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Effects of 27.12 MHz short-waves on fibroblast cell culture and K-562 and ML-1 neoplastic cell lines
No full textObjectives: This study aims to assess the effect of short-wave therapy (SWT) devices emitting radiofrequency (RF) waves on the proliferation rates of fibroblasts and neoplastic cells. Patients and methods: In this experimental study, fibroblasts cultured from sternal mesenchymal cells of a bypass surgery patient were enriched using stem cell techniques between January 2004 and February 2004. The K-562 and ML-1 neoplastic cell lines were prepared for analysis. Fibroblasts and neoplastic cell lines were exposed to 27.12 MHz short-waves at different energy levels. Continuous short-wave (CSW) was applied at 200 W power, and pulsed short-wave (PSW) was applied at three different mean powers: 1.6 W (PSW-1), 14.9 W (PSW-2), and 54 W (PSW-3). Fibroblast colonies were counted using inverted microscopy, and neoplastic cell proliferation rates were measured using enzyme-linked immunosorbent assay. All short-wave-exposed cells were compared to the controls with no exposure. Results: Short-waves increased the number of fibroblast colonies three- to four-fold across all power levels (1.6 W, 14.9 W, 54 W, and 200 W). They significantly increased K-562 cell proliferation only at 1.6 W and 54 W power levels (p=0.044 and p=0.004, respectively). In contrast, there was no significant increase in ML-1 cell proliferation at any power level tested (p>0.05). Conclusion: This study found that short-waves can boost fibroblast proliferation, potentially aiding tendon healing. However, it also had unpredictable proliferative effects on K-562 cells, as an inconsistent correlation with energy levels was observed. The ML-1 cells were not affected by short-waves, suggesting variability in tumor biology. These findings emphasize the need for precise dosing and personalized treatment strategies when using SWT devices
A Study on Methods to Increase the Ductility of Timber Beams
No full textTimber has many advantages in its nature like high strength over density ratio. Due to this, timber isgetting more common in construction works in general, especially in seismic regions. However, there are someconcerns about its ductility. Although it behaves ductile under compression, brittle failure occurs under tension.Literature knowledge on this topic is also limited with a few results. To clarify this, the ductility of timber beamwas studied by means of material, elemental and structural ductility. Methods to increase the ductility of timberbeams were evaluated, and effectiveness of the methods was investigated using complete nonlinear momentcurvatureanalysis. As a result of the study, various conclusion was highlighted regarding the methods to increaseductility of timber beams and recommendations were made.</p
Treatment Adherence in a Large Cohort of Turkish Multiple Sclerosis Population
No full textObjectives: This study aimed to evaluate adherence to disease-modifying therapies (DMTs) among patients with multiple sclerosis (MS) and to identify factors influencing compliance, based on perceptions and preferences of both patients and neurologists. Methods: Questionnaires were designed by a team of experts, including MS specialists, psychologists, and statisticians, to capture data on treatment adherence and related factors. A total of 1021 MS patients and their neurologists participated. Patients' adherence to oral, injectable, and infusion DMTs was assessed alongside demographic and disease-related characteristics. Results: The study included 1021 MS patients with a mean age of 35.69 ± 9.07 years. Infusion therapies demonstrated the highest adherence rates (96.6%). Among all patients, 78.9% maintained treatment without interruption, while 56.7% of those who interrupted therapy informed their physicians. Patients with a disease duration of less than one year or more than 10 years exhibited lower rates of treatment interruption compared to those with a disease duration of 1–10 years (p = 0.032). In the injectable DMT group, significant differences in adherence were noted (p < 0.001). The lowest interruption rate (13.5%) was seen in patients with a disease duration of less than one year, whereas interruption rates were markedly higher (83%) in those with a duration exceeding 16 years. Conclusion: Improving adherence requires a patient-centered, collaborative approach emphasizing shared decision-making between physicians and patients. Addressing factors that contribute to non-compliance is essential for optimizing treatment outcomes and enhancing long-term disease management in MS
Üniversite kampüs girişi uçucu organik bileşik seviyeleri ve mesleki maruziyetin tahmin edilmesi
No full textUçucu Organik Bileşikler (UOB’ler), atmosfer kimyası ve insan sağlığını önemli ölçüde etkiler. UOB’lerin en önemli kaynakları solvent kullanımı, fosil yakıtlar, araç egzozları ve sigaradır. Çalışmada, araç egzozlarından kaynaklanan UOB’lerin kampüs ana giriş kapılarında dış hava ve iç ortamdaki konsantrasyonlarının belirlenmesi ve tespit edilen UOB’lerin solunması ile giriş kapılarında görevli güvenlik personelinde oluşturacağı sağlık etkilerinin değerlendirilmesi amaçlanmıştır. Örnekleme süresi, giriş kapılarında görevli personelin çalışma süreleri dikkate alınarak belirlenmiştir. Örnekleme noktalarındaki ortalama UOB konsantrasyonları Doğu Kapısı’nda, iç ortamda gece 11.9 µg/m3, gündüz 9.6 µg/m3, dış havada gece 6.8 µg/m3 gündüz 8.8 µg/m3 olarak tespit edilmiştir. Batı Kapısı’nda ortalama UOB konsantrasyonları iç ortamda gece 12.3 µg/m3, gündüz 16.4 µg/m3, dış havada gece 6.3 µg/m3, gündüz 9.3 µg/m3 olarak tespit edilmiştir. Yaşam boyu UOB’lere maruz kalmanın yol açtığı kanserojen risk genel olarak kabul edilebilir risk seviyesi olan 1.0×10−6'nın üzerindedir. Hem iç ortam hem de dış havadaki UOB’ler için kronik toksik etki değeri kabul edilebilir düzeydedir (HQ<1)</p
Parameter estimation and speed control of real DC motor with low resolution encoder
No full textIn this study, parameter estimation and speed control of a real brushed Direct Current (DC) motor are conducted. For parameter estimation, a popular iterative optimization algorithm, namely Particle Swarm Optimization (PSO), is used. The motor is assumed to have first-order dynamics, which are a reasonable assumption for most DC motors in practical use and two parameters representing the mathematical model of the model are estimated. The step response of the openloop system is used as data for the parameter estimation algorithm. Using the estimated parameters simulations are conducted for closed loop Proportional-Integral (PI) control. Experiments on a real brushed DC motor are also conducted for closed-loop PI control of rotor speed. Speed of motor is measured using single channel low resolution optical encoder. Due to low resolution of speed sensor, precision of the whole system is limited and oscillations are observed in speed output measured. Controlling low-resolution sensor systems is important for two reasons. First, cost of the system is quite low compared with high resolution sensors. Second, for some real systems, especially with small physical dimensions, high resolution sensors may not be available at all. So, one of the important aspects of this study is to analyze low resolution sensor systems. As a closed loop controller, simple but popular PI controller is chosen to show the compatibility of experimental results with simulations. Oscillations around reference value are less than 10% in both simulations and experiment results. In real experiments, oscillations are slightly higher due to low resolution of encoder which is expected due to quantization error. Several parameters are used for controller and results are reported and discussed in corresponding sections
Cognitive reserve and aging: Impacts on theory of mind and executive functions
No full textAim: This study examines the effects of cognitive reserve (CR) on Executive Functions (EF) and Theory of Mind (ToM). While CR is suggested to mitigate age-related cognitive decline, its relationship with social cognition remains limited and inconsistent in the literature. It was hypothesized that the effect of CR on ToM might be indirect, mediated by EF and working memory. Methods: 225 cognitively healthy participants were included. CR was measured with the Cognitive Reserve Index Questionnaire, EF with verbal fluency and the Stroop Test, and WM using digit span tasks. Structural Equation Modeling was used to analyze the relationships among CR, EF, WM, and SC, controlling for age and gender. Results: CR was significantly associated with both RMET and FPRT performances. Mediation analysis revealed the direct effects of CR on RMET performance, while the effects on FPRT performance were mediated by executive functions. WM had a partial mediating effect on EF and ToM, but did not directly influence FPRT. Education was most strongly associated with RMET performance, while leisure activities were linked to FPRT performance. Conclusion: These findings suggest that CR indirectly supports ToM by enhancing EF and highlight the importance of interventions aimed at strengthening executive control to support social cognition in aging