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This paper proposes a hill-climbing maximum power point tracking (MPPT) algorithm for a stand-alone self-excited induction generator (SEIG)-based wind energy conversion system (WECS) feeding an Induction Motor (IM) pump. The proposition involves a single voltage source converter (VSC) for power conditioning and MPPT. Secondly, the proposed MPPT algorithm is one of its kind, employing a feed-forward hill-climbing algorithm with the operating frequency of the VSC as a control variable, thus improving the overall system stability. In addition, the algorithm uses only current and voltage sensors, making it speed sensorless and comprehensive. Besides effective MPPT, the constant flux operation of the SEIG and the IM pump are ensured for the entire operating range. The effective operation and control of the proposed algorithm is successfully demonstrated against wind velocity and load variations using simulation and experimental results. The proposition forms robust, low-complex and economic solution for MPPT of WECS for deployment in remotely located stand-alone applications. [ABSTRACT FROM AUTHOR]

A numerical investigation on MHD fluid flow in parabolic mode has been performed to point out its significant properties. Thermal radiation, porous medium, heat generation, chemical reaction, and thermal diffusion along with variable temperature and concentration are taken into consideration in the analysis. The novelty of the work is the inclusion of heat generation and thermal diffusion along with exponentially varying temperature and concentration. The constituent governing equations are solved by using finite difference schemes in explicit form. The fluctuations in velocity, concentration, and temperature are observed and discussed with the help of graphs as well as numerical data. Their gradients are also calculated and analyzed the flow properties by using numerical tables. The existence of heat generation, as well as viscous dissipation, creates an increment in the temperature. The gradient of heat transfer rises with the impact of Prandtl number and decay in it is examined under the existence of a source of heat and viscous dissipation. [ABSTRACT FROM AUTHOR]

Introduction: The impact of Ramadan fasting in patients with chronic kidney disease (CKD) remains less studied and with inconsistent results. In this study, we tried to look at the impact of Ramadan fasting on renal function in patients with CKD. Materials and Methods: In this prospective observational study, we included 28 adult CKD patients. All relevant biochemical parameters including renal function tests were done in the month before Ramadan fasting and within 3 months after Ramadan. Urine output, body weight, and blood pressure were also monitored during Ramadan and after the end of Ramadan for at least 10 days. Results: All the 28 patients (mean age: 46 ± 12 years) included in the study managed to fast for the whole month, and none displayed any new clinical symptoms or signs. The renal function worsened in four (14.28%), and it was significant in those with CKD Stages 4 and 5 (P < 0.003). Conclusion: Stable CKD patients can fast with careful monitoring; however, there is a risk of renal function deterioration in advanced CKD. [ABSTRACT FROM AUTHOR]

Glomerular diseases are one of the most challenging entities in terms of diagnosis and management, especially when associated with systemic illnesses such as malignant disorders. Herein, a case of crescentic glomerulonephritis (CrGN) associated with polycythaemia vera (PV) in a 50-year-old female is described. She presented with bilateral pedal oedema, splenomegaly, renal dysfunction and severe proteinuria. On evaluation, we found PV and CrGN. Renal involvement in PV is rare and generally considered as a manifestation of hypervolemia or high-viscosity-induced renal hyper-perfusion and hyper-filtration. This is a unique case of immunologically-mediated renal disease in PV. [ABSTRACT FROM AUTHOR]

Summary: This article proposes a standalone hybrid wind‐photovoltaic (PV) water pumping system (WPS) with minimal power electronics interface, simple composite control, and optimal energy management strategy (EMS) for effective utilization of both renewable sources. The proposed system consists of classic Perturb and Observe (P&O) algorithm applied to the boost converter of the solar PV system and voltage regulation algorithm/hill‐climbing MPPT algorithm with zero steady‐state oscillation (ZSSO) applied to bidirectional voltage source converter (VSC) of wind energy conversion systems (WECS) for optimal power extraction at all times. The constant voltage to frequency (V/F) ratio is ensured at the point of common coupling (PCC) for the entire operating range to avoid saturation in the self‐excited induction generator (SEIG) and the induction motor (IM) pump. The energy management strategy is devised to effectively harness renewable energy from both sources while ensuring the DC‐link voltage stability. The system forms compelling proposition, given the least converter count to integrate solar‐PV and wind energy employing easy to implement control algorithms with optimal energy extraction. The results of simulation and experimental studies on the proposed system reveal the effectiveness of the composite controller in terms of energy utilization, constant flux operation, and power balance for the entire operating range. Additionally, system exhibits acceptable dynamic and steady‐state behavior against variations in wind velocity, solar irradiation, and load. [ABSTRACT FROM AUTHOR]

The use of BCG in immunotherapy for bladder cancer has been in practice for over 40 years. However, uncommon, serious complications can occur with the therapy. Here, we present a case of vertebral osteomyelitis secondary to dissemination of BCG following immunotherapy, an exceedingly rare presentation of an already rare complication. [ABSTRACT FROM AUTHOR]

Abstract: The repeated low-velocity impact responses of hybrid plain-woven composite panels were studied by drop-weight experiments. Non-hybrid S2-glass-fiber/toughened epoxy and IM7 graphite fiber/toughened epoxy as well as hybrid S2-glass–IM7 graphite fiber/toughened epoxy composite panels were impacted repeatedly using a pressure-assisted Instron-Dynatup 8520 instrumented drop-weight impact tester. During the low-velocity impact tests, the time histories of impact forces, absorbed impact energies and panel central deflections were recorded. The relations between the impact force and central deflection, whose slope represented the dynamic contact stiffness, were then constructed. The damaged specimens were inspected visually and using the ultrasonic C-Scan method. The effects of hybridization and lay-up sequence on the repeated drop-weight impact responses of woven composites were investigated. It was observed that damage accumulations could be slowed down using hybridization. It was also witnessed that the lay-up configuration of a hybrid composite had a significant influence on damage accumulation rate. The hybrid specimens with glass–epoxy skins survived the double number of successive impacts compared to hybrid specimens with graphite–epoxy skins. [Copyright &y& Elsevier]

Abstract: A combined experimental and 3D dynamic nonlinear finite element (FE) approach was adopted to study damage in composite beams subject to ballistic impact using a high-speed gas gun. The time-histories of dynamic strains induced during impact were recorded using strain gages mounted on the front of the composite beam specimen. During ballistic impact tests, the impact velocity was also measured. The commercially available 3D dynamic nonlinear FE code, LS-DYNA, modified with a proposed user-defined nonlinear-orthotropic damage model, was then used to simulate the experimental results. In addition, LS-DYNA with the Chang–Chang linear-orthotropic damage model was also used for comparison. Good agreement between experimental and FE results was found from the comparisons of dynamic strain and damage patterns. Once the proposed nonlinear-orthotropic damage model was verified by experimental results, further FE simulations were conducted to predict the ballistic limit velocity (V 50) using either the number of damaged layer approach or a numerically established relation between the projectile impact velocity versus residual velocity or energy similar to the classical Lambert–Jonas equation for metals. [Copyright &y& Elsevier]

The electrochemical act of valve-regulated lead acid batteries can be enhanced by conductive materials like metal oxides. This work aims to examine the preparation and influence of zirconia on poly(vinyl alcohol) based gel valve-regulated lead acid battery. Characterizations like Fourier transform infrared spectroscopy, ionic conductivity, water retention study, cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge-discharge techniques were done. The optimized gel system exhibited a discharge capacity of 198.45 μAh cm -2  at the current density of 0.6 mA cm -2 . The battery cell with an optimized gel matrix displayed a maximum discharge capacity of 22.5 μAh at a current of 20 μA. After 500 continuous cycles, the battery attained a discharge capacity retention of 91 %. The presence of zirconia will increase the electrochemical performance of gel valve-regulated lead acid batteries., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

The gel electrolyte significantly influences gel valve-regulated lead acid battery performance. To address this, the paper describes the preparation of novel polymer gel electrolytes using poly (vinyl alcohol) (PVA) and tetraethylorthosilicate (TEOS) for valve-regulated lead-acid batteries. FTIR technique is used to confirm the chemical reaction between PVA and TEOS. Electrochemical analyses such as cyclic voltammetry and electrochemical impedance spectroscopy were applied to optimize the concentration of PVA-TEOS polymer gel electrolyte. The optimum concentration of polymer gel electrolyte was determined as 20 wt% of TEOS in PVA (PE-1) with higher anodic peak and lower Rs and Rct values. The Galvanostatic charge-discharge tests were performed on the optimized gel system prototype battery. The highest capacity of 6.86 × 10 -5 Ah at a current density of 0.2 mA cm -2 was achieved with an excellent capacity retention ratio of 85.7% over 500 cycles. The exceptional cycle performance and high capacity make PVA-TEOS gel electrolyte a promising candidate for practical battery application.