisons of non-users and daily marijuana users. In line with this possibility, there were no linear effects of the number of times used on white matter coherence in users. As shown in Fig. 2, age of first use had a positive association with FA as well as a negative association with RD, such that an earlier age of first use was associated with lower FA and greater RD in a large cluster of right hemisphere white matter. These tracts primarily subsisted of the Superior Longitudinal Fasciculus , Inferior Longitudinal Fasciculus , and Forceps Major and Minor. The SLF connects the prefrontal cortex and parietal cortex and is involved in executive functions , and the ILF connects the temporal and occipital cortices, has been shown to affected byadolescent marijuana abuse . The Forceps Major and Minor are extensions of the corpus callosum connecting the left and right occipital and frontal lobes, respectively. Thus, even though most of the effects on FA and RD were found in the right hemisphere, communication between the left and right hemispheres may be impacted by marijuana age of onset.When examining the subset of unrelated marijuana users, we confirmed the negative effect of an earlier age of first use on FA and RD in the SLF, as shown in Fig. 3. Increased RD has been related to demyelination in neurodegenerative diseases such as multiple sclerosis , suggestive of a neurotoxic effect with early age of first use of marijuana. These findings taken together, and in line with previous studies , suggest that an earlier age of onset is associated with decreased coherence of white matter. Moreover, these results suggest that marijuana use has an impact on the development of these white matter tracts during adolescence.We then investigated whether the shape of the hippocampus, amygdala, or accumbens was impacted by marijuana use. For the full sample of users, the results are shown in Fig. 4. There was a trend for a significant negative relationship between the number of times used and scalar values in the left amygdala .

Participants with a higher number of times used showed more inward deflection in the superficial group of the left amygdala. In the right nucleus accumbens, there was a significant positive relationship between age of first use and shape, such that participants with an earlier age of onset of use showed greater outward deflection. This finding suggests that a later age of first use is related to more outward deflection of the right anterior nucleus accumbens. In the left hippocampus cornu ammonis and posterior hippocampus subiculum, a greater number of times used was associated with greater inward deflection . The effects of the number of times used marijuana in the restricted sample closely mirrored those in the full sample. In the left superficial amygdala there was a trend for participants with a higher number of times used to show more inward deflection . Likewise, the same pattern was observed in the left hippocampus cornu ammonis . For age of first use, however, there was the opposite pattern , albeit in the left posterior nucleus accumbens , suggesting that a later age of first age is associated with a more inward deflection of the left posterior nucleus accumbens. This latter finding is similar to that observed by Gilman et al. who found that more frequent use was associated with an inward deflection of the nucleus accumbens. When comparing users and non-users,trim tray pollen significant effects on shape were discovered in the right amygdala and left hippocampus. There were two clusters in the right amygdala, one in the dorsal superficial group and another in the ventral laterobasal group, that showed more outward deflection in users compared to non-users. Similarly, in the left ventral anterior hippocampus , users showed more outward deflection compared to non-users. This region was more ventral and anterior to the cluster in the subiculum that showed a negative association with times used in users. These group results are somewhat surprising, as the correlational analyses within users showed inward deflections in more heavy users. However, the left and right nucleus accumbens also showed opposite patterns of inward and outward deflections with greater use, respectively. Thus, one possibility is that marijuana has differential effects in the left and right hemispheres. Nevertheless, Gilman et al. found more inward deflections for heavy users in both left and right nucleus accumbens and the right amygdala.Despite a trend of de-criminalization and softening societal views, the scientific literature on the effects of marijuana on the brain has not yet reached a consensus. Work with adolescents has consistently shown that heavy marijuana use leads to disruptions in the integrity of white matter . However, work investigating the effects of marijuana on the morphometry of gray matter and sub-cortical regions has yielded inconsistent findings, with several papers even providing strong evidence that heavy marijuana has no effects on brain morphometry . The current study took a broad look at this question using a multi-modal neuroimaging approach on data from almost 500 participants reporting varying levels of recreational marijuana use. These data from the HCP include the highest quality neuroimaging data publically available, with almost twice the resolution for structural images , and using state of the art diffusion imaging . This large dataset enabled us to investigate parametric associations between marijuana use and cortical and sub-cortical brain morphometry and white matter integrity. An advantage of this dataset is that it represents a representative community sample, with great variability in race,ethnicity, gender, education level, mental health symptoms, and drug use . Moreover, such ‘big data’ sets like the HCP are becoming more and more commonplace , and it will be important to mine these datasets to discover new insights about the functions and organization of the human brain. Importantly, this data set provided information on age of first use providing information on whether or not use occurred during early adolescence. Adolescence is a time of critical brain development for white matter tracts, with white matter volume increasing into young adulthood . Heavy marijuana use during this critical period may impact development , and specifically, a number of frontal and association white matter tracts show decreased white matter integrity with heavy adolescent use. Recently, Becker et al. found that over the course of two years, young adults with an adolescent onset of marijuana use showed reduced longitudinal development of FA in key frontal, central, and parietal white matter tracts. The current findings are largely consistent with those reports. We found that an earlier age of first use was associated with decreased FA and increased RD in long-range tracts including the forceps minor, Superior Longitudinal Fasciculus, and Inferior Longitudinal Fasciculus. Given that the average age of participants in the current study was 29.2, the effects of marijuana on white matter appear to be long lasting, persisting 10–20 years after the first use of marijuana. Future, studies should examine the effects of duration of use on the trajectory of brain development. With regards to shape, a recent meta-analysis has suggested that the sub-cortical structure most consistently implicated in showing an effect of marijuana use is the hippocampus . Consistent with that finding, we observed that anterior aspects of the hippocampus showed shape differences due to the number of times marijuana has been used. This finding is interesting as anterior and posterior sub-regions of the hippocampus have dissociable roles in memory, with the anterior portion being involved more in memory encoding and the posterior portion being involved more in memory retrieval ; however, an exploratory analysis revealed no connection between hippo-campal or amygdala shape and memory performance in these participants .

In recent years,however,the public health policy regarding marijuana legalization has been swiftly changing in the United States.As of April 2018,nine states – Alaska,California,Colorado,Maine,Massachusetts,Nevada,Oregon,Vermont,and Washington – and the District of Columbia have enacted laws to authorize the production,distribution,and possession of marijuana.A total of 29 states and DC have allowed medical use of marijuana for patients with approved health conditions.States with medical marijuana laws have an evident form of patient registry,and they provide protection against arrest for possession up to a limited amount of marijuana for medical use.In the U.S.,marijuana legalization may be one of the most controversial issues including legal,policy,health,and economic considerations.For example,marijuana legalization has been a highly contested public health issue between state and federal drug laws.Also,the essential question may be whether marijuana has medical value.The national controversy over marijuana legalization has included discussion of both the benefits and risks of non-medical marijuana use.Additionally,it is important to consider economic effects of marijuana legalization.Communication researchers have examined how the news media can influence public perceptions or attitudes toward certain issues by using the notion of framing.According to Gamson and Modigliani,a frame refers to a key organizing theme or idea that provides meaning to issues or events reported in a news story.A frame is an idea organizer that packages an issue in a specific way,telling what the issue is about.Media frames suggest how the public can interpret an issue or event,and framing involves selection and salience.Thus,news framing can influence the public’s perceptions about public health policy including marijuana legalization.

Drugs have been described mainly as objects of government enforcement and negative connotations of use in the mainstream news outlets.In the issue of marijuana legalization,roll bench a variety of organizing themes can be presented.For example,a marijuana legalization story can be framed as a legislation issue,in which news stories primarily emphasize the legislative proceedings regarding marijuana use and marijuana legalization.Previous studies have explored how American news media frame the marijuana policy,including medical use of marijuana and recreational use of marijuana.Analyzing newspaper articles between June 2008 and June 2009,Vickovic and Fradella found that U.S.newspapers mainly discussed medical marijuana as legal and regulatory issues and passage of medical marijuana news.Although it is very prominently discussed in terms of public health,legal,policy,and economic perspectives,researchers had paid little attention to how the media presented this issue.In order to reduce the gap in the literature,we make an attempt to comprehensively investigate media frames about marijuana legalization.First,we examine the organizing theme of marijuana legalization stories.More specifically,this study investigates how U.S.newspapers present the issue of marijuana legalization from 1995 to 2014.Also,we look at whether the frequency of organizing themes remains steady or not over time.As a recent survey shows,public opinion on legalizing marijuana has dramatically changed.Second,we explore the tone of each news article.specifically,this study examines how the tones of marijuana legalization are presented and changed over time between 1995 and 2014.Coleman et al.suggest that story tone assumes affective perspective,providing the story a positive,neutral,or negative connotation.affective attributes consider audience’s emotional responses to media stories.Examining the tone of ethanol stories in U.S.newspapers,for example,Kim et al.categorized story tone into pro-ethanol,anti-ethanol or neutral.They found that 48% of stories described a bio-fuel issue as neutral.In this study,the story tone refers to answering the question of whether the story is overall in support of or in opposition to marijuana legalization.

Additionally,the political orientation of news outlets has been considered as a major factor that can influence the tone of news stories.Thus,it can be predicated that liberal newspapers tend to describe marijuana legalization with a positive tone more often than conservative newspapers.To select newspapers from both states where marijuana is allowed and illegal,we analyzed a total of 10 newspapers published in the United States.Considering the location,circulation,and political orientation of newspapers,three categories were selected for analysis: national newspapers,newspapers in states where marijuana is illegal,and newspapers in states where medical marijuana is legal.These newspapers were available at the search databases.According to the 2008 and 2012 presidential endorsements,liberal newspapers include the New York Times,the Washington Post,the Denver Post,the Seattle Times,and the San Francisco Chronicle,while others are conservative newspapers.News articles were retrieved using a key word search of three search engines: the Lexis-Nexis,the News Bank,and the Factiva databases.The keywords “medical marijuana” OR “marijuana use” OR “marijuana legalization” OR “legal marijuana,” appearing in the headline or the lead paragraph of the Lexis-Nexis database,in the lead or first paragraph of the News Bank database,and in the text of the Factiva database were used to find articles of coverage selected for this study between 1995 and 2014.This search yielded a total of 4186 articles – including editorials – from the 10 newspapers,and we produced a manageable systematic random sample of about 75 articles from each paper.This study excluded unrelated stories where marijuana was simply mentioned without being the main focus or where reported marijuana related crimes.After excluding these unrelated articles,a total of 640 articles were analyzed.The coding instrument was developed through a comprehensive review of news stories and previous studies.

Coding was conducted by one of the authors and one graduate student.Coders first read a story carefully,and then decided an organizing theme of each story by examining what was the main focus.Because researchers paid little attention to examining news frames of marijuana legalization,more than 100 news articles were carefully reviewed to find out organizing themes in stories related to marijuana legalization and medical marijuana.Then,six organizing themes were identified after examining marijuana legalization stories and previous studies.Each story was categorized into one of the six organizing themes: legislation,law enforcement,youth drug use,economy,patients,and medical effects.When coders found more than two themes in an article,they checked both.The description of organizing themes is presented in Table 1.Coders then coded overall tones of a story.This study used the way to indicate overall tones examined by the previous studies.Coders first decided that each paragraph was positive,neutral,or negative toward medical or recreational use of marijuana.There were three major considerations to examine: what was emphasized in the headline and lead,how the balance or imbalance of the pros and cons of marijuana use were described,and how the metaphor mentioned in each story were related to positive or negative social norms.Coders then decided story tone as an ordinal category by classifying 1 to a negative,2 to a neutral,or 3 to a positive story.When at least two-thirds of the paragraphs could be considered as either negative or positive,coders selected one of either category.Otherwise,the story was coded as neutral.Two coders coded articles after having conducted a series of training and pilot-test sessions.Intercoder reliability was calculated by double coding a random sub-sample of the data.Intercoder reliability corrected for agreement by chance ranged between 0.79 and 1.00 with an average reliability of 0.88.This study aims to answer the question of how U.S.newspapers have presented the issue of marijuana legalization between 1995 and 2014.Newspapers have largely described marijuana legalization as a law enforcement issue rather than an economic issue or a medical issue.Taken together,our findings are consistent with previous studies that have revealed that marijuana has been mainly discussed as a legal and policy issue.Framing can affect the way the readers evaluate a certain issue,influencing their judgment.Thus,it can be argued that Americans are more likely to evaluate marijuana legalization as a public policy issue,rather than a public health issue.There can be several explanations for these findings.First,marijuana legalization is essentially the theme about the legislative acts.A number of legislative measures that allow for recreational use of marijuana have been passed since 2012.Second,marijuana stories often involved conflicts between federal and state governments,between enforcement agencies and citizens,and between governors and congresses.

The conflict perspective is a popular frame because conflict is a recognized news value.Thus,this conflict may influence journalists to report marijuana stories as a law enforcement theme.Third,a medical effect theme and a patients theme might appear less often because we examined stories related to recreational use as well as medical use.Nonetheless,criticism of newspapers’ tendency to define marijuana stories as legislation or law enforcement stories may be justified.Because these themes were clearly dominant,the issues surrounding medical marijuana were not commonly highlighted in the news.Although the issue of marijuana is important in terms of public health approach,our findings indicated that journalists paid little attention to the medical effect theme when covering marijuana stories.Our findings also revealed that organizing themes appeared differently according to the presidential periods.First,newspapers frequently described marijuana stories with a legislation theme during the Obama administration period.Since Colorado and Washington initially allowed for recreational use of marijuana in 2012,other seven more states have followed.As Griffin et al.pointed out,the passage of drying rack cannabis laws significantly increased news stories.During this period,frequent legislative activities caused media attention.Second,an economy theme more frequently appeared since 2009.Block also found that marijuana legalization was discussed mainly as a business issue in 2014.In particular,many news stories reported the expected and actual economic effects of legalization during those years.Third,a youth drug use theme peaked during the first Clinton administration period,and then it has decreased.Interestingly,according to Monitoring the Future survey,the actual use among youth was somewhat declined between 1995 and 2008.Thus,newspapers probably reflected this trend.Although more than half articles described the issue of marijuana with a neutral tone,positive stories were published more frequently than negative stories.These findings can be explained by two-sided framed stories,which often result in a neutral tone.As Sniderman and Theriault indicate,the public should make choices between several competing values in real politics.In a two-sided frame,a story presents both frames of an issue.For example,the media may present reasons to both support and oppose marijuana legalization in the same story.Over the past decade,the political discourse around marijuana legalization has been dominated by competing frames over the legal,law enforcement,economic,and public health consequences of proposed state and federal government policies.These two-sided or non-framed articles likely present the issue with a neutral tone.Our findings have several limitations.First,we examined only newspapers.If marijuana stories were retrieved from other sources for 20 years,1995 to 2014,it could be very hard to manage the sample.Thus,one of the major reasons to analyze only newspapers was to obtain a manageable sample size.Also,newspapers still provide a useful channel to deliver information,as they can play a key role in setting the agenda for other news media.

In addition,many mainstream newspapers have provided their online versions through their own web pages and social media.Thus,news stories from these newspapers can be widely exposed to Americans.Future research should include other news sources.Second,the selection of newspapers has limitations.Because some newspapers were not available through online search engines,we examined less representative newspapers,which can cause concerns regarding the generalizability of the findings.Thus,it is necessary for future research to include more representative newspapers as much as possible.Third,it can be pointed out that the categories of themes were inductively determined because there have been only a few previous studies on the topic of marijuana legalization.The coding categories used in this study may raise questions about the results in terms of validity and reliability.Thus,future studies should test the same categories that this study used and then develop more correct coding categories.Lastly,the time period for this study was between 1995 and 2014.Although marijuana was initially legalized in 2012,the first recreational sales were in 2014.Thus,news stories during 2014 could be quite different than stories from previous years.The development of high-performance materials made from natural resources is increasing worldwide due to their abundant source in the nature,low cost,light weight and high specific modulus in contrast to the synthetic fibers.In addition,they are biodegradable,renewable,have low specific weight,high specific strength and stiffness than glass fibers,ease of processing,reduced wear,good thermal and acoustic insulating properties.Hemp fiber is recently gaining attention as diversified reinforcing applications in composite industry,housing,railways and aerospace applications due to its high specific strength and stiffness.Hemp offers excellent mechanical strength and Young’s modulus.However,the foremost limitation of natural fibers used as reinforcement is the poor interfacial adhesion between polar hydrophilic natural fibers and non-polar hydrophobic polymers.Different coupling agents have been used to increase compatibility between natural fibers and thermoplastic matrices,thereby augmenting the composite’s performance.The increasing use of polyethylene in number of applications is posing a serious environmental threat and thus the researchers are motivated to undertake studies concerning recycling of polymer waste.The literature consulted so far reveals that the studies pertaining to mechanical characterization of hemp fiber reinforced polyethylene composites,especially containing recycled PE,are rather scant.In the light of these facts,it is decided to investigate the mechanical behavior of hemp fiber-recycled PE composites.