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Assesment of the clinical usability of magnetic resonance imaging with gadoxetic acid in the diagnosis of alkaline reflux gastritis
Get PDFAlkalen reflü gastrit duodenumdaki safra ve pankreatik salgıların mideye reflüsü sonucu mide mukozasının hasarlanmasıdır. Klinik olarak spesifik semptomlarının olmaması nedeniyle zor tanı almaktadır. Kesin tanı için endoskopik olarak midede mukozal eritem, safra ile safra tuzlarının görülmesi ve histopatolojik değerlendirme gerekmektedir. Tedavi seçenekleri; yaşam tarzı değişiklikleri ve ilaç tedavilerinden, cerrahi müdahalelere kadar uzanmaktadır. Gadoksetik asit (gadolyum etoksibenzil dietilentriaminpentasetik asit) karaciğere özgü bir manyetik rezonans görüntüleme(MRG) kontrast ajanıdır. Uygulanan dozun %50'sine kadar fonksiyonel hepatositler tarafından alınır ve ardından safra kanalına atılır. Klinik uygulamada, gadoksetik asit ile yapılan MR kolanjiografi'de (G-MRK) safra kanalından atılan kontrast maddenin mide lümeninde sıkça görüldüğü gözlemlenmektedir. Bunun duodenogastrik safra reflüsünü temsil edebileceğini ve alkalen reflü gastritin, MRK'nin geç fazında midede kontrast maddenin varlığı ile yakından ilişkili olabileceğini varsaydık. Düzce Üniversitesi Tıp Fakültesi Genel Cerrahi kliniğindeki hastalar retrospektif olarak tarandı. Kriterleri karşılayan endoskopik olarak tanı almış 103 alkalen reflü gastrit hastası ve endoskopisinde alkalen reflü gastrit görülmeyen 103 kontrol hastası çalışmaya dahil edildi. Çalışmamızda, G-MRK yönteminin alkalen reflü gastrit tanısındaki etkinliği değerlendirildi; %82,52 duyarlılık ve %74,76 özgüllük ile istatistiksel açısından anlamlı, literatür ile uyumlu sonuçlar elde edildi. Sonuç olarak; MRG'nin ARG tanısında non-invaziv, radyasyon yaymayan, yüksek çözünürlüklü, geniş bir görüş alanı ve süresi sunan mevcut tanı yöntemlerine iyi bir alternatif olabileceğini düşünmekteyiz.Alkaline reflux gastritis is the damage to the gastric mucosa as a result of the reflux of bile and pancreatic secretions from the duodenum into the stomach. Clinically, it is difficult to diagnose due to the absence of specific symptoms. For a definitive diagnosis, endoscopic findings of mucosal erythema, the presence of bile and bile salts in the stomach, and histopathological evaluation are necessary. Treatment options range from lifestyle modifications and medication to surgical interventions. Gadoxetic acid (gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid) is a liver-specific magnetic resonance (MR) contrast agent. Up to 50% of the administered dose is taken up by functional hepatocytes and subsequently excreted into the bile ducts. In clinical practice, it has been observed that contrast material excreted from the bile ducts is often seen in the gastric lumen during MR cholangiography (G-MRC) enhanced with gadoxetic acid. We hypothesized that this could represent duodenogastric bile reflux and that the presence of contrast material in the stomach during the late phase of MRC could be closely related to alkaline reflux gastritis. Patients from the General Surgery Department at Düzce University Faculty of Medicine were retrospectively analyzed. The study included 103 patients diagnosed with alkaline reflux gastritis through endoscopy and 103 control patients without alkaline reflux gastritis findings on endoscopy. In our study, the effectiveness of the G-MRC method in diagnosing alkaline reflux gastritis was evaluated, yielding statistically significant results with a sensitivity of 82.52% and a specificity of 74.76%, consistent with the literature. In conclusion, we believe that MRI can serve as a good alternative to current diagnostic methods for alkaline reflux gastritis, offering a non-invasive, radiation-free, high-resolution imaging modality with a wide field of view and extended duration
INVESTIGATION OF SUB-SYNCHRONOUS RESONANCE PHENOMENA IN DFIG BASED WIND FARM WITH TCSC IN DIFFERENT APPROACHES
Get PDFÇift Beslemeli Asenkron Generatör (ÇBAG) tabanlı rüzgar türbinlerinin şebekeye bağlantısında hattaki seri kompanzasyon oranlarının en uygun şekilde belirlenmesi ile sistemin kararlılığın sağlanması önemli bir konudur. Bu oranlar iyi belirlenmez ise Alt Senkron Rezonans (SSR) isimli elektromekanik salınımların artması durumları meydana gelebilmektedir. Bu gibi problemleri ortadan kaldırmak için bu çalışmada ÇBAG tabanlı rüzgar türbinlerinde Tristör Kontrollü Seri Kompanzatör (TCSC) kullanılarak farklı rüzgar hızları yaklaşımı ile iletim hattındaki farklı seri kompanzasyon oranlarındaki değişimler detaylı olarak incelenmiştir. Bu analizlerde ÇBAG’da farklı rüzgar hızları olarak 9 m/s, 12 m/s ve 15 m/s olarak seçilirken, iletim hattındaki seri kompanzasyon oranları olarak %60, %70 ve % 80 değerleri ele alınmıştır. MATLAB/SIMULINK ortamında gerçekleştirilen bu analizlerde ÇBAG aktif güç, reaktif güç, DC bara gerilimi ve açısal hız değerleri detaylı bir şekilde incelenmiştir. Elde edilen sonuçlar neticesinde ÇBAG’da rüzgar hızının 12m/s rüzgar hızında olduğu durumda ve sistemdeki seri kompanzasyon oranın %60 olduğu durumda sistem kararlılığının sağlandığı ve oluşan salınımların hızlıca sönümlendiği görülmüştür.In the connection of Doubly Fed Induction Generator (DFIG) based wind farms to the grid, it is important to ensure the stability of the system by determining the series compensation ratios in the line in the most appropriate way. If these ratios are not determined well, an increase in electromechanical oscillations called Sub-Synchronous Resonance (SSR) may occur. In order to eliminate such problems, in this study, the changes in different series compensation ratios in the transmission line were examined in detail with the approach of different wind speeds using Thyristor Controlled Series Compensator (TCSC) in DFIG based wind farms. In these analyses, while different wind speeds in DFIG were selected as 9 m/s, 12 m/s and 15 m/s, the series compensation ratios in the transmission line were considered as 60%, 70% and 80%. In these analyses performed in MATLAB/SIMULINK environment, DFIG active power, reactive power, DC bus voltage and angular speed values were examined in detail. As a result of the obtained results, it was observed that when the wind speed in DFIG is 12m/s and the series compensation ratio in the system is 60%, system stability is ensured and the oscillations that occur are quickly damped
Green Chemistry and Microbial Defense: Evaluating Glycyrrhiza glabra Leaf Extracts, SEM Catalysts, and Antibacterial Agents
Get PDFThe green catalytic synthesis of metallic nanoparticles from medicinal plants offers a sustainable and eco-friendly approach toward nanoparticle production. This study also explored the antimicrobial potential of nanoparticles, representing promising implications for their application in combating microbial pathogens. We describe the eco-friendly synthesis of silver nanoparticles (Ag NPs) utilizing leaf extract from Glycyrrhiza glabra. The green chemically synthesized Ag NPs are thoroughly characterized using UV-visible spectroscopy, FT-IR, XRD, SEM, and EDXA nano techniques. The peak absorbance of XRD represent maximum lambda = 517 nm, demonstrate the presence of agglomerated particles in the Ag NPs attributed to surface plasmon resonance. The XRD pattern of Ag NPs revealed distinct peaks at specific angles, indicating the lattice spacing within the crystalline structure. FTIR spectra corroborated the existence of phenols, amines, alcohols, and flavonoids within the leaf extract of Glycyrrhiza glabra. SEM analysis depicted spherical Ag NPs with sizes ranging from 30 to 41 nm, and moderate particle agglomeration was observed. The EDAX spectra of the synthesized green Ag NPs reveal prominent peaks aligning with Ag at 3.0 eV. The antibacterial activity performed on E. coli, S. aureus, P. aeruginosa, and B. subtilis demonstrated significant zones of inhibition (ZOI) measuring 13.3, 15.8, 11.5, and 12.2 mm, respectively. The findings reflect potential of Ag NPs as a viable treatment option for infectious diseases caused by the tested pathogens. Thus, the utilization of G. glabra for the synthesis of Ag NPs presents a novel avenue in antimicrobial therapy. This approach holds significant to address the microbial infections and signify the potential of natural resources in combating healthcare challenges.King Saud University, Riyadh, Saudi Arabia [ORF-2025-100]This work was supported by Ongoing Research Funding Program, (ORF-2025-100), King Saud University, Riyadh, Saudi Arabia
Measurement and Optimization of Wood Dust and Noise Levels in Table Saw Operations Using Response Surface Methodology
Get PDFExposure to airborne dust and noise during woodworking operations pose serious occupational health risks. This study investigated the influence of key cutting parameters -rotational speed, feed rate, tooth count, and dust collection system status -on PMio concentration and noise levels during circular sawing. Experimental measurements were conducted on six materials, including solid wood species (Scots pine, Oriental beech) and engineered wood products (plywood, medium-density fiberboard, oriented strand board, and particleboard). The collected data were analyzed using response surface methodology (RSM) to optimize cutting conditions, aiming to minimize emissions while maintaining operational efficiency. The results indicated that both material type and processing parameters notably affected dust and noise levels. Optimized cutting settings led to a measurable reduction in exposure, offering practical guidelines for improving workplace safety in the woodworking and furniture industries. This study contributes to the development of safer and more sustainable machining practices by addressing the hidden risks associated with dust and noise pollution
Synthesis of magnesium monoperoxyphthalate (MMPP) used as bleach for denim industry, denim fabric applications and some analysis for human health impacts
Get PDFThis study aimed to synthesize the eco-friendly organic bleach magnesium bis(monoperoxyphthalate) hexahydrate (MMPP) using a modified method and to develop various chelating agents to enhance its effectiveness. Additionally, the study sought to determine the antimicrobial and cytotoxic properties of MMPP and to compare it with KMnO4, which is actively used in the denim industry. As a result of the studies, a highly efficient molecule that can be used in denim bleaching was synthesized with a new modified method specific to this study. Furthermore, maximum efficiency in bleaching applications was achieved by using C6H6MgO7 (5%) and HEDP (5%) as chelating agents. Furthermore, it was determined that MMPP has high inhibitory activity against pathogenic microorganisms at low doses (MIC values; 312.5-625.0 mu g/mL for bacteria and 4-8 mg/mL for yeast). It was determined that antibacterial dosages were not cytotoxic. MMPP did not show any toxic effect against eukaryotic cells in the range of 1 mu g/mL - 1 mg/mL. These studies were compared with KMnO4, which is used all over the world in bleaching technology and is in the class of very dangerous chemicals. It was determined that MMPP and KMnO4 have similar bleaching effects in fabric applications. KMnO4 does not have antimicrobial activity and its cytotoxic activity results are like MMPP. It can be said that MMPP has a superior feature compared to KMnO4, thanks to its antimicrobial properties. Finally, MMPP differs from existing bleach chemicals in that it has high antimicrobial activity and does not have cytotoxic activity and can be said to be a strong alternative to dangerous bleaches as KMnO4. Compared to other bleaching agents, the most significant advantage of the MMPP molecule is that it does not generate harmful by-products and poses no threat to human health or the environment
İşletmelerin Dijital Dönüşüm Olgunluğunun Sürdürülebilir Performanslarına Etkisi
Get PDFBu araştırmanın amacı dijital dönüşüm olgunluğu (DDO) ile sürdürülebilir performans (SP) arasındaki ilişkiyi incelemektir. Araştırmada nicel araştırma yöntemlerinden ilişkisel tarama modeli kullanılmış, veri toplama aracı olarak anket tekniği tercih edilmiştir. Araştırma örneklemi, çeşitli sektörlerde ve işletmelerin üretim, pazarlama, ar&ge, muhasebe ve bilgi teknolojileri birimlerinde görev yapan ve çalışmalarında teknoloji yoğun faaliyet gösteren kişilerden (328 kişi) oluşmaktadır. Veriler analizinde SPSS kullanılmıştır. Dijital dönüşüm olgunluğu; stratejik yönelim&kültürel uyum, teknolojik yeterlilik ve yönetişim olmak üzere üç boyutta, sürdürülebilir performans ise süreç performansı ve sonuç performansı olmak üzere iki boyutta incelenmiştir. Araştırma sonuçlarına göre araştırma sorunsalını oluşturan her iki hipotezde kabul edilmiştir. Genel anlamda bir değerlendirme yapıldığında işletmelerin sürdürülebilir performansı yakalamasının ve artırmasının önemli koşullarından birisinin, dijital dönüşüm olgunluk düzeylerini artırmaları olduğunu söylemek mümkündür. Spesifik bir değerlendirme yapılacak olursa elde edilen bulgulara göre dijital olgunluğun stratejik yönelim&kültürel uyum boyutu her iki performans türü (süreç-sonuç) içinde kritik bir unsur iken sonuç performansı için teknolojik yeterlilik boyutu daha önemli süreç performansı içinse yönetişim boyutu daha önemlidir
Is Lactate Clearance Useful in Predicting Cardiopulmonary Resuscitation Outcome and 48-Hour Mortality?
Get PDFObjective: To investigate the predictive value of lactate clearance (AL) in witnessed cardiac arrest patients in the emergency department (ED) at two time points: Cardiopulmonary resuscitation (CPR) outcome and 48-hour mortality. Study Design: Observational study. Place and Duration of the Study: Department of Emergency Medicine, Duzce University, Duzce, Turkiye, from July 1 to December 31, 2023. Methodology: Patients aged 18 years and older presenting with cardiac arrest in the ED, whose relatives signed the informed consent form, were included. Out-of-hospital cardiac arrest, trauma-related cardiac arrest, major bleeding, and known malignancy were excluded from the study. All patients who met the criteria were included. All data were recorded prospectively. Receiver operating characteristic (ROC) analysis and risk analysis were performed for lactate clearance (AL) and 20-minut Results: The predictive power of AL at 10 minutes (AL0-10), 20 minutes (AL0-20), and between 10 and 20 minutes (AL10-20) was found to be significantly high for both the likelihood of no-ROSC (return of spontaneous circulation) and 48-hour mortality across all patients. The AUC values for AL at first 10 minutes, 20 minutes, and within 10-20 minutes were 0.991, 0.997, and 0.944, respectively for the no-ROSC group, and 0.942, 0.947, and 0.882, respectively for 48-hour mortality in the ROSC group. ROSC was not achieved in any patient with AL0-20 value of <=-0.15. AL below the calculated thresholds increased the risk of not achieving ROSC and 48-hour mortality by tenfold. Conclusion: AL during CPR is a useful tool to predict the outcome of CPR and 48-hour mortality. The AL0-20 value was evaluated as a valuable parameter that can be used after the 20th minute of CPR when deciding whether to continue or terminate CPR
The relationship between teachers' personality traits and self-efficacy perceptions and their emotional labor behaviors
Get PDFBu araştırmada, öğretmenlerin Beş Faktörlü Kişilik Özellikleri ile öz yeterlik algılarının duygusal emek davranışları üzerindeki ilişkileri incelenmiştir. 2024–2025 eğitim-öğretim yılında Tekirdağ ili Kapaklı ilçesindeki devlet ortaokullarında görev yapan 215 öğretmen üzerinde gerçekleştirilen araştırmada ilişkisel tarama modeli kullanılmış; veriler Beş Faktörlü Kişilik Ölçeği, Öğretmen Öz Yeterlik Algısı Ölçeği ve Duygusal Emek Ölçeği aracılığıyla toplanarak SPSS 27 programında analiz edilmiştir. Bulgulara göre öğretmenlerin uyumluluk, sorumluluk ve açıklık kişilik özellikleri bakımından katılıyorum düzeyinde görüş belirttikleri, yani bu özelliklerin güçlü şekilde hissedildiği; öz yeterlik algılarının ise yüksek düzeyde olduğu görülmüştür. Duygusal emek davranışları açısından öğretmenlerin samimi davranışlarının çoğu zaman, derinden rol yapma davranışı bazen, yüzeysel rol yapma davranışı ise çok nadir düzeyinde gerçekleştiği belirlenmiştir. Cinsiyete göre yalnızca nevrotiklik kişilik özelliği ve sınıf yönetimi öz yeterliği alt boyutlarında anlamlı farklılıklar ortaya çıkarken, görev yaptıkları okulda geçen süreye bağlı olarak uyumluluk kişilik özelliği ve derinden rol yapma davranışı alt boyutlarında; meslekteki hizmet süresine göre ise sadece sınıf yönetimi öz yeterliği alt boyutunda anlamlı fark olduğu tespit edilmiştir. Korelasyon analizleri, uyumluluk, sorumluluk ve açıklık kişilik özelliklerinin, derinden rol yapma ve samimi davranış alt boyutları ile olumlu; nevrotiklik kişilik özelliğinin ise olumsuz yönde ilişkili olduğunu göstermiştir. Regresyon analizleri sonucunda yüzeysel rol yapma davranışını en güçlü biçimde uyumluluk ve sorumluluk kişilik özelliklerinin yordadığı; samimi davranış alt boyutunda uyumluluk ve dışadönüklük kişilik özelliğinin olumlu yordayıcı olduğu; derinden rol yapma alt boyutunda ise uyumluluk ve nevrotiklik kişilik özelliğinin anlamlı etkili olduğu bulunmuştur. Bu sonuçlar, öğretmenlerin kişilik özellikleri ve mesleki öz yeterlik algı düzeylerinin sınıf ortamındaki duygusal emek davranışlarını şekillendirmede önemli rol oynadığını ve eğitim süreçlerinde bireysel farklılıkların anlaşılmasına katkı sunduğunu göstermektedir. Anahtar Sözcükler: Duygusal emek, öğretmen öz yeterlik algısı, beş faktör kişilik özellikleriThis study investigates the relationships between teachers' Big Five Personality Traits and their self-efficacy perceptions on emotional labor behaviors. The research was conducted with 215 teachers working in public middle schools in the Kapaklı district of Tekirdağ province during the 2024–2025 academic year, employing a relational survey model. Data were collected through the Big Five Personality Inventory, the Teacher Self-Efficacy Perception Scale, and the Emotional Labor Scale, and analyzed using SPSS 27. According to the findings, teachers expressed agreement at a high level concerning the personality traits of agreeableness, conscientiousness, and openness, indicating these traits were strongly felt. Their self-efficacy perceptions were also found to be high. In terms of emotional labor behaviors, teachers reported frequently engaging in genuine emotional expression, sometimes engaging in deep acting, and rarely engaging in surface acting. Significant differences were identified only in the neuroticism personality trait and classroom management self-efficacy subdimensions according to gender; in the agreeableness trait and deep acting subdimension according to years of experience in their current school; and solely in the classroom management self-efficacy subdimension according to overall professional experience. Correlation analyses showed that agreeableness, conscientiousness, and openness were positively associated with the subdimensions of deep acting and genuine emotional expression, while neuroticism was negatively associated. Regression analyses revealed that surface acting was most strongly predicted by agreeableness and conscientiousness; that agreeableness and extraversion positively predicted genuine emotional expression; and that agreeableness and neuroticism significantly influenced deep acting. These results demonstrate that teachers' personality traits and their level of professional self-efficacy perceptions play an important role in shaping their emotional labor behaviors in classroom settings, contributing to the understanding of individual differences within educational processes
A model proposal for disaster resilient neighborhoods: Düzce City case
Get PDFThis study explored methodologies for measuring resilience, with the Baseline Resilience Indicators for Communities (BRIC) model selected as the measurement and evaluation method owing to its local applicability. Düzce City (Türkiye), which is frequently subjected to floods and earthquakes, particularly after two consecutive earthquakes in 1999, was chosen as the study site. In this area, the resilience of neighborhoods before and after the 1999 earthquake was investigated. Based on the dimensions and indicators of the BRIC model, four dimensions (ecological, social, economic, and spatial infrastructure) and 16 indicators were selected. The dimensions and indicators were weighted using expert surveys, the Analytical Hierarchy Process (AHP), and Geographic Information Systems. As a result, neighborhoods before the 1999 earthquake were determined to be less resilient than those after the earthquake. © 2025 Elsevier B.V., All rights reserved
The Genoprotective Role of Laurocerasus officinalis: Study on Genotoxic/Antigenotoxic and Cytotoxic/Anticytotoxic Effects in Human Lymphocytes
Get PDFLaurocerasus officinalis, a valuable medicinal plant, has rich flavonoid and anthocyanin content, providing benefits for various diseases. It also has ethnopharmacological uses such as diuretics and antidiabetics. Phenolic compounds exhibit their anticarcinogenic effects directly by repairing DNA damage and reducing chromosomal abnormalities. This study aims to investigate genotoxicity/antigenotoxicity and cytotoxicity/anticytotoxicity of L. officinalis extract in human peripheral lymphocytes by the methods of chromosomal aberration (CA), cytokinesis-block micronucleus (CBMN) test, and mitotic index value. The doses of L. officinalis extract were determined as 125, 250, 500, and 1,000 mu g/mL for the genotoxicity test, and mitomycin C (MMC) was added to induce DNA damage for the investigation of antigenotoxicity. In both applications (24 and 48 h), all doses, positive control (MMC) and negative control (sterile dH2O), were used. In CA and CBMN tests for genotoxicity, no significant differences existed between all doses and the solvent control group (p > 0.05). In antigenotoxic activity, doses added with MMC were significantly lower than positive control (p < 0.05). For both the 24-hour and 48-hour periods, the percentage of abnormal cells and the CAs per cell ratio were significantly lower at all L. officinalis extract concentrations compared to the positive control. Additionally, as the treatment concentration increased, the CA ratio showed a decreasing trend. These differences were strongly dose-dependent compared to the positive control (r = -0.799). In all concentrations in the CBMN test, the frequencies were significantly lower than the positive control, and the higher the L. officinalis extract concentrations, the lower the micronuclei (MN). There was a strong dose-dependent relationship in MN formation compared to positive control (r = -0.925). Therefore, L. officinalis extract has no genotoxic effect on human lymphocytes and also has antigenotoxic and protective effect to the damage of MMC. In the mitotic index result, the L. officinalis extract was cytotoxic at only one dose (125 mu g/mL) but anticytotoxic at all other doses against MMC exposure. In conclusion, consuming L. officinalis medicinally benefits and may protect against exposure to genotoxic agents.Sakarya niversitesiSakarya UniversityThis work was financially supported by Sakarya University