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Alterations in Niban Gene Expression as a Response to Stress Conditions in 3t3-L1 Adipocytes
(Springer, 2020) Cevik, Mehtap; Gunduz, Meliha Koldemir; Deliorman, Gokce; Susleyici, Belgin
Adipocyte death is important in obesity development. Understanding and prevention of adipocyte deaths may be a molecular approach in the treatment. In the study, we aimed to understand role of Niban gene, which acts as an anti-apoptotic molecule as a response to stress conditions, in adipocytes. 3T3-L1 adipocytes were treated with different doses of linoleic acid, hydrogen peroxide and ethanol; and proliferation of the cells examined with real time monitoring iCELLingence system. Gene expression levels were measured by q-PCR. As a response to 24h 480 mu M linoleic acid treatment, Niban gene expression was found to be higher than control group (p = 0.008), whereas 24 h 90 mM ethanol treatment was determined to be lower than control group (p = 0.008). The highest value of Niban gene expression among H2O2 treatment groups was detected in 4h 600 mu M H2O2 in comparison to control group (p = 0.008). To understand role of Niban in adipogenesis, Niban gene expressions were compared between pre-adipocytes and advanced fat accumulated adipocytes and determined to be significantly different (p = 0.042). Our results suggest that Niban might be involved in stress response process in adipocytes. However, the exact molecular role of Niban needs to be investigated in further studies.
Binary Particle Swarm Optimization as a Detection Tool for Influential Subsets in Linear Regression
(Taylor & Francis Ltd, 2021) Deliorman, G.; Inan, D.
An influential observation is any point that has a huge effect on the coefficients of a regression line fitting the data. The presence of such observations in the data set reduces the sensitivity and validity of the statistical analysis. In the literature there are many methods used for identifying influential observations. However, many of those methods are highly influenced by masking and swamping effects and require distributional assumptions. Especially in the presence of influential subsets most of these methods are insufficient to detect these observations. This study aims to develop a new diagnostic tool for identifying influential observations using the meta-heuristic binary particle swarm optimization algorithm. This proposed approach does not require any distributional assumptions and also not affected by masking and swamping effects as the known methods. The performance of the proposed method is analyzed via simulations and real data set applications.
Cd Dopant Effect on Structural and Optoelectronic Properties of TiO2 Solar Detectors
(Springer, 2021) Ilhan, Mustafa; Koc, Mumin Mehmet; Coskun, Burhan; Erkovan, Mustafa; Yakuphanoglu, Fahrettin
Al/n-Si/Ti1-xO2CdxO/Al photodiodes were produced using sol-gel and spin coating methods where CdO dopant was applied on different concentrations (x = 0.0; x = 0.01; x = 0.05; x = 0.10). Cd dopant effect upon structural, optical, photodiode and electrical properties was assessed. Scanning electron microscope and energy-dispersive spectra were used in the structural investigation. Optic properties were assessed using UV-Vis spectroscopy and bandgap energies of the photodiodes were calculated which were found to be between 3.25 and 3.36 eV. Increased bandgap energy was observed with increased CdO doping rate. Photodiode properties were assessed under varying daylight illuminations. Barrier height, ideality factor, dark current, linear dynamic rate, photosensitivity, photoresponsivity of the photodiodes were calculated. Electrical properties of the Al/n-Si/Ti1-xO2CdxO/Al photodiodes were calculated where conductance-voltage and capacitance-voltage plots were obtained. Corrective conductance-voltage and corrective capacitance-voltage graphs confirm that the electrical properties of the photodiodes depend on AC signal frequency. Frequency-dependent electrical characteristics were attributed to the density of interface states which were found to be between 10(11) and 10(12). Decreased density of interface state was found for increased AC signal frequency.
Differences in Occupants' Satisfaction and Perceived Productivity in High- and Low-Performance Offices
(MDPI, 2019) Gocer, Ozgur; Candido, Christhina; Thomas, Leena; Gocer, Kenan
This paper reports the results from a dataset comprising 9794 post-occupancy evaluation (POE) surveys from 77 Australian open-plan offices. This paper specifically focuses on a sub-set of 20 offices (n = 2133), identified from ranking 10 offices each, with the least (n = 1063) and highest (n = 1070) satisfaction scores, respectively. The satisfaction scores were evaluated on the basis of seven factors (i.e., building/office aesthetics and quality, thermal comfort and indoor air quality, noise distraction and privacy, personal control, connection to outdoor environment, maintenance and visual comfort, and individual space). Using the POE survey data from 20 offices, regression analyses and two-way ANOVA tests were carried out to understand the differences in occupants' satisfaction and perceived productivity arising from open-plan offices. According to the statistically significant regression analyses results, it was identified that building/office aesthetics and quality (beta = 0.55, p < 0.001) and noise distraction and privacy (beta = 0.33, p < 0.001) were the two strongest predictors contributing perceived productivity in low-performance offices. Two-way ANOVA test results for the 10 high-performance offices indicate that the perceived productivity was strongly associated with the office's physical configuration, the employees' working experience, and the working hours at that office.
Effect of Heat Treatment on Magnetic Properties of Nanocomposite Nd-Lean Nd7Fe73b20 Ribbons
(Springer, 2021) Caglar, Seyit; Kilicaslan, M. Fatih; Atasoy, Ahmet; Tiryaki, Hasan; Erkovan, Mustafa; Hong, Soon-jik
In this work, we explored the effect of heat treatment on high boron and Nd-lean content magnetic Nd7Fe73B20 nanocomposite materials via vibration sample magnetometer (VSM), X-ray diffraction, differential thermal analysis (DTA), and scanning electron microscope (SEM). The Scherer formula was employed to estimate the effect in the crystal size of the heat treatment on high boron and Nd-lean content magnetic Nd7Fe73B20 nanocomposite materials. We heat-treated samples in different conditions to obtain optimum magnetic properties. Our high-throughput fabrication strategy allows us to elucidate the possibility of obtaining Nd-lean nanocomposite NdFeB magnet in terms of the melt-spinning. We evaluated the influence of heat treatment on the Nd-lean NdFeB/alpha-Fe nanocomposite magnets produced by melt-spinning. Here, in the heat-treated ribbon at 750 degrees C for 30 min, we obtained a combination of coercivity of 450 Oe, a high-saturation magnetization of 232 emu/g in the heat-treated ribbon at 650 degrees C for 30 min, which surpasses most traditional nanocrystalline magnets based on Fe-Co and pricey. The results we present here are expected to serve as a guideline for designing new magnets for industrial applications.
The Effects of Transportation Modes on Campus Use: A Case Study of a Suburban Campus
(Elsevier Science Bv, 2019) Gocer, Ozgur; Gocer, Kenan
Efficacy of Organizational Learning and Social Capital in Online Communities of Practice: Dualities and Intersections
(IGI Global, 2017) Gürsoy S.; Yücelen M.
This chapter deals with the evolution of communities of practice by considering two key components which facilitate knowledge sharing: Organizational Learning and Social Capital. Dualities and intersections between the building blocks of these two components are investigated by discussing organizational learning in its explorative and exploitative forms, while considering social capital in its bridging and bonding forms. As a critical contemporary step of evolution, information and communication technologies are also elaborated in order to examine the impact of constant and instant tools on these facilitators of knowledge sharing. The study aims to derive proxies among these components of organizational learning and social capital in order to design an integrated framework that reflects the nature of online communities of practice. © 2018, IGI Global. All rights reserved.
Efficient Shared Path Protection Routing for Survivable Optical WDM Networks
(Institute of Electrical and Electronics Engineers Inc., 2019) Erkan, O.F.; Erkan, O.
Sustainability of the service continuity provided in the optical wavelength division multiplexing (WDM) networks with dynamic traffic environment requires effective protection schemes in the connections. Various approaches have been introduced for path protection and wavelength assignment to ensure survivability in WDM networks. In this paper, we propose a two-step algorithm to designate dedicated-path and shared-path protection schemes. The heuristic-based algorithm utilizes a global labeling which considers service time and line protection information. Thus, the algorithm aims to increase resource utilization by improving the efficiency of shared path protection. The proposed algorithm is applied to USNET and EuropeNet networks and performance analysis in terms of blocking probability and resource utilization is carried out. © 2019 IEEE.
Enforcement of the Anti-Racism Legislation of the European Union Against Antigypsyism
(Routledge Journals, Taylor & Francis Ltd, 2019) Sayan, Pinar
The European Union (EU) became a pioneer of the promotion of human rights and democratic values especially during the last decades. However, the members of the EU are not immune from the human rights violations including the areas of "equality" and "non-discrimination" that are related to racism, discrimination and xenophobia. "Antigypsyism", a form of racism, is among the most challenging human rights areas for the member states despite all recent initiatives. In this research, the use of EU competences to combat antigypsyism is analysed with case studies. It is argued that the use of the competences is limited.
Introduction of a Spatio-Temporal Mapping Based POE Method for Outdoor Spaces: Suburban University Campus as a Case Study
(Pergamon-Elsevier Science Ltd, 2018) Gocer, Ozgur; Gocer, Kenan; Basol, Altug M.; Kirac, M. Furkan; Ozbil, Ayse; Bakovic, Mujesira; Ozcan, Baris
Outdoor spaces are important to sustainable cities because they establish a common identity for social life by improving quality of urban living. The relation between outdoor spaces and building groups, competency, use period, and interaction of micro-climatic factors are needed to be investigated from a holistic approach. Unfortunately, the limited and narrow scoped POE studies on outdoor spaces make an overall assessment without causality relation. Other existing studies in outdoor spaces are mostly grouped under the headings such as; user satisfaction, space syntax and behavioral mapping, and biometeorological assessments. The intention of this paper is to introduce a new post-occupancy evaluation (POE) method integrates these studies focusing on various problems in outdoor spaces using spatio-temporal mapping. The comprehensive methodology applied in this research attempted to overcome some of the shortcomings of related studies by conducting a longitudinal study (during a year, as opposed to a few days) and also by objectively analyzing the associations of user behavior and physical attributes as well as the configurational properties of the campus layout. With this method, outdoor spaces can be evaluated in the context of the interaction between the physical environment and its users' behavior and activities, level of satisfaction and perceptions of comfort. The method has been applied on a suburban university campus in Istanbul, Turkey. The main courtyard of the campus has been subjected for map creation and result discussions.
Mediterranean Diet Adherence in Emerging Adults in Izmir
(Emerald Group Publishing Ltd, 2019) Genc, Mahmut; Genc, Seda
Purpose The purpose of this paper is to evaluate the adherence and abandonment of the Turkish emerging adults in an Izmir University located at western Mediterranean coast of Turkey and to assess potential associations with anthropometric characteristics. Design/methodology/approach A cross-sectional survey (n=494, 18-27 years) carried out in 2017 among emerging adults in University. KIDMED Index was used to assess the degree of adherence Mediterranean Diet (MedDiet). The associations of KIDMED scores with demographic, residency and anthropometric were separately reported. The data were collected through standardized questionnaires directly from participants. Findings The average KIDMED score was calculated 4.862.5. Optimum adherence to the MedDiet was found only in 13.0 percent of participants, whereas 32.6 percent had poor adherence levels. Considering self-reported anthropometric data, the BMI values of the population was calculated as 22.3 +/- 3.9kg/m(2). In population, 13.9 percent of the subjects were underweight, while 16.0 percent were overweight and 3.9 percent obese. A significant association was found between BMI and KIDMED scores both in genders and residency. Originality/value This is the first study reporting the level of adherence to the MedDiet among Turkish emerging adults in terms of residency during education and the first KIDMED study conducted in Izmir located at Aegean Sea. The results support previously proposed transition concept by several scholar from different Mediterranean countries: it was found that only 13 percent of young adults having desired dietary habits in an Aegean city with local traditional cuisine highly affected by Cretan cuisine. These results are significant for University managements and health authorities in order to take actions for returning this transition contrariwise beginning with these groups.
Pedestrian Tracking in Outdoor Spaces of a Suburban University Campus for the Investigation of Occupancy Patterns
(Elsevier, 2019) Gocer, Ozgur; Gocer, Kenan; Ozcan, Baris; Bakovic, Mujesira; Kirac, M. Furkan
The design of a livable and comfortable environment has been one of the main aims of sustainable university campus design. The creation of outdoor spaces for accommodating amenities has a positive effect on users with regard to various physiological and psychological aspects. Knowing how daily activity patterns and pedestrian movements are distributed across space is important for assessing whether or not human use and design plans are in fact successful. The aim of this study is to determine occupancy patterns and pedestrian routes in outdoor spaces during different seasons at a sustainable university campus by using spatial statistical analyses that involve ANN, MC and SDE. To perform these analyses, the researchers attempted to use a pedestrian tracking method from camera surveillance to aggregate the required data by conducing a longitudinal study. The data that were aggregated by pedestrian tracking was visualized with the use of a spatio-temporal mapping method in GIS. Logistic GWR was performed to seek the relationship between occupancy pattern (clustered distribution) and design layout of open spaces, comprising the variables of proximity to the attraction centers/entrances, and visual integration. The results confirmed that occupants prefer to use the areas that have high visual integration value and are close to attraction centers.
Persistent Othering in Turkish Cinema: The Stereotyped and Gendered Greek Identity
(Routledge Journals, Taylor & Francis Ltd, 2019) Yilmazok, Levent
In Turkish cinema, the regular narrative of exclusion or othering of minority ethnic, religious, and gender identities harnesses the nation-building process against groups that function as the 'constitutive outsider.' Although recent Turkish cinema has challenged many established cultural patterns, this challenge does not yet extend to stereotyped and heavily gendered constructions of Greek identity. In this paper, I argue that these constructions are persistent, and can be seen in recent films. Specifically, I demonstrate that Greek characters are limited to a few stereotypical names and roles, assigned heavy Turkish accents, and for the most part, confined to female roles depicted primarily as 'indecent' and/or objects of the male gaze.
Production and Marketing Structure of Large Scale Forestry Products Industry Enterprises in Turkey
(2011) Aksu, B.; Hüseyin Koç, K.; Kurtoǧlu, A.
In Turkey, a country with 21.2 million ha of forest land, it is evident that the processed forest products have not been able to be developed to realize their potential with regards to the exports possibilities. It is obvious that the situation is to the disadvantage of Turkey in terms of the trading equilibrium when the exports and imports figures are examined. According to the results of the research carried out locally with respect to the Turkish Forest Products Industry, the emphasized problems emerge as the misapplication of incentives, the disability to catch up with the technological innovations, problems regarding raw material quality, undercapitalization, lack of qualified personnel, etc. By the help of this study which had been planned to cover the whole Turkish Forest Products Industry; the target is to reveal the structural situations of the large scale businesses in Turkey in the first few years of the 20th century, where modern management principles are assumed to be applied. The research had been finalized with the comments made upon the results of the questionnaires gathered through mostly faceto-face interviews with 415 large scale forest product firms where it was assumed that contemporary management principles and technological developments were applied relatively easier. As the questionnaire study was applied by the researchers themselves directly, it was also supported through observations. © 2011 Academic Journals.
Rapid First-Stage Tests of On-Ship Infection
(Springer Heidelberg, 2017) Jerome, Carlos; Howard, Lawrence A.; Uzel, Ezgi; Androulidakis, Jameela R.
Protection against on-ship infectious disease-whether due to mishap or to harmful purpose-faces special situational problems. Sometimes, when infection levels on board have reached threshold levels, emergency actions are required. Often, the most thorough strategies for responding to threat are not feasible. A rapid first-stage test (RFT) is a fast, minimally invasive procedure used to rule out from possible infection a large percentage of an infection-threatened group. Prevention and control of on-ship infection need to combine various interconnected tactics. When timely criterion tests are not possible, the medical team must adopt fast alternative measures. The methods used to summarize protection against on-ship infectious agents included a scientific literature review and a web search. The fields of the review were maritime, health, and technology sources. Special attention was paid to material dealing with risks and threats of on-ship penetration by infectious agents, on-ship infection prevalence thresholds, and rapid diagnostic screens. The Bayes rule and the law of large numbers were applied to the analysis, for large on-ship populations, of RFT indications of crossing of an infection prevalence threshold. The increasing risk of serious on-ship infection-either accidental or purposeful-calls for a multi-layered protection approach. RFTs are a key part of the outer layer of such a defense. Well-designed and well-administered RFTs provide several advantages for defense against on-ship infection: low-cost, non-invasive, fast, and focuses on a drastically smaller number of infection possibilities.
Teneke Mahallesi in the Late Ottoman Capital: A Socio-Spatial Ground for the Co-Inhabitation of Roma Immigrants and the Local Poor
(Liverpool Univ Press, 2018) Yilgur, Egemen
The term teneke mahalle, literally "tin can neighbourhood," has been widely used since the Russo-Turkish War of 1877-1878 to describe a specific kind of urban fabrication, possibly poor and physically dilapidated, but also the sole, cheapest, and undoubtedly creative solution for the urgent housing needs of the poorest segments of the urban population. Even though these neighbourhoods were initially built at least partly by Muslim refugees, the Roma Mohadjirs,(1) teneke mahalles also welcomed other poor members of society seeking informal, easily accessible, and safe housing in late Ottoman Istanbul. This study discusses the role of the Roma in the formation of teneke mahalles, and the socio-historical dynamics that directed the non-Roma poor to co-inhabitation with Roma in these teneke mahalles, and outlines their socio-economic and cultural profile from various respects on the basis of the two oldest examples of this socio-spatial and perceptual phenomenon in Istanbul.
Understanding the Role of Urban Form in Explaining Transportation and Recreational Walking Among Children in a Logistic Gwr Model: A Spatial Analysis in Istanbul, Turkey
(Elsevier Sci Ltd, 2020) Torun, Ayse Ozbil; Gocer, Kenan; Yesiltepe, Demet; Argin, Gorsev
This study aims to examine associations between urban form factors generally, and street network configuration in particular, and walking for different purposes among children in Istanbul, Turkey. Parents of randomly selected students (ages 12-16) at 20 middle schools (N = 917) completed questionnaires about their socio-economic characteristics and the frequency of their children's walking for recreational and for transportation purposes in their neighbourhood during a typical day. The environment around 400 m of participants' homes was evaluated through GIS-based parcel-level land-use data and segment-based street connectivity measures calculated using space syntax techniques. Logistic geographically weighted regression models were estimated to measure the desired associations while adjusting for socio-economic characteristics. Results demonstrate a marginal association between urban form measures and walking behaviour but only in certain peripheral parts of the city. More importantly, increased directional accessibility, which identifies the extent to which more street length is accessible within few direction changes, is associated with higher odds of recreational walking in particular areas where a strong differentiation between scales of street connectivity structure is evident such as a supergrid of primary roads with inserted organic local streets. In addition, children residing in neighbourhoods with reduced residential density and increased commercial and recreational activities are more likely to walk for transportation purposes. The findings of this study demonstrate that the one-size-fits-all approach may not effectively encourage walking. Urban areas tend to have varying qualities that need to be handled uniquely, and therefore targeted rather than blanket interventions regarding the design of neighbourhoods around schools and homes may be beneficial in supporting walking behaviour of children.
Wear Performance of Ductile Iron After Electrolytic Plasma Hardening
(Redakcia Kovove Materialy, 2019) Ayday, A.; Durman, M.
This study aimed to improve the tribological behavior of electrolytic plasma treated (EPT) ductile iron (DI). For this purpose, ductile iron was electrolytic plasma hardened under different processing parameters (treatment time and thermal cycle). Three different types of specimens were tested: untreated DI, electrolytic plasma hardened DI and remelted DI by two type wear test. It was found that remelted DI performed much better concerning wear resistance than the other samples. The microstructure of the hardened specimens was investigated using optical microscopy. Microhardness profiles and surface hardness were investigated via the Rockwell test. The microstructure and hardness of the EPT hardened layer were dependent on the processing parameters, with the hardness values reaching the range 880-1080 +/- 10 HV0.2.
What Drives Non-Performing Loans? Evidence from Emerging and Advanced Economies During Pre- and Post-Global Financial Crisis
(Routledge Journals, Taylor & Francis Ltd, 2019) Kuzucu, Narman; Kuzucu, Serpil
We examine the determinants of non-performing loans (NPLs) in emerging countries compared to advanced countries during pre- and post-global financial crisis using dynamic panel estimation techniques. We analyze the effects of banking sector-specific factors and macroeconomic factors on NPLs utilizing a panel data set of emerging and advanced countries. Our results suggest that real GDP growth is the main determinant that affects the NPL ratio, and NPLs exhibit high persistence in emerging and advanced economies both for the pre- and post-crisis periods. We find that exchange rate and foreign direct investments (FDI) become statistically significant for emerging countries after the crisis period.
White-Matter Changes in Early and Late Stages of Mild Cognitive Impairment
(Elsevier Science Ltd, 2020) Femir-Gurtuna, Banu; Kurt, Elif; Ulasoglu-Yildiz, Cigdem; Bayram, Ali; Yildirim, Elif; Soncu-Buyukiscan, Ezgi; Bilgic, Basar
Mild Cognitive Impairment (MCI) is characterized by cognitive deficits that exceed age-related decline, but not interfering with daily living activities. Amnestic type of the disorder (aMCI) is known to have a high risk to progress to Alzheimer's Disease (AD), the most common type of dementia. Identification of very early structural changes in the brain related to the cognitive decline in MCI patients would further contribute to the understanding of the dementias. In the current study, we target to investigate whether the white-matter changes are related to structural changes, as well as the cognitive performance of MCI patients. Forty-nine MCI patients were classified as Early MCI (E-MCI, n = 24) and Late MCI (L-MCI, n = 25) due to their performance on The Free and Cued Selective Reminding Test (FCSRT). Age-Related White-Matter Changes (ARWMC) scale was used to evaluate the white-matter changes in the brain. Volumes of specific brain regions were calculated with the FreeSurfer program. Both group and correlation analyses were conducted to show if there was any association between white-matter hyperintensities (WMHs) and structural changes and cognitive performance. Our results indicate that, L-MCI patients had significantly more WMHs not in all but only in the frontal regions compared to E-MCI patients. Besides, ARWMC scores were not correlated with total hippocampal and white-matter volumes. It can be concluded that WMHs play an important role in MCI and cognitive functions are affected by white-matter changes of MCI patients, especially in the frontal regions. (C) 2020 Elsevier Ltd. All rights reserved.

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