978 resultados para open system


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Apresenta um panorama geral de cobertura da rede UNA-SUS pelo Brasil, mostrando as principais estatísticas obtidas pela UNA-SUS, como: dados de acesso e quantidade de recursos educacionais.

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The generation of bradykinin (BK; Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg) in blood and kallidin (Lys-BK) in tissues by the action of the kallikrein-kinin system has received little attention in non-mammalian vertebrates. In mammals, kallidin can be generated by the coronary endothelium and myocytes in response to ischemia, mediating cardioprotective events. The plasma of birds lacks two key components of the kallikrein-kinin system: the low molecular weight kininogen and a prekallikrein activator analogous to mammalian factor XII, but treatment with bovine plasma kallikrein generates ornitho-kinin [Thr6,Leu8]-BK. The possible cardioprotective effect of ornitho-kinin infusion was investigated in an anesthetized, open-chest chicken model of acute coronary occlusion. A branch of the left main coronary artery was reversibly ligated to produce ischemia followed by reperfusion, after which the degree of myocardial necrosis (infarct size as a percent of area at risk) was assessed by tetrazolium staining. The iv injection of a low dose of ornitho-kinin (4 µg/kg) reduced mean arterial pressure from 88 ± 12 to 42 ± 7 mmHg and increased heart rate from 335 ± 38 to 402 ± 45 bpm (N = 5). The size of the infarct was reduced by pretreatment with ornitho-kinin (500 µg/kg infused over a period of 5 min) from 35 ± 3 to 10 ± 2% of the area at risk. These results suggest that the physiological role of the kallikrein-kinin system is preserved in this animal model in spite of the absence of two key components, i.e., low molecular weight kininogen and factor XII.

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This article describes the design, implementation, and experiences with AcMus, an open and integrated software platform for room acoustics research, which comprises tools for measurement, analysis, and simulation of rooms for music listening and production. Through use of affordable hardware, such as laptops, consumer audio interfaces and microphones, the software allows evaluation of relevant acoustical parameters with stable and consistent results, thus providing valuable information in the diagnosis of acoustical problems, as well as the possibility of simulating modifications in the room through analytical models. The system is open-source and based on a flexible and extensible Java plug-in framework, allowing for cross-platform portability, accessibility and experimentation, thus fostering collaboration of users, developers and researchers in the field of room acoustics.

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The endocannabinoid system is involved in the control of many physiological functions, including the control of emotional states. In rodents, previous exposure to an open field increases the anxiety-like behavior in the elevated plus-maze. Anxiolytic-like effects of pharmacological compounds that increase endocannabinoid levels have been well documented. However, these effects are more evident in animals with high anxiety levels. Several studies have described characteristic inverted U-shaped dose-response effects of drugs that modulate the endocannabinoid levels. However, there are no studies showing the effects of different doses of exogenous anandamide, an endocannabinoid, in animal models of anxiety. Thus, in the present study, we determined the dose-response effects of exogenous anandamide at doses of 0.01, 0.1, and 1.0 mg/kg in C57BL/6 mice (N = 10/group) sequentially submitted to the open field and elevated plus-maze. Anandamide was diluted in 0.9% saline, ethyl alcohol, Emulphor® (18:1:1) and administered ip (0.1 mL/10 g body weight); control animals received the same volume of anandamide vehicle. Anandamide at the dose of 0.1 mg/kg (but not of 0.01 or 1 mg/kg) increased (P < 0.05) the time spent and the distance covered in the central zone of the open field, as well as the exploration of the open arms of the elevated plus-maze. Thus, exogenous anandamide, like pharmacological compounds that increase endocannabinoid levels, promoted a characteristic inverted U-shaped dose-response effect in animal models of anxiety. Furthermore, anandamide (0.1 mg/kg) induced an anxiolytic-like effect in the elevated plus-maze (P < 0.05) after exposing the animals to the open field test.

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The brief interaction of precipitation with a forest canopy can create a high spatial variability of both throughfall and solute deposition. We hypothesized that (i) the variability in natural forest systems is high but depends on system-inherent stability, (ii) the spatial variability of solute deposition shows seasonal dynamics depending on the increase in rainfall frequency, and (iii) spatial patterns persist only in the short-term. The study area in the north-western Brazilian state of Rondonia is subject to a climate with a distinct wet and dry season. We collected rain and throughfall on an event basis during the early wet season (n = 14) and peak of the wet season (n = 14) and analyzed the samples for pH and concentrations of NH4+, Na+, K+, Ca2+ Mg2+,, Cl-, NO3-, SO42- and DOC. The coefficient 3 4 cient of variation for throughfall based on both sampling intervals was 29%, which is at the lower end of values reported from other tropical forest sites, but which is higher than in most temperate forests. Coefficients of variation of solute deposition ranged from 29% to 52%. This heterogeneity of solute deposition is neither particularly high nor particularly tow compared with a range of tropical and temperate forest ecosystems. We observed an increase in solute deposition variability with the progressing wet season, which was explained by a negative correlation between heterogeneity of solute deposition and antecedent dry period. The temporal stability of throughfall. patterns was Low during the early wet season, but gained in stability as the wet season progressed. We suggest that rapid plant growth at the beginning of the rainy season is responsible for the lower stability, whereas less vegetative activity during the later rainy season might favor the higher persistence of ""hot"" and ""cold"" spots of throughfall. quantities. The relatively high stability of throughfall patterns during later stages of the wet season may influence processes at the forest floor and in the soil. Solute deposition patterns showed less clear trends but all patterns displayed a short-term stability only. The weak stability of those patterns is apt to impede the formation of solute deposition -induced biochemical microhabitats in the soil. (C) 2008 Elsevier B.V. All rights reserved.

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Support for interoperability and interchangeability of software components which are part of a fieldbus automation system relies on the definition of open architectures, most of them involving proprietary technologies. Concurrently, standard, open and non-proprietary technologies, such as XML, SOAP, Web Services and the like, have greatly evolved and been diffused in the computing area. This article presents a FOUNDATION fieldbus (TM) device description technology named Open-EDD, based on XML and other related technologies (XLST, DOM using Xerces implementation, OO, XMIL Schema), proposing an open and nonproprietary alternative to the EDD (Electronic Device Description). This initial proposal includes defining Open-EDDML as the programming language of the technology in the FOUNDATION fieldbus (TM) protocol, implementing a compiler and a parser, and finally, integrating and testing the new technology using field devices and a commercial fieldbus configurator. This study attests that this new technology is feasible and can be applied to other configurators or HMI applications used in fieldbus automation systems. (c) 2008 Elsevier B.V. All rights reserved.

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During the last few years, the evolution of fieldbus and computers networks allowed the integration of different communication systems involving both production single cells and production cells, as well as other systems for business intelligence, supervision and control. Several well-adopted communication technologies exist today for public and non-public networks. Since most of the industrial applications are time-critical, the requirements of communication systems for remote control differ from common applications for computer networks accessing the Internet, such as Web, e-mail and file transfer. The solution proposed and outlined in this work is called CyberOPC. It includes the study and the implementation of a new open communication system for remote control of industrial CNC machines, making the transmission delay for time-critical control data shorter than other OPC-based solutions, and fulfilling cyber security requirements.

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The theoretical and experimental open-circuit voltage optimizations of a simple fabrication process of silicon solar cells n(+)p with rear passivation are presented. The theoretical results were obtained by using an in-house developed program, including the light trapping effect and metal-grid optimization. On the other hand, the experimental steps were monitored by the photoconductive decay technique. The starting materials presented thickness of about 300 pm and resistivities: FZ (0.5 Omega cm), Cz-type 1 (2.5 Omega cm) and Cz-type 2 (3.3 Omega cm). The Gaussian profile emitters were optimized with sheet resistance between 55 Omega/sq and 100 Omega/sq, and approximately 2.0 mu m thickness in accordance to the theoretical results. Excellent implied open-circuit voltages of 670.8 mV, 652.5 mV and 662.6 mV, for FZ, Cz-type 1 and Cz-type 2 silicon wafers, respectively, could be associated to the measured lifetimes that represents solar cell efficiency up to 20% if a low cost anti-reflection coating system, composed by random pyramids and SiO(2) layer, is considered even for typical Cz silicon. (C) 2009 Elsevier Ltd. All rights reserved.

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A new digital computer mock circulatory system has been developed in order to replicate the physiologic and pathophysiologic characteristics of the human cardiovascular system. The computer performs the acquisition of pressure, flow, and temperature in an open loop system. A computer program has been developed in Labview programing environment to evaluate all these physical parameters. The acquisition system was composed of pressure, flow, and temperature sensors and also signal conditioning modules. In this study, some results of flow, cardiac frequencies, pressures, and temperature were evaluated according to physiologic ventricular states. The results were compared with literature data. In further works, performance investigations will be conducted on a ventricular assist device and endoprosthesis. Also, this device should allow for evaluation of several kinds of vascular diseases.

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The University of Queensland, Australia has developed Fez, a world-leading user-interface and management system for Fedora-based institutional repositories, which bridges the gap between a repository and users. Christiaan Kortekaas, Andrew Bennett and Keith Webster will review this open source software that gives institutions the power to create a comprehensive repository solution without the hassle..

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Almost all clinical magnetic resonance imaging systems are based on circular cross-section magnets. Recent advances in elliptical cross-section RF probe and gradient coil hardware raise the question of the possibility of using elliptical cross-section magnet systems, This paper presents a methodology for calculating rapidly the magnetic fields generated by a multi-turn coil of elliptical cross-section and incorporates this in a stochastic optimization method for magnet design, An open magnet system of elliptical cross-section is designed that both reduces the claustrophobia for the patients and allows ready access by attending physicians, The magnet system is optimized for paediatric use, The coil geometry produced by the optimization method has several novel features.

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A general graded reflection equation algebra is proposed and the corresponding boundary quantum inverse scattering method is formulated. The formalism is applicable to all boundary lattice systems where an invertible R-matrix exists. As an application, the integrable open-boundary conditions for the q-deformed supersymmetric U model of strongly correlated electrons are investigated. The diagonal boundary K-matrices are found and a class of integrable boundary terms are determined. The boundary system is solved by means of the coordinate space Bethe ansatz technique and the Bethe ansatz equations are derived. As a sideline, it is shown that all R-matrices associated with a quantum affine superalgebra enjoy the crossing-unitarity property. (C) 1998 Elsevier Science B.V.

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Confocal imaging of impermeant fluorescent dyes trapped in the tubular (t-) system of skeletal muscle fibres of rat and cane toad was used to examine changes in the morphology of the t-system upon mechanical skinning, the time course of dye loss from the sealed t-systern in mechanically skinned fibres and the influence of rapid application and removal of glycerol on the morphology of the sealed t-system. In contrast to intact fibres, which have a t-systern open to the outside, the sealed t-systern of toad mechanically skinned fibres consistently displayed local swellings (vesicles). The occurrence of vesicles in the sealed t-system of rat-skinned fibres was infrequent. Application and removal of 200-400 mM glycerol to the sealed t-system did not produce any obvious changes in its morphology. The dyes fluo-3, fura-2 and Oregon green 488 were lost from the sealed t-system of toad fibres at different rates suggesting that the mechanism of organic anion transport across the tubular wall was not by indiscriminate bulk transport. The rate of fluo-3 and fura-2 loss from the sealed t-system of rat fibres was greater in rat than in toad fibres and could be explained by differences in surface area: volume ratio of the t-system in the two fibre types. Based on the results presented here and on other results from this laboratory, an explanation is given for the formation of numerous vesicles in toad-skinned fibres and lack of vesicle formation in rat-skinned fibres. This explanation can also help with better understanding the mechanism responsible for vacuole formation in intact fibres. (C) 2002 Elsevier Science Ltd. All rights reserved.

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Epidural motor cortex stimulation (MCS) has been used for treating patients with neuropathic pain resistant to other therapeutic approaches. Experimental evidence suggests that the motor cortex is also involved in the modulation of normal nociceptive response, but the underlying mechanisms of pain control have not been clarified yet. The aim of this study was to investigate the effects of epidural electrical MCS on the nociceptive threshold of naive rats. Electrodes were placed on epidural motor cortex, over the hind paw area, according to the functional mapping accomplished in this study. Nociceptive threshold and general activity were evaluated under 15-min electrical stimulating sessions. When rats were evaluated by the paw pressure test, MCS induced selective antinociception in the paw contralateral to the stimulated cortex, but no changes were noticed in the ipsilateral paw. When the nociceptive test was repeated 15 min after cessation of electrical stimulation, the nociceptive threshold returned to basal levels. On the other hand, no changes in the nociceptive threshold were observed in rats evaluated by the tail-flick test. Additionally, no behavioral or motor impairment were noticed in the course of stimulation session at the open-field test. Stimulation of posterior parietal or somatosensory cortices did not elicit any changes in the general activity or nociceptive response. Opioid receptors blockade by naloxone abolished the increase in nociceptive threshold induced by MCS. Data shown herein demonstrate that epidural electrical MCS elicits a substantial and selective antinociceptive effect, which is mediated by opioids. (C) 2008 Elsevier B.V. All rights reserved.

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The longest open reading frame of PKHD1 (polycystic kidney and hepatic disease 1), the autosomal recessive polycystic kidney disease (ARPKD) gene, encodes a single-pass, integral membrane protein named polyductin or fibrocystin. A fusion protein comprising its intracellular C-terminus, FP2, was previously used to raise a polyclonal antiserum shown to detect polyductin in several human tissues, including liver. In the current study, we aimed to investigate by immunohistochemistry the detailed polyductin localization pattern in normal (ductal plate [DP], remodelling ductal plate [RDP], remodelled bile ducts) and abnormal development of the primitive intrahepatic biliary system, known as ductal plate malformation (DPM). This work also included the characterization of polyductin expression profile in various histological forms of neonatal and infantile cholestasis, and in cholangiocellular carcinoma (CCC) and hepatocellular carcinoma (HCC). We detected polyductin expression in the intrahepatic biliary system during the DP and the RDP stages as well as in DPM. No specific staining was found at the stage of remodelled bile ducts. Polyductin was also detected in liver biopsies with neonatal cholestasis, including mainly biliary atresia and neonatal hepatitis with ductular reaction as well as congenital hepatic fibrosis. In addition, polyductin was present in CCC, whereas it was absent in HCC. Polyductin was also co-localized in some DP cells together with oval stem cell markers. These results represent the first systematic study of polyductin expression in human pathologies associated with abnormal development of intrahepatic biliary tree, and support the following conclusions: (i) polyductin expression mirrors developmental properties of the primitive intrahepatic biliary system; (ii) polyductin is re-expressed in pathological conditions associated with DPM and (iii) polyductin might be a potential marker to distinguish CCC from HCC.