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In this research, based on pulse reconstruction method, digital storage oscilloscopes with an 8-bit digital-to-analog convertor was used to successfully perform the neutron-gamma discrimination with NE213 (or its equivalent BC501A) scintillator anode pulses at minimum discrimination bias value of 95 keVee (or keV electron equivalent). Also, a 100 mCi 241 Am–Be source and micro-Curie gamma ray sources ( 137 Cs and 22 Na) were used for the system calibration and discrimination studies. The results confirm the feasibility and simplicity of the proposed method. [ABSTRACT FROM AUTHOR]

Summary Ghrelin is expressed in key cells of the female reproductive organ in several species of fishes. It has a role in the control of fertility. In the present study, the histological effect of ghrelin on 48 female Barbus sharpeyi was tested. Twenty-four hours later, microscopic observations and histometric counting was done. The results indicated that ghrelin can increase the number of mature ovarian follicles and sexual maturation and reduce the average oocyte diameter. [ABSTRACT FROM AUTHOR]

In this paper, a digital neutron–gamma discrimination (DNGD) method with an NE213 scintillator has been proposed in which the anode pulse is divided into two different pulses, one representing the amplitude and the other characterizes the DNGD. Then the two pulses are summed up after travelling through delay and mixer circuits to form an input pulse for sampling in analog–to–digital converter (ADC). The discrimination tests have been performed with an 8–bit digital storage oscilloscope (DSO) as ADC and 241 Am–Be neutron source, whereas the Fourier method has been used to derive the discrimination characteristic. The results confirm the fast performance and efficiency of proposed method. [ABSTRACT FROM AUTHOR]

The effects of diazinon [O,O-diethyl O-(2-isopropyl 1-6-methyl-4 pryimidinyl)] (DZN) on serum estradiol levels in female Chalcalburnus chalcoides fish were studied. Five treatment aquaria were used as follows; control, DZN at 10, 20, 40, and 60 µg L-1 with 20 fish per aquarium. Each treatment was repeated for 24, 48, 72, 96, and 168 h (1 week). After exposure, fish were bled and serum estradiol levels determined by RIA (radioimmunoassay). Data showed a significant reduction in serum estradiol levels at all DZN concentrations used at all time periods. There did not seem to be a time or concentration dependent phenomenon. [ABSTRACT FROM AUTHOR]

A digital data acquisition system together with MATLAB software for data analysis were utilised to measure the pulse specification of the scintillation detector assembly. Besides, the sensitivity of a photomultiplier tube (PMT) window to gamma-rays was studied to discriminate the signals produced as a result of gamma-ray interactions inside the glass window from those originating from the scintillator cell. The result showed that an algorithm based on the time features was capable to evaluate the contributions of these two different signals. [ABSTRACT FROM AUTHOR]

A discrete Fourier transform method (DFTM) for discrimination between the signal of neutrons and gamma rays in organic scintillation detectors is presented. The method is based on the transformation of signals into the frequency domain using the sine and cosine Fourier transforms in combination with the discrete Fourier transform. The method is largely benefited from considerable differences that usually is available between the zero-frequency components of sine and cosine and the norm of the amplitude of the DFT for neutrons and gamma-ray signals. Moreover, working in frequency domain naturally results in considerable suppression of the unwanted effects of various noise sources that is expected to be effective in time domain methods. The proposed method could also be assumed as a generalized nonlinear weighting method that could result in a new class of pulse shape discrimination methods, beyond definition of the DFT. A comparison to the traditional charge integration method (CIM), as well as the frequency gradient analysis method (FGAM) and the wavelet packet transform method (WPTM) has been presented to demonstrate the applicability and efficiency of the method for real-world applications. The method, in general, shows better discrimination Figure of Merits (FoMs) at both the low-light outputs and in average over the studied energy domain. A noise analysis has been performed for all of the abovementioned methods. It reveals that the frequency domain methods (FGAM and DFTM) are less sensitive to the noise effects. [ABSTRACT FROM AUTHOR]