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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.
31

Creation of a collegiate level drug testing policy

Stoops, Robbin Lynn 13 October 2010 (has links)
The NCAA, in order to preserve fair and equal competition in intercollegiate athletics, created a drug testing program. In 1987 and again in 1988, student-athletes at two separate universities challenged the NCAA’s drug testing program in a court of law. As a result, constitutional questions pertaining to a student-athlete’s individual rights have surfaced. The purpose of the research was to create a collegiate level drug testing policy to be utilized during the regular season by NCAA Division I member institutions. A drug testing program, based upon individual reasonable suspicion, was created through the analysis of the NCAA’s 1987-988 drug testing rules and drug testing program, legal issues surrounding drug testing, litigation involving the NCAA, and NCAA Division I member institution’s drug testing programs. / Master of Science
32

The Impact of Drug Testing on Secondary School Students

Lee, Elton David 12 1900 (has links)
The purpose of this study determined whether use of student random drug testing provided an effective means to reduce drug usage by secondary school students. The participants included 50,214 7th through 12th grade students in 12 selected public schools. All school districts participated in the Texas School Survey of Substance Use in 1994, 1996, 1998, and 2000. The six districts in the experimental group used drug testing as a method of reducing drug usage among students. The six districts in the control group did not use drug testing. Although athletes and students involved in extracurricular activities remain the focus of random dug testing, this research focused on an entire school population to determine whether drug testing only a select group of students reduced reported drug usage in the entire school. Two questions guided the research: First, does the use of random drug testing have an impact on student drug usage? Second, does the year of implementation of random drug testing have an impact on students' self-reported drug usage? The findings for each research question were categorized according to nine illegal drugs. The researcher used a one-way repeated measures factorial design. The data were analyzed via the univariate (split-plot) 2 x 4 analysis of variance (ANOVA), with the data from four periodic surveys (1994, 1996, 1998, & 2000) as a within-subject factor and the treatment group (participation in drug testing or control/no drug testing) as a between-subjects factor. The results of the study showed there was no statistically significant difference between the experimental group of school districts that used random drug testing and the control group of school districts that did not use random drug testing. In addition, the study showed there was no statistically significant difference in drug usage between the students in districts who began random drug testing in different years (i.e. 1994, 1996, 1998, & 2000).
33

Addressing wastewater epidemiology limitations with the use of dynamic population surrogates, complementary urinalyses and in-situ experiments

Brewer, Alex J. 07 January 2014 (has links)
Wastewater epidemiology is an emerging discipline that requires collaborative research involving analytical chemists, drug epidemiologists, and wastewater engineers. Wastewater epidemiology involves the sampling and quantitative analysis of raw wastewaters from communities for illicit drugs and their metabolites. Mass loads (mass per day) and per capita (mg per day per person) are then calculated from concentrations and indicate the approximate quantity of illicit drugs used and excreted by the community. Limitations to wastewater epidemiology include that the population served by wastewater treatment plants within a day and between days is not well known. In addition, biodegradation of illicit drugs during transit in sewers may affect the concentration and mass flows that reach wastewater treatment plants. This thesis describes a series of studies conducted by an international collaboration between scientists and engineers from the United States and Switzerland to answer these two limitations. The experimental approaches for these studies used included high-frequency wastewater sampling strategies, the use of creatinine as a human urinary biomarker, as well as the use of unique locations as test sites including an open community, a prison in the state of Oregon, and a 5 km section of sewer in Zürich Switzerland. In Chapter 2, the diurnal study on the mass flows of illicit drugs or metabolites was formed over four days in a municipality with a population of approximately 55,000 people. The diurnal trends in illicit substances vary by substance. The high (g/day) mass flows of caffeine, methamphetamine, and creatinine indicate that lower-frequency sampling (approximately one sample per h) may representatively capture the use and excretion of these substances. However, lower and episodic mass flows of cocaine and its primary human metabolite, benzoylecgonine, indicate that higher-frequency is needed to accurately assess the use of the cocaine within the municipality. Normalization of illicit substances to creatinine gave between-day trends in illicit and legal substances that differed from non-normalized trends. Resident use of cocaine and methamphetamine were indicated by normalized mass flows that increased during early morning hours while commuters are largely absent from the community. Chapter 3 describes a series of experiments conducted at an Oregon state prison. The prison setting provided a unique opportunity to study a nearly-fixed population of individuals and their corresponding mass flows of illicit substances, the number of doses per person consumed, as well as an opportunity to quantify the level of agreement between numbers of individuals and the measured mass flows of creatinine. Methamphetamine use was more prevalent than cocaine/benzoylecgonine in the prison over the one month study in which single daily (24 h) composite samples of wastewater were collected. The hypothesis that the mass flows of methamphetamine and cocaine would be lower on days on which random urinalysis testing (RUA) is typically conducted by the prison (Monday-Thursday) was rejected. While the mass flows (mg/d) of methamphetamine were less than those for a nearby open community, the number of estimated doses per person was higher for the prison population. A higher number of positive RUA results were obtained for methamphetamine while none were positive for cocaine, which is consistent with the data obtained from wastewater. The hourly (diurnal) trend in methamphetamine mass loads indicated continual methamphetamine use/excretion inside the prison while cocaine and benzoylecgonine were detected in five hourly composite samples. Use of methamphetamine and cocaine by inmates could not be unambiguously distinguished from that of non-inmates (employees and visitors). The observed diurnal trends in creatinine mass loads were similar to those of an open community and are indicative of the general pattern of human wakefulness/activity. Predicted creatinine mass loads based on the total prison (inmates + non-inmates) were in good agreement with the measured mass loads, which indicates the potential use of creatinine as a quantitative population indicator. Additional research on the biodegradability of creatinine is needed because the prison setting was deliberately selected to minimize the potential for creatinine biodegradation. Chapter 4 addresses the data gap that exists on illicit drug transformation during in situ transit in sewers. The rates of in situ biodegradation have not yet been determined for conditions that are relevant to sewers, which include low to variable oxygen concentrations, the presence of a biofilm, and temperatures ≤ 20 °C. For this reason, two tracer tests were conducted in a 5 km stretch of sewer located near Zürich, Switzerland. The stable-isotope forms (deuterated) of cocaine and benzoylecgonine were injected into flowing wastewater and three locations up to 5 km downstream were sampled over time. Breakthrough curves were constructed from measurements of cocaine-d3 and benzoylecgonine-d3 concentration with time. The area under the curve (mass) was determined by integrating concentration over time. Benzoylecgonine-d3 was present in the injectate that should have only contained cocaine-d3; because the benzoylecgonine-d3 formation prior to injection is not known. The injected mass of cocaine-d3 did not decline over the 5 km distance. The observed mass of cocaine-d3 at 5 km was 10% greater than at 500 m, which indicates that the transformation of cocaine was not significant over the 1.5 h experiment. At 5 km downgradient, the apparent mass of benzoylecgonine-d3 had increased by 35% over that observed at 500 m. However, the apparent increase in benzoylecgonine-d3 mass was not accompanied by a corresponding loss of cocaine-d3. While uncertainty is apparent in the increase of both cocaine-d3 and benzoylecgonine-d3, the ratio of cocaine-d3/benzoylecgonine-d3 is subject only to analytical error because any errors associated with sampling and the integration of masses cancel out. The ratio of cocaine-d3/benzoylecgonine-d3 declined from 2.98 in the injectate to 1.66 at Location 3, which indicated a greater increase in benzoylecgonine-d3 relative to cocaine over the 5 km distance. Due to the benzoylecgonine-d3 that was present in the injectate, any biodegradation of cocaine-c3 to form benzoylecgonine-d3 could not be unambiguously distinguished. During the second tracer test in which benzoylecgonine-d3 was injected, the mass of benzoylecgonine-d3 did not significantly decline, which suggests that the apparent loss of benzoylecgonine-d3 during the cocaine-d3 test cannot be attributed to in-situ biodegradation. Overall, while uncertainty exists about the integrated masses for cocaine-d3 and benzoylecgonine-d3, the 5 km distance was too short in order to observe a significant loss of cocaine-d3 and formation of benzoylecgonine-d3. Recommendations for future research include conducting analysis on the injectate solution to ensure that only cocaine-d3 is introduced so that any formation of benzoylecgonine-d3 is readily apparent and quantifiable. In addition, the tracer tests should be repeated in a longer section of sewer to increase the residence time beyond 1.5 hr and degradation products of benzoylecgonine-d3 should be monitored including ecgonine and ecgonine methyl ester. / Graduation date: 2013 / Access restricted to the OSU Community at author's request from Jan. 7, 2013 - Jan. 7, 2014
34

Examining the effects of drug testing on drug use at the secondary education level

Walter, Sandra M. January 1997 (has links)
The primary purpose of this study was to determine if a drug testing program could impact or change student drug use at the secondary education level. Secondary purposes were to 1) assess the perceptions of secondary education students toward licit and illicit drugs, drug use, and the newly implemented drug testing program, and 2) to examine why drug use may continue even after a drug testing program has been implemented. Data was collected through the use of questionnaires, discussion groups, and one-on-one interviews. Examination of the questionnaire data indicated that student drug use was not substantially deterred by the newly implemented drug testing program over a three to four month time period. Also, students' perceptions of the newly implemented drug testing program were mainly that of disagreement. Students commented that they felt the drug testing policy was implemented to "catch them" using drugs rather than "help them" with a possible drug addiction. One of the main reasons that the drug testing program did not have a great deterrent effect on student drug use, as suggested by the students, was that the odds were not high enough that they would be selected to be drug tested. In some instances, drug testing was not proving to be a deterrent to drug use, but rather a deterrent to participation in school activities. However, for some students, drug testing was proving to be a deterrent to drug use. As quoted from one of the discussion group members: "It's a step in the right direction." / School of Physical Education
35

The emanation of privacy rights in public schools : search and seizure and drug testing

Blyth, Wendy Anne 01 October 2003 (has links)
No description available.
36

Drug absorption enhancement properties of selected South African aloe species.

Lebitsa, Tebogo Abram. January 2013 (has links)
M. Tech. Pharmaceutical Sciences / Following the discovery of an active pharmaceutical ingredient, attempts were made to improve its delivery to the site of action and thereby its effectiveness. Insulin and other therapeutic proteins are administered almost exclusively parenterally because of their poor absorption after oral administration, but this route is associated with disadvantages including pain, discomfort and lipohypertrophy at the site of injection. A suitable absorption enhancer which could effectively improve the absorption of poorly absorbable drugs from the gastrointestinal tract would contribute to the development of an effective oral drug delivery system for these drugs. One such attempt was the formulation of the active ingredient into an appropriate dosage form for a specific route of administration to improve other properties such as manufacturability, stability and bioavailability. Formulation studies led to the development of substances called excipients, which were incorporated into dosage forms, in addition to the active pharmaceutical ingredient, to improve the properties of the final product. Aloe vera gel previously showed the ability to increase the bioavailability of vitamins and to enhance the in vitro transport of a macromolecular drug across intestinal epithelial cell monolayers. However, the effect of leaf materials from aloes, indigenous to South Africa, on drug transport across intestinal epithelia has not previously been investigated. The aim of this study is to evaluate the in vitro drug transport enhancement potential of the gel and whole leaf extract of Aloe ferox, Aloe marlothii, Aloe speciosa and compare them with that of Aloe vera across Caco-2 cell monolayers, as well as across excised rat intestinal tissues.
37

Development and assessment of in vitro tumour models for anti-cancer drug testing

Liu, Xinhui January 2011 (has links)
The study of the development of anti-cancer drugs and preclinical efficacy tests has until today encountered a major problem identified as lack of reliable in vitro tumour models which are able to reflect in vivo tumour conditions. These models provide a clear basis for understanding tumour development processes, assisting in the selection of agents from various chemicals and testing the efficacy of drugs. There are two important characteristics for an in vitro tumour model, i.e. tumour-like structure of cell aggregates, and the in vivo-like culture microenvironment. To meet these two requirements, an in vitro perfusion based three-dimensional tumour model was developed for the three dimensional culture of cancer cells and related anti-cancer drugs tests. In order to assess this model, DLD1 and NCI/ADR cells were cultured in four different models and compared their proliferation rate, cell viability, micro tumour formation and drug responses. In addition, the comparison of static and perfusion culture were done on monolayer and in 3D also. The cells in perfusion culture showed higher proliferation rates and significantly, higher cell viabilities after a 6-day culture compared to statically cultured cells, especially for the cells in the 3D culture. Microtumours (MTs) were formed from this model, which showed significant tumour-like morphological characteristics, a denser and highly stable structure, a higher cell viability, and varied drug responses compared with spheroids. The inhibition effect of paclitaxel and cisplatin, two common type anti-cancer drugs, were tested and a comparative study was carried out using conventional two-dimensional (2D) static culture, spheroids, and the developed 3D MTs model, as well as real human tumour tissues. The results showed that the cells in 2D culture were most greatly inhibited while human tumours showed the lowest drug responses. The efficacy of anti-cancer drugs, tested in conventional 2D static culture, was greatly amplified. Besides, the response of MTs to agents was much closer to that of human tumours, when the values of spheroids are relatively closer to the cells in 2D culture. It is further supported that MTs have more tumour-like characteristics than spheroids. When compared, the inhibition to proliferation of cells in static and perfusion culture showed significantly different drug responses except for the cells on the monolayer. The shown difference between static and perfusion culture can be due to the different culture environment, and further related to the different action mechanisms of anti-cancer agents. The perfusion culture provides a more homogenous and more physiological microenvironment for the in vitro tumour growth, and in vitro perfused 3D cancer model, developed in this thesis, proved valuable for the study of in vitro cancer and related anti-cancer drug tests.
38

A critical examination of the pros and cons of mandatory drug testing in the workplace

Oyarekhua, Justina O. 01 May 1989 (has links)
The primary goal of this degree paper is to critically examine arguments advanced by both the proponents and opponents of mandatory drug testing in the workplace. This study is very significant because it not only addresses a very important issue in the U. S. government and private employer's attempt to solve the drug abuse problem in the workplace, but also helps to highlight the importance of the United States Constitution which protects people from prosecution until they are proven guilty. The U. s. Constitution guarantees the right to "due process" and protects people from illegal search and seizure. Proponents of mandatory drug testing in the workplace argue that the practice helps them to identify and eliminate drug users from the workplace. Above all, mandatory drug testing helps the employer to safe guard and protect the work force which is generally jeopardized by drug users. They assert that no one employee has the right to endanger the lives of other employees. On the other hand, opponents of mandatory drug testing argue that subjecting employees and job applicants to a urinalysis test violates their right to privacy.They claim that the U. s. Constitution protects Americans from illegal search (e.g., urinalysis) and seizure. It is, therefore, not constitutional for employers to keep subjecting their employees to a mandatory drug test. The study revealed that mandatory drug testing has been upheld by various judges in cases where there were "reasonable suspicion" or probable cause to believe that an employee was abusing drugs. Random testing of employees as part of the requirement of an annual examination, as a condition for continued employment and without probable cause, has been declared by most judges as unconstitutional. The study utilized a descriptive approach in its analysis. Information in the study was gathered through interviews, library research (secondary sources) of government documents, reports, books, journals and studies conducted by the National Institute on Drug Abuse and the American Management Association.
39

Adiktologické programy v prostředí zábavy - současný stav, potřeby a bariéry dalšího rozvoje / Drug services in recreational setting - current situation, needs and barriers of further development

Jičinská, Lucie January 2019 (has links)
Despite the fact that the prevalence of drug use in nightlife setngs is signifcantly higher than in the general populaton (EMCDDA, 2015), addictology services in these felds are not a priority in the Czech Republic - nor are they a conceptual and stable aspect of addicton care. The status of these programs is therefore usually fuctuatng and currently not well mapped. The aims of this research were: to describe the current situaton of addictology services within nightlife setngs in the Czech Republic; obtain basic data on the programs that currently operate in this context; describe provided interventons and their scope of reach; and provide an elementary overview of the nature of services and their limits or barriers of the further development. As a method of data collecton, a questonnaire was used among programs operatng in and around entertainment, as well as low-threshold programs in the Czech Republic. The study was conducted using the Computer-Assisted-Web-Interview (CAWI) method. The results show that there are 16 programs currently operatng within nightlife setngs. Most of them are primarily low-threshold harm reducton services for actve drug users. Actvites in this area are offered only sporadically and not prioritzed, which results in limited effectveness and obstacles to further...
40

Análise fenótipo-patogênica da infecção pelo vírus Zika em células humanas neurais in vitro / A phenotypic and pathogenic analysis of Zika virus infection in human neural cells in vitro

Cugola, Fernanda Rodrigues 25 June 2018 (has links)
O Zika vírus (ZIKV) é um flavivírus transmitido pelo mosquito Aedes aegypti e que se espalhou rapidamente pelas Américas, causando uma epidemia no Brasil em 2015 . Um número crescente nos casos de infecções veio acompanhado de um aumento no número de fetos e bebês nascidos com microcefalia, levando a um chamado de emergência mundial de saúde. Históricamente, o ZIKV não havia causado infecções de destaque em humanos e a reermegência dessa ameça viral associada à defeitos do nascimento foi logo relacionada à evolução e consequente distinção entre os genótipos virais, o original Zika africano e seu descendente Zika asiático, que chegou ao Brasil. A hipótese da cepa brasileira do ZIKV ser a causadora de microcefalia e de outros defeitos do nascimento ganhou mais respaldo após a identificação do vírus em amostras de tecido cerebral e líquido amniótico de fetos. Posteriormente, a associação direta entre microcefalia e a síndrome congênita com o ZIKV foi confirmada por meio da aplicação de modelos biológicos experimentais que se revelaram susceptíveis à infecção viral, como células do sistema nervoso central em sistemas 2D e 3D in vitro e camundongos prenhês. Esse trabalho teve como objetivo investigar a infecção da cepa brasileira do ZIKV (ZIKVBR) em diferentes células humanas neurais in vitro diferenciadas a partir de células-tronco pluripotentes induzidas, além de criar uma plataforma para teste de fármacos in vitro contra o vírus. Nossos resultados comprovaram a susceptibilidade e permissividade celular à infecção do ZIKVBR em células neuronais e, em especial, progenitoras neurais, causando morte celular por apoptose. Além disto, quando células progenitoras neurais foram cultivadas em suspensão, formando neuroesferas, o ZIKVBR foi capaz de causar uma redução na população de células, gerando uma anormalidade morfológica semelhante à microcefalia. Além do mais, quando células progenitoras neurais infectadas com ZIKVBR foram diferenciadas em neurônios maduros, a análise da sinaptogênese revelou que esses neurônios apresentavam uma menor densidade de puncta sináptica, indicando um comprometimento no funcionamento das sinapses que pode estar contribuindo para os problemas associados com a síndrome congênita do ZIKV. Por fim, o tratamento dessas células com a droga Sofosbuvir, um inibidor de RNA polimerase dependente de RNA aprovado para uso clínico, foi capaz de resgatar NPCs e neurônios apoptóticos. Em suma, nossos dados indicam que o ZIKVBR infecta preferencialmente células progenitoras neurais, replicando-se eficientemente e causando morte por apoptose nessas células e neurônios maduros diferenciados de células progenitoras neurais infectadas apresentam uma menor desidade de puncta sináptica. Finalmente, a reutilização de compostos farmacêuticos já aprovados para uso clínico pode acelerar o tratamento para indivíduos infectados pelo ZIKV onde a prevenção já não é mais opção, como no caso de mulheres grávidas. / Zika virus (ZIKV) is a mosquito-borne flavivirus transmitted by Aedes aegypti that has rapidly spread through the Americas, causing a widespread epidemic in Brazil in 2015. A increasing number of infection cases was followed by a rise in the number of fetuses and babies born with microcephaly, leading to a global health emergency call. Up to then, ZIKV had not caused meaningful infections in humans and the reemergency of this viral threat associated with birth defects was soon related to viral genotype mutations and its consequent distinction from the original african Zika strain to its descendent asian Zika strain, which reached Brazil. The hypotesis of the brazilian ZIKV strain being responsible for microcephaly and other birth defects gained support after the isolation and identification of the virus in samples of cerebral tissue and amniotic fluid of fetuses. Subsequently, the direct association between microcephaly and congenital syndrome with ZIKV was confirmed through the application of biologic experimental models which proved susceptible to viral infection, as for cells from the central nervous system cultured in 2D and 3D models as well as pregnant mice. The aim of this study was to investigate the brazilian ZIKV strain (ZIKVBR) infection in different human neural cells in vitro differentiated from induced pluripotent stem cells, as well as creating a platform for in vitro drug testing with antiviral capabilities. Our results showed cellular infection susceptibility and permissiveness to ZIKVBR in neurons and, specially, neural progenitor cells, displaying cell death by apoptosis. Futhermore, when neuronal progenitor cells cultured in suspension, forming neurospheres, were infected with ZIKVBR, it caused a reduction in cell population, displayed by evident morphological abnormalities resembling to microcephaly. Additionally, when neural progenitor cells infected with ZIKVBR were diferentiated further into mature neurons, synaptogenesis analysis revealed these neurons displayed fewer synaptic puncta density, indicating a compromise in synapse functioning that may be contributing to problems associated with ZIKV congenital syndrome. Moreover, cell treatment with Sofosbuvir, a RNA polymerase RNAdependent inhibitor approved for clinical use, was able to rescue apoptotic NPCs and neurons. In summary, our results reveal that ZIKVBR preferentially infects neural progenitor cells, efficiently replicating itself and causing death by apoptosis in these cells and mature neurons differentiated from infected neural progenitor cells display reduced synaptic puncta density. Lastly, the repurpose of FDA approved compounds may aid in accelerating treatment for infected individuals whose prevention is no longer an option, as it is for pregnant women.

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