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© Springer Nature Switzerland AG 2020. The renewable energy market has increased significantly over the last decade, and the solar photovoltaic (PV) power generation is becoming important in many countries globally with a particular interest in the field of distributed electric power generation. A regular and accurate examination and evaluation of the photovoltaic system performance and efficiency are very essential in the sense that they provide vital information of the system’s quality evaluation for the users, installers, as well as the manufacturers. The maximum power point of a solar panel varies with the irradiation and temperature and the control algorithms are commonly used for the maximization of the power extraction from PV arrays known as maximum power point tracking (MPPT) algorithms. Perturb and Observe (P&O) algorithm is one of the popular techniques frequently used due to its easy implementation and low cost. The MPPT technique is mainly used for obtaining the maximum power from the solar PV module and conversion circuit to the load and improving the power quality of PV power generation for grid connection. Perturb and Observe maximum power point tracking (MPPT) is extensively used in charge controllers for extracting maximum power from photovoltaic (PV) module irrespective of irradiance, temperature and load variation. The standard P&O MPPT technique has drawbacks bordering on fast convergence time to a maximum power point, poor system response to fast-changing irradiance and steady-state oscillation with a fixed step size. This chapter discusses the detailed operation and implementation of an improved P&O algorithm technique to resolve the various challenges of the standard P&O algorithm. This technique segments the operational region of the PV array into four operating sectors based on the sector location from the maximum power point (MPP), step size modifications are implemented. Furthermore, the critical comparison is made between the new P&O method and the standard P&O method. Finally, the hardware implementation of both MPPT algorithms is discussed in order to evaluate their performance and efficiency. The measured results show that the average efficiency of the proposed system is 96.89% which is more than 4% higher than the standard system.

This cross-sectional descriptive study was done to analyse the current trends of using antimicrobials in various surgical procedures at Obstetrics and Gynaecology department in Mymensingh Medical College Hospital, Mymensingh from July 2014 to June 2015. Among 300 postoperative obstetrics and gynaecological surgery cases, samples were selected as non-random purposive selection method where pattern of using antimicrobials were analysed by SPSS method 20.1 versions. The incidence of antimicrobial resistance is on continued rise with a threat to return to the pre-antibiotic era. This has led to emergence of such bacterial infections which are essentially untreatable by the current armamentarium of available treatment options. Now-a-days variation of choosing antibiotic are quietly accepted in Obstetrics and Gynaecology department as prophylaxis purpose to control life threatening conditions such as postoperative wound infection, septicaemia, urinary tract infection etc. The data analysis revealed that among 300 obstetrical and gynaecological surgeries, Nitroimidazoles (93.33%), Cephalosporins (91%) and Aminoglycosides (59%) group were most commonly used antimicrobials in both obstetrics and gynaecological surgeries. Metronidazole (93.33%), Ceftriaxone (68.66%), Gentamicin (60.33%), Cefuroxime (48%), Flucloxacillin (42%), Cefixime (27%) were the most commonly used antimicrobials at obstetrics and gynaecology department. Combination of Ceftriaxone, Metronidazole and Gentamicin (37.66%), Ceftriaxone and Metronidazole (25.33%), Cefuroxime, Metronidazole and Gentamicin (16%), Ciprofloxacin, Metronidazole and Gentamicin (5.33%) were most commonly used antimicrobials postoperatively. Total mean duration of antimicrobial therapy was 10.45 days. Antibiotics are useful in prevention of infection. But indiscriminately use of antibiotics without any guideline may lead to antimicrobial resistance. So, antimicrobial surveillance committee should be formed by hospital authority to know the local using pattern of antibiotics.

International audience; Reports unraveling the beneficial effects of Viscum album (VA) preparations as complementary therapies for cancer have increasingly revealed the underlying molecular and cellular mechanisms, which encompass cytotoxic properties, induction of apoptosis, inhibition of angiogenesis and several other immunomodulatory mechanisms. In addition to their propitious relevance to cancer therapy, VA preparations are also relevant for the treatment of several inflammatory pathologies. In view of the intricate association of inflammation and cancer and the fact that several anti-tumor phytotherapeutics exert potent anti-inflammatory effects, we believe that an anti-inflammatory effect is responsible for the therapeutic benefits of VA preparations. One of the underlying molecular mechanisms of this inflammatory response is the selective down-regulation of the cyclo-oxygenase (COX)-2-mediated cytokine-induced secretion of prostaglandin E2 (PGE2). This inhibitory action has been associated with reduced expression of COX-2, without modulating COX-1 expression. This mechanism is associated with VA-induced destabilization of COX-2 mRNA, thereby depleting the functional COX-2 mRNA available for protein synthesis and for subsequent induction of secretion of PGE2. Together, these results demonstrate a novel anti-inflammatory mechanism of action of VA preparation, wherein VAQUSpez an anti-inflammatory effect by inhibiting cytokine-induced PGE2 via selective inhibition of COX-2 and destabilization of COX-2 mRNA.

We call a depth-4 formula C set-depth-4 if there exists a (unknown) partition (X_1,...,X_d) of the variable indices [n] that the top product layer respects, i.e. C(x) = \sum_{i=1}^k \prod_{j=1}^{d} f_{i,j}(x_{X_j}), where f_{i,j} is a sparse polynomial in F[x_{X_j}]. Extending this definition to any depth - we call a depth-Delta formula C (consisting of alternating layers of Sigma and Pi gates, with a Sigma-gate on top) a set-depth-Delta formula if every Pi-layer in C respects a (unknown) partition on the variables; if Delta is even then the product gates of the bottom-most Pi-layer are allowed to compute arbitrary monomials. In this work, we give a hitting-set generator for set-depth-Delta formulas (over any field) with running time polynomial in exp(({Delta}^2 log s)^{Delta - 1}), where s is the size bound on the input set-depth-Delta formula. In other words, we give a quasi-polynomial time blackbox polynomial identity test for such constant-depth formulas. Previously, the very special case of Delta=3 (also known as set-multilinear depth-3 circuits) had no known sub-exponential time hitting-set generator. This was declared as an open problem by Shpilka & Yehudayoff (FnT-TCS 2010); the model being first studied by Nisan & Wigderson (FOCS 1995). Our work settles this question, not only for depth-3 but, up to depth epsilon.log s / loglog s, for a fixed constant epsilon < 1. The technique is to investigate depth-Delta formulas via depth-(Delta-1) formulas over a Hadamard algebra, after applying a `shift' on the variables. We propose a new algebraic conjecture about the low-support rank-concentration in the latter formulas, and manage to prove it in the case of set-depth-Delta formulas., 22 pages

Multiple abnormalities have been reported in the setting of human heart failure. It is unclear whether detected changes reflect adaptive alterations in myocardium subjected to increased and sustained hemodynamic overload or are pathogenic to the disease process. As a result of the observation that the primary defect in heart failure is decreased pump function, investigators have concentrated their efforts on determining systolic [Ca2+]i as a logical corollary and a causative mechanism for contractile dysfunction. A simple cause and effect relationship has therefore been proposed with regard to contractile dysfunction and [Ca2+]i. Yet some investigators have found no difference in peak systolic [Ca2+]i between failing and non-failing human myocardium, whereas others have found peak [Ca2+]i to be significantly reduced in failing hearts. Resting calcium concentrations have been reported either to be elevated in failing human myocardium or not different from non-failing human myocardium. Investigators should now appreciate that the force-calcium relationship is not a simple relationship. One must take into account the prolonged time course and slowed mobilization of [Ca2+]i as opposed to simply peak [Ca2+]i. When put in perspective of mechanisms and determinants of the Ca(2+)-force relationship, we begin to realize that failing human myocardium has the "potential" to generate normal levels of force. Only when stressed by [Ca2+]i overload and/or frequency perturbation does myocardium from patients with end-stage heart disease demonstrate contractile failure. Although [Ca2+]i availability and mobilization are likely to play a role in the systolic as well as diastolic dysfunction reported in human heart failure, it is likely that other mechanisms are involved as well (e.g., myocardial energetics). Myocardial energetics is directly related to [Ca2+]i and mobilization in failing human myocardium, because metabolites, e.g., ADP, inhibit pumps, such as sarcoplasmic reticulum Ca2+ ATPase activity. We therefore conclude that there is a role for intracellular calcium mobilization and myocardial energetics for systolic and diastolic dysfunction seen in human heart failure.

Now-a-days, numbers of simulation software are being used all over the world to solve Computational Fluid Dynamics (CFD) related problems. In this present study, a commercial CFD simulation software namely STAR-CCM+ is applied to analyze the airflow characteristics inside a 2.5" hard disk drive. Each step of the software is described adequately to obtain the output and the data are verified with the theories to justify the robustness of the simulation outcome. This study gives an insight about the accuracy level of the CFD simulation software to compute CFD related problems although it largely depends upon the computer speed. Also this study will open avenues for further research., {"references":["John D. Anderson Jr., Jooris Degroote Gerad Degrez, Erik Dick, Roger\nGrundmann, and Jan Vierendeels, \"Computional Fluid Dynamics: An\nIntroduction,\" Berlin Heidelberg: Springer-Verlag.","Paul Deed, and Paul Edmondson, \"What is Bernoulli's Equation and Its\nApplications,\" www.hubpages.com: http://hubpages.com/hub/What-is-\nBernoullis-Equation-and-its-applications, Retrieved April 18, 2010.","CD-adapco, \"STAR-CCM+ version 4.02.007user's guide,Singapore,\"\nSingapore: CD-adapco,2009.","William Ding, and Manish Kumar,\" Hard disk drives recirculation filter\ndesign by simulating particle and operation parameters effects on\nparticle trajectories,\" Bloomington, Donaldson Co. Inc, 2007.","Hanbing Song, Damodaran Murali, and Quock Y. Ng, \"Simualtion of\nflow field and particle trajectories in hard disk drive enclosures,\"\nMassachusetts: DSpace@MIT, 2004."]}