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Publication Open Access #COVID19 and #Breastcancer: a qualitative analysis of tweets(Multidisciplinary Digital Publishing Institute (MDPI), 2022) Naganathan, G.; Cleland, J.; Reel, E.; Cil, T.; Bilgen, İdil; School of MedicineRapid and efficient communication regarding quickly evolving medical information was paramount for healthcare providers and patients throughout the COVID-19 pandemic. Over the last several years, social media platforms such as Twitter have emerged as important tools for health promotion, virtual learning among healthcare providers, and patient support. We conducted a qualitative thematic content analysis on tweets using the hashtags #BreastSurgery, #BreastCancer, #BreastOncology, #Pandemic, and #COVID19. Advocacy organizations were the most frequent authors of tweets captured in this dataset, and most tweets came from the United States of America (64%). Seventy-three codes were generated from the data, and, through iterative, inductive analysis, three major themes were developed: patient hesitancy and vulnerability, increased efforts in knowledge sharing, and evolving best practices. We found that Twitter was an effective way to share evolving best practices, education, and collective experiences among key stakeholders. As Twitter is increasingly used as a tool for health promotion and knowledge translation, a better understanding of how key stakeholders engage with healthcare-related topics on the platform can help optimize the use of this powerful tool.Publication Open Access A case of Burkitt’s lymphoma mimicking peritonitis carcinomatosa(Galenos Yayınevi, 2020) Örnek, Serdar; Tecimer Tülay; Ferhanoğlu, Ahmet Burhan; Büyüktaş, Deram; Faculty Member; Faculty Member; School of Medicine; 18320; N/APublication Open Access A characterization of the extended serial correspondence(Elsevier, 2015) Heo, Eun Jeong; Department of Economics; Yılmaz, Özgür; Faculty Member; Department of Economics; College of Administrative Sciences and Economics; 108638We study the problem of assigning objects to a group of agents. We focus on probabilistic methods that take agents' ordinal preferences over the objects. Importantly, we allow for indifferences among objects. Katta and Sethuraman (2006) propose the extended serial correspondence to solve this problem. Our main result is a characterization of the extended serial correspondence in welfare terms by means of stochastic dominance efficiency, stochastic dominance no-envy and "limited invariance," a requirement we adapt from Heo (2014a). We also prove that an assignment matrix is selected by the extended serial correspondence if and only if it satisfies "non-wastefulness" and "ordinal fairness," which we adapt from Kesten et al.Publication Open Access A clinical comparison of home-based and hospital-based exercise programs following arthroscopic capsulolabral repair for anterior shoulder instability(Human Kinetics, 2020) Atalar, Ata Can; Eren, Şule Meral; Uçak, Ayla; Çerezci, Önder; Eren, İlker; Canbulat, Nazan; Demirhan, Mehmet; Faculty Member; Faculty Member; School of Medicine; Koç University Hospital; 168021; 58534; 9882Context: ideal rehabilitation method following arthroscopic capsulolabral repair surgery for anterior shoulder instability has not been proven yet. Although rapid or slow protocols were compared previously, home- or hospital-based protocols were not questioned before. Objective: the aim of this prospective unrandomized controlled clinical trial is to compare the clinical outcomes of home-based and hospital-based rehabilitation programs following arthroscopic Bankart repair. Design: non-randomized controlled trial. Setting: orthopedics and physical therapy units of a single institution. Patients: fifty-four patients (49 males and 5 females) with an average age of 30.5 (9.1) years, who underwent arthroscopic capsulolabral repair and met the inclusion criteria, with at least 1-year follow-up were allocated into 2 groups: home-based (n = 33) and hospital-based (n = 21) groups. Interventions: both groups received identical rehabilitation programs. Patients in the home-based group were called for follow-up every 3 weeks. Patients in the hospital-based group admitted for therapy every other day for a total of 6 to 8 weeks. Both groups were followed identically after the eighth week and the rehabilitation program continued for 6 months. Main Outcome Measures: Clinical outcomes were assessed using Disabilities of Arm Shoulder Hand, Constant, and Rowe scores. Mann-Whitney U test was used to compare the results in both groups. Wilcoxon test was used for determining the progress in each group. Results: groups were age and gender matched (P =.61, P =.69). Average number of treatment sessions was 13.8 (7.3) for patients in the hospital-based group. Preoperative Disabilities of Arm Shoulder Hand (27.46 [11.81] vs 32.53 [16.42], P =.22), Constant (58.23 [14.23] vs 54.17 [10.46], P =.13), and Rowe (51.72 [15.36] vs 43.81 [19.16], P =.12) scores were similar between groups. Postoperative scores at sixth month were significantly improved in each group (P =.001, P =.001, and P =.001). No significant difference was observed between 2 groups regarding clinical scores in any time point. Conclusions: we have, therefore, concluded that a controlled home-based exercise program is as effective as hospital-based rehabilitation following arthroscopic capsulolabral repair for anterior shoulder instability.Publication Open Access A clinical scoring system to predict the development of bronchopulmonary dysplasia(Thieme Medical Publishers, 2015) Hayran, Mutlu; Derin, Hatice; Ovalı, Fahri; N/A; Gürsoy, Tuğba; Faculty Member; School of Medicine; 214691Objective: This study aims to develop a scoring system for the prediction of bronchopulmonary dysplasia (BPD). Methods: Medical records of 652 infants whose gestational age and birth weight were below 32 weeks and 1,500g, respectively, and who survived beyond 28th postnatal day were reviewed retrospectively. Logistic regression methods were used to determine the clinical and demographic risk factors within the first 72 hours of life associated with BPD, as well as the weights of these factors on developing BPD. Predictive accuracy of the scoring system was tested prospectively at the same unit. ResultsBirth weight, gestational age, gender, presence of respiratory distress syndrome, patent ductus arteriosus, intraventricular hemorrhage, hypotension were the most important risk factors for BPD. Therefore, a scoring system (BPD-TM score) ranging from 0 to 13 and grouped in four tiers (0-3: low, 4-6: low intermediate, 7-9: high intermediate, and 10-13: high risk) was developed based on these factors. Below the score of 4, 4.1% of infants (18/436), above the score of 9, 100% (29/29) of the infants developed BPD. The score was validated successfully in 172 infants. Conclusion: With this easy to use scoring system, one can predict the neonate at risk for BPD at 72 hours of life and direct preventive measures toward these infants.Publication Open Access A combined VBM and DTI study of schizophrenia: bilateral decreased insula volume and cerebral white matter disintegrity corresponding to subinsular white matter projections unlinked to clinical symptomatology(Aves, 2017) Ulaşoğlu-Yıldız, Çiğdem; Aslan, Selçuk; Talı, Erhan Turgut; N/A; N/A; Onay, Aslıhan; Eser, Hale Yapıcı; Faculty Member; School of Medicine; N/A; 134359PURPOSE: Grey matter and white matter changes within the brain are well defined in schizophrenia. However, most studies focused on either grey matter changes or white matter integrity separately; only in limited number of studies these changes were interpreted in the same frame. In addition, the relationship of these findings with clinical variables is not clearly established. Here, we aimed to investigate the grey matter and white matter changes in schizophrenia patients and exhibit the relation of these imaging findings with clinical variables. METHODS: A total of 20 schizophrenia patients and 16 matched healthy controls underwent magnetic resonance imaging to investigate the grey matter and white matter alterations that occur in schizophrenia patients using voxel-based morphometry (VBM) and whole brain voxel-wise analysis of diffusion tensor imaging (DTI) parameters with SPM8, respectively. While the preprocessing steps ofVBM were performed with the default parameters of VBM8 toolbox, the preprocessing steps of DTI were carried out using FSL. Additionally, VBM results were correlated with clinical variables. RESULTS: Bilateral insula showed decreased grey matter volume in schizophrenia patients compared with healthy controls (P < 0.01). The opposite contrast did not show a significant difference. Psychiatric scores, duration of illness, and age were not correlated with the decreased grey matter volume of insula in schizophrenia patients. DTI analysis revealed a significant increase in mean, radial, and axial diffusivity, mainly of the fibers of bilateral anterior thalamic radiation and superior longitudinal fasciculus with left predominance, which intersected with bilateral subinsular white matter (P < 0.05). CONCLUSION: Our findings suggest that insula may be the main affected brain region in schizophrenia, which is also well supported by the literature. Our results were independent of disease duration and schizophrenia symptoms. White matter alterations were observed within bilateral anterior thalamic radiation and superior longitudinal fasciculus that intersects with subinsular white matter. Studies with larger sample sizes and more detailed clinical assessments are required to understand the function of insula in the neurobiology of schizophrenia.Publication Open Access A comparative study on GaSb epilayers grown on nominal and vicinal Si(100) substrates by molecular beam epitaxy(Institute of Physics (IOP) Publishing, 2020) Arpapay, Burcu; Suyolcu, Y. Eren; van Aken, Peter A.; Gülgün, Mehmet Ali; Serincan, Uğur; Çorapçıoğlu, Gülcan; n2STAR-Koç University Nanofabrication and Nanocharacterization Center for Scientifc and Technological Advanced ResearchThe direct growth of GaSb buffer layers on Si substrates is attracting considerable interest in the integration of group III-Sb based device structures on lower-cost Si substrates. Here, we present the effect of various growth steps on the defect types and defect density that are crucial for advancing high crystal quality GaSb buffer layer on nominal/vicinal Si substrate. As a growth step, the applied thermal annealing at an intermediate step provided a decrease in the threading dislocation (TD) density down to 1.72 x 10(8) cm(-2), indicating a more effective method compared to post-growth annealing. Additionally, the importance of period number and position of GaSb/AlSb superlattice layers inserted in GaSb epilayers is demonstrated. In the case of the GaSb epilayers grown on vicinal substrates, the APB density as low as 0.06 mu m(-1) and TD density of 1.98 x 10(8) cm(-2) were obtained for the sample grown on 4 degrees miscut Si(100) substrate.Publication Open Access A comparison of rates and severity of chronic kidney disease in deceased-donor and living-donor liver transplant recipients: times matter(TÜBİTAK, 2021) Yankol, Yücel; Bugeaud, Emily; Zens, Tiffany; Rizzari, Michael; Leverson, Glen E.; Foley, David; Mezrich, Joshua D.; D'Alessandro, Anthony M.; Acarlı, Koray S.; Fernandez, Luis A.; Mecit, Nesimi; Kanmaz, Turan; Andaçoğlu, Oya Münevver; Kalayoğlu, Münci; Faculty Member; School of Medicine; Koç University HospitalBackground/aim: the progression of chronic kidney disease (CKD) in recipients of living-donor liver transplant (LDLT) compared to deceased-donor liver transplant (DDLT) has not been studied in the literature. We hypothesize that CKD stage progression in LDLT recipients is reduced compared to that of their DDLT counterparts. Materials and methods: a retrospective study was undertaken including 999 adult, single-organ, primary liver transplant recipients (218 LDLT and 781 DDLT) at 2 centers between January 2003 and December 2012, in which CKD progression and regression were evaluated within the first 3 years after transplantation. Results: waiting time from evaluation to transplantation was significantly lower in LDLT patients compared to recipients of DDLT. CKD stage progression from preoperative transplant evaluation to transplantation was significantly greater in DDLT. Deceased-donor liver transplant recipients continued to have higher rates of clinically significant renal disease progression (from stage I-II to stage III-V) across multiple time points over the first 3 years posttransplant. Furthermore, a greater degree of CKD regression was observed in recipients of LDLT. Conclusion: it can be concluded that LDLT provides excellent graft and patient survival, significantly reducing the overall incidence of clinically significant CKD stage progression when compared to DDLT. Moreover, there is a significantly higher incidence of CKD stage regression in LDLT compared to DDLT. These observations were maintained in both high and low model for end-stage liver disease(MELD)populations. This observation likely reflects earlier access to transplantation in LDLT as one of the contributing factors to preventing CKD progression.Publication Open Access A comparison of the LVDP and {\Lambda} CDM cosmological models(Springer, 2012) Department of Physics; Akarsu, Özgür; Dereli, Tekin; Faculty Member; Department of Physics; College of Sciences; N/A; 201358We compare the cosmological kinematics obtained via our law of linearly varying deceleration parameter (LVDP) with the kinematics obtained in the Lambda CDM model. We show that the LVDP model is almost indistinguishable from the Lambda CDM model up to the near future of our universe as far as the current observations are concerned, though their predictions differ tremendously into the far future.Publication Open Access A Lower Paleolithic assemblage from western Anatolia: the lithics from Bozyer(Elsevier, 2019) Dinçer, Berkay; Çilingiroğlu, Çiler; Department of Archeology and History of Art; Roosevelt, Christopher Havemeyer; Roosevelt, Christina Marie Luke; Faculty Member; Department of Archeology and History of Art; College of Social Sciences and Humanities; N/A; 235112In 2005 the Central Lydia Archaeological Survey (CLAS) identified an open-air Lower Paleolithic site called Bozyer near Lake Marmara in the province of Manisa, Turkey. Intensive survey of Bozyer in 2008 resulted in collection of over 300 stone tools. Subsequent systematic analysis attributed 189 of these lithics to a Lower Paleolithic industry. The assemblage is characterized by flakes and retouched flake tools, many of which were produced with the bipolar flaking technique; preferential use of locally available quartz and quartzite over chert; a low proportion of cores, most of which were reused as choppers and chopping tools; and the absence of bifaces and other large cutting tools. With few exceptions, similar assemblages are rare in Anatolia, and comparable industries from Eurasia and the Near East date to the Early Pleistocene period. The lithic industry from Bozyer thus joins other nearby sites in evidencing some of the earliest hominin activities outside Africa, shedding new light on growing understandings of Lower Paleolithic technology, mobility, and activities in Anatolia.