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Item Metadata only Elevational patterns of species richness and community structure of understorey birds in an East African montane forest(Wiley, 2023) 0000-0003-3193-0377; Wambugu, Geoffrey M.; Amakobe, Bernard; Githiru, Mwangi; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; College of Sciences; 327589Mt. Kasigau is the northeastern most of the Eastern Arc Mountains global hotspot and harbours some endemic and threatened species, but little is known about bird community changes along its elevational gradient. We assessed the relationship between bird biodiversity metrics, season, human disturbance, elevation and temperature using mist-netting data collected bi-annually over a 10-year period. Birds were sampled along the mountain's elevational gradient at four elevation levels (858, 1104, 1321 and 1547 m). Bird richness, diversity and evenness decreased with increasing altitude in both dry and wet seasons. Bird abundance declined with increasing elevation for the lower three elevation levels but peaked at the highest elevation. All diversity metrics were higher in the wet season compared to the dry season across all the years. Elevation had a greater effect on species assemblages than season, disturbance and temperature. Temperature had significant effects on abundance, diversity and richness, while disturbance had significant effects on diversity, evenness and richness. We conclude that bird assemblages in Mt. Kasigau are strongly shaped by elevational changes, while temperature and disturbance constitute important factors influencing bird conservation in the face of global warming. Our study highlights that elevation, disturbance and temperature influence bird assemblages along tropical elevational gradients. Le mont Kasigau est le haut lieu mondial le plus au nord-est des montagnes de l'Arc oriental et abrite quelques especes endemiques et menacees, mais peu de choses sont connues sur les changements dans les communautes d'oiseaux le long de son gradient d'altitude. A l'aide de filets japonais collectes deux fois par an sur une periode de dix ans, nous avons evalue la relation entre les mesures de la biodiversite des oiseaux, la saison, les perturbations humaines, l'altitude et la temperature. Les oiseaux ont ete echantillonnes le long du gradient d'altitude de la montagne a quatre niveaux d'altitude (858 m, 1104 m, 1321 m et 1547 m). La richesse, la diversite et la regularite des oiseaux diminuent avec l'augmentation de l'altitude, tant en saison seche qu'en saison pluvieuse. En ce qui concerne les trois niveaux d'altitude inferieurs, l'abondance des oiseaux a diminue avec l'augmentation de l'altitude, mais a atteint son maximum a l'altitude la plus elevee. Quelle que soit l'annee, tous les parametres de diversite etaient plus eleves pendant la saison humide que pendant la saison seche. L'altitude a eu un effet plus important sur les assemblages d'especes que la saison, les perturbations et la temperature. La temperature a eu des effets considerables sur l'abondance, la diversite et la richesse, tandis que les perturbations ont eu des effets significatifs sur la diversite, la regularite et la richesse. Il ressort de cette etude que les assemblages d'oiseaux du Mont Kasigau sont fortement influences par les changements d'altitude, tandis que la temperature et les perturbations constituent des facteurs importants pour la conservation des oiseaux face au rechauffement de la planete.Item Metadata only A novel weight optimized dynamic conformal arcs with TrueBeam™ Linac for very small tumors (≤1 cc) with single isocenter of multiple brain metastases (2≤, ≥4) in stereotactic radiosurgery: a comparison with volumetric modulated arc therapy(Wolters Kluwer Medknow Publications, 2023) 0000-0003-1151-4616; N/A; Sağlam, Yücel; Doctor; School of MedicineIntroduction: We evaluated whether improved increase delivery efficiency of weight optimized dynamic conformal arc (WO-DCA) therapy in comparison to volumetric modulated arc therapy (VMAT) with single isocenter for SRS treatment of very small volume and multiple brain metastases (BMs). Materials and Methods: 20 patients having a less than 1 cc volume and 2 <=, >= 4 of multiple BMs, redesigned for 20 Gy in 1 fraction using WO-DCA and VMAT techniques with double full coplanar and three partial noncoplanar arcs. Plan qualities were compared using tumor coverage, conformity index (CI), gradient index (GI), V-4Gy, V-10Gy, and V-12Gy volumes of brain, monitor units (MUs), and percent of quality assurance pass rate (QA%). Results: Both techniques satisfied clinical requirements in coverage and CI. VMAT had a significantly higher MU and mean GI than WO-DCA (for MUs; 2330 vs. 1991; P < 0.001, and for GI; 4.72 vs. 3.39; P < 0.001). WO-DCA was found significantly lower V-4Gy (171.11 vs. 232.80 cm(3), P < 0.001), V-10Gy (25.82 vs. 29.71 cm(3), P < 0.05), and V-12Gy (14.35 vs. 17.28 cm(3), P < 0.05) volumes than VMAT. WO-DCA was associated with markedly increase QA pass rates for all plans (97.65% vs. 92.64%, P < 0.001). Conclusions: WO-DCA may be the first choice compared to the VMAT in reducing the dose in the brain and minimizing small-field dosimetric errors for very small SRS treatment of brain metastases in the range of <= 1 cc and 2 <=, >= 4.Item Metadata only The cultural self-construals and the romantic relationship experiences of Turkish young adults(Routledge Journals, Taylor and Francis Ltd, 2023) 0000-0003-3507-1290; 0000-0002-7546-9802; Department of Psychology; N/A; Erdem, Gizem; Safi, Ommay Aiman; Faculty Member; PhD Student; College of Social Sciences and Humanities; Graduate School of Social Sciences and Humanities; 222027; N/AThe capacity to form and maintain committed romantic relationships is a key aspect of young adulthood. Yet, little is known about the role of cultural factors, in particular cultural self-construal, and their links to romantic relationships. The goal of the current study was to examine the cultural concepts of autonomous and related self-construal as defined by Kagitcibasi's Family Change Theory and their association with the quality and satisfaction of non-marital romantic relationships. The sample included 621 Turkish young adults (74.4% female, 83.7% undergraduate students, ages 18-25) who were currently in an exclusive and heterosexual romantic relationship for at least three months. Participants completed informed consent and a 15-minute online survey through Qualtrics. Hierarchical linear regression analysis indicated that autonomy self-construal was positively associated with relationship quality and satisfaction, while relatedness self-construal was linked to relationship quality but not satisfaction. Additionally, high levels of commitment significantly predicted better relationship outcomes. The findings suggest a need to explore cultural self-construal and relationship outcomes across cultures.Item Metadata only Challenges in diagnosis and treatment of fasciola hepatica infection(DOC Design Informatics Co Ltd, 2023) 0000-0003-1935-9235; 0000-0003-3823-4454; 0000-0002-1840-0040; 0000-0002-1178-7449; N/A; N/A; N/A; N/A; Ergönül, Mehmet Önder; Keske, Şiran; Pınarlık, Fatihan; Rozanes, İzzet; Faculty Member; Faculty Member; PhD Student; Faculty Member; Koç Üniversitesi İş Bankası Enfeksiyon Hastalıkları Uygulama ve Araştırma Merkezi (EHAM) / Koç University İşbank Center for Infectious Diseases (KU-IS CID); School of Medicine; School of Medicine; Graduate School of Health Sciences; School of Medicine; 110398; 125555; N/A; 125890A 57-year-old female patient presented with fever, nausea, vomiting, loss of appetite, and weight loss within the last two months. Ceftriaxone and metronidazole therapy was start-ed upon discovery of a liver abscess but provided no benefit. Following the of abscess bi-opsy, the patient developed fever, itching, anemia, acute renal failure, hyperbilirubinemia, and eosinophilia that required intensive care unit (ICU) admission. The Fasciola hepatica antibodies were detected by enzyme-linked immunosorbent assay (ELISA). Triclabendazole was started, after which the symptoms and magnetic resonance imaging (MRI) findings regressed. Even without eosinophilia, F. hepatica should be considered in cases with a liver abscess that does not respond to antibiotics.Item Metadata only Temporary 6TH cranial nerve paralysis after accidental durotomy in endoscopic disc surgery(John Wiley and Sons Inc, 2023) 0000-0003-0524-9537; N/A; Avci, İdris; Gürsoy, Tansu; Özer, Ali Fahir; N/A; N/A; Şentürk, Salim; Yaman, Onur; Doctor; Doctor; N/A; N/A; Koç University Hospital; N/A; 219524We present a unique case of 6th nerve palsy following accidental durotomy in endoscopic lumbar spine surgery, which has not been reported in the literature before. A 72- year-old female patient was admitted to our outpatient clinic complaining of right leg pain for 6 months. A 4/5 motor paresis was observed on her right toe with a positive Lasegue test at 45°. On her magnetic resonance imaging (MRI), a L5-S1 disc herniation was detected. The patient was planned for percutaneous endoscopic interlaminar disc surgery. The extruded disc was adherent to the dura. During removal, a dural tear was observed. She was relieved of her right leg pain immediately after surgery, but after 30 min postoperatively, she complained of double vision with left abducens nerve paralysis. On cranial MRI, no abnormality could be observed. Intravenous fluids were administered and the paralysis resolved on the postoperative 24th hour. The patient was discharged from the hospital and did not show any complaints on her follow-ups. A 6th nerve palsy can be caused due to alterations of intracranial pressure or mechanic injury. We believe that the durotomy following removing of the disc fragment caused a rapid drainage of CSF, leading to intracranial hypotension and injury of the abducens nerve. Intracranial pressure should be monitored perioperatively and brisk deteriorations has to result in immediate finishing of the surgery to avoid further secondary damage. © 2022 Asia Endosurgery Task Force and Japan Society of Endoscopic Surgery and John Wiley & Sons Australia, Ltd.Item Metadata only MTTF and availability of semi-Markov missions with non-identical generally distributed component lifetimes(Taylor and Francis Ltd., 2023) 0000-0003-3610-1746; Çekyay, Bora; Department of Industrial Engineering; Özekici, Süleyman; Faculty Member; College of Engineering; 32631We analyze mean time to failure and availability of systems that perform semi-Markov missions. The mission process is the minimal semi-Markov process associated with a Markov renewal process. Therefore, the successive phases of the mission follow a Markov chain, and the phase durations are generally distributed. The lifetimes of the non-identical components in the system are assumed to be generally distributed and are modeled using intrinsic aging concepts. Moreover, the lifetime parameters of the components and the configuration of the system change depending on the phases of the mission. We characterize the mean time to failure through solving a Poisson equation, and we analyze the system availability assuming that repair duration has a general distribution which is dependent on the phase of the mission during which the failure has occurred and on the deterioration level of the system. © 2022 Taylor & Francis Group, LLC.Item Metadata only Feasibility of totally extraperitoneal inguinal hernia repair in patients with previous prostatectomy(Turkish Surgical Assoc, 2023) 0000-0001-6749-8518; 0000-0001-5751-1133; N/A; 0000-0002-3610-7390; 0000-0002-9227-9015; 0000-0001-7971-3772; N/A; 0000-0002-9371-6811; 0000-0003-1617-3953; 0000-0003-0316-6818; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; N/A; Özata, İbrahim Halil; Balık, Emre; Sucu, Serkan; Karahan, Salih Nafiz; Camcı, Furkan; Bozkurt, Emre; Kılıçoğlu, Bilge Kaan; Özoran, Emre; Ağcaoğlu, Orhan; Buğra, Dursun; Kalender, Mekselina; Teaching Faculty; Faculty Member; Researcher; Researcher; Undergraduate Student; Doctor; Undergraduate Student; Teaching Faculty; Faculty Member; Faculty Member; Undergraduate Student; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; 177151; 18758; 327623; 337050; N/A; N/A; N/A; 307296; 175476; 1758; N/AObjective: Laparoscopic totally extraperitoneal inguinal hernia repair (TEP) surgery technique includes three key steps: reaching the preperitoneal space, reducing hernias, and placement of mesh. However, reaching the preperitoneal space can be complicated in patients with previous lower abdominal surgeries. This study aimed to assess the feasibility of laparoscopic inguinal TEP in patients with previous prostatectomies. Material and Methods: Inguinal hernia patients who underwent laparoscopic TEP between January 2015 and February 2021 at Koc University Faculty of Medicine, Department of General Surgery, were included in this retrospective study. The operations were performed by five senior surgeons experienced in laparoscopy. Patients were divided into two study groups, as the radical prostatectomy (RP) group which included patients with previous prostatectomy non-RP which included patients without previous radical prostatectomy. Operative time (OT), length of hospital stay (LOS), and postoperative complications were compared within two groups. Results: Three hundred and forty-nine patients underwent laparoscopic TEP, and 27 had previous prostatectomies. Among them, 190 patients had unilateral inguinal hernias, and 159 had bilateral inguinal hernias. Mean age of the patients in the non-RP and RP groups was 58.1 +/- 14.7 and 73.9 +/- 9.6 years, respectively. Only one (3.7%) case was complicated with urinary tract infection in the RP group, and 10 (3.1%) were complicated in the non-RP group. Complications for the non-RP group include hematomas in six cases, urinary tract infection in three cases, and urinary retention in one case. No significant difference in mean operative time was seen between non-RP and RP groups (p= 0.43). There was no significant difference in the means of the length of hospital stay between the two groups (p= 0.7). Conclusion: Laparoscopic TEP in patients with a previous prostatectomy can be performed safely without prolonging the operative time and increasing the length of hospital stay.Item Metadata only Is an arbitration agreement in a fixed term contract enforceable in the event of the de facto continuation of the relationship at the end of the term? Critique of a recent decision by the 11th civil chamber of the court of cassation(Istanbul Univ, 2023) 0000-0002-1332-7083; N/A; Önay, Işık; Faculty Member; Law School; 122220This article deals with a specific problem regarding the interpretation and scope of arbitration agreements. Following the expiration of the term in a contract pertaining to a continuous legal relationship, parties sometimes continue their relationship within the framework of the same (or similar) rights and obligations without entering into a further agreement explicitly. In such a case, the problem arises of whether the arbitration clause regarding the first contract covers disputes arising out of the legal relationship that continues beyond the initially agreed-upon term. In order to answer this question, what the de facto continuation of the legal relationship between the parties means should first be determined in terms of law of obligations. Have the parties implicitly extended the term of the contract between them, or have they implicitly established a new contract with the same content? With respect to this controversial issue, the author argues that the will of the parties as a rule is in favor of the first alternative. Secondly, answering the question requires an interpretation of the arbitration agreement to determine its scope. The interpretation of arbitration agreements is ultimately governed by the general principles of contract interpretation. According to the view advocated in this study, arbitration agreements should be interpreted broadly and in line with the trends in international arbitration. The explanatory notes by the legislator regarding arbitration legislation also support this approach. Meanwhile, the decisions by the Turkish Court of Cassation generally tend to interpret arbitration agreements restrictively. The decision this study analyzes shows the Court of Cassation to have ruled that a new contract was established between the parties with respect to a distributorship relationship, which the parties continued after the expiry date that had been initially included in the contract. The Court of Cassation concluded that the disputes arising from this contract should be resolved before the state courts, as the parties' intention to submit disputes arising from this new contract to arbitration could not be ascertained. The study hereby argues that this decision of the Court of Cassation is open to criticism in light of the trends in international arbitration.Item Metadata only The west versus the rest: the Russian invasion of Ukraine and the crisis of the "post-western" order(Turkish Policy Quarterly, 2022) 0000-0002-0129-2944; Department of International Relations; Öniş, Ziya; Faculty Member; College of Administrative Sciences and Economics; 7715The Russian invasion of Ukraine intensified the defining conflict of the new age, the conflict between democratic and authoritarian capitalism. The unified Western response to the war highlighted the revitalization of the democratic club of Western states and their allies (G7 plus). Another critical implication of the War has been that a clear divide has emerged between "the West" and "the Rest" in their reactions to the War. The Russian War on Ukraine signals the beginnings of a new phase of the post-Western world, where territorial conquests could be considered the new normal, paving the way for further military confrontations in a conflict-ridden World.Item Metadata only The role of FDG positron emission tomography/contrast-enhanced computed tomography in preoperative staging and postoperative follow-up in rectal cancer surgery(Index Copernicus Int, 2022) 0000-0002-2590-5872; 0000-0003-4234-9078; Kulle, Cemil Burak; Ozkan, Zeynep Gozde; Azamat, Sena; Keskin, Metin; Bulut, Mehmet Turker; N/A; N/A; Uymaz, Derya Salim; Omarov, Nail; Teaching Faculty; Doctor; School of Medicine; N/A; Koç University Hospital; 175554; N/AIntroduction: F-18 fluorodeoxyglucose (F18-FDG) positron emission tomography-computed tomography (PET/CT) is a valuable functional imaging modality for the clinical diagnosis which provides physiological information based on the altered tissue metabolism. Aim: This study aims to investigate the effectiveness of F-18 fluorodeoxyglucose (F18-FDG) positron emission tomography-computed tomography (PET/CT) in preoperative staging and postoperative local recurrence and distant metastases in patients with rectal cancer. Material and methods: The imaging of 726 patients with rectal cancer who were operated on at Istanbul University, Istanbul School of Medicine and had F18-FDG PET/CT, CT, and magnetic resonance imaging (MRI) scans between September 2005 and October 2016 were retrospectively analyzed. Of these patients, 170 who had pre- and postoperative PET/CT scans, had their CT scans included in the study. The sensitivity and specificity of PET/CT in preoperative staging and detection of postoperative local recurrence and distant metastases were analyzed. Results: Of the patients, 101 were males and 69 were females with a median age of 62.27 (range, 31 to 89) years. The sensitivity and specificity of preoperative PET/CT in detecting liver metastases were 100% (confidence interval [CI]: 66.37-100%) and 94.2% (CI: 89.72-100%), respectively (Cohen's kappa [kappa]: 1.00; P < 0.001). The sensitivity and specificity of postoperative PET / CT in diagnosing liver metastases were 100% (CI: 88.06-100%) and 98% (CI: 9-100%), respectively (Cohen's kappa: 1.00; P < 0.001). The sensitivity and specificity of preoperative PET/CT in detecting lung metastases were 100% (CI: 66.37-100%) and 91.8% (CI: 89.72-100%), respectively (Cohen's kappa: 1.00; P < 0.001). The sensitivity and specificity of postoperative PET/CT in detecting lung metastases were 100% (CI: 91.4-100%) and 96% (CI: 95.8-100%), respectively (Cohen's kappa: 1.00; P < 0.001). The sensitivity and specificity of PET/CT in preoperative staging of pathological pelvic lymph nodes were 100% (CI: 63.06-100%) and 94.29% (CI: 80.84-99.3%), respectively (Cohen's kappa: 0.860; P < 0.001). The sensitivity and specificity of postoperative PET/CT in detecting local recurrences were 100% (CI: 78.2-100%) and 76.74% (CI: 61.37-88.24%), respectively (Cohen's kappa: 0.219; P < 0.08). Results: Given the fact that PET/CT can detect all primary rectal cancer in preoperative staging, it can be effectively used in selected cases, particularly in those suspected of local and advanced disease and with metastases (T3N0, T3N1, and/or T4N1). Due to a relatively low specificity in detecting local recurrences postoperatively,PET/CT can be combined with further modalities.