Establishing successful long-term hemodialysis access remains a major challenge. The primary aims of this study were to determine whether primary success and primary and secondary patency rates of a series of consecutive radio-cephalic fistulae (RCF) were affected by the experience of the surgeon. The secondary aims were to assess complications, and to compare results with patency rates from the literature. All native fistulae (AVF) created in our unit between January 1, 2002 and December 31, 2005 were analyzed retrospectively. The RCF were identified and divided into group A (RCF fashioned by the consultant surgeon), and group B (fashioned by the junior surgeons within the unit). Demographic characteristics, risk factors, primary success rate (patent fistula at discharge), and primary and secondary patency rates were compared between each group using chi-squared test. During this period, 552 AVF were created. Of the 195 RCF, there were 153 fistulae in group A and 42 in group B. Median follow-up was 22 months for both groups. There was no difference with regards to age, sex ratio, prevalence of diabetes, and cardiovascular disease. The primary success rate in group A and B was 94.2% and 81%, respectively (p < 0.01). Primary and secondary patency rates at 22 months were 80%, 93%* and 74%, 81%* in group A and B, respectively (*p < 0.025). Even within group B, these results compare very favorably with the published literature. These results suggest that the placement of a RCF should be performed by the most experienced member of a team dedicated to vascular access creation or at least under his supervision.

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This paper presents the application of Water Wave Optimization Algorithm (WWOA) for solving economic dispatch problems including practical generator constraints. WWOA is inspired by the shallow water wave theory. The efficiency of the WWO Algorithm for solving economic dispatch problems is demonstrated by implementing it on three test systems having three, six and fifteen generating units with non-linear characteristics of the generator such as ramp-rate limits, prohibited operating zones including the system transmission losses. The results of the proposed approach have been compared with existing results obtained by other solution techniques. The test results reveal the capability of the proposed algorithm as an effective tool for solving various economic dispatch problems in a power system.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was whether screening an asymptomatic person with a routine chest X-ray would detect lung cancer early and, most importantly, improve that person's disease-free survival from lung cancer. Altogether 136 papers were identified using the search below. Ten papers presented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses of the papers are tabulated. We conclude that despite methodological criticisms and concerns regarding biases inherent to screening studies, there is currently no evidence to support the use of chest X-ray to screen an asymptomatic person for lung cancer.

This paper presents the Water Wave Optimization Algorithm (WWOA) for solving multi-area economic dispatch (MAED) problem with tie line constraints considering transmission losses, area demand constraints, multiple fuels options, valvepoint loading effects and prohibited operating zones. Here, the amount of power that can be economically generated in one or more areas are exchanged with other areas with deficient generation through the interconnected tie-lines while meeting out the area wise and total power demand and other constraints is formulated as the MAED problem. WWOA is one of the nature inspired algorithm which mimics the phenomena of water waves for global optimization is implemented for the solution of multi-area economic dispatch problem. The effectiveness of the proposed algorithm has been verified on three different test systems and are compared with Teaching learning based optimization (TLBO), differential evolution (DE), evolutionary programming (EP) and real coded genetic algorithm (RCGA), considering the quality of the solution obtained, and the results shows a quick convergence of the proposed algorithm and are found to be superior than the other methods in the literature and seems to be a potential alternative advancement in practical power system for solving the MAED problems. KeywordsWater wave optimization algorithm, multi-area economic dispatch, multiple fuel options, cost minimization, prohibited operating zones.