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Abstract: The concept of windmill brake state model is considered in this paper. Blade Element Momentum (BEM) calculation often calculates the value of thrust coefficient in windmill brake state. Unfortunately, thrust coefficient predicted by momentum theory deviated dramatically from the experimental data when the value of axial induction factor is greater than 0.5. To solve this problem and to increase the accuracy of the prediction, windmill break state model including tip loss effect must be applied to equations of thrust coefficient. The problem of interest is that which windmill break state model is suitable for the wind turbine model being simulated. The purpose of this paper is to compare the rotor power predicted by six different windmill brake state models. The aerodynamic code based on BEM theory has been implemented in Matlab and validated with the simulated result of AWT-27 wind turbine model reported by National Renewable Energy Laboratory (NREL). Six windmill brake state models to be compared are Glauert’s characteristic equation, classical brake state model, advanced brake state model, Wilson and Walker model, modified advanced brake state model, and Shen’s correction. The predicted power curves obtained from each windmill brake state model are compared to the measured power curve of AWT-27/P4. It has been shown that Shen’s correction gives the highest correlation to the measured data with r-square of 0.970 and the predicted annual energy production (AEP) is different from measured data by only 6.3%. [Copyright &y& Elsevier]

Abstract: Acute pancreatitis (AP) is an inflammatory disease characterized by tissue edema, necrosis and hemorrhage. The mortality rate associated with this disease is particularly high when the inflammation has become systemic. Recently, activation of the pancreatic renin-angiotensin system (RAS) was shown to play a role in AP. The present study investigated whether administering an AT1 receptor antagonist decreases the severity of AP and pancreatitis-induced systemic inflammation, particularly pulmonary injury. Rats with AP-associated lung injury were induced by multiple doses of caerulein, which was demonstrated in the previous studies. Three injections of losartan (200 μg/ kg/h) were given 30 min prior to the first injection of caerulein. The results demonstrated that caerulein injections resulted in significant increases in pancreatic and pulmonary myeloperoxidase (MPO) activities, and losartan treatment attenuates these effects. Lung microvascular permeability was also significantly improved by losartan treatment. Losartan prevented caerulein-induced pancreatic and pulmonary morphological alterations, but not elevations in serum α-amylase or pancreas/body weight ratio. These data indicate that losartan treatment can attenuate pancreatic and lung injury. Thus, the implication is that a blockade of AT1 receptors may have a clinical application for the treatment of AP and, perhaps more importantly, subsequent pulmonary complications. [Copyright &y& Elsevier]

Decision makers, i.e. policy-makers and farmers, are challenged with the responsibility of planning and conducting aquaculture development in a sustainable way whereby social, environmental and economic goals are simultaneously satisfied. This paper presents a multi- criteria decision making (MCDM) model developed for the purpose of evaluating the sustainable development of shrimp farming in the northwest region of Mexico (States of Sonora, Sinaloa and Nayarit) based on the stated government objectives for aquaculture development in Mexico. Three possible production systems for two species were investigated for the planning scenario where managers seek to determine the optimal combination of new shrimp farms within 22,500 ha over a five-year period. The planning objectives assumed in the MCDM model are employment (E), foreign exchange earnings (XG), economic rent (ER) maximization, and total pollution (TOTALPOLL) minimization, subject to land availability and local market demand constraints. Under a preliminary evaluation of single-objective optimization, XG and ER maximization produce similar results. The MCDM model was implemented using Feasible Goals®, and shows that when fully allocating the available land, the shrimp farming industry would generate 7,490 new jobs, ER and XG of USD$ 68.1 and $497.6 million respectively, with a total pollutant discharge of 2,000 tons in 2005. The multiple-criteria optimization strongly favors semi-intensive systems (93% of the total 466 new farms). The sustainable development of the industry based on the assumptions of this analysis does not suggest intensification of systems. Rather, the results of the MCDM analysis support the claim that semi-intensive farms, which are more common in Mexico, promote sustainability. [ABSTRACT FROM AUTHOR]

An abstract of the article "Selective beta1-blockade improves cardiac function and energy metabolism and increases expression of myocardial angiotensinogen in rats during early postinfarct remodeling," by E. Omerovic et al., is presented.

Abstract: Three protective coatings (TiAlCr coating, TiAlN+Al2O3 and TiAlYN/CrN+Al2O3) were deposited on a Ti–45Al–8Nb alloy and exposed at 750°C for oxidation test for 5000h. The materials with Al2O3 top coat showed much better resistance than TiAlCr coating where mainly TiO2 and Al2O3 phases developed. The corrosion kinetics were determined by means of discontinuous gravimetry. The exposed samples were characterised using SEM, EDS and XRD. Artificial neural network was used to predict the kinetic behaviour of the exposed alloys after 2000–4000h of exposure. The predicted kinetic after 5000h shows good agreement with the experimental data. [Copyright &y& Elsevier]

Abstract: The output power of a wind energy conversion system (WECS) is maximized if the wind rotor is driven at an optimal rotational speed for a particular wind speed. To achieve this, a Maximum Power Point Tracking (MPPT) controller is usually used. A successful implementation of the MPPT controller requires knowledge of the turbine dynamics and instantaneous measurements of the wind speed and rotor speed. To obtain the optimal operating point, rotor-generator characteristics should be known and these are different from one system to another. Therefore, there is a need for an efficient universal MPPT controller for WECS to operate without predetermined characteristics. MPPT control of WECSs becomes difficult due to fluctuation of wind speed and wind rotor inertia. This issue is analyzed in the paper, and an Adaptive Filter together with a Fuzzy Logic based MPPT controller suitable for small-scale WECSs is proposed. The proposed controller can be implemented without predetermined WECS characteristics. [Copyright &y& Elsevier]

Abstract: Expression of the multi-PDZ protein Pdzd2 (PDZ domain-containing protein 2) is enriched in pancreatic islet β cells, but not in exocrine or α cells, suggesting a role for Pdzd2 in the regulation of pancreatic β-cell function. To explore the in vivo function of Pdzd2, Pdzd2-deficient mice were generated. Homozygous Pdzd2 mutant mice were viable and their gross morphology appeared normal. Interestingly, Pdzd2-deficient mice showed enhanced glucose tolerance in intraperitoneal glucose tolerance tests and their plasma insulin levels indicated increased basal insulin secretion after fasting. Moreover, insulin release from mutant pancreatic islets was found to be twofold higher than from normal islets. To verify the functional defect in vitro, Pdzd2 was depleted in INS-1E cells using two siRNA duplexes. Pdzd2-depleted INS-1E cells also displayed increased insulin secretion at low concentrations of glucose. Our results provide the first evidence that Pdzd2 is required for normal regulation of basal insulin secretion. [Copyright &y& Elsevier]

Abstract: Early-trimester human fetal pancreas is a promising potential source of pancreatic progenitor cells. However, the ethical controversy associated with the source of these cells, and technical difficulties associated with their differentiation into insulin-producing cells have limited both their availability and utility. This study aimed to characterize a population of pancreatic progenitor cells (PPCs) isolated from human fetus and describe the effects of a novel factor, PDZ-domain containing-2 (PDZD2), and its secreted form (sPDZD2), on PPC proliferation and differentiation. In particular, we examined and characterized the expression of several stem cell (nestin, ABCG2, c-kit), growth and differentiation markers (GLP-1R, c-met, erbB1), and PDZD2 in PPCs by RT-PCR, Western blot, and immunocytochemistry. We also examined the effects of sPDZD2 on PPC proliferation and differentiation by examining BrdU incorporation, MTT, cell number, and real-time PCR as well as ELISA. PPCs were isolated, cultured and characterized from human fetal pancreas. PDZD2 and sPDZD2 were detected at high levels in both human fetal pancreas and in PPCs. sPDZD2 acted as a potent mitogen on PPCs, and inhibited the differentiation of PPC-derived islet-like cell-clusters (ICCs), evidenced by the downregulation of Isl-1, Pdx-1, and insulin mRNA levels. sPDZD2 treatment also reduced levels of C-peptide in ICCs. These results show that a novel pancreatic developmental factor, PDZD2, is sufficient to promote the proliferation of human fetal PPCs while limiting differentiation of ICCs into islet/endocrine cells. Findings from this study will contribute to the development of improved methods for islet transplantation therapy in the treatment of diabetes. [Copyright &y& Elsevier]