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Dynamic modeling of a compressed natural gas refueling station and multi-objective optimization via gray relational analysis method
No full textCompressed natural gas (CNG) refueling stations operate under highly dynamic thermodynamic conditions, requiring accurate modeling and optimization to ensure efficient performance. In this study, a dynamic simulation model of a CNG station was developed using MATLAB-SIMULINK, including detailed subsystems for multi-stage compression, cascade storage, and vehicle tank filling. Real gas effects were incorporated to improve prediction accuracy of the pressure, temperature, and mass flow rate variations during fast filling. The model was validated against experimental data, showing good agreement in both pressure rise and flow rate evolution. A two-stage multi-objective optimization approach was applied using Taguchi experimental design and gray relational analysis (GRA). In the first stage, storage pressures were optimized to maximize the number of vehicles filled and gas mass delivered, while minimizing compressor-specific work. The second stage focused on optimizing the volume distribution among the low, medium, and high-pressure tanks. The combined optimization led to a 12.33% reduction in compressor-specific energy consumption with minimal change in refueling throughput. These results highlight the critical influence of pressure levels and volume ratios in cascade storage systems on station performance. The presented methodology provides a systematic framework for the analysis and optimization of transient operating conditions in CNG infrastructure
The joint involvement pattern of granulomatous polangiitis changed? Multicenter study
No full textObjectivesGranulomatosis with polyangiitis (GPA) formerly Wegener's granulomatosis is a type of anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV) typically associated with necrotizing, granulomatous inflammation. Musculoskeletal manifestations have been described in 40-65% of patients. Arthritis usually occurs as large, single and asymmetric joint involvement, but rarely symmetrical small joint involvement may also occur. We present 56 cases whose initial presentation was mostly symmetrical and polyarthritis, which caused a significant diagnostic delay.MethodsFifty-six patients who presented with inflammatory arthritis in the last 3 years and were diagnosed with GPA as the final diagnosis were included in the study. One hundred patients, diagnosed as GPA, with a similar age-sex ratio of 1:2 from each center were included as the control group.ResultsPolyarthritis was present in 32 (57.1%) patients, oligoarthritis was present in 21 (37.5%) patients and monoarthritis was present in three (5.4%) patients. The most commonly involved joints were wrist in 37 (66.1%) patients, ankle in 30 (53.6%) patients, metacarpophalangeal joint in 25 (44.6%) patients, knee in 23 (41.1%) patients, shoulder in 22 (39.3%) patients, elbow in 18 (33.9%) patients, hip in three (5.4%) patients and temporomandibular joint in one (1.8%) patient.ConclusionAlthough the typical joint involvement of GPA has been reported as lower extremity monoarthritis-oligoarthritis in the large series, our study demonstrates that symmetry and polyarthritis may be a more frequent presenting feature than previously recognized. It is important that joint involvement patterns in larger GPA series are reported in detail in order to compare our results.Key Points:center dot This study is important because it shows in detail which joints are affected and the pattern of involvement in cases of GPA with arthritis.center dot Diagnosis may be delayed in cases of GPA presenting with arthritis.center dot Symmetric, and polyarthritis involvement may be seen significantly more frequently in GPA cases.ConclusionAlthough the typical joint involvement of GPA has been reported as lower extremity monoarthritis-oligoarthritis in the large series, our study demonstrates that symmetry and polyarthritis may be a more frequent presenting feature than previously recognized. It is important that joint involvement patterns in larger GPA series are reported in detail in order to compare our results.Key Points:center dot This study is important because it shows in detail which joints are affected and the pattern of involvement in cases of GPA with arthritis.center dot Diagnosis may be delayed in cases of GPA presenting with arthritis.center dot Symmetric, and polyarthritis involvement may be seen significantly more frequently in GPA cases
Economic life of Mecca during the Mamluk period
No full textBu tez, Memlükler Dönemi’nde Mekke’nin ekonomik yapısını, özellikle ticaret ekseninde incelemektedir. Mekke, hac ibadeti sayesinde büyük bir ticari hareketlilik yaşamış ve uluslararası ticaret yollarının stratejik bir durağı olmuştur. Çalışmada, Memlükler’in Mekke ticaretine sağladığı katkılar, ticari düzenlemeler ve şehrin ekonomik canlılığı üzerindeki etkileri değerlendirilmiştir. Hac sezonlarında artan ticari faaliyetler, Mekke’yi sadece bir ibadet merkezi değil, aynı zamanda önemli bir ticaret merkezi haline getirmiştir. Tez, Memlükler’in ticareti destekleyen politikalarının Mekke ekonomisine olan etkisini ortaya koymayı amaçlamaktadır.This thesis examines the economic structure of Mecca during the Mamluk period, focusing particularly on trade. Mecca experienced significant commercial activity due to the pilgrimage and became a strategic hub on international trade routes. The study evaluates the Mamluks' contributions to Meccan trade, their commercial regulations, and their impact on the city's economic vitality. The increased trade activity during the pilgrimage seasons transformed Mecca into not only a center of worship but also a prominent commercial hub. The thesis aims to reveal the effects of the Mamluks' trade supporting policies on Mecca's economy
Phytochemical characterization of phenolic compounds by liquid chromatography-time of flight mass spectrometry and biological activities of peltigera neckeri, peltigera canina and peltigera ponojensis from türkiye
No full textIntroduction: Lichens are symbiotic associations that live in diverse environmental conditions. They produce metabolites such as carotenoids, lichen phenolics, and water-soluble phenolics. The study aims to determine the content and in-vitro biological activities of Peltigera lichens from Bursa province, which have not been previously investigated. Methods: Methanol and acetone extracts were analyzed. Liquid Chromatography-Time of Flight Mass Spectrometry (LC/QTOF/MS) was used for qualitative and quantitative analysis. In-vitro antioxidant and tyrosinase inhibitory activities were evaluated, along with cytotoxic activity assessments. Results: Zeaxanthin was identified in the acetone extract of P. neckeri. Vanillic acid was found to be the major component in both P. canina extracts, while neoxanthin was detected in the methanol extract. Evernic acid and usnic acid were also present in both extracts. Rosmarinic acid, rutin, and zeaxanthin were not detected in P. ponojensis extracts, whereas neoxanthin, usnic acid, and evernic acid were present. The most active extract was the methanol extract of P. ponojensis, with an IC50 value of 23.52 +/- 0.02 mu g/mL for radical scavenging. No tyrosinase inhibitory activity was observed in either extract of P. neckeri. The most active extract was methanol extract of P. ponojensis with an IC50 value of 30.588 +/- 0.02 mu g/mL. Cytotoxicity results showed no death or proliferation reduction in any tested cell lines. Conclusion: Peltigera species may serve as potential sources of antioxidants
Vocabulary of the 18th and 19th century based on Lehcetu’l Lugât and Lehce-i Osmânî
No full textBu tez çalışmasında 18. yüzyıldaki Şeyhülislam Mehmed Esad Efendi’nin Lehcetü’l Lügat ve 19. yüzyıldaki Ahmet Vefik Paşa’nın Lehce-i Osmânî adlı sözlükleri ve söz varlığı incelenmiştir. Bu çalışma giriş, sonuç ve kaynakça dışında üç bölümden oluşmaktadır. Giriş bölümünde çalışmanın amacı, önemi, problemi, yöntemi hakkında bilgi verilmiştir. Tezin birinci bölümünde genel olarak sözcük, söz varlığı, sözlükbilim, sözlük çeşitleri, sözlükçülüğün tarihçesi, Türk sözlükçülüğü tarihi ve Türkçenin sözlükleri hakkında bilgi verilmiştir. İkinci bölümde Şeyhülislam Mehmed Esad Efendi ve Ahmet Vefik Paşa’nın hayatı, edebî kişiliği ve şahsiyeti, eserleri ve teze konu olan sözlükleri hakkında açıklamalar yapılmıştır. Tezin tematik tasnif bölümünü oluşturan ve en kapsamlı içeriğe sahip olan üçüncü bölümde söz varlığı; dil bilgisi ögeleri, konulara göre adlar, konulara göre fiiller başlıkları altında incelenmiştir. Çalışmada Hatice Şirin’in “Eski Türk Yazıtları Söz Varlığı İncelemesi” adlı eserinde kullanılan tematik tasniften yararlanılmıştır. Sözcüklerin içerdiği konuya göre yeni tasnif başlıkları eklenmiştir. Sonuç bölümünde sözlüklerden hareketle elde edilen bulgular ortaya konmuş, sözlükler arasında karşılaştırmalar yapılmış, sayısal veriler sıralanmış, grafiklerle gösterilmiş ve sözlüklerin söz varlığı değerlendirilerek yorumlanmıştır. Sonuç bölümünden sonra çalışmada başvurulan kaynaklara yer verilmiştir.In this thesis, the dictionaries and vocabulary of the 18th century Şeyhülislam Mehmed Esad Efendi’s Lehcetü’l Lügat and 19th century Ahmet Vefik Pasha’s Lehce-i Osmânî were examined. This study consists of three sections, except for the introduction, conclusion and bibliography. In the introduction section, information is given about the purpose, importance, problem and method of the study. In the first section of the thesis, information is given about the word, vocabulary, lexicology, dictionary types, history of lexicography, history of Turkish lexicography and Turkish dictionaries in general. In the second section, explanations are made about the life, literary personality and character of Şeyhülislam Mehmed Esad Efendi and Ahmet Vefik Paşa, their works and the dictionaries that are the subject of the thesis. In the third section, which constitutes the thematic classification section of the thesis and has the most comprehensive content, vocabulary is examined under the titles of grammar elements, nouns according to subjects and verbs according to subjects. In the study, the thematic classification used in Hatice Şirin’s work titled “Old Turkish Inscriptions Vocabulary Analysis” was used. New classification titles were added according to the subject of the words. In the conclusion section, the findings obtained from the dictionaries were presented, comparisons were made between the dictionaries, numerical data were listed, shown with graphics and the vocabulary of the dictionaries was evaluated and interpreted. After the conclusion section, the sources used in the study were included
Immobilization and spr-based binding characterization of l-asparaginase on metal-chelated polymeric nanoparticles
No full textIn this study, poly(2-hydroxyethyl methacrylate-N-methacryloyl-(L)-histidine methyl ester-Cu2+) [PHM-Cu2+] nanoparticles were synthesized by emulsion polymerization and used as carriers for L-asparaginase (L-ASNase) immobilization. The nanoparticles were characterized using SEM-EDX, TEM, FTIR, Zeta potential analyses. The binding affinity of L-ASNase on metal-chelated polymeric nanoparticles was investigated via surface plasmon resonance (SPR) analysis. The immobilized enzyme (PHM-Cu2+-L-ASNase) achieved an immobilization yield of 86.4 %, activity yield of 73.6 %, and immobilization efficiency of 85.1 %. The optimum pH shifted from 8.5 (free) to 7.0 (immobilized), and the optimum temperature from 45 degrees C to 50 degrees C. The PHM-Cu2+-L-ASNase presented enhanced resistance to proteolysis. Kinetic studies revealed that Km and Vmax values decreased after immobilization, indicating increased substrate affinity. Immobilization also resulted in a slightly lower turnover number (kcat) compared to the free enzyme. The PHM-Cu2+-L-ASNase preserved 60 % activity after ten reuse cycles and maintained higher activity in the presence of various metal ions and organic solvents. Thermal, storage, and in vitro artificial human serum stability studies revealed that the PHM-Cu2+-L-ASNase exhibited slower inactivation and extended half-life compared to the free L-ASNase. SPR analysis demonstrated high binding affinity (KD = 0.016 IU/mL), fitting the Langmuir model. Consequently, the PHM-Cu2+ nanoparticles were effective carriers for L-ASNase enzyme, enhancing its catalytic activity, stability, and reusability for pharmaceutical and industrial use
Modular and nested structures in workplace mobbing within the construction industry: A bipartite network diagnostic approach
No full textThis study investigates workplace mobbing dynamics in the construction industry using a bipartite network approach, inspired by ecological network analysis (ENA). Mobbing, as a form of persistent psychological harassment, poses significant threats to employee well-being and organizational efficiency, particularly in construction. Traditional approaches often overlook the relational patterns between perpetrators and victims. This research introduces a network-based perspective by constructing bipartite matrices that link perpetrators, mobbing reasons, and types of harassment experienced. Metrics such as nestedness (NODF) and modularity (Leading Eigenvector method) are used to analyze behavioral structures across 180 construction professionals. The findings reveal significant modularity in certain mobbing patterns, indicating that such behaviors are concentrated within specific subgroups. Nestedness analysis uncovers hierarchical structures, where specific mobbing types emerge as subsets of broader abuse patterns, suggesting systemic organizational issues. This study offers two key methodological contributions: (1) a bipartite network framework to identify and assess mobbing clusters, enabling proactive risk identification in construction settings; and (2) the integration of ENA metrics for analyzing clustered and hierarchical harassment behaviors. These insights provide a foundation for targeted interventions, supporting workforce well-being. Furthermore, the approach is compatible with management information systems (MIS), offering construction managers a data-driven tool to mitigate mobbing, enhance employee morale, and improve overall project performance
Validation of the short form of the remote work stress scale
No full textPurposeThis study aims to develop and validate a reliable and psychometrically robust Short Form of the Remote Work Stress Scale (SRWSS), derived from the original 15-item RWSS.Design/methodology/approachFollowing the three-phase, nine-step scale development framework by Boateng et al. (2018), the study involved qualitative item generation, expert reviews, pilot study, exploratory and confirmatory factor analyses, and validation with a sample of 602 remote workers from T & uuml;rkiye. The short form was tested for reliability, validity and path analysis performed via SmartPLS with the original form and its sub-dimensions.FindingsThe SRWSS demonstrated excellent internal consistency (a = 0.88), strong construct and criterion validity, and a high correlation with the original scale (0.94). Results showed that female, highly educated and non-managerial employees reported higher levels of stress. Age was negatively correlated with stress levels.Research limitations/implicationsThe sample is confined to a specific demographic (Turkish remote workers), necessitating cross-cultural validation to ensure generalizability.Practical implicationsThe scale enables quick stress assessments to inform targeted interventions and HR strategies in remote and hybrid work settings.Social implicationsFindings highlight demographic disparities in remote work stress, informing equitable workplace policy development.Originality/valueThis study pioneers the development of a validated, unidimensional 5-item scale, offering a novel, efficient instrument for assessing remote work stress, enhancing research and practice in HRM
The science of qiraat in al-Qayrawan
No full textGünümüzde Tunus ülkesinin sınırları içerisinde bulunan Kayrevan şehri, hicretin ilk dört buçuk asrında birçok ilmî sahada öne çıkmıştır. Doğu ile Batı arasında bir geçiş güzergahında olması hasebiyle ilim yolcularının uğrak bir şehri olmuş, çeşitli sahada birçok ulemânın ömrünün tamamını ya da bir kısmını geçirdiği kritik mekân haline gelmiştir. Kıraat ilmi hususunda da seçkin bir yere sahip olan Kayrevan’da özellikle hicretin üç, dört ve beşinci asırlarında çok kıymetli kıraat ulemâsı yetişmiştir. Ayrıca bağrında yetişen bazı kıraat âlimleri, büyük ses getiren telifler kaleme almışlar ve İslâm dünyasının farklı yerlerine rihleler yaparak çok sayıda talebe yetiştirmişlerdir. Bu çalışma, Kayrevan şehrinin kıraat ilmindeki yerini ve rolünü çeşitli yönlerden ele almaktadır. Buna göre; hicrî 50 yılında tesis edilmesinden başlayarak, ilmî merkez olma vasfını yitirdiği 449 senesine kadar kıraat ilminin Kayrevan’daki tarihî serencamı detayları ile tetkik edilmiş, gelişmesini sağlayan faktörler etraflıca işlenmiştir. Ayrıca Kayrevan kıraat birikiminin kaynakları, tercih edilen kıraat ve rivayetlere de detaylarıyla değinilmiş, nihai olarak da bu coğrafyada yetişmiş kurrâ tespit edilerek kıraate yönelik telifleri ve kıraat sahasına katkıları analiz edilmeye çalışılmıştır.Located within the present-day borders of Tunisia, the city of Qayrawan distinguished itself in numerous fields of knowledge during the first four and a half centuries following the Hijra. Owing to its position as a transitional hub between the East and the West, Qayrawan became a key destination for seekers of knowledge and evolved into a critical center where many scholars spent either part or the entirety of their lives. In the field of Qur’anic recitation in particular, Qayrawan held a distinguished status, producing numerous eminent scholars especially during the third, fourth, and fifth centuries of the Hijra. Moreover, several qirāʾāt scholars who emerged from Qayrawan authored influential works and undertook journeys to various parts of the Islamic world, educating numerous students along the way. This study explores the role and significance of the city of Qayrawan in the discipline of qirāʾāt from multiple perspectives. Accordingly, it thoroughly examines the historical development of qirāʾāt in Qayrawan, beginning with its establishment as a city in 50 AH and continuing until it lost its status as a scholarly center in 449 AH. The factors that contributed to its growth in this field are also addressed in detail. Furthermore, the study delves into the sources that shaped Qayrawan's qiraat tradition, the preferred modes of recitation and their transmissions, and ultimately identifies the notable Qurʾānic reciters who emerged from this region. Their written contributions and overall impact on the science of qiraat are analyzed comprehensively
Enhancing the CAD-RADS™ 2.0 category assignment performance of ChatGPT and DeepSeek through "few-shot" prompting
No full textObjective: To assess whether few-shot prompting improves the performance of 2 popular large language models (LLMs) (ChatGPT o1 and DeepSeek-R1) in assigning Coronary Artery Disease Reporting and Data System (CAD-RADS™ 2.0) categories. Methods: A detailed few-shot prompt based on CAD-RADS™ 2.0 framework was developed using 20 reports from the MIMIC-IV database. Subsequently, 100 modified reports from the same database were categorized using zero-shot and few-shot prompts through the models' user interface. Model accuracy was evaluated by comparing assignments to a reference radiologist's classifications, including stenosis categories and modifiers. To assess reproducibility, 50 reports were reclassified using the same few-shot prompt. McNemar tests and Cohen kappa were used for statistical analysis. Results: Using zero-shot prompting, accuracy was low for both models (ChatGPT: 14%, DeepSeek: 8%), with correct assignments occurring almost exclusively in CAD-RADS 0 cases. Hallucinations occurred frequently (ChatGPT: 19%, DeepSeek: 54%). Few-shot prompting significantly improved accuracy to 98% for ChatGPT and 93% for DeepSeek (both P<0.001) and eliminated hallucinations. Kappa values for agreement between model-generated and radiologist-assigned classifications were 0.979 (0.950, 1.000) (P<0.001) for ChatGPT and 0.916 (0.859, 0.973) (P<0.001) for DeepSeek, indicating almost perfect agreement for both models without a significant difference between the models (P=0.180). Reproducibility analysis yielded kappa values of 0.957 (0.900, 1.000) (P<0.001) for ChatGPT and 0.873 [0.779, 0.967] (P<0.001) for DeepSeek, indicating almost perfect and strong agreement between repeated assignments, respectively, with no significant difference between the models (P=0.125). Conclusion: Few-shot prompting substantially enhances LLMs' accuracy in assigning CAD-RADS™ 2.0 categories, suggesting potential for clinical application and facilitating system adoption