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An Investigation of Transition Flow in Porous Media by Event Driven Molecular Dynamics Simulation
No full textAim of this study is to investigate the properties of mono-atomic gas flow through the porous medium by using Event-Driven Molecular Dynamics (EDMD) simulation in the transition regime. The molecules and the solid particles forming the porous structure were modelled as hard spheres hence molecule trajectories, collision partners, interaction times and post-collision velocities were calculated deterministically. The porous medium is formed of spherical particles suspended in the middle of the channel and these particles are distributed into the channel in a regular cubic array. Collisions of gas molecules with porous medium were provided by means of the specular reflection boundary condition. A negative pressure boundary condition was applied to the inlet and outlet of the porous media to ensure gas flow. Porosity, solid sphere diameter and Knudsen number (Kn) were initially input to the simulation for different Cases. Thus, the effects of these parameters on mass flow rate, dynamic viscosity, tortuosity and permeability were calculated by EDMD simulation. The results were compared with the literature and were found to be consistent
Investigation of the Higher Education Students' Participation in Quality Assurance Processes Based on the Theory of Planned Behaviour: A Case of Turkey
No full textThis study aims to investigate Turkish higher education students' participation behaviours in quality assurance systems. The data were collected from 113 students through a semi-structured qualitative questionnaire developed based on the theory of planned behaviour. The data were analysed under three main themes: feelings, subjective norms and perceived behavioural control. According to the results, students generally had positive opinions concerning their feelings about the quality assurance system and had positive subjective norms. However, the results for these two aspects indicated implementation-based passive participation rather than decision-based active participation. Challenges in behavioural control and ways of coping with these challenges were observed. The overall results has revealed the behavioural basis of student participation in quality assurance processes. In addition, the results can contribute to policy improvement processes in the higher education system and quality assurance activities for higher education institutions
The Investigation of Displacement Demands of Single Degree of Freedom Models Using Real Earthquake Records Compatible With Tbec-2018
No full textAdvances in earthquake engineering play a role in the development of seismic codes all over the world. The new version of Turkish Building Earthquake Code (TBEC) has also been published in 2018. Thanks to the technological developments, real acceleration records to be used in dynamic analysis of structures have been easily accessible. In this study, the variation of maximum displacement demands of single degree of freedom (SDOF) systems determined via dynamic analysis by using real earthquake records compatible with TBEC are investigated. For this purpose, 120 SDOF systems which represent behavior of variety of structural topologies were created by combination of different lateral strength capacity ratios, structural periods, hysteretic models and post-yield stiffness ratios. In order to obtain ground motion records, two different level of seismic intensity level and three different local soil classes are considered. 30 real ground motion record sets for each seismic intensity level and local soil class are used for detailed assessment of tendency and variation of maximum displacement demands. Results indicated that (a) effect of different hysteretic models on displacement demands is negligible, (b) the mean displacement demands are more conservative than median displacement demands for the sets, (c) displacement demand variation of the sets are high and not evenly distributed, (d) the variation of the demands changes randomly depending on local soil class and earthquake level, (e) lateral strength ratio and post-yield stiffness are efficient on the variation of the demands
Determining the Expression Levels of Circulating Tumour Cell Markers in Canine Mammary Tumours
No full textDetection of the circulating tumour cells (CTC) in dogs with a mammary tumour is a useful tool to reveal the micrometastases long before metastases are recognised clinically. The aim of this study was to evaluate the association of the epidermal growth factor receptor (EGFR), claudin 7 (CLND7) and epithelial cell adhesion molecule (EPCAM) with the clinical indices and to reveal the diagnostic importance of these biomarkers in canine mammary tumours (CMTs). Peripheral blood (PB) samples were collected from 45 bitches (group MT) which had single mass with malignant epithelial tumours and 9 healthy bitches (group H). Real time PCR (rt-PCR) was performed to determine the expression levels of EGFR, CLDN7, and EPCAM. Mean values of EGFR and CLDN7 expressions were significantly higher in group MT compared to group H (P < 0.01 and P < 0.001, respectively). The expression level of CLDN7 was positively correlated with EGFR and EPCAM (P < 0.001 and P < 0.05, respectively). The EPCAM expression was associated with increased tumour size (P < 0.05) and EPCAM tended to decrease in the presence of skin ulceration on tumour (P = 0.05). Furthermore, expression levels of EGFR in intact dogs were significantly higher compared to spayed dogs in group MT (P < 0.01). The EGFR expression was significantly higher in the presence of metastases (P < 0.05). Also, increased EGFR was determined in grade 2 compared to grade 1 (P < 0.05). In conclusion, these results show that EGFR, CLDN7, EPCAM markers are measureable in PB and they may provide valuable information about the clinical pathophysiology of CMT
Iran's Role In Turkey's Irregular Migration Issues
No full textBu makalenin amacı Türkiye’nin düzensiz göç probleminin büyük bir bölümünün İran üzerinden gerçekleştiğini ortaya koymak ve bu problemde İran’ın göç politikalarının etkisini sorgulamaktır. Sorgulama dört aşamada yapılacaktır. Öncelikle göç olgusunun tanımı yapılacak, bu olgu kavramsal ve kuramsal açıdan tanıtılacaktır. Ardından Türkiye’nin düzensiz göç problemi ele alınıp bu sorunda İran’ın ve kaynak ülkelerin durumları ortaya koyulacaktır. Üçüncü aşamada İran’ın göçmen nüfusu hakkındaki veriler analiz edilip, göçmenlere yönelik politikaları ele alınacaktır. Sonuç bölümünde ise İran’ın politikaları ile Türkiye’ye yönelen düzensiz göç problemi arasındaki ilişki ortaya koyularak sorunun çözümünde rol alacak bazı politika önerileri yapılacaktır. Çalışmada ulaşılan sonuç; Türkiye’nin düzensiz göç problemi ile İran’ın göç politikalarının yakın bir ilişki içinde olduğu, bu problemin İran ile geliştirilecek ortak politikalarla azaltılabileceği ya da çözüme kavuşturulabileceğidir
Search for the reaction e(+) e(-) -> chi(cJ)pi(+)pi(-) and a Charmoniumlike Structure Decaying to chi(cJ)pi(+/-) between 4.18 and 4.60 GeV
No full textWe search for the process e(+)e(-) -> chi(cJ)pi(+) pi(-) (J = 0, 1, 2) and for a charged charmoniumlike state in the chi(cJ)pi +/- subsystem. The search uses datasets collected with the BESIII detector at the BEPCII storage ring at center-of-mass energies between 4.18 GeV and 4.60 GeV. No significant chi(cJ)pi(+) pi(-) signals are observed at any center-of-mass energy, and thus upper limits are provided which also serve as limits for a possible charmoniumlike structure in the invariant chi(cJ)pi +/- mass
Search for the Charged Lepton Flavor Violating Decay J/psi -> e tau
No full textA search for the charged lepton flavor violating decay J/psi -> e(+/-)tau(-/+) with tau(-/+) -> pi(-/+)pi(0)nu(tau) is performed with about 10 x 10(9) J/psi events collected with the BESIII detector at the BEPCII. No significant signal is observed, and an upper limit is set on the branching fraction B(J/psi -> e(+/-)tau(-/+)() < )7.5 x 10( )(-8) at the 90% confidence level. This improves the previously published limit by two orders of magnitude
Microplastic Inventory in Sediment Profile: A Case Study of Golden Horn Estuary, Sea of Marmara
No full textAssessment of microplastics (MPs) in sediment cores is necessary to unveil global plastic pollution since most of the plastic litter might have been stored in sediment columns. In the current study, MPs inventory was determined in a 105 cm sediment core, collected in the Golden Horn Estuary, Sea of Marmara. Radiodating of sediment profile by using naturally occurring Pb-210 and fission product Cs-137 allowed us to couple the retrospective of global MP production to sediment MPs inventory. More than 90% of total MPs inventory was found in the deep layer of the sediment column (below 15 cm). Small MPs (20-200 mu m) were more abundant than large ones (200-4000 mu m). Elevated concentrations of MPs were attributed to industrial and municipal effluent of Istanbul metropolitan. On a local scale, this study suggests that the Golden Horn Estuary was polluted with MPs before the 1950s, and the abundance of MPs reached a maximum in the 1980s. We also propose on a global scale that "the missing" plastics might have been buried in deep sediment and radiodating of sediment is useful to reveal their historical input records
An Analysis of the Stock Market Volatility Spread in Emerging Countries
Get PDFThis article provides results on the volatility spread for stock markets in emerging economies. Empirical studies on determining or predicting volatility in national and international financial markets provide information for investors. The aim of this study is also to analyze volatility spreads from the United States of America, France, Germany, Japan Turkey, China, India, Indonesia from emerging markets within the scope of EGARCH models, which take into account the asymmetric effects using daily stock returns for the period of January 2008 - April 2020. The a symmetric effect parameter (λ or μt-i/ht-1) appears to be negative and statistically significant at 1% for all countries, except the Shanghai Composite Stock Exchange, China. This result shows that the asymmetric effect, or the leverage effect in other words, is valid in stock markets other than China. The volatility spreads from the Dow Jones Industrial Average Index – USA to Borsa Istanbul and the Shanghai Stock Exchange – China. Also, the S & P 500 Index – USA is significant on the volatility spread of the Borsa Istanbul and Shanghai Stock Exchange. The volatility spread between Jakarta Stock Exchange - Indonesia and Borsa Istanbul is two-way and mutual
The Attitudes of Cancer Patients with Nausea and Vomiting Symptoms to Complementary and Holistic Treatments: A Cross-Sectional Study
Get PDFThe study was performed to determine theattitude of cancer patients with symptoms of nausea and vomiting towards complementary and holistic treatment. Material and Methods:The study sample included the 138 cancer patients with 3 or more nausea and vomiting according to Visual Anolog Scale were included inthe study. Information Form, Attitudes towards Holistic Complementary and Alternative Medicine Scale, The Rhodes Index of Nausea, Vomiting, and Retching were used as data collection of this study. Results:Cancer patients were found to have a positive attitude towards complementary and holistic therapy. Although cancer patients participatingin the study often experienced nausea and vomiting, symptom distresswas also low. There was a positive correlation between symptom frequency and the symptom occurrence and holistic health dimensions(p˂0.05). Moreover, a positive correlation was found between thesymptom occurrence of the patients and their attitudes towards alternative medicine (p˂0.05). Conclusion: Cancer patients have a positiveattitude towards complementary and holistic therapy in relieving thesymptoms of nausea and vomiting. It is recommended to create guidelines for determining effective strategies and using them properly inmixed therap