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    Yinelemeli Sinir Ağlarıyla GNSS Verilerinde Birleştirilmiş ve Bireysel Model Karşılaştırılması

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    Bu çalışmada, derin öğrenme algoritmalarından olan Uzun Kısa Süreli Bellek (LSTM) ve Geçitli Tekrarlayan Birim (GRU) ile GNSS istasyon verilerinin Kuzey, Doğu ve Düşey bileşenleri için ileriye dönük ayrı ayrı kestirimler yapılarak, istasyon bazında eğitilen modeller ve tüm istasyon verilerinin birlikte eğitildiği tek model performansları karşılaştırılarak model yönetiminin performanslar üzerine etkisi incelenmiştir. Her bir GNSS istasyonu için ayrı modellerin kullanıldığı Senaryo I ve toplu verilerle tek bir birleşik modelin kullanıldığı Senaryo II için model performansı, ortalama karekök hata (RMSE), ortalama mutlak hata (MAE) ve belirleme katsayısı (R²) kullanılarak Doğu, Kuzey ve Düşey bileşenler için değerlendirilmiştir. GRU algoritmasıyla Doğu bileşen için ortalama RMSE değeri Senaryo I ve II için sırayla 1.68 ve 1.67 mm, MAE değeri 1.24 ve 1.27 mm; Kuzey bileşen için RMSE değeri 1.70 ve 1.72 ve MAE değeri 1.32 ve 1.33 mm, Düşey bileşen için RMSE 4.50 ve 4.43 mm ve MAE 3.58 ve 3.50 mm’dir. Bulgular tek model yaklaşımının model yönetimini basitleştirilerek özellikle daha homojen veri özelliklerine sahip bölgelerde, ayrı ayrı eğitilmiş modellerle karşılaştırılabilir doğruluk elde edebileceğini göstermektedir.</p

    Thermodynamic binding properties of a novel umami octapeptide K1ADEDSLA8 and its mutational variants p.A2G, p.D5E, and p.A2G + p.D5E (BMP) in complex with the umami receptor hT1R1/hT1R3

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    Umami taste properties of a novel octameric peptide K1ADEDSLA8 and its mutants p.A2G, p.D5E, and BMP (KGDEESLA, beef meaty peptide) were assessed by molecular docking, and molecular dynamics (MD) (>1 μsec), MM-PBSA, and Mutational Affinity Prediction (MAP) methods. 3D-structure of the human umami taste receptor (hT1R1/hT1R3) was homology modeled and refined MD. Docking studies yielded three primary binding sites (PBS) for K1ADEDSLA8 and BMP, one on hT1R1 and two on hT1R3. Upto 1200 nsec of MD studies revealed that K1ADEDSLA8 binds only to Venus Flytrap Domains (VFTD) region of hT1R1 at high affinity (ΔGo = −11.94 kcal/mol), while BMP does not exhibit affinity towards hT1R1/hT1R3 in the absence of glutamate. MAP analysis for p.A2G (ΔGo = −7.77 kcal/mol) and p.D5E (ΔGo = −2.88 kcal/mol) strongly suggest that A2 and D5 in KA2DED5SLA increase the affinity and specificity of binding, posing great potential for the development of a novel umami peptide in future studies

    IDENTIFICATION OF POTENTIAL EPITOPES FOR THE DEVELOPMENT OF A PEPTIDEBASED VACCINE AGAINST NIPAH VIRUS THROUGH BIOINFORMATICS APPROACHES

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    Nipah virus is a highly contagious pathogen that causes severe infections in both humans andanimals, yet no specific vaccine has been developed to date. To address this gap, our studyutilized bioinformatics approaches to identify potential vaccine targets, aiming to facilitate thedevelopment of an effective vaccine. The Füzyon protein (F), attachment protein (G), andMatriks protein (M), known for their critical roles in viral entry, replication, and assembly, wereselected as primary targets for analysis.Our research was conducted in two phases. In the first phase, we thoroughly evaluated thepotential of F, G, and M Proteinler as vaccine candidates. In the second phase, we investigatedwhether epitopes derived from these Proteinlers could serve as viable components in vaccinedevelopment, employing various bioinformatics tools.The analysis revealed that the F, G, and M Proteinler, due to their physical and chemicalproperties, were not suitable as direct vaccine candidates. However, specific epitopes derivedfrom these proteins demonstrated characteristics that make them promising vaccinecomponents. Among these, the G protein-derived FLLKNKIWCI epitope showed the highestantigenicity score (2.0045). Nevertheless, its positive hydrophobicity score (0.07) precluded itsinclusion in iMODS and MD simulation studies. Instead, two epitopes RRNNAIAFNL fromthe G protein and LEFRRNNAIAFNLL from the M protein were identified as strongcandidates due to their favorable physicochemical attributes.It has also been determined that these epitopes, in addition to their advantages such as beingnon-toxic, highly soluble in water, non-allergenic to humans, and possessing high antigenicityscores, have average IC50 scores, low percentile ranks, and an adequate number of proteasecleavage sites.In summary, our findings provide valuable insights into the development of peptide-basedvaccines targeting the Nipah virus. However, as these conclusions are based on in silico analyses,experimental validation is essential to confirm the efficacy and functionality of the proposedepitopes</p

    Enhanced electrochemical performance of fumed silica-based gel electrolyte with polypyrrole for valve-regulated lead-acid batteries

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    Abstract: In this study, chemically synthesized polypyrrole, a conductive polymer, was introduced for the first time to enhance the electrical conductivity and charge transfer characteristics of fumed silica-based gel electrolytes in valve-regulated lead-acid batteries. The optimization of key parameters—polypyrrole content, agitation time, and stirring rate—was carried out using electrochemical techniques, including cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel polarization. The optimal performance of the gel system was achieved with 0.8 wt% polypyrrole, 60 min of agitation time, and a stirring rate of 500 rpm. Battery performance was evaluated through charge–discharge tests at a current density of 5 mA g⁻1. The polypyrrole gel electrolyte exhibited a specific capacity of (50.98 mAh g⁻1), superior to the fumed silica gel (44.01 mAh g⁻1) and sulfuric acid (18.83 mAh g⁻1) electrolytes. Long-term cycling tests at 7 mA g⁻1 revealed an 86% capacity retention after 100 cycles, indicating excellent stability. Even after 1000 cycles, a capacity retention of 67% was maintained, demonstrating good long-term durability. The enhancement in performance was attributed to the increased electrical conductivity and reduced charge transfer resistance due to polypyrrole addition. These results demonstrated the potential of polypyrrole to improve valve regulated lead acid battery performance, offering better efficiency and longevity for energy storage applications

    Orta Büyüklükteki Uçakların İniş ve Kalkış Döngüsü İçin Bir Değişkenlik Analizi

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    İniş ve Kalkış döngüsü, yakıt tüketimini azaltma, emisyonları düşürme ve havaalanı ortamlarında operasyonel verimliliği artırma gibi hedefler üzerinde önemli bir etkiye sahip olan avionik alanında kritik bir bileşendir. Döngü içerisindeki süreçlerin değişkenliği anlamak ve yönetmek, sivil havacılık operasyonlarında daha iyi performans elde ederek belirtilen hedeflerin korunmasını ve çevresel standartların karşılanmasını vaat etmektedir. Bu çalışma, orta boyutlu uçaklar için döngü sürelerindeki değişkenlik analizini yaparak iniş ve kalkış döngü operasyonlarının sürelerini analiz etmeyi amaçlamaktadır. İlk olarak, veri setinin dağılımını kontrol etmek için Shapiro-Wilk testi ile bir normallik analizi uygulanmıştır. Ardından, iniş ve kalkış döngüsü operasyonlarındaki değişkenliği izlemek amacıyla bir � − nicel kontrol diyagramı uygulanmıştır. Ayrıca, kontrol diyagramının süreç değişimlerine duyarlılığını değerlendirmek için ortalama koşum süresi analizleri gerçekleştirilmiştir. Sonuçlar ve analizlere dayanarak, önerilen metodolojinin iniş ve kalkış döngüsü operasyonlarının istikrarını takip etmek ve iyileştirmek için sağlam bir çerçeve sunduğu, sivil havacılık alanındaki süreç performanslaraının optimize edilmesine ve çevresel etkinin azaltılmasına katkı sağladığı düşünülmektedir.The Landing and Take-Off (LTO) cycle is a critical component in avionics, which has a crucial effect on the objectives, such as decreasing fuel consumption, emissions, and increasing operational efficiency in airport environments. Understanding and managing the variability within LTO processes promise to maintain the mentioned objectives by achieving better performance in civil avionic operations together with fulfilling environmental standards. This study conducts a variability analysis of the LTO cycle for medium sized airplanes to analysis the times of the LTO operations. A normality analysis using the Shapiro Wilk test is first applied to check the distribution of the dataset. Then, an �- variable control chart (VCC) is applied to monitor the variability in the operations of LTO cycle. Furthermore, an Average Run Length (ARL) analysis is conducted to evaluate the sensitivity of the control chart to process shifts. Based on the results and analysis, it is believed that the proposed methodology provides a robust framework for monitoring and improving the stability of LTO cycle operations, contributing to the optimization of process performance in civil aviation and the reduction of environmental impact

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