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  Öğe Türü:Öğe,

  The effect of vitamin E treatment during preovulatory period on reproductive performance of goats following estrous synchronization using intravaginal sponges

  (2009)

  Sönmez, M

  ;

  Bozkurt, T

  ;

  Türk, G

  ;

  Gür, S

  ;

  Kızıl, M

  Daha fazla

  The objectives of this study were to investigate whether the use of intravaginal sponge for estrous synchronization of goats causes oxidative stress, and to examine the effect of administering vitamin E during preovulatory period on reproductive performance of estrous synchronized goats. Estrus was synchronized in 36 nonlactating adult does using intravaginal sponges containing 30mg of fluorogestane acetate (FGA) for 14 days. All females received 500 IU of eCG at the sponge withdrawal. The goats were allocated at random to two groups balanced for breed, age and body weight. Treatment group (n = 18) received 200mg of vitamin E i.m. at the time of sponge removal and again at the time of second artificial insemination. The other 18 goats (control) were administered 1 ml of physiological saline instead of vitamin E on each of these two occasions. All does in estrus was intracervically inseminated at 12 and 24 h after the onset of estrus. Blood samples were collected every 72 h during the experimental period for evaluation of malondialdehyde (MDA) and vitamin E concentrations. Serum MDA level increased and vitamin E concentration decreased during the period of vaginal sponge application. Following the sponge removal, MDA level declined rapidly to below basal level in the treatment group but remained high in the control group. Conversely, vitamin E concentration increased in the treatment group after the sponge withdrawal and remained at a low level in the control group. No statistically significant differences (P > 0.05) were observed between groups in terms of estrous response, conception rate, gestation length or kidding rate.However, thenumber of multiple births (70.0% versus 50.0%) and prolificacy rate (2.40±0.37 versus 1.63±0.26 kids per kidding) were significantly higher (P < 0.05) for the treatment group than those of the control group. The results indicate that the use of intravaginal sponges for estrous synchronization of goats causes an increase in level of oxidative stress. However, the vitamin E treatment during preovulatory period can prevent the overproduction of reactive oxygen species (ROS), and it may improve the multiple birth rates and the number of kids born in estrous synchronized goats.

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  Öğe Türü:Öğe,

  A least squares support vector machine model for prediction of the next day solar insolation for effective use of PV systems

  (2014-01-18)

  Bektaş Ekici, Betül

  ;

  TR18334

  Daha fazla

  Accurate prediction of daily solar insolation has been one of the most important issues of solar engineering. The amount of solar insolation on a given location is a vital data for photovoltaic plants. Systems efficiency is easily affected by the changes in solar radiation so, this study is aimed to develop a Least Squares Support Vector Machine (LS-SVM) based intelligent model to predict the next day’s solar insolation for taking measures. Daily temperature and insolation data measured by Turkish State Meteorological Service for three years (2000–2002) were used as training data and the values of 2003 used as testing data. Numbers of the days from 1st January, daily mean temperature, daily maximum temperature, sunshine duration and the solar insolation of the day before parameters have been used as inputs to predict the daily solar insolation. The simulations were carried out with SVM Toolbox of MATLAB software. As a conclusion the results show that LS-SVM is a good method in estimating the amount of solar insolation of a given location with 99.294% accuracy.

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  A study on dynamic modulus of self-consolidating rubberized concrete

  (2015-02-21)

  Emiroğlu, Mehmet

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  Yıldız, Servet

  ;

  Keleştemur, M. Halidun

  ;

  TR186257

  ;

  TR12078

  Daha fazla

  In this study, dynamic modulus of elasticity of self-consolidating rubberized concrete is evaluated by using results of ultrasonic pulse velocity and resonance frequency tests. Additionally, correlation between dynamic modulus of elasticity and compressive strength results is compared. For evaluating the dynamic modulus of elasticity of self-consolidating rubberized concrete, prismatic specimens having 100 x 100 x 500 mm dimensions are prepared. Dynamic modulus of elasticity values obtained by non-destructive measurements techniques are well agreed with those given in the literature.

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  Öğe Türü:Öğe,

  APRICOT PIP SHELLS USED AS AGGREGATE REPLACEMENT

  (2011-03-03)

  Yıldız, Servet

  ;

  Emiroğlu, Mehmet

  ;

  Atalar, Onur

  Daha fazla

  To improve the undesired characteristics of concrete, for example high CO2 emission and loss of strata from quarrying of raw materials, environmentally hazardous solid waste could be utilized as cement, sand and/or aggregate replacement. Apricot Pip Shells (APSs) are an environmental problem mainly in the region where apricots are cultivated. The shells are burnt as a fuel by local people in this region. An alternative use for this waste material would be for aggregate replacement in concrete as reported in this paper. In this study, limestone aggregate were substituted by different percentage of APS in the prepared concrete mixes. Unit weight, compressive and tensile strength tests were conducted on the specimens. A decrease was observed in the strength development of the concrete containing APS. This may have resulted from the weak adherence between APSs and cement paste in the interfacial transition zone. However, the unit weight of the concrete decreased for higher APS content in the mix

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  Performance of a swimming pool heating system by utilizing waste energy rejected from an ice rink with an energy storage tank

  (2016-08-01)

  Kuyumcu, Muhammed Enes

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  Tutumlu, Hakan

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  Yumrutaş, Recep

  ;

  TR24245

  ;

  TR59286

  Daha fazla

  This study deals with determining the long period performance of a swimming pool heating system by utilizing waste heat energy that is rejected from a chiller unit of ice rink and subsequently stored in an underground thermal energy storage (TES) tank. The system consists of an ice rink, a swimming pool, a spherical underground TES tank, a chiller and a heat pump. The ice rink and the swimming pool are both enclosed and located in Gaziantep, Turkey. An analytical model was developed to obtain the performance of the system using Duhamel’s superposition and similarity transformation techniques. A computational model written in MATLAB program based on the transient heat transfer is used to obtain the annual variation of the ice rink and the swimming pool energy requirements, the water temperature in the TES tank, COP, and optimum ice rink size depending on the different ground, TES tank, chiller, and heat pump characteristics. The results obtained from the analysis indicate that 6–7 years’ operational time span is necessary to obtain the annual periodic operation condition. In addition, an ice rink with a size of 475 m2 gives the optimum performance of the system with a semi-Olympic size swimming pool (625 m2).

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