930 resultados para High ball games with striking implement. Racket games
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In this paper, mixed spectral-structural kernel machines are proposed for the classification of very-high resolution images. The simultaneous use of multispectral and structural features (computed using morphological filters) allows a significant increase in classification accuracy of remote sensing images. Subsequently, weighted summation kernel support vector machines are proposed and applied in order to take into account the multiscale nature of the scene considered. Such classifiers use the Mercer property of kernel matrices to compute a new kernel matrix accounting simultaneously for two scale parameters. Tests on a Zurich QuickBird image show the relevance of the proposed method : using the mixed spectral-structural features, the classification accuracy increases of about 5%, achieving a Kappa index of 0.97. The multikernel approach proposed provide an overall accuracy of 98.90% with related Kappa index of 0.985.
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BACKGROUND: There is considerable interindividual variability in pulmonary artery pressure among high-altitude (HA) dwellers, but the underlying mechanism is not known. At low altitude, a patent foramen ovale (PFO) is present in about 25% of the general population. Its prevalence is increased in clinical conditions associated with pulmonary hypertension and arterial hypoxemia, and it is thought to aggravate these problems. METHODS: We searched for a PFO (transesophageal echocardiography) in healthy HA dwellers (n = 22) and patients with chronic mountain sickness (n = 35) at 3,600 m above sea level and studied its effects (transthoracic echocardiography) on right ventricular (RV) function, pulmonary artery pressure, and vascular resistance at rest and during mild exercise (50 W), an intervention designed to further increase pulmonary artery pressure. RESULTS: The prevalence of PFO (32%) was similar to that reported in low-altitude populations and was not different in participants with and without chronic mountain sickness. Its presence was associated with RV enlargement at rest and an exaggerated increase in right-ventricular-to-right-atrial pressure gradient (25 ± 7 mm Hg vs 15 ± 9 mm Hg, P < .001) and a blunted increase in fractional area change of the right ventricle (3% [-1%, 5%] vs 7% [3%, 16%], P = .008) during mild exercise. CONCLUSIONS: These findings show, we believe for the first time, that although the prevalence of PFO is not increased in HA dwellers, its presence appears to facilitate pulmonary vasoconstriction and RV dysfunction during a mild physical effort frequently associated with daily activity. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01182792; URL: www.clinicaltrials.gov.
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Postprandial inflammation is an important factor for human health since chronic low-grade inflammation is associated with chronic diseases. Dairy products have a weak but significant anti-inflammatory effect on postprandial inflammation. The objective of the present study was to compare the effect of a high-fat dairy meal (HFD meal), a high-fat non-dairy meal supplemented with milk (HFM meal) and a high-fat non-dairy control meal (HFC meal) on postprandial inflammatory and metabolic responses in healthy men. A cross-over study was conducted in nineteen male subjects. Blood samples were collected before and 1, 2, 4 and 6 h after consumption of the test meals. Plasma concentrations of insulin, glucose, total cholesterol, LDL-cholesterol, HDL-cholesterol, TAG and C-reactive protein (CRP) were measured at each time point. IL-6, TNF-α and endotoxin concentrations were assessed at baseline and endpoint (6 h). Time-dependent curves of these metabolic parameters were plotted, and the net incremental AUC were found to be significantly higher for TAG and lower for CRP after consumption of the HFM meal compared with the HFD meal; however, the HFM and HFD meals were not different from the HFC meal. Alterations in IL-6, TNF-α and endotoxin concentrations were not significantly different between the test meals. The results suggest that full-fat milk and dairy products (cheese and butter) have no significant impact on the inflammatory response to a high-fat meal.
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PURPOSE: This multicenter phase III study evaluated the efficacy and safety of lapatinib, an epidermal growth factor receptor/ErbB2 inhibitor, administered concomitantly with chemoradiotherapy and as maintenance monotherapy in patients with high-risk surgically treated squamous cell carcinoma of the head and neck (SCCHN). PATIENTS AND METHODS: Patients with resected stage II to IVA SCCHN, with a surgical margin ≤ 5 mm and/or extracapsular extension, were randomly assigned to chemoradiotherapy (66 Gy total radiation dose and cisplatin 100 mg/m(2) per day administered on days 1, 22, and 43) plus placebo or lapatinib (1,500 mg per day) before and during chemoradiotherapy, followed by 12 months of maintenance monotherapy. RESULTS: Six hundred eighty-eight patients were enrolled (lapatinib, n = 346; placebo, n = 342). With a median follow-up time of 35.3 months, the study ended early because of the apparent plateauing of disease-free survival (DFS) events. Median DFS assessed by an independent review committee was 53.6 months and not reached for lapatinib and placebo, respectively (hazard ratio, 1.10; 95% CI, 0.85 to 1.43). Investigator-assessed results confirmed the independent review committee assessment. No significant differences in DFS by human papillomavirus status or overall survival were observed between treatment arms. Similar numbers of patients in both treatment arms experienced adverse events (AEs), with more patients in the lapatinib arm than the placebo arm experiencing serious AEs (48% v 40%, respectively). The most commonly observed treatment-related AEs were diarrhea and rash, both predominantly in the lapatinib arm. CONCLUSION: Addition of lapatinib to chemoradiotherapy and its use as long-term maintenance therapy does not offer any efficacy benefits and had additional toxicity compared with placebo in patients with surgically treated high-risk SCCHN.
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Power transformer is the most expensive equipment on a substation. It is always necessary to get needed benefit with the lowest expenses. Producing of power transformers with reduced insulation strength is one of the possible ways to reduce expenses. Exploitation of such transformers was begun in the end of 70-th in the last century. Protection from overvoltages was done with valve-type magnetic combined surge arresters with increased blanking voltage during switching overvoltages. Nowadays there is the necessity of replacement of those devices. That’s why modernized nonlinear surge arrester was invented. This master’s thesis is focused on the use research of that modernized device in comparison with usual nonlinear surge arresters. The goal is to show the lightning overvoltages level using different types of nonlinear surge arresters and then calculations of the lightning protection reliability.
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Cardioplegic reperfusion during a long term ischemic period interrupts cardiac surgery and also increases cellular edema due to repeated solution administration. We reviewed the clinical experiences on myocardial protection of a single perfusion with histidine-tryptophan-ketoglutarate (HTK) for high-risk patients with severe pulmonary arterial hypertension associated with complex congenital heart disease. This retrospective study included 101 high-risk patients undergoing arterial switch operation between March 2001 and July 2012. We divided the cohort into two groups: HTK group, myocardial protection was carried out with one single perfusion with HTK solution; and St group, myocardial protection with conventional St. Thomas' crystalloid cardioplegic solution. The duration of cardiopulmonary bypass did not differ between the two groups. The mortality, morbidity, ICU stay, post-operative hospitalization time, and number of transfusions in HTK group were lower than those in St group (P<0.05). Univariate and multivariate analysis showed that HTK is a statistically significant independent predictor of decreased early mortality and morbidity (P<0.05). In conclusion, HTK solution seems to be an effective and safe alternative to St. Thomas' solution for cardioplegic reperfusion in high-risk patients with complex congenital heart disease.
Inference for nonparametric high-frequency estimators with an application to time variation in betas
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We consider the problem of conducting inference on nonparametric high-frequency estimators without knowing their asymptotic variances. We prove that a multivariate subsampling method achieves this goal under general conditions that were not previously available in the literature. We suggest a procedure for a data-driven choice of the bandwidth parameters. Our simulation study indicates that the subsampling method is much more robust than the plug-in method based on the asymptotic expression for the variance. Importantly, the subsampling method reliably estimates the variability of the Two Scale estimator even when its parameters are chosen to minimize the finite sample Mean Squared Error; in contrast, the plugin estimator substantially underestimates the sampling uncertainty. By construction, the subsampling method delivers estimates of the variance-covariance matrices that are always positive semi-definite. We use the subsampling method to study the dynamics of financial betas of six stocks on the NYSE. We document significant variation in betas within year 2006, and find that tick data captures more variation in betas than the data sampled at moderate frequencies such as every five or twenty minutes. To capture this variation we estimate a simple dynamic model for betas. The variance estimation is also important for the correction of the errors-in-variables bias in such models. We find that the bias corrections are substantial, and that betas are more persistent than the naive estimators would lead one to believe.
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The thesis deals with the study of super conducting properties of layered cuprates within the frame work of a modified Lawrence-Doniach (LD) model. The thesis is organized in seven chapters. Chapter I is a survey of the phenomena and theories of conventional superconductivity which can serve as a springboard for launching the study of the new class of oxide superconductors and it also includes a chronological description of the efforts made to overcome the temperature barrier. Chapter II deals with the structure and properties of the copper oxide superconductors and also the experimental constraints on the theories of high te:::nperature superconductivity. A modified Lawrence-Doniach type of phenomenological model which forms the basis of the presnt study is also discussed. In chapter III~ the temperature dependence of the upper critical field both parallel and perpendicular to the layers is determined and the results are compared with d.c. magnetization measurements on different superconducting compoilllds. The temperature and angular dependence of the lower critical field both parallel and perpendicular to the layers is also discussed. Chapters IV, V and VI deal with thermal fluctuation effects on superconducting properties. Fluctuation specific heat is studied in chapter IV. Paraconductivity both parallel and perpendicular to the layers is discussed in chapter V. Fluctuation diamagnetism is dealt with in chapter VI. Dimensional cross over in the fluctuation regime of all these quantities is also discussed. Chapter VII gives a summary of the results and the conclusions arrived at.
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We investigate the potential of a future kilometer-scale neutrino telescope, such as the proposed IceCube detector in the South Pole, to measure and disentangle the yet unknown components of the cosmic neutrino flux, the prompt atmospheric neutrinos coming from the decay of charmed particles and the extra-galactic neutrinos in the 10 TeV to 1 EeV energy range. Assuming a power law type spectra, dphi(nu)/dE(nu)similar toalphaE(nu)(beta), we quantify the discriminating power of the IceCube detector and discuss how well we can determine magnitude (alpha) as well as slope (beta) of these two components of the high energy neutrino spectrum, taking into account the background coming from the conventional atmospheric neutrinos.
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Some dynamical properties of a bouncing ball model under the presence of an external force modelled by two nonlinear terms are studied. The description of the model is made by the use of a two-dimensional nonlinear measure-preserving map on the variable's velocity of the particle and time. We show that raising the straight of a control parameter which controls one of the nonlinearities, the positive Lyapunov exponent decreases in the average and suffers abrupt changes. We also show that for a specific range of control parameters, the model exhibits the phenomenon of Fermi acceleration. The explanation of both behaviours is given in terms of the shape of the external force and due to a discontinuity of the moving wall's velocity.
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We examine a Lipkin based two-level pairing model at finite temperature and in the thermodynamic limit. Whereas at T = 0 the model exhibits a superconducting ground state for sufficiently high values of the coupling constant, a partially superconducting phase in which some of the particles are paired, is found to survive at high temperatures in a special treatment. This phase is a mixture of abnormally-occupied eigenstates, which lie at higher energy, of the interactionless model Hamiltonian.