906 resultados para automatically generated meta classifiers with large levels


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Selenium (Se) intake is generally from food, whose Se content depends on soil Se and plant accumulation. For humans, adequate Se intake is essential for several selenoenzymes. In the Lower Tapajos region of the Brazilian Amazon, Se status is elevated with large inter-community variability. Se intake in this region, where Hg exposure is among the highest in the world, may be important to counteract mercury (Hg) toxicity. The present study was conducted in 2006 with 155 persons from four communities of the Lower Tapajos. The objectives were: i) to evaluate Se content in their typical diet and drinking water; ii) to compare food Se concentrations with respect to geographic location; and iii) to examine the contribution of consumption of different food items to blood Se. More than 400 local foods and 40 drinking water samples were collected. Participants responded to an interview-administered food frequency questionnaire and provided blood samples. Food, water and blood Se levels were assessed by ICP-MS. Since Brazil nuts may also contain significant levels of barium (Ba) and strontium (Sr), these elements were likewise analyzed in nuts. The highest Se concentrations were found in Brazil nuts, but concentrations were highly variable (median: 13.9 mu g/g; range: 0.4-158.4 mu g/g). Chicken, game meat, eggs and beef also contained considerable levels of Se, with median concentrations from 0.3 to 1.4 mu g/g. There was no particular geographic distribution of food Se. Se concentration in drinking water was very low (<1.4 mu g/L). Blood Se covered a (103-1500 mu g/L), and was positively related to regular consumption of Brazil nuts, domestic chicken and game meat. Brazil nuts were found to contain highly variable and often very high concentrations of Ba (88.0 mu g/g, 1.9-1437 mu g/g) and Sr (38.7 mu g/g, 3.3-173 mu g/g). Further studies should address multiple nutrient/toxic interactions in the diet and related effects on health. (c) 2010 Elsevier B.V. All rights reserved.

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We have shown previously that melanoma cells in culture release heavy-chain ferritin (H-Ferritin) into supernatants and that this is responsible for the suppression of responses of peripheral blood lymphocytes stimulated by anti-CD3. These effects were mediated by activation of regulatory T cells to produce interleukin (IL)-10. In the present study, we examined whether a similar relation might exist between levels of H-Ferritin and activation of regulatory T cells in patients with melanoma. Ferritin levels were evaluated by ELISA and regulatory T-cell numbers were assessed by three-color flow cytometry to identify CD4(+) CD25(+) CD69(-) T cells. CD69 positive cells were excluded to avoid inclusion of normal activated CD4, CD25 expressing T cells. Measurements of H- and light-chain (L)-Ferritin by ELISA revealed that H- but not L-Ferritin was elevated in the circulation of melanoma patients. In addition, these studies revealed a marked increase in the number of CD4+ CD25+ CD69- T cells in such patients, compared with age-matched controls. The ratio of H-Ferritin:L-Ferritin correlated with the levels of regulatory T cells consistent with a causal relation between unbound H-Ferritin levels and the activation of regulatory T cells. H-Ferritin or regulatory T cells did not, however, correlate with the stage of the melanoma. These results provide evidence for the importance of H-Ferritin in the induction of regulatory T cells in patients with melanoma and provide additional insight into the suppression of immune responses in such patients.

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Preoperative progressive pneumoperitoneum (PPP) is a safe and effective procedure in the treatment of large incisional hernia (size > 10 cm in width or length) with loss of domain (LIHLD). There is no consensus in the literature on the amount of gas that must be insufflated in a PPP program or even how long it should be maintained. We describe a technique for calculating the hernia sac volume (HSV) and abdominal cavity volume (ACV) based on abdominal computerized tomography (ACT) scanning that eliminates the need for subjective criteria for inclusion in a PPP program and shows the amount of gas that must be insufflated into the abdominal cavity in the PPP program. Our technique is indicated for all patients with large or recurrent incisional hernias evaluated by a senior surgeon with suspected LIHLD. We reviewed our experience from 2001 to 2008 of 23 consecutive hernia surgical procedures of LIHLD undergoing preoperative evaluation with CT scanning and PPP. An ACT was required in all patients with suspected LIHLD in order to determine HSV and ACV. The PPP was performed only if the volume ratio HSV/ACV (VR = HSV/ACV) was a parts per thousand yen25% (VR a parts per thousand yen 25%). We have performed this procedure on 23 patients, with a mean age of 55.6 years (range 31-83). There were 16 women and 7 men with an average age of 55.6 years (range 31-83), and a mean BMI of 38.5 kg/m(2) (range 23-55.2). Almost all patients (21 of 23 patients-91.30%) were overweight; 43.5% (10 patients) were severely obese (obese class III). The mean calculated volumes for ACV and HSV were 9,410 ml (range 6,060-19,230 ml) and 4,500 ml (range 1,850-6,600 ml), respectively. The PPP is performed by permanent catheter placed in a minor surgical procedure. The total amount of CO(2) insufflated ranged from 2,000 to 7,000 ml (mean 4,000 ml). Patients required a mean of 10 PPP sessions (range 4-18) to achieve the desired volume of gas (that is the same volume that was calculated for the hernia sac). Since PPP sessions were performed once a day, 4-18 days were needed for preoperative preparation with PPP. The mean VR was 36% (ranged from 26 to 73%). We conclude that ACT provides objective data for volume calculation of both hernia sac and abdominal cavity and also for estimation of the volume of gas that should be insufflated into the abdominal cavity in PPP.

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This study aimed to quantify the efficiency and smoothness of voluntary movement in Huntington's disease (HD) by the use of a graphics tablet that permits analysis of movement profiles. In particular, we aimed to ascertain whether a concurrent task (digit span) would affect the kinematics of goal-directed movements. Twelve patients with HD and their matched controls performed 12 vertical zig-zag movements, with both left and right hands (with and without the concurrent task), to large or small circular targets over long or short extents. The concurrent task was associated with shorter movement times and reduced right-hand superiority. Patients with HD were overall slower, especially with long strokes, and had similar peak velocities for both small and large targets, so that controls could better accommodate differences in target size. Patients with HD spent more time decelerating, especially with small targets, whereas controls allocated more nearly equal proportions of time to the acceleration and deceleration phases of movement, especially with large targets. Short strokes were generally less force inefficient than were long strokes, especially so for either hand in either group in the absence of the concurrent task, and for the right hand in its presence. With the concurrent task, however, the left hand's behavior changed differentially for the two groups; for patients with HD, it became more force efficient with short strokes and even less efficient with long strokes, whereas for controls, it became more efficient with long strokes. Controls may be able to divert attention away from the inferior left hand, increasing its automaticity, whereas patients with HD, because of disease, may be forced to engage even further online visual control under the demands of a concurrent task. Patients with HD may perhaps become increasingly reliant on terminal visual guidance, which indicates an impairment in constructing and refining an internal representation of the movement necessary for its. effective execution. Basal ganglia dysfunction may impair the ability to use internally generated cues to guide movement.

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Background Meta-analysis is increasingly being employed as a screening procedure in large-scale association studies to select promising variants for follow-up studies. However, standard methods for meta-analysis require the assumption of an underlying genetic model, which is typically unknown a priori. This drawback can introduce model misspecifications, causing power to be suboptimal, or the evaluation of multiple genetic models, which augments the number of false-positive associations, ultimately leading to waste of resources with fruitless replication studies. We used simulated meta-analyses of large genetic association studies to investigate naive strategies of genetic model specification to optimize screenings of genome-wide meta-analysis signals for further replication. Methods Different methods, meta-analytical models and strategies were compared in terms of power and type-I error. Simulations were carried out for a binary trait in a wide range of true genetic models, genome-wide thresholds, minor allele frequencies (MAFs), odds ratios and between-study heterogeneity (tau(2)). Results Among the investigated strategies, a simple Bonferroni-corrected approach that fits both multiplicative and recessive models was found to be optimal in most examined scenarios, reducing the likelihood of false discoveries and enhancing power in scenarios with small MAFs either in the presence or in absence of heterogeneity. Nonetheless, this strategy is sensitive to tau(2) whenever the susceptibility allele is common (MAF epsilon 30%), resulting in an increased number of false-positive associations compared with an analysis that considers only the multiplicative model. Conclusion Invoking a simple Bonferroni adjustment and testing for both multiplicative and recessive models is fast and an optimal strategy in large meta-analysis-based screenings. However, care must be taken when examined variants are common, where specification of a multiplicative model alone may be preferable.

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Introduction: Body mass index (BMI) increase is an undesired effect associated with antipsychotics, and crucial for patients` global health and treatment compliance. We aimed to investigate the relation between BMI during olanzapine or halopericlol treatments and leptin, neuropeptide Y (NPY), adiponectin and lipid serum levels. Methods: In this 9-month, randomized and naturalist study, 34 male patients, 18 on olanzapine and 16 on haloperidol group were enrolled, all were under monotherapy. Patient outcome was evaluated with positive and negative syndrome scale (PANSS) at every 3-month period. In each visit, BMI, leptin, NPY, lipid, olanzapine or haloperidol levels were also monitored. Results and Discussion: Leptin levels positively correlated with BMI in olanzapine (r = 0.64, p < 0.001) and haloperidol (r = 0.73, p < 0.001) groups; only in olanzapine patients, the former also correlated with PANSS score (r = 0.54, p < 0.05). NPY levels negatively correlated with olanzapine levels (r = -0.65, p < 0.01). Adiponectin levels had not significantly varied. Conclusion: Antipsychotics probably interfere on leptin and NPY signalling ways and disturb these hormones in eating behaviour control.

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Objective. To investigate the mechanism underlying neutrophil migration into the articular cavity in experimental arthritis and, by extension, human-inflammatory synovitis. Methods. Antigen-induced arthritis (AIA) was generated in mice with methylated bovine serum albumin (mBSA). Migration assays and histologic analysis were used to evaluate neutrophil recruitment to knee joints. Levels of inflammatory mediators were measured by enzyme-linked immunosorbent assay. Antibodies and pharmacologic inhibitors were used in vivo to determine the role of specific disease mediators. Samples of synovial tissue and synovial fluid from rheumatoid arthritis (RA) or osteoarthritis patients were evaluated for CXCL1 and CXCL5 expression. Results. High levels of CXCL1, CXCL5, and leukotriene B-4 (LTB4) were expressed in the joints of arthritic mice. Confirming their respective functional roles, repertaxin (a CXCR1/CXCR2 receptor antagonist), anti-CXCL1 antibody, anti-CXCL5 antibody, and MK886 (a leukotriene synthesis inhibitor) reduced mBSA-induced neutrophil migration to knee joints. Repertaxin reduced LTB4 production in joint tissue, and neutrophil recruitment induced by CXCL1 or CXCL5 was inhibited by MK886, suggesting a sequential mechanism. Levels of both CXCL1 and CXCL5 were elevated in synovial fluid and were released in vitro by RA synovial tissues. Moreover, RA synovial fluid neutrophils stimulated with CXCL1 or CXCL5 released significant amounts of LTB4. Conclusion. Our data implicate CXCL1, CXCL5, and LTB4, acting sequentially, in neutrophil migration in AIA. Elevated levels of CXCL1 and CXCL5 in the synovial compartment of RA patients provide robust comparative data indicating that this mechanism plays a role in inflammatory joint disease. Together, these results suggest that inhibition of. CXCL1, CXCL5, or LTB4 may represent a potential therapeutic strategy in RA.

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Infection with any 1 of 4 dengue viruses produces a spectrum of clinical illness ranging from a mild undifferentiated febrile illness to dengue fever (DF) to dengue hemorrhagic fever (DHF), a potentially life-threatening disease. The morbidity and mortality of DHF can be reduced by early hospitalization and careful supportive care. To determine its usefulness as a predictor of DHF, plasma levels of the secreted dengue virus nonstructural protein NS1 (sNS1) were measured daily in 32 children with dengue-2 virus infections participating in a prospective, hospital-based study. Free sNS1 levels in plasma correlated with viremia levels and were higher in patients with DHF than in those with DF. An elevated free sNS1 level (greater than or equal to600 ng/mL) within 72 h of illness onset identified patients at risk for developing DHF.

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This article describes work performed on the assessment of the levels of airborne ultrafine particles emitted in two welding processes metal-active gas (MAG) of carbon steel and friction-stir welding (FSW) of aluminium in terms of deposited area in alveolar tract of the lung using a nanoparticle surface area monitor analyser. The obtained results showed the dependence from process parameters on emitted ultrafine particles and clearly demonstrated the presence of ultrafine particles, when compared with background levels. The obtained results showed that the process that results on the lower levels of alveolar-deposited surface area is FSW, unlike MAG. Nevertheless, all the tested processes resulted in important doses of ultrafine particles that are to be deposited in the human lung of exposed workers.

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This article describes work performed on the assessment of the levels of airborne ultrafine particles emitted in two welding processes metal-active gas (MAG) of carbon steel and friction-stir welding (FSW) of aluminium in terms of deposited area in alveolar tract of the lung using a nanoparticle surface area monitor analyser. The obtained results showed the dependence from process parameters on emitted ultrafine particles and clearly demonstrated the presence of ultrafine particles, when compared with background levels. The obtained results showed that the process that results on the lower levels of alveolar-deposited surface area is FSW, unlike MAG. Nevertheless, all the tested processes resulted in important doses of ultrafine particles that are to be deposited in the human lung of exposed workers.

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In the stair nested designs with u factors we have u steps and a(1), ... , a(u) "active" levels. We would have a(1) observations with different levels for the first factor each of them nesting a single level of each of the remaining factors; next a(2) observations with level a(1) + 1 for the first factor and distinct levels for the second factor each nesting a fixed level of each of the remaining factors, and so on. So the number of level combinations is Sigma(u)(i=1) a(i). In meta-analysis joint treatment of different experiments is considered. Joining the corresponding models may be useful to carry out that analysis. In this work we want joining L models with stair nesting.

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The concept of Learning Object (LO) is crucial for the standardization on eLearning. The latest LO standard from IMS Global Learning Consortium is the IMS Common Cartridge (IMS CC) that organizes and distributes digital learning content. By analyzing this new specification we considered two interoperability levels: content and communication. A common content format is the backbone of interoperability and is the basis for content exchange among eLearning systems. Communication is more than just exchanging content; it includes also accessing to specialized systems and services and reporting on content usage. This is particularly important when LOs are used for evaluation. In this paper we analyze the Common Cartridge profile based on the two interoperability levels we proposed. We detail its data model that comprises a set of derived schemata referenced on the CC schema and we explore the use of the IMS Learning Tools Interoperability (LTI) to allow remote tools and content to be integrated into a Learning Management System (LMS). In order to test the applicability of IMS CC for automatic evaluation we define a representation of programming exercises using this standard. This representation is intended to be the cornerstone of a network of eLearning systems where students can solve computer programming exercises and obtain feedback automatically. The CC learning object is automatically generated based on a XML dialect called PExIL that aims to consolidate all the data need to describe resources within the programming exercise life-cycle. Finally, we test the generated cartridge on the IMS CC online validator to verify its conformance with the IMS CC specification.

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The integration of wind power in eletricity generation brings new challenges to unit commitment due to the random nature of wind speed. For this particular optimisation problem, wind uncertainty has been handled in practice by means of conservative stochastic scenario-based optimisation models, or through additional operating reserve settings. However, generation companies may have different attitudes towards operating costs, load curtailment, or waste of wind energy, when considering the risk caused by wind power variability. Therefore, alternative and possibly more adequate approaches should be explored. This work is divided in two main parts. Firstly we survey the main formulations presented in the literature for the integration of wind power in the unit commitment problem (UCP) and present an alternative model for the wind-thermal unit commitment. We make use of the utility theory concepts to develop a multi-criteria stochastic model. The objectives considered are the minimisation of costs, load curtailment and waste of wind energy. Those are represented by individual utility functions and aggregated in a single additive utility function. This last function is adequately linearised leading to a mixed-integer linear program (MILP) model that can be tackled by general-purpose solvers in order to find the most preferred solution. In the second part we discuss the integration of pumped-storage hydro (PSH) units in the UCP with large wind penetration. Those units can provide extra flexibility by using wind energy to pump and store water in the form of potential energy that can be generated after during peak load periods. PSH units are added to the first model, yielding a MILP model with wind-hydro-thermal coordination. Results showed that the proposed methodology is able to reflect the risk profiles of decision makers for both models. By including PSH units, the results are significantly improved.

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Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of s√=8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT>120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between EmissT>150 GeV and EmissT>700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with large extra spatial dimensions, pair production of weakly interacting dark matter candidates, and production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presented.

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OBJECTIVE: Population-based studies on excessive daytime sleepiness (EDS) in older adults living in less developed countries are scarce. The purpose of this paper was to estimate the prevalence of EDS and its association with sociodemographic characteristics and lifestyle factors in Brazilian community-dwelling older adults. METHODS: The study was carried out in Bambuí, a city in the state of Minas Gerais, Brazil. EDS was defined as the presence of sleepiness in the last month occurring three or more times per week, with any interference in usual activities. The exploratory variables were: gender, age, skin color, marital status, schooling level, current employment status, religion, recent migration, smoking, binge drinking and physical activities during leisure time. RESULTS: Of 1,742 residents aged > 60 years, 1,514 (86.9%) participated. The prevalence of EDS was 13%. After adjustment for confounders, female gender and low schooling level remained positively and independently associated with EDS. CONCLUSIONS: The prevalence of EDS in the study population was within the range observed in studies carried out in developed countries. The most impressive finding was the association of EDS with schooling, indicating that even in a population with low levels of schooling, this was an important factor to explain the distribution of EDS.