X-ray detectors of the CAST experiment

CERN Axion Solar Telescope (CAST) is an experiment probing hypothetical particles: the axions, created in the solar core. Inside the transverse magnetic field of the CAST magnet, axions can be converted into x-rays, and be detected by four x-ray detectors at CAST. The expected x-ray signal in CAST is in 1-10 keV range, intensity depending strongly on the coupling constant of axion-photon conversion gag, which is expected to be low. This requires CAST to have detectors with very low background levels.The CAST Experiment makes use of three Micromesh Gaseous Structure (micromegas) detectors, which are gaseous detectors, derived from ideas of Multiwire Proportional Chambers (MWPC). CAST Micromegas detectors show perfect stability, good spatial and energy resolution. The intense study on Micromegas has enabled CAST to understand the nature of its background level, and improve it by a factor of 10(2) over ten years. New detector design, new readout system, better cosmic veto and addition of x-ray telescope will further improve the background in the next data taking of the experiment.The Charge-Coupled Device (CCD) of CAST is a pn-CCD detector with 200 x 64 pixels. The CAST CCD is coupled to an X-ray telescope, focusing all the parallel x-rays into a 9 mm diameter spot. The CCD will be replaced by the InGrid detector, a special manufactured micromegas detector. It is able to detect single electrons, and the low energy capabilities will open new frontiers on search of axions and other exotic particles. Another option is the Silicon Drift Detector (SDD), which is being tested in 2013, and has an energy threshold as low as 250eV.The CAST experiment is the pioneering helioscope that excludes an important part of axion mass-coupling constant parameter space, and expects to exclude more in the following years. To succeed CAST, a new experiment, the International AXion Observatory (IAXO) is being designed and optimised, comprising the construction of a magnet specially built for axion search as well as new detectors that will enable to improve the actual limits by 1-1.5 orders of magnitude

Investigation of middle school parents’ attitude towards extracurricular sports activities according to some demographic characteristics

The purpose of this study is to investigate middle school parents’ attitude towards extracurricular sports activities according to some demographic characteristics. The data for the study was obtained from parents of a public school in Aydın Province, in Turkey. To measure parents’ attitude, “The Parents’ Attitude Scales Towards Extracurricular Sports Activities” was used. This scale includes three sub-dimensions: personality development, academic perception, and social support. Descriptive statistics, correlation analysis, and non-parametric tests were used to analyze the data. The findings indicated that parents’ attitude towards extracurricular sports activities were seen to be at a very good level in all dimensions. In demographic variables, only income groups and educational degree groups had significant differences at the p<0.01 level for all of the sub-dimensions. Results indicated that parents’ approach to extracurricular sports activities plays an important role on students’ participation in these activities

The effect of leader-member exchange on job performance of academic staff: An empirical evidence from higher education institutions

Recently, the relationship between leader-member exchange and job performance has become more interesting subject among researchers. However, the literature has a paucity of empirical studies conducted in the higher education institutions; therefore, the relationship between these two variables is not clear. Hence, the purpose of this study was to examine the effect of leader-member exchange on the job performance of academic staff in higher educational institutions. The data for the study were collected from the academic staff (n=174) of five faculties of sport sciences in Turkey. The LMX-7 scale developed by Scandura and Graen (1984) was used to determine the quality of the interactions between leaders (i.e., administrators) and members (i.e., academic staff). Sigler and Pearson’s (2000) job performance scale, which is a modified version of Kirkman and Rosen’s (1999) team productivity scale, was used to measure job performance. The findings exposed a statistically significant positive effect of leader-member exchange on job performance (p<0.05)

Structure Preserving Model Order Reduction of Shallow Water Equations

In this paper, we present two different approaches for constructing reduced-order models (ROMs) for the two-dimensional shallow water equation (SWE). The first one is based on the noncanonical Hamiltonian/Poisson form of the SWE. After integration in time by the fully implicit average vector field method, ROMs are constructed with proper orthogonal decomposition/discrete empirical interpolation method (POD/DEIM) that preserves the Hamiltonian structure. In the second approach, the SWE as a partial differential equation with quadratic nonlinearity is integrated in time by the linearly implicit Kahan's method and ROMs are constructed with the tensorial POD that preserves the linear-quadratic structure of the SWE. We show that in both approaches, the invariants of the SWE such as the energy, enstrophy, mass, and circulation are preserved over a long period of time, leading to stable solutions. We conclude by demonstrating the accuracy and the computational efficiency of the reduced solutions by a numerical test problem

Role of stocking density of tilapia (Oreochromis aureus) on fish growth, water quality and tomato (Solanum lycopersicum) plant biomass in the aquaponic system

The present study reports the results of the production of Nile tilapia (Oreochromis aureus) and tomato (Solanum lycopersicum) in the classical aquaponic system (one-loop) with different fish density. The experiment as the first scientific aquaponics study in Turkey was conducted at the Ankara University, Faculty of Agriculture, using in-door, small-scale classical aquaponic systems. Ninety six tilapia juveniles (O. aureus) were stocked at different ratio; 25 kg/m3 (Group I), 35 kg/m3 (Group II) and 50 kg/m3 (Group III) and fed with 45% raw protein feed at the level of 2% body weight for 126 days. Fish density affected the fish growth parameters and the most densiest group showed the best results in terms of fish growth and feed efficiency. Water quality parameters measured fluctated during the experiment even the exceed of the optimal ranges for the fish. However, tilapia tolerated the changes of water quality. Total plant biomass was low with the various limiting factors including insufficient lighting of in-door aquaponics system and low level of water potassium. The results of this study clearly illustrate the fish stocking rate has an impact on total biomass in the aquaponics and in one-loop aquaponics the water quality fluctation is the main challenging factor

Reduced order modelling of nonlinear cross-diffusion systems

In this work, we present a reduced-order model for a nonlinear cross-diffusion problem from population dynamics, for the Shigesada-Kawasaki-Teramoto (SKT) equation with Lotka-Volterra kinetics. The finite-difference discretization of the SKT equation in space results in a system of linear--quadratic ordinary differential equations (ODEs). The reduced order model (ROM) has the same linear-quadratic structure as the full order model (FOM). Using the linear-quadratic structure of the ROM, the reduced-order solutions are computed independent of the full solutions with the proper orthogonal decomposition (POD). The computation of the reduced solutions is further accelerated by applying tensorial POD. The formation of the patterns of the SKT equation consists of a fast transient phase and a long steady-state phase. Reduced order solutions are computed by separating the time, into two-time intervals. In numerical experiments, we show for one-and two-dimensional SKT equations with pattern formation, the reduced-order solutions obtained in the time-windowed form, i.e., principal decomposition framework (P-POD), are more accurate than the global POD solutions (G-POD) obtained in the whole time interval. Furthermore, we show the decrease of the entropy numerically by the reduced solutions, which is important for the global existence of nonlinear cross-diffusion equations such as the SKT equation.Comment: To appear in Applied Mathematics and Computatio

Beden eğitimi ve spor eğitimi veren yükseköğretim kurumlarının istihdam durumlarına yönelik öğrenci görüşleri

90 students of Balıkesir University  Physical Education and Sports Institute participated in this study which is made in the purpose of investigating the ideas of students through the condition of employment of the instutions that gives the physical and sports education course.A 5 pointed Likert type scale applied to the students. The arithmethic avareges and standart deviation of the datas that are gained, the meaninfulness through the changings One Way ANOMA is used, in order to determine the differences between the groups of TUKEY HSD is used..After the anylse it is observed that the expressions “opening too many schools and varities of these schools affect the future of these schools badly” and “receiving too many students in this schools accelerate the process of educating students” are choosed very much. And the students compelety agreed with the expressions of “there is an lopsidedness between receing students and employement” and “employement is restraint in the public and private sector. Beden eğitimi ve spor eğitimi veren yükseköğretim kurumlarının istihdam durumlarına yönelik öğrenci görüşlerinin incelenmesi amacıyla yapılan bu çalışmaya, Balıkesir Üniversitesi Beden Eğitimi ve Spor Yüksekokulu’ndan 90 öğrenci katılmıştır. Öğrencilere istihdam durumu ile ilgili 5 maddelik Likert tarzı bir ölçek uygulanmıştır. Elde edilen verilerin aritmetik ortalamaları ve standart sapmaları hesaplanmış, değişkenler arasındaki anlamlılığı tespit etmek için One-Way ANOVA, gruplar arasındaki farklılığı belirlemek için de Tukey HSD uygulanmıştır. Analiz sonucunda öğrencilerin ölçekte yer alan ifadelerden ‘çok sayıda okul açılması ve çeşitlilik göstermesi okulların geleceğini olumsuz etkileyecektir’ ifadesi ile ‘okullara alınan öğrenci sayısın fazla olması öğrenci yetiştirme sürecini hızlandırmaktadır’ ifadesine oldukça katıldıkları, ‘öğrenci girdisi ile istihdam durumu arasında orantısızlık bulunmaktadır’, ‘kamu kurumlarında istihdam alanı kısıtlıdır’ ve ‘özel kuruluşlarda istihdam alanı kısıtlıdır’ ifadelerine de tamamen katıldıkları görülmüştür. Gruplar arası ve grup içi değerlerde ise herhangi bir anlamlı farklılık ortaya çıkmamıştır (p>0,05)

Bovine aortic arch and idiopathic pulmonary artery aneurysm associated with bronchial compression

AbstractThe left common carotid artery originating from the brachiocephalic trunk is termed the bovine aortic arch. Although it is the third most-common normal variant found in 9% humans, the origin of this term remains unclear. Until now, It has not been reported in the literature bovine aortic arch togetherness with pulmonary aneurysm and bronchial compression. Herein, we present a case with bovine aorta arch and pulmonary artery aneurysm associated with bronchial compression, which is incidentally detected by X-ray film. A 56-year-old Caucasian female admitted to the cardiology clinic with complaint of chest pain. Physical examination was unremarkable. Blood biochemistry values and cardiac markers were in normal range. Chest radiography revealed a widened mediastinum and prominent pulmonary conus with no active pulmonary disease. A subsequent transthoracic echocardiography revealed left ventricular hypertrophy, left atrial enlargement (diameter: 41mm), mild mitral and tricuspid valve insufficiency, dilatation of main pulmonary artery (parasternal short-axis view diameter: 33mm), normal pulmonary artery pressure and normal left ventricular systolic function. Computed tomography revealed bovine aortic arch associated with pulmonary artery aneurysm (diameter: 53mm). And left main bronch of trachea was critically squeezed by aortic arch. Aortic and pulmonary vascular anomalies should be considered in patients with chest pain. And, identification with imaging modalities is important for prevention of chronic and irreversible complications