987 resultados para 391


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Mining activities are directly related to changes in natural landscapes. With the objective of analyzing the changes imposed by the geomorphological dynamics of human action in areas of mining clay, two fragments were selected from the basin of Ribeirão Santa Gertrudes / SP, representing denudational and sedimentation processes respectively. This area is within the context of the Ceramic Pole Santa Gertrudes / SP, which besides its importance as a supplier of raw material, is characterized as the largest center of international reference in ceramic tiles on the American continent. Data was collected and analyzed from the perspective of anthropogenic geomorphology supported by general systems theory and uses techniques from evolutionary geomorphological mapping. Thus, geomorphological mapping were produced concerning three scenarios, which date from 1962, 1988 and 2006 in a scale of 1:10.000. These surveys allowed us to infer a detailed investigation of the evolution of changes in topography and hydrology, geomorphology representative of the original (1962), which has characteristics of an earlier phase of earlier existing large mining pits, and its evolution to a anthropogenic geomorphological stage, represented by active disruption scenarios dating from 1988 and 2006. The last two scenarios have analyzed changes in the dimensions of relief features when compared with the original scenario representative of geomorphology, as well as an intense reallocation of surface and subsurface materials, in which human action is highlighted by becoming responsible for sculpting the landscape through the imposition of control mechanisms to natural processes.

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This study aims to understand the democratic and social potential of online citizen journalism, and how Storify can be use as a tool to achieve this goal. The focus is to analyse the use of this tool by media companies to verify if there are plurality of themes, or if there are gatekeeping of the information - such as occur in traditional media. The research will use the content analyse methodology to observe how three media companies use the website Storify: O Estado de São Paulo, Zero Hora and Veja. The results are based on the most frequent themes, which were divided into seven categories: police; politics; city; sport; technology; science and media. With this analyse we were able to concluded that, according to the theme, O Estado de Sao Paulo had, between the media companies analysed, the most plural approach, after it is Zero Hora, and lastly Veja.

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The study evaluated the energy balance of the yellow passion fruit (Passiflora edulis Sims) production system in the region of Marilia-SP. There were analyzed the "inputs" of energy originated from biological, fossil, and industrial sources, and the "output" of energy in the form of fruits produced per unit area, as well as five energy indicators. The phytotechnical indices considered were: planting in February (seedling in tubes), production cycle: 18 months, and yield: 20 t/ha. The input energy totaled 173,707.86 MJ/ha. The most representative items corresponded to industrial indirect energy (38%) and to biological (34%). Chemical fertilizers and pesticides accounted for 65% and 31% of indirect energy industry, respectively. The activity generated 391,800.00 MJ per cycle/ha, and the culture productivity, 0.12 MJ/kg. The efficiency of the culture was 2.26. The net cultural energy totaled 218,092.15 MJ/ha. The energy balance was positive (126,050.23 MJ/ha). Energy efficiency was favorable, with a value of 3.64. The direct power consumption of fossil origin is significant in the system evaluated, but it still allows the production of the yellow passion fruit in an environmentally sustainable way.

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The use of low quality water for agriculture should be performed with care to avoiding excessive accumulation of salts in the soil so not to harm crop development. In order to evaluate the performance of beets under the infl uence of low water quality, an experiment was conducted in a greenhouse of the Department of Agricultural Engineering, Universidade Estadual Paulista in Botucatu, Brazil, from April to July 2012. We used the beet (Beta vulgaris L.) in a completely randomized design with 6 treatments and 5 replications, totaling 30 plots. Treatments consisted of NaCl solutions at different concentrations (2.0, 3.0, 4.0, 5.0 and 6.0 dS m-1) plus a control treatment corresponding to water with no additional salt and electrical conductivity of roughly 0.26 dS m-1. Variables evaluated were total production, commercial production, plant height, number of plants and root diameter. Production of the beet crop was affected by the increasing salinity of irrigation water, characterized by reduced root production of the beets. Total and commercial production showed reductions of 8.82 and 12.2% in accordance with the unit increase of salinity.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Data was collected from 22 selected medical college libraries and 526 undergraduate and postgraduate medical students, using a survey. The article presents a list of findings and recommendations based on them to improve the services of medical college libraries in Andhra Pradesh.

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The relative growth and population structure of the terebellid Nicolea uspiana were investigated in the intertidal zone of a rocky shore on the south-east coast of Brazil, from May 2006 to May 2007. Eight hundred and forty-seven individuals of N. uspiana were analysed: 391 males, 163 females, and 293 immatures. Although significant differences in some morphometric parameters were found, there was no sexual dimorphism between males and females. There were differences in total length, width of segments, and length of the notopodial region between matures and immatures. The negative allometry of the total length in relation to five other parameters showed that this feature is a good measure for estimating the individual size, which was then used in the analysis of population structure. This population of N. uspiana showed a bimodal size frequency distribution, with immature and mature individuals found during the entire year. This pattern indicates continuous reproduction, with each cohort growing for at least three to four months and being responsible for two consecutive settlement peaks.

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We investigate the interface dynamics of the two-dimensional stochastic Ising model in an external field under helicoidal boundary conditions. At sufficiently low temperatures and fields, the dynamics of the interface is described by an exactly solvable high-spin asymmetric quantum Hamiltonian that is the infinitesimal generator of the zero range process. Generally, the critical dynamics of the interface fluctuations is in the Kardar-Parisi-Zhang universality class of critical behavior. We remark that a whole family of RSOS interface models similar to the Ising interface model investigated here can be described by exactly solvable restricted high-spin quantum XXZ-type Hamiltonians. (C) 2012 Elsevier B.V. All rights reserved.

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Many discussions have enlarged the literature in Bibliometrics since the Hirsch proposal, the so called h-index. Ranking papers according to their citations, this index quantifies a researcher only by its greatest possible number of papers that are cited at least h times. A closed formula for h-index distribution that can be applied for distinct databases is not yet known. In fact, to obtain such distribution, the knowledge of citation distribution of the authors and its specificities are required. Instead of dealing with researchers randomly chosen, here we address different groups based on distinct databases. The first group is composed of physicists and biologists, with data extracted from Institute of Scientific Information (IS!). The second group is composed of computer scientists, in which data were extracted from Google-Scholar system. In this paper, we obtain a general formula for the h-index probability density function (pdf) for groups of authors by using generalized exponentials in the context of escort probability. Our analysis includes the use of several statistical methods to estimate the necessary parameters. Also an exhaustive comparison among the possible candidate distributions are used to describe the way the citations are distributed among authors. The h-index pdf should be used to classify groups of researchers from a quantitative point of view, which is meaningfully interesting to eliminate obscure qualitative methods. (C) 2011 Elsevier B.V. All rights reserved.

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In general the term "Lagrangian coherent structure" (LCS) is used to make reference about structures whose properties are similar to a time-dependent analog of stable and unstable manifolds from a hyperbolic fixed point in Hamiltonian systems. Recently, the term LCS was used to describe a different type of structure, whose properties are similar to those of invariant tori in certain classes of two-dimensional incompressible flows. A new kind of LCS was obtained. It consists of barriers, called robust tori that block the trajectories in certain regions of the phase space. We used the Double-Gyre Flow system as the model. In this system, the robust tori play the role of a skeleton for the dynamics and block, horizontally, vortices that come from different parts of the phase space. (C) 2012 Elsevier B.V. All rights reserved.

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We examine hemolymph ion regulation and the kinetic properties of a gill microsomal (Na+, K+)-ATPase from the intertidal hermit crab, Clibanarius vittatus, acclimated to 45 parts per thousand salinity for 10 days. Hemolymph osmolality is hypo-regulated (1102.5 +/- 22.1 mOsm kg(-1) H2O) at 45 parts per thousand but elevated compared to fresh-caught crabs (801.0 +/- 40.1 mOsm kg(-1) H2O). Hemolymph [Na+ (323.0 +/- 2.5 mmol L-1) and [Me2+) (34.6 +/- 1.0 mmol L-1) are hypo-regulated while [Ca2+] (22.5 +/- 0.7 mmol L-1) is hyper-regulated; [K+] is hyper-regulated in fresh-caught crabs (17.4 +/- 0.5 mmol L-1) but hypo-regulated (6.2 +/- 0.7 mmol L-1) at 45 parts per thousand. Protein expression patterns are altered in the 45 parts per thousand-acclimated crabs, although Western blot analyses reveal just a single immunoreactive band, suggesting a single (Na+, K+)-ATPase alpha-subunit isoform, distributed in different density membrane fractions. A high-affinity (Vm = 46.5 +/- 3.5 U mg(-1); K-0.5 = 7.07 +/- 0.01 mu mol L-1) and a low-affinity ATP binding site (Vm = 108.1 +/- 2.5 U mg(-1); K-0.5 = 0.11 +/- 0.3 mmol L-1), both obeying cooperative kinetics, were disclosed. Modulation of (Na+, K+)-ATPase activity by Mg2+, K+ and NH4+ also exhibits site-site interactions, but modulation by Na+ shows Michaelis-Menten kinetics. (Na+, K+)-ATPase activity is synergistically stimulated up to 45% by NH4+ plus K+. Enzyme catalytic efficiency for variable [K+] and fixed [NH4+] is 10-fold greater than for variable [NH4+] and fixed [K+]. Ouabain inhibited approximate to 80% of total ATPase activity (K-I=464.7 +/- 23.2 mu mol L-1), suggesting that ATPases other than (Na+, K+)-ATPase are present. While (Na+, K+)-ATPase activities are similar in fresh-caught (around 142 nmol Pi min(-1) mg(-1)) and 45 parts per thousand-acclimated crabs (around 154 nmol Pi min(-1) mg(-1)), ATP affinity decreases 110-fold and Na+ and K+ affinities increase 2-3-fold in 45 parts per thousand-acclimated crabs. (C) 2012 Elsevier Inc. All rights reserved.