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Gamma radiation synthesis of pH-sensitive CS/PVP/AMPS/AgNO3 grafted cotton gauze for biomedical applications
No full textIn this study, a new pH-sensitive chitosan (CS)/Polyvinyl Pyrrolidone (PVP)/2-acrylamido-2-methyl-propanesulfonic acid (AMPS)/AgNO3 grafted gauze was produced using gamma radiation polymerization. The swelling, swelling kinetics, and pH-sensitivity properties of the prepared CS/PVP/AMPS/AgNp-g-gauze were tested. The model drug preferred in this study was Methylene Blue (MB). FT-IR and SEM analysis have confirmed that CS/PVP/AMPS hydrogel composite-g-gauze was successfully synthesized. It was found that there was an increase in the grafting percentage with increasing AMPS monomer concentration in the formulation. Adding different concentrations of AgNO3 to the reaction medium caused no drastic change in the grafting percentage. Swelling kinetics from the new hydrogel composite-g-gauze was best fitted to both Peppas model and the second-order kinetic equation. Swelling, pH-sensitivity, and swelling kinetics of the hydrogel composite-g-gauze were improved with the addition of CS, PVP, and AMPS in the gel formulation
Modelling cybersecurity environment using Lotka-Volterra equations, and its stochastic analysis
No full textConventional cybersecurity models often analyse vulnerabilities, cyberattacks, and security measures in isolation, neglecting their dynamic interdependencies and feedback mechanisms. Such approaches fail to capture emergent behaviours, struggle to model evolving threats in complex environments, and lack a holistic perspective, limiting their practical applicability. To address these shortcomings, this study introduces an ecological modelling framework using extended Lotka-Volterra (LV) equations, conceptualising vulnerabilities, attacks, and security hardening efforts as a three-component cyber-ecosystem. The approach integrates deterministic modelling of core interactions-such as growth, mitigation, and feedback mechanisms-with stochastic methods, including Stochastic Differential Equation (SDE), Agent-Based Modelling (ABM), and Monte Carlo Simulation (MCS), to address real-world uncertainties. Lyapunov stability analysis is employed to evaluate system resilience under perturbations. The framework extends classical predator-prey dynamics by incorporating security hardening as a regulatory mechanism interacting with both vulnerabilities and attacks. Simulations examine stability regimes across parameter configurations, while phase-space trajectories are analysed to identify behavioural patterns influenced by stochastic factors. Analytical methods assess critical thresholds in vulnerability growth rates and security deployment efficiency that govern equilibrium conditions. By adapting ecological principles to cybersecurity, this work highlights the challenges of managing interdependent system components. The analysis explores how coordinated mitigation strategies influence stability, with integrated deterministic-stochastic modelling offering a systems perspective on resilience. The model's practical utility is exemplified through a hypothetical Smart Grid SCADA scenario, showcasing its ability to guide resource optimisation based on vulnerability and attack dynamics. This approach contributes a methodological framework for analysing cybersecurity ecosystems through quantitative stability metrics. It facilitates the evaluation of adaptive security architectures and resource allocation strategies, providing a robust bridge between theoretical modelling and practical cybersecurity challenges
Investigating the effects of phantom sensation on gait autocorrelation in transtibial amputees using signal processing techniques: A multidisciplinary analysis
No full textObjective: Phantom sensation (PS) is defined as the sensation of the amputated limb that persists after amputation. The aim of this study was to investigate the effects of PS on the autocorrelation feature of gait. The information obtained will contribute to the methods of analysis and intervention in the rehabilitation. Methods: Unilateral traumatic trans-tibial amputees with phantom sensation (PG) (n = 10) and with no phantom sensation (N-PG) (n = 11), and healthy controls (HC) (n = 11) were recruited. Individuals walked on the treadmill at their preferred speed while inertial motion units recorded 512 consecutive steps. Gait analysis was repeated with a 5 % perturbation on the treadmill. The following signal processing methods were utilized to investigate autocorrelation function of gait: multiscale entropy (MSE), detrended fluctuation analysis (DFA), rescaled range analysis (RRA), autocorrelation function (ACF), power spectral density (PSD), Lempel Ziv complexity (LZC), Higuchi fractal dimension (HFD), Katz fractal dimension (KFD), Renyi entropy (RE), and Tsallis entropy (TE). Results: PG (p = 0.049; d = 0.905) had better gait autocorrelation results than N-PG (p = 0.005; d = 1.234) on both regular and perturbed ground compared to the HC. PG showed more similar gait adaptations to healthy individuals. The LZC criterion and HFD yielded more significant results in differentiating between the groups in both ground changes and existing ground conditions (p = 0.05). Conclusion: The results demonstrated that phantom sensation is a functional sensation that enhances the autocorrelation function of gait and contributes to the neuromotor nature of gait. The proposed signal processing techniques may become an alternative option to the methods previously used in this field. © 2025 Elsevier B.V., All rights reserved
Where rivers meet the sea: Source fingerprinting and health risk mapping of potentially hazardous elements in sediments from the Çanakkale Strait basin (Türkiye)
No full textThis study presents a seasonal evaluation of potentially hazardous elements (PHEs) in surface sediments from eight riverine inputs to the Çanakkale Strait, Türkiye. The PHEs (Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, Cd, Ba, Pb) were analyzed across dry and wet seasons. Furthermore, this study introduces a novel integration of Monte Carlo Simulations (MCS) with ecotoxicological indices, offering a robust and probabilistic approach to risk assessment that moves beyond traditional deterministic methods. Multivariate analyses (PCA, Cluster Analysis) and Pearson correlations revealed distinct regional differences, with Biga Peninsula rivers exhibiting higher contamination, particularly in the dry season. Geoaccumulation and enrichment indices indicated moderate to significant enrichment of Cd, Pb, and Zn at specific sites. Composite ecological indices (e.g., TRI, RI) highlighted elevated risk at near the Karamenderes River mouth (ÇS4) and southwestern Biga Peninsula (ÇS8). In addition, MCS-based health risk modeling showed children face 8–10 times higher non-carcinogenic risk than adults, with Mn and Pb as key contributors. Arsenic and cadmium posed marginal carcinogenic risks, especially in children. These findings emphasize the combined influence of mining, agriculture, and domestic discharges, calling for targeted source control and regular monitoring in this geopolitically critical aquatic corridor. © 2025 Elsevier B.V., All rights reserved
Do serum endocannabinoid and N-acylethanolamine concentrations reflect their brain levels in two different rat stress models?
No full textBackgroundAlthough the brain is not the only source of circulating endocannabinoids and their levels can be affected by many factors, it is underlined that serum endocannabinoid levels can be used as a biomarker in psychiatric disorders. In this study, we aimed to examine whether serum endocannabinoid and N-acylethanolamine concentrations reflect their brain levels.MethodsIn the present study acute immobilisation (AIS) and post-traumatic stress (PTSD) models were applied to Wistar albino male rats. Rota rod performance, forced swim, open field and elevated plus maze tests were performed. Endocannabinoid and N-acylethanolamine levels in serum and hippocampus, amygdala and cortex were assessed using LC-MS/MS.ResultsWe observed significant increases in anandamide (AEA), palmitoylethanolamide (PEA) and oleoethylethanolamide (OEA) levels in the amygdala and hippocampus in both models except PEA in amygdala in the AIS group, while 2-AG levels decreased. There was no change in serum AEA and 2-AG levels in all groups; in the PTSD group serum PEA levels were higher whereas OEA levels were lower in both the AIS and the PTSD groups.ConclusionOur results show that there is no correlation in endocannabinoid and N-acylethanolamine levels between serum and specific brain regions in two stress models of rat.Trakya University Research Council [TUBAP-2023/78]This work was supported by a grant from Trakya University Research Council (TUBAP-2023/78)
Ecotoxicological Effects of MPs as Emerging Micropollutants: Examination of Biomarkers, Current State, and Future Perspectives
No full textKnown ubiquitously, including in terrestrial and aquatic ecosystems, microplastics (MPs) are pollutants of concern and their harmful effects pose a growing threat. MPs, especially when considered together with increasing pollution and destructions in the ecosystem, cause deterioration of ecosystem functions and structure, raising concerns about possible negative effects on the environment. The environmental effects of microplastics, which increase especially rapidly in different environmental conditions, have been still discussed by many researchers today. While studies generally focus on the increase and effects of MPS in the oceans and seas, there is still a knowledge gap regarding its status and effects in freshwater and soil. Therefore, it is very important to evaluate the effects of MPs on both terrestrial and aquatic ecosystems. The toxic compounds used as additives in the formation of microplastics absorb the pollutants in the environment during their stay in the land and aquatic environment and then may cause the development of microorganisms in these areas or threaten the environmental media by being directly assimilated by organisms. Therefore, this situation creates an ever-increasing danger and risk potential for ecosystems, and especially their sustainable presence on land and water creates negative effects on human health and the ecosystem. So, in this context, this book section aims to define MPs pollution in terrestrial and aquatic ecosystems and to determine the ecotoxicological effects observed in ecosystems. In addition to the presence and potential effects of microplastics in soil and clean waters, their effects on human-food security, animal, ecosystem, and human health will be focused on. At the same time, biomarkers of microplastics that cause oxidative stress and damage to microalgae will be investigated. In addition, it is also aimed to present the current challenges and perspectives for future research in the context of microplastics and their effects, which are also known as worrisome. © 2025 Elsevier B.V., All rights reserved
Our response to the letter to the editor for the article Comparison of survival between unilateral and bilateral breast cancers using propensity score matching: a retrospective single-center analysis
No full textThey expressed their concerns about making comments regarding the sample size in our study. The preferred propensity score analysis was the statistical method chosen because it is the analysis after balancing the small number of patients with the much larger number of patients in this situation in terms of both number and prognostic factors. In fact, the reference to future studies on this subject has been made for new retrospective series rather than prospective randomized studies. We wanted to draw the attention of researchers to propensity score analysis and to show that future retrospective series studies can ask questions with clearer answers using propensity score analysis
Globalization trends of local viticulture enterprises: The case of Thrace region
No full text20. yüzyılın sonlarına doğru hızla gelişmeye başlayan haberleşme ve bilgi teknolojileri, toplumlar arasında birçok etkileşimi beraberinde getirerek dünya üzerindeki mesafe kurallarını yok saymaktadır. Bu gelişmenin beraberinde doğduğu düşünülen küreselleşme kavramı, yerelleşme ve küyerelleşme kavramları ile doğrudan veya dolaylı olarak etkileşim sağlamaktadır. Ortaya çıkan bu homojenleşme ve hetorojenleşme döngüsünün tarım, haberleşme, ekonomi, sanat, siyaset ve insanoğlunun bulunduğu her alanda yer aldığı düşünülmektedir. Bağcılık ise insan hayatında tarih öncesi dönemlerden itibaren yer edinmiş köklü bir tarım dalıdır. Bu araştırma ise, küreselleşme kavramının bağcılık işletmeleri üzerinde dolaylı veya direkt olarak bıraktığı izlenimleri Trakya Bölgesi kapsamında ele almaktadır. Araştırma yöntemi olarak, literatür taraması, TÜİK, OIV, FAO, UNESCO ve işletmelerin sahip olduğu resmi web sitelerinden alınan ikincil verilerin kullanılması ve sektörde yer alan öncü isimler ile yüz yüze veya online görüşmeler sayesinde röportaj yapılması tercih edilmiştir. Sonuç olarak, Trakya Bölgesi'nin bin yılları aşan tarihi bağcılık mirası olduğu, sektördeki uzman kişi ve işletmelerin bölgeye yatırım yaptığı, bölgede bulunan işletmelerin sunduğu ürün ve hizmetler ile bölgenin sahip olduğu tarihi mirası dünya üzerinde duyurduğu, işletmelerin gerek yerel istihdam ve üretime katkı sağlayarak gerekse ihracat ve küresel organizasyonlarda adını duyurarak makro ve mikro ölçekte katma değer üretimi gerçekleştirdiği söylenebilmektedir.Towards the end of th
Seven ways to optimise prevention in general practice and family medicine - a EUROPREV position paper to spark debate on prevention
No full textPrevention is a fundamental aspect of the work of general practitioners (GPs) and family doctors (FDs); however, its implementation poses significant challenges due to conflicting guidelines, time constraints, competing demands, and equity concerns. This position paper proposes seven guiding principles to help GPs and FDs navigate preventive care effectively. It encourages GPs/FDs to recognise the intrinsic preventive value of high-quality general practice and adopt a critical approach to the evidence underpinning preventive recommendations. Prioritising a limited number of preventive services with a strong evidence base and targeting those patients most likely to benefit will contribute to sustainable, evidence-based, and equitable patient care
Comparative Accuracy Assessment of Orthophotos Produced Using Different UAV and Photogrammetric Software
No full text9th International Conference on Smart City Applications, SCA 2024 -- -- Tangier -- 331679Nowadays, the use of Unmanned Aerial Vehicles (UAVs) for producing maps of large areas is more advantageous in terms of both cost and time compared to Global Navigation Satellite Systems (GNSS). This study aims to produce orthophotos of a section of the Gebze Technical University Campus using aerial images obtained from two different UAVs and to compare their accuracy with GNSS measurements. A total of 77 points were established for georeferencing and accuracy control, measured in the TUREF/TM30 system using a GNSS device. Agisoft Metashape, Pix4D, and 3Dsurvey software were utilized to produce orthophotos of the study area. The positional accuracy of the orthophotos was assessed using checkpoints whose coordinates were determined by GNSS measurements. Agisoft Metashape achieved the best positional accuracy, while Pix4D software provided a smaller root mean square error on the Z-axis. The 3Dsurvey software had the longest processing time for the steps. The results obtained from studies conducted with all three software packages are within the acceptable limits defined by the Large Scale Map Information and Map Production Regulation. In conclusion, it has been determined that procedures typically performed by the GNSS/GPS can be effectively completed using UAVs, achieving high positional accuracy while saving time, reducing labor, and lowering costs. © 2025 Elsevier B.V., All rights reserved