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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Canadian Cannabis: Orthodoxies of Exclusion and Access / ORTHODOXIES OF EXCLUSION AND ACCESS

McCann, Clayton January 2023 (has links)
The dissertation that follows is the result of extended collaboration with, and co-labouring among women working in an illicit, value-added cannabis production facility, 400115335 BC, in the southeastern interior of British Columbia, Canada, in the lower Slocan Valley. An extended case study of the political economy leveraged against these workers ensues, which exposes the mechanisms depriving them of state provisions and protections normally afforded to Canadian citizens. Illegal firms employing unprotected workers, with the full consent of local and provincial authorities, represent the significant findings of this research. Further, the work engages in ethnographic content analysis to evaluate the intentional exclusion of illicit cannabis producers in the West Kootenay region, and in Canada more generally, from the approvals and licenses that would permit them to participate in legal markets. An examination of late capitalist financialisation is presented to illustrate that ex-politicians and law enforcement persons prioritised their personal access to cannabis production licenses and markets over that of a five decades-old, established industry, excluding hundreds of functioning production farms, opting instead to create cannabis production firms incapable of producing at scale, many of which either engaged, or continue to engage in malfeasant practices such as deployment of the deceptive IFRS accounting methodology, the over-compensation of corporate principals, and the “pump and dump” stock valuation scam, a form of insider trading. / Dissertation / Doctor of Philosophy (PhD) / The dissertation that follows is both a result of co-labouring among workers in an illicit, value-added cannabis production facility in the south-eastern interior of British Columbia, Canada, and an ethnographic content analysis that takes as its subjects the intentional exclusion of Canadian small-scale, craft cannabis farmers, the ‘natural/rational’ cannabis market Canada created when it legalized the substance in late 2018, and the access granted to that market for powerful politicians and law enforcement officials. An investigation of the political economy leveraged against illicit workers ensues, depriving them of state provisions and protections normally afforded to Canadian citizens. Legal firms engaging in fraudulent financial activities, and illegal firms employing unprotected workers, within the purview and full consent of authorities, represent significant findings.
12

A study of infraspecific flavonoid variation of Cannabis sativa L. (Cannabaceae)

Clark, Murray Nelson January 1978 (has links)
The genus Cannabis has been treated taxonomically by several authors, but two main hypotheses predominate. Small and Cronquist (1976) concluded that the genus is monotypic and contains only Cannabis sativa L. Subspecies were named according to the economic purpose of the plants, i.e. fibre or drug, and varieties were assigned according to habitat (wild or cultivated). Schultes (1974) believed the genus is polytypic, with Cannabis sativa L. representing the fibre plants, C. indica Lam, the drug plants, and C. ruderalis Janis. the wild and weedy plants. A study of flavonoid variation was undertaken to determine which of the taxonomic schemes would be supported by this variation. Individual plants were examined by thin-layer chromatography and presence/absence data for nine flavonoids were analyzed by three types of computer programs. The infraspecific variation of flavonoids in the genus Cannabis supports the monotypic theory of Small and Cronquist (1976). No consistent, distinguishable groups were noticeable in the data. Wild taxa were more closely related to their cultivated progenitors than they were to each other. A division of the genus Cannabis into several species would not be supported by flavonoid variation. / Science, Faculty of / Botany, Department of / Graduate
13

Reform of minor cannabis laws in Western Australia, the United Kingdom and New Zealand /

Swensen, Greg. January 2006 (has links)
Thesis (LLM (Research))--Murdoch University, 2006. / Thesis submitted to the Division of Arts. Bibliography: leaves [228]-272.
14

Production du cannabis médical (Cannabis sativa L.) cultivé en hydroponie : impact de N, P et K sur la croissance, productivité et qualité

Leblanc, Camille January 2022 (has links)
Le cannabis médical et récréatif (Cannabis sativa L.) est une industrie en pleine expansion au Canada depuis sa légalisation en octobre 2018. Cependant, le peu de connaissance scientifique sur la fertilisation est un enjeu important pour les producteurs afin d'obtenir de meilleurs rendements et d'offrir un produit de qualité. Cela se traduit souvent par une fertilisation excessive ou non adaptée à cette espèce, ce qui impacte la qualité des produits et engendre des coûts plus élevés de production. Le but de cette étude était donc, dans un premier temps, de caractériser les taux de prélèvement des éléments nutritifs du Cannabis sativa lors de la phase de floraison et, dans un second temps, de déterminer pour un génotype l'effet de N, P et K sur la croissance, la productivité et la qualité des inflorescences. Pour ce faire, nous avons réalisé deux expériences. La première expérience s'est déroulée chez un producteur autorisé (IsoCanMed Inc.) utilisant des tours verticales aéroponiques et où deux doses de N (150 et 250 ppm) ont été comparées et l'absorption minérale des plantes caractérisée au cours de la phase de floraison, et ce, pour 2 cycles de production par niveau d'azote. La deuxième expérience s'est tenue dans une serre de l'Université Laval et a permis d'étudier les effets de cinq concentrations de P (25, 50, 100, 150 et 200 ppm) et deux concentrations de K (175 et 250 ppm) pour des plantes cultivées dans un système hydroponique en eau profonde. Nos résultats ont démontré qu'une concentration élevée en N (> 150 ppm) a entrainé une surcroissance des plantes (hauteur des plantes), a diminué la teneur en THC des inflorescences (-9,5%), mais a permis d'augmenter la biomasse florale (+29%) d'un des deux génotypes étudiés. Des concentrations supérieures à 25 ppm de P et 175 ppm de K n'ont toutefois pas amélioré la productivité et la qualité des inflorescences. Les résultats obtenus ainsi que la caractérisation des taux d'absorption des éléments nutritifs au cours du développement de la plante nous ont permis de suggérer une fertilisation de référence en N, P et K pour des plantes en phase de floraison et cultivées dans un système hydroponique. Il serait toutefois intéressant de poursuivre ces travaux avec un plus grand nombre de phénotypes et sous différentes conditions lumineuses. / Drug-type cannabis (Cannabis sativa L.) in a booming industry following its legalization in Canada in 2018. However, few scientific studies on the optimal fertilization is a main challenge for producers who aim to harvest high yields with a high cannabinoid content. Thus, this often results in the overuse of fertilizers or not well adapted fertilization that impact the quality and the cost of production. Thus, the aim of this study was to characterize the nutrient plant uptake during the flowering phase and to determine the impact of N, P and K on growth, productivity, and quality of the inflorescence. The first experiment was done within a plant factory at a licensed producer (IsoCanMed Inc.) who uses vertical aeroponic towers. Two levels of N (150 and 250 ppm) were used in two cycles for each treatment to identify their impact on Cannabis and to characterize the nutrient uptake throughout the flowering phase. The second experiment was conducted in a greenhouse located at Laval University in order to test five (25, 50, 100, 150 and 200 ppm) and two (175 and 250 ppm) concentrations of P and K, respectively, by using a deep-water system. Based on our results, N fertilization above 150 ppm resulted in an overgrowth (plant height), a reduction in THC content in the inflorescences (-9.5%), but an improvement in floral biomass productivity (+29%) for one genotype. Concentrations above 25 ppm P and 175 ppm K, however, did not improve the productivity and the quality of the inflorescences. The results obtained as well as the characterization of the absorption rates of nutrients during the development of the plant allowed us to suggest a reference N, P and K fertilization for flowering plants grown in a hydroponic system. However, it would be interesting to continue this work with a larger number of phenotypes and under different light conditions.
15

Cognition and cannabis use disorder in recreational cannabis users and medical cannabis patients

Sagar, Kelly A. 29 May 2020 (has links)
As legalization of cannabis continues to spread across the United States, many question the public health implications. The term “cannabis” is often used to refer to anything that comes from the plant and can be used recreationally (to get high or alter one’s current state) or medically (to treat a medical condition). While previous research has primarily focused on the impact of recreational cannabis use, few studies have examined cognitive outcomes associated with medical cannabis (MC) use and the potential for development of problematic use in MC patients. Given important distinctions among recreational users and MC patients, it is likely that these distinct populations of cannabis consumers will experience differential cognitive effects and potential for problematic cannabis use. This dissertation is comprised of three studies. The first is a cross-sectional study that explores executive function and verbal learning and memory in recreational cannabis users relative to healthy controls who do not use cannabis, while also assessing whether cannabis use patterns (e.g., age of onset, urinary THC levels) influence findings. The second study is an observational, longitudinal study which examines executive function and memory, as well as changes in mood, anxiety, sleep, and quality of life in MC patients over 12 months of MC treatment relative to pre-MC treatment. In the third study, symptoms and behaviors associated with problematic cannabis use are examined in cohorts from study 1 and study 2. Specifically, scores on the Cannabis Use Disorder Identification Test – Revised (CUDIT-R) are assessed in MC patients over the course of treatment and also compared to a previously recruited cohort of recreational cannabis users; the validity of the CUDIT-R is also explored. Despite previous research, in the current study recreational users did not exhibit cognitive decrements relative to healthy controls. In MC patents, cognitive performance was stable over the course of 12 months of MC treatment relative to pre-MC treatment performance, and overall they reported improved ratings of mood, anxiety, sleep, and some aspects of quality of life. Although the CUDIT-R suggests MC patients’ average scores do not meet the threshold for possible cannabis use disorder, analyses revealed this measure is not valid and therefore not appropriate in MC patients. Although changes in cognition were not detected in recreational users or MC patients in the current studies, a number of methodological limitations (e.g., sample size and limited ability to adjust for confounding variables) must be considered as these factors likely affected study results. Future studies evaluating the impact of cannabis use will benefit from carefully considering the definition of cannabis itself, goal of use, product choice, and age of onset of use. Researchers and clinicians will also benefit from the development of screening tools specifically designed to assess cannabis use disorder in those who use cannabis for medical purposes.
16

Qualitative and quantitative analysis of the cannabinoid content of combusted cannabis plant tissue

Jaeck, Aaron Michael 12 July 2007
Marihuana continues to be a controversial topic in todays society. The plant material is used recreationally as a stupefacient and has a purported medicinal use. In fact, anecdotal information about its medicinal properties has been such that Health Canada has recently started an initiative to provide a well characterized supply of plant tissue to researchers interested in examining its potential medicinal properties. Simultaneously this same material is being provided for those subjects who are licensed to use marihuana as a medicine. <p>In order to further study marihuana and its component cannabinoids it is essential to be able to discern both the cannabinoid content in the product being supplied and more importantly the cannabinoid profile in the delivery system. At present the most common route of administration is via inhalation of the combusted plant material. Consequently methods capable of measuring the cannabinoid content in combusted plant material would be very useful in order to make meaningful study of the pharmacokinetics of the cannabinoids delivered by this route. <p>Investigations were carried out to develop a method and study the volatile constituents of combusted marihuana plant material in a semi-enclosed environment. Thus the hypothesis of this research is that qualitative and quantitative information can be obtained from the combustion products of cannabis plant tissue. The method relies upon the solid phase extraction of smoke arising from the combustion of plant material in a variety of combustion chambers. The combustion chambers were designed to reflect the current marihuana paraphernalia in use as well as a high efficiency in vitro system. Both the qualitative and quantitative levels of a limited number of cannabinoids were evaluated before and after combustion. A quantitative Liquid Chromatography Ultra Violet (LC-UV) detector method was validated for the analysis of a selected group of cannabinoids ( Δ9-tetrahydrocannabinol (THC), cannabinol (CBN), cannabidiol (CBD) and tetrahydrocannabinolic acid (THCA) . When this method was applied to plant material available through the medical marijuana initiative the following observations were made on the combustion products:<p> <table style="text-align: left; width: 397px;" border="1" cellpadding="2" cellspacing="2"> <tbody> <tr> <td style="width: 119px;">Material</td> <td style="width: 59px;">CBD</td> <td style="width: 59px;">CBN</td> <td style="width: 59px;">THC</td> <td style="width: 59px;">THCA</td> </tr> <tr> <td style="width: 119px;">Analyzed</td> <td style="width: 59px;">(ug/ml)</td> <td style="width: 59px;">(ug/ml)</td> <td style="width: 59px;">(ug/ml)</td> <td style="width: 59px;">(ug/ml)</td> </tr> <tr> <td style="width: 119px;">Plant</td> <td style="width: 59px;">BLQ</td> <td style="width: 59px;">BLQ</td> <td style="width: 59px;">BLQ</td> <td style="width: 59px;">890</td> </tr> <tr> <td style="width: 119px;">Combusted</td> <td style="width: 59px;">20</td> <td style="width: 59px;">14</td> <td style="width: 59px;">420</td> <td style="width: 59px;">28</td> </tr> </tbody> </table> 5 mg plant tissue extracted using a validated HPLC-UV method <p> 5 mg plant tissue combusted in a closed combustion chamber.<p> BLQ: below level of quantification (<12.5 ug/mL)<p>These results sparked further research into the quantitative transformation of cannabinoids during the combustion process. In this regard, it was shown that THC, CBD and CBN all could be recovered at approximately a 90% ratio upon combustion However, THCA was thermally converted such that very little remains after combustion and furthermore, its degradation product, THC can only account for 50% of the THCA. The latter observation is important since there has been a prevailing thought that THCA is quantitatively transformed during combustion to THC while in fact this transformation is approximately 50%. This finding must be considered when pharmacokinetic studies are carried out using inhalation of combusted plant material as the delivery system.<p>A further finding of this research is that not all popular combustion devices yield identical quantitative cannabinoid profiles. In this regard, the simpler pipe systems result in the highest yields of heat transformed cannabinoids while the vaporizer systems have the lowest cannabinoid yields.
17

Qualitative and quantitative analysis of the cannabinoid content of combusted cannabis plant tissue

Jaeck, Aaron Michael 12 July 2007 (has links)
Marihuana continues to be a controversial topic in todays society. The plant material is used recreationally as a stupefacient and has a purported medicinal use. In fact, anecdotal information about its medicinal properties has been such that Health Canada has recently started an initiative to provide a well characterized supply of plant tissue to researchers interested in examining its potential medicinal properties. Simultaneously this same material is being provided for those subjects who are licensed to use marihuana as a medicine. <p>In order to further study marihuana and its component cannabinoids it is essential to be able to discern both the cannabinoid content in the product being supplied and more importantly the cannabinoid profile in the delivery system. At present the most common route of administration is via inhalation of the combusted plant material. Consequently methods capable of measuring the cannabinoid content in combusted plant material would be very useful in order to make meaningful study of the pharmacokinetics of the cannabinoids delivered by this route. <p>Investigations were carried out to develop a method and study the volatile constituents of combusted marihuana plant material in a semi-enclosed environment. Thus the hypothesis of this research is that qualitative and quantitative information can be obtained from the combustion products of cannabis plant tissue. The method relies upon the solid phase extraction of smoke arising from the combustion of plant material in a variety of combustion chambers. The combustion chambers were designed to reflect the current marihuana paraphernalia in use as well as a high efficiency in vitro system. Both the qualitative and quantitative levels of a limited number of cannabinoids were evaluated before and after combustion. A quantitative Liquid Chromatography Ultra Violet (LC-UV) detector method was validated for the analysis of a selected group of cannabinoids ( Δ9-tetrahydrocannabinol (THC), cannabinol (CBN), cannabidiol (CBD) and tetrahydrocannabinolic acid (THCA) . When this method was applied to plant material available through the medical marijuana initiative the following observations were made on the combustion products:<p> <table style="text-align: left; width: 397px;" border="1" cellpadding="2" cellspacing="2"> <tbody> <tr> <td style="width: 119px;">Material</td> <td style="width: 59px;">CBD</td> <td style="width: 59px;">CBN</td> <td style="width: 59px;">THC</td> <td style="width: 59px;">THCA</td> </tr> <tr> <td style="width: 119px;">Analyzed</td> <td style="width: 59px;">(ug/ml)</td> <td style="width: 59px;">(ug/ml)</td> <td style="width: 59px;">(ug/ml)</td> <td style="width: 59px;">(ug/ml)</td> </tr> <tr> <td style="width: 119px;">Plant</td> <td style="width: 59px;">BLQ</td> <td style="width: 59px;">BLQ</td> <td style="width: 59px;">BLQ</td> <td style="width: 59px;">890</td> </tr> <tr> <td style="width: 119px;">Combusted</td> <td style="width: 59px;">20</td> <td style="width: 59px;">14</td> <td style="width: 59px;">420</td> <td style="width: 59px;">28</td> </tr> </tbody> </table> 5 mg plant tissue extracted using a validated HPLC-UV method <p> 5 mg plant tissue combusted in a closed combustion chamber.<p> BLQ: below level of quantification (<12.5 ug/mL)<p>These results sparked further research into the quantitative transformation of cannabinoids during the combustion process. In this regard, it was shown that THC, CBD and CBN all could be recovered at approximately a 90% ratio upon combustion However, THCA was thermally converted such that very little remains after combustion and furthermore, its degradation product, THC can only account for 50% of the THCA. The latter observation is important since there has been a prevailing thought that THCA is quantitatively transformed during combustion to THC while in fact this transformation is approximately 50%. This finding must be considered when pharmacokinetic studies are carried out using inhalation of combusted plant material as the delivery system.<p>A further finding of this research is that not all popular combustion devices yield identical quantitative cannabinoid profiles. In this regard, the simpler pipe systems result in the highest yields of heat transformed cannabinoids while the vaporizer systems have the lowest cannabinoid yields.
18

Cannabis effects related to cutaneous sensory perception and personality measures

Libman, Eva January 1976 (has links)
No description available.
19

Chronic cannabis use and attention-modulated prepulse inhibition of the startle reflex in humans /

Kędzior, Karina Karolina. January 2004 (has links)
Thesis (Ph.D.)--University of Western Australia, 2004.
20

Análise dos critérios diagnósticos de dependência (DSM-IV) entre usuários diários de maconha / Analysis of the substance dependence criteria (DSM-IV) in daily cannabis users

Maciel, Laura de Amorim [UNIFESP] 27 February 2009 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:49:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-27 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Associação Fundo de Incentivo à Psicofarmacologia (AFIP) / Objetivo: Analisar entre usuários diários de cannabis, os sinais e sintomas da Síndrome de Dependência de Substância, tendo como referência os critérios diagnósticos do DSM-IV. Métodos: Foi utilizado o referencial qualitativo de pesquisa. A amostra intencional, de usuários diários de maconha da omunidade, foi composta por “bola de neve”. Foram realizadas entrevistas semi-estruturadas, individuais e anônimas, com base nos critérios do Manual Diagnóstico e Estatístico de Transtornos Mentais (DSM-IV). As entrevistas foram gravadas, para posterior transcrição e análise de conteúdo categorial. Resultados: Participaram deste estudo 24 pessoas (15 homens), com idades entre 18 a 49 anos. Apenas um entrevistado relatou compulsão para o uso. Os demais mencionaram planejamento do uso em suas rotinas diárias,sem identificar redução de atividades consideradas importantes. Prejuízo de memória foi citada por 17 entrevistados.Não foi relatada tolerância para a sensação de relaxamento, principal motivação para a continuidade do uso. Sintomas nos períodos de abstinência (irritação, insîonia e redução do apetite) se aproximaram mais de sentimentos de frustração e/ou dos conceitos de efeito rebote ou off-set. Apesar de apenas quatro terem preenchido diagnóstico de dependência, 16 se consideravam dependentes. Conclusões: Os critérios diagnósticos do DSM-IV podem não identificar usuários diários de cannabis como dependentes, ainda que eles se considerem. As especificidades em relação à tolerância e controle/compulsão parecem diminuir a probabilidade de preenchimento de critérios diagnósticos. / Aim: To study the DSM-IV criteria for substance dependence among daily cannabis users. Methods: A qualitative method and an intentional sample of daily cannabis users in the community were adopted in this investigation, which was conducted in Sao Paulo, Brazil. In-depth, semi-structured interviews based on the DSM-IV criteria for substance dependence were held individually. The interviews were recorded and transcribed for posterior content analyses. Results: 24 people (15 men) aged 18-49 years participated in this study. Only one participant reported compulsive use, while the others planned cannabis use through their daily routine without reducing the frequency in which engaged in important activities. Impairments on the short-term memory were reported by 17 participants. There was no report of tolerance towards the sensation of relaxation, which was claimed to be the main motivation for continued use. Symptoms during the abstinence periods (irritation, insomnia and appetite reduction) were more likely to be some frustration feeling for not being able to smoke marijuana and/or rebound or off-set effects. Despite the fact only four participants were diagnosed dependent (DSM-IV), 16 considered themselves dependent. Conclusions: The DSM-IV diagnoses criteria might not identify cannabis daily users as dependents, despite the fat that they considered themselves dependents. The specificities regarding tolerance and control/compulsion seem to reduce the probability of establishing diagnoses of dependence. / FAPESP: 06/58658-8 / FAPESP: 07/50783-0 / TEDE / BV UNIFESP: Teses e dissertações

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