Elazg, Turkey
Elazg, Turkey

Fırat University is a state university based in Elazığ, Turkey. The university was founded in 1975 and named after the Turkish name of the Euphrates River which originates near Elazığ. Being one of the major academic institutions in the Eastern Turkey, the university has twelve schools, four institutes, one state conservatory, three vocational high schools and twenty one research centers with a strong emphasis on scientific and technological advancement and research. Wikipedia.


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Aydin S.,Firat University
Peptides | Year: 2014

Homeostasis of energy is regulated by genetic factors, food intake, and energy expenditure. When energy input is greater than expenditure, the balance is positive, which can lead to weight gain and obesity. When the balance is negative, weight is lost. Regulation of this homeostasis is multi-factorial, involving many orexigenic (appetite-stimulating) and anorexigenic (appetite-suppressing) peptide hormones. Peripheral tissues are now known to be involved in weight regulation and research on its endocrine characteristics proceeds apace. Preptin with 34 amino acids (MW 3948 Da), adropin with 43 amino acids and a molecular weight of (4999 Da), and irisin with 112 amino acids (12587 Da), are three newly discovered peptides critical for regulating energy metabolism. Preptin is synthesized primarily in pancreatic beta cells, and adropin mainly in the liver and brain, and many peripheral tissues. Irisin, however, is synthesized principally in the heart muscle, along with peripheral tissues, including salivary glands, kidney and liver. The prime functions of preptin and adropin include regulating carbohydrate, lipid and protein metabolisms by moderating glucose-mediated insulin release. Irisin is an anti-obesitic and anti-diabetic hormone regulating adipose tissue metabolism and glucose homeostasis by converting white to brown adipose tissue. This review offers a historical account of these discovery and function of these peptides, including their structure, and physiological and biochemical properties. Their roles in energy regulation will be discussed. Their measurement in biological fluids will be considered, which will lead to further discussion of their possible clinical value. © 2014 Elsevier Inc.


The present study was carried out to investigate the potential ameliorative effects of lycopene against chlorpyrifos (CPF) toxicity in carp. The fish were divided into 7 different experimental groups and received the following treatments: Group 1, control; Group 2, orally administered corn oil; Group 3, oral lycopene (10mgkg-1 body weight); Group 4, exposure to 0.040mgL-1 CPF; Group 5, exposure to 0.040mgL-1 CPF plus oral administration of 10mgkg-1 lycopene; Group 6, exposure to 0.080mgL-1 CPF; and Group 7, exposure to 0.040mgL-1 CPF plus oral administration of 10mgkg-1 lycopene. Treatment was continued for 14d and samples of the blood and tissue (liver, kidney, and gill) were collected at the end of the experiment and analysed for their oxidant-antioxidant status, including the malondialdehyde (MDA) levels, and the superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activity. The samples were also measured for changes in the haematological parameters, such as the red blood cell (RBC) and white blood cell (WBC) counts, the haemoglobin concentration (Hb), the haematocrit (Ht) level, and the erythrocyte indices: the mean corpuscular volume (MCV), the mean corpuscular haemoglobin (MCH) and the mean corpuscular haemoglobin concentration (MCHC). The findings of this study demonstrated that CPF had a negative effect on the haematological parameters and the antioxidant enzyme activities of the fish; this toxic effect was neutralised by the administration of lycopene. The present results suggest that lycopene (10mgkg-1) can be effective in the protection of CPF-induced toxicity in fish. © 2012 Elsevier Ltd.


A comprehensive economic analysis has been performed to inter-relate the optimum thickness of insulation materials for various wall orientations. The yearly cooling and heating transmission loads of building walls were determined by use of implicit finite-difference method with regarding steady periodic conditions under the climatic conditions of Elazi{dotless}ĝ, Turkey. The economic model including the cost of insulation material and the present value of energy consumption cost over lifetime of 10. years of the building was used to find out the optimum insulation thickness, energy savings and payback periods for all wall orientations. Considered insulation materials in the analysis were extruded polystyrene and polyurethane. As a result, the optimum insulation thickness of extruded polystyrene was found to be 5.5. cm for south oriented wall and 6. cm for north, east and west oriented walls. Additionally, the lowest value of the optimum insulation thickness and energy savings were obtained for the south oriented wall while payback period was almost same for all orientations. © 2011 Elsevier Ltd.


Ilkilic C.,Firat University
Renewable and Sustainable Energy Reviews | Year: 2012

In this study, the potential of wind energy and assessment of wind energy systems in Turkey were studied. The main purpose of this study is to investigate the wind energy potential and future wind conversion systems project in Turkey. The wind energy potential of various regions was investigated; and the exploitation of the wind energy in Turkey was discussed. Various regions were analyzed taking into account the wind data measured as hourly time series in the windy locations. The wind data used in this study were taken from Electrical Power Resources Survey and Development Administration (EIEI) for the year 2010. This paper reviews the assessment of wind energy in Turkey as of the end of May 2010 including wind energy applications. Turkey's total theoretically available potential for wind power is around 131,756.40 MW and sea wind power 17,393.20 MW annually, according to TUREB (TWEA). When Turkey has 1.5 MW nominal installed wind energy capacity in 1998, then this capacity has increased to 1522.20 MW in 2010. Wind power plant with a total capacity of 1522.20 MW will be commissioned 2166.65 MW in December 2011. © 2011 Elsevier Ltd. All rights reserved.


Alatas B.,Firat University
Expert Systems with Applications | Year: 2010

Artificial bee colony (ABC) is the one of the newest nature inspired heuristics for optimization problem. Like the chaos in real bee colony behavior, this paper proposes new ABC algorithms that use chaotic maps for parameter adaptation in order to improve the convergence characteristics and to prevent the ABC to get stuck on local solutions. This has been done by using of chaotic number generators each time a random number is needed by the classical ABC algorithm. Seven new chaotic ABC algorithms have been proposed and different chaotic maps have been analyzed in the benchmark functions. It has been detected that coupling emergent results in different areas, like those of ABC and complex dynamics, can improve the quality of results in some optimization problems. It has been also shown that, the proposed methods have somewhat increased the solution quality, that is in some cases they improved the global searching capability by escaping the local solutions. © 2010 Elsevier Ltd. All rights reserved.


The main objective of this study is to determine optimum insulation thickness according to cooling requirements of buildings in a hot climate. The investigation is carried out using an implicit finite difference method under steady periodic conditions for different wall orientations during the summer period in Antalya, Turkey. For this purpose, a computer program developed in Matlab is utilized. Firstly, thermal characteristics such as cooling transmission load, time lag, and decrement factor are calculated. Then, the optimum insulation thicknesses for all wall orientations are determined by using a cost analysis over lifetime of 20 years of the building. It is seen that for cooling season, the lowest value of optimum insulation thickness is obtained for the north-facing wall which has minimum cooling load while the highest thickness is obtained for the east and west walls providing the maximum cooling load. The results show that for cooling season, the most economical orientation is north with an optimum insulation thickness of 3.1 cm. Results obtained are also compared with the degree-days and degree-hours methods. © 2012 Elsevier Ltd. All rights reserved.


The aim of this study is to provide a remedy for the low thermo-physical properties of air which is used as different absorber surface of air heater. This paper presents an experimental investigation on the absorber surface of the collector whose shape and arrangement were made up to provide better heat transfer surfaces. In the study an experimental performance and exergy analysis of five types of air heating solar collectors: corrugated trapeze, reverse corrugated, reverse trapeze, and a base flat-plate collector are presented. The results of the experiments were evaluated at the same time of the days with the same radiation. The efficiencies were determined for the collectors and comparisons were made among them. The present data showed that heat transfer coefficient and pressure drop increase with shape of absorbers surface. © 2012 Elsevier Ltd.


In this study, the effect of insulation location on the heat transfer characteristics of building walls and optimization of insulation thickness are investigated numerically using an implicit finite difference method under steady periodic conditions. The investigation is carried out for a south-facing wall in the climatic conditions of ElazIǧ, Turkey. For this purpose, insulation is placed at outside, inside and middle of the wall. Firstly, thermal characteristics such as cooling and heating transmission loads, time lag and decrement factor are determined for each insulation position. Then, the insulation thickness is optimized by using a cost analysis over a building lifetime of 20 years. Results show that insulation location has a significant effect on the yearly averaged time lag and decrement factor. However, yearly transmission loads and hence, optimum insulation thickness are not affected by insulation location. It is seen the maximum temperature swings and peak load in both summer and winter occur in the case that insulation is placed at middle of wall while wall with outside insulation gives the smallest fluctuation. © 2013 Elsevier B.V. All rights reserved.


The environmental Kuznets curve (EKC) hypothesis assumes that there is an inverted U-shaped relationship between environmental degradation and income per capita. In other words, as a country grows, it is assumed that its environmental quality improves. In this study, we aim to test the EKC hypothesis for 12 Middle East countries during the period 1990-2008 by employing recently developed panel data methods. Our results provide evidence contrary to the EKC hypothesis. We found evidence favorable to the U-shaped EKC for 5 Middle East countries, whereas an inverted U-shaped curve was identified for only 3 Middle East countries. Furthermore, there appear to be no causal links between income and CO2 emissions for the other 4 countries. Regarding the direction of causality, there appears to be a unidirectional causality from economic growth to energy consumption in the short-run; in the long-run, however, the unidirectional causality chain runs from energy consumption and economic growth to CO2 emissions. We also suggest some crucial policy implications depending on these results. © 2013 Elsevier Ltd.


In this study, the optimum thickness of thermal insulation used to reduce heat gain and losses in buildings is investigated under dynamic thermal conditions by using the climatic conditions of Elazig, Turkey. Numerical method based on an implicit finite difference procedure which has been previously validated is used to determine yearly cooling and heating transmission loads, yearly averaged time lag and decrement factor under steady periodic conditions. These loads are used as inputs to an economic model for the determination of the optimum insulation thickness. The optimum insulation thicknesses, energy savings and payback periods are calculated by using life-cycle cost analysis over lifetime of 20 years of the building. Results show that the optimum insulation thicknesses vary between 5.4 and 19.2 cm, energy savings vary between 86.26 and 146.05 $/m 2, and payback periods vary between 3.56 and 8.85 years for different insulation materials. The environmental impacts of thermal insulation are also investigated. It is seen that by applying optimum insulation thickness in uninsulated wall, yearly fuel consumption and emissions are decreased by 68-89.5% depending on insulation materials. © 2012 Elsevier B.V. All rights reserved.

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