ITS DNA sequence utility for the relationship of Heracleum L. (umbelliferae) genus

31st Congress of the Federation-of-European-Biochemical-Societies (FEBS) -- JUN 24-29, 2006 -- Istanbul, TURKEYWOS: 000238914001442…Federat European Biochem So

Reconceptualised family resemblance approach to nature of science in pre-service science teacher education

A recent framework on nature of science (NOS) is the Family Resemblance Approach (FRA). FRA presents NOS as a cognitive-epistemic and social-institutional system with a set of categories: aims and values, scientific methods, scientific practices, scientific knowledge and social-institutional aspects of science. Although FRA has been problematised philosophically and its implications for science education have been considered by science educators, its empirical adaptations in science education are limited. In order to illustrate the educational adaptations of FRA, we refer to Reconceptualised Family Resemblance Approach to Nature of Science or RFN. We present a study based on a funded pre-service science teacher education project whose aim was to design, implement and evaluate the impact of RFN strategies. Fifteen pre-service teachers participated in a 14-week teacher education intervention that infused RFN. A 70-item questionnaire was designed to investigate the outcomes of the teacher education intervention. Individual interviews with pre-service teachers were also conducted. Quantitative and qualitative data analysis suggest that the teacher education intervention had an overall significant impact on pre-service teachers’ views of NOS. The paper contributes to the understanding of how NOS can be incorporated in science teacher education using a new orientation to NOS based on FRA

Reconceptualised family resemblance approach to nature of science in pre-service science teacher education

A recent framework on nature of science (NOS) is the Family Resemblance Approach (FRA). FRA presents NOS as a cognitive-epistemic and social-institutional system with a set of categories: aims and values, scientific methods, scientific practices, scientific knowledge and social-institutional aspects of science. Although FRA has been problematised philosophically and its implications for science education have been considered by science educators, its empirical adaptations in science education are limited. In order to illustrate the educational adaptations of FRA, we refer to Reconceptualised Family Resemblance Approach to Nature of Science or RFN. We present a study based on a funded pre-service science teacher education project whose aim was to design, implement and evaluate the impact of RFN strategies. Fifteen pre-service teachers participated in a 14-week teacher education intervention that infused RFN. A 70-item questionnaire was designed to investigate the outcomes of the teacher education intervention. Individual interviews with pre-service teachers were also conducted. Quantitative and qualitative data analysis suggest that the teacher education intervention had an overall significant impact on pre-service teachers’ views of NOS. The paper contributes to the understanding of how NOS can be incorporated in science teacher education using a new orientation to NOS based on FRA

Ternary Alloys Product by P/M Technique

In this study, Al matrix composites consisting of different amounts of Zn, Cu, and Mg were produced using the powder metallurgy technique. In the alloying, powders were ball milled for 120 min via mechanical alloying. After alloying process, the powders were pressed at 800 MPa at room temperature. Sintering (2 h at 600 degrees C in argon atmosphere), solution treatment (2 h at 480 degrees C), and aging processes (3, 6, 9, and 12 h, respectively, at 120 degrees C) were applied to the samples. The hardness and tribo-metallurgy properties of the products were investigated. After sintering, the hardness values of the three alloys were close to each other; however, the solution treatment after sintering caused the hardness values to increase significantly. It was determined that the Al-2Zn-5Cu-4Mg alloy had the highest hardness increase with the 6-h aging heat treatment. The wear resistance of the materials in all the compositions had increased. The highest wear resistance and lowest friction coefficient were obtained for the Al-2Zn-5Cu-4Mg alloy with the 6-h aging heat treatment.C1 [Kaplan, Yavuz] Pamukkale Univ, Fac Technol, Dept Mech & Mfg Engn, Denizli, Turkey.[Aksoz, Sinan] Pamukkale Univ, Fac Technol, Dept Met & Mat Engn, Denizli, Turkey.[Ada, Hakan] Kastamonu Univ, Dept Mech Engn, Fac Engn & Architecture, Kastamonu, Turkey.[Ince, Emre; Ozsoy, Serkan] Kastamonu Univ, Inst Sci & Technol, Kastamonu, Turkey

Perceptions of nature of science emerging in group discussions: A comparative account of pre-service teachers from Turkey and England

The paper presents a study about pre-service science teachers’ perceptions of the Nature of Science (NOS). Although there is a substantial amount of research on NOS in science teacher education, international comparative accounts particularly of in-depth qualitative data emerging from group discussions are fairly minimal. The primary aim of the research was to determine the changes of pre-service science teachers’ NOS perceptions following group discussions in two different national contexts: Turkey and England. Two groups of pre-service teachers from Turkey were contrasted with two groups of pre-service teachers from England. The group discussions were structured with a set of steps. In the first step, the participants were asked to reflect about NOS and record their key ideas on sticky notes. Subsequently, they were presented with a visual framework of NOS, and they were asked to situate their own ideas from the sticky notes in this image. Verbal data from group discussions were investigated by qualitative methodology using thematic analysis. The findings suggest that both groups of pre-service teachers initially focused on epistemic-cognitive aspects of NOS but their ideas became more nuanced in providing some examples about social and institutional dimensions of NOS following the introduction of the NOS image. The study contributes to the understanding of how pre-service teachers view NOS and illustrates how NOS can potentially be incorporated into group discussions in science teacher education

Protective effects of an extract of propolis in scopolamine-induced cognitive impairment in rats

28th Congress of the European-College-of-Neuropsychopharmacology (ECNP) -- AUG 29-SEP 01, 2015 -- Amsterdam, NETHERLANDS[No Abstract Available]European Coll Neuropsychopharmaco

Dependence of Electrical Resistivity on Temperature and Sn Content in Pb-Sn Solders

WOS: 000287861900012Pb(100-x)-Sn-x solders (x = 5 wt.%, 10 wt.%, 20 wt.%, 35 wt.%, 50 wt.%, 60 wt.%, 61.9 wt.%, and 95 wt.%) were directionally solidified upward with a constant growth rate (V = 37.4 mu m/s) in a temperature gradient (G = 4.8 K/mm) in a Bridgman-type growth apparatus. The variations of electrical resistivity (rho) with temperature in the range of 323 K to 423 K for the directionally solidified Pb-Sn solders were measured. The present measurements indicate that the electrical resistivity of the directionally solidified Pb-Sn solders increases with increasing temperature, whereas the resistivity of the Pb-Sn solders decreases with increasing Sn content. The dependency of the Lorenz number (L) on temperature and Sn content for the Pb-Sn solders was also investigated based on the Wiedemann-Franz law by using the measured values of the thermal (K) and electrical (sigma) conductivity for the same alloys.Nigde University Scientific Research Project Unit [FEB 2008/12]This project was supported by Nigde University Scientific Research Project Unit under Contract No. FEB 2008/12. The authors are grateful to Nigde University Scientific Research Project Unit for their financial support

Dependency of the thermal and electrical conductivity on the temperature and composition of Cu in the Al based Al-Cu alloys

WOS: 000282242200055The variations of thermal conductivity with temperature for Al-[x] wt.% Cu, x = 3, 6, 15 and 24 alloys were measured by using a radial heat flow apparatus. The variations of electrical conductivity of solid phases versus temperature for the same alloys were determined from the Wiedemann-Franz and Smith-Palmer equations by using the measured values of thermal conductivity. From the graphs of thermal and electrical conductivity versus temperature, the thermal conductivity of the solid phases at their melting temperatures, and the thermal temperature and the electrical coefficients for the same alloys were obtained. Dependency of the thermal and electrical conductivity on the composition of Cu in the Al based Al-Cu alloys were also investigated. According to present experimental results, the thermal and electrical conductivity of Al-[x] wt.% Cu, x = 3, 6, 15 and 24 alloys linearly decrease with increasing the temperature and composition of Cu. The enthalpy of fusion and the specific heat change during the transformation for the same alloys were determined from cooling trace during the transformation from eutectic liquid to eutectic solid by means of differential scanning calorimeter (DSC). (c) 2010 Elsevier Inc. All rights reserved.Nigde University Scientific Research Project Unit [FEB 2008/12]This project was supported by the Nigde University Scientific Research Project Unit under Contract No: FEB 2008/12. Authors would like to thank to the Nigde University Scientific Research Project Unit for their financial support