Allegheny College DSpace Repository
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Evaluation of the concentrations of current use pesticides (CUPs) in urban air and rainfall, and their wet deposition flux in a metropolitan environment
No full textThis study assesses the wet deposition fluxes and washout ratios of current-use pesticides (CUPs) in Bursa, Turkey, to better understand their environmental impact. It investigates the temporal and spatial fluctuations of these compounds, particularly focusing on CUPs like benomyl, dichlorvos, dimethoate, imidacloprid, monochrotophos, and pymetrozine. The concentrations of CUPs in both ambient air and precipitation showed seasonal variations, with peaks in spring and summer due to increased agricultural activities. Precipitation concentrations of CUPs also varied, when the detection rates based on CUP congeners are analyzed, benomyl (70 %) and pymetrozine (66 %) are the most frequently detected congeners in the collected samples, particularly during the peak agricultural season. Wet deposition fluxes were highest in spring and summer, while dry deposition fluxes peaked in autumn and winter. Benomyl, dichlorvos, dimethoate, and imidacloprid were determined the most abundant CUP congeners in both phase (gas and particle phase). The dry deposition velocities ranged from 0.001 to 2.26 cm/s, and washout ratios varied between 1.35 × 10−4 and 1.18 × 10−6, depending on the CUP congeners. These findings underscore the need for ongoing monitoring, enhanced measurement techniques, and interdisciplinary collaboration to better understand CUP distribution and its environmental and health impacts, while developing effective management strategies
Aerodynamic and structural analysis of a solar panel
No full textIn this study, wind loads on a ground-mounted solar panel was investigated numerically at different ground clearances and azimuth angles, and the results were compared with the experimental data. A 1:20 scaled solar panel model with 35 degrees panel inclinations was designed for a chord Reynolds number of 6.4 x 104. The studies were performed for the azimuth angles between 0 degrees-180 degrees in 30 degrees increments and ground clearances of 0 to 0.06 m. In the numerical analyses, Computational Fluid Dynamics was calculated with 3 different turbulence models. The results showed that higher ground clearances caused stronger vortex shedding fluctuations, higher velocity zones, and shedding frequencies, and shorter vortex scales behind the panel. The critical wind directions were determined as 30 degrees and 150 degrees in terms of overturning moments, while the maximum value of both the lift and drag coefficient were obtained at 180 degrees azimuth angle. In addition, a hurricane scenario with a wind velocity of 33 m/s was created on a 1:1 scaled model and fluid-structure interaction simulation was performed. The numerical results of the aerodynamic loads were in a good agreement with the experimental results
Augmented reality in engineering education: An application for electronic circuits laboratory
No full textEngineering education faces challenges in effectively conveying complex theoretical knowledge and practical skills. Traditional teaching tools like smart boards, education kits, web pages, and computer-based simulators often fall short in bridging the gap between theory and hands-on application. Augmented reality (AR) has emerged as a promising solution to fill this educational gap by providing immersive and interactive learning experiences. In this study, an AR-based application has been developed for operational amplifiers. Agile methodology and the ADDIE learning development model were used in the system development and instructional design of this application. This application, which requires only a smartphone and a breadboard, detects the circuit marker when users point their smartphone camera at it. After detection, the user can interact with the interface to choose whether the system shows input–output signals for different component values, the output voltage formula, a 3D model, or a brief lecture about the used amplifier. These virtual elements are overlaid onto the real-world breadboard based on the user's selection. This integration of AR technology provides an immersive, interactive learning experience, allowing students to visualize and interact with circuit elements in real time
Has open access in neurosurgery made access easier but sharing harder? A national survey from an lmic (Turkey)
No full textOpen access (OA) publishing facilitates free access to knowledge. However, OA journals often demand high article processing charges (APCs), which pose significant challenges for authors from low- and middle-income countries (LMICs). This study aimed to investigate the perspectives of Turkish neurosurgeons on OA publishing, and to identify the challenges they face during the publication process. A national online survey was conducted in April-May 2025 and was completed by 210 neurosurgeons. The survey collected data on demographics, academic productivity, funding access, and opinions on OA versus hybrid publishing models. The highest participation rate was among specialists (n = 86), followed by residents (30.5%), associate professors (12.9%), professors (10.5%), and assistant professors (5.2%). In total, 43.3% reported authorship of at least one SCI-E publication in the past year. Of the 70 participants who had paid APCs, 23 obtained support for at least one manuscript, 49 fully self-funded at least one, and 15 reported adding non-contributing co-authors to reduce costs. Among those who paid alone, 28/49 stated they would not have done so if they had already achieved their target academic title. Additionally, 49.5% believed that selecting the OA option increases the likelihood of acceptance, while 30.5% anticipated a long-term decline in the quality of fully OA journals compared to hybrid ones. While OA publishing improves access to academic content, the lack of adequate funding mechanisms in LMICs hinders the ability of researchers to disseminate their findings. This imbalance may risk driving authors toward predatory journals and compromise academic integrity
Retrospective evaluation of the effects of antiviral treatment regimens on Hepatitis B reactivation and renal function tests in kidney transplant recipients with Hepatitis B
No full textGiriş ve Amaç: Böbrek nakli yapılan ve kronik hepatit B nedeniyle antiviral tedavi alan hastalarda, farklı tedavi rejimlerinin hepatit B reaktivasyonu ve böbrek fonksiyonlarına etkisi belirsizdir. Bu çalışmada, farklı antiviral ilaçların HBV reaktivasyonu ve böbrek fonksiyon testleri üzerindeki etkileri retrospektif olarak değerlendirildi. Yöntem: Bursa Uludağ Üniversitesi Tıp Fakültesi Hastanesi’nde 2015-2025 yılları arasında böbrek nakli sonrası antiviral tedavi alan 38 hasta çalışmaya dahil edildi. Hastalar kullanılan antiviral ilaca göre gruplara ayrılarak HBV DNA, HBsAg, ALT, AST, kreatinin, GFH, fosfor seviyeleri değerlendirildi. Bulgular: Lamivudin tedavisi alan hastalarda HBV reaktivasyonu oranı %66,7 olup, TAF (%0, p<0,01) ve Entekavir (%7,7, p<0,05) kullanan hastalara kıyasla anlamlı olarak daha yüksekti. TAF kullanan hastaların tamamında (n:26) HBV DNA negatifleşirken, Lamivudin grubunda bu oran yalnızca %33,3 olarak bulundu (p<0,01). Böbrek fonksiyonları açısından incelendiğinde, TAF kullanan hastalarda kreatinin değişimi (-%3, p=0,45) ve GFH değişimi (-%1,6, p=0,96) istatistiksel olarak anlamlı farklılık göstermedi. Fosfor seviyelerinde ise TAF grubunda belirgin bir azalma (p=0,007) gözlendi. Siklosporin kullanımının HBV reaktivasyonu ile ilişkili olduğu saptandı (p<0,01) buna karşılık diğer immünsüpresif tedavilerle HBV reaktivasyonu arasında ilişki saptanmadı. Sonuç: Böbrek nakli sonrası KHB nedeniyle antiviral tedavi alan hastalarda, TAF ve Entekavir kullanımı HBV reaktivasyonunu önlemede daha etkili bulundu, Lamivudin kullanımının ise yüksek reaktivasyon oranları ile ilişkili olduğu görüldü (p<0,05). Böbrek fonksiyonları açısından TAF, güvenli bir seçenek olarak değerlendirilmektedir.Introduction and Objective: The effects of different antiviral treatment regimens on hepatitis B reactivation and renal function in kidney transplant recipients with chronic hepatitis B (CHB) remain unclear. This study retrospectively evaluated the impact of various antiviral drugs on HBV reactivation and renal function tests. Methods: A total of 38 kidney transplant recipients who received antiviral treatment at Bursa Uludağ University Faculty of Medicine Hospital between 2015 and 2025 were included in the study. Patients were categorized based on the antiviral drugs used, and HBV DNA, HBsAg, ALT, AST, creatinine, GFH, and phosphorus levels were analyzed. Results: The HBV reactivation rate was significantly higher in patients receiving lamivudine (66.7%) compared to those receiving tenofovir alafenamide (TAF) (0%, p<0.01) and entecavir (7.7%, p<0.05). HBV DNA became undetectable in all patients treated with TAF (n:26), whereas this rate was only 33.3% in the lamivudine group (p<0.01). Regarding renal function, changes in creatinine levels (-3%, p=0.45) and GFH (-1.6%, p=0.96) in TAF users were not statistically significant. However, phosphorus levels showed a significant decrease in the TAF group (p=0.007). Cyclosporine use was found to be associated with HBV reactivation (p<0.01), whereas no significant relationship was observed between other immunosuppressive treatments and HBV reactivation
ASO visual abstract: Breast cancer recurrence in ınitially clinically node-positive patients undergoing sentinel lymph node biopsy after neoadjuvant chemotherapy in the NEOSENTITURK-trials MF18-02/18-03
No full textPlasma levels of nesfatin-1, parathyroid hormone and calcitonin in a rat model of cecal ligation and incision-induced septic shock
No full textConsidering the anti-inflammatory and shock-reversing effects of nesfatin-1 (NESF-1), the current study aimed to investigate the changes in plasma NESF-1 levels in septic shock conditions that produce both hypotensive and inflammatory effects. The changes in parathyroid hormone (PTH) and calcitonin (CT) plasma levels, which have anti-inflammatory activity and play a role in regulating Ca metabolism, such as plasma NESF-1, in septic shock conditions, were also investigated in the study. In the current study, adult male Wistar albino rats were used. Under sevoflurane anesthesia, the animals were catheterized in the femoral arteries to provide monitoring of mean arterial pressure (MAP) and heart rate (HR), as well as for blood sampling. Then, the cecal ligation and incision (CLI) method was applied to rats to induce experimental septic shock. For control, sham-operated animals were used. The cardiovascular parameters of all animals were monitored for 3 hours starting from hour 0. In addition, 0.5 ml of blood samples in the tubes containing EDTA were collected from the animals through the arterial catheter at 0, 1, and 3 hours. NESF-1, PTH, and CT levels from plasma extracted from collected blood samples were measured using the ELISA method. Data obtained from two groups, septic shock and control, were compared statistically using the Benferoni test after repeated-measures ANOVA. Septic shock gradually caused a decrease in the MAP and an increase in the HR of the rats. Remarkably, animals in the septic shock group exhibited a statistically significant time-dependent increase in plasma NESF-1, PTH, and CT levels compared to the control group. These findings indicate elevated plasma levels of NESF-1, PTH, and CT in correlation with the severity of septic shock, suggesting a potential protective role for endogenous NESF-1, PTH, and CT in the pathophysiology of the condition. Additionally, these increases may be a prognostic biological indicator related to the severity of septic shoc
Investigation of circular RNAs (circRNAs) as potential biomarkers in bladder pain syndrome / interstitial cystitis (BPS/IC) disease
No full textMesane Ağrı Sendromu/İnterstisyel Sistit (MAS/İS), hastaların yaşam kalitesini önemli ölçüde etkileyen, bakteriyel enfeksiyon veya tanımlanabilir bir patolojik neden olmaksızın idrar sıklığı, aciliyet, noktüri ve pelvik ağrı ile karakterize kronik bir hastalıktır. MAS/İS’ın patogenezi ve patofizyolojisi tam olarak anlaşılamamakla birlikte ürotelyum yüzeyini kaplayan glikozaminoglikanların eksikliği, immünolojik etiyoloji, aktif mast hücreleri, nöral değişiklikler ve enflamasyonu içeren çeşitli teoriler öne sürülmektedir. Hastalığın tanısında altın standartlar yoktur ve klinisyenler tedaviye başlamak için eşlik eden hastalıklardan ortak olan birkaç semptomu ekarte etmek durumundadır. Erken tanıdaki komplikasyonlar tedaviyi zorlaştırmakta ve hastaların yaşam kalitesini düşürmektedir. Dolayısıyla hastalığın altında yatan mekanizmaların aydınlatılması ve etkili tedavi stratejilerinin belirlenebilmesi için tanısal belirteçlere ihtiyaç duyulmaktadır. Vücut sıvılarında stabilite, korunma ve yüksek bolluk gibi özellikleri ile dairesel RNA’lar (circRNA’lar), çeşitli hastalıkların teşhisi, izlenmesi ve prognozu için biyobelirteçler olarak büyük potansiyel sunmaktadır. Mevcut tez çalışmasında, potansiyel bir biyobelirteç olan circRNA’ların, MAS/İS’in tanısı ve patogenezi üzerindeki rolü araştırıldı. Bu amaç kapsamında, sağlıklı ve hasta bireylerden elde edilen kan/doku örneklerinden circRNA, miRNA ve mRNA izolasyonunu takiben cDNA sentezi yapıldı. Ardından literatür taraması ve biyoinformatik analizler sonucu belirlenen 11 aday circRNA’nın ifadesi kantitatif gerçek zamanlı polimeraz zincir reaksiyonu ile belirlenerek sağlıklı ve hasta bireyler arasındaki ifade farklılıkları kıyaslandı. Elde edilen sonuçlar, circPTPN22 ve circMYBL2’nin hastalığın patogenezinin aydınlatılmasında potansiyel biyobelirteçler olarak kullanılabileceğini göstermektedir.Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS) is a chronic disease characterized by urinary frequency, urgency, nocturia, and pelvic pain in the absence of bacterial infection or an identifiable pathological cause, significantly impacting patients' quality of life. The pathogenesis and pathophysiology of IC/BPS remain incompletely understood, with various hypotheses proposed, including a deficiency in glycosaminoglycans covering the urothelial surface, immunological etiology, activated mast cells, neural alterations, and inflammation. Currently, there are no established gold standards for diagnosing the disease, and clinicians must exclude several comorbid conditions with overlapping symptoms before initiating treatment. Challenges in early diagnosis complicate therapeutic interventions and further reduce patients’ quality of life. Therefore, diagnostic biomarkers are essential for elucidating the underlying mechanisms of the disease and developing effective therapeutic strategies. Due to their stability, protection, and high abundance in bodily fluids, circular RNAs (circRNAs) offer great potential as biomarkers for the diagnosis, monitoring, and prognosis of various diseases. The present dissertation investigates the role of circRNAs as potential biomarkers in the diagnosis and pathogenesis of IC/BPS. In this context, circRNA, miRNA, and mRNA were isolated from blood/tissue samples obtained from healthy and diseased individuals, followed by cDNA synthesis. Subsequently, the expression levels of 11 candidate circRNAs, identified through literature review and bioinformatics analyses, were determined using quantitative real-time polymerase chain reaction (qRT-PCR) and compared between healthy and diseased individuals. The findings indicate that circPTPN22 and circMYBL2 may serve as potential biomarkers for elucidating the pathogenesis of IC/BPS
Analysis of Surah al-Fatiha in the context of spiritual counseling and guidance
No full textBu çalışmada, Kur’ân-ı Kerîm’in özeti olarak kabul edilen Fâtiha Sûresi’nin, manevi danışmanlık ve rehberlik bağlamında ele alarak, merhum Elmalılı’nın Hak Dini Kur’ân Dili eseri üzerinden âyet âyet incelenmiştir. Araştırmanın temel amacı, sûrenin her bir âyetinin bireyin içsel gelişimi, yön arayışı ve Allah ile kurduğu bağ açısından nasıl bir rehberlik sunduğunu anlamaya çalışmaktır. Bu bağlamda Fâtiha, insanın varoluşsal bütünlüğünü yeniden inşa eden, dua formu içinde şekillenmiş kılavuz bir metin olarak ele alınmıştır. Çalışmanın temel varsayımı, Fâtiha Sûresi’nin bireyin yaşamsal yolculuğunda karşılaştığı çatışmalar, arayışlar, hatalar, yönelişler ve umutlar için iletişimsel ve yaşamsal bir yol haritası sunduğudur. Sonuç olarak bu tez, Fâtiha Sûresi’nin sadece bir dua değil; aynı zamanda manevi danışmanlık ve rehberlik üzerinden analiz ederek kişinin içsel dengesini kurabileceği, varoluşsal farkındalık geliştirebileceği, geçmişiyle barışıp geleceğini daha bilinçli inşa edebileceği kılavuz bir metin olduğunu ortaya koymayı amaçlamıştır.In this study, the Sūrah al-Fātiḥah -regarded as the summary of the Qur’ān- has been examined verse by verse within the context of spiritual counseling and guidance, based on the late Elmalılı Hamdi Yazır’s monumental exegesis Hak Dîni Kur’ân Dili. The primary aim of the research is to explore how each verse of the Fātiḥah provides guidance for an individual’s inner development, search for direction, and connection with God. In this regard, the Fātiḥah is approached as a guiding text shaped in the form of a prayer that reconstructs the existential integrity of the human being. The main assumption of this study is that the Fātiḥah offers a communicative and existential roadmap for the conflicts, quests, errors, orientations, and hopes encountered throughout an individual’s spiritual journey. It is not merely a supplication but also a profound framework through which one can establish inner balance, develop existential awareness, reconcile with the past, and consciously construct the future. Consequently, this thesis aims to reveal that Sūrah al-Fātiḥah, when analyzed through the lens of spiritual counseling and guidance, functions as a holistic guide that integrates the psychological and spiritual dimensions of human existence, offering direction and meaning to the believer’s life journey
