Van Yüzüncü Yıl University Research Information System
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An Investigation into How Gifted Seventh Graders Pose Semi-StructuredProblems Involving Integer Operations
No full textAnchusa Azurea L. (Sığır Dili) Bitkisinden Elde Edilmiş Farklı Ekstrakt ve Nanopartiküllerin Antioksidan Etkilerinin İncelenmesi
No full textEffect of CeO2 and Er2O3 co-doping on the structural and radiation shielding properties of ceramics: An experimental and theoretical evaluation
No full textThis study investigates the effects of co-doping CeO2 (cerium oxide) and Er2O3 (erbium oxide) on Al2Si2O5(OH)4–KAlSi3O8–SiO2 ceramics, fabricated via conventional firing and sintering, for photon and neutron shielding applications. Experimental measurements were performed using a133Ba source for gamma-ray shielding and a241Am/Be neutron source for neutron shielding. At 81 keV gamma-ray energy, the radiation attenuation properties of C (undoped) and Ce15Er15 (co-doped, containing 15 % CeO2 and 15 % Er2O3) ceramics showed an increase in the mass attenuation coefficient from 0.186 to 1.309 cm2/g and in the linear attenuation coefficient from 0.421 to 3.667 cm1, while the mean free path (mfp) decreased from 2.280 to 0.281 cm, indicating a clear compositional dependence. Theoretical calculations were carried out using the EpiXS program. Among the produced ceramics, the Ce25Er5 sample exhibited the highest neutron absorption rate, reaching 69.39 %. This work presents an innovative approach for co-doping CeO2 and Er2O3 for radiation shielding in ceramics; compared to single oxide doping, this double doping is seen to further enhance both gamma-ray and neutron shielding properties. These results demonstrate that CeO2- and Er2O3-doped ceramics are sustainable, cost-effective, and efficient alternatives for radiation protection in nuclear facilities, medical imaging, and space technologies.</p
Decoding sheep actions: Deep learning algorithms for in-depth analysis of behavioral reactivity
No full textThe Relationship between ChatGPT Use in L2 Writing and L2 Writing Self-Efficacy, Motivation, and Enjoyment
No full textSAĞLIK ÇALIŞANLARINDA PSİKOSOSYAL RİSKLER ÜZERİNE BİR DEĞERLENDİRME
No full textSAĞLIKÇALIŞANLARINDA PSİKOSOSYAL RİSKLER ÜZERİNE BİR DEĞERLENDİRMEAtilla DURMUŞ1*, Mustafa BİLİCİ2*1Van Yüzüncü Yıl Üniversitesi, İş Sağlığı ve GüvenliğiAnabilim Dalı, VAN, TÜRKİYE2Van Yüzüncü Yıl Üniversitesi, İş Sağlığı ve GüvenliğiAnabilim Dalı, VAN, TÜRKİYE*[email protected], 0000-0002-4145-272X*[email protected], 0000-0002-8689-6463 ÖZET Amaç:Bu çalışmanın amacı, sağlık profesyonellerinin çalışmaortamlarında maruz kaldıkları çok boyutlu psikososyal risk faktörlerini, bufaktörlerin kök nedenlerini ve çalışanların iyilik hali üzerindeki etkilerinianaliz etmektir. Araştırma, nicel verilerle tam olarak tespit edilemeyen örtükstresörleri görünür kılmayı; bu risklerin çalışanların mesleki aidiyeti, işperformansı ve hasta güvenliği üzerindeki yansımalarını bütüncül birperspektifle değerlendirmeyi hedeflemektedir.Materyal-Metot:Araştırma, olguları kendi doğal bağlamında incelemeyisağlayan nitel araştırma deseninde yürütülmüştür. Belirlenen ana konubaşlıkları üzerinden farklı stresörler ele alınarak incelenmiştir. Veriler,içerik analizi yöntemiyle kodlanarak temalaştırılmıştır.Bulgular:Personel yetersizliği ve uzun nöbetlerin yarattığıkronik yorgunluğun, iş-yaşam dengesini bozduğu ve sosyal izolasyona nedenolduğu saptanmıştır. Acı ve ölüme tanıklık etme süreçlerinin, çalışanlardaduygusal tükenme ve "merhamet yorgunluğu" yarattığı; çalışanlarınprofesyonellik adına duygularını sürekli bastırmak zorunda kaldığı görülmüştür.Karar süreçlerine katılamama, liyakatsiz görevlendirmeler ve takdireksikliğinin kuruma olan güveni zedelediği belirlenmiştir. Hasta yakınlarındangelen sözel/fiziksel şiddet riskinin, çalışma ortamında sürekli bir"tetikte olma" hali ve anksiyete yarattığı tespit edilmiştir.Sonuç: Sağlık çalışanlarının deneyimlediği psikososyalrisklerin, bireysel özelliklerden ziyade sistemsel ve örgütsel sorunlardankaynaklandığı sonucuna varılmıştır. Kaliteli sağlık hizmetininsürdürülebilirliği için, sadece bireysel baş etme stratejilerinin değil, işorganizasyonunu ve örgütsel iklimi iyileştirecek makro düzeydeki önleyicipolitikaların hayata geçirilmesi elzemdir.AnahtarKelimeler: SağlıkÇalışanları, Psikososyal Riskler, Nitel AraştırmaAN EVALUATIONOF PSYCHOSOCIAL RISKS AMONG HEALTHCARE WORKERSAtilla DURMUŞ1*, Mustafa BİLİCİ2*1Van Yuzuncu Yil University, Department of OccupationalHealth and Safety, Van, Türkiye2Van Yuzuncu Yil University, Department of OccupationalHealth and Safety, Van, Türkiye*[email protected], 0000-0002-4145-272X*[email protected], 0000-0002-8689-6463 ABSTRACT Aim: The aim of this study is to analyze themultidimensional psychosocial risk factors that healthcare professionals areexposed to in their work environments, the root causes of these factors, andtheir effects on employee well-being. The research aims to elucidate implicitstressors that cannot be fully detected through quantitative data and toevaluate the repercussions of these risks on professional belonging, jobperformance, and patient safety from a holistic perspective.Material-Method: The study wasconducted using a qualitative research design, which allows for the examinationof phenomena within their natural context. Various stressors were examinedbased on determined main subject headings. The data were analyzed using thecontent analysis method, through which codes and themes were established.Results: It was determined that chronic fatigue causedby staff shortages and long shifts disrupts work-life balance and leads tosocial isolation. It was observed that the processes of witnessing suffering anddeath create emotional exhaustion and "compassion fatigue" inemployees, and that workers are compelled to constantly suppress their emotionsfor the sake of professionalism. It was identified that lack of participationin decision-making processes, unmerited assignments, and lack of recognitiondamage trust in the institution. Furthermore, it was found that the risk ofverbal/physical violence from patients' relatives creates a constant state of"alertness" and anxiety in the work environment.Conclusion: It was concluded that thepsychosocial risks experienced by healthcare workers stem from systemic andorganizational probl
Frequency of microsporidial spores in bronchial lavage samples from immunocompetent patients with pulmonary disorders using PCR
No full textBackground: Species of microsporidia can cause pulmonary microsporidiosis by colonizing the lower respiratory tract of the host.Objective: To investigate the frequency of microsporidial spores in immunocompetent patients with lung disease.Subjects and Methods: This cross-sectional study included 65 patients admitted to Dursun Odabaş Medical Center, Van Yüzünücü Yıl University, who had undergone bronchial lavage (BAL), and were confirmed HIV-negative. Patients with conditions that weaken the immune system, such as cancer, chronic obstructive pulmonary disease (COPD), or chronic kidney failure, or those who were taking immunosuppressive medications were excluded from the study. To investigate the presence of microsporidia, BAL samples obtained from patients were examined using modified trichrome staining and conventional PCR.Results: Examinations identified pulmonary microsporidiosis in three patients (4.62%) by molecular analysis, whereas only one of these cases (1.54%) was confirmed by the modified trichrome staining method.Conclusion: As a result, we believe that microsporidiosis should be considered in patients with lung disease, regardless of the immune status.</p
Arc-based formulation and GRASP-enhanced iterated greedy algorithm for identical parallel machine scheduling with a common server
No full textThe identical parallel machine scheduling problem with a single server and sequence-dependent setup times is a challenging optimization problem with important applications in manufacturing and service industries. In such environments, several machines depend on a common server to perform setup operations before production can begin, which creates strong interdependencies and demands more effective scheduling strategies. This characteristic highlights the practical relevance of the problem. The interaction between machine availability and server operations often becomes a critical bottleneck. This study introduces two complementary approaches. The first is an exact method based on a novel arc-based mixed-integer linear programming (ABF) model, which extends the modeling capability of existing formulations by capturing server-related constraints more effectively. The second is an approximation method built on an Iterated Greedy (IG) algorithm. The IG procedure is improved by two evaluation mechanisms: one model-based evaluation derived from the proposed ABF model, and another employing a greedy randomized adaptive search procedure (GRASP)-based strategy that integrates greedy selection, randomization, and reconstruction to enhance solution quality. Computational experiments are conducted on existing benchmark instances. The results show that the proposed ABF model performs well on small and medium-sized instances compared to existing exact methods, while the IG variants, particularly the proposed GRASP-based version, deliver strong performance against state-of-the-art metaheuristics developed for this problem. In addition, 21 new best-known solutions are reported, further demonstrating the effectiveness of the proposed approaches
Explicit solution to the neutral fractional and ordinary difference delayed systems with noncommutative coefficient matrices
No full textThis paper introduces novel formulations of neutral fractional and ordinary difference delayed systems involving noncommutative coefficient matrices. The corresponding determining neutral matrix equations are established, and an explicit solution is derived through the construction of a neutral discrete delayed matrix exponential based on these equations. A couple of examples with simulations are provided to verify the theoretical findings and to illustrate the efficiency and applicability of the developed results
Using Different Machine-Learning Algorithms to Predict Dissolved Oxygen Concentration in Rainbow Trout Farms
No full textDissolved oxygen (DO) is a vital parameter in intensive rainbow trout aquaculture, directly influencing fish growth, health, and survival. As such, accurate monitoring and prediction of DO levels are crucial for ensuring sustainable and efficient aquaculture practices. This study assessed and compared the predictive performance of four machine learning algorithms Multivariate Adaptive Regression Splines (MARS), Random Forest (RF), Extreme Gradient Boosting (XGBoost), and Averaged Neural Networks (avNNet) in estimating DO concentrations based on a range of water quality parameters. A total of 120 samples were collected from 12 rainbow trout farms across Türkiye. The input variables included suspended solids, electrical conductivity, turbidity, nitrate, nitrite, ammonia, ammonium, orthophosphate, pH, water temperature, and total phosphorus. DO levels ranged between 8 and 15 mg/L. Model performance was evaluated using Mean Absolute Error (MAE), Root Mean Square Error (RMSE), Mean Absolute Percent Error (MAPE), and the coefficient of determination (R²). All models demonstrated strong predictive accuracy, with XGBoost achieving the best overall performance (MAE: 0.44, RMSE: 0.58, MAPE: 0.04, R²: 0.78), followed by RF, avNNet, and MARS. These findings highlight XGBoost as a robust predictor of dissolved oxygen levels in aquaculture systems, which may contribute to improving water quality management and increasing productivity in rainbow trout aquaculture