MAPEAMENTO DO PALEOLEITO DO CANAL DO ALBARDÃO, BACIA DE PELOTAS - BRASIL

A plataforma continental do extremo-sul brasileiro contempla um extenso e profundo canal submerso, denominado Canal do Albardão. Esta feição foi apontado por Kowsmann et al. (1977) como um paleocanal parcialmente preenchido, e batimetricamente mapeada por por Campos et al. (2009). Neste trabalho é apresentada a estrutura geomorfológica de subsuperfície do mesmo, sugerindo suas possíveis relações com as áreas adjacentes

Next-generation sequencing analysis of the Tineola bisselliella larval gut transcriptome reveals candidate enzymes for keratin digestion

The clothes moth Tineola bisselliella is one of a few insects that can digest keratin, leading to the destruction of clothing, textiles and artwork. The mechanism of keratin digestion is not yet fully understood, partly reflecting the lack of publicly available genomic and transcriptomic data. Here we present a high-quality gut transcriptome of T. bisselliella generated from larvae reared on keratin-rich and keratin-free diets. The overall transcriptome consists of 428,221 contigs that were functionally annotated and screened for candidate enzymes involved in keratin utilization. As a mechanism for keratin digestion, we identified cysteine synthases, cystathionine β-synthases and cystathionine γ-lyases. These enzymes release hydrogen sulfite, which may reduce the disulfide bonds in keratin. The dataset also included 27 differentially expressed contigs with trypsin domains, among which 20 were associated with keratin feeding. Finally, we identified seven collagenases that were upregulated on the keratin-rich diet. In addition to this enzymatic repertoire potentially involved in breaking down keratin, our analysis of poly(A)-enriched and poly(A)-depleted transcripts suggested that T. bisselliella larvae possess an unstable intestinal microbiome that may nevertheless contribute to keratin digestion

The NASA Infrared Telescope Facility Comet Halley monitoring program 2: Post-perihelion results

The post perihelion results of a 1 to 20 micrometer infrared monitoring program of Comet Halley are presented. These results complement previous observations of the pre-perihelion passages of Halley. The observations cover the time period of Mar. 1986 to the present time. During the time the comet was observable, two or more observations were obtained per month. The most interesting results were: (1) a detectable change in the J-H and H-K colors of Halley, and (2) a search for a nucleus rotation at J during 20 Feb. to 10 Mar. was unsuccessful. The perihelion J-H and K-K colors were constant at 0.48 + or - 0.01 and 0.17, respectively. A preliminary reduction of the data is given. It is concluded that the colors were at first similar to pre-perihelion and then changed from July onward to be bluer and more similar to the solar colors. This suggests that a change may have occurred in the composition of the dust coma of Halley in July 1986

Social support and leisure-time physical activity: longitudinal evidence from the Brazilian Pró-Saúde cohort study

<p>Abstract</p> <p>Background</p> <p>Although social support has been observed to exert a beneficial influence on leisure-time physical activity (LTPA), multidimensional approaches examining social support and prospective evidence of its importance are scarce. The purpose of this study was to investigate how four dimensions of social support affect LTPA engagement, maintenance, type, and time spent by adults during a two-year follow-up.</p> <p>Methods</p> <p>This paper reports on a longitudinal study of 3,253 non-faculty public employees at a university in Rio de Janeiro (the Pró-Saúde study). LTPA was evaluated using a dichotomous question with a two-week reference period, and further questions concerning LTPA type (individual or group) and time spent on the activity. Social support was measured by the Medical Outcomes Study Social Support Scale (MOS-SSS). To assess the association between social support and LTPA, two different statistical models were used: binary and multinomial logistic regression models for dichotomous and polytomous outcomes, respectively. Models were adjusted separately for those who began LTPA in the middle of the follow up (engagement group) and for those who had maintained LTPA since the beginning of the follow up (maintenance group).</p> <p>Results</p> <p>After adjusting for confounders, statistically significant associations (p < 0.05) between dimensions of social support and group LTPA were found in the engagement group. Also, the emotional/information dimension was associated with time spent on LTPA (OR = 2.01; 95% CI 1.2-3.9). In the maintenance group, material support was associated with group LTPA (OR = 1.80; 95% CI; 1.1-3.1) and the positive social interaction dimension was associated with time spent on LTPA (OR = 1.65; 95% CI; 1.1-2.7).</p> <p>Conclusions</p> <p>All dimensions of social support influenced LTPA type or the time spent on the activity. However, our findings suggest that social support is more important in engagement than in maintenance. This finding is important, because it suggests that maintenance of LTPA must be associated with other factors beyond the individual's level of social support, such as a suitable environment and social/health policies directed towards the practice of LTPA.</p

Diferenças de gênero no apoio social e atividade física de lazer

OBJECTIVE To identify gender differences in social support dimensions’ effect on adults’ leisure-time physical activity maintenance, type, and time. METHODS Longitudinal study of 1,278 non-faculty public employees at a university in Rio de Janeiro, RJ, Southeastern Brazil. Physical activity was evaluated using a dichotomous question with a two-week reference period, and further questions concerning leisure-time physical activity type (individual or group) and time spent on the activity. Social support was measured with the Medical Outcomes Study Social Support Scale. For the analysis, logistic regression models were adjusted separately by gender. RESULTS A multinomial logistic regression showed an association between material support and individual activities among women (OR = 2.76; 95%CI 1.2;6.5). Affective support was associated with time spent on leisure-time physical activity only among men (OR = 1.80; 95%CI 1.1;3.2). CONCLUSIONS All dimensions of social support that were examined influenced either the type of, or the time spent on, leisure-time physical activity. In some social support dimensions, the associations detected varied by gender. Future studies should attempt to elucidate the mechanisms involved in these gender differences.OBJETIVO Identificar diferenças de gênero no efeito de dimensões de apoio social na manutenção, tipo e tempo da atividade física de lazer em adultos. MÉTODOS Estudo longitudinal com 1.278 funcionários públicos não docentes de uma universidade do Rio de Janeiro. A atividade física foi avaliada utilizando questão dicotômica, com um período de referência de duas semanas, e outras questões relativas ao tipo de atividade (individual ou grupo) e ao tempo gasto na atividade. O apoio social foi medido pelo Medical Outcomes Study Social Support Scale. Para a análise, os modelos de regressão logística foram ajustados separadamente por gênero. RESULTADOS A regressão logística multinomial mostrou associação entre o apoio material e as atividades individuais (OR = 2,76, IC95% 1,2;6,5) entre as mulheres. O apoio afetivo foi associado com o tempo gasto em atividades físicas de lazer (OR = 1,80, IC95% 1,1;3,2) apenas entre os homens. CONCLUSÕES Todas as dimensões de apoio social examinadas influenciaram o tipo ou o tempo gasto em atividades físicas de lazer. Em algumas dimensões de apoio social, as associações variaram segundo gênero. Estudos futuros devem elucidar os mecanismos envolvidos nessas diferenças entre os gêneros

Influência do regime hídrico na fenologia do arroz irrigado por sulco.

O objetivo deste trabalho foi caracterizar como o regime hídrico em três porções do talhão (superior, médio e inferior) afetou os principais estádios de desenvolvimento da planta visando subsidiar o planejamento das práticas

Advances in surface EMG signal simulation with analytical and numerical descriptions of the volume conductor

Surface electromyographic (EMG) signal modeling is important for signal interpretation, testing of processing algorithms, detection system design, and didactic purposes. Various surface EMG signal models have been proposed in the literature. In this study we focus on 1) the proposal of a method for modeling surface EMG signals by either analytical or numerical descriptions of the volume conductor for space-invariant systems, and 2) the development of advanced models of the volume conductor by numerical approaches, accurately describing not only the volume conductor geometry, as mainly done in the past, but also the conductivity tensor of the muscle tissue. For volume conductors that are space-invariant in the direction of source propagation, the surface potentials generated by any source can be computed by one-dimensional convolutions, once the volume conductor transfer function is derived (analytically or numerically). Conversely, more complex volume conductors require a complete numerical approach. In a numerical approach, the conductivity tensor of the muscle tissue should be matched with the fiber orientation. In some cases (e.g., multi-pinnate muscles) accurate description of the conductivity tensor may be very complex. A method for relating the conductivity tensor of the muscle tissue, to be used in a numerical approach, to the curve describing the muscle fibers is presented and applied to representatively investigate a bi-pinnate muscle with rectilinear and curvilinear fibers. The study thus propose an approach for surface EMG signal simulation in space invariant systems as well as new models of the volume conductor using numerical methods

Emissões de Gases de Efeito Estufa da Rotação de Soja e Arroz Irrigado em Terras Baixas do Rio Grande do Sul.

A introdução da soja em rotação com o arroz irrigado constitui alternativa promissora para elevar a sustentabilidade dos sistemas de produção em terras baixas. Além dos benefícios inerentes à diversificação de culturas, por diminuir o período de tempo em que o solo é mantido inundado para o cultivo de arroz, pode influenciar no potencial de emissão de gases de efeito estufa (GEE) do sistema de produção. Este trabalho foi realizado com o objetivo de avaliar as emissões de metano (CH4) e óxido nitroso (N2O) e o potencial de aquecimento global (PAGp) de conformações da rotação soja/arroz irrigado em terras baixas do Rio Grande do Sul. O estudo foi realizado nas safras agrícolas 2019/2020 a 2021/2022, em Planossolo, em Capão do Leão RS. Avaliaram-se as conformações 2:1 (soja/soja/arroz e arroz/arroz/soja) e 1:1 (soja/arroz/soja e arroz/soja/arroz) da rotação soja/arroz irrigado. Para comparar o efeito das rotações de culturas sobre as emissões de GEE, consideraram-se os dados da safra 2021/2022, que retratam um ciclo completo das conformações 2:1 e 1:1. Comparou-se, ainda, a totalização das emissões sazonais de CH4 e N2O e do PAGp das conformações de rotações ao longo das três safras agrícolas. A rotação com soja reduziu as emissões de CH4 e aumentou as emissões de N2O do solo, sendo a redução das emissões de CH4 mais significativa que a elevação nas emissões de N2O. Esse efeito foi maior para a conformação soja-soja-arroz, relativamente à conformação arroz-soja-arroz. O CH4 contribuiu com quase a totalidade (>95%) do PAGp da cultura de arroz, enquanto que o N2O foi o componente principal do PAGp da soja (>90%). As conformações de rotação envolvendo dois cultivos sucessivos (30.231 kg CO2 eq.) ou intercalados de arroz irrigado (28.153 kg CO2 eq.) proporcionaram PAGp superiores àquelas com dois cultivos de soja, respectivamente, 10.436 e 11.772 kg CO2 eq., para soja/arroz/soja e soja/soja/arroz. A rotação do arroz irrigado com soja reduz o potencial de aquecimento global dos sistemas de produção em terras baixas, constituindo-se em estratégia mitigadora de emissões de gases de efeito estufa.ODS 13