Produtividade da bananeira Prata Anã sob diferentes sistemas de irrigação em condições de agricultura familiar no Semiárido.

Os assentamentos ribeirinhos localizados no semi-árido apresentam limitações em relação ao acesso à tecnologia de produção em fruticultura, fato que resulta em dificuldade de viabilizarem-se produtivamente e economicamente. A caracterização do perfil produtivo da agropecuária nos assentamentos é pré-requisito para o planejamento de programas de desenvolvimento que visam melhorar a produtividade a partir de investimentos em tecnologias aplicáveis à agricultura familiar, de forma a favorecer o desenvolvimento integrado e sustentável. Este trabalho teve como objetivo avaliar três sistemas de irrigação em uma área plantada com bananeira (cultivar Prata Anã) no espaçamento de 3,0 x 2,5 m, em um assentamento no semiárido da Bahia. Adotou-se o delineamento experimental em blocos ao acaso, com quatro repetições, sendo que os tratamentos consistiram de três sistemas de irrigação (S1-bacia alimentada por canal revestido, S2- microaspersão adaptada e S3-gotejamento adaptado). O uso dos sistemas propostos para agricultura familiar teve efeito sobre as variáveis diâmetro do fruto, numero de fruto e peso do cacho, todavia não houve diferença entre as médias para comprimento de penca e peso de penca. As maiores médias absolutas das variáveis de produção analisadas foram obtidas do sistema S3

Un análisis multinivel de población y deforestación en el Parque Nacional Sierra de Lacandón (Petén, Guatemala)

Este estudio examina los factores demográficos asociados con la deforestación en el Parque Nacional Sierra de Lacandón (PNSL), Guatemala, utilizando un análisis de regresión multinivel. Más del 10% del PNSL ha sido deforestado desde mediados de la década de 1980, a causa del crecimiento demográfico de la población campesina y su subsiguiente manejo de la tierra. Utilizando un análisis de regresión múltiple de dos niveles, este estudio examina datos demográficos y otras características de los hogares para explicar variaciones en el bosque roturado entre 241 fincas agrícolas en ocho comunidades en el PNSL. Esta metodología, novedosa en el estudio de uso del suelo en los trópicos, toma en cuenta la variación espacial entre comunidades, así como entre hogares. Al usar modelos de multinivel, se puede llegar a resultados mejores sobre los impactos de los factores, tanto a nivel de comunidad como a nivel de hogar sobre la deforestación, con implicaciones más adecuadas para políticas de desarrollo.Aquest estudi examina els factors demogràfics associats amb la desforestació al Parc Nacional Sierra de Lacandon (PNSL), Guatemala, mitjançant una anàlisi de regressió multinivell. Més del 10 % del PNSL ha estat desforestat des de la meitat de la dècada de 1980, com a conseqüència del creixement demogràfic i les pràctiques de gestió agrícola. Utilitzant una anàlisi de regressió múltiple de dos nivells, aquest estudi examina dades demogràfiques i unes altres característiques de les llars per explicar variacions en el bosc artigat entre 241 finques agrícoles en vuit comunitats al PNSL. Aquesta metodologia té en compte la variació especial entre comunitats i entre llars, i abans no havia estat mai aplicada als tròpics. El model de regressió multinivell pot ajudar a explicar millor els impactes de factors propis de les comunitats i de les llars en la desforestació, per tant, pot contribuir a millorar les polítiques de desenvolupament.Cette étude a examiné les facteurs démographiques associés au phénomène de déforestation du Parc National Sierra de Lacandón (PNSL, Guatemala) en utilisant une analyse de régression multi-niveau. Depuis le milieu des années 1980, plus de 10 % du PNSL a été déboisé par la croissance démographique de la population rurale, son besoin en surface et l'utilisation variée de la terre. En utilisant une analyse de régression multiple de deux niveaux, cette étude examine des données démographiques et plusieurs caractéristiques liées aux exploitations, dans le but d'expliquer les variations dans le parc défriché entre 241 propriétés agricoles dans huit communautés du PNSL. Cette méthodologie, nouvelle dans l'étude de l'usage du sol dans les tropiques, prend en compte la variation spatiale entre des communautés ainsi que des exploitations. En utilisant ces modèles de multi-niveaux, on peut arriver à de meilleurs résultats concernant les impacts des facteurs au niveau des communautés et des exploitations concernant la déforestation, avec des résultats plus adapatées pour les politiques de développement.The paper examines depopulation factors associated with deforestation in the Natural park of the Sierra de Lacandón (PNSL), using multi-level regresión analysis. More than 10 percent of the park area has been deforested since the mid 1980s because of rural population growth and agricultural practices. By means of a two-level regression analysis the study use dem ographic and other household data to explain variations in deforested land in 241 agricultural estates in 8 communities of the PNSL. The methodology, not applied before in the tropics, takes into account spatial variations between communities and households. Multilvel regression allows for better results on the impacts of socioeconomic factors on deforestation, both at the community and at the household levels with important implications for development policies

Atorvastatin and sildenafil decrease vascular TGF-β levels and MMP-2 activity and ameliorate arterial remodeling in a model of renovascular hypertension

AbstractImbalanced matrix metalloproteinase (MMP)-2 activity and transforming growth factor expression (TGF-β) are involved in vascular remodeling of hypertension. Atorvastatin and sildenafil exert antioxidant and pleiotropic effects that may result in cardiovascular protection. We hypothesized that atorvastatin and sildenafil alone or in association exert antiproliferative effects by down-regulating MMP-2 and TGF-β, thus reducing the vascular hypertrophy induced by two kidney, one clip (2K1C) hypertension.Sham and 2K1C rats were treated with oral atorvastatin 50mg/kg, sildenafil 45mg/kg, or both, daily for 8 weeks. Blood pressure was monitored weekly. Morphologic changes in the aortas were studied. TGF-β levels were determined by immunofluorescence. MMP-2 activity and expression were determined by in situ zymography, gel zymography, Western blotting, and immunofluorescence. The effects of both drugs on proliferative responses of aortic smooth muscle cells to PDGF and on on MMP-2 activity in vitro were determined. Atorvastatin, sildenafil, or both drugs exerted antiproliferative effects in vitro. All treatments attenuated 2K1C-induced hypertension and prevented the increases in the aortic cross-sectional area and media/lumen ratio in 2K1C rats. Aortas from 2K1C rats showed higher collagen deposition, TGF-β levels and MMP-2 activity and expression when compared with Sham-operated animals. Treatment with atorvastatin and/or sildenafil was associated with attenuation of 2K1C hypertension-induced increases in these pro-fibrotic factors. However, these drugs had no in vitro effects on hr-MMP-2 activity.Atorvastatin and sildenafil was associated with decreased vascular TGF-β levels and MMP-2 activity in renovascular hypertensive rats, thus ameliorating the vascular remodeling. These novel pleiotropic effects of both drugs may translate into protective effects in patients

Biodiversidade, população e economia: uma região de mata atlântica [Biodiversity, Population, and Economy: a region of atlantic forest]

Minas Gerais; Rio Doce; mata atlântica; atlantic forest; sustainable development; conservation; regional development; environment

Biodiversidade, população e economia: uma região de mata atlântica [Biodiversity, Population, and Economy: a region of atlantic forest]

Minas Gerais; Rio Doce; mata atlântica; atlantic forest; sustainable development; conservation; regional development; environment

Influence of Altitude on the indirect Analysis of α-amylase Content on Wheat Flours

The objective of this study was to verify the influence of altitude on the indirect analysis of α-amylase content on wheat flours. The experimental designused was completely randomized, with eight treatments and three repetitions. The treatments consisted of the analysis of the falling number from flours of four wheat classes (basic, domestic, bread and improver) on the elevations zero, 412, 540, 761, 934, 975, 1,040 and 1,095 meters. After the trial results, under the correction of the averages above 600 meters of elevation, it was verified that there was a significant difference between the results of distinct altitudes, for the four wheat classes. When a polynomial regression is applied, for the values without correction, it was obtained that aquadratic regression equation correlates the falling number values with altitude; however, the coefficient of determination was very low, highlighting the major influence of the different equipments that were used to measure the falling number instead of the different altitudes

Using Theory to Guide Exploratory Network Analyses

The use of exploratory network analysis has increased in psychopathology research over the past decade. A benefit of exploratory network analysis is the wealth of information it can provide; however, a single analysis may generate more inferences than what can be discussed in one manuscript (e.g., centrality indices of each node). This necessitates that authors choose which results to discuss in further detail and which to omit. Without a guide for this process, the likelihood of a biased interpretation is high. We propose that the integration of theory throughout the research process makes the interpretation of exploratory networks more manageable for the researcher and more likely to result in an interpretation that advances science. The goals of this paper are to differentiate between exploratory and confirmatory network analyses, discuss the utility of exploratory work, and provide a practical framework that uses theory as a guide to interpret exploratory network analyses