998 resultados para Loop Region
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The objective of this work was to evaluate the efficiency of soybean (Glycine max) in intercepting and using solar radiation under natural field conditions, in the Amazon region, Brazil. The meteorological data and the values of soybean growth and leaf area were obtained from an agrometeorological experiment carried out in Paragominas, Pará state, during 2007 and 2008. The radiation use efficiency (RUE) was obtained from the ratio between the above-ground biomass production and the intercepted photosynthetically active radiation (PAR) accumulated to 99 and 95 days after sowing, in 2007 and 2008, respectively. Climatic conditions during the experiment were very distinct, with reduction in rainfall in 2007, which began during the soybean mid-cycle, due to the El Niño phenomenon. An important reduction in the leaf area index and biomass production was observed during 2007. Under natural field conditions in the Amazon region, the values of RUE were 1.46 and 1.99 g MJ-1 PAR in the 2007 and 2008 experiments, respectively. The probable reason for the differences found between these years might be associated to the water restriction in 2007 coupled with the higher air temperature and vapor pressure deficit, and also to the increase in the fraction of diffuse radiation that reached the land surface in 2008.
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The objective of this work was to evaluate the reliability of eddy covariance measurements, analyzing the energy balance components, evapotranspiration and energy balance closure in dry and wet growing seasons, in a banana orchard. The experiment was carried out at a farm located within the irrigation district of Quixeré, in the Lower Jaguaribe basin, in Ceará state, Brazil. An eddy covariance system was used to measure the turbulent flux. An automatic weather station was installed in a grass field to obtain the reference evapotranspiration (ET0) from the combined FAO-Penman-Monteith method. Wind speed and vapor pressure deficit are the most important variables on the evaporative process in both growing seasons. In the dry season, the heat fluxes have a similar order of magnitude, and during the wet season the latent heat flux is the largest. The eddy covariance system had acceptable reliability in measuring heat flux, with actual evapotranspiration results comparing well with those obtained by using the water balance method. The energy balance closure had good results for the study area, with mean values of 0.93 and 0.86 for the dry and wet growing seasons respectively.
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We consider the numerical treatment of the optical flow problem by evaluating the performance of the trust region method versus the line search method. To the best of our knowledge, the trust region method is studied here for the first time for variational optical flow computation. Four different optical flow models are used to test the performance of the proposed algorithm combining linear and nonlinear data terms with quadratic and TV regularization. We show that trust region often performs better than line search; especially in the presence of non-linearity and non-convexity in the model.
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The omega-loop gastric bypass (OLGBP), also called "mini-gastric bypass" or "single-anastomosis" gastric bypass is a form of gastric bypass where a long, narrow gastric pouch is created and anastomosed to the jejunum about 200- 250 cm from the angle of Treitz in an omega loop fashion, thereby avoiding a jejuno-jejunostomy.Proponents of the OLGBP claim that it is a safer and simpler operation than the traditional Roux-en-Y gastric bypass (RYGBP), easier to teach, that gives the same results in terms of weight loss than the RYGBP. One randomized study comparing the two techniques showed similar results after five years.The OLGBP is criticized because it creates an anastomosis between the gastric pouch and the jejunum where a large amount of biliopancreatic juices travel, thereby creating a situation where reflux of the latter into the stomach and distal esophagus is likely to develop. Such a situation has clearly been associated, in several animal studies, with an increased incidence of gastric cancer, especially at or close to the gastro-jejunostomy, and with an increased risk of lower esophageal cancer. In clinical practice, omega-loop gastrojejunostomies such as those used for reconstruction after gastric resection for benign disease or distal gastric cancer have been associated with the so called classical anastomotic cancer, linked to biliary reflux into the stomach, despite the fact that epidemiological studies about this do not show uniform results. Although no evidence at the present time links OLGBP to an increased risk of gastric cancer in the human, this possibility raises a concern among many bariatric surgeons, especially in the view that bariatric surgery is performed in relatively young patients with a long life expectancy, hence prone to develop cancer if indeed the risk is increased. Another arguments used against the OLGBP is that the jejuno-jejunostomy in the traditional RYGBP is easy to perform and associated with virtually no complication.Supporters of the OLGBP claim that the liquid that refluxes into the stomach after their procedure is not pure bile and pancreatic juice, but a combination of those with jejunal secretions, and that the latter is not as harmful. We would urge the proponents of the OLGBP to undertake the necessary animal studies to show that their assumption is indeed true before the procedure is performed widely, possibly leading to the development of hundreds of late gastric or esophageal carcinoma in the bariatric population. In the meantime, we strongly believe that RYGBP should remain the gold standard in gastric bypass surgery for morbid obesity.
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Proteoglycans (PGs) are a major component of the extracellular matrix in many tissues and function as structural and regulatory molecules. PGs are composed of core proteins and glycosaminoglycan (GAG) side chains. The biosynthesis of GAGs starts with the linker region that consists of four sugar residues and is followed by repeating disaccharide units. By exome sequencing, we found that B3GALT6 encoding an enzyme involved in the biosynthesis of the GAG linker region is responsible for a severe skeletal dysplasia, spondyloepimetaphyseal dysplasia with joint laxity type 1 (SEMD-JL1). B3GALT6 loss-of-function mutations were found in individuals with SEMD-JL1 from seven families. In a subsequent candidate gene study based on the phenotypic similarity, we found that B3GALT6 is also responsible for a connective tissue disease, Ehlers-Danlos syndrome (progeroid form). Recessive loss-of-function mutations in B3GALT6 result in a spectrum of disorders affecting a broad range of skeletal and connective tissues characterized by lax skin, muscle hypotonia, joint dislocation, and spinal deformity. The pleiotropic phenotypes of the disorders indicate that B3GALT6 plays a critical role in a wide range of biological processes in various tissues, including skin, bone, cartilage, tendon, and ligament.
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The objective of this work was to evaluate the effects of lignin, hemicellulose, and cellulose concentrations in the decomposition process of cover plant residues with potential use in no-tillage with corn, for crop-livestock integrated system, in the Cerrado region. The experiment was carried out at Embrapa Cerrados, in Planaltina, DF, Brazil in a split plot experimental design. The plots were represented by the plant species and the subplots by harvesting times, with three replicates. The cover plants Urochloa ruziziensis, Canavalia brasiliensis, Cajanus cajan, Pennisetum glaucum, Mucuna aterrima, Raphanus sativus, Sorghum bicolor were evaluated together with spontaneous plants in the fallow. Cover plants with lower lignin concentrations and, consequently, higher residue decomposition such as C. brasiliensis and U. ruziziensis promoted higher corn yield. High concentrations of lignin inhibit plant residue decomposition and this is favorable for the soil cover. Lower concentrations of lignin result in accelerated plant decomposition, more efficient nutrient cycling, and higher corn yield.
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OBJECTIVE: To determine whether infusion line compliance contributes to irregular drug delivery during vertical displacement of syringe pumps. DESIGN: Five different commercially available infusion lines were studied at infusion rates of 0.5, 1.0, and 1.5 ml/h. Zero drug delivery time was measured after acute line loop formation (70 cm) using an electronic balance. Compliance of each infusion line was calculated using a pressure transducer and measurement of the occlusion release bolus at 300 mmHg occlusion pressure. Finally, the influence of infusion line compliance on drug delivery during acute lowering of the syringe pump was studied using low- and high-compliance infusion lines. RESULTS: Acute line loop formation resulted in zero drug delivery time from 5.1 +/- 1.5 to 44.0 +/- 6.8 s at flow rates of 0.5 ml/h. Increased flow rates significantly reduced loop-induced flow variability. A close correlation was found between zero drug delivery time and calculated infusion line compliance at 0.5 ml/h (linear regression R2 = 0.79). Lowering of the syringe pump 50 cm prolonged zero drug delivery time from 295.8 +/- 20.7 s with the low-compliance tube to 463.3 +/- 24.0 s with the high-compliance infusion line. CONCLUSIONS: Infusion line compliance contributes to irregular drug delivery associated with vertical displacement of syringe pumps. Siphoning of the infusion line during patient care should be avoided, and flow rates of 1 ml/h or higher are recommended. Low-compliance infusion lines are indicated whenever highly short-acting vasoactive drugs at low delivery rates are administered.
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A power point made by the IDPH on promoting and protecting the health of Iowans in the workplace.
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The effect of motor training using closed loop controlled Functional Electrical Stimulation (FES) on motor performance was studied in 5 spinal cord injured (SCI) volunteers. The subjects trained 2 to 3 times a week during 2 months on a newly developed rehabilitation robot (MotionMaker?). The FES induced muscle force could be adequately adjusted throughout the programmed exercises by the way of a closed loop control of the stimulation currents. The software of the MotionMaker? allowed spasms to be detected accurately and managed in a way to prevent any harm to the SCI persons. Subjects with incomplete SCI reported an increased proprioceptive awareness for motion and were able to achieve a better voluntary activation of their leg muscles during controlled FES. At the end of the training, the voluntary force of the 4 incomplete SCI patients was found increased by 388% on their most affected leg and by 193% on the other leg. Active mobilisation with controlled FES seems to be effective in improving motor function in SCI persons by increasing the sensory input to neuronal circuits involved in motor control as well as by increasing muscle strength.
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The implantable loop recorder developed by Medtronic (Reveal plus) is a small device inserted subcutaneously under local anesthesia in patients with syncope of unexplained origin. This device enables a single lead-ECG recording and has autonomy of two years. Memories are activated during episodes of bradycardia or tachycardia, either automatically or manually. Several studies have shown a high diagnostic rate reaching 50% and demonstrated its cost-effectiveness. There is also a significant reduction in syncopal episodes and a higher quality of life score in patients with syncope of unexplained origin.
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Peer reviewed
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OBJECTIVE: To investigate the determinants and the 4-year evolution of the forgoing of healthcare for economic reasons in Switzerland. METHOD: Population-based survey (2007-2010) of a representative sample aged 35-74years in the Canton of Geneva, Switzerland. Healthcare forgone, socioeconomic and insurance status, marital status, and presence of dependent children were assessed using standardized methods. RESULTS: A total of 2601 subjects were included in the analyses. Of the subjects, 13.8% (358/2601) reported having forgone healthcare for economic reasons, with the percentage varying from 3.7% in the group with a monthly income ≥13,000CHF (1CHF≈1$) to 30.9% in the group with a monthly income <3000CHF. In subjects with a monthly income <3000CHF, the percentage who had forgone healthcare increased from 22.5% in 2007/8 to 34.7% in 2010 (P trend=0.2). Forgoing healthcare for economic reasons was associated with lower income, female gender, smoking status, lower job position, having dependent children, being divorced and single, paying a higher deductible, and receiving a premium subsidy. CONCLUSION: In a Swiss region with universal health insurance coverage, the reported prevalence of forgoing healthcare for economic reasons was high and greatly dependent on socioeconomic factors. Our data suggested an increasing trend among participants with the lowest income.