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Background: In kidney transplantation, concerns have been raised regarding increased incidence of viral opportunistic infections in hepatitis C virus (HCV) nucleic acid test (NAT)‐negative (‐) recipients who received HCV NAT‐positive (+) donor kidneys, specifically BK polyomavirus (BKPyV), cytomegalovirus (CMV), and Epstein‐Barr virus (EBV). The purpose of this study was to determine the incidence of these three viral opportunistic infections in HCV NAT‐ recipients who have undergone kidney transplantation with HCV NAT+ donor kidneys at our institution. Methods: This was an Institutional Review Board‐approved, single‐center, retrospective case‐control study of HCV NAT‐ kidney transplant recipients with HCV NAT+ donors from 2018 to 2021. The primary outcome was the cumulative incidence of viral infections of BKPyV, CMV, and/or EBV within 1 year following kidney transplantation. Results: A total of 231 patients were included, 77 in the exposed (donor HCV NAT+) group and 154 in the control (donor HCV NAT‐) group. The adjusted cumulative incidence of viremia within 1 year did not statistically differ between groups (77% exposed group versus 66% for the control group, hazard ratio 1.34, 95% confidence interval 0.95–1.89). In addition, no statistically significant differences were observed for secondary outcomes with the exception of CMV viremia (62% exposed versus 49% control, p = 0.021). However, there were more patients in the exposed group at high risk for CMV viremia based on serostatus (CMV Donor+/Recipient‐, D+/R‐). Conclusion: Among patients who received HCV NAT+ donor kidneys, no clear association was observed between exposure to HCV NAT+ donor kidneys and viral infections of BKPyV, CMV, or EBV. [ABSTRACT FROM AUTHOR]

Growing worldwide waste management challenges have prompted research efforts for sustainable solutions, especially in green energy technologies. This study highlights robotics' critical role in modern waste management by putting forth a novel strategy incorporating cutting‐edge technologies. The research aims to create an effective waste monitoring system to measure the amounts of methane gas and organic waste at disposal sites. The main component of this method is a 3D‐printed spider robot driven by a servo motor with solid and flexible claws. This robotic system communicates gas level readings to the ThingSpeak platform on the Internet of Things, while it navigates waste disposal sites autonomously. The study also investigates how to develop robotic systems more economically and efficiently by using a portable, low‐power microcontroller, such as the Arduino Nano. The study uses a rigorous testing methodology to assess the performance and viability of the microcontroller and robotic system. The results are expected to emphasise a practical and economic development approach while offering insightful information on developing sustainable waste management technologies. [ABSTRACT FROM AUTHOR]

Power quality is the main problem with the power system network. Poor electricity quality may cause disruptions and financial challenges for consumers. Additionally, it could cause electronic gadgets to overheat, be damaged, or operate inadvertently. Transformers and other components of the power distribution system may also overheat and experience core saturation. This study investigates potential problems with the quality of the electricity in a photovoltaic linked power system. This paper suggests a new optimization method for day-ahead trading and control in DC microgrid power management (MG). The goal of the multiobjective optimization dispatch (MOOD) problem is to lower overall operational costs as well as the costs associated with power loss in efficient conservation systems and exhaust emission quantities such as nitrogen oxides, sulphur dioxide, and carbon dioxide. Using the weighted sum approach, the multiobjective optimization problem is reduced to a single optimization problem. The analytical hierarchy process (AHP) method is then used to calculate the weight coefficients while accounting for each objective function's preferences. Power balancing, high levels of renewable energy penetration, the most effective scheduling of battery charging and discharging, control of load curtailment, and the technical limitations of the system are all taken into account when evaluating the system's performance in both grid-connected and standalone operation modes. The ant lion optimizer (ALO) technique is taken into account to tackle MOOD, comparing the effectiveness of the proposed method to other well-known heuristic optimization techniques. The simulation's results demonstrate how effectively the proposed strategy can address the coordinated control and optimization dispatch difficulties. They also found that operating the MG system economically in grid-connected mode can save overall costs by roughly 4.70% compared to doing it in independent mode. [ABSTRACT FROM AUTHOR]

In a solar power plant, a solid phase transformer and an optimization coordinated controller are utilized to improve transient responsiveness. Transient stability issues in a contemporary electrical power system represent one of the difficult tasks for an electrical engineer due to the rise in uncertain renewable energy sources (RESs) as a result of the need for green energy. The potential for terminal voltage to be adversely impacted by this greater RES raises the possibility of electrical device damage. It is possible to use a solid state transformer (SST) or smart transformer to address a transient response issue. These devices are frequently employed to interact between RES and a power grid. SST features a variety of regulated converters to maintain the necessary voltage levels. This method can therefore simultaneously lessen power fluctuations and transient responsiveness. In order to improve the quality of RES power injections and the electrical system's transient stability, this work provides a controller design for a solar photovoltaic (SPV) system that is connected to the grid by SST. The optimization of a controller model is proposed by modifying a PI controller taken from a commercial one. With the use of IEEE 39 standard buses, the proposed controller is tested. When evaluating the effectiveness of a suggested controller, it is important to take into account a variety of solar radiation patterns as well as a time delay uncertainty that can range from 425 ms to 525 ms. According to simulation results, the proposed controller can be employed to lessen power fluctuation brought on by unpredictable RES. Additionally, the proposed coordinated regulation of SPV and SST can prevent catastrophic damage in the event of substantial disturbances like a circuit breaker collapsing to expand a power line due to a fault by inhibiting significant voltage cycles within an electronic appliance's rated voltage limit. The results indicate that a transitory stability issue in a modern power system caused by an unforeseen increase in RES may be addressed utilizing the suggested controllers as alternatives. [ABSTRACT FROM AUTHOR]

Summary: Li‐ion cells suffer from significant safety and performance problems due to overheating and thermal runaway. Effective thermal management can lead to increased energy conversion efficiency and energy storage density. Critical needs towards these goals include the capability to predict thermal behavior in extreme conditions and determine thermal management requirements to prevent thermal runaway. This paper presents an experimentally validated theoretical model to predict the temperature distribution in a cell in response to nonlinear heat generation rate that is known to occur during thermal runaway. This problem is solved by linearization of the nonlinear term over successive time intervals. Experimental measurements carried out on a thermal test cell in conditions similar to thermal runaway show good agreement with the theoretical model. Experimental measurements and model predictions indicate strong dependence of the fate of the cell on its reaction kinetics, thermal properties, and ambient conditions. Specifically, a sudden change in thermal runaway behavior is predicted once the ambient temperature crosses a certain threshold, consistent with past experimental observations. The impact of increasing cell thermal conductivity on improved thermal runaway performance is quantified. Results presented here provide a fundamental understanding of thermal runaway, and may lead to improved performance and safety of Li‐ion–based energy conversion and storage systems. Develops an analytical thermal runaway model to predict Li‐ion cell temperature under abuse conditions.Presents experimental validation for a wide variety of parameters.Experimentally demonstrates enhanced safety with increase in thermal conductivity.Analyzes effect of different heat transfer and reaction kinetics parameters on cell safety. [ABSTRACT FROM AUTHOR]

Purpose. There are limited resources for long-term specialist follow-up after bariatric surgery. In selected centres, patients can access a postoperative support group, but there is no clear evidence to guide their delivery. Materials and Methods. A retrospective study of bariatric surgery patients (n = 152) who had been discharged from specialist follow-up (mean time since surgery 5.5 years), covering weight history, physical and psychosocial comorbidities, and the need for a postoperative bariatric support group. Results. Fifty-eight percent wanted a postbariatric surgery patient support group. This was not associated with operation type or the amount of weight lost or regained. However, those who wanted a support group were significantly more likely to be struggling to keep the weight off, to be unhappy with the way they look, or to be experiencing difficulties returning to work. Conclusions. These data point to an unmet patient requirement for a postoperative support group that is independent of weight loss success. More research is required to ascertain how such a group should be delivered, but our data would suggest that supporting patients with weight loss maintenance, body image, and return to work is an important part of postoperative care, and these needs extend well beyond the immediate period of specialist follow-up. [ABSTRACT FROM AUTHOR]

The genetic diversity of Human Immunodeficiency Virus type-1(HIV-1) has been shown to affect the performance of Nucleic Acid Testing (NAT) of Human Immunodeficiency Virus type-1. Although, majority NAT assays were designed to detect the conserved regions of HIV-1 mutations at the primer or probe binding regions may lead to false negatives. In this study, we evaluated the feasibility of detecting two genomic targets for enhanced sensitivity. A total of 180 tests using HIV-1 VQA RNA quantitation standard, 240 tests using EQAPOL HIV-1 viral diversity subtype panel, and 30 clinical plasma samples from Cameroon were evaluated. The analysis was based on probit and hit rate. The genomic targets LOD estimated by PROBIT for the gag target was 118 cps/ml (95%CI 64 cps/ml lower bound), Pol or POL/LTR was at 40 cps/ml (95%CI 17, 16 cps/ml), LTR 45 cps/ml (95%CI 20 cps/ml lower bound), and Gag/LTR at 67.8 cps/ml (95%CI 32 cps/ml lower bound). For HIV-1 subtypes the overall reactivity was 55-100% when tested at 100 and 1000 cps/ml and combination of genomic targets detection increased the reactivity to 100%. The plasma samples evaluation showed LTR or pol/LTR combination yielded higher sensitivity for patients with lower viral load (<40 cps/ml). We conclude that detection of two HIV-1 genomic targets improved sensitivity for detection of genetically diverse HIV-1 strains. J. Med. Virol. 88:1092-1097, 2016. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]