Genotoxic effects of indium tin oxide (ITO) were investigated on root cells of Allium cepa by employing both Allium and Comet assays. A. cepa roots were treated with the aqueous dispersions of ITO at 5 different concentrations (12.5, 25, 50, 75, and 100 ppm) for 4 h. Exposure of ITO significantly increased mitotic index, and total chromosomal aberrations by the Allium test. While chromosome laggards, stickiness, disturbed anaphase-telophase and anaphase bridges were observed in anaphase-telophase cells, c-metaphase and binuclear cells were observed in other cells. A significant increase in DNA damage was also observed at all concentrations of ITO by the Comet assay. These results indicate that ITO exhibits genotoxic activity in A. cepa root meristematic cells.

Accurate prediction of nitrogen oxide, soot, carbon monoxide and unburned hydrocarbon emissions from diesel engines plays a crucial role during the design and development phases of vehicle powertrain systems due to increasingly more strict emission legislation. Undoubtedly, generating accurate and robust emission prediction methods will serve to global optimization of engine components at very early stages of engine development. Engine component selection, accurate specific fuel consumption prediction and defining the correct exhaust gas recirculation strategy (low and mid-high) can only be performed via accurate and fast emission prediction. There are many possible ways of emission prediction in the literature, such as three-dimensional computational fluid dynamics, stochastic reactor, semi-empirical, phenomenological models and neural networks. However, these prediction methods either need excessive test data or simulation duration. However, using one-dimensional simulation tools is a faster way of emission prediction, but has low accuracy. In this study, it is aimed to develop a fast NO x emission prediction methodology by utilizing one-dimensional models generated in GT-Suite software. Two different heavy-duty engines are modelled, and the models are correlated with test data. An NO x emission prediction methodology is developed with the 9-L heavy-duty diesel engine model. Extended Zeldovich mechanism included in the software is tuned via embedding different calibration multiplier maps. Comparison of simulation results with test data shows that turbine inlet temperature, in-cylinder maximum temperature, maximum pressure, load, CA50, exhaust gas recirculation rate and fuel-air ratio are the most critical map parameters for enhanced emission prediction capability. The methodology developed is applied to the 12.7-L engine with these selected map parameters. The results show that the methodology can be used to predict NO x values with high speed and sufficient accuracy for different heavy-duty diesel engine variants.

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The purpose of this study is to determine the effectiveness of an IT certificate program that contributes to the career development of individuals in terms of gaining 21st century skills, given the increasing competitive conditions of globalization process and developments in Information Technologies (IT). This study covers the Cisco Certified Network Associate (CCNA) Certificate Program in Vocational and Technical High Schools in collaboration with Cisco Networking Academy, one of the important institutions among IT certification programs. This certificate program provides training to students in the department of information technologies and electrical-electronics technologies in vocational high schools in order to meet the labor demands in the field of computer networks technology in Turkey. This certificate program is a comprehensive study starting in 2011-2012 academic year and completed in two years. However, the scope of this study is limited to the comparison of demographic characteristics and 21st century skill levels of students participating and non-participating in the certificate program. The study was conducted with 1453 students and the majority of these students were male. According to the findings of the study, it was concluded that the students who participated in the certificate program had a high level of skills in terms of 21st century skills. In addition, there was no effect of gender among students participating in technology-based certificate programs. ​Extended English summary is in the end of Full Text PDF (TURKISH) file. Özet Küreselleşme sürecinin artan rekabetçi koşulları ve Bilgi Teknolojilerinde (BT) yaşanan gelişmeler göz önüne alındığında, bireylerin kariyer gelişimlerine katkı sağlayan sertifika eğitim programlarının 21. yüzyıl becerilerinin kazandırılması bakımından ne derece etkili olduğunun ortaya konması bu çalışmanın amacını oluşturmaktadır. Bu çalışmada, BT sertifika eğitim programları arasında önemli kuruluşlardan biri olan Cisco Networking Academy işbirliği ile Mesleki ve Teknik Liselerde gerçekleştirilen Cisco Certified Network Associate (CCNA) Sertifika Programı ele alınmıştır. Bu sertifika programı, Türkiye’deki bilgisayar ağları teknolojisi alanındaki işgücü taleplerini karşılamak maksadıyla meslek liselerinin bilişim ve elektrik-elektronik teknolojileri alanlarındaki öğrenciler için eğitimler düzenlemektedir. Bu sertifika eğitim programının değerlendirilmesi 2011-2012 eğitim-öğretim yılında başlayan ve iki yılda tamamlanan kapsamlı bir çalışmadır. Ancak mevcut çalışmanın kapsamı, eğitim programının birinci yılında sertifika programına katılan öğrenciler ile katılmayan öğrencilerin demografik özellikler ve 21. yüzyıl beceri düzeyleri bakımından karşılaştırılması ile sınırlıdır. Araştırma toplamda 1453 öğrenci ile gerçekleştirilmiş olup bu öğrencilerin çoğunluğu erkeklerden oluşmaktadır. Çalışmanın bulgularına göre, sertifika programına katılan öğrencilerin katılmayan öğrencilere göre 21. yüzyıl becerileri bakımından birçok düzeyde yüksek becerilere sahip oldukları ve teknoloji ağırlıklı sertifika eğitim programlarına katılan öğrenciler arasında cinsiyete bağlı dezavantajlı grupların oluşmadığı sonucuna ulaşılmıştır.

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