138 research outputs found

    Evaluation and comparison of bivariate and multivariate statistical methods for landslide susceptibility mapping (case study: Zab Basin)

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    Landslides are among the great destructive factors which cause lots of fatalities and financial losses all over the world every year. Studying of the factors affecting occurrence of landslides in a region and zoning the resulting damages will certainly play a crucial role in mitigating such phenomena. In this research, through geological maps and field studies, we primarily prepared a map for landslide distributions in Zab basin-an area of 520 km 2 in the southwest mountainsides of West Azerbaijan Province. By applying other source of information such as the existing thematic maps, we studied and defined the factors (slope, slope aspect, distance to road, distance to drainage network, distance to fault, land use and land cover, geological factors, horizontal gravity acceleration of earthquakes, and climatic condition of the studied area) that affect occurrence of the landslides. To get better precision and higher speed and facility in our analysis, all descriptive and spatial information were entered into geographic information system (GIS) system and Ilwis software. We also used Satellite images (Landsat ETM + and SPOT 5), producing land cover and landslide-inventory maps, respectively. After preparation of the influential parameters on landslides, we drew the zoning maps of slide hazard via four different statistical methods and then evaluated and compared them. By analyzing the obtained index and by comparing landslide distribution map and zoning map of landslide susceptibility prepared by each of the methods in GIS environment, we found that bivariate method of information value analysis, bivariate method of density-area, multivariate method with linear regression analysis, and multivariate method of discriminate analysis take priority, respectively. Finally, as this research shows, despite their simplicity, bivariate statistical methods have more acceptable precision than multivariate methods, and consequently, they are more compatible with landslide susceptibility of the region. From the results, lithology, slope, annual rainfall, land cover, slope aspect, distance to waterway, distance to road, horizontal gravity acceleration, and distance to fault are very influential to landslides in the region

    Evaluation of the chlorpromazine effect on experimental autoimmune encephalomyelitis in male rats

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    زمینه و هدف: در تحقیقات اخیر به افزایش سطح دوپامین در مغز موش های مبتلا به آنسفالومیلیت خود ایمن تجربی (EAE) اشاره شده است. همچنین مشخص شده است که دوپامین می تواند عملکرد سلول های ایمنی را تنظیم کند. در این مطالعه اثرات درمانی کلرپرومازین به عنوان یک آنتاگونیست دوپامین بر روند EAE (مدل حیوانی بیماری ام اس) بررسی شد، همچنین پاسخ های لنفوسیت های T کمکی مورد ارزیابی قرار گرفت. روش بررسی: در این مطالعه تجربی، آنسفالومیلیت خود ایمن تجربی توسط نخاع هموژنیزه شده خوکچه هندی و ادجوانت کامل فروند در موش های صحرایی نر نژاد ویستار القاء شد. حیوانات در دو گروه 7 سری قرار گرفتند. درمان با کلرپرومازین (10 میلی گرم بر کیلوگرم- روزانه و به صورت داخل صفاقی) از زمان بروز علائم ناتوانی در گروه درمانی (روز 12) آغاز گشت. گروه کنترل تنها حلال دارو (آب مقطر) را با همان برنامه دریافت نمودند. علائم بالینی تا زمان کشتار موش ها یعنی روز 36 روزانه ثبت گردید. میزان تکثیر به وسیله آزمون MTT و میزان تولید سیتوکین ‌ها به وسیله ELISA در سلول ‌های طحالی سنجیده شد. یافته ها: تجویز کلرپرومازین پس از بروز علائم به طور معنی داری موجب تخفیف شدت علائم بالینی گشت. همچنین کلرپرومازین موجب کاهش معنی دار (01/0P<) تولید سیتوکین پیش التهابی 17-IL همزمان با افزایش سطح سیتوکین ضد التهابی IL-10 (05/0P<) در موش های صحرایی گروه درمان نسبت به گروه شاهد شد. از سوی دیگر، شدت تکثیر لنفوسیتی نیز در موش های صحرایی گروه تیمار نسبت به گروه شاهد کاهش معنی داری (05/0>P) یافت. نتیجه گیری: نتایج این مطالعه نشان داد کلرپرومازین می تواند سیتوکین های التهابی را کاهش داده و بیماری ام اس را کنترل کند

    Regional and spatial impacts of external and internal conflicts on ecological footprint: the case of Middle East and Africa

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    The economic and environmental structures of countries are greatly impacted by domestic and foreign conflicts. To promote sustainable development, it is crucial to understand the spatial impact of these conflicts on the ecological footprint of a region. With a focus on Middle Eastern and African countries, this paper investigates the impact of such conflicts on their environments, taking into consideration the unique spatial features of their ecological footprints. Using a spatial econometric model, the study assesses the contributions of ecological footprint determinants, particularly internal and external conflict indicators, across 46 Middle Eastern and African countries from 2001 to 2019. The results indicate that internal conflict can lead to increased pressure on natural resources and ecological systems in neighboring countries, while energy use and economic growth impose a significant ecological burden both domestically and abroad. While urbanization and resource rents were found to reduce the ecological footprint, trade openness was found to be nonsignificant. Conflicts such as war, foreign pressure, civil war, and civil disorder were found to have a significant negative impact on the environment, suggesting that reducing these conflicts would improve environmental circumstances. The findings highlight the need for conflict resolution measures to achieve a sustainable environment in the Middle Eastern and African regions and have implications for other countries facing similar issues

    THE EXPRESSION IMPORTANCE OF CARBOHYDRATES IN SOCCER PLAYERS

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    The importance of nutrition is considered for improving performances in adolescents soccer players. The purpose of this paper is overview of the significance of the carbohydrate in football. The importance of proper nutrition for athletes and the public is well recognized, so we should be dedicated to further progress for soccer players. Considering the nutritional needs of athletes, researcher and coach can create improvements in their performance.Важность питания рассматривается для улучшения работы подростков-футболистов. Цель этой статьи — обзор значимости углеводов в футболе. Важность правильного питания для спортсменов и общественности хорошо известна, поэтому мы должны быть нацелены на дальнейший прогресс для футболистов. Учитывая потребности спортсменов в питании, исследователь и тренер могут улучшить свои результат

    Model predictive-based secondary frequency control considering heat pump water heaters

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    The extensive development of renewable energies in power systems causes several problems due to intermittent output power generation. To tackle the challenge, demand response contribution to ancillary service is currently well recognized under the smart grid infrastructure. The application of the heat pump water heater (HPWH) as a controllable load in primary frequency control is well presented in the literature; however, the motivation of this paper is to use HPWHs for secondary frequency control. To this end, a model predictive control (MPC) method for a two-area power system incorporating HPWHs to contribute to secondary frequency control is proposed in this paper. A detailed model of HPWH is employed as a controllable load to control the power consumption during water heating. The MPC method predicts the future control signals using a quadratic programming-based optimization. It uses the system model, past inputs and outputs, as well as system control signals to predict the next signals. The effective performance of the proposed method for the two-area power system with HPWH is demonstrated for different scenarios of load changes, intermittent renewable power generation and parameter variations as the sensitivity analysis

    Evaluation of the analgesic efficacy of melatonin in patients undergoing cesarean section under s pinal anesthesia: A prospective randomized double-blind study

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    Melatonin has been suggested as a new natural pain killer in inflammatory pain and during surgical procedures. We designed this randomized double-blind controlled study to evaluate the analgesic efficacy and also optimal preemptive dose of melatonin in patients undergoing cesarean section under spinal anesthesia. One hundred twenty patients scheduled for cesarean section under spinal anesthesia were randomly allocated to one of three groups of 40 each to receive melatonin 3 milligram (mg) (group M3), melatonin 6 mg (group M6) or placebo (group P) sublingually 20 min before the spinal anesthesia. The time to first analgesic request, analgesic requirement in the first 24 h after surgery, hemodynamic variables, anxiety scores nd the incidence of adverse events were recorded. The duration of anesthesia and analgesia didn�t show significant differences between three groups. Total analgesic request during 24 h after surgery was different among the three groups (P = 0.035). The incidence of headache in group M6 was significantly higher than others (P<0.001). However, after adjusting headache between groups of the study, we were unable to show the significant difference in the total analgesic request during 24 h after surgery among the three groups (p = 0.058). Although premedication of patients with 3 mg sublingual melatonin prolonged time to first analgesic request after cesarean delivery compared to placebo group, the difference was not statistically significant. Meanwhile increasing dose of melatonin to 6 mg failed to enhance analgesia and also increase the incidence of headache in patients undergoing cesarean section under spinal anesthesia. © 2016 by School of Pharmacy

    Guest editorial: Application of cloud energy storage systems in power systems

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    Cloud energy storage system (CESS) technology is a novel idea to eliminate the distributed energy storage systems from the consumers into a cloud service centre, where CESS acts as a virtual energy storage capacity instead of the actual devices. The power and energy of several distributed energy storages are combined using a CESS to assure providing storage services for small consumers. A CESS is a shared pool of grid-scale energy storage systems to reduce the cost of energy storage services in the power system which can increase the penetration level of onsite distributed renewable energy sources, reduce the electricity bills of consumers, and provide flexibility to the power grid by reducing the peak loads. The current Special Issue aims to explore technologies, methodologies, and solutions to develop CESSs with an efficient, secure, and stable operation of power systems.Scopu

    O-C Study of 545 Lunar Occultations from 13 Double Stars

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    International audienceIn this article, we have studied the reports of lunar occultations by this project observation's teams (named APTO) in comparison with other observations of the objects. Thirteen binary stars were selected for this study. All the previous observations of these stars were also collected. Finally, an analysis of O-C of all reports were performed

    Computational Fluid Dynamics Simulation of Gas-Solid Hydrodynamics in a Bubbling Fluidized-Bed Reactor: Effects of Air Distributor, Viscous and Drag Models

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    In this work, we employed a computational fluid dynamics (CFD)-based model with a Eulerian multiphase approach to simulate the fluidization hydrodynamics in biomass gasification processes. Air was used as the gasifying/fluidizing agent and entered the gasifier at the bottom which subsequently fluidized the solid particles inside the reactor column. The momentum exchange related to the gas-phase was simulated by considering various viscous models (i.e., laminar and turbulence models of the re-normalisation group (RNG), k-ε and k-ω). The pressure drop gradient obtained by employing each viscous model was plotted for different superficial velocities and compared with the experimental data for validation. The turbulent model of RNG k-Ɛ was found to best represent the actual process. We also studied the effect of air distributor plates with different pore diameters (2, 3 and 5 mm) on the momentum of the fluidizing fluid. The plate with 3-mm pores showed larger turbulent viscosities above the surface. The effects of drag models (Syamlal–O’Brien, Gidaspow and energy minimum multi-scale method (EMMS) on the bed’s pressure drop as well as on the volume fractions of the solid particles were investigated. The Syamlal–O’Brien model was found to forecast bed pressure drops most consistently, with the pressure drops recorded throughout the experimental process. The formation of bubbles and their motion along the gasifier height in the presence of the turbulent flow was seen to follow a different pattern from with the laminar flow.Ministry of Higher Education (MOHE) Malaysia; Engineering and Physical Sciences Research Counci
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