246 research outputs found
CombinaçÔes entre cultivares, ambientes, preparo e cobertura do solo em caracterĂsticas agronĂŽmicas de alface.
Objetivou-se identificar combinaçÔes entre cultivares, ambientes de cultivo e preparo e cobertura de solo capazes de melhorar o desempenho agronĂŽmico e aumentar a produtividade da cultura da alface em cultivo orgĂąnico. A pesquisa foi conduzida na Universidade Federal do Acre, utilizando o delineamento experimental de blocos casualizados, com parcelas subdivididas para cada experimento (campo e casa de vegetação), com quatro repetiçÔes. Em cada experimento, trĂȘs cultivares de alface (Simpson, Marisa e Vera), constituindo as sub-parcelas, foram sorteadas nas parcelas, representadas por quatro preparos e cobertura do solo (encanteiramento com cobertura de palha de arroz, polietileno prateado, solo descoberto e plantio direto). A produtividade comercial de alface foi de 12,3 t ha-1 em cultivo protegido e de 7,9 t ha-1 em campo. O cultivo protegido promoveu melhor desenvolvimento das plantas, caracterizado por maior massa da matĂ©ria fresca e seca da parte aĂ©rea, massa da matĂ©ria fresca comercial e melhor classificação comercial, alĂ©m de promover bom desempenho agronĂŽmico e maior produtividade em qualquer um dos preparos de solo. As cultivares Simpson e Marisa apresentaram massa da matĂ©ria seca da parte aĂ©rea semelhante e superior Ă âVeraâ, porĂ©m, o crescimento do caule da âSimpsonâ foi elevado, caracterizando pendoamento precoce, fato que reduz sua qualidade comercial. As cultivares Marisa e Vera nĂŁo alongaram o caule indicando serem tolerantes Ă s condiçÔes ambientais de Rio Branco. A cobertura do solo com casca de arroz ou plĂĄstico prateado contribuiu para minimizar os efeitos climĂĄticos prejudiciais ao cultivo da alface em campo. O plantio direto orgĂąnico nĂŁo diferiu do plantio em canteiro descoberto
Sedentary behavior in Brazilian children and adolescents: a systematic review
ABSTRACT OBJECTIVE To describe the methodological characteristics of the studies selected and assess variables associated with sedentary behavior in Brazilian children and adolescents. METHODS For this systematic review, we searched four electronic databases: PubMed, Web of Knowledge, LILACS, SciELO. Also, electronic searches were applied in Google Scholar. A supplementary search was conducted in the references lists of the included articles and in non-indexed journals. We included observational studies with children and adolescents aged from three to 19 years developed in Brazil, presenting analyses of associations based on regression methods and published until September 30, 2014. RESULTS Of the 255 potential references retrieved by the searches, 49 met the inclusion criteria and composed the descriptive synthesis. In this set, we identified a great number of cross-sectional studies (n = 43; 88.0%) and high methodological variability on the types of sedentary behavior assessed, measurement tools and cut-off points used. The variables most often associated with sedentary behavior were âhigh levels of body weightâ (in 15 out of 27 studies; 55.0%) and âlower level of physical activityâ (in eight out of 16 studies; 50.0%). CONCLUSIONS The findings of this review raise the following demands to the Brazilian agenda of sedentary behavior research geared to children and adolescents: development of longitudinal studies, validation of measuring tools, establishment of risk cut-offs, measurement of sedentary behavior beyond screen time and use of objective measures in addition to questionnaires. In the articles available, the associations between sedentary behavior with âhigh levels of body weightâ and âlow levels of physical activityâ were observed in different regions of Brazil
Dental calculus evidence of TaĂŻ Forest Chimpanzee plant consumption and life history transitions
Dental calculus (calcified dental plaque) is a source of multiple types of data on life history. Recent research has targeted the plant microremains preserved in this mineralised deposit as a source of dietary and health information for recent and past populations. However, it is unclear to what extent we can interpret behaviour from microremains. Few studies to date have directly compared the microremain record from dental calculus to dietary records, and none with long-term observation dietary records, thus limiting how we can interpret diet, food acquisition and behaviour. Here we present a high-resolution analysis of calculus microremains from wild chimpanzees (Pan troglodytes verus) of TaĂŻ National Park, CĂŽte d"Ivoire. We test microremain assemblages against more tan two decades of field behavioural observations to establish the ability of calculus to capture the composition of diet. Our results show that some microremain classes accumulate as long-lived dietary markers. Phytolith abundance in calculus can reflect the proportions of plants in the diet, yet this pattern is not true for starches. We also report microremains can record information about other dietary behaviours, such as the age of weaning and learned food processing techniques like nutcracking
Measurement of the cross-section of high transverse momentum vector bosons reconstructed as single jets and studies of jet substructure in pp collisions at âs = 7 TeV with the ATLAS detector
This paper presents a measurement of the cross-section for high transverse momentum W and Z bosons produced in pp collisions and decaying to all-hadronic final states. The data used in the analysis were recorded by the ATLAS detector at the CERN Large Hadron Collider at a centre-of-mass energy of âs = 7 TeV;{\rm Te}{\rm V}4.6\;{\rm f}{{{\rm b}}^{-1}}{{p}_{{\rm T}}}\gt 320\;{\rm Ge}{\rm V}|\eta |\lt 1.9{{\sigma }_{W+Z}}=8.5\pm 1.7$ pb and is compared to next-to-leading-order calculations. The selected events are further used to study jet grooming techniques
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