960 resultados para FUNCTIONAL DATA


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ABSTRACT Microphysical and thermodynamical features of two tropical systems, namely Hurricane Ivan and Typhoon Conson, and one sub-tropical, Catarina, have been analyzed based on space-born radar PR measurements available on the TRMM satellite. The procedure to classify the reflectivity profiles followed the Heymsfield et al (2000) and Steiner et al (1995) methodologies. The water and ice content have been calculated using a relationship obtained with data of the surface SPOL radar and PR in Rondonia State in Brazil. The diabatic heating rate due to latent heat release has been estimated using the methodology developed by Tao et al (1990). A more detailed analysis has been performed for Hurricane Catarina, the first of its kind in South Atlantic. High water content mean value has been found in Conson and Ivan at low levels and close to their centers. Results indicate that hurricane Catarina was shallower than the other two systems, with less water and the water was concentrated closer to its center. The mean ice content in Catarina was about 0.05 g kg-1 while in Conson it was 0.06 g kg-1 and in Ivan 0.08 g kg-1. Conson and Ivan had water content up to 0.3 g kg-1 above the 0ºC layer, while Catarina had less than 0.15 g kg-1. The latent heat released by Catarina showed to be very similar to the other two systems, except in the regions closer to the center.

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Phytoplankton may function as a "sensor" of changes in aquatic environment and responds rapidly to such changes. In freshwaters, coexistence of species that have similar ecological requirements and show the same environmental requirements frequently occurs; such species groups are named functional groups. The use of phytoplankton functional groups to evaluate these changes has proven to be very useful and effective. Thus, the aim of this study was to evaluate the occurrence of functional groups of phytoplankton in two reservoirs (Billings and Guarapiranga) that supply water to millions of people in São Paulo city Metropolitan Area, southeastern Brazil. Surface water samples were collected monthly and physical, chemical and biological (quantitative and qualitative analyses of the phytoplankton) were performed. The highest biovolume (mm³.L-1) of the descriptor species and functional groups were represented respectively by Anabaena circinalis Rabenh. (H1), Microcystis aeruginosa (Kützing) Kützing (L M/M) and Mougeotia sp. (T) in the Guarapiranga reservoir and Cylindrospermopsis raciborskii (Wolosz.) Seen. and Subba Raju (S N), Microcystis aeruginosa and M. panniformis Komárek et al. (L M/M), Planktothrix agardhii (Gom.) Anagn. and Komárek and P. cf. clathrata (Skuja) Anagn. and Komárek (S1) in the Billings reservoir. The environmental factors that most influenced the phytoplankton dynamics were water temperature, euphotic zone, turbidity, conductivity, pH, dissolved oxygen, nitrate and total phosphorous.

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Spastic paraplegia, optic atrophy, and neuropathy (SPOAN) is an autosomal recessive complicated form of hereditary spastic paraplegia, which is clinically defined by congenital optic atrophy, infancy-onset progressive spastic paraplegia and peripheral neuropathy. In this study, which included 61 individuals (age 5-72 years, 42 females) affected by SPOAN, a comprehensive motor and functional evaluation was performed, using modified Barthel index, modified Ashworth scale, hand grip strength measured with a hydraulic dynamometer and two hereditary spastic paraplegia scales. Modified Barthel index, which evaluate several functional aspects, was more sensitive to disclose disease progression than the spastic paraplegia scales. Spasticity showed a bimodal distribution, with both grades 1 (minimum) and 4 (maximum). Hand grip strength showed a moderate inverse correlation with age. Combination of early onset spastic paraplegia and progressive polyneuropathy make SPOAN disability overwhelming.

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Lepidocharax, new genus, and Lepidocharax diamantina and L. burnsi new species from eastern Brazil are described herein. Lepidocharax is considered a monophyletic genus of the Stevardiinae and can be distinguished from the other members of this subfamily except Planaltina, Pseudocorynopoma, and Xenurobrycon by having the dorsal-fin origin vertically aligned with the anal-fin origin, vs. dorsal fin origin anterior or posterior to anal-fin origin. Additionally the new genus can be distinguished from those three genera by not having the scales extending over the ventral caudal-fin lobe modified to form the dorsal border of the pheromone pouch organ or to represent a pouch scale in sexually mature males. In this paper, we describe these two recently discovered species and the ultrastructure of their spermatozoa.

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During the exploration and mapping of new caves in Serra do Ramalho karst area, southern Bahia state, cavers from the Grupo Bambuí de Pesquisas Espeleológicas - GBPE (Belo Horizonte) noticed the presence of troglomorphic catfishes (species with reduced eyes and/or melanic pigmentation), which we intensively investigated with regards to their ecology and behavior since 2005. Non-troglomorphic fishes regularly found in the studied caves were included in this investigation. We present here data on the natural history of two troglobitic (exclusively subterranean troglomorphic species) fishes - Rhamdia enfurnada Bichuette & Trajano, 2005 (Heptapteridae; Gruna do Enfurnado) and Trichomycterus undescribed species (Trichomycteridae; Lapa dos Peixes and Gruna da Água Clara), and non-troglomorphic Hoplias cf. malabaricus, probably a troglophile (able to form populations both in epigean and subterranean habitats) in the Gruna do Enfurnado, and Pimelodella sp., a species with a sink population in the Lapa dos Peixes.

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Stress is triggered by numerous unexpected environmental, social or pathological stimuli occurring during the life of animals, including humans, which determine changes in all of their systems. Although acute stress is essential for survival, chronic, long-lasting stress can be detrimental. In this review, we present data supporting the hypothesis that stress-related events are characterized by modifications of oxidative/nitrosative pathways in the brain in response to the activation of inflammatory mediators. Recent findings indicate a key role for nitric oxide (NO) and an excess of pro-oxidants in various brain areas as responsible for both neuronal functional impairment and structural damage. Similarly, cyclooxygenase-2 (COX-2), another known source of oxidants, may account for stress-induced brain damage. Interestingly, some of the COX-2-derived mediators, such as the prostaglandin 15d-PGJ2 and its peroxisome proliferator-activated nuclear receptor PPARγ, are activated in the brain in response to stress, constituting a possible endogenous anti-inflammatory mechanism of defense against excessive inflammation. The stress-induced activation of both biochemical pathways depends on the activation of the N-methyl-D-aspartate (NMDA) glutamate receptor and on the activation of the transcription factor nuclear factor kappa B (NFκB). In the case of inducible NO synthase (iNOS), release of the cytokine TNF-α also accounts for its expression. Different pharmacological strategies directed towards different sites in iNOS or COX-2 pathways have been shown to be neuroprotective in stress-induced brain damage: NMDA receptor blockers, inhibitors of TNF-α activation and release, inhibitors of NFκB, specific inhibitors of iNOS and COX-2 activities and PPARγ agonists. This article reviews recent contributions to this area addressing possible new pharmacological targets for the treatment of stress-induced neuropsychiatric disorders.

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In this study, we evaluated the expression of the Zenk protein within the nucleus taeniae of the pigeon’s amygdala (TnA) after training in a classical aversive conditioning, in order to improve our understanding of its functional role in birds. Thirty-two 18-month-old adult male pigeons (Columba livia), weighing on average 350 g, were trained under different conditions: with tone-shock associations (experimental group; EG); with shock-alone presentations (shock group; SG); with tone-alone presentations (tone group; TG); with exposure to the training chamber without stimulation (context group; CG), and with daily handling (naive group; NG). The number of immunoreactive nuclei was counted in the whole TnA region and is reported as density of Zenk-positive nuclei. This density of Zenk-positive cells in the TnA was significantly greater for the EG, SG and TG than for the CG and NG (P < 0.05). The data indicate an expression of Zenk in the TnA that was driven by experience, supporting the role of this brain area as a critical element for neural processing of aversive stimuli as well as meaningful novel stimuli.

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Neurotransmitters are also involved in functions other than conventional signal transfer between nerve cells, such as development, plasticity, neurodegeneration, and neuroprotection. For example, there is a considerable amount of data indicating developmental roles for the glutamatergic, cholinergic, dopaminergic, GABA-ergic, and ATP/adenosine systems. In this review, we discuss the existing literature on these "new" functions of neurotransmitters in relation to some unconventional neurotransmitters, such as the endocannabinoids and nitric oxide. Data indicating both transcriptional and post-transcriptional modulation of endocannabinoid and nitrinergic systems after neural lesions are discussed in relation to the non-conventional roles of these neurotransmitters. Knowledge of the roles of neurotransmitters in brain functions other than information transfer is critical for a more complete understanding of the functional organization of the brain and to provide more opportunities for the development of therapeutical tools aimed at minimizing neuronal death.

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FUNDAMENTO: A ressuscitação de parada cardíaca pode apresentar disfunção miocárdica determinada pelo tempo da isquemia, e a inibição da enzima conversora de angiotensina (ECA) pode reduzir a disfunção cardíaca durante a reperfusão. OBJETIVO: Investigar os efeitos da angiotensina-I e diferentes períodos de isquemia na recuperação funcional em corações de ratos isolados. MÉTODOS: Os corações isolados de ratos Wistar (n = 45; 250-300 g) foram submetidos a diferentes períodos de isquemia global (20, 25 ou 30 min) e reperfundidos (30 min) com o tampão Krebs-Henseleit, ou com a adição de 400 nmol/L de angiotensina-I, ou com 400 nmol/L de angiotensina-I + 100 µmol/L de captopril durante o período de reperfusão. RESULTADOS: A derivada positiva máxima de pressão (+dP/dt max) e o produto frequência-pressão foram reduzidos nos corações expostos à isquemia de 25 min (~ 73%) e à isquemia de 30 min (~ 80%) vs. isquemia de 20 min. A pressão diastólica final do ventrículo esquerdo (PDFVE) e a pressão de perfusão (PP) foram aumentadas nos corações expostos à isquemia de 25 min (5,5 e 1,08 vezes, respectivamente) e à isquemia de 30 min (6 e 1,10 vezes, respectivamente) vs. isquemia de 20 min. A angiotensina-I ocasionou uma diminuição no +dP/dt max e no produto frequência-pressão (~ 85-94%) em todos os períodos de isquemia e um aumento na PDFVE e na PP (6,9 e 1,25 vezes, respectivamente) apenas na isquemia de 20 min. O captopril foi capaz de reverter parcial ou completamente os efeitos da angiotensina-I na recuperação funcional nas isquemias de 20 e 25 min CONCLUSÃO: Os dados sugerem que a angiotensina-II participa direta ou indiretamente no dano pós-isquêmico e que a capacidade de um inibidor da ECA atenuar esse dano depende do tempo de isquemia.

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INTRODUÇÃO: A constipação crônica é doença comum na infância, ocorrendo em 5 a 10% dos pacientes pediátricos, considerada a segunda maior causa de procura nos consultórios de pediatria, sendo a encoprese decorrente de constipação grave associada à impactação fecal no reto. Dentre os exames diagnósticos, a manometria anal é utilizada para a avaliação de pacientes com distúrbios funcionais, como a constipação intestinal e a incontinência fecal, em alguns serviços para a avaliação de pacientes com encoprese, pois pode trazer informações sobre o mecanismo evacuatório e possíveis lesões esfincterianas anais. OBJETIVO: Verificar alterações manométricas em pacientes com encoprese. MÉTODOS: Foi realizado estudo de 40 manometrias anais de crianças constipadas com encoprese (G1) e 12 crianças constipados sem encoprese (G2). Foram obtidos os seguintes dados: pressões de repouso, contração e evacuação do canal anal e ampola retal, ponto de maior pressão, reflexo inibitório anal e sensibilidade retal. As manometrias foram realizadas com o aparelho Alacer de perfusão com 8 canais. RESULTADOS: Não foram encontradas diferenças nas pressões de repouso, contração e evacuação do canal anal entre os grupos. Chamou-nos a atenção a ausência de necessidade de maior volume retal para desencadear o reflexo inibitório anal. Não houve diferença da incidência de anismus entre os dois grupos, demonstrando que não se trata de fator importante na manutenção da encoprese, mas sim da constipação. CONCLUSÃO: Não houve necessidade de maior volume para desencadear o reflexo inibitório anal. O anismus não foi diferente entre os dois grupos, não sendo importante na manutenção da encoprese.

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Geographic Data Warehouses (GDW) are one of the main technologies used in decision-making processes and spatial analysis, and the literature proposes several conceptual and logical data models for GDW. However, little effort has been focused on studying how spatial data redundancy affects SOLAP (Spatial On-Line Analytical Processing) query performance over GDW. In this paper, we investigate this issue. Firstly, we compare redundant and non-redundant GDW schemas and conclude that redundancy is related to high performance losses. We also analyze the issue of indexing, aiming at improving SOLAP query performance on a redundant GDW. Comparisons of the SB-index approach, the star-join aided by R-tree and the star-join aided by GiST indicate that the SB-index significantly improves the elapsed time in query processing from 25% up to 99% with regard to SOLAP queries defined over the spatial predicates of intersection, enclosure and containment and applied to roll-up and drill-down operations. We also investigate the impact of the increase in data volume on the performance. The increase did not impair the performance of the SB-index, which highly improved the elapsed time in query processing. Performance tests also show that the SB-index is far more compact than the star-join, requiring only a small fraction of at most 0.20% of the volume. Moreover, we propose a specific enhancement of the SB-index to deal with spatial data redundancy. This enhancement improved performance from 80 to 91% for redundant GDW schemas.

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Due to the imprecise nature of biological experiments, biological data is often characterized by the presence of redundant and noisy data. This may be due to errors that occurred during data collection, such as contaminations in laboratorial samples. It is the case of gene expression data, where the equipments and tools currently used frequently produce noisy biological data. Machine Learning algorithms have been successfully used in gene expression data analysis. Although many Machine Learning algorithms can deal with noise, detecting and removing noisy instances from the training data set can help the induction of the target hypothesis. This paper evaluates the use of distance-based pre-processing techniques for noise detection in gene expression data classification problems. This evaluation analyzes the effectiveness of the techniques investigated in removing noisy data, measured by the accuracy obtained by different Machine Learning classifiers over the pre-processed data.

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The n→π* absorption transition of formaldehyde in water is analyzed using combined and sequential classical Monte Carlo (MC) simulations and quantum mechanics (QM) calculations. MC simulations generate the liquid solute-solvent structures for subsequent QM calculations. Using time-dependent density functional theory in a localized set of gaussian basis functions (TD-DFT/6-311++G(d,p)) calculations are made on statistically relevant configurations to obtain the average solvatochromic shift. All results presented here use the electrostatic embedding of the solvent. The statistically converged average result obtained of 2300 cm-1 is compared to previous theoretical results available. Analysis is made of the effective dipole moment of the hydrogen-bonded shell and how it could be held responsible for the polarization of the solvent molecules in the outer solvation shells.

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OBJECTIVE: To estimate the spatial intensity of urban violence events using wavelet-based methods and emergency room data. METHODS: Information on victims attended at the emergency room of a public hospital in the city of São Paulo, Southeastern Brazil, from January 1, 2002 to January 11, 2003 were obtained from hospital records. The spatial distribution of 3,540 events was recorded and a uniform random procedure was used to allocate records with incomplete addresses. Point processes and wavelet analysis technique were used to estimate the spatial intensity, defined as the expected number of events by unit area. RESULTS: Of all georeferenced points, 59% were accidents and 40% were assaults. There is a non-homogeneous spatial distribution of the events with high concentration in two districts and three large avenues in the southern area of the city of São Paulo. CONCLUSIONS: Hospital records combined with methodological tools to estimate intensity of events are useful to study urban violence. The wavelet analysis is useful in the computation of the expected number of events and their respective confidence bands for any sub-region and, consequently, in the specification of risk estimates that could be used in decision-making processes for public policies.

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The aim of this study was to test the hypothesis of differences in performance including differences in ST-T wave changes between healthy men and women submitted to an exercise stress test. Two hundred (45.4%) men and 241 (54.6%) women (mean age: 38.7 ± 11.0 years) were submitted to an exercise stress test. Physiologic and electrocardiographic variables were compared by the Student t-test and the chi-square test. To test the hypothesis of differences in ST-segment changes, data were ranked with functional models based on weighted least squares. To evaluate the influence of gender and age on the diagnosis of ST-segment abnormality, a logistic model was adjusted; P < 0.05 was considered to be significant. Rate-pressure product, duration of exercise and estimated functional capacity were higher in men (P < 0.05). Sixteen (6.7%) women and 9 (4.5%) men demonstrated ST-segment upslope ≥0.15 mV or downslope ≥0.10 mV; the difference was not statistically significant. Age increase of one year added 4% to the chance of upsloping of segment ST ≥0.15 mV or downsloping of segment ST ≥0.1 mV (P = 0.03; risk ratio = 1.040, 95% confidence interval (CI) = 1.002-1.080). Heart rate recovery was higher in women (P < 0.05). The chance of women showing an increase of systolic blood pressure ≤30 mmHg was 85% higher (P = 0.01; risk ratio = 1.85, 95%CI = 1.1-3.05). No significant difference in the frequency of ST-T wave changes was observed between men and women. Other differences may be related to different physical conditioning.