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Morphological impact on the supercapacitive performance of nanostructured ZnO electrodes
No full textThis study investigated the influence of the ZnO morphology on the energy storage capacity of symmetric supercapacitor devices, focusing on the defect centers present in the materials due to morpho-structural differences. Thus, ZnOs with five different morphologies were synthesized with varying methods in which the nanoparticles have the form of flowers, bullets, pyramids, hexagons, and rods. All materials were thoroughly characterized by scanning/transmission electron microscopy, X-ray diffraction, and spectroscopic techniques like photoluminescence, UV-Vis, Raman, and electron paramagnetic resonance spectroscopy. Subsequently, the ZnO-based materials were assembled in symmetric supercapacitor devices to test their energy storage capabilities. The ZnO with nanorod and hexagonal morphologies showed the best specific capacity (180 and 142 F/g), energy density (25 and 19 Wh/kg), and power density (211 and 252 kW/kg) values. The importance of the defect centers in the materials was highlighted, where the ratio between the Zn and O vacancies, evidenced by EPR spectroscopy, plays a crucial role in the ZnO materials' energy storage capacity. The Raman results support the proposed model, which underlines the importance of oxygen vacancies. In contrast, BET measurements show that the specific surface area of the morphologically distinct ZnO materials does not change drastically, validating the importance of the defect centers in the materials. A so-called "bottle-neck"effect is proposed to describe the relation between the paramagnetic vacancies and the electric properties of the materials
İLERI EVRE KÜÇÜK HÜCRELI OLMAYAN AKCIĞER KANSERI’NDE İKINCI BASAMAK NIVOLUMAB ALAN HASTALARDA İSKOÇ İNFLAMATUAR PROGNOSTIK SKORUNUN (SIPS) PROGNOSTIK ÖNEMI
No full textAmaç: Çalışmamızın amacı, Scottish Inflammatory Prognostic Score (SIPS)’un ileri evre küçük hücreli dışı akciğer kanseri (KHDAK) hastalarında 2. basamak Nivolumab tedavisi için prognostik ve prediktif bir biyobelirteç olup olmadığınıdeğerlendirmektir.Gereç-Yöntem: Şubat 2009 – Aralık 2024 tarihleri arasında ileri evre KHDAK tanısı almış ve 2. basamak tedavide Nivolumab kullanmış toplam 121 hasta çalışmaya dahil edilmiştir. SIPS skoru, sistemik inflamatuvar yanıtı temel alan basit bir prognostik göstergedir. Bu skorda başlangıç albumin düzeyinin <35 g/L olması veya nötrofil sayısının >=7,5 × 10⁹/L bulunması durumunda her biri için 1 puan verilir. Toplam skor 0, 1 veya 2 olacak şekilde üç kategorili sınıflama elde edilir: SIPS=0 (favorable), SIPS=1 (intermediate), SIPS=2 (poor). Hastalar bu sınıflamaya göre gruplandırılmış ve genel sağkalım (OS) ile progresyonsuz sağkalım (PFS) süreleri Kaplan-Meier yöntemiyle karşılaştırılmıştır.Bulgular: Hastaların medyan tanı yaşı 64 idi. Hastaların %54,5’i non-skuamöz, %45,5’i skuamöz histolojiye sahipti. Katılımcıların %91,7’si erkek, %8,3’ü kadındı. ECOG performans skoru hastaların %65,3’ünde 1, %32,2’sinde 0, %2,5’inde ise 2 olarak bulundu. Hastaların %56,2’sindemetastaz tanı anında (senkronik) mevcutken, %43,8’inde takip sırasında (metakronik) gelişmişti. Beyin metastazı %21,5 oranında izlendi. SIPS skoru dağılımında favorable %68,6, intermediate %28,1 ve poor %3,3 oranında idi.SIPS skoruna göre hastaların %68,6’sı favorable, %28,1’i intermediate ve %3,3’ü poor grupta yer almaktaydı. Sağkalım analizinde; favorable grupta medyan OS 14 ay, intermediate grupta 5 ay ve poor grupta 1 ay olarak bulundu.PFS açısından medyan değerler sırasıyla 6 ay, 3 ay ve 1 ay idi. Tüm kohort için medyan OS 11 ay (%95 GA: 6,5–15,5), medyan PFS ise 5 ay (%95 GA: 3,4–6,6) olarak hesaplandı. Kaplan-Meier analizine göre, SIPS grupları arasında OS (p<0.001) açısından istatistiksel olarak anlamlıfarklılık saptandı.Sonuç: Bu çalışma, SIPS skorunun OS için güçlü bir prognostik gösterge olduğunu ortaya koymaktadır. Ancak bu bulguların doğrulanabilmesi için prospektif, geniş örneklemli ve çok merkezli klinik çalışmalara ihtiyaç vardır.</p
Comparative Analysis of FOPID-Based Electric Vehicle Speed Control Using Heuristic Optimization Algorithms
No full textIn this study, the parameters of a Fractional Order PID (FOPID) controller used for the speedcontrol of an electric vehicle (EV) were optimized using five different heuristic optimizationalgorithms: Genetic Algorithm (GA), Grey Wolf Optimization (GWO), Harris HawksOptimization (HHO), Particle Swarm Optimization (PSO), and Salp Swarm Algorithm (SSA).The control system was modeled in the MATLAB/Simulink environment, and the speedcontrol performance was tested in a closed-loop configuration. In the optimization process,performance criteria such as percentage overshoot (%OS), settling time (), rise time (),and mean squared error (MSE) were used. The results obtained with each algorithm wereevaluated comparatively in terms of the specified performance criteria. The results revealedthat the performance of different algorithms in FOPID parameter optimization variesdepending on the application and performance criteria. The findings provide an importantreference for the selection of appropriate algorithms to enhance speed control performance inelectric vehicles.</p
The mediating effect of E-health literacy on health belief model-based vaccine attitudes among parents in Türkiye: a cross-sectional study
No full textBackgroundVaccination constitutes one of the most efficacious public health interventions, preventing millions of fatalities annually. Nevertheless, vaccine hesitancy persists as a significant challenge, particularly among parents. The dissemination of misinformation via the internet, notably through social media platforms, has contributed to the escalation of vaccine hesitancy. E-health literacy, defined as the capacity to locate and utilize online health information, possesses the potential to influence vaccine attitudes. This study aimed to investigate the relationships among education level, e-health literacy and childhood vaccination attitude among parents.MethodsThe cross-sectional study design was used. This study was guided by STROBE. Convenience sampling recruited 699 parents in T & uuml;rkiye with an online survey. The data tools used in the study were the parental information form, Public Attitudes Towards Vaccination - Health Belief Model Scale (PAV-HBM) and E-health Literacy Scale. The collected data were analyzed using SPSS version 25.0, and the PROCESS macro in SPSS was employed to estimate path coefficients and assess the adequacy of the model. The mediating effects of e-health literacy on the pathway in which education level of the parents affects childhood vaccination were verified using model 4 of the SPSS PROCESS macro proposed by Hayes.ResultsThe E-Health literacy had significantly mediate the relationship between educational level and the PAVS-HBM sub-dimensions of perceived susceptibility (B = 0.044, 95% CI= [0.023-0.071]), severity (B = 0.045, 95% CI= [0.023-0.070]), benefits (B = 0.054, 95% CI= [0.029-0.086]), and health motivation (B = 0.045, 95% CI= [0.023-0.071]). However, e-health literacy did not mediate the relationship between education level and perceived barriers (B = - 0.013, 95% CI= [- 0.049- -0.023]).ConclusionThe results revealed that education level among parents affect all vaccine attitudes without perceived barriers and the level of e-health literacy mediates this relationship. Therefore, health communication strategies, such as the development of e-health literacy by health authorities and the provision of reliable information about vaccination on digital platforms, including social media, may have potential benefits in promoting positive vaccination attitudes in the community.Clinical trial numberNot applicable
Metaheuristics Algorithm-Based Optimization for High Conductivity and Hardness CuNi<sub>2</sub>Si<sub>1</sub> Alloy
No full textThe optimization of CuNi2Si1 alloy's mechanical and electrical properties was achieved through a combination of experimental approaches and metaheuristic algorithms. Optimizing hardness and electrical conductivity through a variation in aging temperature (450-600 degrees C) and aging duration (1-420 min) was taken under consideration in the present work. Cold rolling with 50% strain after solution annealing aided in microstructure refinement and accelerated Ni2Si precipitates' development, and property improvement increased. Optimum temperature and holding period were 450 degrees C and 30 min, respectively, with 266 HV and 13 MS/m and 167 HV and 11.2 MS/m for non-deformed samples, respectively. SPBO, genetic algorithm (GA), and particle swarm optimization (PSO) metaheuristic algorithms were considered, and SPBO exhibited the best prediction accuracy. SPBO predicted 450 degrees C for 61.75 min, and experimental testing exhibited 267 HV and 14 MS/m, respectively. Polynomial regressions with 0.98 and 0.96 values for R-2 confirmed these values' accuracy. According to this work, computational optimization proves effective in optimizing development and property tailoring for application in industries including aerospace and electrical engineering
Influence of TiO2 nanofillers on the dielectric response of proton conducting sulfonated polyether ether ketone/ionic liquid electrolytes
No full textThe impacts of titanium dioxide (TiO2) filler on the dielectric response of ionic liquid (IL)-doped sulfonated polyether ether ketone (SPEEK) electrolytes have been investigated. Neat SPEEK, IL-doped SPEEK (SPIL), and IL-doped TiO2-filled SPEEK (SPILTO) composite membranes were prepared with the conventional solution cast method and characterized by various techniques. Fourier-transform infrared (FTIR) spectroscopy analyses confirmed the sulfonation and also showed the dispersion of imidazole and TiO2. Thermogravimetric analysis (TGA) results showed that all composites are thermally stable to comply with electrochemical requirements up to nearly 150 °C. SPILTO-1 composite exhibited a storage modulus of 74 MPa and a glass transition temperature (Tg) of 140 °C. More than 1 wt% TiO2 fillers resulted in heterogeneous membrane surfaces for SPILTO samples. The SPILTO-1 electrolyte showed a maximum conductivity (σ) of 8.1 × 10−4 S/cm and a significant proton transport potential even in completely anhydrous conditions. Charge carrier migration and accumulations resulted in high dielectric constant (ε′) values and major polarization, particularly at lower frequencies. The dielectric permittivity of the SPEEK matrix increased dramatically with the addition of IL and TiO2 fillers. The substantial ε′ values of SPILTO-1 showed that the combination of IL and TiO2 increases both the number of free mobile ions and the charge stored in the electrolytes. In the relaxation behaviors, the shortest relaxation time (τ) of 1.34 μs at 300 K corresponded to the highest conductivity of SPILTO-1 electrolyte
L-Argininin diyet kaynaklı hiperkolesterolemide lipid profillerini, oksidatif stresi ve PON1 aktivitesini düzenlemesi
No full textYarı esansiyel bir amino asit olan LArginin, oksidatif stresi ve lipit metabolizmasını düzenleyen antioksidan özellikler sergiler. Ancak, hiperkolesterolemik koşullarda lipit profilleri ve PON1 aktivitesi üzerindeki etkisi henüz yeterince araştırılmamıştır. Bu çalışma, LArginin'in hiperkolesterolemik sıçan modelinde oksidatif stresi azaltma ve lipit profillerini ve PON1 aktivitesini iyileştirme potansiyelini değerlendirmeyi amaçlamaktadır.Otuz altı yetişkin erkek Wistar albino sıçan rastgele dört eşit gruba ayrıldı: Kontrol (C), LArginin (LA), Hiperkolesterolemi (HC) ve Hiperkolesterolemi + LArginin (HC + LA). Hiperkolesterolemi, sekiz hafta boyunca %3 kolesterol içeren bir diyetle oluşturulurken, LArginin içme suyunda %3 LArginin ile takviye edildi.HC grubunda PON1 aktivitesi, MDA seviyeleri, ATI ve PON1/HDL oranının yüksek olduğu bulundu. HC+LA grubunda LA takviyesi, HC grubuna kıyasla bu belirteçlerde bir azalmaya yol açmıştır. Ek olarak, LA grubu serum TG, VLDL ve PON1 seviyelerinde kontrollere kıyasla önemli bir artış göstermiştir. Özellikle, PON1 ve MDA seviyeleri arasında güçlü bir negatif korelasyon gözlenmiş ve bu da LA'nın hiperkolesterolemik durumlardaki potansiyel antioksidan rolünü vurgulamıştır. Kronik oral LA uygulaması, PON1 ve HDL seviyelerini etkilemeden hiperkolesterolemide ATI, serum LDL ve oksidatif stresi azaltır. Histopatolojik bulgular, LA'nın vasküler yapısal değişiklikleri hafiflettiğini ve ateroskleroza karşı koruyucu bir rol oynadığını göstermektedir. Bu sonuçlar, terapötik bir ajan olarak potansiyelini desteklemekte ve altta yatan mekanizmaları ve klinik önemini aydınlatmak için daha fazla çalışma yapılmasını gerektirmektedir. LArginine, a semiessential amino acid, exhibits antioxidant properties, modulating oxidative stress and lipid metabolism. However, its impact on lipid profiles and PON1 activity in hypercholesterolemic conditions remains underexplored. This study aims to evaluate the potential of LArginine in mitigating oxidative stress and improving lipid profiles and PON1 activity in hypercholesterolemic rat model. Thirtysix adult male Wistar albino rats were randomly assigned to four equal groups: Control (C), LArginine (LA), Hypercholesterolemia (HC), and Hypercholesterolemia + LArginine (HC+LA). Hypercholesterolemia was induced with a 3% cholesterol diet for eight weeks, while LArginine was supplemented via 3% LArginine in drinking water. PON1 activity, MDA levels, ATI, and the PON1/HDL ratio in the HC group was found to be elevated. LArginine supplementation in the HC+LA group led to a reduction in these markers compared to the HC group. Additionally, the LA group exhibited a significant increase in serum TG, VLDL, and PON1 levels compared to controls. Notably, a strong negative correlation was observed between PON1 and MDA levels, highlighting the potential antioxidant role of LArginine in hypercholesterolemic conditions. Chronic oral LArginine administration reduces ATI, serum LDL, and oxidative stress in hypercholesterolemia without affecting PON1 and HDL levels. Histopathological findings indicate that LArginine mitigates vascular structural alterations, suggesting a protective role against atherosclerosis. These results support its potential as a therapeutic agent, warranting further studies to elucidate underlying mechanisms and clinical relevance.</p
Ahîzâde Abdülhalim Efendi'nin "Mesâilü Tercihi'l-Beyyinât" adlı eserinin tahkik ve tahlili
No full textExpert opinion on clinical presentation, diagnosis, and treatment of infantile-onset Pompe disease: a Delphi study in Türkiye
No full textBackground/aim: Pompe disease (acid maltase deficiency, glycogen storage disease type II, OMIM #606800) is an autosomal recessive disorder characterized by lysosomal acid-α-glucosidase deficiency. The infantile-onset type of the disease is mainly characterized by cardiomegaly, hypotonia, and a high mortality rate. This study aimed to create a national consensus about infantile-onset Pompe disease (IOPD) to raise awareness among clinicians and standardize diagnosis and treatment approaches in Türkiye. Materials and methods: The Gazi University Division of Metabolic Diseases and Nutrition developed this expert opinion consensus and expanded it to include metabolism specialists across Türkiye. A systematic literature review was performed, and the Delphi method was used to evaluate the results. Results: Seventeen conclusive questions were produced about clinical presentation, diagnosis, and treatment, and 14 reached a consensus. Consensus was reached that general hypotonia is one of the most important findings, and agreement was also achieved on the starting dose of treatment for presymptomatic patients. The contributors agreed that gene therapy is a good treatment option for IOPD in the future. Conclusion: The topics related to this consensus will help physicians in Türkiye and elsewhere with high incidence rates of IOPD, especially regarding diagnosis and treatment decisions