Identification of salt stress responsive protyeins in wild sugar beet (Beta maritima) using 2D-page with MALDI-TOF/TOF system

Thesis (Master)--Izmir Institute of Technology, Molecular Biology and Genetics, Izmir, 2012Includes bibliographical references (leaves: 30-34)Text in English; Abstract: Turkish and Englishxiii, 55 leavesHigh salinity is one of the abiotic stresses, which affects the homeostasis, growth and productivity of plants. In plants, uptake of the non-essential salt ions negatively affects the anatomy, physiology and metabolism, changes the osmotic balance in cells and causes abundant dehydration. In this case, higher plants develop salt tolerance mechanisms such as induction of related signaling pathways, effluxion of salt ions, accumulation of these toxic ions in their vacuoles, activation of their detoxification mechanisms and production of osmoprotectans. In this study, identification of salt responsive proteins in moderately halophyte wild type sugar beet Beta vulgaris ssp. maritima was aimed. In order to investigate the protein-based natural stress tolerating mechanisms, plants were exposed to 150 mM NaCl and total proteins were extracted. Differentially expressed proteins were identified by proteomic approaches including MALDI-TOF/TOF mass spectrometry combined two dimensional polyacrylamide gel electrophoresis. The results revealed that enzymatic antioxidants and secondary members of antioxidative pathways are responsive in salt stress. In conclusion, these detected proteins demonstrate that antioxidative system may be the major defense mechanism in halophytic plants

Quasi-static crushing behavior of nomex honeycomb filled thin-walled aluminum tubes

Thesis (Master)--Izmir Institute of Technology, Materials Science and Engineering, Izmir, 2008Includes bibliographical references (leaves: 78-81)Text in English; Abstract: Turkish and Englishxiv, 96 leavesThe experimental and numerical studies presented in this thesis were focused on the experimental and numerical quasi-static crushing behavior of Nomexl1 honeycomb filled thin-walled aluminum tubes. Nomexl1 honeycombs having different cell sizes (3.2, 4.8 and 6.4 mm) and the same density (48 kg/m3) were used to fill thin walled aluminum tube, 25 mm in diameter and 0.29 mm in thickness. Compression tests were conducted at quasi-static the strain rates of 1.64 10-2, 6.56 10-3 and 3.28 10-3 s-1. The results showed that the honeycomb cell size had a strong effect on the crushing behavior. Decreasing cell size increased crushing loads and the specific absorbed energy values of empty tubes. The highest strengthening effect of filling was found in 3.2 mm cell size honeycomb filled tubes. Although no effects of 4.8 and 6.4 mm cellsize honeycomb filling on the deformation mode of tube was observed (mixed), 3.2 mm cell size honeycomb filling changed the deformation mode to mixed/concertina. The numerical model of empty tube, 6.4 mm cell size honeycomb and 6.4 mm cell size honeycomb filled tube were performed using LS-DYNATM and ANSYSTM finite element analysis programs. To acquire maximum computational efficiency, a mesh optimization was done. The effect of the honeycomb cell wall thickness was also investigated numerically and shown to have a strong effect on the crushing behavior of honeycomb. The experimental and numerical studies conducted showed that 3.2 mm cell size Nomex® honeycomb might become an alternative to aluminum foam filler in thin walled tubes as long as the tube crushing load was comparable with honeycomb crushing load

An augmented reality learning toolkit for fostering spatial ability in mathematics lesson: Design and development

Previous research claimed that integration of augmented reality on educational settings helps to improve academic achievement of students in collaborative learning environments, as well as to improve their retention and ability to translate this within other environments. Since augmented reality is still considered relatively novel technology in educational fields, there is an inherent need for research-based guides to design effective and feasible augmented reality tools for school-based learning. The main aim of this study was therefore to design and develop an augmented reality learning toolkit to foster spatial ability in middle school students using mobile devices. The study was conducted in two parts, as preliminary research and a prototyping phase. The findings guided the characteristics for designing an augmented reality learning toolkit with a set of spatial tasks aimed at middle school students. In light of the results, it can be inferred that the students were able to use this designed toolkit to perform their spatial ability through given spatial tasks since the students encountered no technical difficulties with the final toolkit prototype, and that they were able to use the toolkit assuredly. In conclusion, the study showed that augmented reality seemed helpful in enhancing the usage of mobile devices, not just for the reading of books, communication or playing games, but also as a support mechanism for the learning of mathematics. Thus, the augmented reality toolkit developed in this study presents a new way for students and/or teachers to use mobile devices in the learning and teaching of mathematics

İlköğretim Öğretmen Adaylarının Matematiğe Yönelik Tutum ve Özyeterlik Algıları

The purpose of this study was to explore the effect of gender and grade level on preservice teachers’ self-efficacy beliefs and attitudes toward mathematics. The analysis was based on 358 elementary and middle school mathematics teachers enrolled in an undergraduate program at two public universities in Ankara. Results showed that there was no significant effect of gender and grade level of preservice teachers on their attitudes toward mathematics. On the other hand, results also revealed that there was found a significant effect of gender as males scored significantly higher than females in their mathematics self-efficacy and there was a significant effect of grade level as senior preservice teachers had the highest and sophomore had the lowest mathematics self-efficacy scores.  Bu çalışmanın amacı, öğretmen adaylarının matematiğe yönelik özyeterlik algıları ve tutumlarının cinsiyet ve üniversite sınıf seviyesine göre anlamlı bir fark oluşturup oluşturmadığını incelemektir. Çalışma, Ankara’nın ilköğretim birinci ve ikinci kademe matematik öğretmeni yetiştiren iki üniversitesinde öğrenim görmekte olan 358 öğretmen adayıyla gerçekleştirilmiştir. Çalışma sonunda, öğretmen adaylarının matematiğe yönelik tutumlarının cinsiyet ve üniversite sınıf seviyesine göre anlamlı bir fark göstermediği bulunmuştur. Diğer yandan ise, öğretmen adaylarının matematiğe yönelik özyeterlik algılarının cinsiyet ve üniversite sınıf seviyesine göre anlamlı bir fark gösterdiği, erkek öğrencilerin kız öğrencilere oranla anlamlı düzeyde daha yüksek ortalamaya sahip oldukları bulunmuştur. Sınıf seviyesine göre ise bulgular, son sınıf öğrencilerinin en yüksek, ikinci sınıf öğrencilerinin ise en düşük ortalamaya sahip olduklarını göstermiştir.

Fully decentralized and collaborative multilateration primitives for uniquely localizing WSNs

We provide primitives for uniquely localizing WSN nodes. The goal is to maximize the number of uniquely localized nodes assuming a fully decentralized model of computation. Each node constructs a cluster of its own and applies unique localization primitives on it. These primitives are based on constructing a special order for multilaterating the nodes within the cluster. The proposed primitives are fully collaborative and thus the number of iterations required to compute the localization is fewer than that of the conventional iterative multilateration approaches. This further limits the messaging requirements. With relatively small clusters and iteration counts, we can localize almost all the uniquely localizable nodes.This work was partially supported by The Scientific and Technological Research Council of Turkey (TUBITAK) Grant no. 106E071.Publisher's Versio

Sekizinci Sınıf Öğrencilerinin Yapılandırıcı Fen Öğrenme Ortamı Hakkındaki Algılarının İncelenmesi

The present study investigated 8 th grade students’ perceptions of actual and preferred constructivist science learning environments. Data were collected from 1152 students attending public elementary schools in Ankara using the Constructivist Learning Environment Survey (CLES). The CLES consists of two forms which are “Actual” and “Preferred”. While actual form assesses the current learning environment of the classroom and the preferred form assesses the students’ preferences about the learning environment. Results showed that students’ scores on the preferred form were significantly higher than those of the actual form on each scale (p<0.05). Students tended to prefer more constructivist learning environments in which they have more opportunities to relate science with the real world, communicate in the classroom, take role in the decision making process of what will go on in the lesson to be more beneficial for them, question what is going on in the lesson freely and experience the formulation of scientific knowledge.Bu çalışmada, sekizinci sınıf öğrencilerinin mevcut ve tercih ettikleri yapılandırıcı fen öğrenme ortamı hakkındaki algıları incelenmiştir. Veriler, 1152 sekizinci sınıf öğrencisinden Yapılandırıcı Öğrenme Ortamı Ölçeği kullanılarak toplanmıştır. Bu ölçek, “mevcut” ve “tercih edilen” öğrenme ortamını değerlendiren iki bölümden oluşmaktadır. Ölçeğin mevcut öğrenme ortamı bölümü, sınıflardaki şu anki fen bilgisi öğrenme ortamının yapılandırıcı öğrenme yaklaşımını ne kadar yansıttığını ölçerken, tercih edilen öğrenme ortamı bölümü ise öğrencilerin tercih ettikleri öğrenme ortamını ölçmektedir. Sonuçlar, ölçeğin her alt boyutu için tercih edilen yapılandırıcı öğrenme ortamı algılarının mevcut öğrenme ortamı algılarına göre daha yüksek değerlerde olduğunu göstermiştir (p<0.05). Öğrenciler, bilimin değişebilen yapısını ve günlük hayatla ilişkisini öğrenmede fırsatlar sunan, birbirleriyle tartışma imkânı sağlayan, sınıf içi etkinliklerin planlamasında karar verme mekanizmasında rol oynayan ve gerektiğinde kritik edebilen öğrenme ortamlarını tercih etmektedirler

Öğretmen Özyeterlik Ölçeği Türkçe Uyarlamasının Geçerlik ve Güvenirlik Çalışması

The purposes of this study can be listed as (a) describing the development of a parallel Turkish version of the Teachers’ Sense of Efficacy Scale (TSES), (b) obtaining evidence of the internal consistency reliabilities of scores on each of the three subscales and whole scale, and (c) providing evidence for the construct validity of the three-factor subscale scores through the use of confirmatory factor analysis and Rasch measurement. The participants in this study were 628 pre-service teachers from six different universities located in four major cities in Turkey. The findings of the study provided evidence for the reliability and validity of the Turkish version of the TSES with the sample of Turkish pre-service teachers. These findings suggested that the Turkish version of the TSES can be used with Turkish pre-service teachers.Bu çalışmanın amacı, Tschannen-Moran ve Wool folk Hoy tarafından geliştirilen öğretmenlerin özyeterlik inançlarına yönelik ölçeğin Türkçeye adapte edilmesidir. Ayrıca, bu ölçek için güvenirlik ve doğrulayıcı faktör analizi ile Rasch yöntemi kullanılarak geçerlilik çalışmalarının yapılması hedeflenmiştir. Çalışmaya, Türkiye’nin dört büyük şehrindeki altı farklı üniversiteden 628 öğretmen adayı katılmıştır. Bulgular bize Türk öğretmen adayı örneklemi için geliştirilen Türkçe “öğretmen özyeterlik ölçeği”nin güvenirlik ve geçerliği hakkında deliller sunmaktadır