966 resultados para Project method


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Different compositions of Pt, PtNi, PtSn, and PtSnNi electrocatalysts supported on carbon Vulcan XC-72 were prepared through thermal decomposition of polymeric precursors. The nanoparticles were characterized by morphological and structural analyses (XRD, TEM, and EDX). XRD results revealed a face-centered cubic structure for platinum, and there was evidence that Ni and Sn atoms are incorporated into the Pt structure. The electrochemical investigation was carried out in slightly acidic medium (H(2)SO(4) 0.05 mol L(-1)), in the absence and in the presence of ethanol. Addition of Ni to Pt/C and PtSn/C catalysts significantly shifted the onset of ethanol and CO oxidations toward lower potentials, thus enhancing the catalytic activity, especially in the case of the ternary PtSnNi/C composition. Electrolysis of ethanol solutions at 0.4 V us. RHE allowed for determination of acetaldehyde and acetic acid as the reaction products, as detected by HPLC analysis. Due to the high concentration of ethanol employed in the electrolysis experiments (1.0 mol L(-1)), no formation of CO(2) was observed. Copyright (C) 2010, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

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1. Cluster analysis of reference sites with similar biota is the initial step in creating River Invertebrate Prediction and Classification System (RIVPACS) and similar river bioassessment models such as Australian River Assessment System (AUSRIVAS). This paper describes and tests an alternative prediction method, Assessment by Nearest Neighbour Analysis (ANNA), based on the same philosophy as RIVPACS and AUSRIVAS but without the grouping step that some people view as artificial. 2. The steps in creating ANNA models are: (i) weighting the predictor variables using a multivariate approach analogous to principal axis correlations, (ii) calculating the weighted Euclidian distance from a test site to the reference sites based on the environmental predictors, (iii) predicting the faunal composition based on the nearest reference sites and (iv) calculating an observed/expected (O/E) analogous to RIVPACS/AUSRIVAS. 3. The paper compares AUSRIVAS and ANNA models on 17 datasets representing a variety of habitats and seasons. First, it examines each model's regressions for Observed versus Expected number of taxa, including the r(2), intercept and slope. Second, the two models' assessments of 79 test sites in New Zealand are compared. Third, the models are compared on test and presumed reference sites along a known trace metal gradient. Fourth, ANNA models are evaluated for western Australia, a geographically distinct region of Australia. The comparisons demonstrate that ANNA and AUSRIVAS are generally equivalent in performance, although ANNA turns out to be potentially more robust for the O versus E regressions and is potentially more accurate on the trace metal gradient sites. 4. The ANNA method is recommended for use in bioassessment of rivers, at least for corroborating the results of the well established AUSRIVAS- and RIVPACS-type models, if not to replace them.

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The Australian Universities Teaching Committee (AUTC) funds projects intended to improve the quality of teaching and learning in specific disciplinary areas. The project brief for 'Learning Outcomes and Curriculum Development in Psychology' for 2004/2005 was to 'produce an evaluative overview of courses ... with a focus on the specification and assessment of learning outcomes and ... identify strategic directions for universities to enhance teaching and learning'. This project was awarded to a consortium from The University of Queensland, University of Tasmania, and Southern Cross University. The starting point for this project is an analysis of the scientist-practitioner model and its role in curriculum design, a review of current challenges at a conceptual level, and consideration of the implications of recent changes to universities relating to such things as intemationalisation of programs and technological advances. The project will seek to bring together stakeholders from around the country in order to survey the widest possible range of perspectives on the project brief requirements. It is hoped also to establish mechanisms for fiiture scholarly discussion of these issues, including the establishment of an Australian Society for the Teaching of Psychology and an annual conference.

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In this work a new approach for designing planar gradient coils is outlined for the use in an existing MRI apparatus. A technique that allows for gradient field corrections inside the diameter-sensitive volume is deliberated. These corrections are brought about by making changes to the wire paths that constitute the coil windings, and hence, is called the path correction method. The existing well-known target held method is used to gauge the performance of a typical gradient coil. The gradient coil design methodology is demonstrated for planar openable gradient coils that can be inserted into an existing MRI apparatus. The path corrected gradient coil is compared to the coil obtained using the target field method. It is shown that using a wire path correction with optimized variables, winding patterns that can deliver high magnetic gradient field strengths and large imaging regions can be obtained.

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Background Differences between women and men have been documented for both diagnostic testing and treatment in cardiology. This analysis evaluates whether low-density lipoprotein cholesterol (LDL-C) success rates according to current guidelines and high-density lipoprotein cholesterol (HDL-C) levels differ by gender in the L-TAP 2 population. Methods Patients aged >= 20 years with dyslipidemia on stable lipid-lowering therapy were assessed in 9 countries between September 2006 and April 2007. Low-density lipoprotein cholesterol goal attainment by cardiovascular risk level and region and determinants of low HDL-C were compared between genders. Results Of 9,955 patients (45.3% women) evaluated, women had a significantly lower overall LDL-C success rate than men (71.5% vs 73.7%, P = .014), due entirely to the difference in the high-risk/coronary heart disease (CHD) group (LDL-C goal <100 mg/dL, 62.6% vs 70.6%, P < .0001) Among CHD patients with >= 2 additional risk factors, only 26.7% of women and 31.5% of men (P = .021) attained the optional LDL-C goal of <70 mg/dL. High-density lipoprotein cholesterol was <50 mg/dL in 32.2% of women and <40 mg/dL in 26.8% of men (P < .0001), including 38.2% of women and 29.8% of men in the high risk/CHD group (P < .0001). Predictors of low HDL-C in women included diabetes, smoking, waist circumference, and hypertension. Conclusions Cholesterol treatment has, improved substantially since the original L-TAP a decade ago, when only 39% of women attained their LDL-C goal. However, high-risk women are undertreated compared to men, and a substantial opportunity remains to reduce their cardiovascular risk. (Am Heart J 2009; 158:860-6.)

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Background-Information about physicians` adherence to cholesterol management guidelines remains scant. The present survey updates our knowledge of lipid management worldwide. Methods and Results-Lipid levels were determined at enrollment in dyslipidemic adult patients on stable lipid-lowering therapy in 9 countries. The primary end point was the success rate, defined as the proportion of patients achieving appropriate low-density lipoprotein cholesterol (LDL-C) goals for their given risk. The mean age of the 9955 evaluable patients was 62 +/- 12 years; 54% were male. Coronary disease and diabetes mellitus had been diagnosed in 30% and 31%, respectively, and 14% were current smokers. Current treatment consisted of a statin in 75%. The proportion of patients achieving LDL-C goals according to relevant national guidelines ranged from 47% to 84% across countries. In low-, moderate-, and high-risk groups, mean LDL-C was 119, 109, and 91 mg/dL and mean high-density lipoprotein cholesterol was 62, 49, and 50 mg/dL, respectively. The success rate for LDL-C goal achievement was 86% in low-, 74% in moderate-, and 67% in high-risk patients (73% overall). However, among coronary heart disease patients with >= 2 risk factors, only 30% attained the optional LDL-C goal of < 70 mg/dL. In the entire cohort, high-density lipoprotein cholesterol was < 40 mg/dL in 19%, 40 to 60 mg/dL in 55%, and > 60 mg/dL in 26% of patients. Conclusions-Although there is room for improvement, particularly in very-high-risk patients, these results indicate that lipid-lowering therapy is being applied much more successfully than it was a decade ago. (Circulation. 2009; 120: 28-34.)

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Background and Purpose. There has been a lot of debate about the use of predicted oxygen consumption to calculate pulmonary vascular resistance using the Fick principle. We therefore comparatively analyzed predicted oxygen consumption in infants and children in specific age groups, using different methods (formulas), as an attempt to better understand the usefulness and limitations of predictions. Methods and Results. Four models (LaFarge & Miettinen, Bergstra et al., Lindahl, and Lundell et al.) were used to predict oxygen consumption in 200 acyanotic patients with congenital cardiac defects aged 0-2.0, > 2.0-4.0, > 4.0-6.0, and > 6.0-8.75 years (median 2.04 years). Significant differences were observed between the age groups (P < .001) and between the methods (P < .001), not related to diagnoses. Differences between methods were more impressive in the first age group (P < .01). In patients aged 0-2.0 years, the lowest values of oxygen consumption (corresponding to the highest estimates of pulmonary vascular resistance) were obtained with the method of Lindahl; above this age, any method except that of Lundell et al. Conclusions. Although measuring oxygen consumption is always preferable, a rational use of predictions, using different methods, may be of help in situations where measurements are definitely not possible.

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The purpose of the present substudy of the Lipid Treatment Assessment Project 2 was to assess dual C-reactive protein (CRP) and low-density lipoprotein (LDL) cholesterol goal attainment across a spectrum of low-, moderate-, and high-risk patients with dyslipidemia in 8 countries in North America, Latin America, Europe, and Asia. Of the 9,518 patients studied overall, 45% were women, 64% had hypertension, 31% had diabetes, 14% were current smokers, 60% were high risk, and 79% were taking a statin. The median CRP level was 1.5 mg/L (interquartile range 0.2 to 2.8). On multivariate analysis, higher CRP levels were associated with older age, female gender, hypertension, current smoking, greater body mass index, larger waist circumference, LDL cholesterol level, and triglyceride/high-density lipoprotein cholesterol ratio. In contrast, being from Asia or taking a statin was associated with lower levels. Across all risk groups, 59% of patients attained the CRP target of <2 mg/L, and 33% had <1 mg/L. Overall, 44% of patients attained both their National Cholesterol Education Program Adult Treatment Panel III LDL cholesterol target and a CRP level of <2 mg/L, but only 26% attained their LDL cholesterol target and a CRP level of <1 mg/L. In the very high-risk group with coronary heart disease and >= 2 risk factors, only 19% attained both their LDL cholesterol goal and a CRP level of <2 mg/L and 12% their LDL cholesterol goal and a CRP level of <1 mg/L. In conclusion, with current treatment, most dyslipidemic patients do not reach the dual CRP and LDL cholesterol goals. Smoking cessation, weight reduction, and the greater use of more potent statins at higher doses might be able to improve these outcomes. (C) 2011 Elsevier Inc. All rights reserved. (Am J Cardiol 2011;107:1639-1643)

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An improved method for counting virus and virus like particles by electron microscopy (EM) was developed. The procedure involves the determination of the absolute concentration of pure or semi-pure particles once deposited evenly on EM grids using either centrifugation or antibody capture techniques. The counting of particles was done with a Microfiche unit which enlarged approximately 50 x the image of particles on a developed negative film which had been taken at a relatively low magnification (2500 x) by EM. Initially, latex particles of a known concentration were counted using this approach, to prove the accuracy of the technique. The latex particles were deposited evenly on an EM grid using centrifugation (Modified Beckmen EM-90 Airfuge technique). Subsequently, recombinant Bluetongue virus (BTV) core-like particles (CLPs) captured by a Monoclonal antibody using a hovel sample loading method were counted by the Microfiche unit method and by a direct EM method. Comparison of the simplified counting method developed with a conventional method, showed good agreement. The method is simple, accurate, rapid, and reproducible when used with either pure particles or with particles from crude cell culture extracts.

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Objective: This analysis of the Lipid Treatment Assessment Project 2 population compared lipid goal attainment by diabetes and metabolic syndrome status. Research design and methods: Dyslipidaemic patients aged >= 20 years on stable lipid lowering therapy had their lipid levels determined once during enrolment at investigation sites in nine countries between September 2006 and April 2007. Achievement of low-density lipoprotein (LDL) cholesterol success, triglycerides < 150 mg/dl (1.7 mmol/l), and high-density lipoprotein (HDL) cholesterol success (> 40 mg/dl [1.0 mmol/l] in men or > 50 mg/dl [1.3 mmol/l] in women) was compared using logistic regression. Results: A total of 9955 patients were evaluated. Patients with diabetes, compared with those without diabetes, had lower achievement of LDL cholesterol goals (according to National Cholesterol Education Program Adult Treatment Panel [NCEP ATP] III guidelines; 67% vs. 75%), triglycerides < 150 mg/dl (55% vs. 64%), and HDL cholesterol success (61% vs. 74%; p < 0.0001 for all comparisons). The significantly lower lipid goal attainment in patients with diabetes was consistent across participating world regions. Patients with metabolic syndrome, compared with those without metabolic syndrome, had lower achievement of NCEP ATP III LDL cholesterol goals (69% vs. 76%), triglycerides < 150 mg/dl (36% vs. 83%), and HDL cholesterol success (49% vs. 89%; p < 0.0001 for all comparisons). As the number of metabolic syndrome components increased, lipid success rates progressively decreased (p < 0.0001 for LDL cholesterol success, triglycerides < 150 mg/dl, and HDL cholesterol success). Conclusions: This analysis indicates that despite their increased cardiovascular risk, patients with diabetes or metabolic syndrome remain undertreated.

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MCM-41 samples of various pore dimensions are synthesized. Plotting of nitrogen adsorption data at 77 K versus the statistical film thickness (comparison plot) reveals three distinct stages, with a characteristic of two points of inflection. The steep intermediate stage caused by capillary condensation occurred in the highly uniform mesopores. From the slopes of the sections before and after the condensation, the surface area of the mesopores is calculated. The linear portion of the last section is extrapolated to the adsorption axis of the comparison plot, and this intercept is used to obtain the volume of the mesopores. From the surface area and pore volume, average mesopore diameter is calculated, and the value thus obtained is in good agreement with the pore dimension obtained from powder X-ray diffraction measurements. The principle of the calculation as well as problems associated are discussed in detail.

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OBJECTIVE To evaluate the correlation between ultrasound-estimated bladder weight (UEBW) in patients with different degrees of bladder outlet obstruction (BOO). METHODS We evaluated 50 consecutive non-neurogenic male patients with lower urinary tract symptoms (LUTS) referred to urodynamic study (UDS). All patients self-answered the International Prostate Score Symptoms (IPSS) questionnaire. After the UDS, the bladder was filled with 150 mL to determine UEBW. Patients with a bladder capacity under 150 mL, a previous history of prostate surgery or pelvic irradiation, an IPSS score <8, a bladder stone or urinary tract infection were excluded. After a pressure-flow study, the Schafer linear passive urethral resistance relation nomogram was plotted to determine the grade of obstruction: Grades I-II/VI were defined as mild obstruction, Grades III-IV/VI as moderate obstruction, and Grades V-VI/VI as severe obstruction. RESULTS The UEBW was 51.7 +/- 26.9, 54.1 +/- 30.0 and 54.8 +/- 28.2 in patients with mild, moderate and severe BOO, respectively (P = 0.130). The UEBW allowed us to define four groups: (i) UEBW < 35 g; (ii) 35 g <= UEBW < 50 g; (iii) 50 g <= UEBW < 70 g; and (4) UEBW >= 70 g. We did not find any differences in age, prostate weight, IPSS, PVR, cystometric bladder capacity, presence of detrusor overactive and degree of obstruction in the aforementioned groups. CONCLUSION Despite the fact that some studies have emphasized the value of UEBW as an efficient non-invasive method for evaluating lower urinary tract obstruction, our study suggests that UEBW does not present any individual correlation with LUTS or objective measurements of BOO.

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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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Purpose: The diagnosis of prostate cancer in men with persistently increased prostate specific antigen after a negative prostate biopsy has become a great challenge for urologists and pathologists. We analyzed the diagnostic value of 6 genes in the tissue of patients with prostate cancer. Materials and Methods: The study was comprised of 50 patients with localized disease who underwent radical prostatectomy. Gene selection was based on a previous microarray analysis. Among 4,147 genes with different expressions between 2 pools of patients 6 genes (PSMA, TMEFF2, GREB1, TH1L, IgH3 and PGC) were selected. These genes were tested for diagnostic value using the quantitative reverse transcription polymerase chain reaction method. Initially malignant tissue samples from 33 patients were analyzed and in the second part of the study we analyzed benign tissue samples from the other 17 patients with prostate cancer. The control group was comprised of tissue samples of patients with benign prostatic hyperplasia. Results: Analysis of malignant prostatic tissue demonstrated that prostate specific membrane antigen was over expressed (mean 9 times) and pepsinogen C was under expressed (mean 1.3 X 10(-4) times) in all cases compared to benign prostatic hyperplasia. The other 4 tested genes showed a variable expression pattern not allowing for differentiation between benign and malignant cases. When we tested these results in the benign prostate tissues from patients with cancer, pepsinogen C maintained the expression pattern. In terms of prostate specific membrane antigen, despite over expression in most cases (mean 12 times), 2 cases (12%) presented with under expression. Conclusions: Pepsinogen C tissue expression may constitute a powerful adjunctive method to prostate biopsy in the diagnosis of prostate cancer cases.