96 resultados para Cordeiro - Carcaças


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As cidades são textos. Textos escritos pelas sociedades que compõe os espaços. A partir dessa perspectiva, propõe-se aqui uma leitura do bairro da Ribeira Natal/RN. Esse espaço se consolidou no início do século XX como centro comercial e cultural da capital potiguar, lugar de ação e de interação da Zona Central desta sociedade, espaço de inscrição dos signos da modernidade e do progresso então em voga. Contudo, com o decurso do tempo e as transformações por ele exigidas, o panorama da Cidade de Natal sofreu intensas modificações e o bairro da Ribeira foi relegado à margem desse processo, o que culminou na desvalorização, segregação e, posteriormente, na degradação do seu espaço, que se tornou um palimpsesto. Ao abordar a dinâmica urbana que se processou no bairro da Ribeira, esta pesquisa dividiu o fenômeno em três fases distintas: valorização, transição e decadência

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Este trabalho é uma discussão sobre as funções sociais da História e da Memória. Para tanto, foi pensado diante do 80º aniversário da Revolução de 1930, marco da (re)fundação da capital paraibana, pois esta memória e a produção historiográfica a respeito do tema nos é bastante instigante. Falar de João Pessoa, seja da cidade, seja do indivíduo; no que se refere aos episódios de 1930, é tocar em um assunto bastante passional, onde chegar a um consenso é algo extremamente improvável. O objetivo deste trabalho é problematizar as funções sociais da História e suas utilizações, notadamente por meio do nosso objeto de estudo, buscando contribuir para a compreensão de como a memória e a escrita da História são frutos do trabalho constante das sociedades que as engendram. Estudar sobre a produção da memória e da historiografia bem como a função da escrita da História sobre esses episódios, entendendo-os como espaços específicos de disputas, notadamente sobre os embates de memórias nos últimos dez anos, trazendo novas reflexões sobre as funções sociais destas memórias

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In this work we have elaborated a spline-based method of solution of inicial value problems involving ordinary differential equations, with emphasis on linear equations. The method can be seen as an alternative for the traditional solvers such as Runge-Kutta, and avoids root calculations in the linear time invariant case. The method is then applied on a central problem of control theory, namely, the step response problem for linear EDOs with possibly varying coefficients, where root calculations do not apply. We have implemented an efficient algorithm which uses exclusively matrix-vector operations. The working interval (till the settling time) was determined through a calculation of the least stable mode using a modified power method. Several variants of the method have been compared by simulation. For general linear problems with fine grid, the proposed method compares favorably with the Euler method. In the time invariant case, where the alternative is root calculation, we have indications that the proposed method is competitive for equations of sifficiently high order.

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We developed this dissertation aiming its in the process of teaching and learning of the Principle of Mathematical Induction and we set our efforts so that the students of the first year of the high school can assimilate the content having the knowledge seen in the basic education as foreknowledge. With this, we seek to awake in the student the interest on proofs, showing how much it s needed in examples that involve contents that he is already seen

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The use of non-human primates in scientific research has contributed significantly to the biomedical area and, in the case of Callithrix jacchus, has provided important evidence on physiological mechanisms that help explain its biology, making the species a valuable experimental model in different pathologies. However, raising non-human primates in captivity for long periods of time is accompanied by behavioral disorders and chronic diseases, as well as progressive weight loss in most of the animals. The Primatology Center of the Universidade Federal do Rio Grande do Norte (UFRN) has housed a colony of C. jacchus for nearly 30 years and during this period these animals have been weighed systematically to detect possible alterations in their clinical conditions. This procedure has generated a volume of data on the weight of animals at different age ranges. These data are of great importance in the study of this variable from different perspectives. Accordingly, this paper presents three studies using weight data collected over 15 years (1985-2000) as a way of verifying the health status and development of the animals. The first study produced the first article, which describes the histopathological findings of animals with probable diagnosis of permanent wasting marmoset syndrome (WMS). All the animals were carriers of trematode parasites (Platynosomum spp) and had obstruction in the hepatobiliary system; it is suggested that this agent is one of the etiological factors of the syndrome. In the second article, the analysis focused on comparing environmental profile and cortisol levels between the animals with normal weight curve evolution and those with WMS. We observed a marked decrease in locomotion, increased use of lower cage extracts and hypocortisolemia. The latter is likely associated to an adaptation of the mechanisms that make up the hypothalamus-hypophysis-adrenal axis, as observed in other mammals under conditions of chronic malnutrition. Finally, in the third study, the animals with weight alterations were excluded from the sample and, using computational tools (K-means and SOM) in a non-supervised way, we suggest found new ontogenetic development classes for C. jacchus. These were redimensioned from five to eight classes: infant I, infant II, infant III, juvenile I, juvenile II, sub-adult, young adult and elderly adult, in order to provide a more suitable classification for more detailed studies that require better control over the animal development

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Goat breeding in the state of Rio Grande do Norte, Brazil has promising economic possibilities, with the proper handling of the natural resources. The introduction of specialized animals has been one of the ways used to improve herd genetics and increase productivity. However, climate has been one of the regional factors that most interferes with the adaptation of the new genetic prevalence resulting from the introduction of exotic breeds, because in their country of origin, the air temperature during most of the year is lower than the animals body temperature. With this in mind, the aim of this study was to characterize behavioral, physiological and morphological profiles and milk production of female Saanen goats belonging to different genetic groups raised in the semi-arid region of Rio Grande do Norte in Northeast Brazil. The study was conducted in the city of Lages (5° 42 00 S and 36° 14 41 W). We used 25 lactating female Saanen goats, distributed into 3 genetic groups: 5 purebred animals, 11 three-quarter bred and 9 half-bred. Behavioral observations were made over three consecutive days in the months of August and September, between 09:00 and 11:30h, when the animals were grazing. Physiological and meteorological data were recorded in the last three days of June, July, August and September at 05:00h and at 16:00h. In the semi-intensive breeding system, the animals from different genetic groups were similar in both field behavior and physiological response patterns. Although the purebred goats had longer hair, they did not show symptoms of thermal discomfort. Their white hair helped to reflect the short wavelength rays and thus eliminate those at the longer wave lengths. We concluded that the animals raised in the semi-intensive milk production system in this study seem to have adapted to the climatic conditions of the semi-arid region of Rio Grande do Norte, Brazil

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Mate choice is a component of sexual selection. Trying to understand the patterns of this process, several studies have emphasized the adaptive value of sexual differences and their influence on the assessment of the market value. The pattern for adults presented on the scientific literature, which is based on the preference for certain characteristics, shows that men search a partner who shows high value of fecundity and fertility, thus looking for partners with the ability of being pregnant and nursing their offspring. On the other hand, women look for partners with high socioeconomic status, which is strongly associated with the ability to protect and provide resources for them and their offspring. Surprisingly, there is few works that investigated the mate choice patterns during the beginning of the period of sexual differentiation on the morphological, physiological and behavioral traits. The aim of this study was to investigate mate choice patterns in adolescence in order to describe their preferences and contribute to the understanding of human reproductive behavior. Took part of this research 1,232 students from educational institutions of Natal, Brazil, and visitors to the Scientific, Technological and Cultural Fair UFRN. In the Experimental Study 1, we applied a questionnaire to evaluate the importance of certain characteristics, assessed the degree of romantic involvement and real and ideal partners age preference. In the Experimental Study 2, we did a survey of characteristics considered relevant and evaluate the importance of these characteristics in mate choice. The Experimental Study 3 brought an investigation of mate choice patterns based on self-assessment of adolescents, evaluating ideal partner for a short-term and long-term relationships and actual partner. We found that adolescents are motivated to live romantic experiences. We also observed a preference for partners of similar age to that described for adults. Finally, we found similarities and differences in the preferences for characteristics in real and ideal partners in relation to the adult pattern. In addition, we observed high similarity on the self-assessment and assessment of real and ideal partners. We suggest that in the mate choice, adolescents are similar to young adults in some aspects but not all. Our results show the relevance of the reproductive behavior investigation in this human developmental period and reinforce that further studies should contribute to the understanding of human behavior in terms of ontogenetic development and their evolutionary history.

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Regarding the growing number of human beings with physical and mental pathologies associated to different stressor agents, attempts are being made to validate animal models with a close phylogenetic resemblance to man, to study stress response. Callithrix jacchus has been widely used in biomedical research, including on stress, but there is scarce information in the literature about how individual and social factors modulate stressor response in this species. This study uses 4 approaches to investigate the response of male and female adult C. jacchus, under situations of stress, and in the first we show evidence of the importance of this animal as an experimental model in research involving the hypothalamus-pituitary-adrenal axis. And we investigate if sex and baseline cortisol levels modulate the behavioral and hormonal response to separation. In two additional approaches investigate if type of social support (co-specific parent or non-parent) and social rank interfere in behavioral and hormonal when the animal are exposure to a new environment, paired with a co-specific (F2), exposure of the animal to a new environment, isolated (F3) or during reunion (F4). Finally, we also investigated the androgen levels in the males, with a focus on the challenge hypothesis, referring to environmental responsiveness and male-male exposure to relatives and non-relatives of C. jacchus. It was observed that: (1) the baseline cortisol of the animal is predictive of cortisol reactivity at separation; (2) males and females do not show dimorphism in the response of cortisol to stressors, although the females have higher baseline levels of this hormone and exhibit higher frequencies of anxiety-related behaviors; (3) only social support provided by relatives proved to be effective in buffering the cortisol response. In behavioral terms this response was dimorphic, showing that only the male dyads displayed an attenuated response to stress; (4) the males showed differences in cortisol levels as a function of social rank and study phases, whereas in the females no such alterations were observed. The males with indefinite dominance hierarchy (IDH) had reduced cortisol in F2 and F4, while the IDH females showed an increase in F3 and F4; (5) the males of relative and non-relative dyads did not exhibit variations in androgen levels as a function of a new environment. These results, taken together, (a) corroborate the use of C. jacchus as a good animal model for stress-related studies, given that they exhibit similar behavioral and physiological alterations to those of human beings in response to stressor agents; (b) point to the importance of considering individual and social modulating factors during experiments with stressors; (c) provide more reliable comparison parameters in studies where these primates are used as animal models, and (d) show that androgens vary as a function of genetic proximity (relative or non-relative) when the animals are faced with physical and social environmental challenges, thus providing important information for studying the challenge hypothesis in this species

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In this thesis we tested evolutionary hypotheses, with empirically collected data, in a sample composed of pregnant Brazilian women. We consider that during pregnancy and soon after the baby's birth fundamental reproductive decisions take place, given the complete feminine involvement with the reproduction phenomenon. The results are presented in four empirical articles related to the history of female reproduction. The topics approached were mate selection, the life-history theory, the strategies of parental investment and postpartum depression. Data collection was accomplished through interviews with pregnant women and after the baby s birth, with a sample composed of women from two income classes (low income and middle class), in Natal, Brazil. With respect to mate selection, the results suggest that a real situation of reproductive mate selection shows significant differences when compared to the results obtained in studies involving potential mate selection (Article I). Considering the life-history theory, we have partially confirmed the hypothesis of the father`s absence influencing the development of the young female syndrome (Article II). In regard to parental investment strategies and the decrease of fatherhood uncertainty, we identified a larger attribution of the baby's resemblance after birth with the father, confirming our hypothesis (Article III). The results related to postpartum depression occurrence partially support the hypothesis that it is an evolutionary adaptation (Article IV). This thesis is part of a consolidation movement of Evolutionary Psychology in Brazil and it presents results on female reproductive history hitherto unpublished.

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Parental care in mammals is influenced by somatosensory stimuli from infants, such as vocalization and sight and by changes in the hormone levels of caretakers. The aim of this study was to evaluate the behavioral and hormonal responses of twelve non reproductive adult male common marmosets (Callithrix jacchus) to infant cues, vocalization recordings, sight and physical contact with newborn. Six out of twelve males had previous experience in caretaking. In article 1, adult males were exposed to newborn vocalizations for 10 minutes. On control condition no sound was presented. In article 2, males were tested on two conditions: a) Control: an empty acrylic transparent box (test box) was placed in male s cage for 15 minutes, and b) Experimental: males were exposed to newborns into a closed text box for 15 minutes. The cage was kept closed to prevented from tactile, smell and acoustic stimulation by the infant on common marmoset males. In article 3, males were exposed to an open or closed text box, which allowed or not their access to and social interaction with the infants. After each observation sessions, blood samples were collected to evaluate the cortisol levels of males. In all studies, behavioral response of adult males was significantly modified by newborns sight, vocalization and physical contact. Males approached and spent more time near the sound source and showed an increase in locomotion during sound exposure. Furthermore, males approached, smelled and spent more time near the test box when the newborn was inside it. There was no difference in behavioral pattern between experienced and non-experienced males in articles 1 and 2. In article 3, behavioral pattern of males was influence by previous caretaking experience. Experienced males recovered quicker and carried the infants more than the inexperienced ones. However, inexperienced males showed a decrease in recovery latency and an increase in carrying time after successive exposure to infants. Cortisol levels changed after exposure to infant s vocalization, especially for experienced adult males. Male hormonal profile was not affected by the sight of infants neither by their previous experienced in caretaking. The occurrence of social interaction between the caretaker and infant did not modify the hormonal profile of common marmoset males; however, as much as experienced males carried the infants their cortisol levels decreased. Thus, members of a social group or potential caretakers common marmosets exposed to sensory cues from dependent infant such as vocalization, sight, smell and physical contact, changed their behavioral and hormonal responses that are physiological modulators of parental behavior in common marmoset

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The use of animal models in biomedical research is ever increasing. Models that use primates might also have advantages in terms of low maintenance costs and availability of biological knowledge, thereby favoring their use in different experimental protocols. Many current stress studies use animal models at different developmental stages since biological response differs during ontogeny. The aims of this study were to perform a detailed characterization of the developmental stages of common marmosets (Callithrix jacchus), a very important animal model used in biomedical research. Ten subjects, 6 females and 4 males, were followed from birth to initial adult age (16 months). Behavioral and fecal collection for measurement of adrenal (cortisol) and sex (progesterone, estradiol and androgens) hormones took place twice a week during the first month of life and once a week for the remainder of the study. Behavior was observed for 30 minutes in the morning (0700-09:00h) and afternoon (12:00-14:00h). Behavioral profile showed changes during ontogeny, characterizing the 4 developmental stages and the respective phases proposed by Leão et al (2009).. Differentiation of developmental stages was considered using the onset, end, change and stabilization of the behavioral profile parental care (weaning and carrying), ingestion (solid food), affiliation (social grooming) and autogrooming, agonism (scent marking and piloerection) and play behavior and endocrine profile. Infant weaning and carrying terminated within the infantile stage and the peak of solid food ingestion was recorded in the infantile III phase. Receiving grooming was recorded earlier than grooming performed by the infant and autogrooming. The first episode of scent marking was recorded in the 4th week and it was the least variable behavior, in terms of its onset, which, in almost all animals, was between the 5th and 7th week of life. Solitary play and play with the twin started around the 7th week and play with other members of the group started 8 weeks later. Sex hormone secretion started to differ from basal levels between the 21st and 23rd week of life, in males and females, suggesting that puberty occurs simultaneously in both sexes. Basal cortisol, even at an early age, was higher in females than in males. However, cortisol was not correlated with the juvenile stage, as expected, since this stage corresponds to the transition between infancy and adult age and most behaviors are intensified by this time. The behavioral and endocrine profile of subadult animals did not differ from that of the adults. These results provide more detailed parameters for the developmental process of C. jacchus and open new perspectives for the use of experimental approaches focused on the intermediate ontogenetic phases of this species

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Men and women express different preferences for ideal romantic partners. These preferences seem to vary with the level of involvement and commitment expected for the relationship and the perceptions people have about themselves. The current work was developed to expand the findings related to this subject, investigating the market perception of romantic relationships and the effect of context on self-assessment and preferences for romantic partners. For this purpose, 753 undergraduate, Brazilian and American, were enrolled between March 2010 and November 2012 and took part in at least one of the four studies that compose this research, performing the assessment of specific stimulus-subject descriptions. Studies one and two addressed Brazilian and American samples to respectively describe female and male expectations on human mating market. It was observed that individuals from both the genders expect positive assortative mating within couples, that each trait is not evaluated independently, and, in addition to biological predispositions, factors as environmental local constrains and cultural values may also affect mating expectations. The contrasts between the samples showed that Americans valued physical-attractiveness and social-status in describing the same-gender subjects and their expected partners, while Brazilians valued social-skills. Another expectation was also identified for both genders: physically attractive women and men of high-status were expected to be paired to each other. Study three addressed males and females expectations regarding which characteristics are most relevant in ensuring desirable partnerships for same-gender individuals. The results showed that men and women can be grouped together by having similar expectations. However, the group mainly composed of men considered status characteristics as the most important attributes, while the groups mostly composed of women indicated that social skills or physical characteristics as the most important in appealing to a desirable partner. Finally, study four investigated the effect of social comparison on self-perception and mate preferences, revealing that individuals were aware of the attributes valued by the opposite-gender and that self-perception was affected by the attributes of other people. In sum, this work evidenced that romantic relationships can be interpreted as a biological market and that the value of the attributes in the romantic mating marketplace are associated with reproductive relevance of the characteristics.

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Fibromyalgia (FM) is a non-inflammatory rheumatic syndrome of unknown etiology, with symptoms of diffuse musculoskeletal pain and presence of specific anatomic sites called tender points. The symptoms are often associated with fatigue, sleep disturbances, morning stiffness, alterations in pain perception, anxiety and depression. Fibromyalgia exhibits a correlation between physical and behavioral symptoms, which have a negative influence on the quality of life of patients. Emotional skills are important factors since they are related to subjective well-being, personal productivity, social interaction and interpersonal relationships. We aim to describe the physical and psychosocial interactions in women with FM, showing the association between perceived social support and affect with symptoms of pain, functionality and mood. We will also describe a body representation of pain in women with FM. Data were collected over 3 years and the sample size ranged between studies. This is an exploratory cross-sectional study conducted with a convenience sample of 63 women with FM and 42 healthy women as a control group (CT), aged 20-76 years, recruited through spontaneous demand at Onofre Lopes University Hospital (HUOL) and the Clinical School of Physiotherapy of Universidade Potiguar (UNP). The Fibromyalgia Impact Questionnaire (FIQ), Beck Depression Inventory (BDI), Social Support Scale (MOS), Hamilton Anxiety Scale and Scale of Positive and Negative Affect Schedule (PANAS), in addition to pressure algometry were used. For data analysis, we used parametric and non-parametric tests and a general linear model with adjustment variables and analysis of variance. A significant difference was found between pain threshold and tolerance, functionality, depression, anxiety, social support, and positive and negative affect between the groups. Affective states and social support were associated with anxiety, depression and functionality. A body was drawn representing pain with higher incidences in trapeze, supraspinatus and second ribs. The reason for studying sensory aspects, affective behavior and social support in FM patients opens perspectives for scientific and clinical research of this syndrome. Women with chronic pain such as FM appear to have altered mood states, less social support and affective dysfunctions, influencing the other symptoms of the syndrome

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The use and the demand for substances that enhance masculinity, strength and sexual power are not novel. Over the years, this search has assisted the research directions in this area, leading to the discovery of the primary male sex hormone testosterone in 1935. Since then, numerous testosterone analogue compounds were synthesized, which are generically called Anabolic Androgenic Steroids (AAS). The AAS were produced for therapeutic purposes, but an increase in the use of these compounds for other purposes occurred over time. Initially they were used mainly to improve performance in athletes. However, recent studies have shown that the use of AAS by non-athletes with aesthetical purposes have been increasing as well. The abuse of AAS with non-clinical purposes can promote a number of physiological alterations, such as heart, liver, respiratory and psychological problems such as changes in mood, levels of anxiety and aggression. Exposure to supraphysiological doses of AAS is associated with behavioral changes, however, little is known about the effects of AAS on cognitive functions. In this work, we aimed to mimic the AAS abuse in humans with intramuscular administration of a supraphysiological dose of testosterone propionate (TP) in rats. We investigated the effects of this treatment on different aspects of cognitive function, specifically learning, memory and anxiety. Adult male Wistar rats were tested in the spontaneous alternation, novel object recognition and plus-maze discriminative avoidance tasks. The control group received intramuscular injections of vegetable oil (vehicle), and the TP group received injections of TP (10 mg/kg, i.m.). The injections were administered for 40 days, with intervals of 48 hours (chronic treatment) or in a single injection (acute treatment). In addition to the behavioral assessments, we performed biochemical analyzes as indicators of the endocrine effects of the treatment. Our results show that chronic treatment with a supraphysiological dose of TP caused memory impairments in the novel object recognition and the discriminative avoidance tasks. The spatial working memory (evaluated by spontaneous alternation task) was not affected. Also, we did not observe changes in anxiety levels. Regarding the biochemical parameters, chronic treatment increased serum levels of glutamicpyruvic transaminase, an indicator of hepatic and pancreatic lesions (as those observed after chronic use of these substances in humans). On the other hand, acute treatment with PT did not promote significant changes in any of these parameters when compared to the control group. In summary, we conclude that chronic treatment with a supraphysiological dose of testosterone propionate produces memory deficits in novel object recognition and retrieval of the discriminative avoidance task in adult male rats

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Why are we attracted to some people but not to other ones? How is this attraction established? Which signs are characteristic of a good partner? These and many other questions concerning how mate attraction and mate selection work out among humans have been intriguing behavioral scientists. It is well-known that beauty indicates something about a potential mate s health. The odor may indicate a similar assessment, if we can assess how pheromones are integrated into human sexual behavior. However, what is the relation between age preference and body scent evaluation? In order to investigate this question, this study´s objective was identifying evidences which show that olfactory cues might reveal the potential mate s age and that it coincides with the ideal mate s profile. To produce the stimuli, men and women had to wear cotton t-shirts for three nights in order to have their body odor impregnated. After that, opposite-sex individuals evaluated the intensity and attractivity of these odor impregnated tshirts according to two Likert scales (4 points scale for intensity; 7 points scale for attractivity). We found differences between men and women on body scent perception, that indicates a better scent discrimination for women when it concerns the perception of potential mate s age. Another finding was the negative correlation between intensity and attractiveness perception for both sexes. We also verified that mate selection strategies are plural, more than one tactic simultaneously fitting in the same strategy, but all of them are related to differential investment of each sex on their own reproductive success