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Micro inverters are power electronics devices integrated close to photovoltaic (PV) panels. PVs produced today could make 92% of its rated power. With the passage of time, the reliability and performance of micro inverter needs to be redesigned to operate under harsh temperature conditions. This paper presents the distribution of electrical and thermal stresses that occur in semiconductor devices of micro inverters. H5 micro inverter topology is simulated and analyzed as a benchmark of losses in devices of PVs. The performance of micro inverter is evaluated on the basis of conduction and switching losses in basic and distributed micro inverters using simulation tool PSIM. H5 inverter single switch conduction losses came out to be in the range of 6 W while the switching losses were about 0.12 W. Net conduction losses of the inverter were 24.2 W while the switching losses were 0.483 W. For modified inverter as well as auxiliary, single switch had conduction losses in the range of 1.64 W while the total conduction losses for individual switching segment were 13.22 W which are almost half of H5 losses. Results revealed that it has a significant impact on the micro inverter which is replaced with distributed components in this design and has a remarkable improvement. The conduction losses are reduced to 73% and that of switching losses are reduced to 58.4%; leading to major contribution in designing cost effective and safe applications for micro inverters. [ABSTRACT FROM AUTHOR]

Objectives: Critically ill patients have raised troponins. This study aimed to assess the incidence of myocardial injury in the intensive care unit (ICU) at a tertiary care hospital and assess the management and prognosis. Methods: This retrospective study included adult patients who were admitted to the ICU of Sultan Qaboos University Hospital, Muscat, Oman, between January and December 2019 and had undergone a high-sensitive cardiac troponin (hs-cTn) assay. Patients admitted with a primary diagnosis of myocardial infarction were excluded. Results: A total of 264 patients had their hs-cTn measured during the study period. Of these, 128 (64.3 ± 17.1 years; 58.6% male) had elevated levels, giving an incidence rate of approximately 48.5%. Those with raised troponin were older and had more co-morbidities. These patients were also more critically ill with lower blood pressure, higher heart rates and increased hypotensive episodes. Of these, 47 were treated for acute coronary syndrome, 32 underwent coronary angiography and only three required stenting. Patients with raised troponin had a poor outcome with only 45 (35.2%) surviving to discharge compared to 101 (74.3%) with normal troponin. Patients with raised troponin had shorter hospital stays than those with normal troponin (16 versus 19 days; P = 0.017). Conclusion: A high proportion of critically ill patients showed evidence of myocardial injury without significant coronary artery disease, which is associated with a poor prognosis. Further prospective studies are required to ascertain the best course of treatment for these patients. [ABSTRACT FROM AUTHOR]

In the wake of the increasing environmental challenges and the urgent need for sustainable development, this study focuses on the complex issue of mineral resource management. Given the growing global demand for minerals and the environmental impact of extraction, the research seeks to uncover the solutions that promote green growth while effectively addressing the ecological consequences of resource utilization in China. In the study, six factors, twenty‐four sub‐factors, and five potential solutions have been identified influencing sustainable mineral resource management and green growth. The study utilizes fuzzy Analytical Hierarchy Process (AHP) to assess these factors and sub‐factors. Following, the study utilizes fuzzy Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method to evaluate and rank five potential solutions for sustainable development. The fuzzy AHP results indicate that environmental impact mitigation, robust policy frameworks, and innovation in extraction techniques are the most crucial factors. The fuzzy TOPSIS findings indicate that technological innovation for sustainability ranks highest, followed by policy‐driven green growth, socio‐economic empowerment, enhanced environmental stewardship, and integrated circular economy approaches. These findings emphasize the critical role of advanced technologies and robust policies in promoting sustainability while addressing the socio‐economic and environmental dimensions of mineral resource management. [ABSTRACT FROM AUTHOR]

In third world countries like Pakistan, the production of electricity has been quickly reduced in past years due to rely on the fossil fuel. According to a survey conducted in 2017, the overall electrical energy capacity was 22,797MW, since the electrical grids have gone too old, therefore the efficiency of grids, goes down to nearly 17000MW. Significant addition of fossil fuel, hydro and nuclear is 64.2%, 29% and 5.8% respectively in the total electricity production in Pakistan. In 2018, the demand crossed 20,223MW, compared to peak generation of 15,400 to 15,700MW as by the Ministry of Water and Power. Country faces a deficit of almost 4000MW to 5000MW for the duration of 2019 hot summer term. Focus on one aspect considering Demand Side Management (DSM) cannot oversea the reduction of gap between power demand and customer supply, which eventually leads to the issue of load shedding. Hence, a scheduling scheme is proposed in this paper called RPSMDSM that is based on selection of those appliances that need to be only Turned-On, on priority during peak hours consuming minimum energy. The Home Energy Management (HEM) system is integrated between consumer and utility and bidirectional flow is presented in the scheme. During peak hours of electricity, the RPSMDSM is capable to persuade less power consumption and accomplish productivity in load management. Simulations show that RPSMDSM scheme helps in scheduling the electricity loads from peak price to off-peak price hours. As a result, minimization in electricity cost as well as (Peak-to-Average Ratio) PAR are accomplished with sensible waiting time. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Klippel-Feil syndrome is rare congenital, musculoskeletal condition that is characterized by the fusion of at least two vertebrae of the neck. The incidence of which is 0.71% as reviewed by Brown et. al in 1400 skeletons. In fewer than 50% of cases, the three classical diagnostic findings of Klippel-Feil syndrome includes a low posterior hairline, a triad of short neck and a limited range of neck movements especially of lateral bending are present. CASE REPORT: In this particular case, we found congenital fusion of C6 and C7 vertebrate, levoscoliosis, basilar invagination and fusion of atlantooccipital joint on right side with no evidence of renal disease, congenital heart disease and neurological impairment except low IQ. This case has classical triad short neck, low posterior hairline and limited cervical range of motion. CONCLUSION: A rare and typical case of Klippel-Feil Syndrome is very important to present for better identification and prompt treatment. [ABSTRACT FROM AUTHOR]