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Sericin and gentamicin-enhanced polyurethane-acrylate adhesives for superior adhesion, biocompatibility and antibacterial property
No full textBioadhesives are crucial in minimally invasive procedures but often lack biocompatibility, mechanical strength, and antimicrobial properties. Polyurethane-based adhesives, particularly UV-curable types, offer tunable properties and rapid curing. This study developed a polyurethane-acrylate adhesive system incorporating sericin and gentamicin to enhance biocompatibility and antibacterial effects for surgical and wound care applications. Sericin, a silk-derived protein, improved cell adhesion without compromising structural integrity, while 2.5 % gentamicin provided sustained antibacterial activity against E. coli, P. aeruginosa, and S. aureus. The synthesis involved modifying IPDI with beta-cyclodextrin, sericin, and PEG (200, 400, 600) to optimize flexibility and stability. Comprehensive characterization was conducted, including FTIR, TGA, DSC, NMR, SEM, AFM, adhesion strength, biodegradability, gentamicin release, antibacterial efficacy, and biocompatibility with L-929 fibroblast cells. Adhesion strengths were 4141.3-4474.7 kPa (PEG200), 2306-3158 kPa (PEG400), and 1690-2061 kPa (PEG600), with PEG400 providing the best balance, making IPDI-SER-P400-20-AC the optimal candidate. The adhesive exhibited 87 % cell viability (ISO 10993-5), 30 % biodegradation in four weeks, and 60 % gentamicin release within 24 h, ensuring rapid antibacterial action. This sericinand gentamicin-enhanced bioadhesive offers a promising multifunctional platform for biomedical applications, with potential for further optimization in controlled drug release and long-term in vivo evaluations
Investigation of the critical buckling load of a column with linearly varying moment of inertia using analytical, numerical, and hybrid machine learning approaches
No full textThis study investigates the buckling behavior of columns with variable cross-sections using analytical, numerical, and hybrid machine learning (ML) approaches. Initially, the power series method is employed to calculate the buckling loads of columns with both constant and varying cross-sections under diverse boundary conditions. Then a finite element (FE) analyses of the columns are performed to obtain the buckling loads and the results are validate by comparing them with results from power series method. Once validated, the FE model is used to generate a large dataset encompassing a wide range of cross-sections, lengths, and material properties, as per the samples obtained through the Sobol sampling method. A hybrid ML model is then developed by integrating the XGBoost algorithm with the particle swarm optimization (PSO) technique for hyperparameter tuning. This hybrid PSO-XGBoost model is trained to predict the buckling loads of columns with varying cross-sections. Its performance for input parameters outside the training dataset is evaluated using statistical metrics and scatter plots. The results demonstrate excellent agreement between the FE analysis and the power series method, confirming the reliability of both approaches. The PSO-XGBoost model achieved remarkable predictive accuracy, with R2 values of 0.999 and 0.996 for the training and testing datasets, respectively. Furthermore, SHapley Additive exPlanations (SHAP) analysis is conducted to explore the influence and interactions of input parameters on buckling loads, providing valuable insights into the model's interpretability and the underlying mechanics of column buckling
Primary neuroendocrine tumors of the breast according to the WHO 2019 classification; real life experiences of rare tumor types of the breast
No full textBackground Neuroendocrine neoplasms (NEN) originate in many body parts, with 70% reported from the gastrointestinal system, 25% from the lungs. NENs of the breast account for = 70 years, PR positivity, and tumor size. A low ECOG PS, younger age, breast-conserving surgery (BCS), and small tumor diameter were associated with better survival. A low ECOG PS, early stage, BCS, and fewer than 4 malignant lymph nodes were associated with better disease-free survival. All the patients in this study were at an early stage and were treated for typical breast cancer, although some patients diagnosed with neuroendocrine carcinoma (NEC) received cisplatin and etoposide treatment. Conclusions In our study, the prognosis of breast NEN patients was better than the literature data. Maybe the prognosis of patients evaluated as breast NEN according to the new classification is better than the older classification groups
Determination of the responses of native black carrot genotypes to salt stress during seed germination
No full textBüyük bir stres faktörü olan tuzluluk dahil abiyotik stres faktörleri, çimlenme, fide büyümesi ve bitki gelişimini önemli ölçüde etkilemektedir. Bu çalışmada, iki yerli havuç genotipi (Ereğli ve Hatay Siyahı) ve bir ticari turuncu havuç genotipinde (Dragon) tuzluluk toleransı incelenmiş ve çimlenme aşamasında tuzluluk toleranslarındaki değişim araştırılmıştır. Değişen NaCl konsantrasyonlarında (50, 100, 150 ve 200 mM), çimlenen tohum sayısı, plumula uzunluğu, radikula uzunluğu, iyon sızıntısı ve yaprak pigmentleri ölçülmüştür. Tuzluluk stresi; çimlenme yüzdesinde, kökçük ve plumula uzamasında, çimlenme hızında, çimlenme indeksinde ve fide gücü indeksinde belirgin bir azalmaya yol açmıştır. Bununla birlikte yerli siyah köklü havuç genotipleri, turuncu köklü havuç genotipine kıyasla yüksek NaCl seviyelerine karşı daha iyi tepki göstermiştir. 200 mM NaCl’de tüm genotiplerin çimlenmesi ciddi şekilde engellenmiştir. Sonuçlar, tuzluluk seviyesi yükseldikçe turuncu köklü genotipten daha iyi tolerans gösteren siyah köklü genotipler dahil tüm genotiplerde çimlenme özelliklerini azalttığını göstermiştir. Bununla birlikte artan tuzluluk konsantrasyonları klorofil b, karotenoidler, antosiyanin ve likopen konsantrasyonları artan NaCl konsantrasyonu ile birlikte tüm genotiplerde artmıştır. Benzer sonuçlar kökten elde edilen iyon sızıntısında da gözlenmiştir. Bu sonuç, antosiyanin açısından zengin genotiplerin tuzlu koşullarda yetiştiriciliğinde tuzluluk stresin tohum çimlenmesine ve fide gelişimine olan etkilerini tolere edebileceğini ve tuzluğunun bitki verimini çok etkilemeden siyah havuç köklerinde antiyosiyanin içeriğini artırmada olumlu bir etki yapabileceğini göstermektedir.Abiotic stress factors, especially salinity, significantly impact seed germination, seedling growth, and overall plant development. This study focused on evaluating salinity tolerance in two native black carrot genotypes (Eregli and Hatay Siyahı) and one commercial orange carrot genotype (Dragon) during the germination stage. Seeds were exposed to different concentrations NaCl (50, 100, 150, and 200 mM). Key parameters measured included germination rate, plumule and radicle length, ion leakage, and leaf pigment content. Salinity stress caused a noticeable decline in germination percentage, seedling length, germination speed, and seed vigor index across all genotypes. However, the black carrot genotypes showed better tolerance to high salinity levels compared to the orange genotype. At 200 mM NaCl, germination was severely inhibited in all genotypes. Interestingly, increasing salinity levels led to higher concentrations of chlorophyll b, carotenoids, anthocyanins, and lycopene in all genotypes. The black carrots, known for their high anthocyanin content, showed a greater increase in anthocyanin and lycopene levels under stress. They also maintained higher germination rates and exhibited less ion leakage than the orange genotype. These findings suggest that black carrot genotypes, due to their rich anthocyanin content, are more resilient to salinity stress during germination. Moreover, salinity may even enhance the nutritional quality of black carrots by increasing pigment levels without significantly affecting yield
Electrochemical detection of foodborne<i> escherichia</i><i> coli</i> using carbon nanotube-incorporated pencil-drawn paper-based disposable biosensors
No full textBackground: In this study, electrochemical flexible paper-based biosensors were developed for rapid and sensitive detection of Escherichia coli, a pathogen and a significant concern in both public health and the food industry. The electrodes were fabricated by a simple pencil drawing method utilizing a commercial, cost-effective cutting tool. Using automated cutting tool to form the conductive graphite patterns enabled the fabrication of pencil-drawn paper-based electrodes with a high reproducibility. The polyclonal E. coli antibody-hybridized multi-walled carbon nanotubes (MWCNTs) were immobilized onto the working electrode surface to construct the biosensors. Results: The performance of the biosensors against E. coli was evaluated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. To the immobilization and performance conditions optimization results, the developed sensor demonstrated the best results at 7.2 pH, 10 mu g mL- 1 Ab-MWCNT conjugate loadings and 30-min incubation time. The pencil-drawn flexible paper-based biosensors showed a linear range of 10 degrees-107 CFU mL- 1 with a low limit of detection (LOD) of 2.6 x 101 CFU mL-1. The sensor exhibited high repeatability with a low Relative Standard Deviation (RSD) % of 2.8. The sensors demonstrated remarkable selectivity against various culture environments and good performance in detecting E. coli in apple juices as real samples. In addition, the developed biosensor successfully detected a wild-type E. coli strain which was isolated from a street food and genetically confirmed as E. coli in this study. Significance: Our results suggested that disposable paper-based pencil-drawn flexible electrodes can be used to develop low-cost biosensors with high sensitivity and selectivity against E. coli. To the best of our knowledge, it is the first report using the pencil-drawing method for electrode fabrication for detection of E. coli and its appli-cation in real samples
Improving primary school mathematics teachers’ use of children’s literature in mathematics instruction
No full textSon yıllarda çocuk edebiyatı ile matematik öğretiminin bütünleştirilmesi matematik eğitimcileri açısından farklı bir öğretim metodu olarak kullanılmaya başlanmıştır. Bu birlikteliğin verimli bir şekilde uygulanıp yürütülmesi öğretmenlerin bu konuda ne kadar donanımlı ve bilgili olduğu ile ilgili olabilir. Bu çalışmanın amacı da ilköğretim matematik öğretmenlerini çocuk edebiyatının matematik dersine entegre etmeleri açısından geliştirilmesine yönelik bir eğitim vererek çocuk edebiyatını matematik öğretiminde kullanmalarını sağlamaktır. Nitel bir çalışma olarak yürütülen araştırma durum çalışması deseni benimsenmiştir. Üç aşamada gerçekleştirilen araştırmanın ilk aşaması ilköğretim matematik öğretmenlerinin derslerinde çocuk edebiyatını kullanmaları konusunda ne tür ihtiyaçlarının olduğunu belirlemek ile başlamıştır. Bu amaçla 78 öğretmene görüşme formu doldurtulmuş, formlar analiz edilerek öğretmenlerin ihtiyaçları belirlenmiştir. Araştırmanın ikinci aşamasında 2024-2025 eğitim Öğretim Yılı’nın 2.döneminde, 9 tane öğretmene “Çocuk Edebiyatını Matematik Dersine Entegre Etme Eğitimi” verilmiştir. Son aşamada ise eğitim sonrasında öğretmenlerin eğitim hakkında görüşleri alınmış, gönüllü olan iki öğretmen ile kendi sınıflarında uygulamalar yapılmıştır. Uygulanan eğitim sonrası öğretmenler matematik içerikli kitapları tanımış, kitaplarla hazırlanan etkinliklerin uygulanma aşamasına aktif olarak katılmış, kitapları kullanarak nasıl ders tasarlayacaklarını ve hazırladıkları ders tasarımlarının nasıl uygulanacağını öğrenmişlerdir. Araştırmanın sonucunda ilköğretim matematik öğretmenlerinin aldıkları eğitimin onlarda farklı bir bakış açısı oluşturduğu, çocuk edebiyatı kullanarak çocukların derse karşı ilgi ve meraklarını harekete geçirebilecekleri, matematiğin hayatın içinden olduğunu gösterebilecekleri, dersi daha eğlenceli kılabilecekleri yönünde görüş bildirmişlerdir.In recent years, the integration of children’s literature into mathematics instruction has emerged as an alternative teaching method for mathematics educators. The effective implementation and continuation of this integration may depend on how well-equipped and knowledgeable the teachers are in this regard. The aim of this study is to provide training to improve primary school mathematics teachers’ ability to integrate children’s literature into mathematics lessons, thereby enabling them to use children’s literature in mathematics instruction. Conducted as a qualitative study, the research adopted a case study design. Implemented in three phases, the first phase began with identifying the needs of primary school mathematics teachers regarding the use of children’s literature in their lessons. For this purpose, interview forms were administered to 78 teachers, and the responses were analyzed to determine their needs. In the second phase, during the second semester of the 2024–2025 academic year, nine teachers participated in the “Integrating Children’s Literature into Mathematics Lessons” training program. In the final phase, teachers’ opinions about the training were gathered, and classroom implementations were carried out with two volunteer teachers in their own classes. Following the training, teachers became familiar with mathematics-related books, actively participated in the implementation of activities prepared using these books, and learned how to design lessons with the books as well as how to implement the lesson plans they had prepared. The findings of the study indicate that the training provided primary school mathematics teachers with a new perspective, enabling them to stimulate students’ interest and curiosity in the subject through the use of children’s literature, demonstrate the relevance of mathematics to everyday life, and make lessons more engaging and enjoyable
A novel de/vs hybrid algorithm for enhanced optimization in numerical and engineering problems
No full textEffectively balancing exploration and exploitation is crucial for metaheuristic algorithms to achieve high-quality solutions in complex search spaces. The proposed DE/VS hybrid algorithm combines the strengths of differential evolution (DE) and vortex search (VS) to enhance global optimization performance. DE provides robust exploration but struggles with exploitation, while VS excels in exploitation but lacks exploration, often leading to premature convergence. The DE/VS framework introduces a hierarchical subpopulation structure and dynamic population size adjustment, ensuring a balanced trade-off between exploration and exploitation. This adaptive mechanism enhances convergence efficiency and prevents stagnation. Experimental evaluations across benchmark functions and engineering problems confirm that DE/VS consistently outperforms traditional methods. Statistical analysis further validates its superiority, demonstrating its effectiveness in solving complex optimization problems
Baer and extending conditions on modules and bimodules
No full textIn this paper, we provide a framework which enables us to abstract and extend various Baer, quasi-Baer, Rickart, and p.q.-Baer conditions (i.e., Baer annihilator conditions) for modules. In particular, this framework allows us to generalize the theory of Baer annihilator conditions for right R\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}{\varvec{R}}\end{document}-modules of T.K. Lee and Y. Zhou and the theory of Baer annihilator conditions for (H,R)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}(\textbf{H}, {\varvec{R}})\end{document}-bimodules of G. Lee, S.T. Rizvi, and C.S. Roman where H=End(MR)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}\textbf{H}= {\varvec{End}}({\varvec{M}}_{\varvec{R}})\end{document} and M is a right R\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}\varvec{R}\end{document}-module. To encompass the theory of Baer annihilator conditions for (H,R)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}(\textbf{H}, \varvec{R})\end{document}-bimodules of Lee, Rizvi, and Roman, we consider Baer annihilator conditions for (S,R)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}{\varvec{(S, R)}}\end{document}-bimodules where S\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}\varvec{S}\end{document} may not be H\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}\end{document}. One of the major pioneering results of the (H,R)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}(\textbf{H}, {\varvec{R}})\end{document}-bimodule theory by Rizvi and Roman was to obtain a module analogue of the Chatters-Khuri Theorem which links the Baer condition and the extending condition for rings.Our theory generalizes the Rizvi-Roman result to (S,R)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}{\varvec{(S, R)}}\end{document}-bimodules where S\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}{\varvec{S}}\end{document} is not restricted to being H\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}\end{document}. Among other results, we investigate conditions on S\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}{\varvec{S}}\end{document} or a left S\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}{\varvec{S}}\end{document}-module, M\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}{\varvec{M}}\end{document}, such that either one or both satisfy a Baer annihilator condition. Examples are provided to illustrate and delimit our results
Aging together: A sustainability assessment framework for double-aging neighborhoods-Kükürtlü district
No full textUrban neighborhoods experiencing socio-spatial pressures increasingly struggle with sustainability, especially in contexts where top-down redevelopment models dominate. In Turkey, the commonly used "demolish-and-rebuild" approach is often criticized for neglecting urban identity and the continuity of local communities. This study examines the K & uuml;k & uuml;rtl & uuml; Neighborhood in Bursa, a "double-aged" area characterized by both an elderly population and aging housing stock. Using a mixed-method approach, the study integrates the EcoDistricts framework with participatory spatial analysis and Interpretative Phenomenological Analysis (IPA) to assess sustainability across three priority areas: place, health and wellbeing, and connectivity. Results reveal that while the neighborhood faces structural limitations and underutilized public spaces, it benefits from strong social sustainability rooted in cultural continuity and intergenerational bonds, especially among long-term residents. Conversely, newcomers demonstrate weaker place attachment. These findings inform a set of inclusive, aging-in-place strategies aimed at balancing physical renewal with community preservation. Building on these insights, the study proposes a context-sensitive and potentially adaptable framework to guide sustainability efforts in similar aging urban contexts. The research contributes to international discussions on urban transformation by emphasizing the importance of integrating local lived experiences with spatial planning tools, offering a model for navigating demographic and physical aging in mid-sized cities
İngilizce öğretiminde küresel farkındalık: Sürdürülebilir kalkınma amaçları bağlamında bir karşılaştırma
No full textThis study investigates how Sustainable Development Goals (SDGs) are integrated into two English language coursebooks used in Turkey: A Ministry of National Education (MoNE)approved 9th-grade book and a commercially published A1+ book. Using comparative qualitative content analysis, the research examines both the presence and pedagogical depth of SDG-related themes. Guided by the 17 SDGs and their themes, a structured coding framework was applied to identify patterns and assess the thematic integration within each coursebook. Findings show that while both books include SDG content, the commercial coursebook demonstrates a broader and more balanced engagement, addressing a wider range of goals such as climate action, gender equality, and reduced inequalities across diverse activities. In contrast, the MoNE-approved book focuses heavily on SDG 4.7, limiting thematic diversity and interdisciplinary learning. These differences suggest that commercial materials may offer greater potential for promoting global citizenship and sustainability in English Language Teaching (ELT). The study highlights the need for curriculum developers, publishers, and educators to integrate sustainability themes more meaningfully into ELT materials. Although limited to two coursebooks and lacking classroom-level analysis, the research provides useful insights for enhancing global education through language teaching. Future studies are encouraged to expand the sample, include classroom perspectives, and explore ideological framing through discourse analysis.Bu çalışma, Türkiye'de kullanılan iki İngilizce ders kitabında Sürdürülebilir Kalkınma Amaçlarının (SKA'lar) nasıl entegre edildiğini incelemektedir: Millî Eğitim Bakanlığı (MEB) onaylı 9. sınıf ders kitabı ve ticari olarak yayımlanmış A1+ düzeyindeki bir ders kitabı. Karşılaştırmalı nitel içerik analizi yöntemiyle, her iki materyalde SKA temalarının varlığı ve pedagojik derinliği araştırılmıştır. Çalışma, Birleşmiş Milletler'in tanımladığı 17 SKA ve bunlara ilişkin temalar doğrultusunda yapılandırılmış bir kodlama çerçevesi kullanılarak metinlerdeki örüntüleri belirlemeyi ve tematik entegrasyonu değerlendirmeyi amaçlamıştır. Bulgular, her iki kitapta da SKA içeriği yer alsa da ticari kitabın iklim eylemi, toplumsal cinsiyet eşitliği ve eşitsizliklerin azaltılması gibi daha geniş bir yelpazedeki hedefleri çeşitli etkinlik türleriyle ele alarak daha dengeli ve kapsamlı bir yaklaşım sergilediğini ortaya koymaktadır. Buna karşılık, MEB onaylı kitap ağırlıklı olarak SKA 4.7’ye (Sürdürülebilir Kalkınma için Eğitim) odaklanmakta, bu da tematik çeşitliliği ve disiplinler arası öğrenmeyi sınırlamaktadır. Bu farklılıklar, ticari materyallerin küresel vatandaşlık ve sürdürülebilirlik eğitimine katkı sağlama potansiyelinin daha yüksek olduğunu göstermektedir. Çalışma, müfredat geliştiriciler, yayınevleri ve eğitimciler için SKA temalarının İngilizce öğretim materyallerine daha anlamlı şekilde entegre edilmesinin önemine dikkat çekmektedir. Sadece iki ders kitabının incelenmiş olması ve sınıf içi uygulamalara yer verilmemesi bu araştırmanın sınırlılıkları arasında yer almaktadır. Gelecek çalışmaların örneklemi genişletmesi, öğretmen ve öğrenci bakış açılarını içermesi ve söylem analizine dayalı ideolojik çözümlemeler yapması önerilmektedir