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Publication Open Access A benevolent angel with blue eyes(Türk Kütüphaneciler Derneği, 2019) Ergün, Canan; Other; Suna Kıraç LibraryI met Professor Dr. Meral Alpay on my first day at Istanbul University, Department of Librarianship. I tried to tell my memory of this first day that I met with Professor Dr. Meral Alpay. / İstanbul Üniversitesi Kütüphanecilik Bölümünü kazanıp, okula başladığım ilk gün Prof. Dr. Meral Alpay hocam ile tanışma anımı anlatmaya çalıştım.Publication Open Access A class of Banach algebras whose duals have the Schur property(TÜBİTAK, 1999) Mustafayev, H.; Department of Mathematics; Ülger, Ali; Faculty Member; Department of Mathematics; College of SciencesCall a commutative Banach algebra A a γ-algebra if it contains a bounded group Λ such that aco(Λ) contains a multiple of the unit ball of A. In this paper, first by exhibiting several concrete examples, we show that the class of γ-algebras is quite rich. Then, for a γ-algebra A, we prove that A* has the Schur property iff the Gelfand spectrum Σ of A is scattered iff A* = ap(A) iff A* = Span(Σ).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 diagnostic challenge: risk factors and surgical treatment of laryngeal chondroradionecrosis(Aves, 2022) Başaran, Bora; Doruk, Can; Çaytemel, Berkay; Şen, Cömert; Aslan, İsmet; Ünsaler, Selin; School of Medicine; 167909Objectives: thirteen cases of laryngeal chondroradionecrosis unresponsiveto conservative treatment and treated with laryngectomy were presented with an analysis of possible risk factors. Methods: retrospective analysis of 13 patients operated on for chondroradionecrosis was made. Characteristics of the primarytumor, chondroradionecrosis grade, number of biopsies needed to rule out recurrence, and laryngectomy indications were analyzed. The possible predisposing factors such as alcohol and tobacco use and other major chronic diseases were investigated. Results: all of the patients had a history of smoking. The most common comorbidity was hypertension (46.2%), followed by chronic obstructive pulmonary disease (23.1%). The onset of symptoms was documented within the 10 monthsfollowing the radiation therapy in 12 of the patients (93.3%) and 12 years after the primary radiation therapy in 1 patient. Asthe most common symptom, fetor oris was observed in all of the patients, followed by dysphagia (69.2%), hoarseness (61.5%), pain (53.8%), dyspnea (46.2%), and necrotic fistula formation in the anterior neck (15.4%) consecutively. Tumor suspicion (84.6%) was the most common indication for laryngectomy followed by chronic aspiration or feeding disorder (61.5%). Twelve patients were treated with total and 1 with supraglottic laryngectomy. Pectoralis major muscle flap was used in all of the patients for pharyngeal reconstruction or protection against salivary fistula. Conclusion: diagnosis of chondroradionecrosis is challenging, and tumor recurrence should always be kept in mind. Patients must be informed about the possibility of chondroradionecrosis complications including laryngectomy. Introduction: chondroradionecrosis is a rare and the most severe complication of radiation therapy for laryngeal carcinoma.Publication Open Access A new risk-scoring system for colorectal cancer and polyp screening by Turkish Colorectal Cancer and Polyp Study Group(Aves, 2022) Erdem, L.; Akbal, E.; Koçak, E.; Tucer, D.; Üçbilek, E.; Uyanıkoğlu, A.; Dolapçıoğlu, C.; Şirin, G.; Alkım, H.; Soylu, A.; Doğanay, L.; Kürbüz, A.K.; Özdil, K.; Alagözlü, H.; Erürker Öztürk, T.; Sezikli, M.; Adalı, G.; Çoban, M.; Hülagü, S.; Değertekin, H.; Atasoy, A.; Akyüz, F.; Gaffarlı, İ.; Saruç, M.; Altıntaş, E.; Sezgin, O.; Tözün N.; Ahıshalı, Emel; School of MedicineBackground: colorectal cancer is one of the most commonly diagnosed types of cancer worldwide. An early diagnosis and detection of colon cancer and polyp can reduce mortality and morbidity from colorectal cancer. Even though there are a variety of options in screening tests, the question remains on which test is the most effective for the early detection of colorectal cancer. In this prospective study, we aimed to develop a simple, useful, effective, and reliable scoring system to detect colon polyp and colorectal cancer. Methods: we enrolled 6508 subjects over the age of 18 from 16 centers, with colonoscopy screening. The age, smoking status, alcohol consumption, body mass index, polyp incidence, polyp size, number and localization, and pathologic findings were recorded. Results: the age, male gender, obesity, smoking, and family history were found as independent risk factors for adenomatous polyp. We have developed a new scoring system which can be used for these factors. With a score of 4 or above, we found the following: sensitivity 81%, specificity 40%, positive predictive value 25.68%, and negative predictive value 89.84%, for adenomatous polyp detection; and sensitivity 96%, specificity 39%, positive predictive value 3.35%, negative predictive value 99.29%, for colorectal cancer detection. Conclusion: even though the first colorectal cancer screening worldwide is generally performed for individuals over 50 years of age, we recommend that screening for colorectal cancer might begin for those under 50 years of age as well. Individuals with a score ? 4 must be included in the screening tests for colorectal cancer.Publication Open Access A nonminimally coupled, conformally extended Einstein-Maxwell theory of pp-waves(TÜBİTAK, 2020) Department of Physics; Dereli, Tekin; Şenikoğlu, Yorgo; Researcher; Department of Physics; Graduate School of Sciences and Engineering; College of Sciences; 201358; N/AA nonminimal coupling of Weyl curvatures to electromagnetic fields is considered in Brans-Dicke-Maxwell theory. The gravitational field equations are formulated in a Riemannian spacetime where the spacetime torsion is constrained to zero by the method of Lagrange multipliers in the language of exterior differential forms. The significance and ramifications of nonminimal couplings to gravity are examined in a pp-wave spacetime.
Publication Metadata only A personal ethics responsibility example: the relationship between child development and drugs taken by pregnant mother(TÜBİTAK, 2008) Üstün, Çağatay; Department of International Relations; Özgürler, Özge; Undergraduate Student; Department of International Relations; College of Administrative Sciences and Economics; N/AKişisel sorumluluk önemli bir etik kavramdır. Bu durumda hamile anne birincil derecede önem arz etmektedir. Hamile anne kendisinin ve bebeğin sağlığının korumak, bebeğin normal gelişimini temin etmek için bazı şeylere dikkat etmelidir. Bu anlamda ilaçların hamile annenin bebeği üzerindeki genel etkilerine değineceğiz. Böylece annelerin kişisel etik sorumluluğunu vurgulamayı hedefliyoruz.Publication Metadata only A possibly fatal outcome of oral contraceptive therapy: estrogen triggered hereditary angioedema attack in an adolescent(Galenos Yayınevi, 2021) Demirkol, Demet; Birben, Esra; Soyer, Özge; N/A; Balkancı, Uğur Berkay; Yeşiltepe Mutlu, Rahime Gül; Yılmaz, Özlem; Saçkesen, Cansın; Undergraduate Student; Faculty Member; Doctor; Faculty Member; School of Medicine; School of Medicine; N/A; School of Medicine; Koç University Hospital; Koc University Hospital; N/A; 153511; 140706; 182537Hereditary angioedema (HAE) is characterized by recurrent angioedema attacks with no urticaria. This disease has a high mortality due to asphyxia. Level of complement 4 (C4), C1 esterase inhibitor (C1-INH) level and function, and genetic mutations determine different endotypes of HAE. Clinical presentation and the triggers of vasogenic edema may change according to the endotypes. An adolescent girl with oligomenorrhea, obesity, hirsutism, and acanthosis nigricans was diagnosed with polycystic ovary syndrome (PCOS) and prescribed ethinyl estradiol & cyproterone acetate containing oral contraceptive (OC). On the 16th day of treatment, she developed angioedema on the face, neck, and chest leading to dyspnea. Adrenaline, antihistamine, and corticosteroid treatments were ineffective. In the family history, the patient's mother and two cousins had angioedema attacks. C1-INH concentrate was administered with a diagnosis of HAE. C4, and C1-INH level and activity were normal. Genetic analysis identified a mutation of Factor XII (F12) gene, and the diagnosis of Factor 12 (F12)-related HAE was made. OC treatment discontinued. She has had no additional angioedema attacks in the follow-up period of two years. OC containing estrogen may induce the life-threatening first attack of F12-related HAE even in children. Recurring angioedema attacks in the family should be asked before prescribing estrogen-containing OC pills.Publication Open Access A practitioner’s guide to handling irregularities resulting from the 2014 revisions of the Turkish Household Labor Force Survey(Boğaziçi Üniversitesi İktisadi ve İdari Bilimler Fakültesi, 2021) Poyraz, Meltem; Department of Economics; Demirci, Murat; Faculty Member; Department of Economics; College of Administrative Sciences and Economics; 272082We document the implications of the 2014 revisions to the Turkish Household Labor Force Survey and offer guidance on how to handle the irregularities in population and unemployment statistics that resulted from two particular revisions. First, new population projections were adopted to assign survey weights. Second, a narrower definition of unemployment was adopted. We propose methods to adjust the survey weights for the pre-2014 period in order to discern changes in population statistics by age groups and regions without interruption over time and to calculate the unemployment rates according to both broader and narrower definitions since 2004. / Bu çalışmada TÜİK Hanehalkı İşgücü Anketi’ninde 2014 yılında yapılan düzenlemelerden kaynaklanan bazı sonuçları bulguluyor, nüfus ve işsizlik istatistiklerinde yapılan revizyonların özellikle ikisinden kaynaklanan sorunların nasıl ele alınması gerektiği hakkında yol gösteriyoruz. İlk revizyon, anket ağırlıklarının dayandırıldığı yeni nüfus projeksiyonlarının kabul edilmesidir. İkincisi ise, dar tanımlı bir işsizlik tanımına geçilmesidir. Bu çalışmada 2014 öncesindeki anket ağırlıklarını nüfus istatistiklerinde yaş bazında ve bölgesel olarak kopma olmayacak şekilde yeniden ayarlamak ve işsizlik oranlarını geniş ve dar tanımlı olarak 2004 yılından itibaren hesaplamak için yöntemler öneriyoruz.Publication Metadata only A prospective, multicentered study to assess social adjustment in patients with an intestinal stoma in Turkey(H M P Communications, 2015) Karabulut, Hatice; Baykara, Zehra G.; Harputlu, Deniz; Toyluk, Eylem; Ulusoy, Birgul; Karadag, Sercan; Kahraman, Aysel; Hin, Aysel Oren; Altinsoy, Meral; Akil, Yasemin; Leventoglu, Sezai; N/A; Karadağ, Ayişe; Faculty Member; School of Nursing; 3549Patients with a stoma undergo physiological, psychological, and social adjustment to their new life situation. A descriptive, prospective study was conducted to assess adaptation among patients > 18 years of age with a new temporary or permanent colostomy or ileostomy living in Turkey and receiving care at a participating stomatherapy unit. The study took place between September 1, 2011, and September 1, 2012. During hospitalization and following discharge, patients with a stoma received training and counseling according to their individual characteristics and their physiological, psychological, and social needs. Each participant completed the 19-item "Identification Form for Patients with a Stoma" at the beginning of the study to document sociodemographic and stoma characteristics. To assess adjustment to the stoma, The Ostomy Assessment Inventory (OAI-23) was administered 2 times - he first within 1 month and the second within 6 months after surgery or when a temporary stoma was closed (whichever came first). This instrument comprised 23 items regarding adaptation to the stoma using Likert-type response options (0-4 range). Total scores ranged from 10 to 92, with higher scores indicating better adjustment. The instruments were completed by stoma and wound care nurses during face-to-face interviews. Data were analyzed using the Kruskal-Wallis, Mann-Whitney, and Wilcoxon tests. of the 135 participants, the majority (77, 57.0%) were male; 73 (54.1%) had a colostomy, and 106 (78.5%) had a temporary stoma. The primary reason for stoma creation was cancer (89, 65.9%). Mean total OAI-23 scores were 48.63 +/- 13.75 at the first administration and 50.59 +/- 13.89 for the second. In terms of sociodemographic factors, significant increases in mean scores from the first to the second survey time were noted among patients in the 50-69 age group, women, married persons, and unemployed persons (P < 0.05). With regard to stoma characteristics, the OAI-23 scores of patients with planned stoma operations and persons with permanent stomas increased significantly (P < 0.05) between assessments. Significant increases in OAI-23 scores also were noted among persons who did not receive information before the operation, patients whose stoma site was not marked, and patients who had experienced a complication (P < 0.05). Postoperatively, it is important to consider sociodemographic and stoma characteristics as well as preoperative variables that may influence adaptation to stoma. Additional larger, multicentered studies with extended patient follow-up are warranted.