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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.
321

Ekstrakcija industrijske konoplje (Cannabis sativa L.) / Extraction of industrial hemp (Cannabis sativa L.)

Drinić Zorica 16 October 2020 (has links)
<p>U okviru ovog rada izvr&scaron;eno je ispitivanje različitih procesa ekstrakcije herbe industrijske konoplje. Za ekstrakciju određenih bioaktivnih jedinjenja primenjene su klasične tehnike ekstrakcije, maceracija i Soxhlet ekstrakcija, dok su od savremenih metoda primenjene ultrazvučna ekstrakcija, mikrotalasna ekstrakcija, ekstrakcija vodom u subkritičnom stanju i ekstrakcija ugljendioksidom u superkritičnom stanju. Praćenjem uticaja ulaznih promenjivih (procesnih parametara) na odabrane izlazne promenjive (sadržaj bioaktivnih jedinjenja ili antioksidativnu aktivnost) za svaku tehniku ekstrakcije pojedinačno utvrđeni su optimalni uslovi ekstrakcije. Nakon izvr&scaron;enog poređenja odabrana je najadekvatnija tehnika ekstrakcije za pripremu tečnog ekstrakta koji će biti transformisan u suvi ekstrakt primenom metode su&scaron;enja raspr&scaron;ivanjem. Prilikom dobijanja suvog ekstrakta ispitan je uticaj različite koncentracije nosača na kvalitet ekstrakata i efikasnost su&scaron;enja. Dobijeni ekstrakti su okarakterisani u pogledu fizičkih i hemijskih osobina. Sadržaj kanabinoida u tečnim ekstraktima suve herbe industrijske konoplje ispitanih u ovoj doktorskoj disertaciji je bio u opsegu od 0,4314 mg/mL CBD-a i 0,0364 mg/mL THC-a (u optimalnom ekstraktu dobijenom maceracijom) do 1,0420 mg/mL CBD-a i 0,0430 mg/mL THC-a (u optimalnom ekstraktu dobijenom mikrotalasnom ekstrakcijom). U ekstraktima koji su nepolarnog karaktera i koji su dobijeni primenom Soxhlet ekstrakcije sadržaj CBD-a i THC-a je bio 64,40 i 2,90 mg/g, dok je primenom superkritične ekstrakcije dobijen sadržaj CBD-a i THC-a u opsegu od 76,1193 do 163,1111 mg/g i od 4,1746 do 6,5803 mg/g. Tečni ekstrakti dobijeni primenom vode i etanola kao ekstragensa bili su bogati flavonoidima i fenolima, a utvrđeno je i da imaju značajnu antioksidativnu aktivnost, dok su ekstrakti dobijeni Soxhlet ekstrakcijom i ekstrakcijom ugljendioksidom u superkritičnom stanju bili bogati lipofilnim jedinjenjima i terpenima. Ovako dobijeni ekstrakti predstavljaju visokovredne proizvode koji imaju veliki potencijal za upotrebu u farmaceutskoj industriji.</p> / <p>Various extraction processes of the aerial parts of industrial hemp were examined. From classic extractions, maceration and Soxhlet extraction were applied, while from novel methods, ultrasound-assisted extraction, microwave-assisted extraction, subcritical water extraction and supercritical carbon dioxide extraction were applied. By monitoring the influence of the input variables on the selected output variables for each extraction, the optimal extraction conditions were determined separately. After a comparison of all the extraction processes tested, microwave-assisted extraction was selected to prepare the liquid extract for spray drying. The effect of different carrier concentrations was examined during the preparation of the dry extract. The extracts obtained were characterized in terms of physical and chemical properties. The content of cannabinoids in liquid extracts of dry Cannabis sativa herba examined ranged from 0.4314 mg/mL for CBD and 0.0364 mg/mL for THC in the optimum extract obtained by maceration to 1.0420 mg/mL for CBD and 0.0430 mg/mL for THC in the optimum extract obtained by microwave-assisted extraction. The CBD and THC content in extract obtained by Soxhlet extraction was 64.4000 mg/mL and 2.9000 mg/mL, respectively, while the highest content of CBD and THC in the supercritical carbon dioxide extract was 163.11 and 6.5803 mg/g. In addition to cannabinoids, the liquid extracts obtained were rich in phenols and flavonoids, and have considerable antioxidant activity, while the extracts obtained by Soxhlet extraction and supercritical carbon dioxide were rich in lipophilic compounds and terpenes. The extracts mentioned above are high value products which have great potential for implementation in the pharmaceutical industry.</p>
322

La mémoire émotionnelle chez les patients schizophrènes consommateurs de cannabis : une étude en imagerie par résonance magnétique fonctionnelle

Durand, Myriam 03 1900 (has links)
No description available.
323

The State and Cannabis: What is Success? A Comparative Analysis of Cannabis Policy in The United States of America, Uruguay, and Canada

Cunningham, Gideon C. 02 September 2021 (has links)
No description available.
324

Gender as moderator of the relationship between impulsivity and driving after cannabis use

Wang, Yifan 05 1900 (has links)
Road traffic crashes are a serious public health problem worldwide, and human factors are the most prominent factor of accidents, affecting mostly the young adults. Past studies found that both gender and personality traits such as impulsivity are associated with risky driving, however, the interaction of these predictors is rarely addressed in the literature. To bridge the gap, the present study explores how a specific facet of impulsivity interacts with our hypothesized moderator, gender identification, leads to drug driving using a moderator analysis. We recruited participants from 17 to 35 years old possessing a valid drivers' licence via Facebook advertising. They were invited to complete a questionnaire on their socio-demographic characteristics, cannabis consumption habits and impulsivity scores. A moderator analysis is conducted to disentangle the relationship between sensation seeking, gender and driving after cannabis consumption using SPSS Process. The proposed model contains sensation seeking as an exogenous variable directly associated with driving after cannabis use, and this relationship is moderated by gender identification. The current study provides evidence that sensation seeking and gender identification are not only associated with DACU but also interact to affect driving behaviour. Implications of the study are discussed. / Les accidents routiers constituent de graves problèmes de santé publique dans le monde et les facteurs humains sont connus pour être le principal facteur d'accidents, impliquant principalement les jeunes adultes. Des études antérieures ont démontré que le genre ainsi que des facteurs liés à la personnalité tels que l'impulsivité sont associés à la conduite après consommation récente de cannabis, cependant, l'interaction de ces prédicteurs est rarement abordée dans la littérature. Pour cette raison, cette étude vise à explorer le processus par lequel une facette spécifique de l'impulsivité interagit avec le genre ou le sexe pour modérer la probabilité de prendre le volant après avoir consommé du cannabis. Des participants de 17 à 35 ans possédant un permis de conduire valide ont été recrutés à partir de Facebook par le biais d’annonces payantes. Ils étaient invités à remplir un questionnaire portant sur leur caractéristique socio-démographique, leur habitude de consommation de cannabis, ainsi que sur les composantes de l'impulsivité. Une analyse de modération a été effectuée pour clarifier la relation entre la recherche de sensations, le genre et la conduite d’automobile à l'aide du SPSS PROCESS. Le modèle proposé inclut la recherche de sensations comme variable exogène directement associée à la conduite après la consommation du cannabis, et cette relation est modérée par le genre ressenti. Effectivement, le genre ressenti des participants semble être une variable modératrice de l’association entre la recherche de sensation et la prise de volant après avoir consommé du cannabis. Les implications de ces résultats seront discutées.
325

Självmedicinering med cannabis för posttraumatiskt stressyndrom. En normanalys av individers upplevelser och professioners uppfattning

Hyllengren, Annika, Kristiansson, Malin January 2015 (has links)
The purpose of this study was to examine people's experiences of self-medication with cannabis in relation to post-traumatic stress disorder and professions’ opinions of cannabis for medical use. The study focuses on norms and values as well as its impact on individuals. A qualitative approach was used with thematically open interview questions, in order to gain an insight into the interviewees’ reality and their experiences. Selected theories emphasize on norms, social control and gateway. The study has chosen to point out Sweden's drug policy attitudes to cannabis, research on cannabis as a complement to post-traumatic stress disorder, resources and therapies in the section earlier research. The results showed patterns of how the social control and norms affect the individual who chooses to deviate from the prevailing norm. The informants who have chosen to self-medicate cannabis in relation to post-traumatic stress disorder describes itself countered in their experiences with emotions such as contempt, exclusion and being misunderstood. It also emerged that there is transparency in the professions to the possibilities of cannabis as medicine, at present, it is a lack of evidence and research. It was also found that the informants who self-medicated strives cannabis as medicine in the market, controlled dosage.
326

Riskfaktorer hos unga som använder cannabis. Med fokus på kön och psykisk ohälsa : En jämförelse mellan flickor och pojkar på Mariamottagningarna / Risk factors in young cannabis users with a focus on gender and mental health : A comparison between girls and boys at Mariamottagningarna.

Törnros, Annika, Stålsmeden, Elias January 2017 (has links)
Studiens syfte var att studera risk- och skyddsfaktorer hos ungdomar som använder cannabis med fokus på kön och psykisk ohälsa. Teoretiska perspektiv som användes var Risk- och skyddsfaktorer samt genus. Studien genomfördes genom att analysera data som samlats in via UngDOK inskrivningsformulär på Mariamottagningar i Sverige under åren 2013-2015. Resultatet i vår studie visar att flickor är en utsatt grupp inom de flesta områden med avseende på risk- och skyddsfaktorer och vad gäller psykisk ohälsa så var flickor överrepresenterade inom alla undersökta områden, utom vad det gäller neuropsykiatrisk diagnos där det inte var någon skillnad mellan könen. Slutsatserna vi kan dra av vår studie är således att flickor anger att de upplever sig som mer utsatta än pojkar och att det skiljer mellan flickor och pojkar i graden av riskfaktorer och utsatthet hos dem som svarat på UngDOK inskrivningsformulär. Det är därför relevant att inom socialt arbete och utifrån ett behandlingspedagogiskt perspektiv vara medveten om könstillhörighetens betydelse när det gäller utvecklingen av ett normbrytande beteende, exempelvis substansbruk.
327

Impact de la consommation de cannabis chez les utilisateurs de drogues intraveineuses

Jutras-Aswad, Didier January 2007 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
328

Differential roles of the two major endocannabinoid hydrolyzing enzymes in cannabinoid receptor tolerance and somatic withdrawal

Schlosburg, Joel 21 April 2010 (has links)
While there is currently active debate over possible therapeutic applications of marijuana and cannabis-based compounds, consistently their primary drawbacks have been the psychoactive properties, dependence, and abuse potential. Prolonged administration of ∆9-tetrahydrocannabinol (THC), the primary psychoactive constituent in marijuana, demonstrates both tolerance and physical withdrawal in both preclinical and clinical studies. Repeated THC administration also produces CB1 receptor adaptations in the form of reduced activation of receptors, along with a downregulation of membrane surface receptors, in many brain regions involved in THC-associated behaviors. The increased need for drug to maintain therapeutic effects, and a withdrawal syndrome following discontinuation of use, are common risk factors in drugs of abuse. Recently, compounds have been developed that prolong the availability of the major naturally occurring endogenous cannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), through inhibition of their catabolic breakdown by fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), respectively. The overall objectives of this research are to elucidate the physiologic roles of these two endogenous ligands and to determine if either can produce beneficial therapeutic effects without negative cannabis-like CNS effects. Therefore, we tested the impact of acute and prolonged blockade of FAAH and MAGL on a variety of cannabinoid-mediated behaviors and on precipitated cannabinoid withdrawal. Despite that acute blockade of FAAH and MAGL produce similar efficacy in reducing nociceptive responses, and both can reduce THC-induced somatic withdrawal, sustained blockade of these enzymes leads to remarkably different adaptations in CB1 receptor functioning. Namely, prolonged elevations in brain 2-AG leads to marked antinociceptive tolerance, cross-tolerance to exogenous cannabinoid agonists, and physical dependence. In contrast, sustained elevations in brain anandamide continues to dampen pain responses without apparent signs of physical withdrawal, loss of CB1 receptor activation as measured by [35S]GTPγS, or receptor downregulation as measured by [3H]CP,55940. These results suggest that chronic 2-AG elicits greater compensatory changes in CB1 receptor functions than anandamide. With similar efficacy in most therapeutic endpoints tested, and evidence of reduced impact on long-term function of the endocannabinoid system, these results distinguish FAAH as a more promising therapeutic target to treat pain and other conditions than MAGL.
329

Využití konopí setého ve výuce chemie / Utilization of Cannabis Sativa in Teaching Chemistry

Stránská, Adéla January 2012 (has links)
The diploma thesis deals with Cannabis sativa. The aim is to focus on possible utilization of Cannabis sativa in teaching chemistry. The theoretical part describes the botany of cannabis, overviews phytocannabinoids, substances contained in cannabis, and it also includes wide use of cannabis in agriculture and industry. The practical part deals with the selection and arrangement of a possible curriculum about chromatography as the most affordable technique for analysis of cannabis at school, including the formulation of school experiment methodology using the thin-layer chromatography of Cannabis sativa extract to demonstrate the presence of phytocannabinoids. The practical part also includes the scheme of an educational project on cannabis and describes the latest techniques, as well as the methodology of work with them, which are suitable for analysis of phytocannabinoids.
330

Prevalence a incidence užívání alkoholu, tabáku a konopných drog u kohortů žáků 6., 7. a 8. třídy základní školy / Prevalence and incidence of alcohol tobacco and cannabis use in the cohort of primary school students in 6th, 7th and 8th grade

Jurystová, Lucie January 2012 (has links)
Background The period of adolescence is typical for first experiments and initiation of substance use. The onset of experiments emerges between 11 and 15 years of age according to different authors. Although many adolescents end with experiments, there is still a group of those who proceed to regular use. Frequent, regular and especially heavy substance use represents various risks in many aspects of individual's life. According to various studies earlier onset of substance use may predict serious difficulties in adult stages of life. Important and currently widely discussed question is differences in substance use between boys and girls. Aims To identify the age of cigarette, alcohol and cannabis use onset according to gender. To find out prevalence of use among boys and girls. To find out whether incidence of substance use is higher during school year or summer holidays. Methods The ESPAD questionnaire was used for data collection, which was realized in the period of 34 months from August 2007 until June 2010. Indicators were defined for categories of cigarette smoking, alcohol drinking and experience with cannabis. For clarification of the given hypothesis statistical analyses in Microsoft Office Excel 2007 were used - descriptive statistics, contingency tables, Fisher's F-test and (Student)...

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