998 resultados para Diferències entre sexes -- Congressos
Resumo:
Offspring sex ratios were examined at the population and family level in the sexually monomorphic, socially monogamous fairy martin Petrochelidon ariel at five colony sites over a 4-year period (1993 1996). The sex of 465 nestlings from 169 broods % as determined using sex-specific PCR at the CHD locus. In accordance with predicted sex allocation patterns, population sex ratios at hatching and fledging did not differ from parity in an), year and the variance in brood sex ratios did not deviate from the binomial distribution, Further, brood sex ratio did not vary with hatching date during the season, brood number, brood size or colony size, The sex ratio or broods with extra-pair young did not differ from those without, while the sex ratio of broods fathered by males that gained extra-pair fertilizations did not differ from broods fathered by other males. Extra-pair chicks were as likely to be male as female. Neither the total number of feeding visits to the brood nor the relative feeding contribution by the sexes varied significantly with brood sex ratio. Brood sex ratios were also unrelated to paternal size, condition and breeding experience or maternal condition and breeding experience, However, contrary to our prediction, brood sex ratio was negatively correlated with maternal size. Generally, these results were consistent with our expectations that brood sex ratios would not vary with environmental factors or parental characteristics, and would not influence the level of parental provisioning. However, the finding that females with longer tarsi produced an excess of daughters is difficult to reconcile with our current understanding or fairy martin life history and breeding ecology.
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Although largely solitary, humpback whales exhibit a number of behaviours where individuals co-operate with one another, for example during bubble net feeding. Such cases could be due to reciprocal altruism brought on by exceptional circumstances, for example the presence of abundant shoaling fish. An alternative explanation is that these behaviours have evolved through kin selection. With little restriction to either communication or movement, diffuse groups of relatives could maintain some form of social organization without the need to travel in tight-nit units. To try to distinguish between these hypotheses, we took advantage of the fact that migrating humpback whales often swim together in small groups. If kin selection is important in humpback whale biology, these groups should be enriched for relatives. Consequently, we analysed biopsy samples from 57 groups of humpback whales migrating off Eastern Australia in 1992. A total of 142 whales were screened for eight microsatellite markers. Mitochondrial DNA sequences (371 bp) were also used to verify and assist kinship identification. Our data add support to the notion that mothers travel with their offspring for the first year of the calf's life. However, beyond the presence of mother-calf/yearling pairs, no obvious relatedness pattern was found among whales sampled either in the same pod or on the same day. Levels of relatedness did not vary between migratory phases (towards or away from the breeding ground), nor between the two sexes considered either overall or in the north or south migrations separately. These findings suggest that, if any social organization does exist, it is formed transiently when needed rather than being a constant feature of the population, and hence is more likely based on reciprocal altruism than kin selection.
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Granulomatous meningoencephalomyelitis (GME) is a morphological description of an inflammatory disorder of the canine central nervous system (CNS). It has been reported in many areas of the world. including Australia, and is one of the more common nervous disorders of dogs. Most breeds of dogs of both sexes and all ages can be affected but young to middle-aged small and terrier breeds have been stated as being more susceptible. There are variable anatomical forms and distribution of the lesions in the CNS; the presenting clinical signs can reflect singly or collectively cerebellar, cerebral, and brain stem dysfunction. Meningeal and spinal cord involvement are also common. There is no specific diagnostic test but a combination of clinical signs, history and cerebro-spinal fluid cytology are useful indicators. However differential diagnosis from other inflammatory disorders of the brain is difficult. No infectious agent aetiology has been established for GME and therefore no satisfactory therapeutic approach is available. The role of the immune system in terms of either initiating or potentiating the lesions in the CNS appears to be the most likely direction for further investigation into the nature of this disorder.
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We determined which factors predict the presence and abundance of Dusky Moorhens (Gallinula tenebrosa) at wetlands by surveying the ecological and habitat characteristics of 62 sites across south-east Queensland. Moorhens were observed in 48 of the sites sampled. They were more likely to be found at sites surrounded by taller terrestrial vegetation and where free-floating and attached aquatic vegetation was more abundant. The number of moorhens found at a site increased in relation to vegetation height, the abundance of attached aquatic vegetation and the number of purple swamphens observed. These results suggest that there are ecological constraints on the distribution of moorhens, and that food abundance and the availability of suitable nesting sites determine the overall distribution and abundance of moorhens in wetlands. Adult moorhens develop brightly coloured fleshy frontal shields, bills and legs when breeding, although in some populations birds maintain year-round colouration. We observed year-round breeding colouration in 23 out of 34 sampling sites that had moorhens and were surveyed in August. Coloured moorhens were found during winter at sites with higher minimum winter temperatures, and more abundant free-floating and submerged leafy vegetation. In addition, higher proportions of moorhens were coloured at sites with higher mean minimum temperatures. The retention of year-round breeding colouration appears to be restricted to areas with warmer winter temperatures and more abundant food. The results suggest that areas not occupied by moorhens are of inadequate quality to support breeding populations. We suggest that ecological constraints on independent breeding in Dusky Moorhens may have favoured the evolution of their unusual cooperative breeding system, which involves frequent mate-sharing by both sexes.
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Migraine is a common neurovascular brain disorder that is manifested in recurrent episodes of disabling headache. The aim of the present study was to compare the prevalence and heritability of migraine across six of the countries that participate in GenomEutwin project including a total number of 29,717 twin pairs. Migraine was assessed by questionnaires that differed between most countries. It was most prevalent in Danish and Dutch females (32% and 34%, respectively), whereas the lowest prevalence was found in the younger and older Finnish cohorts (13% and 10%, respectively). The estimated genetic variance (heritability) was significant and the same between sexes in all countries. Heritability ranged from 34% to 57%, with lowest estimates in Australia, and highest estimates in the older cohort of Finland, the Netherlands, and Denmark. There was some indication that part of the genetic variance was non-additive, but this was significant in Sweden only. In addition to genetic factors, environmental effects that are non-shared between members of a twin pair contributed to the liability of migraine. After migraine definitions are homogenized among the participating countries, the GenomEUtwin project will provide a powerful resource to identify the genes involved in migraine.
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Body mass index (BMI), a simple anthropometric measure, is the most frequently used measure of adiposity and has been instrumental in documenting the worldwide increase in the prevalence of obesity witnessed during the last decades. Although this increase in overweight and obesity is thought to be mainly due to environmental changes, i.e., sedentary lifestyles and high caloric diets, consistent evidence from twin studies demonstrates high heritability and the importance of genetic differences for normal variation in BMI. We analysed self-reported data on BMI from approximately 37,000 complete twin pairs (including opposite sex pairs) aged 20-29 and 30-39 from eight different twin registries participating in the GenomEUtwin project. Quantitative genetic analyses were conducted and sex differences were explored. Variation in BMI was greater for women than for men, and in both sexes was primarily explained by additive genetic variance in all countries. Sex differences in the variance components were consistently significant. Results from analyses of opposite sex pairs also showed evidence of sex-specific genetic effects suggesting there may be some differences between men and women in the genetic factors that influence variation in BMI. These results encourage the continued search for genes of importance to the body composition and the development of obesity. Furthermore, they suggest that strategies to identify predisposing genes may benefit from taking into account potential sex specific effects.
Resumo:
A major component of variation in body height is due to genetic differences, but environmental factors have a substantial contributory effect. In this study we aimed to analyse whether the genetic architecture of body height varies between affluent western societies. We analysed twin data from eight countries comprising 30,111 complete twin pairs by using the univariate genetic model of the Mx statistical package. Body height and zygosity were self-reported in seven populations and measured directly in one population. We found that there was substantial variation in mean body height between countries; body height was least in Italy (177 cm in men and 163 cm in women) and greatest in the Netherlands (184 cm and 171 cm, respectively). In men there was no corresponding variation in heritability of body height, heritability estimates ranging from 0.87 to 0.93 in populations under an additive genes/unique environment (AE) model. Among women the heritability estimates were generally lower than among men with greater variation between countries, ranging from 0.68 to 0.84 when an additive genes/shared environment/unique environment (ACE) model was used. In four populations where an AE model fit equally well or better, heritability ranged from 0.89 to 0.93. This difference between the sexes was mainly due to the effect of the shared environmental component of variance, which appears to be more important among women than among men in our study populations. Our results indicate that, in general, there are only minor differences in the genetic architecture of height between affluent Caucasian populations, especially among men.
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The evolution of sexual dimorphism may occur when natural and sexual selection result in different optimum trait values for males and females. Perhaps the most prominent examples of sexual dimorphism occur in sexually selected traits, for which males usually display exaggerated trait levels, while females may show reduced expression of the trait. In some species, females also exhibit secondary sexual traits that may either be a consequence of a correlated response to sexual selection on males or direct sexual selection for female secondary sexual traits. In this experiment, we simultaneously measure the intersex genetic correlations and the relative strength of sexual selection on males and females for a set of cuticular hydrocarbons in Drosophila serrata. There was significant directional sexual selection on both male and female cuticular hydrocarbons: the strength of sexual selection did not differ among the sexes but males and females preferred different cuticular hydrocarbons. In contrast with many previous studies of sexual dimorphism, intersex genetic correlations were low. The evolution of sexual dimorphism in D. serrata appears to have been achieved by sex-limited expression of traits controlled by genes on the X chromosome and is likely to be in its final stages.
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The mite family Stigmaeidae (Acari:Prostigmata) is of considerable importance in biological control, but its genera are often poorly defined and have never been subjected to cladistic analysis. Herein, we report the stigmaeid genus Ledermuelleriopsis Willmann from Australia for the first time, present a preliminary phylogenetic analysis that demonstrates that Eustigmaeus Berlese and Ledermuelleriopsis Willman are distinct, review the genus at the world level, and provide diagnostic characters of the adult females for each of the 21 known species. We also catalogue habitats, distributions and localities of holotypes. Four new species from Australia are described and illustrated: L. parvilla, sp. nov. from old dune sand, L. barbellata, sp. nov. from wet-sandy heath litter, and L. pustulosa, sp. nov. and L. claviseta, sp. nov. from dry eucalypt forest litter. A key to adult females of all known Ledermuelleriopsis species is provided. The Australian species and L. incisa Wood from New Zealand can be separated from all other members of the genus by a synapomorphy: the reduction of the number of setae on the aggenital shield to one pair. Results of a preliminary morphological cladistic analysis for those stigmaeid genera in which the larvae and adults of both sexes are known, indicate that Ledermuelleriopsis is basal to a clade containing Cheylostigmaeus Willman and Eustigmaeus.
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Objective: To measure the prevalence of obesity in Australian adults and to examine the associations of obesity with socioeconomic and lifestyle factors. Design: AusDiab, a cross-sectional study conducted between May 1999 and December 2000, involved participants from 42 randomly selected districts throughout Australia. Participants: Of 20 347 eligible people aged greater than or equal to 25 years who completed a household interview, 11247 attended the physical examination at local survey sites (response rate, 55%). Main outcome measures: Overweight and obesity defined by body mass index (BMI; kg/m(2)) and waist circumference (cm); sociodemographic factors (including smoking, physical activity and television viewing time). Results: The prevalence of overweight and obesity (BMI greater than or equal to 25.0 kg/m(2); waist circumference greater than or equal to 80.0 cm [women] or greater than or equal to 94.0 cm [men]) in both sexes was almost 60%, defined by either BMI or waist circumference. The prevalence of obesity was 2.5 times higher than in 1980. Using waist circumference, the prevalence of obesity was higher in women than men (34.1% v 26.8%; P < 0.01). Lower educational status, higher television viewing time and lower physical activity time were each strongly associated with obesity, with television viewing time showing a stronger relationship than physical activity time. Conclusions: The prevalence of obesity in Australia has more than doubled in the past 20 years. Strong positive associations between obesity and each of television viewing time and lower physical activity time confirm the influence of sedentary lifestyles on obesity, and underline the potential benefits of reducing sedentary behaviour, as well as increasing physical activity, to curb the obesity epidemic.
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Este artigo apresenta a evolu????o de reflex??es sobre o papel da Rede Nacional de Escolas de Governo no Brasil, em sequ??ncia a trabalhos apresentados em congressos anteriores do CLAD (Carvalho, 2005, 2009). O contexto brasileiro, nos aspectos que mais afetam os desafios postos aos processos de capacita????o profissional de servidores p??blicos, ?? inicialmente apresentado, para facilitar a apreens??o das experi??ncias que ser??o analisadas. Em seguida, ?? feita a caracteriza????o da Rede Nacional, apontando-se alguns de seus resultados. Outras experi??ncias de Rede, em geral atuando como ???sub-redes??? da Rede Nacional s??o descritas: relata-se a situa????o da articula????o das escolas de governo no ??mbito do Poder Executivo Federal, o chamado ???Sistema de Escolas de Governo da Uni??o???; em seguida s??o apresentadas tr??s experi??ncias existentes no n??vel subnacional, de redes em funcionamento em tr??s dos estados brasileiros, tratando dos casos da ???Rede Estadual de Escolas de Governo do Paran?????, do projeto em implanta????o denominado ???Rede Escola de Governo do Estado do Rio Grande do Sul???, e da ???Rede Estadual de Escolas de Governo do Cear?????. Em seguida, faz-se o relato da articula????o em rede das escolas vinculadas aos tribunais de contas, a ???Rede de Educa????o Corporativa dos Tribunais de Contas???. Ao final, s??o constru??das reflex??es sobre o que essas distintas experi??ncias de redes de capacita????o apontam de espec??fico, com vista a contribuir para o debate sobre as diversas op????es pol??tico-organizativas que podem ser implementadas para o aumento da sinergia e capacidade de atua????o das entidades formadoras, com vista ?? melhoria da qualidade do servi??o p??blico brasileiro, por meio do investimento na educa????o e qualifica????o profissional dos agentes p??blicos
Resumo:
Ao longo da ??ltima d??cada, o CPP-II enfrentou os mesmos problemas que atingiram a sa??de p??blica em todo o pa??s, agravados pelo fato de lidar com a sa??de mental, ??rea normalmente relegada a segundo plano em termos de investimentos. Em 1988, servidores comprometidos com a consecu????o de um servi??o p??blico eficiente e de boa qualidade, idealizaram um sistema de realiza????o de congressos internos no CPP-II ???com a participa????o de funcion??rios, usu??rios e a comunidade em geral ??? visando formular normas, procedimentos e pol??ticas duradouras para a institui????o. A iniciativa alcan??ou maior participa????o institucional mediante ampla discuss??o das propostas, descentraliza????o e horizontaliza????o das decis??es, maior envolvimento dos usu??rios e da comunidade em geral, estabelecimento de pol??ticas mais duradouras, geridas conjuntamente por servidores, usu??rios e comunidade, melhor qualidade da assist??ncia prestada e alian??a com os usu??rios para a obten????o de recursos para a institui????o e sua adequada destina????o e utiliza????o
Resumo:
A integração de tecnologias de informação e comunicação no contexto educacional tem sido tema de diversos congressos e simpósios ao redor do mundo e no Brasil. Neste sentido, vários estudos têm sido realizados com o objetivo de se obter metodologias que tornem efetivo o emprego das novas tecnologias no ensino. Este artigo mostra um estudo que investigou a interação entre estudantes universitários da área de ciências exatas e um ambiente de modelagem computacional qualitativo em atividades de modelagem expressiva. Os resultados obtidos mostram que os estudantes foram capazes de criar e modificar o modelo do sistema proposto a partir de suas próprias concepções.
Resumo:
José Plínio Baptista School of Cosmology (1. : 2012 : Anchieta, ES). Seminário realizado no período de 14 a 19 de outubro de 2012.
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Esta tese se propôs investigar a lógica inferencial das ações e suas significações em situações que mobilizam as noções de composição probabilística e acaso, bem como o papel dos modelos de significação no funcionamento cognitivo de adultos. Participaram 12 estudantes adultos jovens da classe popular, voluntários, de ambos os sexos, de um curso técnico integrado ao Ensino Médio da Educação de Jovens e Adultos. Foram realizados três encontros, individualmente, com registro em áudio e planilha eletrônica, utilizando-se dois jogos, o Likid Gaz e o Lucky Cassino, do software Missão Cognição (Haddad-Zubel, Pinkas & Pécaut, 2006), e o jogo Soma dos Dados (Silva, Rossetti & Cristo, 2012). Os procedimentos da tarefa foram adaptados de Silva e Frezza (2011): 1) apresentação do jogo; 2) execução do jogo; 3) entrevista semiestruturada; 4) aplicação de três situações-problema com intervenção segundo o Método Clínico; 5) nova partida do jogo; e 6) realização de outras duas situações-problema sem intervenção do Método Clínico. Elaboraram-se níveis de análise heurística, compreensão dos jogos e modelos de significação a partir da identificação de particularidades de procedimentos e significações nos jogos. O primeiro estudo examinou as implicações dos modelos de significação e representações prévias no pensamento do adulto, considerando que o sujeito organiza suas representações ou esquemas prévios relativos a um objeto na forma de modelos de significação em função do grau de complexidade e novidade da tarefa e de sua estrutura lógico matemática, que evoluem por meio do processo de equilibração; para o que precisa da demanda a significar esse aspecto da 13 realidade. O segundo estudo investigou a noção de combinação deduzível evidenciada no jogo Likid Gaz, identificando o papel dos modelos de significação na escolha dos procedimentos, implicando na rejeição de condutas de sistematização ou enumeração. Houve predominância dos níveis iniciais de análise heurística do jogo. O terceiro estudo examinou a noção de probabilidade observada no jogo Lucky Cassino, no qual a maioria dos participantes teve um nível de compreensão do jogo intermediário, com maior diversidade de modelos de significação em relação aos outros jogos, embora com predominância dos mais elementares. A síntese das noções de combinação, probabilidade e acaso foi explorada no quarto estudo pelo jogo Soma dos Dados (Silva, Rossetti & Cristo, 2012), identificando-se que uma limitação para adequada compreensão das ligações imbricadas nessas noções é a implicação significante – se aleatório A, então indeterminado D (notação A D), com construção de pseudonecessidades e pseudo-obrigações ou mesmo necessidades locais, generalizadas inapropriadamente. A resistência ou obstáculos do objeto deveria provocar perturbações, mas a estrutura cognitiva, o ambiente social e os modelos culturais, e a afetividade podem interferir nesse processo.