Kafkas University is a public higher educational institution established on July 11, 1992, in Kars, Eastern Anatolia in Turkey. It has six faculties, three institutes, three colleges, four vocational colleges and several research and application centers. The university campus is situated 3.5 km southwest of Kars. Kafkas is Turkish for Caucasus. Wikipedia.
Gunbas N.,Kafkas University
Journal of Computer Assisted Learning | Year: 2015
The purpose of this study was to investigate the effect of a computer-based story, which was designed in anchored instruction framework, on sixth-grade students' mathematics word problem-solving achievement. Problems were embedded in a story presented on a computer as computer story, and then compared with the paper-based version of the same story and to a condition that presented the problems as typical, isolated word problems (i.e., a non-story condition including only problems). One hundred twenty-eight sixth-grade students from two public middle schools in Turkey participated in this study. In a pretest-posttest experimental design, students were randomly assigned to one of the treatment groups mentioned earlier in which they solved the same mathematics word problems. A one-way analysis of covariance was used to analyse students' achievement in the treatment groups. The results indicated that students who solved the problems in the computer story treatment had significantly higher achievement scores than students who solved the problems in the paper story and isolated word problems treatments. In addition, the story was found to be significantly more effective than the non-story treatment when it was presented on computer. © 2014 John Wiley & Sons Ltd.
Gunes F.,Kafkas University
Plant Systematics and Evolution | Year: 2011
In this study, the pollen morphology of 18 wild taxa of Lathyrus L. grown in Turkey: L. pallescens (Bieb.) Koch, L. brachypterus Cel., L. haussknechtii Sirj., L. karsianus P. H. Davis, L. satdaghensis P. H. Davis, L. nivalis Hand.-Mazz, L. atropatanus (Grossh.) Sir., L. armenus (Boiss. and Huet) Sirj., L. cyaneus (Stev.) Koch var. cyaneus, L. cyaneus var. pinnatus Davis, L. digitatus (Bieb.) Fiori, L. tukhtensis Czecz., L. variabilis (Boiss. and Ky.) Maly, L. spathulatus Cel. L. elongatus (Bornm.) Sirj., L. cilicicus Hayek and Siehe, L. boissieri Sirj., and L. bitlisicus Peşmen was examined by light microscopy and scanning electron microscopy. The pollen grains were 3-zonocolporate, of spheroidal-subprolate-prolate (P/E = 0.957-1.252) types, and medium in size. Equatorial view: rectangular or elliptical-obtuse-convex, polar view: circular, triangular or quinquangular-obtuse-convex. The smallest pollen grains belonged to L. elongatus (P = 36.972/E = 38.636) and the largest to L. cyaneus var. cyaneus (P = 46.332/E = 32.864). The ornamentation was perforate-foveolate or slightly reticulate. Some photographs included in this work were taken using both light microscopy and scanning electron microscopy. © 2011 Springer-Verlag.
Gunes F.,Kafkas University
International Journal of Agriculture and Biology | Year: 2011
In this study, 10 wild species of genus Lathyrus grown in Turkey L. niger (L.) Bernh. subsp. niger, L. palustris L. subsp. palustris, L. tuberosus L., L. sphaericus Retz., L. setifolius L., L. clymenum L., L. nissolia L., L. aphaca L. var. aphaca, L. aphaca var. affinis (Guss.) Arc, L. aphaca var. bifilorus Post were examined for pollen morphology. Preparations were made using non-acetolysed and Erdtman methods. The shapes, apertureties, structures and sculptures of pollen were observed by using light microscope (LM). The pollen grains were 3-zonocolporate, of spheroidal-subprolate-prolate types (P/E=1.028-1.573), medium to large in size. Equatorial view; elliptical-obtuse-convex, polar view; circular to triangular-obtuse-convex. The smallest pollen grains belong to L. nissolia (P=32.791/E=24.747 in non-acetolysed, P=40.508/E=28.444 in Erdtman) and the longest to L. clymenum (P=52.418/E=35.815 in non-acetolysed, P=58.604/E=46.332 in Erdtman) taxa. The ornamentation was reticulate or slightly perforate-foveolate. The pollen morphology of species was also studied using a scanning electron microscope (SEM). In addition, some photographs included in this work were taken using both LM and SEM. © 2011 Friends Science Publishers.
Beytut E.,Kafkas University
Journal of Comparative Pathology | Year: 2010
The present study investigated the expression of pulmonary surfactant proteins (surfactant protein [SP]-A, SP-B, proSP-C), thyroid transcription factor-1 (TTF-1), proliferating cell nuclear antigen (PCNA) and the infiltration of CD3 + T and CD79αcy + B lymphocytes into the lungs of 10 lambs naturally infected with sheep pox virus. Microscopical examination detected marked epithelial hyperplasia, sheep pox cells and neutrophilic infiltration in pock nodules. Immunohistochemistry demonstrated intense expression of SPs in the cytoplasm of the hyperplastic type II pneumocytes in the nodular pock lesions. These cells displayed a gland-like arrangement. The hyperplastic and the normal bronchiolar epithelium did not express SPs. The nuclei of the hyperplastic and normal type II pneumocytes labelled positively for TTF-1. Strong PCNA positivity indicated epithelial cell proliferation in the pock nodules. Moderate to abundant numbers of CD3 + T cells, but few CD79αcy B lymphocytes, were detected in the pock lesions. Transmission electron microscopy revealed that the hyperplasia in the pock nodules comprised predominantly type II pneumocytes and that the sheep pox cells and epithelial cells contained virus particles in their cytoplasm. The results of this study show that sheep pox virus induces marked proliferation of type II pneumocytes and bronchiolar epithelial cells and that the lung lesions in diseased lambs are mainly proliferative. © 2010 Elsevier Ltd.
Yuksek M.,Kafkas University
Optics Communications | Year: 2012
The amorphous semiconductor InSe thin films were deposited by the thermal evaporation method. The nonlinear refraction index behaviors of amorphous semiconductor InSe thin films were investigated with closed aperture Z-scan experiments by using laser sources which have nanosecond, picosecond and femtosecond pulse durations. The results of closed aperture Z-scan experiments have showed that nonlinear refraction index varied with film thicknesses and/or pulse durations of pump laser. By increasing the film thicknesses, the sign of nonlinear refraction indexes of amorphous semiconductor InSe thin films has changed from negative to positive under nanosecond and picosecond pulse durations excitations, while under femtosecond pulse duration excitation this behavior has not been observed. © 2012 Elsevier B.V. All rights reserved.