999 resultados para Raoul Ruiz


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During the past 40 years colluvial and alluvial deposits have been used in Brazil as good indicators of regional landscape sensitivity to Quaternary environmental changes. In spite of the low resolution of most of the continental sedimentary record, geomorphology and sedimentology may favor palaeoenvironmental interpretation when supported by independent proxy data. This paper presents results obtained from pedostratigraphic sequences, in near-valley head sites of southern Brazilian highlands, based on geomorphologic. sedimentologic, micromorphologic, isotopic and palynologic data. Results point to environmental changes, with ages that coincide with Marine Isotopic Stages (MIS) 5b; 3; 2 and 1. During the late Pleistocene, although under temperatures and precipitation lower than today, the local record points to relatively wet local environments, where shallow soil-water saturated zones contributed to erosion and sedimentation during periods of climatic change, as during the transition between MIS 2 and MIS 1. Late Pleistocene events with ages that coincide with the Northern Hemisphere Younger Dryas are also depicted. During the mid Holocene, slope-wash deposits suggest a climate drier than today, probably under the influence of seasonally contrasted precipitation regimes. The predominance of overland flow-related sedimentary deposits suggests an excess of precipitation over evaporation that influenced local palaeohydrology. This environmental condition seems to be recurrent and explains how slope morphology had influenced pedogenesis and sedimentation in the study area. Due to relative sensitiveness, resilience and short source-to-sink sedimentary pathways, near-valley head sites deserve further attention in Quaternary studies in the humid tropics. (c) 2008 Elsevier B.A. All rights reserved.

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Twenty-two (14)C datings were performed at the central sector of the Parana coast to define Holocene regressive barrier evolution. The barrier Pleistocene substratum was ascribed an age between 40400 and 30000 yr BP, but it can also represent the penultimate sea level highstand during marine isotope stage 5e. The Holocene barrier samples provided ages between 8542-8279 and 2987-2751 cal yr BP, and showed at least six age inversions that were related to age differences between in situ or low-distance transported shells or trunk fragments, and high-distance transported vegetal debris, wood fragments and organic matter samples. The regressive Holocene barrier age was 4402-4135 cal yr BP near the base, and 2987-2751 cal yr BP near the top. Most of the vegetal remains were transported by ebb tidal currents from the estuaries to the inner shelf below wave base level during the mid-Holocene highstand; they were transported onshore by storm waves and littoral currents during the sea level lowering after the sea level maximum, and were deposited mainly as middle shoreface swaley cross-stratification facies. (C) 2008 Published by Elsevier B.V.

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The aim of this study is to describe the changes in nursing education during the process prior to and after the establishment of democracy in Spain. It begins with the hypothesis that differences in social and political organization influenced the way the system of nursing education evolved, keeping it in line with neopositivistic schemes and exclusively technical approaches up until the advent of democracy. The evolution of a specific profile for nursing within the educational system has been shaped by the relationship between the systems of social and political organization in Spain. To examine the insertion of subjects such as the anthropology of healthcare into education programs for Spanish nursing, one must consider the cultural, intercultural and transcultural factors that are key to understanding the changes in nursing education that allowed for the adoption of a holistic approach in the curricula. Until the arrival of democracy in 1977, Spanish nursing education was solely technical in nature and the role of nurses was limited to the tasks and procedures defined by the bureaucratic thinking characteristic of the rational-technological paradigm. Consequently, during the long period prior to democracy, nursing in Spain was under the influence of neopositivistic and technical thinking, which had its effect on educational curricula. The addition of humanities and anthropology to the curricula, which facilitated a holistic approach, occurred once nursing became a field of study at the university level in 1977, a period that coincided with the beginnings of democracy in Spain.

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Background: violence against women is a serious problem caused by the social construction of feminineness and masculineness that results in the domination of women by men. Public policies on gender have recently been developed in order to confront the problem. But what exactly are the problems faced by women? Purposes: to survey and analyse cases of violence against women reported to the police, as recorded at the Police Stations for Women`s Defence (PSWDs), and to reconstruct the procedures that women must go through in order to denounce their aggressors. Methodology: this quantitative, exploratory and descriptive study was undertaken during 2006-2007 in the city of Itapevi, Sao Paulo metropolitan region, Brazil. As there is no PSWD data were collected from police reports from PSWDs of neighbouring cities. Findings: malicious physical injury (49%) and threats (42%) were the most commonly reported types of violence. The victims were aged between 20 and 49 years (93%). Almost all of the aggressors (97%) were men and most had an intimate relationship with their victim. The use of alcoholic beverages was linked to approximately 25% of the cases. Conclusion: women who are victims of domestic violence in Itapevi report that going through PSWDs of neighbouring cities is a difficult, isolated, long and expensive process that often, provides no institutional protection. Implications for practice: there is an urgent requirement for judicial-assistance and support close to home in order to provide a quality service and follow-up for these women and their aggressors; to provide training for the professionals called to attend them at police stations; and for a caring attitude from health-care professionals.,0 2010 Elsevier Ltd. All rights reserved.

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Aim To describe the perceptions and attitudes of registered nurses (RNs) towards adverse events (AEs) in nursing care. Background The professionals` subjective perspectives should be taken into account for the prevention of AEs in care settings. Method Schutz`s social phenomenology was developed. Interviews were conducted with nine Intensive Care Unit RNs. Results The following five descriptive categories emerged: (1) the occurrence of AEs is inherent to the human condition but provokes a feeling of insecurity, (2) the occurrence of AEs indicates the existence of failures in health care systematization, (3) the professionals` attitudes towards AEs should be permeated by ethical principles; (4) the priority regarding AEs should be the mitigation of harm to patients, and (5) decisions regarding the communication of AEs were determined by the severity of the error. Conclusions The various subjective perspectives related to the occurrence of AEs requires a health care systematization with a focus on prevention. Ethical behaviour is essential for the patients` safety. Implications for nursing management Activities aimed at the prevention of AEs should be integrated jointly with both the professionals and the health care institution. A culture of safety, not punishment, and improvement in the quality of care provided to patients should be priorities.

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Fourier transform near infrared (FT-NIR) spectroscopy was evaluated as an analytical too[ for monitoring residual Lignin, kappa number and hexenuronic acids (HexA) content in kraft pulps of Eucalyptus globulus. Sets of pulp samples were prepared under different cooking conditions to obtain a wide range of compound concentrations that were characterised by conventional wet chemistry analytical methods. The sample group was also analysed using FT-NIR spectroscopy in order to establish prediction models for the pulp characteristics. Several models were applied to correlate chemical composition in samples with the NIR spectral data by means of PCR or PLS algorithms. Calibration curves were built by using all the spectral data or selected regions. Best calibration models for the quantification of lignin, kappa and HexA were proposed presenting R-2 values of 0.99. Calibration models were used to predict pulp titers of 20 external samples in a validation set. The lignin concentration and kappa number in the range of 1.4-18% and 8-62, respectively, were predicted fairly accurately (standard error of prediction, SEP 1.1% for lignin and 2.9 for kappa). The HexA concentration (range of 5-71 mmol kg(-1) pulp) was more difficult to predict and the SEP was 7.0 mmol kg(-1) pulp in a model of HexA quantified by an ultraviolet (UV) technique and 6.1 mmol kg(-1) pulp in a model of HexA quantified by anion-exchange chromatography (AEC). Even in wet chemical procedures used for HexA determination, there is no good agreement between methods as demonstrated by the UV and AEC methods described in the present work. NIR spectroscopy did provide a rapid estimate of HexA content in kraft pulps prepared in routine cooking experiments.

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The general flowshop scheduling problem is a production problem where a set of n jobs have to be processed with identical flow pattern on in machines. In permutation flowshops the sequence of jobs is the same on all machines. A significant research effort has been devoted for sequencing jobs in a flowshop minimizing the makespan. This paper describes the application of a Constructive Genetic Algorithm (CGA) to makespan minimization on flowshop scheduling. The CGA was proposed recently as an alternative to traditional GA approaches, particularly, for evaluating schemata directly. The population initially formed only by schemata, evolves controlled by recombination to a population of well-adapted structures (schemata instantiation). The CGA implemented is based on the NEH classic heuristic and a local search heuristic used to define the fitness functions. The parameters of the CGA are calibrated using a Design of Experiments (DOE) approach. The computational results are compared against some other successful algorithms from the literature on Taillard`s well-known standard benchmark. The computational experience shows that this innovative CGA approach provides competitive results for flowshop scheduling; problems. (C) 2007 Elsevier Ltd. All rights reserved.

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The Generalized Finite Element Method (GFEM) is employed in this paper for the numerical analysis of three-dimensional solids tinder nonlinear behavior. A brief summary of the GFEM as well as a description of the formulation of the hexahedral element based oil the proposed enrichment strategy are initially presented. Next, in order to introduce the nonlinear analysis of solids, two constitutive models are briefly reviewed: Lemaitre`s model, in which damage and plasticity are coupled, and Mazars`s damage model suitable for concrete tinder increased loading. Both models are employed in the framework of a nonlocal approach to ensure solution objectivity. In the numerical analyses carried out, a selective enrichment of approximation at regions of concern in the domain (mainly those with high strain and damage gradients) is exploited. Such a possibility makes the three-dimensional analysis less expensive and practicable since re-meshing resources, characteristic of h-adaptivity, can be minimized. Moreover, a combination of three-dimensional analysis and the selective enrichment presents a valuable good tool for a better description of both damage and plastic strain scatterings.

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Rotifera density, biomass, and secondary production on two marginal lakes of Paranapanema River were compared after the recovery of hydrologic connectivity with the river (Sao Paulo State, Brazil). Daily samplings were performed in limnetic zone of both lakes during the rainy season immediately after lateral inflow of water and, in the dry period, six months after hydrologic connectivity recovery. In order to identify the factors that affect rotifer population dynamics, lake water level, volume, depth, temperature, transparency, dissolved oxygen, pH, alkalinity, conductivity, suspended solids, nutrients, and chlorophyll-a were determined. Variations of water physical and chemical factors that affect rotifer population were related to the lake-river degree of connection and to water level rising after drought. The water lateral inflow from the river resulted in an increase in lake water volume, depth, and transparency and a decrease in water pH, alkalinity, and suspended solids. The lake with the wider river connection, more frequent biota exchange, and larger amount of particulate and dissolved materials was richer and more diverse, while rotifer density, biomass, and productivity were lower in both periods studied. Density, biomass, and secondary production were higher in the lake with the smaller river connection and the higher physical and chemical stability. Our results show that the connectivity affects the limnological stability, associated to seasonality. Stable conditions, caused by low connectivity in dry periods, were related with high density, biomass and secondary production. Conversely, instability conditions in rainy periods were associated to elevated richness and diversity values, caused by exchange biota due to higher connectivity. (C) 2008 Elsevier GmbH. All rights reserved.

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Tropical countries, such as Brazil and Colombia, have the possibility of using agricultural lands for growing biomass to produce bio-fuels such as biodiesel and ethanol. This study applies an energy analysis to the production process of anhydrous ethanol obtained from the hydrolysis of starch and cellulosic and hemicellulosic material present in the banana fruit and its residual biomass. Four different production routes were analyzed: acid hydrolysis of amylaceous material (banana pulp and banana fruit) and enzymatic hydrolysis of lignocellulosic material (flower stalk and banana skin). The analysis considered banana plant cultivation, feedstock transport, hydrolysis, fermentation, distillation, dehydration, residue treatment and utility plant. The best indexes were obtained for amylaceous material for which mass performance varied from 346.5 L/t to 388.7 L/t, Net Energy Value (NEV) ranged from 9.86 MJ/L to 9.94 MJ/L and the energy ratio was 1.9 MJ/MJ. For lignocellulosic materials, the figures were less favorable: mass performance varied from 86.1 to 123.5 L/t, NEV from 5.24 10 8.79 MJ/L and energy ratio from 1.3 to 1.6 MJ/MJ. The analysis showed, however, that both processes can be considered energetically feasible. (C) 2010 Elsevier Ltd. All rights reserved.

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An alternative for ethanol production, is the use of vegetable waste, such as excess of banana production, that are evaluated in 2,400,000 t/year, which includes: residual banana fruit and lignocellulosic material. This paper analyzes the energetic and exergetic behavior to carry the process developed at laboratory scale to a plant processing of banana for the ethanol production, involving: growing and transport of the vegetable material, hydrolysis of banana fruit, sugar fermentation, ethanol distillation and utility plant. Finally, energy and exergy indicators are obtained. The results show a positive energy balance when banana fruit is used for ethanol production, but some process modification must be done looking for improving the exergetic efficiency in ethanol production.

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The processes involved in coal preparation produce harmful effects for the environment, mainly by the quantity and nature Of wastes that are generated, These tailings generally called ""pyritic"", even though not presenting a high pyrite content, are an acid material harmful to the environment. These tailings are usually disposed of in tailings dams. The tailings, studied in this work come from a process involving dense-medium cyclones and spirals. They have an ash content of 56% and a calorific value of 5,800 BTU/Lb, the sulfur content is 1.2%. In terms of size, the material is considered as ultrafine, as 63% of it is less than 0,014 mm. The coal matter content of these tailings is easily recovered by froth flotation, as evidenced in this work. It possible to recover 74% of the coal matter and to obtain a product with 7.3% ash and calorific value of 14,225 BTU/lb in dry basis.

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This article presents a kinetic evaluation of froth flotation of ultrafine coal contained in the tailings from a Colombian coal preparation plant. The plant utilizes a dense-medium cyclones and spirals circuit. The tailings contained material that was 63% finer than 14 mu m. Flotation tests were performed with and without coal ""promoters"" (diesel oil or kerosene) to evaluate the kinetics of flotation of coal. It was found that flotation rates were higher when no promoter was added. Different kinetic models were evaluated for the flotation of the coal from the tailings, and it was found that the best fitted model was the classical first-order model.

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Fruit-set in tomato (Solanum lycopersicum) depends on gibberellins and auxins (GAs). Here, we show, using the cv MicroTom, that application of N-1-naphthylphthalamic acid (NPA; an inhibitor of auxin transport) to unpollinated ovaries induced parthenocarpic fruit-set, associated with an increase of indole-3-acetic acid (IAA) content, and that this effect was negated by paclobutrazol (an inhibitor of GA biosynthesis). NPA-induced ovaries contained higher content of GA(1) (an active GA) and transcripts of GA biosynthetic genes (SlCPS, SlGA20ox1, and -2). Interestingly, application of NPA to pollinated ovaries prevented their growth, potentially due to supraoptimal IAA accumulation. Plant decapitation and inhibition of auxin transport by NPA from the apical shoot also induced parthenocarpic fruit growth of unpollinated ovaries. Application of IAA to the severed stump negated the plant decapitation effect, indicating that the apical shoot prevents unpollinated ovary growth through IAA transport. Parthenocarpic fruit growth induced by plant decapitation was associated with high levels of GA(1) and was counteracted by paclobutrazol treatment. Plant decapitation also produced changes in transcript levels of genes encoding enzymes of GA biosynthesis (SlCPS and SlGA20ox1) in the ovary, quite similar to those found in NPA-induced fruits. All these results suggest that auxin can have opposing effects on fruit-set, either inducing (when accumulated in the ovary) or repressing (when transported from the apical shoot) that process, and that GAs act as mediators in both cases. The effect of NPA application and decapitation on fruit-set induction was also observed in MicroTom lines bearing introgressed DWARF and SELF-PRUNING wild-type alleles.

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Survival models involving frailties are commonly applied in studies where correlated event time data arise due to natural or artificial clustering. In this paper we present an application of such models in the animal breeding field. Specifically, a mixed survival model with a multivariate correlated frailty term is proposed for the analysis of data from over 3611 Brazilian Nellore cattle. The primary aim is to evaluate parental genetic effects on the trait length in days that their progeny need to gain a commercially specified standard weight gain. This trait is not measured directly but can be estimated from growth data. Results point to the importance of genetic effects and suggest that these models constitute a valuable data analysis tool for beef cattle breeding.