988 resultados para Dimensional reduction
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Evidence indicates that exposure to high levels of noise adversely affects human health, and these effects are dependent upon various factors. In hospitals, there are many sources of noise, and high levels exert an impact on patients and staff, increasing both recovery time and stress, respectively. The goal of this pilot study was to develop, implement and evaluate the effectiveness of a training program (TP) on noise reduction in a Neonatal Intensive Care Units (NICU) by comparing the noise levels before and after the implementation of the program. A total of 79 health professionals participated in the study. The measurements of sound pressure levels took into account the layout of the unit and location of the main sources of noise. General results indicated that LAeq levels before implementation of the training program were often excessive, ranging from 48.7 ± 2.94 dBA to 71.7 ± 4.74 dBA, exceeding international guidelines. Similarly following implementation of the training program noise levels remained unchanged (54.5 ± 0.49 dBA to 63.9 ± 4.37 dBA), despite a decrease in some locations. There was no significant difference before and after the implementation of TP. However a significant difference was found for Lp, Cpeak, before and after training staff, suggesting greater care by healthcare professionals performing their tasks. Even recognizing that a TP is quite important to change behaviors, this needs to be considered in a broader context to effectively control noise in the NICU.
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Dissertation submitted to obtain the phD degree in Biochemistry, specialty in Physical- Biochemistry, by the Faculdade de Ciências e Tecnologia from the Universidade Nova de Lisboa
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Selenium modified ruthenium electrocatalysts supported on carbon black were synthesized using NaBH4 reduction of the metal precursor. Prepared Ru/C electrocatalysts showed high dispersion and very small averaged particle size. These Ru/C electrocatalysts were subsequently modified with Se following two procedures: (a) preformed Ru/carbon catalyst was mixed with SeO2 in xylene and reduced in H2 and (b) Ru metal precursor was mixed with SeO2 followed by reduction with NaBH4. The XRD patterns indicate that a pyrite-type structure was obtained at higher annealing temperatures, regardless of the Ru:Se molar ratio used in the preparation step. A pyrite-type structure also emerged in samples that were not calcined; however, in this case, the pyrite-type structure was only prominent for samples with higher Ru:Se ratios. The characterization of the RuSe/C electrocatalysts suggested that the Se in noncalcined samples was present mainly as an amorphous skin. Preliminary study of activity toward oxygen reduction reaction (ORR) using electrocatalysts with a Ru:Se ratio of 1:0.7 indicated that annealing after modification with Se had a detrimental effect on their activity. This result could be related to the increased particle size of crystalline RuSe2 in heat-treated samples. Higher activity of not annealed RuSe/C catalysts could also be a result of the structure containing amorphous Se skin on the Ru crystal. The electrode obtained using not calcined RuSe showed a very promising performance with a slightly lower activity and higher overpotential in comparison with a commercial Pt/C electrode. Single wall carbon nanohorns (SWNH) were considered for application as ORR electrocatalysts' supports. The characterization of SWNH was carried out regarding their tolerance toward strong catalyzed corrosion conditions. Tests indicated that SWNH have a three times higher electrochemical surface area (ESA) loss than carbon black or Pt commercial electrodes.
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The shifted Legendre orthogonal polynomials are used for the numerical solution of a new formulation for the multi-dimensional fractional optimal control problem (M-DFOCP) with a quadratic performance index. The fractional derivatives are described in the Caputo sense. The Lagrange multiplier method for the constrained extremum and the operational matrix of fractional integrals are used together with the help of the properties of the shifted Legendre orthonormal polynomials. The method reduces the M-DFOCP to a simpler problem that consists of solving a system of algebraic equations. For confirming the efficiency and accuracy of the proposed scheme, some test problems are implemented with their approximate solutions.
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OBJECTIVES: To assess the feasibility of performing pulmonary angiography using MRI with contrast enhancement in patients with pulmonary vascular disease. METHODS: We present our experience in ten individuals, two controls and eight patients who underwent the exam after injection of a gadolinium-based contrast agent on a 1 Tesla MR scanner using a time-of-flight sequence and breath-holding during injection of contrast. RESULTS: Pathology in the main pulmonary artery and its major branches was detected easily while resolution at the segmental and subsegmental levels was inadequate. CONCLUSION: Contrast-enhanced magnetic resonance pulmonary angiography is feasible on a 1 Tesla MR scanner for the study of pathology of the main pulmonary artery and its major branches, like massive pulmonary embolism. However its ability to detect and define distal vessel pathology as found in chronic thromboembolic pulmonary hypertension and small pulmonary emboli is limited.
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Robotica 2012: 12th International Conference on Autonomous Robot Systems and Competitions April 11, 2012, Guimarães, Portugal
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INTRODUCTION: Recent clinical trials have studied parameters that could predict response to cardiac resynchronization therapy (CRT) in patients with advanced heart failure. Left ventricular end-diastolic dimension (LVEDD) is regarded as a possible predictor of response to CRT. OBJECTIVE: To study the response to CRT in patients with very dilated cardiomyopathy, i.e. those at a more advanced stage of the pathology, analyzing both the responder rate and reverse remodeling in two groups of patients classified according to LVEDD. METHODS: We performed a retrospective analysis of 71 patients who underwent CRT (aged 62 +/- 11 years; 65% male; 93% in NYHA functional class > or = III; 31% with ischemic cardiomyopathy; left ventricular ejection fraction [LVEF] 25.6 +/- 6.8%; 32% in atrial fibrillation; QRS 176 +/- 31 ms). Twenty-two (31%) patients with LVEDD > or = 45 mm/m2 (49.2 +/- 3.5 mm/m2) were considered to have very dilated cardiomyopathy (Group A) and 49 patients had LVEDD > 37 mm/m2 and < 45 mm/m2 (39.4 +/- 3.8 mm/m2) (Group B). All patients were assessed by two-dimensional echocardiography at baseline and six months after CRT. The following parameters were analyzed: NYHA functional class, LVEF and LVEDD. Responders were defined clinically (improvement of > or = 1 NYHA class) and by echocardiography, with a minimum 15% increase over baseline LVEF combined with a reduction in LVEDD (reverse remodeling). RESULTS: There were no significant differences in baseline demographic characteristics between the two groups. At six-month followup, we observed an improvement in LVEF (delta 8.5 +/- 11.8%) and a reduction in LVEDD (delta 3.7 +/- 6.8 mm/m2), with fifty-seven (79%) patients being classified as clinical responders. The percentage of patients with reverse remodeling was similar in both groups (64% vs. 73%, p = NS), as were percentages of improved LVEF (delta 6.3 +/- 11% vs. delta 9.6 +/- 12%; p = NS) and decreased LVEDD (delta 3.7 +/- 5.5 mm/m2 vs. delta 3.7 +/- 7.4 mm/m2; p = NS). We found a higher percentage of clinical responders in patients with very dilated cardiomyopathy (96% vs. 72%, p < 0.05). CONCLUSION: In this study, a significant number of responders showed reverse remodeling after CRT. Although a higher percentage of patients with very dilated cardiomyopathy showed improvement in functional class, the extent of reverse remodeling was similar in both groups.
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Helicobacter pylori is a bacterium recognized as the major cause of peptic ulcer and chronic gastritis. Recently, a proteome-based approach was developed to investigate pathogenic factors related to H. pylori. In this preliminary study, H. pylori strains were isolated from gastric biopsies of patients with chronic gastritis and duodenal ulcers. A partial proteomic analysis of H. pylori strains was performed by bacterial lyses and proteins were separated by two-dimensional gel electrophoresis (2-DE). A comparative analysis was performed to verify a differential protein expression between these two 2-DE maps. These data should be useful to clarify the role of different proteins related to bacterial pathogenesis. This study will be completed using a larger number of samples and protein identification of H. pylori by MALDI-TOF mass spectrometry.
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Decreased responses to hepatitis B vaccine have been associated with some host conditions including obesity. Susceptible non-responders to a primary three-dose vaccine series should be revaccinated. Those who maintain a non-responder condition after revaccination with three vaccine doses are unlikely to develop protection using more doses. This is a description of an obese woman who received six doses of hepatitis B vaccine and persisted as a non-responder. She was submitted to a vertical banded gastroplasty Roux-en-Y gastric bypass Capellas's technique. After weight reduction, she received three additional doses of vaccine and seroconverted. Further studies should help clarify the need to evaluate antibody levels and eventually revaccinate the increasing population of individuals who undergo weight reduction.
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BACKGROUND AND PURPOSE: A single bout of aerobic exercise acutely decreases blood pressure, even in older adults with hypertension. Nonetheless, blood pressure responses to aerobic exercise in very old adults with hypertension have not yet been documented. Therefore, this study aimed to assess the effect of a single session of aerobic exercise on postexercise blood pressure in very old adults with hypertension. METHODS: Eighteen older adults with essential hypertension were randomized into exercise (N = 9, age: 83.4 ± 3.2 years old) or control (N = 9, age: 82.7 ± 2.5 years old) groups. The exercise group performed a session of aerobic exercise constituting 2 periods of 10 minutes of walking at an intensity of 40% to 60% of the heart rate reserve. The control group rested for the same period of time. Anthropometric variables and medication status were evaluated at baseline. Heart rate and systolic and diastolic blood pressures were measured at baseline, after exercise, and at 20 and 40 minutes postexercise. RESULTS: Systolic blood pressure showed a significant interaction for group × time (F3,24 = 6.698; P = .002; ηp = 0.153). In the exercise group, the systolic blood pressure at 20 (127.3 ± 20.9 mm Hg) and 40 minutes (123.7 ± 21.0 mm Hg) postexercise was significantly lower in comparison with baseline (135.6 ± 20.6 mm Hg). Diastolic blood pressure did not change. Heart rate was significantly higher after the exercise session. In the control group, no significant differences were observed. CONCLUSIONS: A single session of aerobic exercise acutely reduces blood pressure in very old adults with hypertension and may be considered an important nonpharmacological strategy to control hypertension in this age group.
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The majority of infections caused by R. equi occur in hosts with some degree of cell-mediated immunodeficiency. Immunocompetent individuals are infrequently affected and usually present with localized disease. Infections of the skin or related structures are uncommon and are usually related to environmental contamination. The microbiology laboratory plays a key role in the identification of the organism since it may be mistaken for common skin flora. We describe a 31 year-old woman without medical problems who presented nine weeks after breast reduction with right breast cellulitis and purulent drainage from the surgical wound. She underwent incision and drainage, and cultures of the wound yielded Rhodococcus equi. The patient completed six weeks of antimicrobial therapy with moxifloxacin and rifampin with complete resolution.
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Dissertação para obtenção do Grau de Mestre em Engenharia Informática
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J Biol Inorg Chem (2011) 16:443–460 DOI 10.1007/s00775-010-0741-z
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J Biol Inorg Chem (2010) 15:967–976 DOI 10.1007/s00775-010-0658-6
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J. Am. Chem. Soc., 2003, 125 (51), pp 15708–15709 DOI: 10.1021/ja038344n