a b s t r a c tWe investigated the seasonal patterns of Amazonian forest photosynthetic activity, and the effects thereon of variations in climate and land-use, by integrating data from a network of ground-based eddy flux towers in Brazil established as part of the 'Large-Scale Biosphere Atmosphere Experiment in Amazonia' project. We found that degree of water limitation, as indicated by the seasonality of the ratio of sensible to latent heat flux (Bowen ratio) predicts seasonal patterns of photosynthesis. In equatorial Amazonian forests (5• N-5 • S), water limitation is absent, and photosynthetic fluxes (or gross ecosystem productivity, GEP) exhibit high or increasing levels of photosynthetic activity as the dry season progresses, likely a consequence of allocation to growth of new leaves. In contrast, forests along the southern flank of the Amazon, pastures converted from forest, and mixed forest-grass savanna, exhibit dry-season declines in GEP, consistent with increasing degrees of water limitation. Although previous work showed tropical ecosystem evapotranspiration (ET) is driven by incoming radiation, GEP observations reported here surprisingly show no or negative relationships with photosynthetically active radiation (PAR). Instead, GEP fluxes largely followed the phenology of canopy photosynthetic capacity (Pc), with only deviations from this primary pattern driven by variations in PAR. Estimates of leaf flush at three * Corresponding author. Tel.: +1 520 6261500; fax: +1 520 621 9190. 182-183 (2013) 128-144 129 non-water limited equatorial forest sites peak in the dry season, in correlation with high dry season light levels. The higher photosynthetic capacity that follows persists into the wet season, driving high GEP that is out of phase with sunlight, explaining the negative observed relationship with sunlight. Overall, these patterns suggest that at sites where water is not limiting, light interacts with adaptive mechanisms to determine photosynthetic capacity indirectly through leaf flush and litterfall seasonality. These mechanisms are poorly represented in ecosystem models, and represent an important challenge to efforts to predict tropical forest responses to climatic variations.
[1] We investigated the seasonal patterns of water vapor and sensible heat flux along a tropical biome gradient from forest to savanna. We analyzed data from a network of flux towers in Brazil that were operated within the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA). These tower sites included tropical humid and semideciduous forest, transitional forest, floodplain (with physiognomies of cerrado), and cerrado sensu stricto. The mean annual sensible heat flux at all sites ranged from 20 to 38 Wm À2, and was generally reduced in the wet season and increased in the late dry season, coincident with seasonal variations of net radiation and soil moisture. The sites were easily divisible into two functional groups based on the seasonality of evaporation: tropical forest and savanna. At sites with an annual precipitation above 1900 mm and a dry season length less than 4 months (Manaus, Santarem and Rondonia), evaporation rates increased in the dry season, coincident with increased radiation. Evaporation rates were as high as 4.0 mm d À1 in these evergreen or semidecidous forests. In contrast, ecosystems with precipitation less than 1700 mm and a longer dry season (Mato Grosso, Tocantins and São Paulo) showed clear evidence of reduced evaporation in the dry season. Evaporation rates were as low as 2.5 mm d À1 in the transitional forests and 1 mm d À1 in the cerrado. The controls on evapotranspiration seasonality changed along the biome gradient, with evaporative demand (especially net radiation) playing a more important role in the wetter forests, and soil moisture playing a more important role in the drier savannah sites.
Sexual behavior may be altered during pregnancy. The authors aimed to investigate the behavior of pregnant women in terms of level of sexual initiative and change in sexual positions for intercourse. The authors conducted a retrospective research with 156 pregnant Brazilian women who completed a questionnaire. Before pregnancy, both partners usually initiated sex, whereas during pregnancy, the male partner generally did. In general, women who took the sexual initiative showed better scores in the sexuality variables. During pregnancy, the use of each sexual position reduced significantly. Couples in which both partners take the sexual initiative tend to accept a wider variety of sexual positions.
BackgroundThe International Index of Erectile Function has been proposed as a method for assessing sexual function assisting the diagnosis and classification of erectile dysfunction. However, IIEF was not validated for the Portuguese language. ObjectiveValidate the International Index of Erectile Function in patients with cardiopulmonary and metabolic diseases. MethodsThe sample consisted of 108 participants of to Cardiopulmonary and Metabolic program Rehabilitation (CPMR) in southern Brazil. The clarity assessment of the instrument was performed using a scale ranging from zero to 10. The construct validity was carried out by confirmatory factor analysis (KMO = 0.85; Barllet p < 0.001), internal consistency by Cronbach's alpha and reproducibility and interrater reliability via the test retest method. ResultsThe items were considered very clear with averages superior to 9. The internal consistency resulted in 0.89. The majority of items related correctly with their domains, with exception of three questions from sexual satisfaction domain, and one from erectile function. All items showed excellent stability of measure and substantial to almost perfect agreement. ConclusionThe present study showed that the IIEF is valid and reliable for use in participants of a cardiopulmonary and metabolic rehabilitation program.
Resumo O bullying escolar pode envolver crianças de diferentes maneiras, fazendo com que essas assumam papéis diferenciados. Dentre estes, têm-se vítimas, agressores e vítimas-agressoras. O objetivo deste estudo foi descrever como ocorre o bullying em escolas de alta vulnerabilidade social da Grande Florianópolis e os papéis assumidos pelos alunos nesse fenômeno. Quanto ao método, participaram 409 crianças e adolescentes do terceiro ao quinto ano e da quarta à sexta série do ensino fundamental, de duas escolas públicas municipais, com idades entre 8 e 16 anos (X=11,14). Como instrumento, utilizou-se o Questionário de Olweus adaptado à população brasileira. Para a análise dos dados, empregaram-se a estatística descritiva e estatística inferencial por meio dos testes Mann Whitney e Kruskal Wallis. Quanto aos resultados, 29,8% dos meninos e 40,5% das meninas relataram terem sido vítimas; já 32,3% dos meninos e 24,6% das meninas relataram terem sido agressores. As vítimas foram as que se mostraram mais dispostas a ajudar como podem um colega que esteja sofrendo agressão (X=1,54; p>0,001), mesmo que não o conheçam (X=1,57; p>0,004). Em contrapartida, os agressores se diferenciaram do grupo que não participa (X=1,73) e do grupo das vítimas (X=2,34), sendo aqueles que menos se sentiram sozinhos (X=1,47; p>0,001). Concluiu-se que as informações obtidas neste estudo são indispensáveis na busca de alternativas para redução do bullying escolar. O fortalecimento das relações entre escola e alunos, e um maior preparo dos professores e funcionários são extremamente necessários para tentar minimizar os efeitos dos fatores de risco a que essas crianças estão expostas e consequentemente a violência na escola.
This research used interview and questionnaire data from homosexual (n = 177), bisexual (n = 157), and heterosexual (n = 544) men between 20 and 30 years of age among lower class men and university students in three countries: Brazil, Thailand, and Turkey. The main goal of the study was to examine the recalled childhood sex-typed behavior and adult sports preferences that distinguish homosexuals from bisexuals and heterosexuals. In all three cultures and both social groups, homosexual men were almost always more likely as children to have wanted to be a girl, to cross-dress, to play with girls, to do girls' tasks, and to practice fewer sports. They were also less likely to bully others or to engage in physical fights. As children, homosexual men were more likely to prefer swimming and playing volleyball rather than soccer and, as adults, they preferred watching gymnastics and swimming over soccer. The bisexuals scored intermediate mostly in ''desire to be a girl'' and ''cross-dressing,'' although they were much closer to the heterosexuals. These results, coupled with previous crosscultural research, suggest that cross-gender behavior in childhood may characterize most male homosexuals regardless of their cultural milieu.
This study investigated whether homosexually identified males in a small Brazilian fishing community are similar to homosexually identified males described in the international literature. In addition, it attempted to distinguish heterosexuals who have sex with homosexuals from other heterosexuals. A total of 41 men were classified into three sexual categories: paneleiros ("pan cabinets"), who have sex only with men, and invariably so in a bottom position; persistent heterosexuals, who have sex only with women; and paneleiro lovers, who have sex with women and with paneleiros, but invariably in a top position. There were significant differences in childhood play activities, sexual inclinations, and sports preferences between paneleiros and non-paneleiros; however, paneleiro lovers and persistent heterosexuals were not significantly different with regard to these variables or with regard to access to women. These findings add to the cross-cultural literature on childhood cross-gender behavior and homoerotic activities among non-homosexually identified males.
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