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Permanent URI for this collectionhttps://hdl.handle.net/20.500.14288/3
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Publication Metadata only Influence of soft segment structure, hydrogen bonding, and diisocyanate symmetry on morphology and properties of segmented thermoplastic polyurethanes and polyureas(Tubitak Scientific & Technological Research Council Turkey, 2023) Department of Chemistry; Yılgör, Emel; Yılgör, İskender; Department of Chemistry; College of SciencesA comprehensive review of the structure-morphology-property relations in segmented thermoplastic polyurethanes and polyureas (TPU) is provided. Special emphasis is given to the influence of the soft segment structure, polarity, and molecular weight, diisocyanate symmetry and the nature, extent, and strength of hydrogen bonding on the morphology and thermal and mechanical properties of TPUs. Experimental results obtained on composition-dependent TPU morphology and properties by various techniques were also compared by the morphology profiles generated by computational methods such as quantum mechanical calculations and molecular dynamics simulations.Publication Metadata only The effect of whole-body vibration on spasticity in post-stroke hemiplegia: a prospective, randomized-controlled study(Baycinar Medical Publ-Bayçınar Tıbbi Yayıncılık, 2022) Yurttutmus, Zeynep Rukiye; Zincirci, Dilara Ekici; Bardak, Ayse Nur; Karacan, Ilhan; Türker, Kemal Sıtkı; School of MedicineObjectives: This study aims to investigate whether whole-body vibration (WBV) has an anti- spastic effect on the ankle plantar flexors. Patients and methods: This single-blind, prospective, randomized-controlled clinical study included a total of 48 patients with chronic stroke (33 males, 15 females; mean age: 60.7 +/- 10.9 years; range, 25 to 80 years) between May 2019 and February 2020. They were randomized into two groups: WBV group (n=24) and sham WBV group (n=24). A training program of 12 sessions (three days a week for four weeks) was applied regularly in both groups. The spasticity degree of the plantar flexors was evaluated by using both a subjective assessment method (modified Ashworth scale [MAS]) and several objective assessment methods (H-max/M-max, homosynaptic post-activation depression [HPAD], and torque) before and after the training program. Results: There were no significant changes in the torque values, H-max/M-max, and HPAD level after the training program in both groups (p>0.05). However, the MAS score in the WBV group significantly decreased (-9.0%), but no change in the control group was observed (0.7%) (p=0.027, effect size = 0.32). Conclusion: The objective assessment methods for spasticity show that WBV has no anti-spastic effect.Publication Metadata only The impact of the Covid-19 pandemic on children with disabilities and their parents or caregivers(Baycinar Medical Publ-Bayçınar Tıbbi Yayıncılık, 2023) Capan, Nalan; Saygi, Evrim Karadag; Yalcinkaya, Ebru Yilmaz; Huener, Berrin; Aydin, Resa; Taşkıran, Özden Özyemişçi; School of MedicineObjectives: The study aimed to determine the impact of the pandemic on parents/caregivers and children with neurologic disabilities.Patients and methods: This multi-center cross-sectional study was conducted with 309 parents/caregivers (57 males, 252 females) and their 309 children (198 males, 111 females) with disabilities between July 5, 2020, and August 30, 2020. The parents/caregivers were able to answer the questions and had internet access. The survey included questions on the utilization of educational and health care services (whether they could obtain medicine, orthosis, botulinum toxin injection, or rehabilitation) during the pandemic. A Likert scale was used to evaluate the effect of the specific health domains, including mobility, spasticity, contractures, speech, communication, eating, academic, and emotional status. The Fear of Covid-19 Scale was used to assess fear of Covid-19.Results: Among the children, 247 needed to visit their physician during the pandemic; however, 94% (n=233) of them could not attend their physician appointment or therapy sessions. The restricted life during the first wave of the pandemic in Turkiye had negatively affected 75% of the children with disabilities and 62% of their parents. From the perspective of the parents/caregivers, mobility, spasticity, and joint range of motion of the children were affected. Forty-four children required repeated injections of botulinum toxin; however, 91% could not be administered. The Fear of Covid-19 Scale scores were significantly higher in the parents who could not bring their children to the routine physician visit (p=0.041). Conclusion: During the pandemic, access to physical therapy sessions was disrupted in children with neurological disabilities, and this may have harmful consequences on the functional status of children.Publication Metadata only Intraoperative fluoroscopic safety assessment of femoral head implants with 3-dimensional risk parameters to minimize cut-out(Turkish Assoc Orthopaedics Traumatology, 2023) Department of Mechanical Engineering; Subaşı, Ömer; Aslan, Lercan; Oral, Atacan; Demirhan, Mehmet; Seyahi, Aksel; Lazoğlu, İsmail; Department of Mechanical Engineering; Manufacturing and Automation Research Center (MARC); Graduate School of Sciences and Engineering; School of Medicine; College of EngineeringObjective: This study aimed to introduce a method to extract the 3-dimensional spatial position of the femoral head implant from 2-dimensional fluoroscopic projections, allowing surgeons to assess fixation much more accurately and prevent cut-out complications in proximal femoral nailing. Methods: To define a safety region for the tip in the femoral head, a novel 3-dimensional distance-based risk parameter called TSD3D was introduced. An intersection algorithm was developed that solely takes the fluoroscopic anteroposterior and lateral distances to reveal the 3-dimensional location of the screw or Kirschner wire tip, enabling the utilization of the 3-dimensional parameter. Orthogonal perspectives of 6 femur proximal bone substitutes with randomly inserted Kirschner wires were imaged under fluoroscopy. The developed algorithm was used to calculate the implant tip location in 3-dimensional from 2-dimensional images for each case. Algorithm accuracy was validated with the computed tomography-obtained 3-dimensional models of the same femur substitutes. Results: The newly introduced risk parameter successfully visualizes 3-dimensional safety regions. Utilizing the 2-dimensional fluoroscopic distances as inputs to the algorithm, the 3-dimensional position of the implanted Kirschner wire tip is calculated with a maximum of 9.8% error for a single Cartesian-coordinate measurement comparison. Conclusion: By incorporating the newly introduced 3-dimensional risk parameter, surgeons can more precisely evaluate the position of the implant and avoid cut-out complications, instead of relying solely on misleading 2-dimensional fluoroscopic projections of the femoral head.Publication Metadata only Comparison of perinatal and neonatal outcomes of symptomatic pregnancy infected with SARS-CoV-2(Galenos Publishing House, 2024) Arslan, Oguz; Tug, Niyazi; Giray, Burak; School of MedicineObjective: In this study, maternal and neonatal outcomes of pregnant women with positive severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) RNA tests were evaluated according to their symptomatic status. The clinical progression of SARS-CoV-2-positive pregnant women and the effect of coronavirus disease-2019 (COVID-19) on newborns was investigated. Material and Methods: This retrospective cohort study was conducted at a tertiary pandemic hospital specializing in caring for pregnant women infected with SARS-CoV-2. We included patients with a positive SARS-CoV-2 polymerase chain reaction test at delivery, subdividing them into symptomatic and asymptomatic groups.
Results: Two hundred and forty-nine patients were included in the study. The mean age of the pregnant women in the symptomatic group was higher than those in the asymptomatic group (p=0.001). The iatrogenic preterm birth rates in the symptomatic and asymptomatic groups were 43.37% and 8.43%, respectively (p<0.001). Cesarean section rate was higher in symptomatic group (p=0.01). Maternal death was significantly higher in symptomatic pregnant women (p<0.001). The neonatal intensive care unit admission rate was higher in symptomatic pregnant women (p<0.001).
Conclusion: The maternal and fetal outcomes for mothers with symptomatic infections tend to be worse, highlighting the importance of careful management, good follow-up and the advisability of closer monitoring.Publication Metadata only Politicization, ratification of international agreements, and domestic political competition in non-democracies: the case of Iran and the Paris Climate Accords(International Relations Council of Turkey, 2024) Department of International Relations; Bayer, Reşat; Tafazzoli, Bijan; Department of International Relations; College of Administrative Sciences and Economics; Graduate School of Social Sciences and EconomicsWhile some degree of competition is present in many authoritarian regimes, the implications of such controlled competition on international issues have not received much consideration, including towards international environmental accords. We attempt to rectify this through a framework where we focus on internal political competition in a hybrid, nondemocratic system where national elections are held regularly. Specifically, we argue that the presence of multiple actors competing in elections in nondemocratic settings results in them assuming positions on various issues, justifying their positions, and attempting to mobilize their supporters with considerable implications for international environmental policies. We display our argument in the context of Iranian debates on the ratification of the Paris Climate Accords. Our findings demonstrate that the competing Iranian sides rely on different justifications for their environmental positions, resulting in extensive (negative) competitions of rhetoric where the international dimension emerges as an important feature in the internal competition. Overall, we show that political competition within non-democracies is likely to add to the complexity of international (environmental) negotiations and cooperation. © 2024, INTERNATIONAL RELATIONS. All rights reserved.Publication Metadata only Pain types and risk factors in post-Covid-19(Baycinar Medical Publ-Baycinar Tibbi Yayincilik, 2024) Zure, Mert; Akpinar, Fatma Merih; Ozdemir, Yelda Soluk; Balbaloglu, Oezlem; Akaltun, Mazlum Serdar; Erden, Ender; Turk, Ayla Cagliyan; Korkmaz, Merve Damla; Okmen, Burcu Metin; Altindag, Oezlem; Soyupek, Feray; Yaksi, Elif; Sindel, Dilsad; Sezgin, Nalan; Ustaomer, Kubra; Kesiktas, Fatma Nur; Dere, Didem; Gunes, Sevket; Ceylan, Cansin Medin; Tur, Birkan Sonel; Evcik, Deniz; N/A; Ketenci, Ayşegül; School of MedicineObjectives: This study aims to accurately evaluate pain lasting longer than three months and falls under the category of chronic pain and to determine the risk factors to follow up and treat properly and to develop appropriate diagnostic and treatment algorithms. Patients and methods: Between March 2021 and December 2021, a total of 437 patients (162 males, 275 females; mean age: 44 +/- 14.6 years; range, 12 to 82 years) who were referred to the participating centers due to pain complaints and were diagnosed with post-COVID-19 condition according to the criteria defined by the World Health Organization (WHO) were included in the study. The patients were divided into three groups as nociceptive pain, neuropathic pain, and central sensitization, based on the physician's clinical evaluation and the Self-Report Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS) and Central Sensitization Inventory scores. Results: The most common diagnosis was nociceptive pain followed by central sensitization. Patients with nociceptive pain had less pain. It was found that not exercising regularly, having a chronic disease and being a woman were risk factors for central sensitization, having thyroid disease before COVID-19, and defining the current pain as very severe were risk factors for neuropathic pain. Conclusion: In the evaluation of post-COVID-19 pain, neuropathic pain and central sensitization should be also considered in addition to nociceptive pain and the severity of pain, systemic diseases and physical activity should be questioned.Publication Metadata only Is it possible to objectively determine morning stiffness in rheumatoid arthritis?(Baycinar Medical Publ-Bayçınar Tıbbi Yayıncılık, 2024) Mengi, Gönen; Aydoğmuş, Hüseyin; Göğüş, Feride; Beyazova, Mehmet; N/A; Taşkıran, Özden Özyemişçi; School of MedicineObjectives: This study aimed to objectively and quantitatively exhibit morning stiffness by using electrophysiological methods. Patients and methods: The prospective, controlled study was conducted with 52 participants between February 2013 and February 2014. Of the participants, 26 were recruited among RA patients (3 males, 23 females; mean age: 55.9±11.2 years; range, 24 to 74 years) followed at the rheumatology clinic, and 26 were healthy subjects (4 males, 22 females; mean age: 54.9±8.3 years; range, 41 to 70 years) for the control group. Duration and severity of morning stiffness were recorded for all participants. Activity of disease and functional status were evaluated by the Disease Activity Score 28 and Health Assessment Questionnaire (HAQ), respectively. Electrophysiological reaction times, severity of pain (Visual Analog Scale), HAQ, and grip strength were measured for each participant twice in 24 h in the morning (08:00-09:00 am) and afternoon (03:00-05:00 pm). Results: In the RA group, motor reaction and response times and severity of pain values were significantly lower in the afternoon compared to the morning (p=0.030, p=0.031, and p=0.002, respectively), and hand grip strengths were significantly higher in the afternoon (p=0.007). In the control group, no change was observed between morning and afternoon measurements in the strength and reaction time variables. Conclusion: Our hypothesis that stiffness would slow down the movements in the morning in RA was supported by the prolonged motor and response times in the morning compared to the afternoon. However, in the control group (no morning stiffness), there was no difference in reaction time variables between the morning and afternoon, objectively demonstrating the concept of morning stiffness in this study. © 2024 Turkish Society of Physical Medicine and Rehabilitation. All rights reserved.Publication Metadata only Does fear of activity predict exercise capacity in patients with coronary artery disease in both sexes? A cross-sectional multicenter study(Baycinar Medical Publ-Bayçınar Tıbbi Yayıncılık, 2024) Demirsoy, Nesrin; Atan, Tugba; Durmus, Dilek; Tur, Birkan Sonel; Findikoglu, Gulin; Guzel, Rengin; Uzumcugil, Hale; Eksioglu, Emel; Sarikaya, Selda; Soyupek, Feray; Ayhan, Fikriye Figen; Kabayel, Derya Demirbag; Ozdemir, Hande; Duran, Ummugulsum Dogan; Aydemir, Koray; Karaahmet, Ozgur; Sutbeyaz, Serap; Aytur, Yesim Kurtais; Dulgeroglu, Deniz; N/A; Taşkıran, Özden Özyemişçi; School of MedicineObjectives: This study aimed to identify whether fear of activity predicts exercise capacity in patients with coronary artery disease (CAD) and whether there is a difference between sexes regarding this relationship. Patients and methods: One hundred ninety-seven patients (145 males, 52 females; mean age: 56.3 +/- 10.8 years; range, 22 to 80 years) with a diagnosis of CAD or cardiac event in the previous one to 60 months were enrolled in this cross-sectional multicenter study between November 2015 and February 2017. Demographic and clinical features were recorded. Fear of activity was assessed by the fear of activity scale in patients with CAD (FactCAD). A 6 -min walk test was used to assess exercise capacity. Results: Female participants were older, less educated, and less employed (p=0.045, p=0.048, and p<0.001, respectively) than males. Prevalence of myocardial infarction was higher in males. Comorbidities were higher in females. Multiple linear regression predicted 6 -min walk distance (6MWD) based on FactCAD, sex, and education level with an r -squared of 0.321 (p<0.001). Fear of activity had an effect on walking distance in males (each additional score of FactCAD predicts a decrease of 1.3 m in 6MWD), together with disease duration, presence of chronic pulmonary disease, and low back pain, whereas fear of activity was not a predicting factor on walking distance in females. Age, education, and presence of angina predicted 6MWD in females. Conclusion: This study emphasizes that fear of activity is one of the predictors of 6MWD in males with CAD, and its assessment is recommended as a possible barrier to rehabilitation.Publication Metadata only Effect of platelet-rich plasma injections versus placebo on pain and quality of life in patients with hip osteoarthritis: a double-blind, randomized clinical trial(Baycinar Medical Publ-Baycinar Tibbi Yayincilik, 2024) Sen, Ekin Ilke; Diracoglu, Demirhan; N/A; Topaloğlu, Mahir; Sarıkaya, Deniz; School of Medicine; Koç University HospitalObjectives: This study aims to compare the efficacy of intra-articular platelet -rich plasma (PRP) injections over a saline placebo in terms of reduction of pain and impact on quality of life among patients with hip osteoarthritis. Patients and methods: A total of 60 patients (29 males, 31 females, mean age: 57.9 +/- 7.3 years; range, 47 to 69 years) with known hip osteoarthritis of Kellgren-Lawrance (KL) Grades 2/3 were randomized into placebo (n=30) and PRP groups (n=30) between June 2014 and June 2015. Both groups received intra-articular injections into the hip joint under ultrasound guidance for three consecutive weeks. The patients were followed for six months, and pain reduction was assessed using the Visual Analog Scale (VAS), Western Ontario and McMaster Universities Arthritis Index (WOMAC) questionnaire, and Short Form Health Survey -36 (SF -36). Results: Intra-articular PRP treatment showed no advantage over a saline placebo in terms of VAS scores during activity. Both groups showed a significant improvement in VAS activity scores at one and six months. The placebo group showed improvements in VAS resting scores, whereas the PRP group did not. Both groups showed no improvement in WOMAC-total scores. Both groups showed no significant improvement across most SF -36 domains with the exception of improved physical role functioning at one month and general health at one and six months in the placebo group. Conclusion: Intra-articular injections of PRP show no significant difference compared to a saline placebo over a period of six months on pain, function, and quality of life scores in patients with hip osteoarthritis.