853 resultados para Compactness Compensated


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The morphometric characterization of watersheds is of great importance in assisting the planning of these areas to preserve the environment and maintain the quantity and quality of water production. The aim of this study was to characterize the morphology and simulate the areas of permanent preservation according to the Brazilian Forest Code of watershed of the Água-Fria stream. The studied area is located in the municipality of Bofete-SP, between the geographic coordinates: 48° 09' 30" to 48° 18' 30" longitude (WGr) and 22° 58' 30" to 23° 04' 30" latitude S. The results showed a 5th order micro watershed with an area of 152.43 km2 and low drainage density of 1.04 km/km2. Circularity was 0.51 and form factor was 0.41, which is considered low, and therefore with an oblong/oval shape. The sinuosity index of 1.29 revealed a tendency of rectilinear channels with compactness coefficient value of 1.38 and distance of runoff flow of 520m. Simulation of areas of permanent preservation shows an ideal model as the way springs and watercourses should be protected according to the Brazilian Forest Code, amounting to an area of 10.02 km2.

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In crop-livestock integration systems the presence of both grass roots in the soil and straw on the surface can temporarily immobilize nitrogen. This study examined the persistence of grass residues in the system as well as their effects on cotton response to N when grown after Congo grass (Brachiaria ruziziensis, Syn. Urochloa ruziziensis). Congo grass was grown in pots with soil. Next, cotton was grown in the same pots without residues, with whole plant residues (Congo grass roots and shoots) or root residues (grass roots) and fertilized with N as ammonium nitrate. Congo grass and cotton roots were separated using stable carbon isotope fractioning. Congo grass roots showed higher C/N ratio than shoots, losing 14% of its mass after 45 days and increasing soil N immobilization. The lower N availability resulted in N deficient and shorter cotton plants with lower dry matter yields. Nevertheless, the application of 80 to 120 mg kg-1 of N compensated the immobilization by the soil microorganisms, allowing cotton to show normal growth. When Congo grass is present in the cropping system, the effects of the decaying roots on soil N dynamics and availability are more important than those of the straw left on the soil surface.

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Pós-graduação em Física - IFT

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This paper deals with the homologation process for obtaining carbon credits through the Clean Development Mechanism (CDM), that regulates the greenhouse gases reductions under the rules of the Kyoto Protocol. The CDM evaluates projects through a project cycle, which begins with the preparation of the Project Design Document (PDD) until the project certification to receive Certified Emission Reductions (CERs), popularly known as carbon credits. This study analyzed the implementation of the system Burner Recorder System for Low Flows of Biogas (QRBBV), developed by Marcelino Junior & Godoy (2009), in an eco-friendly wastewater treatment mini-plant (miniEETERA), built at the site of UNESP - Guaratinguetá SP. The QRBBV system is low cost and high reliability, developed to burn the methane generated at sites of low and variable production of biogas, which is not economically justified their energy recovery. Currently, almost all wastewater generated at the site of the campus is being treated by miniEETERA and, as a result, the biogas originated by this activity is being released into the atmosphere. Therefore, the project activity aims to capture and burn the biogas generated by miniEETERA, reducing the negative effects caused by the methane emissions into the atmosphere and, thus, claim to receive carbon credits. This work aimed to demonstrate the project applicability under CDM through the study and preparation of the PDD, as well as an analysis of the entire project cycle required for homologation. The result of the work obtained an estimate of only 20 CERs per year and proved to be economically unviable for approval through the CDM, since the spending with the approval process would not be compensated with the sale of CERs, mainly due the low carbon price in the world market. From an environmental standpoint, the project is perfectly... (Complete abstract click electronic access below)

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Topics include: Topological space and continuous functions (bases, the product topology, the box topology, the subspace topology, the quotient topology, the metric topology), connectedness (path connected, locally connected), compactness, completeness, countability, filters, and the fundamental group.

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This paper deals with the homologation process for obtaining carbon credits through the Clean Development Mechanism (CDM), that regulates the greenhouse gases reductions under the rules of the Kyoto Protocol. The CDM evaluates projects through a project cycle, which begins with the preparation of the Project Design Document (PDD) until the project certification to receive Certified Emission Reductions (CERs), popularly known as carbon credits. This study analyzed the implementation of the system Burner Recorder System for Low Flows of Biogas (QRBBV), developed by Marcelino Junior & Godoy (2009), in an eco-friendly wastewater treatment mini-plant (miniEETERA), built at the site of UNESP - Guaratinguetá SP. The QRBBV system is low cost and high reliability, developed to burn the methane generated at sites of low and variable production of biogas, which is not economically justified their energy recovery. Currently, almost all wastewater generated at the site of the campus is being treated by miniEETERA and, as a result, the biogas originated by this activity is being released into the atmosphere. Therefore, the project activity aims to capture and burn the biogas generated by miniEETERA, reducing the negative effects caused by the methane emissions into the atmosphere and, thus, claim to receive carbon credits. This work aimed to demonstrate the project applicability under CDM through the study and preparation of the PDD, as well as an analysis of the entire project cycle required for homologation. The result of the work obtained an estimate of only 20 CERs per year and proved to be economically unviable for approval through the CDM, since the spending with the approval process would not be compensated with the sale of CERs, mainly due the low carbon price in the world market. From an environmental standpoint, the project is perfectly... (Complete abstract click electronic access below)

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The Rio de la Plata waters form a low salinity tongue that affects the circulation, stratification and the distributions of nutrients and biological species over a wide extent of the adjacent continental shelf. The plume of coastal waters presents a seasonal meridional displacement reaching lower latitudes (28,S) during austral winter and 32 degrees S during summer. Historical data suggests that the wind causes the alongshore shift, with southwesterly (SW) winds forcing the plume to lower latitudes in winter while summer dominant northeasterly (NE) winds force its southward retreat. To establish the connection between wind and outflow variations on the distribution of the coastal waters, we conducted two quasi-synoptic surveys in the region of Plata influence on the continental shelf and slope of southeastern South America, between Mar del Plata, Argentina and the northern coast of Santa Catarina, Brazil. We observed that: (A) SW winds dominating in winter force the northward spreading of the plume to low latitudes even during low river discharge periods; (B) NE winds displace the plume southward and spread the low salinity waters offshore over the entire width of the continental shelf east of the Plata estuary. The southward retreat of the plume in summer leads to a volume decrease of low salinity waters over the shelf. This volume is compensated by an increase of Tropical waters, which dominate the northern shelf. The subsurface transition between Subantarctic and Subtropical Shelf Waters, the Subtropical Shelf Front, and the subsurface water mass distribution, however, present minor seasonal variations. Along shore winds also influence the dynamics and water mass variations along the continental shelf area. In areas under the influence of river discharge, Subtropical Shelf Waters are kept away from the coastal region. When low salinity waters retreat southward, NE winds induce a coastal upwelling system near Santa Marta Cape. In summer, solar radiation promotes the establishment of a strong thermocline that increases buoyancy and further enhances the offshore displacement of low salinity waters under the action of NE winds. (C) 2008 Elsevier Ltd. All rights reserved.

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Although the biopolymer poly-(3-hydroxybutyrate), P[3HB], presents physicochemical properties that make it an alternative material to conventional plastics, its biotechnological production is quite expensive. As carbon substrates contribute greatly to P[3HB] production cost, the utilization of a cheaper carbon substrate and less demanding micro-organisms should decrease its cost. In the present study a 23 factorial experimental design was applied, aiming to evaluate the effects of using hydrolysed corn starch (HCS) and soybean oil (SBO) as carbon substrates, and cheese whey (CW) supplementation in the mineral medium (MM) on the responses, cell dried weigh (DCW), percentage P[3HB] and mass P[3HB] by recombinant Escherichia coli strains JM101 and DH10B, containing the P[3HB] synthase genes from Cupriavidus necator (ex-Ralstonia eutropha). The analysis of effects indicated that the substrates and the supplement and their interactions had positive effect on CDW. Statistically generated equations showed that, at the highest concentrations of HCS, SO and CW, theoretically it should be possible to produce about 2 g L(1) DCW, accumulating 50% P[3HB], in both strains. To complement this study, the strain that presented the best results was cultivated in MM added to HCS, SBO and CW ( in best composition observed) and complex medium (CM) to compare the obtained P[3HB] in terms of physicochemical parameters. The obtained results showed that the P[3HB] production in MM (1.29 g L(-1)) was approximately 20% lower than in CM (1.63 g L(-1)); however, this difference can be compensated by the lower cost of the MM achieved by the use of cheap renewable carbon sources. Moreover, using differential scanning calorimetry and thermogravimetry analyses, it was observed that the polymer produced in MM was the one which presented physicochemical properties (Tg and Tf) that were more similar to those found in the literature for P[3HB].

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A correlation between lattice parameters, oxygen composition, and the thermoelectric and Hall coefficients is presented for single-crystal Li0.9Mo6O17, a quasi-one-dimensional (Q1D) metallic compound. The possibility that this compound is a compensated metal is discussed in light of a substantial variability observed in the literature for these transport coefficients.

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We study local rigidity and multiplicity of constant scalar curvature metrics in arbitrary products of compact manifolds. Using (equivariant) bifurcation theory we determine the existence of infinitely many metrics that are accumulation points of pairwise non-homothetic solutions of the Yamabe problem. Using local rigidity and some compactness results for solutions of the Yamabe problem, we also exhibit new examples of conformal classes (with positive Yamabe constant) for which uniqueness holds. (C) 2011 Elsevier Masson SAS. All rights reserved.

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The use of cover crops affects the support capacity of soil and least limiting water range to crop growth. The objective of this study was to quantify preconsolidation pressure (sigma(p)), compression index (CI) and least limiting water range (LLWR) of a reclaimed coal mining soil under different cover crops, in Candiota, RS, Brazil. In the experiment, with randomized blocks design and four replicates, the following cover crops (treatments) were evaluated: Hemarthria altissima (Poir.) Stapf & C.E. Hubbard, treatment 1 (T1), Paspalum notatum Flugge, treatment 4 (T4), Cynodon dactilon (L) Pers., treatment 5 (T5), control Brachiaria brizantha (Hochst.) Stapf, treatment 7 (T7) and without cover crop treatment 8 (reference treatment, T8). Soil compression and least limiting water range were evaluated with undisturbed samples at a depth of 0.00-0.05 m. In order to evaluate parameters of soil compressibility, the soil samples were saturated with water and subjected to -10 kPa matric potential and then submitted to a uniaxial compression test under the following pressures: 25, 50, 100, 200, 400, 800 and 1600 kPa. Cover crops decreased the preconsolidation pressure of constructed soils after coal mining and the greatest soil reclamation was obtained with the H. altissima cover crop, where the lowest degree of soil compactness and soil load capacity were observed. Soils cultivated under H. altissima or B. brizantha presented the highest least limiting water range and these two cover crops generated similar soil critical bulk density obtained by least limiting water range and soil load support capacity. (C) 2012 Elsevier B.V. All rights reserved.

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The heart responds to sustained overload by hypertrophic growth in which the myocytes distinctly thicken or elongate on increases in systolic or diastolic stress. Though potentially adaptive, hypertrophy itself may predispose to cardiac dysfunction in pathological settings. The mechanisms underlying the diverse morphology and outcomes of hypertrophy are uncertain. Here we used a focal adhesion kinase (FAK) cardiac-specific transgenic mice model (FAK-Tg) to explore the function of this non-receptor tyrosine kinase on the regulation of myocyte growth. FAK-Tg mice displayed a phenocopy of concentric cardiac hypertrophy, reflecting the relative thickening of the individual myocytes. Moreover, FAK-Tg mice showed structural, functional and molecular features of a compensated hypertrophic growth, and preserved responses to chronic pressure overload. Mechanistically, FAK overexpression resulted in enhanced myocardial FAK activity, which was proven by treatment with a selective FAK inhibitor to be required for the cardiac hypertrophy in this model. Our results indicate that upregulation of FAK does not affect the activity of Src/ERK1/2 pathway, but stimulated signaling by a cascade that encompasses PI3K, AKT, mTOR, S6K and rpS6. Moreover, inhibition of the mTOR complex by rapamycin extinguished the cardiac hypertrophy of the transgenic FAK mice. These findings uncover a unique role for FAK in regulating the signaling mechanisms that governs the selective myocyte growth in width, likely controlling the activity of PI3K/AKT/mTOR pathway, and suggest that FAK activation could be important for the adaptive response to increases in cardiac afterload. This article is part of a Special Issue entitled "Local Signaling in Myocytes". (C) 2011 Elsevier Ltd. All rights reserved.

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Mach number and thermal effects on the mechanisms of sound generation and propagation are investigated in spatially evolving two-dimensional isothermal and non-isothermal mixing layers at Mach number ranging from 0.2 to 0.4 and Reynolds number of 400. A characteristic-based formulation is used to solve by direct numerical simulation the compressible Navier-Stokes equations using high-order schemes. The radiated sound is directly computed in a domain that includes both the near-field aerodynamic source region and the far-field sound propagation. In the isothermal mixing layer, Mach number effects may be identified in the acoustic field through an increase of the directivity associated with the non-compactness of the acoustic sources. Baroclinic instability effects may be recognized in the non-isothermal mixing layer, as the presence of counter-rotating vorticity layers, the resulting acoustic sources being found less efficient. An analysis based on the acoustic analogy shows that the directivity increase with the Mach number can be associated with the emergence of density fluctuations of weak amplitude but very efficient in terms of noise generation at shallow angle. This influence, combined with convection and refraction effects, is found to shape the acoustic wavefront pattern depending on the Mach number.

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Using recent results on the compactness of the space of solutions of the Yamabe problem, we show that in conformal classes of metrics near the class of a nondegenerate solution which is unique (up to scaling) the Yamabe problem has a unique solution as well. This provides examples of a local extension, in the space of conformal classes, of a well-known uniqueness criterion due to Obata.