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Öğe Atık Madeni Yağ İçeren Kapsüllerin Bitümlü Sıcak Karışımların Mekanik Özelliklerine Etkisi(Hüseyin AKBULUT, 2022) Sarışın, Esma; Yilmaz, Mehmet; Yalçın, ErkutGünümüzde ulaşım açısından bitümlü sıcak karışımların önemi oldukça fazladır. Bitümlü sıcak karışımlar zamanla artan trafik yükü ve iklim koşullarına bağlı olarak rijitliğin artmasıyla kırılgan hale gelmektedir. Bu durum üst yapıda çatlaklara ve bozulmalara neden olmaktadır. Bu nedenle bitümlü karışım tabakalarının düzenli olarak gözlenmesi, bakım ve onarım faaliyetlerinin gerçekleştirilmesi gerekmektedir. Ancak ekonomik veya teknik nedenlerden ötürü bu her zaman mümkün olmayabilir. Bu nedenle kendini onarabilen bitümlü sıcak karışım fikri son yıllarda önem kazanmıştır. Çalışma kapsamında kapsüllerde onarıcı malzeme olarak araçların bakımları sonrası açığa çıkan atık madeni yağ kullanılmıştır. Optimum şartları sağlayan kapsüller üretilmiştir. Kapsüller, karışımlara dört farklı oranda (agrega ağırlığınca %0,25, %0,50, %0,75 ve %1,00) ilave edilmiştir. BSK numunelerine üç noktalı eğilme yorulma deneyi uygulanmıştır. Ayrıca kapsül ilavesinin karışımların mekanik özellikleri üzerindeki etkisini değerlendirilmiştir.Öğe Comparison of antirotation proximal femoral nail and talon locking nail systems in the treatment of intertrochanteric fractures: functional and cost-effectiveness outcomes(Springer, 2025) Guzel, Ismail; Ulusoy, Ibrahim; Tantekin, Mehmet Firat; Yilmaz, Mehmet; Kivrak, AybarsPurpose This study aimed to compare the clinical outcomes and cost-effectiveness of two widely used intramedullary fixation systems-the Proximal Femoral Nail Antirotation (PFNA) and the Proximal Femoral Nail with Talon Locking System (PFN-TLS)-in the treatment of intertrochanteric femur fractures (ITFF). MethodsA retrospective cohort study was conducted on 118 patients aged 65-90 years who underwent surgical treatment for ITFF using either PFNA (n = 53) or PFN-TLS (n = 65). All patients were followed for a minimum of 24 months. Preoperative functional evaluation was unavailable; outcomes were assessed at 24 months postoperatively. Surgical parameters, complication and revision rates, functional outcomes (Harris Hip Score [HHS], Visual Analog Scale [VAS], and SF-36), and health-economic indicators (Quality-Adjusted Life Years [QALY], Incremental Cost-Effectiveness Ratio [ICER]) were evaluated. Binary logistic regression analysis was performed to determine independent predictors of favorable functional outcomes. Results The PFN-TLS group demonstrated significantly shorter surgical duration, reduced incision length, and lower fluoroscopy exposure (p < 0.05). At the 24-month follow-up, HHS was significantly higher in the PFN-TLS group (82.7 +/- 7.4) compared to the PFNA group (76.4 +/- 8.1; p = 0.001). VAS and SF-36 scores were also higher, although not statistically significant. Revision rates showed a non-significant trend favoring PFN-TLS. QALY gains were slightly higher in the PFN-TLS group (0.530 vs. 0.449), with a lower cost per QALY ($1,637.93 vs. $1,863.22). PFN-TLS use was independently associated with favorable functional outcomes (OR: 2.62; 95% CI 1.23-5.58; p = 0.013). Conclusion Both PFNA and PFN-TLS are effective options for the management of ITFF. However, PFN-TLS may offer additional clinical and economic benefits, including improved functional outcomes and greater cost-efficiency. Findings should be interpreted with caution due to the retrospective design. Prospective, randomized studies are needed to validate these results and guide implant selection in clinical practice.Öğe Comparison of Intravenous, Topical, and Control Groups in Blood Management During Total Hip Arthroplasty: A Retrospective Analysis(Wiley, 2026) Guzel, Ismail; Ulusoy, Ibrahim; Yilmaz, Mehmet; Tantekin, Mehmet Firat; Kivrak, AybarsObjective Total hip arthroplasty (THA) is a widely performed surgical intervention for managing severe hip pathologies. However, this procedure is often associated with substantial blood loss and an increased need for blood transfusion. Tranexamic acid (TXA), a synthetic antifibrinolytic agent, is frequently administered to mitigate perioperative bleeding. Despite its widespread use, the comparative efficacy and safety of intravenous (IV) and topical TXA administration remain subjects of ongoing debate in the literature. Materials and Methods This retrospective, single-center study evaluated 45 patients who underwent primary THA between 2020 and 2024. The patients were divided into three groups based on TXA administration: IV TXA (n = 15), topical TXA (n = 15), and a control group without TXA (n = 15). Outcomes assessed included perioperative blood loss, transfusion requirements, postoperative hemoglobin decrease, and thromboembolic complications. Group comparisons were further adjusted for baseline confounders using analysis of covariance and multivariable logistic regression. Statistical significance was set at p < 0.05. Results Both IV and topical TXA administration significantly reduced perioperative blood loss compared with the control group. Transfusion rates were numerically lower in the TXA groups, although these differences did not reach statistical significance after adjustment. Mean blood loss was recorded as 820 mL in the IV TXA group, 840 mL in the topical TXA group, and 1100 mL in the control group. No significant difference was found between the IV and topical TXA groups, while both were superior to the control group in terms of hemoglobin decline. Thromboembolic complications and surgical site infection rates were comparable across all groups. Discussion The findings of this study demonstrate that both IV and topical TXA administration provide effective and safe control of perioperative bleeding in THA. The low incidence of thromboembolic events supports the safe use of TXA in clinical practice. Selection of the TXA administration route can be tailored based on patient-specific clinical conditions and the surgeon's preference. Conclusion In conclusion, the appropriate use of TXA during THA effectively reduces the need for blood transfusion and contributes to improved surgical outcomes. These results highlight the value of TXA as a reliable hemostatic agent in modern orthopedic surgery.Öğe Composite Modifiers to Improve the Rheological Properties of Asphalt Binders(Asce-Amer Soc Civil Engineers, 2024) Yalcin, Beyza Furtana; Bakir, Esma; Yalcin, Erkut; Yilmaz, MehmetFor the last 20 years, researchers have been looking for ways to modify asphalt binders to improve their rheological and thermophysical properties. The application of composite modifiers to enhance the rheological properties of asphalt binders offers a potential remedy for this significant issue. Because of this, this study looked at how composite modifiers affected the plain binder's rheological characteristics. This study examined the rheological properties of unmodified and modified binders using a variety of formulations to blend modifiers including linear styrene-butadiene-styrene (SBS), radial SBS, Elvaloy, and polyphosphoric acid (PPA). The effect of PPA on the properties of polymer-added binders at low temperatures was investigated. Additionally, modifications using PPA aim to reduce the polymer content. Based on traditional performance classification (PG) and multiple stress creep recovery (MSCR) systems, original, rolling thin film oven-aged, and pressure aging vessel-aged binders were divided into three groups using a dynamic shear rheometer (DSR). The performance of binders at low temperatures was also assessed using the bending beam rheometer (BBR). All of the study's additions were discovered to have enhanced the neat binder's high-temperature capabilities. The elastic property of the neat binder was increased by the addition of Elvaloy and PPA. Results showed that, although the PPA modifier reduced the hardness of neat asphalt binder at low temperatures, other additives did not show significant effects on the hardness of the binder. The MSCR procedure was successfully utilized to grade all of the binders, but it appears that some binders and conditions do not fit the MSCR protocol's percent difference criterion. According to the study's findings, SBS can be replaced by 611 elastomer to enhance the performance of binders at high and moderate temperatures.Öğe Development of anaphylaxis during biopsy of cardiac, hepatic, and subcutaneous hydatid cysts(2025) Yilmaz, Mehmet; Pirimoglu, Rüstem Berhan; Guzel, Ismail; AYERDEN, Dila; Ucmak, HacerThis case report presents a rare occurrence of both subcutaneous and cardiac hydatid cysts in a pediatric patient. A 10-year-old girl admitted with a rapidly enlarging, painful mass in the right dorsal scapular region. During a biopsy procedure under sedation, the patient developed an anaphylactic reaction and subsequent cardiopulmonary arrest. After successful resuscitation, cardiac echocardiography revealed a large hydatid cyst in the interventricular septum. In conclusion, potential complications should always be considered during invasive procedures. In addition, in patients with musculoskeletal masses, a whole-body magnetic resonance imaging may detect and prevent potential complications at an early stage.Öğe Early Versus Delayed Plate Fixation in Pilon Fractures-Which Is More Advantageous?(Mdpi, 2026) Guzel, Ismail; Ulusoy, Ibrahim; Yilmaz, Mehmet; Tantekin, Mehmet Firat; Kivrak, AybarsBackground: Pilon fractures refer to distal tibial fractures that may involve extra-articular, partial articular, or complete intra-articular components, most commonly caused by high-energy trauma. The choice between early (<72 h) and delayed (>7 days) surgical fixation significantly impacts clinical outcomes. This study aimed to compare the effects of early vs. delayed plate fixation on fracture healing time, functional outcomes, and complication rates. Materials and Methods: This retrospective study analyzed 80 patients who underwent surgical treatment for pilon fractures between 2018 and 2023. Patients were divided into two groups: early surgery (<72 h, n = 40) and delayed surgery (>7 days, n = 40). Additionally, patients were categorized based on the fixation method: single-plate fixation (n = 40) and double-plate fixation (n = 40). Outcome measures included fracture healing time (weeks), defined as cortical continuity on radiographs; functional outcomes (AOFAS score); and complication rates (infection, malunion, and implant failure). Results: Shorter healing time was observed in the early surgery group (14.2 vs. 16.8 weeks, p < 0.05). Better functional outcomes were recorded in the early surgery group (AOFAS score: 82.3 +/- 6.5 vs. 78.1 +/- 7.2, p < 0.05). Lower infection rates were noted in the delayed surgery group (7.5% vs. 12.5%, p < 0.05). Double-plate fixation provided better mechanical stability but resulted in higher soft tissue complication rates. Single-plate fixation preserved soft tissue integrity but had higher malunion and implant failure rates. Conclusions: Early surgery is associated with shorter healing time and better functional outcomes, but increased soft tissue complications require careful management. Delayed surgery offers a safer approach for soft tissue healing but may prolong functional recovery. While double-plate fixation ensures greater stability, it may increase soft tissue morbidity, whereas single-plate fixation reduces soft tissue complications but may compromise stability. A personalized surgical approach is recommended for optimal outcomes in pilon fracture management.Öğe Effect of Using Capsules with Waste Mineral Oil on Self-Healing of Long-Term Aged Hot-Mix Asphalt(Asce-Amer Soc Civil Engineers, 2023) Bakir, Esma; Yalcin, Erkut; Yilmaz, Mehmet; Kok, Baha Vural; Hernandez, Alvaro GarciaCapsules containing waste mineral oil can delay the maintenance of asphalt mixtures by preventing the spread of cracks. As a result of the encounter between the crack and capsule, the capsule breaks and releases the restorative material inside the crack area, resulting in healing. This experimental research demonstrated the rate at which oil is released from the capsules when the asphalt is subjected to cyclic loading and four different cures (24 h at 25 degrees C, 48 h at 25 degrees C, 24 h at 40 degrees C, and 48 h at 40 degrees C), and the capacity of asphalt to improve its inherent self-healing capacities in terms of cracks. In the study, the effects of capsule amount, curing time, and temperature on the mixtures were examined. Three-point bending fatigue tests and Fourier transform infrared spectroscopy (FTIR) tests were used in the study. It was determined that the capsules were broken and oil was released when cracks started to form in the hot-mix asphalt. The experiments showed that increasing the amount of capsules increased the oil release and the recovery rate, but decreased the mechanical performance by reducing the fatigue life. It was also found that the increase in curing time and temperature increased the recovery rate. Finally, the effects of capsule content and load characteristics on the healing index were defined by response surface method (RSM).Öğe Long- range ordered vertical III- nitride nanocylinder arrays via plasma- assisted atomic layer deposition(Royal Soc Chemistry, 2018) Haider, Ali; Deminskyi, Petro; Yilmaz, Mehmet; Elmabruk, Kholoud; Yilmaz, Ibrahim; Biyikli, NecmiIn this work, we demonstrate vertical GaN, AlN, and InN hollow nano-cylindrical arrays (HNCs) grown on Si substrates using anodized aluminum oxide (AAO) membrane templated low-temperature plasma-assisted atomic layer deposition (PA-ALD). III-Nitride HNCs have been characterized for their structural, chemical, surface, and optical properties. The material properties of nanostructured III-nitride materials have been compared with the thin-film counterparts which were also grown using PA-ALD. Our results revealed that long-range ordered arrays of III nitride HNCs were successfully integrated on Si substrates and possess hexagonal polycrystalline wurtzite crystalline structure. Such long-range ordered wafer-scale III-nitride nanostructures might be potentially used in piezotronic sensing, energy harvesting, resistive memory, flexible and wearable electronics, III-nitride photovoltaics, and (photo)catalysis.Öğe Pediatric Voluntary Habitual Hip Dislocation: Clinical Characteristics, Family Dynamics, and Long-Term Outcomes-A Retrospective Study(Mdpi, 2025) Yilmaz, Mehmet; Ulusoy, Ibrahim; Tantekin, Mehmet Firat; Guzel, Ismail; Kivrak, AybarsBackground/Objectives: Recurrent hip dislocations are a rare occurrence in pediatric patients. As there are few cases of voluntary habitual dislocation documented in the literature, there is a paucity of information available regarding its pathogenesis, risk factors, and classification. The prognosis for these patients is generally good. A long-term follow-up duration of two years was conducted to evaluate outcomes. Statistical analysis was performed to assess the impact of family structure and treatment approaches on outcomes. Methods: From January 2010 to December 2022, patients with voluntary habitual hip dislocation were retrospectively identified through the hospital information system. Data regarding demographic characteristics, clinical findings, and treatment outcomes were analyzed. A total of 13 patients (14 hips) met the inclusion criteria. Conservative treatment methods, including orthosis and family therapy, were applied. Statistical analysis was performed to assess the impact of family structure and treatment approaches on outcomes. Results: The mean age at diagnosis was 48.7 months, with 77% of cases being female. Posterior dislocation was observed in all cases, and no underlying bone pathology was detected on imaging. The prognosis for these patients is generally good. At the one-year follow-up, 85% of patients achieved a complete resolution of dislocations, increasing to 100% by the two-year follow-up. Patients from larger families demonstrated significantly slower recovery rates at the first- and sixth-month evaluations (p = 0.033 and p = 0.048, respectively), but outcomes were comparable by one year. A unique aspect of this study is the emphasis on family dynamics, which significantly influenced treatment adherence and recovery. Statistical analysis was performed to assess the impact of family structure and treatment approaches on outcomes. Conclusions: Voluntary habitual hip dislocation is a rare condition with good long-term outcomes under conservative management. This study highlights the importance of addressing family dynamics in the treatment plan, especially in larger families, where attention and psychological factors may play a significant role in delayed recovery.Öğe Ultrasound-Guided Percutaneous Release and Mini-Open Surgery in Carpal Tunnel Syndrome: A Comparison of Short- and Long-Term Outcomes(Mdpi, 2025) Ulusoy, Ibrahim; Yilmaz, Mehmet; Tantekin, Mehmet Firat; Guezel, Ismail; Kivrak, AybarsBackground and Objectives: The aim of this study was to compare the short- and long-term effectiveness of ultrasound-guided percutaneous release (CTR-US) and mini-open surgery in the treatment of carpal tunnel syndrome (CTS). Materials and Methods: A retrospective analysis was conducted on 172 patients who underwent surgical treatment for CTS between 2015 and 2020. The patients were divided into two groups: those who underwent CTR-US (Group A, n = 66) and those treated with mini-open surgery (Group B, n = 106). All patients were evaluated using the Boston Carpal Tunnel Questionnaire (BCTQ) and the Quick Disabilities of the Arm, Shoulder, and Hand (QDASH) scores before surgery and at 3 months, 6 months, 1 year, 2 years, and 5 years postoperatively. Electrophysiological and ultrasound findings were also compared. Statistical analyses were performed using t-tests, Mann-Whitney U tests, and Chi-square tests, with significance set at p < 0.05. Results: A total of 172 patients who met the study criteria were included. Among the participants, 112 were women and 60 were men. The mean age was calculated as 61 years for female patients and 54 years for male patients. No significant differences were found between the groups in terms of age, gender, laterality, and disease duration. Both groups demonstrated significant improvements in BCTQ and QDASH scores at all postoperative time points compared to preoperative scores (p < 0.001). The CTR-US group showed advantages in shorter treatment duration (p < 0.001), lower cost (p < 0.05), and faster recovery time. Electrophysiological evaluations revealed faster improvements in distal motor latency (DML) and sensory conduction velocity (SCV) in the CTR-US group (p < 0.05). Ultrasound assessments indicated that both methods achieved effective release of the transverse carpal ligament. No significant differences were observed between the groups in long-term questionnaire scores. Conclusion: CTR-US offers advantages such as shorter treatment duration, lower cost, and faster recovery due to its minimally invasive nature. Consistent with the literature, CTR-US provided faster recovery and improved patient comfort. However, mini-open surgery remains a reliable alternative with long-term symptom control and low complication rates. Our study found that both methods are effective, but CTR-US stands out for its esthetic and functional advantages.
