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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.
41

Do delay signals modulate the effect of d-amphetamine on "self-control" choice?

Higgins, William J. January 2009 (has links) (PDF)
Thesis (M.A.)--University of North Carolina Wilmington, 2009. / Title from PDF title page (January 12, 2010) Includes bibliographical references (p. 62-67)
42

Desenvolvimento de metodologia analítica para a investigação de anfetaminas em amostras de saliva, empregando cromatografia em fase gasosa acoplada a espectrometria de massas / Development of analytical methodology for the investigation of amphetamines and derivatives in oral fluid samples using gas chromatography coupled with mass spectrometry

Rafael Barcellos Bazzarella 30 March 2010 (has links)
O uso de drogas estimulantes por motoristas é reconhecidamente responsável por um aumento significativo na quantidade de acidentes nas estradas e rodovias. A própria exigência do trabalho muitas vezes acaba direcionando-os para a busca de algo que lhes proporcione maior estado de vigília e atenção nas estradas. Com base na importante correlação entre a profissão e o uso de substâncias anfetamínicas, foi proposta uma metodologia analítica para a determinação de anfetamina, metanfetamina, 3,4 metilenodioxianfetamina, 3,4 metilenodioximetanfetamina e 3,4 metilenodioxietilanfetamina em amostras de saliva através de técnica de extração líquido-líquido e análise por cromatografia em fase gasosa acoplada a espectrometria de massas (GC-MS). Para o desenvolvimento do método foi utilizado 1 mL de saliva, extração líquido-líquido com o solvente acetato de etila, derivatização com anidrido heptafluorobutírico (HFBA) e detecção com GC-MS. A metodologia foi validada e demonstrou linearidade de 10 a 400 ng/mL de saliva para todos os compostos. Os limites de detecção estabelecidos se encontraram entre 2,5 ng/mL e 7,5 ng/mL, enquanto os de quantificação foram de 10 ng/mL para todos os compostos. A exatidão apresentou valores entre 93,8% e 108,3%, a precisão intra-ensaio valores entre 4,05% e 9,34% e a precisão inter-ensaio valores entre 5,28% e 9,90%. A metodologia validada foi aplicada em amostras de saliva de caminhoneiros que trafegavam na região da cidade de Roseira SP em um evento de atendimento ao público promovido pela Sest/Senat (Serviço Social do Transporte/ Serviço Nacional de Aprendizagem do Transporte) em parceria com a Polícia Rodoviária Federal. Duas amostras de saliva de um total de 40 amostras analisadas apresentaram resultado positivo para anfetamina. / The use of stimulants by professional drivers is known as an increasing risk of accidents on the roads. The type of work itself induces the drivers to look out for something that provides better state of alertness and reduced sleep. Based on this important correlation between the occupation and use of stimulants, an analytical methodology was proposed for the determination of amphetamine, methamphetamine, and their methylenedioxy derivatives 3,4 methylenedioxyamphetamine, 3-4 methylenedioxymethamphetamine and 3,4 methylenedioxyethylamphetamine on oral fluid samples using solvent extraction and gas chromatography coupled with mass spectrum for detection and quantification of these analytes. The developed methodology used 1 mL of oral fluid, liquid-liquid extraction, heptafluorobutyric anhydride and gas chromatography-mass spectrometry for the detection and quantification. The methodology was validated and showed good linearity within the limits of 10 ng/mL and 400 ng/mL of oral fluid. The limits of detection were between 2.5 ng/mL and 7.5 ng/mL, while the limits of quantification were 10 ng/mL for all analytes. The accuracy showed values between 93.8% e 108.3%, the intra-assay precision between 4.05% e 9.34% and the inter-assay precision between 5.28% e 9.90%. The validated methodology was tested in oral fluid samples collected from truck drivers near the city of Roseira São Paulo during an event of health assistance fomented by SEST/SENAT in partnership with Federal Police. It was collected 40 saliva samples and two of them presented positive result for amphetamine.
43

Rapid Inline Derivatization of Primary and Secondary Amine Containing Drugs by Capillary Electrophoresis with Laser-Induced Fluorescence

Turnquest, Britt E. 14 November 2013 (has links)
Despite the ongoing “war on drugs” the seizure rates for phenethylamines and their analogues have been steadily increasing over the years. The illicit manufacture of these compounds has become big business all over the world making it all the more attractive to the inexperienced “cook”. However, as a result, the samples produced are more susceptible to contamination with reactionary byproducts and leftover reagents. These impurities are useful in the analysis of seized drugs as their identities can help to determine the synthetic pathway used to make these drugs and thus, the provenance of these analytes. In the present work two fluorescent dyes, 4-fluoro-7-nitrobenzofurazan and 5-(4,6-dichlorotriazinyl)aminofluorescein, were used to label several phenethylamine analogues for electrophoretic separation with laser-induced fluorescence detection. The large scale to which law enforcement is encountering these compounds has the potential to create a tremendous backlog. In order to combat this, a rapid, sensitive method capable of full automation is required. Through the utilization of the inline derivatization method developed whereby analytes are labeled within the capillary efficiently in a minimum span of time, this can be achieved. The derivatization and separation parameters were optimized on the basis of a variety of experimentally determined factors in order to give highly resolved peaks in the fluorescence spectrum with limits of detection in the low µg/mL range.
44

Tolerance to the Behavioral Effects of Methylphenidate

Brewin, Anne M. 05 1900 (has links)
Thirty-one rats were trained on a differential reinforcement of low rate schedule. After responding had stabilized, animals were injected with methylphenidate, twice weekly, presession. Methylphenidate produced dose-dependent increases in response rates and decreases in reinforcements. Repetition of these doses produced a reduced drug effect, and a third administration of the 10 mg/kg dose further reduced the drug effect. Subsequently, the effects of daily and intermittent administration were determined for this dose. Daily methylphenidate, pre-session, produced tolerance to the behavioral effects of methylphenidate and cross-tolerance to the amphetamines. Twice-weekly methylphenidate, pre-session, produced partial tolerance to methylphenidate and partial cross-tolerance to the amphetamines. Thus, periodic exposure to the behaviorally disruptive effects of a drug of the amphetamine class reduces the effects of subsequent exposure.
45

Effects of morphine on intracranial self-stimulation : the involvement of associative factors and the role of ventral tegmental dopamine neurons

Hand, Timothy Henry. January 1985 (has links)
No description available.
46

Relationships among amphetamine-induced locomotor activity, stereotypy, memory facilitation and conditioned taste aversion

Carr, Geoffrey David. January 1981 (has links)
No description available.
47

Analysis of Demographic Influences on Drug and Alcohol Use In Individuals That Screen Positive For Suicide Risk in the Emergency Department

Orr, Victoria L 01 January 2022 (has links)
Suicide is a growing public health problem, and the 12th leading cause of death overall in the United States. Past research has been conducted on individuals who screen positive for suicide to determine risk factors and suicide patterns across age groups. However, limited little research has been conducted on individuals that screen positive for suicide risk in an emergency department setting. Through the use of a longitudinal, secondary dataset from the Florida Implementation of the National Strategy for Suicide Prevention Project, the relationship between alcohol and drug use and generation (Baby Boomers, Generation X, and Millennials), age, and living status was analyzed in adults (25+) who screened positive for suicide risk in the emergency department. Omnibus chi-square statistics and adjusted standardized residual analyses were used to assess differences in alcohol and drug use amongst generations, age groups, and living statuses. Results indicated significant differences between alcohol, opioid, and amphetamine use and frequency among individuals living with family and in unsheltered environments and marijuana use in Generation X and Millennials. Limitations include sample size and self-reported measures of frequency and usage of drugs and alcohol, which warrant future studies to expand upon these findings.
48

Chemical Ionization (CI) GC/MS Analysis of Underivatized Amphetamines Followed by Chiral Derivatization to Identify d and l-Isomers with Ion Trap Mass Spectrometry

Tarver, John A. (John Arthur) 05 1900 (has links)
An efficient two step procedure has been developed using CI GC/MS for analyzing amphetamines and related compounds. The first step allows the analysis of underivatized amphetamines with the necessary sensitivity and specificity to give spectral identification, including differentiation between methamphetamine and phentermine. The second step involves preparing a chiral derivative of the extract to identify d and 1-isomeric composition.
49

Common chemicals as precursors of improvised explosive devices : the challenges of controlling domestic terrorism

Rostberg, James I. 09 1900 (has links)
CHDS State/Local / During the past decade the world has witnessed an increase in the use of Improvised Explosive Devices (IEDs). Explosives in the hands of terrorists continue to pose a significant threat. Lessons learned indicate that when traditional explosives become difficult to obtain, bomb makers turn to common chemicals as precursors to manufacture explosives. Only the imagination and the availability of certain chemicals limits the number explosives which can be manufactured with relative ease utilizing common chemicals readily available in our communities. Availability of precursor chemicals and ease by which explosives can be manufactured, increase the potential that IEDs will be deployed in the Homeland and requires a careful study of the options necessary to defeat IED deployment. This thesis analyzes various options, policies and procedures to ascertain which would be most appropriate to defeat explosives manufactured from common chemicals. Options include removing, restricting, and tracking certain chemicals available to the public as well as increasing awareness to emergency responders and the public. State and federal legislation pertaining to methamphetamine laboratories is analyzed to identify potential crossover legislation to counter explosives manufacture. Intelligence gathering and information sharing technologies and procedures are assessed for effectiveness as law enforcement tools. / Director, Isanti County Office of Homeland Security and Emergency Management
50

Análise toxicológica de anfetaminas e benzodiazepínicos em amostras de cabelo por cromatografia gasosa acoplada à espectrometria de massas / Toxicological analysis of amphetamines and benzodiazepines in hair samples by gas chromatography coupled to mass spectrometry

Pantaleão, Lorena do Nascimento 22 January 2013 (has links)
As anfetaminas compreendem uma série de compostos com estrutura química semelhante à feniletilamina e que apresentam atividade estimulante do sistema nervoso central. Além de substâncias anorexígenas como o femproporex e a dietilpropiona, também estão incluídas nessa classe drogas ilícitas como a metanfetamina (ice, speed) e a metilenodioximetanfetamina (MDMA, ecstasy). Essas substâncias apresentam grande potencial de abuso, podendo ser utilizadas por diversos grupos sociais como motoristas profissionais (onde são conhecidas por \"rebite\"), estudantes, jovens (utilizando ecstasy em festas denominadas \"raves\") e pessoas que abusam de moderadores de apetite para o controle de peso. Interessantemente, há também a possibilidade de alguns indivíduos utilizarem anfetaminas em associação com benzodiazepínicos. Embora a comercialização dos derivados anfetamínicos tenha sido proibida no Brasil desde 2011, é de conhecimento que algumas pessoas ainda utilizam anorexígenos e recorram ao uso concomitante com benzodiazepínicos como forma de controlar a insônia provocada pelas anfetaminas. Outra situação de uso das duas substâncias ao mesmo tempo seria a de motoristas profissionais, usuários de \"rebite\", que também tentariam controlar os ciclos de sono utilizando benzodiazepínicos. Em vista dessa situação, seria interessante o monitoramento do uso desses grupos de fármacos através de análises toxicológicas. As análises toxicológicas convencionais (realizadas sobremaneira em sangue e urina) geralmente fornecem uma pequena janela de detecção, o que faz com que o uso intermitente possa não ser detectado. Quando se deseja informação de uso em longo prazo ou ainda sobre os padrões de uso de determinada droga, a matriz mais eficiente para realização das análises é o cabelo. No presente projeto, métodos analíticos foram desenvolvidos visando a detecção de fármacos da classe das anfetaminas (anfetamina, metanfetamina, MDMA, MDA e femproporex) e benzodiazepínicos (diazepam, nordiazepam, clordiazepóxido, oxazepam, clonazepam e temazepam) em amostras de cabelo. A microextração em fase líquida (LPME) e a extração em fase sólida (SPE) foram utilizadas como técnicas de preparação de amostras. Os analitos de interesse foram identificados por cromatografia em fase gasosa acoplada à espectrometria de massas (GC-MS). Após o desenvolvimento, otimização e validação, os métodos foram aplicados em amostras reais de voluntários suspeitos de utilizar alguma das substâncias em estudo, provenientes de um centro para tratamento de dependência química. Os resultados obtidos com a aplicação dos métodos mostraram sua eficácia para o fim que se destinam. / Amphetamines are a class of compounds with chemical structures similar to phenylethylamines that present stimulant activity in the central nervous system. Anorectic drugs such as fenproporex and diethylpropion and some illicit drugs as methamphetamine (ice, speed) and metilenodioximetamphetamine (MDMA, ecstasy) are also included in this class. These substances have a high abuse potential, and they can be used by various social groups, for example, professional drivers (who call them \"rebites\"), young students (using ecstasy in \"rave\" parties) and people who abuses anorectics to weight control. Interestingly, there is also a possibility of some people using anorectics and benzodiazepines in association. Although the commercialization of amphetamine derivatives has been recently banned in Brazil (2011), it is known that some people still use anorectic drugs and benzodiazepines to control insomnia induced by amphetamines. Another case of concomitant use would be professional drivers, who use \"rebites\", which also try to control their sleep cycles using benzodiazepines. Because of this situation, it would be interesting to monitoring the use of these drugs by toxicological analysis. The conventional toxicological analyses (performed in most cases in blood and urine) generally provide small window detection. In this case, intermittent drug use may not be detected. When long term information about drug use is needed, the most efficient matrix to carry out the analysis is hair. In this project, analytical methods were developed for the determination of amphetamines (amphetamine, methamphetamine, MDMA, MDA and fenproporex) and benzodiazepines (diazepam, nordiazepam, chlordiazepoxide, oxazepam, clonazepam and temazepam) in hair samples. Liquid-phase microextraction (LPME) and solid phase extraction (SPE) were used as sample preparation techniques in these methods. Analites were identified by gas chromatography/mass spectrometry (GC-MS). After the development, optimization and validation, the methods were applied in hair samples collected from patients of a drug rehabilitation clinic. The results obtained with the application of the developed methods showed their efficacy for the intended purpose.

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