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In electric vehicle (EV) applications, hybrid excitation of switched reluctance motors (HESRMs) are gaining popularity due to their advantages over other EV motors. The benefits include control flexibility, simple construction, high torque/power density, and the ability to operate over a broad speed range. However, modern HESRMs are constructed by increasing the air gap flux density with permanent magnets (PMs) in the excitation system in order to generate more electromagnetic torque. This study aims to investigate a new topology for increasing the torque capabilities of HESRM without the use of permanent magnets (PMs) or other rare-earth components. This paper provides a comprehensive evaluation of the static and dynamic characteristics, software analysis using the Ansys 2D finite element method (FEM), and an experimental demonstration of the real-time motor with an advanced control strategy in MATLAB/Simulink. Our simulation and experimental results for a machine with 12/8 poles and a machine rating of 1.2 kW indicate that the HESRM designed without PMs has greater torque capability and efficiency than the conventional SRM. The proposed HESRM without PMs has a high torque/power density and a higher torque per ampere across the entire speed range, making it suitable for EV applications.

Background: Benign prostatic hyperplasia (BPH) is an abnormal stromal and glandular proliferation of the prostate gland and is a common benign tumor found in men above 50 years of age. Most men who reach their average expectancy will experience this condition in their life time. The amount of intra-operative and postoperative bleeding depends on the gland size, surgeon’s expertise and duration of surgery. Intraoperative bleeding is usually controlled with electro-coagulation, but excessive intra and perioperative blood loss can cause hemodynamic instability, that may increase morbidity and mortality associated with the procedure. Proliferation of the prostatic glandular tissue depends on the androgen dihydro-testosterone, hence inhibition of 5α-reductase cause’s reduction of gland volume that will indirectly reduce the duration of surgery and decrease the blood loss. Methods: The study was conducted in the Department of Urology, Katuri Medical College, Guntur, Andhra Pradesh. One hundred patients who underwent TURP for symptomatic BPH from September 2015 to December 2019 fulfilling the inclusion and exclusion criteria were included in the study. Results: They were randomized in to group A (received 2 weeks of preoperative tab. Finasteride 5 mg OD) and group B (placebo group), with a total of fifty patients in each group. In 70% of the patients in this study group, the prostatic weight was between 40 to 60 grams. 10 out of 50 patients in group A and 9 out of 50 patients in group B had prostatic weight of more than 60 grams. There is significant haemoglobin drop difference between the groups. p=0.001.it’s statistically significant. Postoperative mean haemoglobin in group A & B were 10 grams and 9.4 grams/dl respectively. Postoperative mean PCV in both group A& B were 30 and 28%. Conclusions: Pre-operative short course of finasteride therapy (Tab. finasteride 5 mg OD) definitely reduces the perioperative complications like intra and postoperative blood loss, persistent hematuria, need for blood transfusions, clot retention and postoperative voiding failure. It also decreases operative time, tissue microvessel density and post-operative UTI.

Investigating the balance of risk for thrombotic and bleeding events after percutaneous coronary intervention (PCI) is especially relevant for patients at high bleeding risk (HBR). The Academic Research Consortium for HBR recently proposed a consensus definition in an effort to standardize the patient population included in HBR trials. The aim of this consensus-based document, the second initiative from the Academic Research Consortium for HBR, is to propose recommendations to guide the design of clinical trials of devices and drugs in HBR patients undergoing PCI. The authors discuss the designs of trials in HBR patients undergoing PCI and various aspects of trial design specific to HBR patients, including target populations, intervention and control groups, primary and secondary outcomes, and timing of endpoint reporting.

We present a number of computationally cost-effective approaches to calculate magnetic excitations (i.e. crystal field energies and magnetic anisotropies in the lowest spin-orbit multiplet) in lanthanide complexes. In particular, we focus on the representation of the spin-orbit coupling term of the molecular Hamiltonian, which has been implemented within the quantum chemistry package CERES using various approximations to the Breit-Pauli Hamiltonian. The approximations include the (i) bare one-electron approximation, (ii) atomic mean field and molecular mean field approximations of the two-electron term, (iii) full representation of the Breit-Pauli Hamiltonian. Within the framework of the CERES implementation, the spin-orbit Hamiltonian is always fully diagonalized together with the electron repulsion Hamiltonian (CASCI-SO) on the full basis of Slater determinants arising within the 4f ligand field space. For the first time, we make full use of the Cholesky decomposition of two-electron spin-orbit integrals to speed up the calculation of the two-electron spin-orbit operator. We perform an extensive comparison of the different approximations on a set of lanthanide complexes varying both the lanthanide ion and the ligands. Surprisingly, while our results confirm the need of at least a mean field approach to accurately describe the spin-orbit coupling interaction within the ground Russell-Saunders term, we find that the simple bare one-electron spin-orbit Hamiltonian performs reasonably well to describe the crystal field split energies and g tensors within the ground spin-orbit multiplet, which characterize all the magnetic excitations responsible for lanthanide-based single-molecule magnetism.

Objectives\ud This study aimed to examine the 30-day unplanned readmissions rate, predictors of readmission, causes of readmissions, and clinical impact of readmissions after percutaneous coronary intervention (PCI).\ud \ud Background\ud Unplanned rehospitalizations following PCI carry significant burden to both patients and the local health care economy and are increasingly considered as an indicator of quality of care.\ud \ud Methods\ud Patients undergoing PCI between 2013 and 2014 in the U.S. Nationwide Readmission Database were included. Incidence, predictors, causes, and cost of 30-day unplanned readmissions were determined.\ud \ud Results\ud A total of 833,344 patients with PCI were included, of whom 77,982 (9.3%) had an unplanned readmission within 30 days. Length of stay for the index PCI was greater (4.7 vs. 3.9 days) and mean total hospital cost ($23,211 vs. $37,524) was higher for patients who were readmitted compared with those not readmitted. The factors strongly independently associated with readmissions were index hospitalization discharge against medical advice (odds ratio [OR]: 1.91; 95% confidence interval [CI]: 1.65 to 2.22), transfer to short-term hospital for inpatient care (OR: 1.62; 95% CI: 1.38 to 1.90), discharge to care home (OR: 1.57; 95% CI: 1.51 to 1.64), and chronic kidney disease (OR: 1.50; 95% CI: 1.44 to 1.55). Charlson Comorbidity Index score (OR: 1.28; 95% CI: 1.27 to 1.29) and number of comorbidities (OR: 1.18; 95% CI: 1.17 to 1.18) were independently associated with unplanned readmission. The majority of readmissions were due to noncardiac causes (56.1%).\ud \ud Conclusions\ud Thirty-day readmissions after PCI are relatively common and relate to baseline comorbidities and place of discharge. More than one-half of the readmissions were due to noncardiac causes.

The success of the dental treatment as perceived by our patients is often preferentially evaluated on the appearance of the restoration. Usually visual determination is unreliable and inconsistent, complicated by the inability of the shade guide to cover the entire dental color range and also there is lack of logical order of arrangement of the tabs. Hence a clinical study is planned to perform visual shade selection in standardized conditions to correlate the shades of maxillary anterior natural teeth in adult subjects of Davengere district origin to one acrylic and three porcelain shade guides commercially available in India. How to cite this article Khurana PRS, Thomas PV, Rao SV, Balamuragan R, Singh MP. A Clinical Study to Correlate Maxillary Anterior Natural Teeth with that of the Commercially Available Acrylic and Porcelain Shade Guides. J Contemp Dent Pract 2013;14(3):427-433.

Background Transradial intervention (TRI) and bivalirudin infusion compared with transfemoral coronary intervention or unfractionated heparin plus glycoprotein IIb/IIIa inhibitors decrease bleeding complications in patients with acute coronary syndromes (ACS). Although bleeding is thought to be associated with worse outcomes, it remains unclear whether TRI and bivalirudin both independently lower ischemic or combined ischemic and bleeding complications in ACS patients undergoing contemporary invasive management. Hypotheses The primary objectives of the MATRIX program are to assess whether TRI or bivalirudin as compared, respectively, with transfemoral coronary intervention (MATRIX access site) or unfractionated heparin plus provisional glycoprotein IIb/IIIa inhibitors, (MATRIX antithrombin) decrease the 30-day incidence of an ischemic (ie, death, myocardial infarction or stroke) or an ischemic and bleeding composite end point across the whole spectrum of ACS patients, including clarifying the optimal duration of bivalirudin infusion after percutaneous coronary intervention (MATRIX treatment duration). Study design The MATRIX (NCT01433627) study, which incorporates 3 randomized comparisons in a nonfactorial manner and primary end points at 30 days and clinical follow-up ≤1 year, is a large-scale, multicenter study with blind event adjudication conducted at approximately 100 European sites. With 8,200 patients in the randomized comparison of access sites and 6,800 individuals participating in the randomized comparison of antithrombin regimens, this study will have ≥85% power for the primary end points. Summary The MATRIX program aims at conclusively ascertaining the role of TRI and bivalirudin infusion in the whole spectrum of ACS patients undergoing contemporary invasive management.

In the recently published MATRIX (Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and Systemic Implementation of angioX) trial, the use of transradial access (TRA) compared to transfemoral access (TFA) during percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) was associated with a reduction in net adverse cardiovascular events. However, the results of MATRIX must be interpreted with caution due to several limitations including the strong modulating effect of operator/center experience on the relative efficacy of TRA and the inclusion of 2 distinct patient populations (ST-segment elevation and non-ST-segment elevation ACS). Therefore, although important, the results of MATRIX have strong limitations and are not sufficient to definitively identify an approach of choice during PCI for ACS. Further research is needed before strong, evidence-based recommendations regarding the approach of choice during PCI for ACS can be made.

Using the framework of a new relaxation system, which converts a nonlinear viscous conservation law into a system of linear convection-diffusion equations with nonlinear source terms, a finite variable difference method is developed for nonlinear hyperbolic-parabolic equations. The basic idea is to formulate a finite volume method with an optimum spatial difference, using the Locally Exact Numerical Scheme (LENS), leading to a Finite Variable Difference Method as introduced by Sakai [Katsuhiro Sakai, A new finite variable difference method with application to locally exact numerical scheme, journal of Computational Physics, 124 (1996) pp. 301-308.], for the linear convection-diffusion equations obtained by using a relaxation system. Source terms are treated with the well-balanced scheme of Jin [Shi Jin, A steady-state capturing method for hyperbolic systems with geometrical source terms, Mathematical Modeling Numerical Analysis, 35 (4) (2001) pp. 631-645]. Bench-mark test problems for scalar and vector conservation laws in one and two dimensions are solved using this new algorithm and the results demonstrate the efficiency of the scheme in capturing the flow features accurately.

A numerical method in which the Rankine-Hugoniot condition is enforced at the discrete level is developed. The simple format of central discretization in a finite volume method is used together with the jump condition to develop a simple and yet accurate numerical method free of Riemann solvers and complicated flux splittings. The steady discontinuities are Captured accurately by this numerical method. The basic idea is to fix the coefficient of numerical dissipation based on the Rankine-Hugoniot (jump) condition. Several numerical examples for scalar and vector hyperbolic conservation laws representing the inviscid Burgets equation, the Euler equations of gas dynamics, shallow water equations and ideal MHD equations in one and two dimensions are presented which demonstrate the efficiency and accuracy of this numerical method in capturing the flow features.

Non-standard finite difference methods (NSFDM) introduced by Mickens [Non-standard Finite Difference Models of Differential Equations, World Scientific, Singapore, 1994] are interesting alternatives to the traditional finite difference and finite volume methods. When applied to linear hyperbolic conservation laws, these methods reproduce exact solutions. In this paper, the NSFDM is first extended to hyperbolic systems of conservation laws, by a novel utilization of the decoupled equations using characteristic variables. In the second part of this paper, the NSFDM is studied for its efficacy in application to nonlinear scalar hyperbolic conservation laws. The original NSFDMs introduced by Mickens (1994) were not in conservation form, which is an important feature in capturing discontinuities at the right locations. Mickens [Construction and analysis of a non-standard finite difference scheme for the Burgers–Fisher equations, Journal of Sound and Vibration 257 (4) (2002) 791–797] recently introduced a NSFDM in conservative form. This method captures the shock waves exactly, without any numerical dissipation. In this paper, this algorithm is tested for the case of expansion waves with sonic points and is found to generate unphysical expansion shocks. As a remedy to this defect, we use the strategy of composite schemes [R. Liska, B. Wendroff, Composite schemes for conservation laws, SIAM Journal of Numerical Analysis 35 (6) (1998) 2250–2271] in which the accurate NSFDM is used as the basic scheme and localized relaxation NSFDM is used as the supporting scheme which acts like a filter. Relaxation schemes introduced by Jin and Xin [The relaxation schemes for systems of conservation laws in arbitrary space dimensions, Communications in Pure and Applied Mathematics 48 (1995) 235–276] are based on relaxation systems which replace the nonlinear hyperbolic conservation laws by a semi-linear system with a stiff relaxation term. The relaxation parameter (λ) is chosen locally on the three point stencil of grid which makes the proposed method more efficient. This composite scheme overcomes the problem of unphysical expansion shocks and captures the shock waves with an accuracy better than the upwind relaxation scheme, as demonstrated by the test cases, together with comparisons with popular numerical methods like Roe scheme and ENO schemes.

Conjugate natural convection in a vertical annulus with a centrally located vertical heat generating rod is studied numerically. The governing equations are discretized on a staggered mesh and are solved using a pressure-correction algorithm. A parametric study is performed by varying the Grashof number, aspect ratio, and the solid-to-fluid thermal conductivity ratio over wide ranges with the Prandtl number fixed at 0.7. Results are presented for the variation of several quantities of interest such as the local Nusselt numbers on the inner and outer boundaries, the axial variation of the centerline and interface temperatures, maximum solid, average solid and average interface temperature variations with Grashof number, and the average Nusselt number variation for the inner and outer boundaries with Grashof number. The average Nusselt number from the conjugate analysis is found to be between the Nusselt numbers of the isothermal and the isoflux cases. The average Nusselt numbers on the inner and outer boundaries show an increasing trend with the Grashof number. Correlations are presented for the Nusselt number and the dimensionless temperatures of interest in terms of the parameters of the problem.

We have presented a new low dissipative kinetic scheme based on a modified Courant Splitting of the molecular velocity through a parameter φ. Conditions for the split fluxes derived based on equilibrium determine φ for a one point shock. It turns out that φ is a function of the Left and Right states to the shock and that these states should satisfy the Rankine-Hugoniot Jump condition. Hence φ is utilized in regions where the gradients are sufficiently high, and is switched to unity in smooth regions. Numerical results confirm a discrete shock structure with a single interior point when the shock is aligned with the grid.

Cardiovascular diseases are the emerging causes of the mortality which is looming large in India also. Particularly, the Indian populations are genetically more susceptible to them [1]. Dyslipidaemia (especially high LDL-C levels) is the promoter of atherosclerosis, whereas the HDL-C fraction is protective [2]. The oxidatively modified LDL associated conversion of macrophages to foam cells is reportedly atherogenic [3]. The pro-inflammatory oxidative milieu favours this process [4]. The dyslipidaemia associated acute phase response was shown to develop a pro-inflammatory state which promoted atherosclerosis [5, 6]. The usual practice of assaying the entire lipid profile may not be cost effective for predicting the cardiovascular risk burden. Oxidized-LDL and/or malondialdehyde modified-LDL, appear as informative markers [7]. However, technically, they do not appear to be suitable for a routine clinical laboratory setting. Hence, there is an ardent need of reasonably effective and affordable tests. In this study, the plasma lipid profile parameters, namely HDL-C (high density lipoprotein), LDL-C (low density lipoprotein), TG (triglyceride) and TC (total cholesterol) were assessed in both myocardial infarction (MI) cases and in healthy controls; each parameter was correlated with the lipid peroxidative parameter, MDA to find out any possible single parameter which was most closely associated with its oxidative pathology, so as to draw any meaningful association for prognostic purposes. A case cohort was formed by selecting 42 clinically as well as electrocardiographically confirmed and previously untreated cases of MI (median age 58 years). Diabetes Mellitus, or any other major diseases and a past history of smoking were ruled out. Similarly, an age and sex matched cohort was formed by selecting 38 healthy volunteers from among the hospital staff (median age 54 years). Plasma samples were collected from all the individuals of both the groups after taking informed consents from them. The patients’ samples were collected within 12 hours of their admissions. Their lipid profiles, along with the direct LDL measurements, were assessed by using commercial kits as per the manufacturer’s protocol. The MDA estimation was done by a spectrophotometric method [8]. Except for HDL-C which was found to be significantly low in the cases, the mean levels of the lipid profile parameters in the cases were significantly high as compared to those in the corresponding control group; the MDA levels were also found to be significantly high among the cases [Table/Fig-1]. This showed a marked dyslipidaemia in the patient populace. Pearson’s correlation analysis showed a high degree of positive correlation between MDA and TC and also with LDL cholesterol (r = 0.79 and 0.72 respectively) in the MI cases. The positive correlation between MDA and the TG level was not comparably high. Similarly, the negative correlation between HDL-C and the MDA level was also not very significant. The control group parameters did not show any significant correlations. This result conformed to the view of the oxidative pathology being associated with such metabolic abnormalities. Total cholesterol and LDL-C, being significantly associated with lipid peroxidation in the cases, suggested a direct contribution of these fractions in the pathogenesis. However, in the general practice, LDL-C is calculated from the Friedwald’s formula and it may thus incorporate considerable error [9]. Moreover, the highest correlation value was observed between total cholesterol and MDA. This finding corroborated with that of an earlier study which reported a relative risk predictive efficacy of TC, which showed its direct association with the mortality in coronary heart disease [10, 11]. Hence, with the perspective of this small scale pilot type study (considering the huge prevalence of cardiovascular diseases in the general population), total cholesterol alone, as a single parameter, demands a large-scale multi-centric trial for being considered as an effective and an economic option for the prediction of the severity of cardiovascular health hazards in the MI cases. [Table/Fig-1]: Comparative display of lipid Profile parameters and malondialdehyde (MDA) in MI patients and control groups