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Bi-Hamiltonian structure in Fermi coordinates
No full textWe show that every smooth autonomous dynamical system determined by a never vanishing vector field on a three dimensional manifold locally admits a bi-Hamiltonian structure such that Fermi coordinates in the normal bundle of an integral curve correspond to Hamiltonian functions
Microbial Decontamination of Fresh-Cut Carrots via Cold Atmospheric Plasma Treatment: Effect on Physicochemical and Nutritional Properties During Storage
No full textThe extension of shelf-life and enhancement of the safety and quality of fresh-cut ready-to-eat vegetables is an ongoing public health concern. The present study investigated the efficacy of cold atmospheric plasma (CAP) treatment for the decontamination of fresh-cut carrots inoculated with Escherichia coli. An atmospheric plasma jet system operating at 1 kVA was utilized for treatment with varying plasma jet nozzle to sample distances (10-40 mm), exposure times (10-60 s) and either argon or dry air at 3 bar as working gases. It was demonstrated that both working gases achieved more than 4 log reductions in E. coli within 60 s of treatment while maintaining carrot surface temperatures below 50 degrees C. During 3-week storage at 4 degrees C, the immediate effects of plasma treatment on quality parameters were found to be minimal, with no significant changes observed in color (Delta E < 3.0) parameters, beta-carotene content, ascorbic acid levels, total phenolic content (TPC), or total antioxidant activity (TAA) following either treatment. Additionally, plasma-treated carrots retained their firmness, showing no significant texture loss, whereas untreated controls experienced a firmness decline of approximately 9% by the end of storage. Notably, TPC increased by up to 41%, and TAA increased significantly (p < 0.05) in plasma-treated samples during storage, especially in dry air plasma-treated carrots. These results demonstrated that CAP treatment can be successfully applied for rapid inactivation of E. coli on fresh-cut carrot surfaces while preserving original quality characteristics during refrigerated storage, offering potential as non-thermal preservation technology for fresh produce.Trakya University Office of Scientific Research Projects Coordinations, TUBAP; [2016/104]This research was funded by the Trakya University Office of Scientific Research Projects Coordinations, TUBAP, Grant No. 2016/104
Synthesis, Characterization, and Biological Evaluation of Quercetin-Boronate@Cu-hNFs and Quercetin-Boronate@Zn-hNFs: AChE Inhibition, Antioxidant, Anticancer, Antibacterial, Antibiofilm Activity Against Multidrug-Resistant Bacteria and Molecular Docking Studies
No full textIn this study, hybrid nanoflowers (hNFs) were synthesized using quercetin-boronate as the organic component and zinc (Zn-2(+)) and copper (Cu-2(+)) ions as the inorganic components. The obtained nanostructures were characterized using field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and elemental mapping techniques. To evaluate their bioactivities, antioxidant properties, acetylcholinesterase (AChE) enzyme inhibition, anticancer effects against the human lung adenocarcinoma (A549) cell line, and antibacterial activities were investigated against non-resistant strains of Staphylococcus aureus (S. aureus), Enterococcus faecalis (E. faecalis), Escherichia coli (E. coli), and Pseudomonas aeruginosa (P. aeruginosa), as well as drug-resistant methicillin-resistant S. aureus (MRSA) and multidrug-resistant E. coli (MDR E. coli). Additionally, antibiofilm activities were examined against MRSA and MDR E. coli strains. Molecular docking studies were performed to investigate the interactions of the quercetin-boronate ligand with target proteins including 1EVE, 4EY7, 2W9S, 1JIJ, 3U2D, 6P9Z, and 6QXS, in correlation with the observed bioactivities. Notably, Quercetin-Boronate@Zn-hNFs exhibited greater activity compared to Quercetin-Boronate@Cu-hNFs in 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2 '-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and AChE inhibition assays, with IC50 values of 15.6, 2.7, and 43 mu g/mL, respectively. The strongest antibacterial activity was exhibited by Quercetin-Boronate@Zn-hNFs against S. aureus and E. faecalis, with MIC values of 16 and 32 mu g/mL, respectively. In contrast, Quercetin-Boronate@Cu-hNFs demonstrated activity against MRSA and MDR E. coli strains with a MIC value of 256 mu g/mL. Furthermore, these hybrid nanoflowers exhibited dose-dependent antibiofilm activity. Docking scores for the quercetin-boronate ligand ranged from - 5.598 to - 9.152 kcal/mol, with the highest binding affinity observed against the 2W9S protein
Social media burnout and social anxiety as antecedents of discontinuous usage in the stressor-strain-outcome framework
No full textThis study aims to examine the structural relationships between problematic social media use (PSMU), social anxiety on social networking sites (SNSs), social media burnout (SMB), and discontinuous use from a stress-strain-outcome (SSO) framework. The research sample is 715 college students in T & uuml;rkiye (58.5% female, Mage: 21.71). Based on the SSO framework, PSMU and users' social anxiety on SNSs were identified as stressors. In response to these stressors, users' experience of SMB was determined as strain. As a result of this strain, users' discontinuous use of SNSs was identified as the outcome. Moderated mediation analyses revealed that SMB mediated the negative effect of PSMU on discontinuous use. The mediating effect of SMB was moderated by users' social anxiety on SNSs. Users' social anxiety on SNSs had a buffering moderating effect on the relationship between PSMU and discontinuous use. The moderating effect of users' social anxiety on SNSs was significant in the positive relationship between SMB and discontinuous use. SMB was positively correlated with both PSMU and discontinuous use. Similarly, self-evaluation anxiety and shared content anxiety were positively correlated with both PSMU and discontinuous use. These findings provide empirical evidence for the relatively new SMB paradox literature and extend the paradox of social anxiety phenomenon, which reveals contradictions in the face-to-face socialization process, to social media. The results demonstrate complex relationships between the antecedents of discontinuous use from the SSO framework.Scientific Research Coordination Unit of Anadolu University [SCB-2024-2493]This study was supported by the Scientific Research Coordination Unit of Anadolu University under the project number SCB-2024-2493
Reproductive biology of Centaurea kilaea (Asteraceae, Cardueae) – an endemic species from Türkiye
No full textIn this study, the embryology of Centaurea kilaea Boiss., a species endemic to Türkiye, was examined using light microscopy. The anthers of C. kilaea are tetrasporangiate; the anther wall development is dicotyledonous; and the tapetum is amoeboid. The meiotic division of the microspore mother cells is regular, and when the pollen grains are thrown from the anthers, they are three-celled. The ovary of C. kilaea is inferior, bicarpellary, syncarpous, and unilocular, which is characteristic of the Asteraceae family. It carries only a single ovule with basal placentation. The ovule is anatropous, unitegmic, and tenuinucellate. The megaspore mother cell undergoes meiotic division, giving rise to a linear tetrad of megaspores. The chalazal megaspore remains functional, and the other three megaspores degener-ate rapidly. The functional megaspore undergoes three mitotic divisions in succession. As a result, a Polygonum-type embryo sac, with eight nuclei and seven cells, is formed. The antipodal cells persist until the first divisions of the zy-gote. In the mature embryo sac stage, the integument consists of the endothelium, peri-endothelial region, parenchy-matous cells, and outer epidermis, from the inside out. Endosperm development is initially free nuclear, becoming cellular in the globular embryo stage. Embryo development is of the asterad type. The mature seed does not contain endosperm, but the endothelium persists. © 2025 Elsevier B.V., All rights reserved
Development of a practice guide and website for preparing classroom teacher candidates for inclusive education during teaching practice
No full textBu araştırmanın amacı, Sınıf Öğretmenliği Lisans Programı Öğretmenlik Uygulaması 1 ve 2 derslerinin, etkili kaynaştırma uygulamalarını destekleyecek şekilde yürütülmesinde öğretmen adayları ve uygulama öğretim elemanlarının kullanımına yönelik uygulama rehberi ve web sitesi geliştirmektir. Bu amaç doğrultusunda araştırmada tasarım tabanlı araştırma modeli kullanılmıştır. Araştırmanın katılımcı grubunu, Trakya Üniversitesi Eğitim Fakültesi Sınıf Eğitimi Anabilim Dalı'nda dördüncü sınıfta öğrenim gören yirmi sekiz öğretmen adayı oluşturmuştur. Araştırma sürecinde görüşmelerden elde edilen veriler, MAXQDA 24 veri analiz programı aracılığıyla betimsel analizle analiz edilmiştir. Araştırma sonucunda uygulama rehberinde, kaynaştırma eğitimiyle ilgili teorik içeriklerin; infografikler, uyarlanmış ders planı şablonu ve örnekleri, bilimsel yayınlar, öğretim etkinliklerinde yararlanılabilecek dijital kaynaklar, BEP'le ilgili güncel kaynaklar, öğretimsel uyarlamalara yönelik kontrol listeleri ve gözlem formları gibi materyallerle, uygulama okulunda gerçekleştirilebilecek uygulama temelli etkinlikler ve süreçte gerçekleştirilebilecek sosyal etkileşim toplantılarının öğretmen adayları tarafından olumlu geri bildirimlerle değerlendirildiği görülmüştür. Araştırmada öğretmen adaylarının çoğunluğu web sitesinin içeriğini yararlı bulmuş, KPSS hazırlık sürecinin yoğunluğu nedeniyle web sitesini genellikle bilgi alma ve bilgileri depolama amaçlı kullandıklarını, özellikle "özet", "videolar" ve "sesli sunular" gibi içeriklerden yararlandıklarını belirtmişlerdir. Öğretmen adayları bu süreçte uygulanan web destekli koçluk uygulamasına yönelik memnuniyetlerini ifade etmişlerdir. Ayrıca kaynaştırma öğrencilerine yönelik öğretimsel uyarlamaların ve BEP'nin gerekliliğini belirtmiş ancak uygulama okullarında bu uygulamalara yer verilmediğine yönelik gözlemlerini de paylaşmışlardır. Araştırmada, araştırma sonuçlarına dayalı olarak uygulamaya ve ileri araştırmalara ilişkin önerilere yer verilmiştir.The purpose of this research is to devel
ST Segment Elevation Myocardial Infarction as a Potentially Fatal Outcome of Variant Angina: A Case Report
No full text[Abtsract Not Available
Nanotechnological Approaches for Mitochondrial Targeting in Neurodegenerative Diseases
No full textObjectives Mitochondria are dynamic organelles essential for energy metabolism and cellular homeostasis, playing critical roles in ATP production, calcium regulation, redox balance, and apoptosis. However, mitochondrial dysfunction is a central factor in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease, amyotrophic lateral sclerosis, Huntington's disease, and Parkinson's disease. Given the essential role of mitochondria in neuronal survival, targeted therapeutic strategies that restore mitochondrial function have gained significant attention. This review explores the latest advances in mitochondrial-targeted therapies and their potential applications in neurodegenerative diseases. Methods A comprehensive literature review was conducted on mitochondrial-targeted therapeutic strategies, with a focus on nanotechnology-based drug delivery systems. The analysis includes various nanoparticle-based approaches, such as liposomes, DQAsomes, and polymeric nanoparticles, which have demonstrated high biocompatibility, controlled drug release, and enhanced mitochondrial targeting efficiency. Additionally, mitochondria-penetrating peptides and delocalized lipophilic cations (DLCs) are discussed for their role in improving drug localization within mitochondria and overcoming biological barriers, including the blood-brain barrier (BBB). Results Recent research shows the potential of mitochondrial-targeted antioxidants, peptides, and biocompatible nanocarriers in arranging mitochondrial dysfunction and protecting neurons from oxidative damage. Various nanoparticle-based drug delivery systems have demonstrated the ability to selectively target mitochondria, improving drug bioavailability, therapeutic efficacy, and neuroprotective outcomes in neurodegenerative diseases. Conclusion Mitochondria-targeted therapies provide promising avenues for disease-modifying treatments aimed at preserving neuronal integrity and delaying disease progression. The unique properties of nanoparticles, such as their ability to enhance drug stability, facilitate controlled release, and achieve precise mitochondrial localization, make them valuable tools for neurodegenerative disease therapy. Future research should focus on optimizing delivery systems, validating clinical applicability, and exploring interdisciplinary approaches to accelerate translation into effective treatments
Effects of a Digitally Supported Physical Activity Intervention in Knee Osteoarthritis: A Pilot Randomized Controlled Trial
No full textObjectives: The aim of this study was to investigate the effects of a digitally supported physical activity (PA) intervention on pain, physical function, exercise adherence and quality of life in females with knee osteoarthritis (OA). Methods: Thirty female participants with knee OA were randomly assigned to either a control group (n = 15) receiving patient education, smartwatch use, and a home exercise programme, or an intervention group (n = 15) receiving an additional digitally supported walking programme. The primary outcome measures were pain severity (Numerical Pain Rating Scale [NPRS]), physical function (Western Ontario and McMaster Universities Arthritis Index [WOMAC]) and exercise adherence. Secondary outcomes included quality of life (European Quality of Life Scale 5 Dimensions/EQ-5D-3L), daily step count and pain catastrophizing (Pain Catastrophizing Scale/PCS). Assessments were performed at baseline and after 8 weeks. Results: The intervention group showed significantly greater improvements in pain severity (1.4 cm larger improvement on NPRS; p = 0.005), physical function (6.4-point larger improvement on WOMAC total score; p = 0.003) and daily step count (1548 steps larger improvement; p = 0.045) compared to the control group. Both groups demonstrated similar significant improvements in exercise adherence, pain catastrophizing, and quality of life (p < 0.05). Conclusions: A digitally supported PA intervention, in addition to patient education and a home exercise programme, significantly improved pain, physical function and PA in females with knee OA. These findings support the efficacy of structured, supervised digital interventions for enhancing outcomes in this population. Future studies should explore strategies to enhance long-term adherence through digital PA interventions
Green Purification of Invertase from Ultrasonicated Sifted Baker's Yeast by Membrane Filtration: A Comparative Study
No full textThis study aimed to produce invertase with characteristics comparable to commercial formulations using a low-cost raw material, employing environmentally friendly extraction and refinement methods. Sifted yeast, the residual baker's yeast in industrial production, was used as raw material, and invertase in the yeast cell was extracted by ultrasonication and purified by micro- and ultra-filtration (MF and UF) methods. Subjecting the crude enzyme extract to MF followed by UF resulted in increased activity and specific activity. Through this process, the enzyme activity increased from 153 IU/mL to 691 IU/mL. The purified enzyme was lyophilized and the production of invertase at the laboratory scale was accomplished. The obtained enzyme was found to be stable at pH 5 and within the temperature range of 30-40 degrees C. It retained its activity for 60 days at -18 degrees C, whereas a 20% loss in activity was observed at +4 degrees C over the same period. As a result, it was demonstrated that invertase enzyme can be produced from a low-cost raw material which is considered as waste in the industry. To pass to the commercial production stage, processing of higher amounts of raw material by preventing foaming and heating problems in ultrasonication and scale-up studies testing the permeability properties of different membrane systems at a pilot-scale are necessary.Scientific and Technological Research Council of Turkiye (TUBITAK) [219O013]This research was funded by the Scientific and Technological Research Council of Turkiye (TUBITAK). Project number: 219O013