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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.
131

Pavlovian conditioning of LPS-induced TNF-a regulation, sickness behavior and taste aversion in mice

Washio, Yukiko. January 2008 (has links)
Thesis (Ph. D.)--University of Nevada, Reno, 2008. / "December 2008." Includes bibliographical references (leaves 39-44). Online version available on the World Wide Web.
132

Selective lesion of cholinergic neurons of the septal hippocampal tract memory and learning /

Fitz, Nicholas Francis. January 2009 (has links)
Thesis (Ph.D.)--Duquesne University, 2009. / Title from document title page. Abstract included in electronic submission form. Includes bibliographical references (p. 123-151) and index.
133

Desenvolvimento de filmes nanoestruturados Layer-by-Layer com foco em sistemas de materiais sensíveis a estímulos. /

Campos, Paula Pereira January 2018 (has links)
Orientador: Marystela Ferreira / Resumo: Neste trabalho foram desenvolvidos diferentes tipos de filmes Layer-by-Layer (LbL) sensíveis a variação de pH, temperatura, exposição a luz e presença de carboidratos, com o objetivo de criar sistemas com resposta a estímulos que podem ser aplicados na área médica e ambiental para a entrega modificada de fármacos e pesticidas. O trabalho foi dividido em três partes, sendo o primeiro focado na liberação da emodina. Foram fabricados filmes com a emodina imobilizada diretamente e outra em que o fármaco foi encapsulado nos lipossomos formados por dipalmitoil fosfatidil glicerol (DPPG) e palmitoil fosfatidil glicerol (POPG) e então intercalado com polieletrólitos. Ambos os filmes foram expostos a condições fisiológicas e liberaram a emodina por um período prolongado em função da mudança de pH e temperatura. A segunda parte do trabalho é focado na construção de filmes com um polímero baseado em espiropirano (poli(SP-R)), um composto que quando recebe luz UV é convertido para a forma aniônica merocianina (poli(MC-R)) mudando sua cor e carga superficial. O filme foi composto pelo policátion poli(alilamina hidroclorada) (PAH) formando o (PAH/poli(SP-R))n que se desprendeu do substrato pelo processo disassembly após longo tempo de exposição à luz branca. Na terceita parte do trabalho foram desenvolvidos filmes com o polímero baseado em ácido fenil borônico (PBA), que tem a capacidade de se ligar covalentemente à açucares. Foram fabricados intercalado com PVS resultando no filme (PEI/PV... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work, we developed some types of Layer-by-Layer (LbL) films sensible to pH and temperature changes, light exposition and carbohydrates solutions, with the aim of to create stimuli responsive system that can be applied to medical and environmental area to drug and pesticide modulated delivery. The work was divided in three parts, the first one is based on delivery emodin. One film was fabricated with emodin immobilized directly and other the drug was encapsulated on liposomes formed by dipalmitoyl phosphatidyl glycerol (DPPG) e palmitoyl phosphatidyl glycerol (POPG) and the carrier was intercalated with polyelectrolytes. Both systems were exposed to physiologic conditions and released the emodin for prolonged time in function of pH and temperature changes. On second part of this work it was focused on construction of film with spyropiran (SP) based polymer (poli(SP-R)). The UV irradiation over (poli(SP-R)) causes the conversion to anionic and purple merocyanine molecule (poli(MC-R)) changing the color and surface charge. The film were composed by poly(allylamine hydrochloride) (PAH) and poly(SP-R) forming the (PAH/poli(SP-R))n LbL film which disassemble after long time exposed to white light. On third part of work, films were developed with phenyl borônico acid (PBA) based polymer that has the capacity to bind covalently on sugars. The films were intercalated with PVS creating the coating (PEI/PVS)2(PBAp/PVS)n. It were prepared also a film with the pyranine (PYR), the ... (Complete abstract click electronic access below) / Doutor
134

THE EFFECTS OF AUDITORY STIMULI ON THE RATING OF OUTCOMES OF A SLOT MACHINE

Smith, Jamie Melissa 01 May 2014 (has links)
The near-miss effect has been demonstrated to maintain gambling behavior by producing physiological changes or thoughts that an individual has "almost won" or was "close" to a winning outcome when, in fact, they lost. Participants were asked to rate each outcome presented on a 10-point Likert scale regarding how close they perceived an outcome was to a win on an automated slot machine created on a Visual Basic program. Data was analyzed for differences between similar outcomes presented with and without an auditory stimulus. Near-miss outcomes presented with an auditory stimulus were rated significantly higher than near-miss outcomes without an auditory stimulus on average across participants. Implications may reveal the effects auditory stimuli on modernized slot machines have on gambling behavior and options for treatment.
135

Attentional Window and Global/Local Processing

Schultz, Steven Peter 16 June 2016 (has links)
How does the focus of attention influence the encoding of information? Research has shown that size and allocation of the attentional window has an influence on what information is attended to or missed. The size-scale of features also effects processing of visual information. Previous research involving hierarchical stimuli suggests precedence for global features. In the present experiment, I investigated the influence of attentional window size on accuracy of encoding hierarchical stimuli at the global and local level. Here I introduce a new method for manipulating the size of the attentional window and for collecting unconstrained responses. At the start of each trial, observers tracked a dashed-line rectangular box, which either broadened or narrowed in size after onset. This sequence was immediately followed by a brief presentation of two hierarchical letters presented simultaneously on the left and right sides of the screen. The box preceding the hierarchical letters either broadened to a size large enough to include both letters at the global level, or narrowed to a size small enough to include a maximum of two letters at the local level at either side of the screen. Observers reported all letters they were able to identify. Results from two experiments indicate an overall precedence of global letters. However, a narrow attentional window reduced global precedence, as would be expected with more focused attention. The narrow windows also produced more same-side identifications of both global and local letters. The second experiment also showed that reducing the processing time decreased the global advantage.
136

Synthesis of Stimuli-responsive Hydrogels from Glycerol

Salehpour, Somaieh January 2012 (has links)
Due to an increased environmental awareness and thus, concerns over the use of fossil-based monomer for polymer production, there is an ongoing effort to find alternatives to non-renewable traditional monomers. This has ushered in the rapid growth in the development of bio-based materials such as green monomers and biodegradable polymers from vegetable and animal resources. Glycerol, as a renewable bio-based monomer, is an interesting candidate for sustainable polymer production. Glycerol is a renewable material that is a by-product of the transesterification of vegetable oils to biodiesel. Utilization of the excess glycerol derived from the growing biodiesel industry is important to oleochemical industries. The main objective of this thesis was to produce high molecular weight polyglycerol from glycerol and synthesize stimuli-responsive polyglycerol hydrogels. The work began with an investigation of the step-growth polymerization of glycerol to relatively high molecular weight polyglycerol using several catalysts. The catalytic reaction mechanisms were compared and the polymer products were fully analyzed. High molecular weight partially branched polyglycerol with multimodal molecular weight distributions was obtained. The polymerization of glycerol proceeded fastest with sulphuric acid as catalyst as indicated by the highest observed conversion of monomer along with the highest molecular weights. Theoretical models were used to predict the gel point and to calculate monomer functionality. High molecular weight polyglycerol was used to synthesize novel stimuli-responsive hydrogels. Real-time monitoring of step-growth polymerization of glycerol was investigated using in-line and off-line Attenuated Total Reflectance/Fourier Transform infrared (ATR-FTIR) technique.
137

Brushes of self-assembled nanotubes for temperature-responsive biocatalysis / Brosses de nanotubes autoassemblés pour la biocatalyse contrôlée par la température

Ramirez Wong, Diana Guadalupe 09 September 2014 (has links)
Nous nous sommes inspirés des solutions élégantes que la Nature propose, concernant le contrôle et l’optimisation de réactions spécifiques, pour présenter une tentative d’imitation des interfaces biocatalytiques au niveau de nanotubes. Des brosses de nanotubes auto-assemblés à l’aide d’un composé enzymatique, la bêta-lactamase, ont été préparées via des techniques de nanofabrication comme le «layer-by-layer» et le «hard templating».En premier lieu, les effets de confinement géométriques et ses conséquences ont été étudiés et comparés pour des assemblages de films de chitosan/bêta-lactamase sur des surfaces planes et au sein de membranes nanoporeuses.Ensuite, des nanotubes de polyélectrolytes de dimensions contrôlées ont été préparés dans des membranes nanoporeuses puis ancrés sur une surface par couplage chimique pour obtenir des brosses de nanotubes. Des études cinétiques révèlent la présence d’enzymes actives dans ces brosses et une amélioration de la préservation de l’activité quand la bêta-lactamase a été déposée dans les couches intérieures des nanotubes.Enfin, une variété de couches thermo-sensibles avec différentes architectures a été testée pour contrôler la diffusion du substrat sur les films multicouches de bêta-lactamase. L’intégration d’éléments thermo-sensibles stables a été prouvée. Mais des expériences complémentaires avec des mécanismes plus complexes tels que le couplage des réponses thermiques et mécaniques sont nécessaires pour contrôler la biocatalyse impliquant des couches supplémentaires.En résumé, cette étude présente des éléments ouvrant la voie à l’intégration de techniques pour la fabrication de nanostructures complexes pour la biocatalyse. / Inspired by the elegant solutions that Nature has provided to control and promote specific site-reactions, my work presents an attempt to mimic filamentous biocatalytic interfaces. Brushes of self-assembled nanotubes with an enzymatic component (beta-lactamase) were prepared taking advantage of preexisting nanofabrication techniques, such as layer-by-layer and hard-templating.First, the effects of geometrical confinement and its consequences were investigated by comparison of (chitosan/beta-lactamase) multilayer film assembly on flat surfaces and in nanoporous membranes. In a second stage, polyelectrolyte nanotubes with controlled dimensions were prepared in nanoporous membranes and further anchored on a surface by chemical crosslinking to obtain brushes of nanotubes. The kinetic studies revealed the presence of active enzyme in the brushes and enhanced activity preservation when beta-lactamase was deposited as the inner layers of the nanotubes.As a final step, a variety of thermo-responsive coatings with different architectures were tested to control substrate diffusion on top of beta-lactamase-based multilayer films. The integration of stable thermo-responsive elements was proven, although further experiments are required to control biocatalysis with additional layers and using more complex mechanisms, such as coupled thermal and mechanical responses. Knowing that there are more challenges to face before reaching optimum nanotube brushes and apply them for controlled biocatalysis, this study contributes with some elements that may pave the way towards the integration of different techniques for the fabrication of complex biocatalytic nanostructures.
138

The Evocative and Repertoire-Altering Effects of Contingency-Specifying Stimuli

Mistr, Kathryn N. (Kathryn Noel) 08 1900 (has links)
The effects of deadlines in contingency-specifying stimuli among nine 4 to 5 year old children were investigated. Each child was given verbal statements differing in the specified deadline, the delivery of the reinforcer, and the opportunity to respond. The results indicated: (a) statements not specifying deadlines or reinforcers failed to control the children's behavior reliably, (b) specifying deadlines, either immediate or delayed, and immediate reinforcers exerted reliable control over the children's behavior when the opportunity to respond was immediately available, and (c) specifying delayed deadlines or no deadlines and immediate or delayed reinforcers did not reliably control the children's behavior when the opportunity to respond was delayed.
139

Uma abordagem metodológica para quantificar os efeitos cognitivos na análise sensorial de alimentos / A methodological approach to quantify the cognitive effects in sensorial analysis of food

Ellen Cristina Moronte Tech 23 January 2013 (has links)
A preocupação crescente com o desenvolvimento de hábitos saudáveis e uma alimentação adequada vêm promovendo o avanço nas ciências dos alimentos, como também nas relações entre estes e o homem. Nas últimas décadas, a qualidade da análise sensorial tem sido estudada não apenas com base na interação entre o homem e o alimento, mas através da compreensão dos fatores subjetivos e emocionais que influenciam os consumidores. O interesse pelos aspectos emocionais que influenciam essas escolhas amplia os estudos para o terreno das ciências psicológicas, que procuram entender as bases neurocognitivas e analíticas do funcionamento cerebral como motivadores desses processos no homem. O trabalho em neurociência cognitiva tem vislumbrado novos paradigmas, com o desenvolvimento de novas técnicas de observação do cérebro, visando conhecer sua estrutura e função, além de permitir a associação de um comportamento clinico ou experimentalmente observado, não só a um correlato mental presumido, mas também a marcadores específicos da atividade mental observada. Neste sentido, a atividade elétrica cerebral adquirida usando-se o eletroencefalograma (EEG) vem sendo, recentemente, muito usada para monitoramento de eventos cerebrais. Portanto, este trabalho tem como objetivo propor um modelo de análise sensorial que permita avaliar quantitativamente a ação do estímulo gustativo no contexto cognitivo, utilizando o EEG. O experimento foi realizado no laboratório de Física Aplica e Computacional (LAFAC), na Universidade Estadual de São Paulo (USP), Campus Pirassununga, no período de maio/2011 a maio/2012, com 23 voluntários (13 do sexo feminino e 10 do sexo masculino), com idade entre 19 e 24 anos. Foram coletados os sinais de EEG destes voluntários no momento em que experimentavam 27 amostras do sabor doce, sendo nove delas a 0% (água), nove com 0,15% de sacarose (limiar) e nove com 5,0% (concentração máxima). Desta amostragem, foi selecionado um grupo de 7 voluntários (5 do sexo feminino e 2 do sexo masculino) para análise dos dados. Neste estudo constatou-se que quatro voluntários do sexo feminino e um do sexo masculino foram capazes de identificar, através de dados obtidos com o EEG, as diferentes dosagens de sacarose. Os resultados permitem concluir que o modelo de análise sensorial proposta, com a utilização de EEG, para avaliar os estímulos gustativos no contexto cognitivo foi satisfatória e permitiu com a utilização de processamento de sinais digitais e AGR (Análise Adaptativa de Gabor) quantificar com eficiência a percepção dos voluntários as diferentes dosagens apresentadas no experimento. Sugere-se que as diferentes percepções dos voluntários no geral, encontradas no EEG, representam as suas singularidades quanto aos significados atribuídos ao sabor e suas correlações. / The growing concern with the development of healthy habits and a balanced diet allows the progress in Food Science as well as in the relationship between human beings and food. In the last decades the quality of the sensorial analysis has been studied not based only on the interaction between human beings and food but also through the comprehension of subjective and emotional factors that influence customers. The interest in emotional aspects which influence such choices extends the studies to the field of Psychological Science that attempts to understand neurocognitive and analytical bases of brain functioning as motivating elements of those human processes. The work in Cognitive Neuroscience has glimpsed new paradigms due to the development of new techniques about brain observation with the purpose of getting to know its structure and function other than allowing the association of behavior observed experimentally or clinical behavior not considering only a presumed mental correlative but also specific markers of mental activity observed in advance. In that aspect the brain electrical activity acquired through electroencephalogram has been recently used to monitor brain events. Therefore, the aim of this work is to propose a sensorial analysis pattern which allows to evaluate quantitatively the action of taste stimuli within a cognitive context using electroencephalogram. The experiment was carried out in the Laboratory of Applied and Computational Physics (LAFAC) in the University of the State of São Paulo (USP), Pirassununga Campus, from May 2011 to May 2012 with 23 volunteers (13 women and 10 men) aging between 19 and 21 years old. The volunteers\' electroencephalogram signals were collected when they tasted 27 sweet flavored samples, being 9 of them with 0% of sucrose (water), 9 with 0.15% of sucrose (threshold), and 9 with 5% of sucrose (maximum concentration). Seven volunteers were selected from this experiment (5 women and 2 men) whose data was analyzed. In this study was found that four women and one man were able to identify, through the EEG data obtained with the different concentrations of sucrose. The results obtained allowed to conclude that the proposed sensorial analysis pattern using electroencephalogram to evaluate taste stimuli within the cognitive context was satisfactory and allowed, along with the use of digital signals processing and Gabor Adaptive Analysis (AGR), to analyze and to quantify efficiently the volunteers\' perception of different doses presented in the experiment. It is suggested that the different perceptions of volunteers in general, encountered in EEG, representing singularities as to the meanings attributed to taste and their correlations.
140

Efeitos das verbalizações do autoclítico \"E\" durante treinos e testes de discriminações condicionais e de relações de equivalência / Effects of autoclitic verbalizations \"IS\" during drills and tests of conditional discriminations and equivalence relations

Martins, Luis Antonio Lovo 06 June 2019 (has links)
Com o número crescente de pesquisas sobre a formação de discriminações condicionais e de equivalência de estímulos, outras explicações, além daquelas relacionadas ao reforçamento diferencial, surgiram. Tais estudos passaram a sugerir que o comportamento verbal poderia facilitar a formação do responder discriminativo e da equivalência de estímulos. Porém, poucas tem sido as pesquisas que se concentraram em investigar, especificamente, o efeito do comportamento verbal autoclítico relacional/qualificador neste responder. O objetivo da presente pesquisa foi analisar se uma instrução que orientou os participantes a emitir uma resposta verbal vocal com autoclítico relacional/qualificador é e uma instrução que orientou os participantes a emitirem uma resposta verbal concorrente (entre a apresentação do estímulo modelo e a resposta de escolha do estímulo comparação, em uma tarefa de matching to sample) produzem efeitos na formação de classes de equivalência e se influencia na quantidade de tentativas necessárias para a formação do responder discriminativo condicional. Foram estudados vinte e cinco participantes adultos, divididos em três grupos: Grupo Controle 1, Grupo Controle 2 e Grupo Experimental. Todos os participantes foram submetidos a três treinos de discriminações condicionais (AB, BC e CD) e a dois testes de equivalência (AD e DA). Cada conjunto continha três estímulos visuais abstratos e cada treino foi composto por doze tentativas. O critério de aprendizagem era a ocorrência de uma sequência de 100% de respostas corretas no treino. A instrução com o autoclítico relacional/qualificador foi apresentada apenas aos participantes do Grupo Experimental e a instrução contendo a resposta verbal concorrente foi apresentada apenas aos participantes do Grupo Controle 2. Os resultados obtidos nos treinos de discriminações condicionais mostram um desempenho semelhante entre os participantes do Grupo Controle 1 e 2 e um desempenho inicial otimizado dos participantes do Grupo Experimental. Nos testes de equivalência de estímulos foi observado um índice superior de resultados positivos para os participantes do Grupo Experimental, em relação aos participantes dos Grupos Controle 1 e 2. A verbalização do autoclítico relacional/qualificador auxiliou os participantes do Grupo Experimental a estabelecerem o controle de estímulos planejado, já que todos os participantes emitiram a resposta verbal vocal este é este, acompanhado da resposta de escolha correta, reforçada diferencialmente. A análise dos Grupos Controle 1 e 2 permitiu a discussão sobre o papel do comportamento verbal na aquisição de relações condicionais e na formação de classes de equivalência, já que no Grupo Controle 1 os participantes permaneceram em silêncio, em contraste com os participantes do Grupo Experimental / With the increasing number of researches on the formation of conditional discriminations and stimulus equivalence, other explanations, in addition to those related to differential reinforcement, have emerged. Such studies have suggested that verbal behavior could facilitate the formation of discriminative response and the equivalence of stimuli. However, few studies have focused on investigating, specifically, the effect of verbal behavior autoclitic relational/qualifying in responding. The purpose of the present research was to analyze whether an instruction that instructed the participants to issue a verbal vocal response with autoclitic relational/qualifying \"is\" and an instruction that instructed the participants to issue a concurrent verbal response (between the presentation of the model stimulus and the response of choice of the stimulus comparison, in a matching to sample task) produce effects on the formation of equivalence classes and influence the amount of attempts required for the formation of conditional discriminative response. Twenty-five adult participants were studied, divided in three groups: Control Group 1, Control Group 2 and Experimental Group. All participants underwent three conditional discriminations (AB, BC and CD) and two equivalence tests (AD and AD). Each set contained three abstract visual stimuli and each training consisted of twelve attempts. The learning criterion was the occurrence of a sequence of 100% correct answers in the training. The instruction with the autoclitic relational/qualifying was presented only to the participants of the Experimental Group and the statement containing the concurrent verbal response was presented only to the participants of the Control Group 2. The results obtained in the conditional discrimination training show a similar performance among the participants of the Control Group 1 and 2 and an optimized initial performance of the participants of the Experimental Group. In the equivalence tests of stimuli, a superior index of positive results was observed for the participants of the Experimental Group, in relation to the participants of the Control Groups 1 and 2. The verbalization of the autoclítico relational/qualifying helped the participants of the Experimental Group to establish the control of stimuli planned, since all the participants issued the vocal verbal response \"this is this\", accompanied by the correct choice answer, differentially reinforced. The analysis of Control Groups 1 and 2 allowed the discussion about the role of verbal behavior in the acquisition of conditional relations and in the formation of equivalence classes, since in Control Group 1 the participants remained silent, in contrast to the participants of the Experimental Group

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