Ahi Evran University

About: Ahi Evran University is a education organization based out in Kırşehir, Turkey. It is known for research contribution in the topics: Density functional theory & Ab initio. The organization has 842 authors who have published 2270 publications receiving 21904 citations.

Examining Argumentation Skills of Preservice Science Teachers in Terms of their Critical Thinking and Content Knowledge Levels: An Example Using GMOs*

Abstract: The aim of this study was to examine the argumentation skills of preservice science teachers on genetically modified foods during an argumentation process. Within case study research methodology, this study was carried out with 20 preservice science teachers identified through convenience sample from science education department. Knowledge Test for GMOs, Watson-Glaser Critical Thinking Appraisal and semi-structured interview questions were used to collect data. Findings showed that the groups with high level genetically modified food knowledge tended to use more qualified rebuttal and evidence. On the other hand, the groups with high level critical thinking skills were apt to exploit more qualified warrant, counter-argument, rebuttal and evidence. The research findings revealed that knowledge level and critical thinking skills are influential on argumentation skills. It was concluded that content knowledge is associated with self-efficacy and motivation in argumentation. However, critical thinking skills are associated with focusing, open-mindedness, understanding opposing ideas, and finding missing parts. In the light of this information, some suggestions was made for the development of knowledge and critical thinking skills for policy makers and educational scientists who have designed a teacher training program.

Therapeutic effects of statins on chromosomal DNA damage of dyslipidemic patients.

Abstract: Statins are a group of cholesterol lowering drugs and frequently used in the therapy of dyslipidemia. Our knowledge of the impact of statin therapy on DNA damage is as yet rudimentary. In this stud...

Effect of formaldehyde gas adsorption on the electrical conductivity of Pd-doped TiO2 thin films

Abstract: 0.5 wt% Pd-doped titanium oxide thin films were obtained by dip-coating on silicon substrates. The films were compacted by annealing in air at 300 and 500 °C. Temperature dependent electrical conductivity measurements were performed in the temperature range 373–623 K, in different environments (air, methane, acetone, ethanol, formaldehyde and liquefied petroleum gas), to test the films sensing gas properties. Formaldehyde was found to be the test gas that produces the most significant changes in the electrical conductivity of the studied films. This was the reason why it was chosen to investigate its effect on their electrical conductivity. A model was proposed, the model of the potential fluctuations at grain boundaries. A comparison between some parameters obtained in the proposed model was performed as a function of annealing temperature, and as a function of gas atmosphere. The values of the mean barrier height and the standard deviation were estimated to range between 0.336–0.588 eV and 0.175–0.199 eV, respectively. It was found that formaldehyde leads to a rather sharp decrease in the values of the barrier height and the standard deviation, and to an increase in the conductivity. We have observed the best sensing gas performance for the films annealed at 300 °C, comparing to their counterparts annealed at 500 °C, explained by the lowest values of the barrier energy height and the standard deviation.

Synthesis, Characterization, Computation of Global Reactivity Descriptors and Antiproliferative Activity of N-(4-nitrophenyl)Acrylamide

Abstract: In this article N-(4-nitrophenyl)acrylamide has been synthesized and characterized both experimentally and theoretically. The synthesized monomer was characterized experimentally by Fourier Transform Infrared, Nuclear Magnetic Resonance spectroscopic techniques and theoretically by Density Functional Theory and Time-Dependent Density Functional Theory methods at Coulomb Attenuated Method level. To investigate the natural toxicity and reactivity of the title molecule optimized at the Density Functional Theory/Coulomb Attenuated Method- Becke three-parameter Lee-Yang-Parr level, the chemical reactivity descriptors were calculated based on the rotational barriers. Using the Parr formula, the interaction between N-(4-nitrophenyl)acrylamide molecule and nucleic acid bases (adenine, thymine, cytosine, uracil and guanine) phenylalanine and histidine an Aryl Hydrocarbon hydroxylase receptors were investigated. Charge transfer that is important in the formation of chemically bonded adducts causing cancer has been calculated quantitatively. In addition, in vitro cytotoxicity of N-(4-nitrophenyl)acrylamide on HeLa cell lines has been studied. It has been found that the half maximal inhibitory concentration value of N-(4-nitrophenyl)acrylamide is 1 mM in HeLa cells. Our results show that N-(4-nitrophenyl)acrylamide, an acrylamide-based molecule that is accepted as toxic by the World Health Organization, has low toxicity on cancer cells by experimental study and, in theory, it has low toxicity according to calculations of reactivity descriptors, therefore can be used for biomedical research.

Category theoretical view of I -cluster and I -limit points of subsequences

Abstract: We study the concepts of I-limit and I-cluster points of a sequence, where I is an ideal with the Baire property. We obtain the relationship between I-limit and I-cluster points of a subsequence of a given sequence and the set of its classical limit points in the sense of category theory.