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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.
241

An NMR Study of 2-Ethylbutyllithium/Lithium 2-Ethyl-1-butoxide Mixed Aggregates, Lithium Hydride/Lithium 2-Ethyl-1-butoxide Mixed Aggregates, n-Pentyllithium Aggregates, and n-Pentyllithium/Lithium n-Pentoxide Mixed Aggregates

Sellers, Nicole 12 1900 (has links)
A 13C and 6Li variable temperature NMR study of 2-ethylbutyllithium/lithium 2-ethyl-1-butoxide mixed aggregates formed from reacting 2-ethyl-1-butanol with 2-ethylbutyllithium in two O/Li ratios of 0.2/1 and 0.8/1. The 0.2/1 sample resulted in two 2-ethylbutyllithium/lithium 2-ethyl-1-butoxide mixed aggregates and seven lithium hydride/lithium 2-ethyl-1-butoxide mixed aggregates. The lithium hydride mixed aggregates were also studied using selective 1H decoupling experiments. The 0.8/1 sample resulted in six 2-ethylbutyllithium/lithium 2-ethyl-1-butoxide mixed aggregates and five lithium hydride/lithium 2-ethyl-1-butoxide mixed aggregates. A low temperature 13C NMR spectroscopy study of n-pentyllithium indicated three aggregates, most likely a hexamer, an octamer, and a nonamer. A low temperature 13C NMR study of an 0.2/1 O/Li ratio sample of n-pentyllithium mixed with 1-pentanol resulted in three n-pentyllithium/lithium n-pentoxide aggregates mixed aggregates along with the three n-pentyllithium aggregates. 13C NMR data for this mixture gave inconclusive results whether or not lithium hydride/lithium alkoxide mixed aggregates were present in the sample.
242

Contrasts in Selective Variables between Sociometrically High and Sociometrically Low Third Pupils

Anderson, Ronald W. 01 1900 (has links)
This study was designed to contrast the differences between sociometrically high and sociometrically low individuals, in regard to nine selected variables which were considered to differentiate between these individuals.
243

Desenvolvimento de um sensor potenciometrico para ibuprofeno / Development of a potenciometric sensor for ibuprofen

Ribeiro, Paulo Jose Fernandes 14 July 2006 (has links)
Orientadores: Lauro Tatsuo Kubota, Graciliano de Oliveira Neto / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-08T00:59:06Z (GMT). No. of bitstreams: 1 Ribeiro_PauloJoseFernandes_M.pdf: 3526765 bytes, checksum: d7527897c70e194a6207d1020f2ce8bc (MD5) Previous issue date: 2006 / Resumo: Nesse trabalho é apresentado o desenvolvimento de um eletrodo íon-seletivo para determinação de ibuprofeno, utilizando-se membrana do copolímero poli(etileno co-acetato de vinila) (EVA), tentando minimizar o uso de plastificantes. A membrana foi preparada diretamente sobre um suporte condutor constituído de uma mistura de resina epóxi, endurecedor e grafite. Na preparação da membrana foram estudadas diversas proporções de seus componentes, como concentração de par-iônico, influência do plastificante e quantidades de matriz polimérica. As melhores respostas foram obtidas com uma membrana composta de 115 mg do par-iônico aliquat-ibuprofeno, 170 mg de EVA e 150 mg do plastificante o-NPOE (orto-nitrofeniloctil-éter), não sendo possível eliminar o plastificante. Com o objetivo de otimizar as condições analíticas, foram feitos estudos da influência do pH, da natureza e concentração do tampão e de interferentes, além do tempo de reposta e de vida do eletrodo. As melhores respostas em estado estacionário foram obtidas em tampão Fosfato com concentração de 0,5 mol L a pH 7.0. Nestas condições foi verificado um bom desempenho do eletrodo na faixa de concentração de 2,93 10 a 10mol L, com limite de detecção de 8,7 10 mol L, sensibilidade de 127 mV década, tempo médio de resposta de 56 s e capacidade para aproximadamente 100 determinações. O eletrodo foi aplicado para determinação de ibuprofeno em amostras de medicamento obtendo bons resultados, sendo estes estatisticamente igual aos obtidos com o método de referência a um nível de 95% de confiança. / Abstract: In this work is presented the development of an ion-selective electrode for ibuprofen determination, using the poly(ethylene-co-vinyl-acetate) copolymer (EVA) membrane, trying to minimize the use of plasticizer. The membrane was prepared directly on a conducting support consisting of an epóxi resin, hardener and graphite mixture. In the preparation of the membrane several ratios of its components were investigated, such as concentration of ion-pair, influence of the plasticizer and polymeric matrix. The best performance was reached with a membrane composed with 115 mg of the ibuprofen-aliquat ion-pair, 170 mg of EVA and 150 mg of the o-NPOE (orto-nitrophenyloctyl-ether), being impossible to eliminate the plasticizer. Studies of the influence of pH, nature and concentration of the buffer and the interfering were carried out looking for the optimized conditions for the electrode performance like sensitivity, fast response and lifetime. The best response was obtained with Phosphate buffer in a concentration of 0,5 mol L at pH 7.0. In these conditions the electrode showed a good performance in the concentration range between 2,93 10 and 10 mol L, with a sensitivity of 127 mV/decade, a detection limit of 8,7 10 mol L, response time of 56 s and capacity for 100 determinations. The electrode was employed to determine ibuprofen in medicine samples obtaining good results, being statistically equal at 95% confidence level, when compared with the results obtained with the reference method for the same samples. / Mestrado / Quimica Analitica / Mestre em Química
244

Exploring the impact of power on information consumption decisions

Stuart, Jillian O'Rourke 01 August 2016 (has links)
In general, people prefer information that makes them look and feel good. This is information that is consistent with, or supportive of, their desires, beliefs, and behaviors. Much research has been devoted to examining biases in how we selectively seek some information and avoid other information as well as different factors that can mitigate or intensify these tendencies. The present project explored the impact of feeling powerful—a psychological experience shown to influence cognitions and behavior—on decisions about what information people choose to consume in a health context. Specifically, this was investigated in two different domains of health information consumption—selective exposure (Studies 1 & 2) and information avoidance (Studies 3 & 4). The first two studies investigated if feeling powerful affects selection of, or interest in, information known to be consistent or inconsistent with beliefs and behaviors. It was predicted that power would increase interest in belief-consistent (i.e., non-threatening) information. The final two studies examined how power impacts decisions about whether to receive or avoid an uncertain piece of health information that is potentially threatening. Contrary to selective exposure hypotheses, it was predicted that power would increase interest in this uncertain (i.e., threatening) information. All four studies revealed null largely effects of power, suggesting that feeling powerful may not influence how people chose to consume potentially threatening health information. A discussion of the potential limitations of these studies and the scope of this conclusion are included.
245

Under the Influence of Marc Blitzstein: Examining Leonard J Lehrman’s Uses of Serial Techniques for Dramatic Purposes in Karla

Blackwood, Jeremy B 12 1900 (has links)
American composer, author and conductor Leonard J. Lehrman (b. 1949) has spent a majority of his lifetime devoted to the scholarship on the music of Marc Blitzstein (1905-1964). Lehrman completed Blitzstein’s Idiots First in 1973, and finished his own one-act opera Karla in 1974. In an effort to honor Blitzstein, Lehrman included Karla along with Idiots First to begin the set of one-act operas to be titled Tales of Malamud. Lehrman coined the term “selective serialism” in reference to Blitzstein’s use of serial techniques representing something associated with death or something diabolical. Lehrman applies a similar technique in that he uses serialism to reference the presence of a handwritten notes that are tied to the dramatic context of the opera. This study examines Lehrman's use of serialism in Karla as it was directly influenced by Blitzstein’s use of serialism in Idiots First.
246

Targeting Interleukin-4 Receptor α with Hybrid Peptide for Effective Cancer Therapy. / ハイブリッドペプチドを用いたInterleukin-4 Receptor αを標的とした効果的な抗癌療法

Yang, Liying 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18157号 / 医博第3877号 / 新制||医||1003(附属図書館) / 31015 / 京都大学大学院医学研究科医学専攻 / (主査)教授 武藤 学, 教授 清水 章, 教授 生田 宏一 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
247

Effects of Perceptual Load on Dichotic and Diotic Listening Performance

Lynch, Erin E. 10 September 2021 (has links)
No description available.
248

Assessing Motivational and Associative Learning Mechanisms Underlying Compulsive Drinking

Carron, Claire R. 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Continued consumption of alcohol despite the knowledge of negative consequences is a hallmark of alcohol use disorder (AUD), yet much remains unknown about what motivates these behaviors. Compulsive drinking may require motivational resources that are not necessary when drinking in unchallenged conditions in order to counteract the addition of these negative consequences. Increased sensitivity to drug-paired stimuli via associative learning processes may provide this additional motivation. To evaluate if alcohol-paired stimuli enhance alcohol seeking, selectively bred crossed High Alcohol Preferring mice experienced Pavlovian conditioning procedures with an alcohol unconditioned stimulus. We hypothesized that after repeated pairings, alcohol cues would elicit seeking conditioned responses. Then, to determine if the motivation provided by these cues influenced responding, mice were trained to respond for alcohol and tested in the presence of alcohol cues. Finally, to test if alcohol-paired cues influence compulsive drinking, this same test was repeated with the addition of response-contingent footshock. We hypothesized the cue paired with alcohol would increase responding for alcohol in unchallenged conditions, but especially in challenged conditions, contributing to compulsivity. An auditory stimulus paired with alcohol did elicit enhanced seeking responses, but contrary to hypothesis, we observed no effect of these same cues on instrumental responding. To validate these findings, training and testing procedures must be optimized to ensure conditioning has properly occurred and compulsivity is being appropriately measured.
249

Effects of Background Noise on the Speech Acoustics of People With Aphasia

Dixon, Kirsten 06 August 2021 (has links)
This study investigated the effect of hearing six background noise conditions (silent baseline, pink noise, monologue, lively conversation, one-sided phone call, and cocktail noise) on acoustic measures of speech production during story retells in people with aphasia. Eleven individuals with aphasia and 11 age- and gender-matched control participants took part in the study. Participants heard the background noise conditions through open-back headphones while they retold six short stories. The examiner calculated mean and standard deviation of intensity, mean and standard deviation of fundamental frequency (F0), and speech rate in words per minute. A Matlab application that identified pauses (i.e., periods of silence greater than 200 ms) computed a speaking time ratio measure (i.e., time speaking versus time pausing). With the exception of the monologue and one-sided phone call condition, both people with aphasia and control participants significantly increase their intensity and F0 in the presence of background noise. Additionally, participants with aphasia have significantly lower speaking time ratios and speaking rates when compared to control participants. Participants make acoustic changes while hearing background noise; speech intensity rises in an effort to increase the signal-to-noise ratio, while mean F0 increases due to a presumed rise in subglottal pressure. Further research is suggested to investigate other acoustic differences, possibly at the segmental level, between speech produced in informational and energetic background noise.
250

Evolutionary Dynamics of Influenza Type B in the Presence of Vaccination: An Ecological Study

Fiedler, Lindsey J. 24 June 2019 (has links)
Understanding the evolutionary dynamics of influenza type B in human hosts is a public health concern as we strive to minimize the disease burden in seasonal epidemics. Vaccination is considered the best defense against contracting influenza, and everyone over the age of 6 months is advised to get vaccinated before each season. The effect that vaccine-acquired immunity has on the evolution of influenza B remains unclear. In the U.S., vaccine-uptake is irregular across the states, and the differing coverages present an opportunity to study how vaccination influences viral evolution. This thesis analyzes the evolutionary patterns of influenza B in the presence of vaccine-induced selective pressure. Using an ecological study design, estimates on statewide vaccination coverages from the Centers for Disease Control and Prevention were related to influenza B sequence data. The phylogenies and the frequencies of single nucleotide polymorphisms for high and low coverage states across three influenza seasons were compared to evaluate if there was evidence of vaccination influencing evolution. Overall, the results show that vaccination does not significantly impact the evolutionary dynamics of influenza B with both high and low coverage states showing interspersed phylogenetic trees and similar antigenic diversities.

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