Araştırma Çıktıları | WoS | Scopus | TR-Dizin | PubMed
Permanent URI for this communityhttps://hdl.handle.net/20.500.14719/1741
Browse
1338 results
Search Results
Publication Open Access Fluorine determination in human and animal bones by particle-induced gamma-ray emission(Springer Verlag, 2001) Sastri, Chaturvedula S.; Lyengar, Venkatesh; Blondiaux, Gilbert B.; Tessier, Yves; Petri, Hermann; Hoffmann, Peter S.; Aras, Namık K.; Zaichick, Vladimir Ye; Ortner, Hugo Manfred; Sastri, Chaturvedula S., Fachbereich Material- und Geowissenschaften, Technische Universität Darmstadt, Darmstadt, Germany; Lyengar, Venkatesh, International Atomic Energy Agency, Vienna, Vienna, Austria; Blondiaux, Gilbert B., Centre de Recherches Internationales Sciences Po, Paris, France; Tessier, Yves, Centre de Recherches Internationales Sciences Po, Paris, France; Petri, Hermann, Forschungszentrum Jülich GmbH, Julich, Germany; Hoffmann, Peter S., Fachbereich Material- und Geowissenschaften, Technische Universität Darmstadt, Darmstadt, Germany; Aras, Namik K., Department of Chemistry, Middle East Technical University (METU), Ankara, Turkey, Bahçeşehir Üniversitesi, Istanbul, Turkey; Zaichick, Vladimir Ye, A. Tsyb Medical Radiological Research Center, Obninsk, Russian Federation; Ortner, Hugo Manfred, Fachbereich Material- und Geowissenschaften, Technische Universität Darmstadt, Darmstadt, GermanyFluorine was determined in the iliac crest bones of patients and in ribs collected from post-mortem investigations by particle-induced gamma-ray emission based on the 19F(p,p′y)19F reaction, using 2.0/2.5 MeV protons. The results indicate that for 68% of the human samples the F concentration is in the range 500-1999 μg g-1. For comparison purposes fluorine was also determined in some animal bones, in some animal tissues lateral profiles of fluorine were measured. © Springer-Verlag 2001. © 2020 Elsevier B.V., All rights reserved.Publication Open Access Global variations in peak bone mass as studied by dual-energy X-ray absorptiometry(Akademiai Kiado Rt., 2004) McCloskey, Eugene V.; Dey, Abhijit; Parr, Robert M.; Aras, Namik K.; Balogh, Ádám; Bostock, J.; Borelli, Aurélio; Krishnan, Sivarama S.; Lobo, Gerald J.; Qin, Linlin; McCloskey, Eugene V., Who Collaborating Centre for Metabolic Bone Diseases, Sheffield, United Kingdom; Dey, Abhijit, Who Collaborating Centre for Metabolic Bone Diseases, Sheffield, United Kingdom; Parr, Robert M., International Atomic Energy Agency, Vienna, Vienna, Austria; Aras, Namik K., Bahçeşehir Üniversitesi, Istanbul, Turkey; Balogh, Ádám, Debreceni Egyetem, Debrecen, Hungary; Bostock, J., Who Collaborating Centre for Metabolic Bone Diseases, Sheffield, United Kingdom; Borelli, Aurélio, Hospital das Clinicas, Sao Paulo, Brazil; Krishnan, Sivarama S., Toronto General Hospital, Toronto, Canada; Lobo, Gerald J., Clínica Indisa, Santiago, Chile; Qin, Linlin, China-Japan Friendship Hospital, Beijing, ChinaIn 1994, the International Atomic Energy Agency (IAEA) initiated a 5-year Co-ordinated Research Project (CRP) to determine geographical and racial differences in peak bone mineral density (BMD) in men and women aged 15-49 years. The study demonstrates that there are distinct global differences in BMD at the hip and spine in both men and women approximating to one population standard deviation between populations with the highest and lowest BMD. These differences persist following adjustments for age, sex and body size. Such information is valuable in understanding the reasons for global differences in fracture rate and predicting future trends in fracture incidence. © 2025 Elsevier B.V., All rights reserved.Publication Open Access Precision of a dual energy X-ray absorptiometry device(Akademiai Kiado Rt., 2004) Korkusuz, Feza; Işikh, S.; Akin, Sabire; Ungan, Mehmet; Şenköylü, Alpaslan; Aras, Namik K.; Korkusuz, Feza, Medical Center, Middle East Technical University (METU), Ankara, Turkey; Işikh, S., Medical Center, Middle East Technical University (METU), Ankara, Turkey; Akin, Sabire, Medical Center, Middle East Technical University (METU), Ankara, Turkey; Ungan, Mehmet, Medical Center, Middle East Technical University (METU), Ankara, Turkey; Şenköylü, Alpaslan, Medical Center, Middle East Technical University (METU), Ankara, Turkey; Aras, Namik K., Bahçeşehir Üniversitesi, Istanbul, TurkeyThe standard method to diagnose and follow-up osteoporosis is the measurement of bone mineral density (BMD) using dual X-ray absorptiometry (DEXA). Manufacturers' manuals of DEXA devices state the intrascanner coefficient of variance is less than 0.01 g/cm2. The aim of this study was to evaluate the in vivo coefficient of variance of a Lunar DPX scanner in male and female healthy adult subjects. Average BMD for females and males were 1.170±0.091 g/cm2 and 1.272±0.115 g/cm 2, respectively. Monthly phantom measurements provided and controlled by the manufacturer were 1.243±0.008 g/cm2 (range 1.222 to 1.257) and the coefficient of variance was 0.006. It is concluded that the in vivo coefficient of variance of DEXA devices can slightly be higher than that proposed by the manufacturer. © 2025 Elsevier B.V., All rights reserved.Publication Open Access Relationship between general and context-specific attachment orientations in a Turkish sample(2006) İmamoǧlu, Selen; Olcay İmamoğlu, E.; Imamoǧlu, Selen, Faculty of Communication, Bahçeşehir Üniversitesi, Istanbul, Turkey; Olcay Imamoĝlu, E., Department of Psychology, Middle East Technical University (METU), Ankara, TurkeyThe authors explored the relationship between general and context-specific attachment orientations involving family, peer, and romantic contexts. Participants were 110 Turkish university students (50 men, 60 women). The authors used the Turkish form of K. Bartholomew and L. M. Horowitz's (1991) Relationship Questionnaire (RQ) to measure participants' general and specific attachment orientations. Using 5-point Likert-type scales, participants specified the degree to which each of the 4 descriptions of RQ (i.e., of secure, preoccupied, dismissing, and fearful orientations) represented (a) how they generally felt in close relationships, and then how they felt in their (b) family relationships, (c) romantic relationships, and (d) peer relationships. The present results indicated that participants who were generally high rather than low on a particular attachment orientation tended to be so across the 3 contexts, thereby supporting the trait-like conceptualization of attachment styles. However, the present results also supported conceptualization of attachment orientations as specific context-related tendencies because regardless of their general orientations, participants reported feeling relatively more secure in some relationships (e.g., family) than in others (e.g., romantic). The authors discussed the present results as supporting (a) the coexistence of both general and specific attachment orientations in the cognitive system and (b) the cross-cultural validity of attachment orientations. Copyright © 2006 Heldref Publications. © 2009 Elsevier B.V., All rights reserved., MEDLINE® is the source for the MeSH terms of this document.Publication Metadata only Prediction of cyclosporine A blood levels: An application of the adaptive-network-based fuzzy inference system (ANFIS) in assisting drug therapy(2008) Gören, Sezer; Karahoca, Adem; Onat, Filiz Yilmaz; Gören, Mehmet Zafer; Gören, Sezer, Department of Computer Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Karahoca, Adem, Department of Computer Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Onat, Filiz Yilmaz, Department of Pharmacology and Clinical Pharmacology, Marmara Üniversitesi Tip Fakültesi, Istanbul, Turkey; Gören, Mehmet Zafer, Department of Pharmacology and Clinical Pharmacology, Marmara Üniversitesi Tip Fakültesi, Istanbul, TurkeyObjective: Therapeutic drug monitoring (TDM) is a procedure in which the levels of drugs are assayed in various body fluids with the aim of individualizing the dose of critical drugs, such as cyclosporine A. Cyclosporine A assays are performed in blood. Methods: We proposed the use of the Takagi and Sugeno-type adaptive-network-based fuzzy inference system (ANFIS) to predict the concentration of cyclosporine A in blood samples taken from renal transplantation patients. We implemented the ANFIS model using TDM data collected from 138 patients and 20 input parameters. Input parameters for the model consisted of concurrent use of drugs, blood levels, sampling time, age, gender, and dosing intervals. Results: Fuzzy modeling produced eight rules. The developed ANFIS model exhibited a root mean square error (RMSE) of 0.045 with respect to the training data and an error of 0.057 with respect to the checking data in the MATLAB environment. Conclusion: ANFIS can effectively assist physicians in choosing best therapeutic drug dose in the clinical setting. © 2008 Springer-Verlag. © 2009 Elsevier B.V., All rights reserved., MEDLINE® is the source for the MeSH terms of this document.Publication Open Access Organizational commitment of military physicians(Association of Military Surgeons of the US [email protected], 2009) Demir, Cesim; Şahin, Bayram; Tekef, Kadir; Uçar, Muharrem; Kurşun, Olcay; Demir, Cesim, Gülhane Eğitim ve Araştırma Hastanesi, Ankara, Turkey; Şahin, Bayram, Department of Health Care Management, Hacettepe Üniversitesi, Ankara, Turkey; Tekef, Kadir, Gülhane Eğitim ve Araştırma Hastanesi, Ankara, Turkey; Uçar, Muharrem, Department of Medical History and Deontology, Gülhane Eğitim ve Araştırma Hastanesi, Ankara, Turkey; Kursun, Olcay, Department of Computer Engineering, Bahçeşehir Üniversitesi, Istanbul, TurkeyAn individual's loyalty or bond to his or her employing organization, referred to as organizational commitment, influences various organizational outcomes such as employee motivation, job satisfaction, performance, accomplishment of organizational goals, employee turnover, and absenteeism. Therefore, as in other sectors, employee commitment is crucial also in the healthcare market. This study investigates the effects of organizational factors and personal characteristics on organizational commitment of military physicians using structural equation modeling (SEM) on a self-report, cross-sectional survey that consisted of 635 physicians working in the 2 biggest military hospitals in Turkey. The results of this study indicate that professional commitment and organizational incentives contribute positively to organizational commitment, whereas conflict with organizational goals makes a significantly negative contribution to it. These results might help develop strategies to increase employee commitment, especially in healthcare organizations, because jobrelated factors have been found to possess greater impact on organizational commitment than personal characteristics. Reprint and Copyright © by Association of Military Surgeons of U.S., 2009. © 2017 Elsevier B.V., All rights reserved.Publication Metadata only Caregiving style, problem solving strategies, anger style and health status in women caregivers of alzheimer patients and healthy elderly, Alzhei̇mer hastalarina ve saǧlikli yaşlilara bakimveren kadin yakinlarda bakim verme tarzi, problem çözme strateji̇leri̇,öfke tarzlari ve saǧlik durumunun i̇ncelenmeṡi(2009) Korkut, Yeflim; Sertel-Berk, Hanife Özlem; Korkut, Yeflim, Bahçeşehir Üniversitesi, Istanbul, Turkey; Sertel-Berk, Hanife Özlem, Psikoloji Anabilim Dali, Istanbul Üniversitesi, Istanbul, TurkeyIntroduction: The principle aim of this study is to investigate the caregiving style of the participants and the kind of support they receive, to compare anger levels, problem solving approaches and health problems of Alzheimer Disease (AD) patient female caregivers with a control group. This study further examines the effect of group, age, health status, anger style and problem solving style on depression. Materials and Method: 42 female caregivers (22 AD and 20 control) participated in the study. They were given a demographic questionnaire, Beck Depression Inventory-BDI, State-Trait Anger Scale-STAS and Problem Solving Inventory-PSI. Results: Results indicated that both AD and control group caregivers were similar in terms of caregiving style. Though AD and control group caregivers did not differ in terms PSI and BDI, there were significant differences between those who reported illness and those who did not in terms of impatient and thoughtful approach sub-tests of PSI. The regression analysis showed that age and repressed anger significantly explained the variation in BDI. Conclusion: Altogether results showed that in a relatively low at risk women caregivers group, regardless of being AD caregiver or not, age and repressed anger are important factors on depression levels. Health status of caregiver seems to be a determining factor on PSI. © 2009 Elsevier B.V., All rights reserved.Publication Open Access Whole-exome sequencing identifies recessive WDR62 mutations in severe brain malformations(2010) Bilgüvar, Kaya; Öztürk, Ali Kemal; Louvi, Angeliki; Kwan, Kenneth Y.; Choi, Murim; Tatlí, Burak; Yalnizoǧlu, Dilek; Tüysüz, Beyhan; Caglayan, Ahmet Okay; Gökben, Sarenur; Bilgüvar, Kaya, Department of Neurosurgery, Yale School of Medicine, New Haven, United States, Department of Neurobiology, Yale School of Medicine, New Haven, United States, Department of Genetics, Yale School of Medicine, New Haven, United States; Öztürk, Ali Kemal, Department of Neurosurgery, Yale School of Medicine, New Haven, United States, Department of Neurobiology, Yale School of Medicine, New Haven, United States, Department of Genetics, Yale School of Medicine, New Haven, United States; Louvi, Angeliki, Department of Neurosurgery, Yale School of Medicine, New Haven, United States, Department of Neurobiology, Yale School of Medicine, New Haven, United States, Department of Genetics, Yale School of Medicine, New Haven, United States; Kwan, Kenneth Y., Department of Neurobiology, Yale School of Medicine, New Haven, United States, Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, United States; Choi, Murim, Department of Genetics, Yale School of Medicine, New Haven, United States; Tatlí, Burak, Department of Pediatrics, İstanbul Tıp Fakültesi, Istanbul, Turkey; Yalnizoǧlu, Dilek, Department of Pediatrics, Hacettepe Üniversitesi, Ankara, Turkey; Tüysüz, Beyhan, Department of Pediatrics, İstanbul University-Cerrahpaşa Cerrahpaşa Faculty of Medicine, Istanbul, Turkey; Caglayan, Ahmet Okay,; Gökben, Sarenur, Department of Pediatrics, Ege University Medical School, Izmir, TurkeyThe development of the human cerebral cortex is an orchestrated process involving the generation of neural progenitors in the periventricular germinal zones, cell proliferation characterized by symmetric and asymmetric mitoses, followed by migration of post-mitotic neurons to their final destinations in six highly ordered, functionally specialized layers1,2. An understanding of the molecular mechanisms guiding these intricate processes is in its infancy, substantially driven by the discovery of rare mutations that cause malformations of cortical development3-6. Mapping of disease loci in putative Mendelian forms of malformations of cortical development has been hindered by marked locus heterogeneity, small kindred sizes and diagnostic classifications that may not reflect molecular pathogenesis. Here we demonstrate the use of whole-exome sequencing to overcome these obstacles by identifying recessive mutations in WD repeat domain 62 (WDR62) as the cause of a wide spectrum of severe cerebral cortical malformations including microcephaly, pachygyria with cortical thickening as well as hypoplasia of the corpus callosum. Some patients with mutations in WDR62 had evidence of additional abnormalities including lissencephaly, schizencephaly, polymicrogyria and, in one instance, cerebellar hypoplasia, all traits traditionally regarded as distinct entities. In mice and humans, WDR62 transcripts and protein are enriched in neural progenitors within the ventricular and subventricular zones. Expression of WDR62 in the neocortex is transient, spanning the period of embryonic neurogenesis. Unlike other known microcephaly genes, WDR62 does not apparently associate with centrosomes and is predominantly nuclear in localization. These findings unify previously disparate aspects of cerebral cortical development and highlight the use of whole-exome sequencing to identify disease loci in settings in which traditional methods have proved challenging. © 2010 Macmillan Publishers Limited. All rights reserved. © 2012 Elsevier B.V., All rights reserved., MEDLINE® is the source for the MeSH terms of this document.Publication Metadata only Coupled nonparametric shape and moment-based intershape pose priors for multiple basal ganglia structure segmentation(2010) Uzunbaş, Mustafa Gökhan; Soldea, Octavian; Ünay, Devrim; Çetin, Müjdat; Unal, Gozde Bozkurt; Erçil, Aytül; Ekin, Ahmet; Uzunbaş, Mustafa Gökhan, Faculty of Engineering and Natural Sciences, Sabancı Üniversitesi, Tuzla, Turkey, Department of Computer Science, Piscataway, United States; Soldea, Octavian, Faculty of Engineering and Natural Sciences, Sabancı Üniversitesi, Tuzla, Turkey; Ünay, Devrim, Department of Electrical and Electronic Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Çetin, Müjdat, Faculty of Engineering and Natural Sciences, Sabancı Üniversitesi, Tuzla, Turkey; Unal, Gozde Bozkurt, Faculty of Engineering and Natural Sciences, Sabancı Üniversitesi, Tuzla, Turkey; Erçil, Aytül, Faculty of Engineering and Natural Sciences, Sabancı Üniversitesi, Tuzla, Turkey; Ekin, Ahmet, Video Processing and Analysis Group, Philips Research, Eindhoven, NetherlandsThis paper presents a new active contour-based, statistical method for simultaneous volumetric segmentation of multiple subcortical structures in the brain. In biological tissues, such as the human brain, neighboring structures exhibit co-dependencies which can aid in segmentation, if properly analyzed and modeled. Motivated by this observation, we formulate the segmentation problem as a maximum a posteriori estimation problem, in which we incorporate statistical prior models on the shapes and intershape (relative) poses of the structures of interest. This provides a principled mechanism to bring high level information about the shapes and the relationships of anatomical structures into the segmentation problem. For learning the prior densities we use a nonparametric multivariate kernel density estimation framework. We combine these priors with data in a variational framework and develop an active contour-based iterative segmentation algorithm. We test our method on the problem of volumetric segmentation of basal ganglia structures in magnetic resonance images. We present a set of 2-D and 3-D experiments as well as a quantitative performance analysis. In addition, we perform a comparison to several existent segmentation methods and demonstrate the improvements provided by our approach in terms of segmentation accuracy. © 2010 IEEE. © 2010 Elsevier B.V., All rights reserved.Publication Metadata only The impact of conservative discourses in family policies, population politics, and gender rights in Poland and Turkey(2011) Korkut, Umut; Eslen-Ziya, Hande; Korkut, Umut, Glasgow Business School, Glasgow Caledonian University, Glasgow, United Kingdom; Eslen-Ziya, Hande, Bahçeşehir Üniversitesi, Istanbul, TurkeyThis article uses childcare as a case study to test the impact of ideas that embody a traditional understanding of gender relations in relation to childcare. Conservative ideas regard increasing female labor market participation as a cause of decreasing fertility on the functioning of a set of general policies to increase fertility rates. It looks into the Polish and Turkish contexts for empirical evidence. The Polish context shows a highly institutionalized system of family policies in contrast to almost unessential institutions in Turkey. Formally, the labor market participation of women is much lower in Turkey than in Poland. Yet, given the size of the informal market in Turkey, womens labor participation is obviously higher than what appears in the statistics. Bearing in mind this divergence, the article suggests Poland and Turkey as two typologies for studying population politics in contexts where socially conservative ideas regarding gender remain paramount. We qualify ideas as conservative if they enforce a traditional understanding of gender relations in care-giving and underline womens role in the labor market as an element of declining fertility. In order to delineate ideational impact, this article looks into how ideas (a) supplant and (b) substitute formal institutions. Therefore, we argue that there are two mechanisms pertaining to the dominance of conservative conventions: conservative ideas may either supplant the institutional impact on family policies, or substitute them thanks to a superior reasoning which societies assign to them. Furthermore, conservative conventions prevail alongside womens customary unpaid work as care-givers regardless of the level of their formal workforce participation. We propose as our major findings for the literature of population politics that ideas, as ubiquitous belief systems, are more powerful than institutions since they provide what is perceived as legitimate, acceptable, and good for the societies under study. In the end, irrespective of the presence of institutions, socially conservative ideas prevail. © The Author 2011. Published by Oxford University Press. All rights reserved. © 2012 Elsevier B.V., All rights reserved., MEDLINE® is the source for the MeSH terms of this document.