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Shifting patterns of pediatric respiratory viruses during the sars-cov-2 pandemic: A retrospective observational study
No full textBackground Respiratory tract infections are a leading cause of hospitalization in patients under 18 years of age and remain a major contributor to pediatric morbidity worldwide. Understanding the epidemiology of viral pathogens-including their seasonal trends and response to global events like pandemics-is essential for public health planning, surveillance strategies, and timely clinical interventions. Methods This retrospective study evaluated the epidemiology and dynamics of respiratory virus detection in hospitalized patients younger than 18 years before and during the SARS-CoV-2 pandemic. Nasopharyngeal swab samples from 1,269 children presenting with respiratory symptoms between November 2018 and October 2021 were tested using multiplex PCR targeting RV/EV, RSV A/B, seasonal coronaviruses, influenza, parainfluenza, hMPV, and other viruses. Results 889 viruses were detected; 579 were single-virus infections, and 143 involved co-infections. RV/EV was the most frequently detected virus in all age groups. RSV was predominant in children under one year, while influenza was more common in older children. The highest testing volume and positivity rates occurred in January. The overall number of tests and positive detections decreased during the pandemic period. RSV, influenza, parainfluenza, and seasonal coronaviruses showed marked declines, whereas RV/EV frequency increased. Conclusions The circulation of pediatric respiratory viruses shifted significantly during the pandemic. Multiplex PCR-based diagnostics proved valuable for tracking these changes, enabling rapid diagnosis and real-time epidemiological insight. These findings underscore the importance of molecular surveillance in managing pediatric respiratory infections, particularly during global health events
Prediction of ammonia mitigation efficiency in sodium bisulfate-treated broiler litter using artificial neural networks
No full textThe increasing demand for poultry meat, driven by its favorable nutritional profile, including low cholesterol and high protein content, has resulted in intensified production volumes and, consequently, elevated ammonia (NH3) emissions. Artificial intelligence-based predictive approaches offer an effective alternative to conventional treatment-oriented methods by enabling faster and more accurate estimation of NH3 removal performance. This study aimed to predict the ammonia removal efficiency of broiler litter generated during a production cycle under controlled laboratory-scale conditions using artificial neural networks (ANNs) trained with different learning algorithms. Four ANN models were developed based on the Levenberg-Marquardt (LM), Fletcher-Reeves (FR), Scaled Conjugate Gradient (SCG), and Bayesian Regularization (BR) algorithms. The results showed that the LM-based model with 12 hidden neurons achieved the highest predictive performance (R2 = 0.9777; MSE = 0.0033; RMSE = 0.0574; MAPE = 0.0833), while the BR-based model with 10 neurons showed comparable accuracy. In comparison with the FR and SCG models, the LM algorithm demonstrated superior predictive accuracy and generalization capability. Overall, the findings suggest that ANN-based modeling is a reliable, data-informed approach for estimating NH3 removal efficiency, providing a potential decision-support framework for ammonia mitigation strategies in poultry production systems
Does ecological anxiety undermine healthy and balanced nutrition while boosting sustainable consumption in young adults? A cross-sectional study of university students
No full textPurpose This study aims to examine the relationship between ecological anxiety levels and sustainable and healthy eating behaviors and sustainable consumption behaviors in young adults. Methods In this cross-sectional study, the data of 689 students studying at X University were evaluated. Data were collected using the Ecological Anxiety Scale, the Sustainable and Healthy Eating Behaviors Scale, and the Sustainable Consumption Behaviors Scale. Results Ecological anxiety showed a negative relationship with Healthy and Balanced Nutrition [Model 1 (beta:-0.086, p < 0.05), Model 2 (beta:-0.079, p < 0.05), and Model 3 (beta:-0.073, p < 0.05)]. Ecological anxiety showed a positive relationship with Environmental Awareness [Model 1 (beta: 0.077, p < 0.05), Model 2 (beta: 0.083, p < 0.05), and Model 3 (beta: 0.088, p < 0.05)] and Reusability [Model 1 (beta: 0.107, p < 0.05), Model 2 (beta: 0.100, p < 0.05), and Model 3 (beta: 0.100, p < 0.05)]. Conclusions Overall, ecological anxiety was associated with lower levels of healthy and balanced nutrition, but with higher levels of sustainable consumption behaviors, particularly environmental awareness and reusability
Uncertainty assessment of the impacts of climate change on streamflow in the Iznik lake watershed, Türkiye
No full textStudy region: This study focused on the Iznik Lake Watershed in northwestern T & uuml;rkiye. Study focus: Climate change is increasingly affecting water resources worldwide, raising concerns about future hydrological sustainability. This study investigates the impacts of climate change on river streamflow in the Iznik Lake Watershed, a critical freshwater resource in northwestern T & uuml;rkiye. To capture possible future conditions, downscaled climate projections were integrated with the SWAT+ hydrological model. Recognizing the inherent uncertainties in climate models and model parameterization, the analysis examined the relative influence of climate realizations, emission scenarios, and hydrological parameters on streamflow outputs. By quantifying both the magnitude of climate-induced changes and the contribution of different sources of uncertainty, the study provides insights that can guide decision-makers in future management planning and be useful for forthcoming modeling efforts. New hydrological insights for the region: Projections indicate wetter winters and springs but drier summers, with an overall warming trend in the study area. Based on simulations driven by four representative grid points, the results at the Karadere station, which represents the main inflow of the watershed, indicate modest changes in mean annual streamflow, ranging from -7% to +56% in the near future and from +19% to +54% in the far future. Maximum flows (Qmax) exhibit notable increases, ranging from +0.9% to +47% in the near future and from +21% to +63% in the far future, indicating a tendency toward higher peak discharges under future climate conditions. Low-flow conditions, especially in summer, exhibit the greatest relative variability due to near-zero baseline discharges. Relative change analysis revealed considerable differences in Karadere and Findicak sub-catchments, reflecting heterogeneous hydrological responses even within the same basin. Uncertainty analysis, conducted using both an ANOVA-based approach and Bayesian Model Averaging (BMA), highlighted the dominant influence of climate projections and potential evapotranspiration calculation methods, while land use change contributed negligibly to overall uncertainty.Norwegian University of Science and Technology (NTNU
Cognitive semantics analysis on the conception of time in teaching Turkish as a foreign language books
No full textBu araştırmada yabancı dil olarak Türkçe öğretimi amacıyla hazırlanan Yedi İklim, Yeni Hitit ve Gazi TÖMER ders kitaplarının B2 ve C1 düzeylerinde öğrenicinin alımlama becerilerine yönelik hazırlanan metinlerde zaman kavrayışının temsil biçimi, bilişsel dilbilim çerçevesinde incelenmiştir. Toplam 27.658 tümceden oluşan veri seti metafor, metonimi ve metaftonimi kategorileri üzerinden çözümlenmiştir. Zamanın kavramsal odakları, kaynak alanları ve işlevsel kullanımları belirlenmiştir. Bulgular, zaman kavrayışının ağırlıklı olarak kavramsal odaklar üzerinden kurgulandığını göstermektedir. En sık rastlanan metonimik odaklar TAKVİMZAMAN ve OLAY-ZAMAN olurken, MEVSİM-ZAMAN ve NESNE-ZAMAN odakları daha
düşük oranlarda yer almıştır. Zamanın işlevsel kullanımlarında ise süre, değerleme ve retorikanlatı kategorilerinin öne çıktığı ve modalite-olasılık, kesinlik-belirsizlik, sıklık işlevlerinin daha sınırlı düzeyde yer aldığı tespit edilmiştir. Yabancı dil olarak Türkçe öğretimi için hazırlanan kitap setlerinden Yedi İklim, zaman kavramını metafor ve metonimi açısından en yüksek yoğunlukta sunmaktadır. HAREKET-YOL ve NESNE-ARAÇ gibi somut şemalarla öğrenenlere yapısal olarak tutarlı ve kavramsal açıdan zengin biçimde zaman tasarımı sağlayan materyal olarak öne çıkmaktadır. Gazi TÖMER seti, metafor ve metonimi kullanımında orta düzeyde ve dengeli, metaftonimik de ise en yüksek düzeyde görünüm sergilemektedir. Zamanın olay, takvim ve eylem odaklı metonimik örgü içinde, işlevsel ve ritmik yönlerine eğilimli zaman modeli sunduğu düşünülmektedir. Yeni Hitit setinde ise metafor, metonimi ve metaftonimi yoğunluğu görece en düşük düzeydedir. Temel kavramsal şemalara dayalı, kronolojik ve kültürel bağlama odaklanan tutarlı ve kontrollü zaman kavrayışı sunulmaktadır. B2 düzeyinde zamanın anlatısal ve deneyimsel bağlamlarda kullanıldığı, C1’de ise soyutlaştırma düzeyinin arttığı ve kültürel kodların belirginleştiği belirlenmiştir. Sonuç olarak çalışma, zaman kavrayışının Türkçe öğretim materyallerinde kültürel ve bilişsel düzeyde çok katmanlı yapı sunduğunu ortaya koymaktadır.This study examines the representation of time perception in the texts prepared for teaching Turkish as a foreign language at the B2 and C1 levels in the Yedi İklim, Yeni Hitit, and Gazi TÖMER textbooks, within the framework of cognitive linguistics. The book sets, consisting of 27,658 sentences, were analyzed through the categories of metaphor, metonymy, and metaphtonymy. The findings show that the understanding of time is predominantly constructed through conceptual focuses. The most frequently encountered metonymic focuses were CALENDAR-TIME and EVENT-TIME, while SEASON-TIME and OBJECT-TIME focuses were present at lower rates. In the functional uses of time, the categories of duration, evaluation, and rhetoric-narrative were prominent, while the functions of modality-probability, certaintyuncertainty, and frequency were found to be more limited. Among the book sets prepared for teaching Turkish as a foreign language, the Yedi İklim set presents the concept of time with the highest intensity in terms of metaphor and metonymy. It stands out as a material that provides learners with a structurally consistent and conceptually rich understanding of time through concrete schemas such as MOVEMENT-PATH and OBJECT-TOOL. The Gazi TÖMER set exhibits a moderate and balanced level of metaphor and metonymy use, while exhibiting the highest level of metonymy. It is thought to offer a time model that leans towards the functional and rhythmic aspects of time within a metonymic framework focused on events, calendars, and actions. In the Yeni Hitit set, the intensity of metaphor, metonymy, and metonymy is relatively low. It offers a consistent and controlled understanding of time based on basic conceptual schemas and focusing on chronological and cultural context. It was determined that at the B2 level, time is used in narrative and experiential contexts, while at the C1 level, the level of abstraction increases and cultural codes become more prominent. In conclusion, the study reveals that the understanding of time in Turkish teaching materials presents a structure at the cultural and cognitive levels
A parametric study on laser-assisted preheating and post-weld heat treatment to enhance the mechanical properties of AISI 1075 high-carbon steel for electric vehicle manufacturing applications
No full textElectric vehicles (EVs) are a major step toward sustainable mobility, primarily by reducing emissions and improving energy efficiency. In this context, material selection is crucial for ensuring durability, recyclability, and minimizing environmental impact. Although composite materials are effective in reducing weight, their limited recyclability remains a significant challenge. In contrast, high-carbon steels such as AISI 1075, offering high strength, wear resistance, recyclability, and cost-effectiveness, can be a promising alternative to ultra-high strength steel (UHSS) and composite materials. However, the welding of high-carbon steels like AISI 1075 is susceptible to brittleness and welding defects. Laser welding and laser heat treatment have been recognized as effective methods to overcome these limitations. This study investigates the feasibility of laser welding for AISI 1075, with a particular focus on the effects of laser-based pre-weld heating (PH) and controlled post-weld heat treatment (PWHT) on the macro-structure and mechanical properties. These methods improve the internal structure while offering significant energy and time savings compared to conventional techniques. A thermal camera and a Time-Temperature-Transformation (TTT) diagram were utilized to optimize laser parameters and monitor cooling. Additionally, mechanical tests, including tensile and hardness testing, were conducted to assess the mechanical properties of the welded specimens. The findings highlight the critical role of pre-weld heating and post-weld heat treatment in improving the weldability of high-carbon steels. This study provides a structured framework for implementing laser welding and heat treatment as sustainable and cost-effective manufacturing solutions for EV applications
Effect of corchorus olitorius extract on physical properties of and antioxidant activities of chitosan/gelatin biocomposite films
No full textWound healing is a complex physiological process that requires an optimal moist and antibacterial environment to promote tissue regeneration. In this study, chitosan/gelatin (CG) biocomposite films incorporated with different concentrations of Corchorus olitorius (C. olitorius) extract (2.5-10% v/v) were fabricated via the solvent casting method. The effects of extract loading on the structural, thermal, mechanical, optical, and biological characteristics of the films were systematically investigated. The tensile strength of the films decreased from 5.95 +/- 1.70 MPa to 1.74 +/- 0.20 MPa, while the elongation at break increased up to 110.5 +/- 9.8%. Contact angle measurements showed enhanced hydrophilicity with the highest extract content (56.4 degrees +/- 4.8 degrees). The incorporation of the extract also led to a notable reduction in transparency (from 7.18% to 2.57%) and a slight decrease in thermal stability. FT-IR spectra confirmed physical interactions, mainly hydrogen bonding, between the polymer matrix and the extract components. Furthermore, the 10% (v/v) C. olitorius-containing film exhibited significant antioxidant activity (80.5% DPPH scavenging) and antibacterial efficiency with inhibition zones of 9 mm against E. coli and S. aureus. These results indicate that the developed chitosan/gelatin/C. olitorius biocomposite films possess favorable physical and biological properties, suggesting their strong potential for wound dressing and biomedical applications
A participatory model with children and architecture students to design loose parts
No full textIn recent years, many participatory design projects are conducted with children to develop playgrounds that meet needs and expectations of children. In studies related to playgrounds, while there is an observed desire among children to play with loose parts, no participatory studies regarding the design of loose parts have been found. However, loose parts play have many benefits on cognitive, physical, social, and emotional development of children. In this context, the scientific research project titled "Participatory Design of Loose Parts for Play in Urban Spaces" was carried out in collaboration with Bursa Nil & uuml;fer Municipality, Nil & uuml;fer City Council, and Bursa Uludag University in T & uuml;rkiye. The aim of the article is to discuss a participatory design model in which children and architecture students design loose parts, within the framework of the benefits of co-preparation, co-working, co-design, co-motivation, and co-learning. The method of the study is based on qualitative data collection methods including observation, video, photo recordings, and notes from individual and group interviews and surveys with children and architecture students. As a result, it was observed that the participatory design model enabled children and architecture students to collaboratively develop design ideas for loose parts. It is predicted that the model can be adapted and used in different contexts and design processes
Postbiotics and nicotinamide utilize distinct mechanisms to improve skin barrier integrity, inflammation, and keratinocyte differentiation
No full textThe modulation of immune responses and tissue regeneration by postbiotics is a rapidly advancing area in skin care. Here, we show that whole-cell postbiotics derived from Bifidobacterium breve, Limosilactobacillus reuteri, and Ligilactobacillus salivarius, along with nicotinamide (NAM), enhance keratinocyte growth, differentiation, and skin epithelial barrier integrity in ex vivo human skin, as determined by electrical impedance spectroscopy (EIS), multiomics, and machine learning. B. breve promoted keratinocyte differentiation and suppressed inflammatory pathways, while L. reuteri and L. salivarius primarily reduced inflammatory pathways. Although NAM downregulated keratinocyte differentiation, it exerted anti-inflammatory effects. Machine learning analyses linked EIS changes to certain genes, highlighting strain-specific mechanisms. In addition, B. breve, L. reuteri, and NAM mitigated a common skin cleanser-induced skin epithelial damage, further supporting their therapeutic potential. In conclusion, integrating skin barrier measurements with omics and machine learning enabled the dissection of essential anti-inflammatory and keratinocyte differentiation mechanisms and genes of a strengthened skin barrier
Educational leadership and social justice: A hybrid systematic review
No full textThis study examines scholarly articles on social justice-oriented educational leadership published between 2000 and 2024, tracing the field's conceptual evolution, theoretical foundations, and key thematic trends. Employing a hybrid systematic review approach that integrates quantitative bibliometric mapping with qualitative thematic synthesis, it investigates core theories underpinning this leadership paradigm and the challenges of translating theory into practice. Unlike prior reviews that relied on either bibliometric or narrative approaches, this study combines both, offering a historical mapping alongside a thematic interrogation of 20 influential works. Its main contribution lies in the thematic analysis, which reveals how structural, political, and ethical constraints are theorized across contexts, moving the field beyond descriptive mapping toward critical synthesis. Drawing on 25 years of publications from Scopus and Web of Science, findings show significant growth in the field and increasing attention to ethical, cultural, structural, and political dimensions. The study underscores that effective educational leadership must address systemic inequalities, while highlighting policy constraints that limit the enactment of social justice principles and calling for equity-centered reforms