999 resultados para Reação comportamental


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Parkinson disease (PD) is associated with motor symptoms and dopaminergic cell loss in the nigrostriatal pathway. Alpha-synuclein is the major component of the Lewy bodies, the biological hallmarks of disease, and has been associated with familial cases of PD. Recently, the spinal cord stimulation (SCS) showed to be effective to alleviate the Parkinson symptoms in animal models and human patients. In this project, we characterized the motor and electrophysiological effects of alpha-synuclein overexpression in the substantia nigra of rats. We further investigated the effects of spinal electrical stimulation, AMPT and L-dopa administration in this model. Method: Sprague-Dawley rats were injected with empty viral vector or the vector carrying the gene for alpha-synuclein in the substantia nigra, and were tested weekly for 10 weeks in the open field and cylinder tests. A separated group of animals implanted with bilateral electrode arrays in the motor cortex and the striatum were recorded in the open field, during the SCS sessions and the pharmacological experiments. Results: Alpha-synuclein expression resulted in motor asymmetry, observed as the reduction in use of contralateral forepaw in the cylinder test. Animals showed an increase of local field potential activity in beta band three and four weeks after the virus injection, that was not evident after the 5th week. AMPT resulted in a sever parkinsonian state, with reduction in the locomotor activity and significant peak of oscillatory activity in cortex and striatum. SCS was effective to alleviate the motor asymmetry at long term, but did not reduce the corticostriatal low frequency oscillations observed 24 hs after the AMPT administration. These oscillations were attenuated by L-dopa that, even as SCS, was not effective to restore the locomotor activity during the severe dopaminergic depletion period. Discussion: The alpha-synuclein model reproduces the motor impairment and the progressive neurodegenerative process of PD. We demonstrated, by the first time, that this model also presents the increase in low frequency oscillatory activity in the corticostriatal circuit, compatible with parkinsonian condition; and that SCS has a therapeutic effect on motor symptom of this model.

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Sulfur compounds emissions have been, on the late years, subject to more severe environmental laws due to its impact on the environment (causing the acid rain phenomena) and on human health. It has also been object of much attention from the refiners worldwide due to its relationship with equipment’s life, which is decreased by corrosion, and also with products’ quality, as the later may have its color, smell and stability altered by the presence of such compounds. Sulfur removal can be carried out by hydrotreating (HDT) which is a catalytic process. Catalysts for HDS are traditionally based on Co(Ni)-Mo(W)/Al2O3. However, in face of the increased contaminants’ content on crude oil, and stricter legislation on emissions, the development of new, more active and efficient catalysts is pressing. Carbides of refractory material have been identified as potential materials for this use. The addition of a second metal to carbides may enhance catalytic activities by increasing the density of active sites. In the present thesis Mo2C with Co addition was produced in a fixed bed reactor via gas-solid reaction of CH4 (5%) and H2(95%) with a precursor made of a mix of ammonium heptamolybdate [(NH4)6[Mo7O24].4H2O] and cobalt nitrate[Co(NO3)2.6H2O] at stoichiometric amounts. Precursors’ where analyzed by XRF, XRD, SEM and TG/DTA. Carboreduction reactions were carried out at 700 and 750°C with two cobalt compositions (2,5 and 5%). Reaction’s products were characterized by XRF, XRD, SEM, TOC, BET and laser granulometry. It was possible to obtain Mo2C with 2,5 and 5% cobalt addition as a single phase at 750°C with nanoscale crystallite sizes. At 700°C, however, both MoO2 and Mo2C phases were found by XRD. No Co containing phases were found by XRD. XRF, however, confirmed the intended Co content added. SEM images confirmed XRD data. The increase on Co content promoted a more severe agglomeration of the produced powder. The same effect was noted when the reaction temperature was increased. The powder synthesized at 750°C with 2,5% Co addition TOC analysis indicated the complete conversion from oxide material to carbide, with a 8,9% free carbon production. The powder produced at this temperature with 5% Co addition was only partially converted (86%)

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This work proposes the use of the behavioral model of the hysteresis loop of the ferroelectrics capacitor as a new alternative to the usually costly techniques in the computation of nonlinear functions in artificial neurons implemented on reconfigurable hardware platform, in this case, a FPGA device. Initially the proposal has been validated by the implementation of the boolean logic through the digital models of two artificial neurons: the Perceptron and a variation of the model Integrate and Fire Spiking Neuron, both using the model also digital of the hysteresis loop of the ferroelectric capacitor as it’s basic nonlinear unit for the calculations of the neurons outputs. Finally, it has been used the analog model of the ferroelectric capacitor with the goal of verifying it’s effectiveness and possibly the reduction of the number of necessary logic elements in the case of implementing the artificial neurons on integrated circuit. The implementations has been carried out by Simulink models and the synthesizing has been done through the DSP Builder software from Altera Corporation.

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The study of chemical reactions is among the most important contents to the understanding of Chemistry discipline in basic education. However, there are still few studies about chemical reactions as a complex system because, generally, this content is presented in textbooks, taught and even researched in a fragmented form. The thesis here presented aims to investigate, identify and characterize the mistakes and learning difficulties of the students about chemical reactions as a complex system, using for that purpose the analysis of the answers of 126 exams of candidates for the bachelor’s degree in Chemistry Teaching on the entrance exam for the Federal University of Rio Grande do Norte (UFRN). The mistakes and learning difficulties about the parameters ΔG°, Kp, Ea and of the calculation of the amount of substance in a chemical reaction have been identified, as well as the levels of development of the ability to interpret the chemical reaction as a system. The main theoretical source of this study is structured based on the mistakes and learning difficulties (NÚÑEZ, RAMALHO, 2012), of the chemical reactions as complex systems (NÚÑEZ, 1994; RESHETOVA, 1988; SANDERSON, 1968). As methodology, it was prioritized the analysis of the answers to the exams and the interview with the teachers. The results showed typical mistakes in the study of this subject, especially low levels and skill development. No student was able to integrate the different aspects in the systemic understanding of the chemical reaction. From the interviews with Chemistry teachers from High School, it was determined the reasons the teachers assign to those mistakes and learning difficulties. The interviews revealed that the teachers do not work in the perspective of integration of the contents which leads the students to present difficulties and make mistakes related to the content previously mentioned. The study presents a proposal for the organization of the contents of Chemistry discipline for High School as a possibility of a dialectic systemic integration of contents, understanding that this systematic vision, leads to important contributions to the development of the theoretical thinking of the students. We can mention as one of the conclusions of this study, the fact that the non-systemic organization of contents do not favor this kind of thinking in students.

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O autismo é um transtorno do desenvolvimento que se manifesta nos primeiros anos de vida e apresenta semiologia heterogênea. Esta patologia afeta a maturação do encéfalo e produz alterações sensoriais, de linguagem e de interação social no início na infância. O modelo experimental de autismo utilizando ácido valproico (VPA) durante o período gestacional tem sido demonstrado ter alta validade de face e permitir estudos tanto das bases neuropatológicas quanto neuro-funcionais durante o desenvolvimento. A despeito do recente interesse por este modelo como instrumento de compreensão dos aspectos básicos da fisiopatologia do autismo, a maioria dos estudos experimentais têm se concentrado nos aspectos comportamentais, histológicos e celulares. Neste trabalho, foram propostas estratégias experimentais de avaliação comportamental associadas a eletrofisiologia \textit{in vivo}, uma técnica que nunca fora utilizada para avaliação desse modelo. Animais controles e experimentais, submetidos previamente a um procedimento cirúrgico para implante de eletrodos crônicos, participaram de experimentos de livre exploração, interação social e condicionamento ao medo.

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Coffee plants were introduced in Brazil in the Northern State of Para around 1727. Two major diseases have affected coffee trees in the country. One is rust, caused by fungus Hemileia vastatrix and accountable for production losses up to 50%. The other one is Cercospora leaf spot, caused by fungus Cercospora coffeicola endemic to all Brazilian coffee farms and, therefore, economically critical due to production losses both in the plant nursery and in the field. Availability of resistant varieties has been a constant challenge for breeders. Research programs play an important role in the search for new resistant and/or tolerant genotypes, since over time plants can become susceptible to new, genetically variable races of pathogens. This study aimed to evaluate the incidence and severity of such diseases, the resistance of different coffee genotypes to H. vastatrix and C. coffeicola pathogens, as well as the productivity of said genotypes in dense planting system. The experimental design consisted of randomized blocks, with twelve genotypes (treatments) and two replications (blocks). SISVAR® program was used to analyze data and compare them building on Scott-Knott test and Tukey’s test with a probability of 5%. Disease incidence and severity percentage were assessed for both Cercospora leaf spot and rust. Means were used to calculate the area under the disease progress curve (AUDPC) of both diseases. As to rust, the most resistant genotypes were H586-6, IBC 12, and H556-7 H567-6. As to Cercospora leaf spot and productivity, no statistical differences were found across genotypes. The dense planting system did not impair plant development, but favored disease evolution given the microclimate it produces.

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Personality is one of the most controversial and intriguing theme in Psychology. In a general way, it could be understood as a set of rigid patters of feelings, thoughts, and behaviors from an individual. The aim of this investigation was describe how Brazilian researches in Psychology that use cognitive, behavioral, and cognitive-behavioral therapy referential have been approaching the subject Personality in their work. We also intended to determine the frequency of publications on Personality Disorders to compare this data with the bibliographical production on Anxiety and Mood Disorders. Moreover, we tried to describe how the Personality construct - and even Personality Disorders construct - has been addressed in the work on the Anxiety and Mood Disorders chosen for this review. The PePSIC Periódicos Eletrônicos em Psicologia - e SciELO.ORG - Scientific Electronic Library Online - databases were used for research. We investigated 53 journals, including two specific Cognitive Therapies and Behavioral-Cognitive Therapy (TCC) periodicals. Within each journal, we undertook a systematic survey on publications on the themes: Personality, Personality Disorder, Panic Disorder, Social Phobia, Obsessive-Compulsive Disorder (OCD), Generalized Anxiety Disorder, Major Depression, Dysthymia and Bipolar Disorder. A preliminary research has resulted in 218 articles. A second filter has obtained 81 articles in which we the focused on this review. There were found thirty-eight articles on Anxiety Disorders, twenty-five on Mood Disorders and eighteen on Personality Disorders. It was found that 90% of the papers on Anxiety Disorders make no reference to the term Personality or make it in a discrete way. This number rises to 96% to Personality Disorder group. Analyzing the specific journals on TCC we verified that 97% of the articles on Anxiety and Humor disorders do not cite the term Personality or cite but not explore it. This results point to the low rate of studies addressing the Personality and personality disturbs. Then, we can suggest that the difficulty on treating this Axis II disturbs has been worsened by lack of knowledge produced on the subject, either for lack of interest among researchers or because of the methodological obstacles found on this field.

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Algumas pesquisas demonstram que a presença de um parceiro social durante uma situação de risco modula a resposta ao estresse, atenuando seus efeitos negativos. Neste estudo, 8 díades de machos e 8 de fêmeas de sagüi comum (Callithrix jacchus) foram expostos a um ambiente novo, sozinhos e acompanhados de um parceiro de mesmo sexo e idade. Quando submetidos a um ambiente novo em companhia de um animal de mesmo sexo, os machos apresentaram um perfil mais filiativo enquanto as fêmeas foram mais competitivas entre si. Os resultados mostram que a resposta comportamental é sexualmente dimórfica, e que machos e fêmeas utilizam diferentes estratégias quando confrontados com situações desafiadoras no ambiente natural Abstract Some researches demonstrate that the presence of a social partner during a challenging situation modulates the stress response, decreasing its negative effects. In this study common marmoset (Callithrix jacchus) males and females were exposed to a new environment, alone or in companion of a social partner of the same sex and age. When submitted to new environment in companion of a same-sex social partner males showed more affiliation whereas females performed agonistic behaviors. The results show that behavioral response is sexually dimorphic and that males and females used different strategies when facing challenging situations in natural conditions

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AZEVEDO, Luciana Karla Araújo de, et al. Caracterização e correlação do fenômeno pró-zona com títulos de sororeatividade do VDRL e reação de imuno-fluorescência indireta em soros de pacientes com sífilis. Revista Brasileira de Análises Clínicas, Rio de Janeiro, v. 38, n. 2, p. 183-187, 2006.

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Objetivos: A institucionalização é, habitualmente, um momento gerador de sentimentos negativos, tais como a perda e o abandono, fragilizando os jovens envolvidos neste processo e, eventualmente, condicionando o seu funcionamento emocional, comportamental e social. O nosso estudo tem como objetivos: 1) verificar a existência de diferenças entre uma amostra de jovens institucionalizados e uma amostra de jovens não institucionalizados nas dimensões de um instrumento que avalia o funcionamento social, comportamental e emocional (Roberts Apperception Test for Children/RATC) e na autoestima (Rosenberg Self Esteem Scale/RSES); 2) explorar se existem diferenças entre as duas amostras ao nível de diferentes variáveis sociodemográficas, familiares e clínicas (e.g. história de sintomas depressivos em toda a vida e atual). Método: A amostra é composta por 60 jovens, 30 não institucionalizados (subamostra de controlo) e 30 institucionalizados (entre os 10 e os 15 anos de idade). A amostra de controlo respondeu a um questionário sociodemográfico e à Rosenberg Self Esteem Scale (RSES). Os jovens institucionalizados responderam a esta escala e a algumas perguntas do questionário sociodemográfico, tendo outras sido completadas com base nos processos da instituição. O autor administrou, junto das duas subamostras, o Roberts Apperception Test for Children (RATC). Resultados: Não foram encontradas diferenças estatisticamente significativas entre as duas amostras, no que diz respeito à RSES. Quanto ao RATC, foram encontradas diferenças estatisticamente significativas no que diz respeito apenas a quatro dimensões: Suporte aos outros, Identificação de problemas, Resolução 2 e Problema não resolvido. Verificaram-se associações significativas entre a pertença a uma ou outra subamostra e algumas variáveis sociodemográficas e clínicas, por exemplo, a escolaridade do pai e da mãe e a vivência de sintomatologia depressiva em toda a vida. Conclusões: No geral, o funcionamento emocional, social e comportamental, assim como a autoestima de jovens institucionalizados parece não se diferenciar grandemente dos de jovens não institucionalizados. Ainda assim, os jovens institucionalizados parecem apresentar resultados menos adaptativos em algumas dimensões, por comparação com os jovens institucionalizados.

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Introdução: A Anorexia Nervosa (AN) é a perturbação do comportamento alimentar (PCA) com a maior taxa de mortalidade de todos os transtornos psiquiátricos. Carateriza-se pela recusa em manter um peso corporal normal mínimo, pela distorção da imagem corporal e por um obsessivo medo de ganhar peso. Os comportamentos patológicos a ela associados podem levar a uma semi-inanição que necessita de cuidados médicos pluridisciplinares, muitas vezes, em regime de internamento. Vários ensais clínicos avaliaram a eficácia da Terapia Cognitivo- Comportamental (TCC), indicando que ela favorece a remissão ou a diminuição da frequência de episódios de compulsão alimentar, dos comportamentos purgativos e da restrição alimentar. Objetivo: Combinar os resultados da melhor evidência científica de forma a avaliar a eficácia da TCC em comparação com outras terapias utilizadas no tratamento da AN. Métodos: A pesquisa realizou-se nas bases de dados eletrónicas da MEDLINE, Psyc-Info, Embase, CCTR e de forma manual, incluindo ensaios clínicos controlados randomizados que comparam a TCC com qualquer outro tipo de intervenção no tratamento da AN. Resultados: Foram incluídos 10 estudos que envolveram 957 pacientes: dos quais 571 (59,7%) foram submetidos a tratamento com Terapia cognitivo comportamental e 556 (49,3%) a outras terapias. Não se registaram diferenças significativas nos resultados obtidos em diversos outcomes, exceto nas subescalas Restrições (z=3,03; p=0,02), Preocupações alimentares (z=2,98; p=0,002) e Preocupações com a forma (z=1,71; p=0,09) do EDE e nos scores da escala GAF (z=1,87; p=0,06). Registaram-se diferenças estatisticamente significativas no número de episódios bulímicos (z=2,61; p=0,009), número de episódios de indução de vómito (z=2,11; p=0,03) e no número de episódios de uso indevido de laxantes (z=3,04; p=0,002). Conclusão: A utilização da Terapia Cognitivo-Comportamental no tratamento de doentes com AN parece melhorar bastante os sintomas da doença, revelando-se particularmente eficaz nos resultados obtidos na Eating Disorder Examination Scale. A sua utilização parece levar a uma melhoria no scores da GAF, evidenciando uma melhoria geral do estado de saúde dos pacientes (redução dos episódios de vómito, bulimia e uso de laxantes). / Página | viii ABSTRACT Background: Anorexia Nervosa is an eating disorder with the highest mortality rate of all psychiatric disorders. It is characterized by refusal to maintain a minimally normal body weight, the distortion of body image and obsessive fear of gaining weight. The pathological behaviors associated with it can lead to semi-starvation, requiring medical treatment and multidisciplinary inpatient care. Several clinical trials evaluated the efficacy of Cognitive Behavioral Therapy (CBT) in lead to remission or reduction of the frequency of bingue eating episodes, purgative behaviors and food restriction. Objective: Combining the results of the best scientific evidence to assess the efficacy of CBT in comparison with other therapies used in the treatment of AN. Methods: The research was carried out in electronic databases of MEDLINE, Psyc- Info, Embase, CCTR and manually, including randomized controlled trials that compared CBT with any other type of intervention in the treatment of AN. Results: Of which 571 (59.7%) were treated with cognitive behavioral therapy and 556 (49.3%) to other therapies: 10 studies involving 957 patients were included. No significant differences in the results obtained in different outcomes, except subscales Restrictions (z = 3.03, p = 0.02), Eating Concerns (z = 2.98, p = 0.002) and Shape Concerns (z = 1.71, p = 0.09) in the scores of EDE and the GAF scale (z = 1.87, p = 0.06). There were statistically significant differences in the number of bulimic episodes (z = 2.61, p = 0.009), number of episodes of induced vomiting (z = 2.11, p = 0.03) and the number of occurrences of use misuse of laxatives (z = 3.04, p = 0.002). Conclusion: The use of cognitive-behavioral therapy in the treatment of patients with AN seems to greatly improve the symptoms of the disease, revealing particularly effective results in the Eating Disorder Examination Scale. Its use seems to lead to an improvement in the GAF scores, showing a general improvement of the health status of patients (reduction of episodes of vomiting, bulimia and laxative use).

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The Behavioral Finance develop as it is perceived anomalies in these markets efficient. This fields of study can be grouped into three major groups: heuristic bias, tying the shape and inefficient markets. The present study focuses on issues concerning the heuristics of representativeness and anchoring. This study aimed to identify the then under-reaction and over-reaction, as well as the existence of symmetry in the active first and second line of the Brazilian stock market. For this, it will be use the Fuzzy Logic and the indicators that classify groups studied from the Discriminant Analysis. The highest present, indicator in the period studied, was the Liabilities / Equity, demonstrating the importance of the moment to discriminate the assets to be considered "winners" and "losers." Note that in the MLCX biases over-reaction is concentrated in the period of financial crisis, and in the remaining periods of statistically significant biases, are obtained by sub-reactions. The latter would be in times of moderate levels of uncertainty. In the Small Caps the behavioral responses in 2005 and 2007 occur in reverse to those observed in the Mid-Large Cap. Now in times of crisis would have a marked conservatism while near the end of trading on the Bovespa speaker, accompanied by an increase of negotiations, there is an overreaction by investors. The other heuristics in SMLL occurred at the end of the period studied, this being a under-reaction and the other a over-reaction and the second occurring in a period of financial-economic more positive than the first. As regards the under / over-reactivity in both types, there is detected a predominance of either, which probably be different in the context in MLCX without crisis. For the period in which such phenomena occur in a statistically significant to note that, in most cases, such phenomena occur during the periods for MLCX while in SMLL not only biases are less present as there is no concentration of these at any time . Given the above, it is believed that while detecting the presence of bias behavior at certain times, these do not tend to appear to a specific type or heuristics and while there were some indications of a seasonal pattern in Mid- Large Caps, the same behavior does not seem to be repeated in Small Caps. The tests would then suggest that momentary failures in the Efficient Market Hypothesis when tested in semistrong form as stated by Behavioral Finance. This result confirms the theory by stating that not only rationality, but also human irrationality, is limited because it would act rationally in many circumstances

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Algumas pesquisas demonstram que a presença de um parceiro social durante uma situação de risco modula a resposta ao estresse, atenuando seus efeitos negativos. Neste estudo, 8 díades de machos e 8 de fêmeas de sagüi comum (Callithrix jacchus) foram expostos a um ambiente novo, sozinhos e acompanhados de um parceiro de mesmo sexo e idade. Quando submetidos a um ambiente novo em companhia de um animal de mesmo sexo, os machos apresentaram um perfil mais filiativo enquanto as fêmeas foram mais competitivas entre si. Os resultados mostram que a resposta comportamental é sexualmente dimórfica, e que machos e fêmeas utilizam diferentes estratégias quando confrontados com situações desafiadoras no ambiente natural Abstract Some researches demonstrate that the presence of a social partner during a challenging situation modulates the stress response, decreasing its negative effects. In this study common marmoset (Callithrix jacchus) males and females were exposed to a new environment, alone or in companion of a social partner of the same sex and age. When submitted to new environment in companion of a same-sex social partner males showed more affiliation whereas females performed agonistic behaviors. The results show that behavioral response is sexually dimorphic and that males and females used different strategies when facing challenging situations in natural conditions

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A terapia analítico-comportamental infantil, embasada pelos pressupostos do Behaviorismo Radical e pelos princípios da Análise do Comportamento, é caracterizada por atendimento da criança em consultório e orientação de pais. Estudos têm apontado dificuldades encontradas pelos psicólogos em relação aos resultados clínicos no que se refere à generalização de ganhos terapêuticos. Apesar das investigações concluírem que os programas de intervenção com pais têm apresentado resultados satisfatórios, a prática clínica relata problemas em relação à generalização, principalmente quando avaliados ao longo do tempo. A presente pesquisa teve como objetivo compreender o processo de orientação de pais a partir de relações de elementos descritos pela literatura como influentes no processo de generalização de ganhos terapêuticos. Foi aplicado questionário, construído pela autora e sua orientadora a partir da bibliografia de referência da área estudada, com análise de especialistas e análise cognitiva dos itens (aplicação a 5 indivíduos com características semelhantes às dos nossos participantes), em 38 pais de crianças atendidas por psicólogos analistas do comportamento na cidade de Fortaleza-Ce, Brasil. Os dados foram avaliados a partir de uma análise descritiva (Tendência Central e Dispersão). Os itens do questionário foram classificados em nove categorias que foram compreendidas a partir da análise de correlação de Spearman por meio do programa estatístico SPSS. Os resultados constataram correlações positivas e significativas entre o processo de generalização e as categorias estudadas (Relação terapêutica; Ocorrência da orientação de pais; Ocorrência da generalização - Percepção dos pais; Treino de habilidades sociais para pais; Dinâmica familiar - Dificuldades no contexto familiar; Dinâmica familiar - Participação do cônjuge nos processos de orientação/generalização; Estabelecimento de regras funcionais pelos pais; Dificuldades pessoais dos pais), indicando que o psicólogo precisa avaliar e intervir nestas variáveis com o objetivo de contribuir para melhores efeitos no processo terapêutico.