745 resultados para Simetria discreta


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Trace gases are important to our environment even though their presence comes only by ‘traces’, but their concentrations must be monitored, so any necessary interventions can be done at the right time. There are some lower and upper boundaries which produce nice conditions for our lives and then monitoring trace gases comes as an essential task nowadays to be accomplished by many techniques. One of them is the differential optical absorption spectroscopy (DOAS), which consists mathematically on a regression - the classical method uses least-squares - to retrieve the trace gases concentrations. In order to achieve better results, many works have tried out different techniques instead of the classical approach. Some have tried to preprocess the signals to be analyzed by a denoising procedure - e.g. discrete wavelet transform (DWT). This work presents a semi-empirical study to find out the most suitable DWT family to be used in this denoising. The search seeks among many well-known families the one to better remove the noise, keeping the original signal’s main features, then by decreasing the noise, the residual left after the regression is done decreases too. The analysis take account the wavelet decomposition level, the threshold to be applied on the detail coefficients and how to apply them - hard or soft thresholding. The signals used come from an open and online data base which contains characteristic signals from some trace gases usually studied.

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This Thesis comprises a theoretical study about the influence of the magnetocrystalline anisotropy on the static and dynamic magnetic properties of nanofilms: monolayers and trilayers coupled through the bilinear and biquadratic exchange fields, for situations in which the systems are grown in unusual [hkl] asymmetric directions. Using a theory based on a realistic phenomenological model for description of nanometric systems, we consider the total free magnetic energy including the Zeeman interaction, cubic and uniaxial anisotropies, demagnetizing and surface anysotropy energies, as well as the exchange terms. Numerical calculations are conducted by minimizing the total magnetic energy from the determination of equilibrium static configurations. We consider experimental parameters found in the literature to illustrate our results for Fe/Cr/Fe trilayer systems. In particular, a total of six different magnetic scenarios are analyzed for three regimens of exchange fields and the [211] and [321] asymmetric growth directions. After numerically minimize the total energy, we use the equilibrium configurations to calculate magnetization and magnetoresistance curves with the respective magnetic phases and corresponding critical fields. These results are also used to establish the boundary for occurrence of saturated states. Within the context of the spin waves, we solve the equation of motion for these systems in order to find the respective associated dispersion relations. The results show similar magnetization and magnetoresistance curves for both [211] and [321] growth scenarios, including an equivalent magnetic transition behavior. However, the combination of those peculiar symmetries and influence of the exchange energies results in attractive properties, including the generation of magnetic states as a function of the asymmetric degree imposed in the [hkl] growth orientations. There is also an increasing incompatibility between the values of saturation fields of magnetization and magnetoresistance for the cases in which a magnetic field acts along intermediate cubic anisotropic axes, particularly in the situations where the bilinear and biquadratic exchange fields are comparable. The dispersion relations and static results are consistent, the corresponding magnetic states are also present in both acoustic and optical modes. Furthermore, Goldstone excitations are also observed for that particular cases of a magnetic field acting in the intermediate axes, an effect related to transitions of second order and to the spontaneous symmetry breaking imposed by the combination of the biquadratic energy with the cubic and uniaxial anisotropies.

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Photodynamic therapy (PDT) consists of a non-toxic photosensitizing agent (FS) administration followed by a laser source resulting in a sequence of photochemical and photobiological processes that generate reactive oxygen species (ROS) that damaging cells. The present work evaluated the effects of PDT nanoemulsion-aluminum chloride phthalocyanine (AlClFc) mediated on malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels, which represent indicators involved in oxidative stress and antioxidant defenses. For this purpose, this study used 120 female rats of the Rattus norvegicus species, Wistar race, divided into 5 groups: Healthy (H), with periodontal disease (PD), with periodontal disease and treatment with FS (F), with periodontal disease and treatment with the laser (L); and periodontal disease and treatment with PDT (FL). An experimental model for represent periodontal disease (PD) was induced by ligature (split-mouth). Seven days later the induction of PD, the treatments were instituted according to the groups. In the group treated with PDT was applied 40μl FS (5μM) followed by laser irradiation diode InGaAlP (660nm, 100J / cm2). The rats were sacrificed on the 7th and 28th day after treatment and tissue specimens were removed and subjected to histological, immunohistochemical methods and enzymatic colorimetric measurements with detection by UV / VIS spectroscopy. Inflammatory changes, connective tissue disorganization and alveolar bone loss were displaying in groups with PD induced. The enzyme dosages showed that MDA levels were higher in PD induced groups, with no statistically significant differences (p> 0.05). High levels of GSH were found in groups L (p = 0.028) and FL (p = 0.028) compared with PD group, with statistically significant differences. Immunohistochemistry for SOD showed higher immunostaining in L and FL groups, compared to the PD group without statistically significant differences (p> 0.05). GPx showed lower immunoreactivity in the DP group when compared to the other groups and statistically significant differences were observed between the DPxL groups (p <0.05). TFD administered in this experiment did not induce elevation of MDA levels significantly increased the GSH levels and showed intense immunostaining pada SOD and GPx, showing that this therapy does not accentuated lipid peroxidation, however, it was able to induce effects on the antioxidant defenses processes. The LBI therapy appeared to show photomodulatory promoting effects reduction of the MDA levels, increasing GSH levels and with intense immunostaining for SOD and GPx, demonstrating that laser therapy induced antioxidant effects.

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CHAPTER II - The Chrysocyon brachyurus is the biggest South American canid which has a high frequency of dental injuries, both in wild and captivity. Thus, veterinary procedures are necessary to preserve the feeding capacity of hundreds of captive specimens worldwide. The aim of this study was to study the mandibular morphometry of maned wolf with emphasis on the establishment of anatomic references to the anesthetic blockage of the inferior alveolar and mental nerves. Therefore, 15 measurements in 22 hemimandibles of C. brachyurus adults were taken. For extra-oral technique of blockage of the inferior alveolar nerve at the level of the mandibular foramen, it is stated that the needle should be advanced, close to the medial surface of the mandibular ramus, by 11.4 mm perpendiculary from the palpable concavity. Alternatively, the needle can be introduced for 30.4 mm from the angular process at 20-25 degrees angle with the ventral margin. For blocking only the mentual nerve, it is recommended the introduction of needle for 10 mm, close to the lateral aspect of the mandibular body, at the level of the lower first premolar. The mandibular foramen showed similars position, size and symmetry in the maned wolfs specimens examined. The comparison of the data with those available for other carnivores reflects the necessity for determining these anatomical references specifically for each species.

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Esta pesquisa busca abordar e analisar os caminhos da mídia televisiva nas igrejas Assembleias de Deus no Brasil, aqui trabalhadas no plural devido às muitas ramificações da denominação, em suas construções das representações simbólicas, imaginárias, culturais e midiáticas. O objetivo é analisar a dimensão simbólica na proibição do uso da televisão na denominação religiosa em questão, e os argumentos para o veto entre os fiéis, a discreta aceitabilidade da TV diante das novas concepções teológicas das ADs ao longo dos anos, investimento em canal aberto (Rede Boas Novas de Televisão) e proposta de um programa televisivo como marca midiática da denominação (Programa Movimento Pentecostal). Para viabilidade desse trabalho, a metodologia adotada consiste em pesquisa bibliográfica histórica, com foco nos temas fundamentais para o desenvolvimento das pesquisas do imaginário, identidade, cultura, nação e televisão, aliada à pesquisa documental, que tem como meta os registros históricos, que melhor elucidarão os caminhos e a ligação da TV com as Assembleias de Deus.

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Se presenta aquí la tesis doctoral titulada “Evolución histórica de las investigaciones sobre la morfología del cuerpo vítreo humano en la Edad Contemporánea”. Se trata de un estudio pionero —en la línea del tiempo— sobre los descubrimientos más importantes en la estructura del cuerpo vítreo humano, donde se lleva a cabo una innovadora periodización histórica orientada al desarrollo de las investigaciones. Debido a que el cuerpo vítreo es prácticamente transparente y está basado en una estructura fina y discreta, ha sido una parte del cuerpo humano difícil de estudiar y comprender. Además, al estar incluido dentro del ojo humano, ha habido grandes dificultades para su acceso in vivo. Sin embargo, con el avance en la microscopía y las técnicas histológicas, es a partir de mediados del siglo XIX cuando se comienza a estudiar con interés su morfología. Por otra parte, con la influencia de las primeras observaciones de la patología del vítreo y la retina utilizando el oftalmoscopio, y el desarrollo de la lámpara de hendidura, emergieron nuevas interpretaciones de la morfología in vivo desde el final de la Gran Guerra (1918). En particular, es a partir de 1945 cuando la investigación sobre esa estructura comenzó a ser numerosa, profunda y a dar sus frutos...

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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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The aim of this paper is to deepen in the terminology of Records Management established by ISO standards, through a concrete example such as an interlinguistic comparison between UNE ISO 15489-1 and DIN ISO 15489-1, that is, between the Spanish and German versions of the ISO 15489-1. For that, the text is divided into two major and complementary parts, which are similar to both analytical perspectives adopted: the semantic one and the pragmatic one. The first one compares the words per se, taking into account the significant or word form as well as the significance or meaning. In the second part, examples of use from both languages are discussed, concerning the three terms considered essential in the text (Record, Records Management System and Records Management). The main conclusion lies in understanding how important the language is as a discrete tool of work for all information scientists, specially concerning to the standards, where the translators must show their best linguistic strategies to go unnoticed.

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This paper aims to investigate the use of collocations in DELE B1. We select the reading texts from DELE B1 (2010 to 2014) as research data. The investigation includes: First of all, we will study the theory of collocation and the classification as well as its application to the foreign language learning and teaching. Second, we will analyze the types of collocation annotated by Corpus Tool. Third, we tend to calculate the frequency use of each type of collocations written in Spanish reading texts. Next, we will discuss the interrelationship between collocations and text themes. Finally, we would like to compare the differences of results of collocation use between these two corpus tools: Corpus Tool and Corpus del Español in order to understand the native speakers’ preference of use collocations as well as to provide supplementay materials for teaching of Spanish reading. We hope that the expected results of our research will offer useful references for improving students' Spanish reading comprehension to pass DELE B1 examinations.

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Serão analisados aspectos históricos e estruturais dos quadrados mágicos e apresentados os materiais resultantes dessa investigação para efeito da composição de uma obra para coro, solistas e orquestra, a Paixão . O quadrado mágico, um dispositivo de características de construção matemáticas, adquiriu contornos místicos ao longo da história, por suas propriedades de simetria e beleza. O processo criativo dentro de uma perspectiva determinística, procura analisar o papel de estruturas pré-estabelecidas para a obtenção de materiais destinados a integrar o repertório de elementos pré-composicionais.

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Programa de doctorado: Economía: aplicaciones a las finanzas y seguros, a la economía sectorial, al medio ambiente y a las infraestructuras. La fecha de publicación es la fecha de lectura

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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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A pesar del elevado crecimiento de la economía peruana en los últimos diez años, los profesionales universitarios se enfrentan a dificultades cada vez mayores para desempeñarse en ocupaciones laborales acorde a su formación educativa superior, habilidades e inversiones educativas. Este panorama se concreta en la condición "subempleo profesional" por la cual cuatro de cada diez profesionales universitarios al 2012 se encuentran sobre-educados, ocupando vacantes no profesionales y subremunerados. Proponemos que el deterioro en la calidad de la educación superior universitaria ha sido un desencadenante del aumento de profesionales universitarios subempleados, como alternativa a la literatura que analiza causas relacionadas a la demanda laboral. El objetivo principal de esta investigación consiste en explorar y cuantificar en qué medida la calidad de la educación superior contribuye al subempleo profesional en el Perú. Usando datos de la Encuesta Nacional de Hogares (ENAHO) y el Censo Nacional Universitario (CENAUN) de los años 1996 y 2010, planteamos un modelo de elección discreta que mide los efectos de la calidad universitaria sobre la condición individual de subempleo en un horizonte de largo plazo. La fuente de variabilidad que permite identificar dichos efectos es el proceso de apertura y desregulación del mercado de universidades iniciado en la década de los noventa. Nuestros resultados indican que la probabilidad de estar subempleado, para los profesionales que asistieron a universidades de «menor calidad», aumentó de 0.19 a 030 a partir de la desregulación del mercado universitario —tomando en cuenta que la desregulación afectó tanto la calidad de la universidad a la que se asistió como la posibilidad de adquirir educación superior universitaria en general para los individuos con menores habilidades académicas.

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Reinforced concrete creep is a phenomenon of great importance. Despite being appointed as the main cause of several pathologies, its effects are yet considered in a simplified way by the structural designers. In addition to studying the phenomenon in reinforced concrete structures and its current account used in the structural analysis, this paper compares creep strains at simply supported reinforced concrete beams in analytical and in experimental forms with the finite element method (FEM) simulation results. The strains and deflections obtained through the analytical form were calculated with the Brazilian code NBR 6118 (2014) recommendations and the simplified method from CEB-FIP 90 and the experimental results were extracted from tests available in the literature. Finite element simulations are performed using ANSYS Workbench software, using its 3D SOLID 186 elements and the structure symmetry. Analyzes of convergence using 2D PLANE 183 elements are held as well. At the end, it is concluded that FEM analyses are quantitative and qualitative efficient for the estimation of this non-linearity and that the method utilized to obtain the creep coefficients values is sufficiently accurate.

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Serão analisados aspectos históricos e estruturais dos quadrados mágicos e apresentados os materiais resultantes dessa investigação para efeito da composição de uma obra para coro, solistas e orquestra, a Paixão . O quadrado mágico, um dispositivo de características de construção matemáticas, adquiriu contornos místicos ao longo da história, por suas propriedades de simetria e beleza. O processo criativo dentro de uma perspectiva determinística, procura analisar o papel de estruturas pré-estabelecidas para a obtenção de materiais destinados a integrar o repertório de elementos pré-composicionais.