109 research outputs found

    A Novel Hybrid Algorithm for Optimized Solutions in Ocean Renewable Energy Industry: Enhancing Power Take-Off Parameters and Site Selection Procedure of Wave Energy Converters

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    Ocean renewable energy, particularly wave energy, has emerged as a pivotal component for diversifying the global energy portfolio, reducing dependence on fossil fuels, and mitigating climate change impacts. This study delves into the optimization of power take-off (PTO) parameters and the site selection process for an offshore oscillating surge wave energy converter (OSWEC). However, the intrinsic dynamics of these interactions, coupled with the multi-modal nature of the optimization landscape, make this a daunting challenge. Addressing this, we introduce the novel Hill Climb - Explorative Gray Wolf Optimizer (HC-EGWO). This new methodology blends a local search method with a global optimizer, incorporating dynamic control over exploration and exploitation rates. This balance paves the way for an enhanced exploration of the solution space, ensuring the identification of superior-quality solutions. Further anchoring our approach, a feasibility landscape analysis based on linear water wave theory assumptions and the flap's maximum angular motion is conducted. This ensures the optimized OSWEC consistently operates within safety and efficiency parameters. Our findings hold significant promise for the development of more streamlined OSWEC power take-off systems. They provide insights for selecting the prime offshore site, optimizing power output, and bolstering the overall adoption of ocean renewable energy sources. Impressively, by employing the HC-EGWO method, we achieved an upswing of up to 3.31% in power output compared to other methods. This substantial increment underscores the efficacy of our proposed optimization approach. Conclusively, the outcomes offer invaluable knowledge for deploying OSWECs in the South Caspian Sea, where unique environmental conditions intersect with considerable energy potential.Comment: 35 pages, 22 Figures, 7 Table

    Studying the factors associated with Premenstrual syndrome prevention among pre-university students in Tehran

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    Context: Premenstrual syndrome is one of the common menstrual disorders in adolescents. Considering the destructive effects of this syndrome on adolescents’ activity and performance and the importance of epidemiological studies in designing preventive interventions, Aims: this study aimed to determine some of the factors associated with the prevention of premenstrual syndrome among adolescents. Settings and Design: In a cross-sectional study, 255 female high school students in Tehran were selected using multistage random sampling method. Methods and Material: The data were collected using a demographic and background questionnaire and a valid and reliable questionnaire to assess preventive behaviors of premenstrual syndrome. Statistical analysis used: The collected data were analyzed using SPSS software version 16 and descriptive statistics and logistic regression.      Results: The mean (SD) score of adoption of preventive behaviors of premenstrual syndrome was 19.25 (0.63) out of 50, and it was low. Also, weekly physical activity, mother education level, and family income were the factors affecting the adoption of preventive behaviors of premenstrual syndrome (P<0.05).­­­ Conclusion: Due to the low adoption of preventive behaviors among students with lower income families, students with less physical activity and students with mothers with lower levels of education, it is suggested that more attention be paid to the above students in designing educational programs to promote the prevention of premenstrual syndrome. Keywords: Premenstrual Syndrome, Preventive behavior, Female Students­­ &nbsp

    The Combined Effects of a Methacrylate Powder Dressing (Altrazeal Powder) and Photobiomodulation Therapy on the Healing of a Severe Diabetic Foot Ulcer in a Diabetic Patient: A Case Report

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    Weakened wound healing is a popular, severe complication of patients with diabetes that poses a risk for foot infection and amputation. In recent years, researchers have been searching to find new treatments for treating diabetic foot ulcer.  In this case report for the first time, we applied photobiomodulation therapy and Altrazeal powder together to treat and expedite tissue repair in a severe case of diabetic foot ulcer in a 47-year-old woman who suffered from type 1 diabetes.   We observed along with progress of combination therapy, the ulcer area was significantly reduced, and the wound healed within 16 weeks. Also, dermatitis and purulent secretion were treated, and pain was reduced. This reported case study, indicated the beneficial impact of the combination of photobiomodulation therapy and Altrazeal powder for the healing of a severe of diabetic foot ulcer in a patient with type one diabetes. Combined application of photobiomodulation therapy plus Altrazeal powder demonstrated an additive effect. Further clinical trials in clinical setting in is suggested to validate the results further. In addition, more studies in preclinical models are suggested to find mechanism of action of the combination therapy

    Simultaneous Cesarean Section and Radical Nephrectomy With Tumor Thrombectomy During Pregnancy

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    Renal cell carcinoma (RCC) is uncommon during pregnancy. Accurate and timely diagnosis and careful preoperative planning are essential to optimize the patient outcomes. A 27-year-old pregnant woman presented with a large mass in left kidney and inferior vena cava (IVC) tumor thrombus, diagnosed at 33 weeks gestation. She was evaluated with an initial impression of pyelonephritis at other institutions and referred to our center after a delay of more than 3 weeks. RCC with IVC tumor thrombus has the potential to increase the likelihood of thromboembolic events including pulmonary embolism during pregnancy. Furthermore, simultaneous radical nephrectomy with IVC thrombectomy and Cesarean section (CS) is challenging and might be associated with significant intraoperative blood loss. After consultation with an obstetrician and cardiac surgery team, our patient underwent CS and simultaneous left radical nephrectomy with IVC thrombectomy at 34 weeks gestation. The postoperative course was uneventful and histologic analysis revealed pT3bN0M0 papillary RCC

    Future and potential spending on health 2015-40 : development assistance for health, and government, prepaid private, and out-of-pocket health spending in 184 countries

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    Background The amount of resources, particularly prepaid resources, available for health can affect access to health care and health outcomes. Although health spending tends to increase with economic development, tremendous variation exists among health financing systems. Estimates of future spending can be beneficial for policy makers and planners, and can identify financing gaps. In this study, we estimate future gross domestic product (GDP), all-sector government spending, and health spending disaggregated by source, and we compare expected future spending to potential future spending. Methods We extracted GDP, government spending in 184 countries from 1980-2015, and health spend data from 1995-2014. We used a series of ensemble models to estimate future GDP, all-sector government spending, development assistance for health, and government, out-of-pocket, and prepaid private health spending through 2040. We used frontier analyses to identify patterns exhibited by the countries that dedicate the most funding to health, and used these frontiers to estimate potential health spending for each low-income or middle-income country. All estimates are inflation and purchasing power adjusted. Findings We estimated that global spending on health will increase from US9.21trillionin2014to9.21 trillion in 2014 to 24.24 trillion (uncertainty interval [UI] 20.47-29.72) in 2040. We expect per capita health spending to increase fastest in upper-middle-income countries, at 5.3% (UI 4.1-6.8) per year. This growth is driven by continued growth in GDP, government spending, and government health spending. Lower-middle income countries are expected to grow at 4.2% (3.8-4.9). High-income countries are expected to grow at 2.1% (UI 1.8-2.4) and low-income countries are expected to grow at 1.8% (1.0-2.8). Despite this growth, health spending per capita in low-income countries is expected to remain low, at 154(UI133181)percapitain2030and154 (UI 133-181) per capita in 2030 and 195 (157-258) per capita in 2040. Increases in national health spending to reach the level of the countries who spend the most on health, relative to their level of economic development, would mean $321 (157-258) per capita was available for health in 2040 in low-income countries. Interpretation Health spending is associated with economic development but past trends and relationships suggest that spending will remain variable, and low in some low-resource settings. Policy change could lead to increased health spending, although for the poorest countries external support might remain essential.Peer reviewe

    Diagnostic Performance of Ultrasonography for Identification of Small Bowel Obstruction: A Systematic Review and Meta-analysis

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    Introduction: Small bowel obstruction (SBO) is known as a common cause of acute abdominal complaints in the emergency department (ED). The modality of choice for the diagnosis of SBO has not yet been established. This systematic review and meta-analysis aimed to investigate the accuracy of ultrasonography for the diagnosis of SBO. Methods: Systematic search was performed on five electronic databases including Medline, Scopus, Web of Sciences, Embase, and Cochrane Library, and the retrieval period was from the inception of each database to November 2023. The quality of the included studies were investigated using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). The pooled values of diagnostic characteristics for ultrasonography were estimated using meta-Disc and Stata statistical software. Results: Twenty-one studies with a total of 1977 patients were included in the meta-analysis. The pooled estimate for sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the summary ROC curve of ultrasonography for diagnosing SBO were 0.93 (95% CI: 0.91–0.95), 0.8 (95% CI: 0.77–0.83), 5.69 (95% CI: 3.64–8.89), 0.1 (95% CI: 0.07–0.16), 83.51 (95% CI: 18.12–182.91) and 0.96, respectively. Conclusion: The findings of this meta-analysis showed that the utilization of ultrasonography holds promise as a diagnostic imaging for SBO with high accuracy. However, additional worldwide studies are essential to get more evidence on the value of ultrasonography for the diagnosis of SBO

    Future and potential spending on health 2015-40: Development assistance for health, and government, prepaid private, and out-of-pocket health spending in 184 countries

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    Background: The amount of resources, particularly prepaid resources, available for health can affect access to health care and health outcomes. Although health spending tends to increase with economic development, tremendous variation exists among health financing systems. Estimates of future spending can be beneficial for policy makers and planners, and can identify financing gaps. In this study, we estimate future gross domestic product (GDP), all-sector government spending, and health spending disaggregated by source, and we compare expected future spending to potential future spending. Methods: We extracted GDP, government spending in 184 countries from 1980-2015, and health spend data from 1995-2014. We used a series of ensemble models to estimate future GDP, all-sector government spending, development assistance for health, and government, out-of-pocket, and prepaid private health spending through 2040. We used frontier analyses to identify patterns exhibited by the countries that dedicate the most funding to health, and used these frontiers to estimate potential health spending for each low-income or middle-income country. All estimates are inflation and purchasing power adjusted. Findings: We estimated that global spending on health will increase from US9.21trillionin2014to9.21 trillion in 2014 to 24.24 trillion (uncertainty interval [UI] 20.47-29.72) in 2040. We expect per capita health spending to increase fastest in upper-middle-income countries, at 5.3% (UI 4.1-6.8) per year. This growth is driven by continued growth in GDP, government spending, and government health spending. Lower-middle income countries are expected to grow at 4.2% (3.8-4.9). High-income countries are expected to grow at 2.1% (UI 1.8-2.4) and low-income countries are expected to grow at 1.8% (1.0-2.8). Despite this growth, health spending per capita in low-income countries is expected to remain low, at 154(UI133181)percapitain2030and154 (UI 133-181) per capita in 2030 and 195 (157-258) per capita in 2040. Increases in national health spending to reach the level of the countries who spend the most on health, relative to their level of economic development, would mean $321 (157-258) per capita was available for health in 2040 in low-income countries. Interpretation: Health spending is associated with economic development but past trends and relationships suggest that spending will remain variable, and low in some low-resource settings. Policy change could lead to increased health spending, although for the poorest countries external support might remain essential
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