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Novel eco-friendly approach employing recycled waste ferrochrome slag in cellulose-based bioconductive paper production: Energy harvesting and electro-optical properties
Get PDFThis pioneering research incorporates ferrochrome slag (FS), a byproduct of metal extraction, with recycled pulp paper to improve electrical conductivity in an environmentally acceptable manner. The alternating current (AC) electrical conductivity exhibited consistent behavior from 100 Hz to 5 MHz at room temperature. A remarkable twofold increase in conductivity was achieved by elevating the FS ratio from 20 % to 25 % in the direct current region. Distinct trends were evident in 's' values, which serve as a measure of the level of interaction between mobile ions and their surroundings across frequency segments. The AF-Region (100 Hz - 2 kHz) yielded 's' values of 0.627-0.640, preferring values below 1, while the LRF-Region (2 kHz - 90 kHz) yielded values of 1.74-1.77, preferring values above 1. The sample with FS 25 % showed heightened conductive potential. Capacitance values and real permittivity (epsilon') increased noticeably at 100 Hz and 1 kHz with higher FS doping rates. By evaluating physical, optical, mechanical, electrical, and morphological properties, this study reveals the latent potential of FS integration, advancing electrical conductivity through an eco-friendly approach. This unique waste valorization underscores FS as a game-changing material for paper production leading to further environmental perspectives
Building detection with segformer models
Get PDFDepremler, altyapı ve üstyapılarda ciddi hasarlara yol açarak toplumları olumsuz etkileyen doğal afetlerdir. Deprem sonrası bina tespiti, doğru ve hızlı müdahaleler için kritik öneme sahiptir. Bu çalışmada bina tespitinde SegFormer modellerinin performansını değerlendirmek amacıyla 2017 Meksika Depremi ve 2023 Hatay Depremi'ne ait uydu görüntüleri kullanılmıştır. SegFormer modeli, nesnelerin piksel düzeyinde segmentasyonu için geliştirilmiş bir derin öğrenme yöntemidir. Çalışmada, SegFormer'ın B0,B1,B2,B3,B4 ve B5 modelleri, semantik segmentasyon görevinde test edilmiş, Meksika ve Hatay veri setlerinde kapsamlı analizler gerçekleştirilmiştir. Veri setleri, ortak çözünürlüğe dönüştürülmüş, segmentasyon maskeleri oluşturulmuş ve modeller eğitim sürecinde doğruluk, kayıp ve segmentasyon başarısı gibi metriklerle değerlendirilmiştir. Elde edilen sonuçlara göre, SegFormer B4 modeli, Meksika veri setinde 0,8528 doğruluk, 0,7996 geri çağırma, 0,7395 mAP, 0,6824 IoU ve 0,8001 Dice katsayısı ile en başarılı model olmuştur. Bu model, büyük binaların sınırlarını doğru şekilde belirleme ve segmentasyon maskelerinin tutarlılığı açısından diğer modellere göre daha başarılıdır. Hatay veri setinde ise B4, 0,7906 doğruluk, 0,5933 Dice katsayısı ve 0,4280 IoU ile görece dengeli bir performans göstermiştir. B0 modeli diğer modellere göre düşük başarı göstermiştir. Karmaşık yapısına rağmen, B5 modeli küçük detayların tespitinde başarısız olmuştur. Çalışmada SegFormer B4 modelinin bina segmentasyonunda etkili olduğu görülmüş ve gelecek araştırmalar için veri seti optimizasyonunun önemi vurgulanmıştır. Anahtar Sözcükler: Bina Segmentasyonu, SegFormer, Derin Öğrenme, Bina Tespiti, Deprem Analizi, Veri GörselleştirmeEarthquakes are natural disasters that significantly impact societies by causing severe damage to infrastructure and superstructures. Post-earthquake building detection is critical for accurate and rapid interventions. This study evaluates the performance of SegFormer models in building detection using satellite images from the 2017 Mexico Earthquake and the 2023 Hatay Earthquake. SegFormer is a deep learning method developed for pixel-level segmentation of objects. In the study, SegFormer models B0, B1, B2, B3, B4, and B5 were tested in semantic segmentation tasks, and comprehensive analyses were conducted on the Mexico and Hatay datasets. The datasets were standardized to a common resolution, segmentation masks were generated, and the models were evaluated during the training process using metrics such as accuracy, loss, and segmentation performance. The results indicate that the SegFormer B4 model performed best on the Mexico dataset, achieving 0,8528 accuracy, 0,7996 recall, 0,7395 mAP, 0.6824 IoU, and 0.8001 Dice coefficient. This model outperformed others in accurately delineating the boundaries of large buildings and maintaining consistency in segmentation masks. On the Hatay dataset, the B4 model demonstrated relatively balanced performance, with 0,7906 accuracy, 0,5933 Dice coefficient, and 0,4280 IoU. The B0 model showed lower performance compared to the others, while the B5 model, despite its complexity, struggled with detecting small details. The study concludes that the SegFormer B4 model is effective for building segmentation and emphasizes the importance of dataset optimization for future research
Geometry of Kenmotsu Manifolds via Q-Curvature Tensor and Schouten–Van Kampen Connection.
Get PDFThis research paper aims to study the Q-curvature tensor on Kenmotsu manifolds endowed with the Schouten–van Kampen connection. Using the Q-curvature tensor, whose trace is the well-known Z-tensor, we characterized Kenmotsu manifolds by introducing the notion of ?-Q flat and ?-Q flat manifolds and novel tensor conditions, such as Q(?,X)Q=0, Q(?X)R=0, Q(?,X)S=0, Q(?,X)C=0 ,Q(?,X)H=0, and Q(?,X)P=0, with the Schouten–van Kampen connection. To validate some of our results, we constructed a non-trivial example of Kenmotsu manifolds endowed with the Schouten–van Kampen connection
Spatial analysis of the macroeconomic determinants of crime: Evidence from regions of Türkiye
Get PDFThis study investigates the macroeconomic and spatial determinants of crime rates in Türkiye by employing spatial panel data models. Using annual data from 12 NUTS-1 regions over the period 2009–2022, the analysis examines the effects of unemployment rate, income inequality (Gini coefficient), inflation rate, per capita income (GDP), public education expenditures, and urbanization on crime rates. Recognizing the spatial dependence structure of regional data, spatial error models are preferred over classical panel estimators. In addition to total crime, the study disaggregates crime data into two major categories—assault and theft—to assess the robustness of results and explore type-specific dynamics. The findings reveal that income inequality, per capita income, and inflation have positive and statistically significant effects on crime rates across all models. While public education expenditures do not exhibit a significant direct effect, their spatially lagged values show a negative and significant relationship with both total and disaggregated crime categories. The urbanization variable is found to reduce theft rates, although its effect on assault is weaker and not consistently significant. The unemployment rate does not appear to be a significant determinant in most specifications. These results highlight the importance of spatially informed, region-specific crime prevention strategies. In particular, the findings emphasize the relevance of interregional spillover effects of education policy and the differentiated impact of urbanization on distinct types of crime. The study contributes to the literature by offering both empirical and methodological advancements through the use of disaggregated crime data and spatial econometric techniques. © 2025 Elsevier B.V., All rights reserved
Predictive value of nutritional scores in non-valvular atrial fibrillation patients: Insights from the AFTER-2 study
Get PDFBackground and aim: Many scoring systems are used to evaluate malnutrition, but there is no consensus on which scoring system would be more appropriate. We aimed to investigate the effect of malnutrition in patients with non-valvular atrial fibrillation (NVAF) and to compare three scoring systems. Methods and results: A total of 2592 patients with non-valvular AF from 35 different centers in Turkey were included in this prospective study. All participants were divided into two groups: 761 patients who died and 1831 patients who were alive. The malnutrition status of all participants was evaluated with three scoring systems. The primary outcome was all-cause mortality. The mean age of the population was 68.7 +/- 11.1 years, and 55.5 % were female. According to Cox regression analysis, the geriatric nutritional risk index (GNRI) (HR = 0.989, 95 % CI: 0.982-0.997, p = 0.007), controlling nutritional status (CONUT) score (HR = 1.121, 95 % CI: 1.060-1.185, p < 0.001), and prognostic nutritional index (PNI) (HR = 0.980, 95 % CI: 0.962-0.999, p = 0.036) were found to be significant mortality predictors. ROC curve analysis indicated GNRI (AUC = 0.568), CONUT (AUC = 0.572), and PNI (AUC = 0.547) had moderate predictive values. Kaplan-Meier analysis showed that increasing the risk class based on GNRI (p < 0.001) and CONUT (p < 0.001) was associated with decreased survival, while PNI staging had no statistically significant effect (p = 0.266). Conclusions: Malnutrition, determined by three scoring systems, was found to be an independent predictor of all-cause mortality in NVAF patients. Nutritional examination may provide useful information for prognosis and risk stratification in patients with NVAF
To be, or not to be, a non-native species in non-English languages: gauging terminological consensus amongst invasion biologists
Get PDFIn invasion biology, terminological frameworks contribute to the improvement of effective communication among scientists, stakeholders, and policy-makers. This is important not only for informing policy decisions but also for engaging the broader public in understanding the risks associated with biological invasions. Meanwhile, the role of non-English languages in advancing knowledge in invasion biology has gained momentum in recent years. Building on the seminal contributions in this scientific discipline by Professor Gordon H. Copp, this paper examines the provision of three key terms defining species invasiveness in 28 non-English languages. We first define the three non-redundant terms “non-native species”, “established species”, and “invasive species”. Through a comparative analysis of the equivalent of these terms in the 28 non-English languages, as contributed by our panel of invasion biologists and native speakers, with those in a reference review paper, and following the diffusion-of-English versus ecology-of-language paradigms, we identify discrepancies and nuances reflecting the dynamic nature of terminology in invasion biology. While some languages showed consensus in terminology, others differed due to either the avoidance of a culturally or politically laden term for “non-native” or the achievement of greater precision in meaning. Our findings highlight the requirement for clear and precise terminology in invasion biology and suggest the adoption of multidisciplinary approaches to reach consensus and facilitate communication amongst scientists, policy-makers, and the general public in a globally interconnected and rapidly changing world. This will enhance international collaboration and accelerate knowledge exchange, leading to more effective management of biological invasions. © 2025 Elsevier B.V., All rights reserved
A reliability and validity study of professional development models tendency scale
Get PDFThe aim of this study is to develop a valid and reliable measurement tool to identify teachers' tendencies towards professional development models. In line with the purpose of scale development, a survey model was preferred. The scale was designed to be applicable to teachers from various disciplines currently working in any institution (preschool, primary, secondary, and high school levels). The study sample comprises teachers working in public schools from various districts. During the scale development process, Exploratory Factor Analysis (EFA) was initially conducted, followed by Confirmatory Factor Analysis (CFA). EFA was performed with data from 408 participants, while CFA was conducted with data from 260 participants. As a result of the analyses, a scale consisting of 4 factors and 31 items was obtained. The sub-factors of the scale were named as “Tendency towards observation-based professional activities, Belief in collaboration with colleagues, Participation in collaborative activities, and Resistance to observation and supervision.” The Cronbach's Alpha reliability coefficient of the scale was determined to be 0.94. The relationships between the scale factors were examined by calculating Pearson correlation coefficients. Moderate to high positive and significant correlations were found between the total score obtained from the scale and its factors. The findings revealed that the scale demonstrated a satisfactory level of internal consistency, indicating its validity and reliability. Accordingly, the scale was designated as the "Professional Development Models Tendency Scale.". © 2025 Elsevier B.V., All rights reserved
A new method for the determination of Brilliant Blue FCF in energy drinks: Smartphone digital imaging colorimetry (SDIC) and green deep eutectic solvent-based dispersive microextraction procedure
Get PDFSmartphone digital image colorimetry, coupled with a deep eutectic solvent-based liquid-liquid microextraction, was used to determine the Brilliant Blue FCF colorant in energy drinks. The Brilliant Blue FCF determination using the smartphone digital image colorimetry (SDIC) method offers several advantages, including fast and practical application, low cost, and high efficiency. Colorimetric determinations were performed using the “RGB Color Detector” application. DES was obtained by mixing tetrabutylammonium chloride (TBAC) with decanoic acid (DecA) in a 1:2 ratio. The optimum conditions for microextraction were a pH of 5.0, a DES volume of 300 μL, a sample volume of 15 mL, an ultrasonic time of 2 min, and a centrifuging time of 3 min at 4000 rpm. The LOD and LOQ values for the technique were determined to be 0.001 μg mL−1 and 0.003 μg mL−1, respectively. The RSD was determined to be 2.54 % for intraday measurements and 3.04 % for interday measurements. The correlation coefficient was 0.9996, indicating that acceptable linearity was attained. Additionally, the developed microextraction method has been demonstrated to comply with green chemistry principles by applying the Green Analytical Procedure Index (GAPI) tool. © 2025 Elsevier B.V., All rights reserved
The use of science activities based on educational escape game in the development of problem solving skills: A mixed-method action research
Get PDFBu araştırmada, eğitsel kaçış oyununa dayalı fen etkinliklerinin, okul öncesi öğrencilerinin problem çözme becerilerini geliştirmede kullanımı incelenmiştir. Araştırma Düzce ilinin Gölyaka ilçesindeki bir devlet anaokulunda gerçekleştirilmiştir. Araştırmanın katılımcıları 4'ü kız, 4'ü erkek olmak üzere 8 beş yaş (60-72 aylık) grubundaki öğrenciden oluşmaktadır. Araştırma karma yöntem yaklaşımına dayalı eylem araştırması deseni kullanılmıştır. Araştırmada veriler problem çözme becerisi ölçeği (PÇBÖ), araştırmacı günlüğü, fotoğraf ve video kayıtları, yarı yapılandırılmış öğrenci görüşme formları, yarı yapılandırılmış uzman gözlem ve değerlendirme formları, öğrenci ürünleri kullanılarak toplanmıştır. Araştırmada okul öncesi öğrencilerinin problem çözme beceri düzeylerinin belirlenmesinde Problem Çözme Becerisi Ölçeği kullanılmıştır. Problem Çözme Becerisi Ölçeği'nin güvenirlik katsayısı 0.86'dır.Verilerin analizinde, öğrencilerin problem çözme becerileri düzeylerinin tespitinde betimleyici istatistikten yararlanılmıştır. Eğitsel kaçış oyununa dayalı fen etkinliklerinin öğrencilerin problem çözme becerilerine etkisinin analizinde Wilcoxon İşaretli Sıralar testi kullanılmıştır. Araştırmadan elde edilen nicel bulgular, eğitsel kaçış oyununa dayalı fen etkinliklerinin okul öncesi öğrencilerinin problem çözme becerilerinde istatistiksel olarak anlamlı bir artış sağladığını ortaya koymuştur. Problem çözme becerilerine ilişkin nitel sonuçlar, öğrencilerin problem durumlarını çok boyutlu ve farklı perspektiflerden ele alarak çeşitli çözüm önerileri geliştirdiklerini göstermektedir. Bu sonuç, öğrencilerin yaratıcı problem çözme becerilerinde anlamlı bir gelişim yaşadıklarına işaret etmektedir. Karma yöntemle gerçekleştirilen bu eylem araştırması kapsamında, öğrencilerin eğitsel kaçış oyununa dayalı fen etkinliklerine katılım sırasında kendilerini mutlu hissettikleri belirlenmiştir. Zaman kısıtlaması, oyunun eğlenceli yapısı, farklı tasarlanmış sınıf ortamı, materyaller, pekiştireç kullanımı ve grup çalışması gibi unsurların, öğrencilerin etkinliğe yönelik olumlu tutum geliştirmelerine katkı sunduğu saptanmıştır. Bununla birlikte, problem durumlarının niteliği, kullanılan materyaller ve sınıf ortamının yapısı öğrenciler tarafından zorlayıcı unsurlar olarak değerlendirilmiştir. Ayrıca öğrencilerin, yeni bir eğitsel oyun tasarımında farklı oyun modellerine ve ilgi alanlarına uygun ödüllere yönelik beklentilerinin bulunduğu sonucuna ulaşılmıştır. Öğrenci görüşleri genel olarak problem çözme becerilerinde bir gelişme yaşandığını desteklemektedir. Araştırmacı ve uzman görüşlerine göre, eğitsel kaçış oyunlarının okul öncesi eğitim düzeyine uygun olduğu, fen temalarının oyunu ilgi çekici kıldığı ve öğrencilerin süreçte aktif katılım yoluyla iş birliği geliştirdiği sonucuna varılmıştır. Bu doğrultuda, eğitsel kaçış oyununa dayalı fen etkinliklerinin okul öncesi eğitimde etkili bir öğretim yöntemi olarak kullanılabileceği ileri sürülmektedir.In this study, the use of science activities based on educational escape game in developing problem solving skills of preschool students was investigated. The research was conducted in a state kindergarten in Gölyaka district of Düzce province. The participants of the study consisted of 8 five-year-old (60-72 months) students, 4 girls and 4 boys. The research used action research design based on mixed method approach. The data were collected using the problem solving skills scale (PSS), researcher diary, photographs and video recordings, semi-structured student interview forms, semi-structured expert observation and evaluation forms, and student products. In the study, the Problem Solving Skill Scale was used to determine the problem solving skill levels of preschool students. The reliability coefficient of the Problem Solving Skill Scale is 0.86. In the analysis of the data, descriptive statistics were used to determine the problem solving skill levels of the students. Wilcoxon Signed Ranks test was used to analyse the effect of science activities based on educational escape game on students' problem solving skills. The quantitative findings of the study revealed that educational escape game-based science activities provided a statistically significant increase in preschool students' problem solving skills. The qualitative results related to problem solving skills show that students developed various solution proposals by addressing problem situations from multidimensional and different perspectives. This result indicates that students experienced a significant improvement in their creative problem solving skills. Within the scope of this mixed-method action research, it was determined that students felt happy during participation in science activities based on the educational escape game. Factors such as time limitation, fun nature of the game, differently designed classroom environment, materials, use of reinforcers and group work were found to contribute to students' positive attitudes towards the activity. However, the nature of the problem situations, the materials used and the structure of the classroom environment were evaluated as challenging factors by the students. In addition, it was concluded that students had expectations for different game models and rewards suitable for their interests in a new educational game design. Student opinions support that there is an improvement in problem solving skills in general. According to the researcher and expert opinions, it was concluded that educational escape games are suitable for preschool education level, science themes make the game interesting and students develop cooperation through active participation in the process. In this direction, it is suggested that science activities based on educational escape games can be used as an effective teaching method in preschool education
Role of Transcranial Doppler Ultrasonography in Detecting and Excluding Ischemic Stroke in the Emergency Department: A Prospective Observational Study
Get PDFIntroduction: To determine whether color doppler ultrasonography (CDUS) and transcranial Doppler ultrasonography (TCD) can be used as an alternative test to cranial computed tomography angiography (CTA) by detecting vascular occlusions at the bedside in the emergency department (ED). Methods: This is a prospective, observational, and single-center study. It was performed on patients aged 18 years and older who were examined with a preliminary diagnosis of ischemic stroke and presented to an ED within the first 48 hours after the onset of symptoms. TCD, CDUS and vertebral artery doppler ultrasound were performed on one hundred and three patients. Computed tomography angiography was conducted as well and TCD and CDUS findings were compared. Results: Over one month, thirty-three patients were included in the study. The median age of the patients was 67 (52.5-78), and 57.6% (n=19) were male. When the TCD findings were compared with the gold standard (CTA), the negative predictive value of TCD for middle cerebral artery (MCA) was 96.5%. Both right and left carotids could be visualized optimally in all patients with CDUS. In the vertebral artery ultrasound examination, the right and left vertebral arteries were optimally visualized in all patients. Left vertebral artery ultrasound and CTA findings were completely compatible. Conclusion: Transcranial Doppler ultrasonography, a fast, inexpensive, non-invasive, and reproducible method, may have a role in the early detection or exclusion of ischemic strokes where time is critical. This suggests that TCD may be a helpful method in the ED for the early exclusion of acute MCA occlusions