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A novel cloud point extraction method using a benzimidazole-based ligand for the preconcentration of toxic heavy metals in water and food samples
No full textIn the present research, a novel cloud point extraction (CPE) method was developed for the separation and preconcentration of toxic Cu(ii), Ni(ii), Pb(ii), and Cd(ii) ions in environmental water and vegetable samples, prior to their determination by flame atomic absorption spectrometry (FAAS). The ligand 2-(2-(4-fluorobenzyl)-1H-benzo[d]imidazole-1-yl)acetohydrazide (FB-BIAH) was employed for the first time as an analytical complexing agent for the aforementioned metal ions, and Triton X-114 (TX-114) was preferred as the nonionic surfactant. Within the scope of optimizing CPE conditions, experimental parameters, such as pH, FB-BIAH and surfactant amounts, and incubation temperature and time, as well as centrifugation speed and duration, were systematically investigated. The optimal conditions for the simultaneous quantitative recovery of analyte ions were established as pH 7.0, an FB-BIAH amount of 2.5 mg, a TX-114 quantity of 25 mg, an incubation temperature of 60 °C, and an incubation time of 30 min. Under optimal conditions, the proposed method was successfully applied to river water and seawater, as well as different vegetable samples such as lettuce, parsley, and pepper. The results obtained demonstrated that the analyte ions could be reliably determined in complex matrices and that the method exhibited high analytical performance. Due to its simplicity, rapid applicability, environmentally friendly nature, and cost-effectiveness, the proposed CPE-FAAS method represents a promising approach for the routine analysis of toxic heavy metals in environmental water and food samples
Advances in photovoltaic/thermal assisted ground source heat pump: structural design, material selection, coupling integration, and control strategy optimization
No full textPhotovoltaic/thermal (PV/T) systems have emerged as a promising auxiliary energy source for ground-source heat pumps (GSHPs), effectively mitigating long-term ground thermal imbalance and reducing grid electricity dependence. Despite their significant potential, comprehensive reviews of hybrid PV/T-GSHP systems remain scarce in recent literature. This study addresses this gap through a systematic review of advancements reported in over 150 recent studies, with particular emphasis on system architecture, functional materials, multi-source coupling integration, and advanced control strategies. Key areas examined include optimized designs of ground heat exchangers and PV/T heat collection components, the incorporation of nanomaterials to enhance heat transfer and photovoltaic efficiency, hybrid configurations integrating air-source heat pumps, solar roadways, and biomass systems, as well as intelligent operational and energy management strategies. Recent progress demonstrates that synergistic optimizations in structure, materials, and energy coupling can achieve up to 20 % improvement in overall exergy efficiency, a 25.6 % reduction in PV panel peak temperature, and a heating coefficient of performance (COP) reaching 6.0. These findings provide critical insights into performance enhancement pathways for PV/T-GSHP systems, offering substantial implications for improving building energy efficiency and accelerating the realization of carbon peak and neutrality targets in the building sector
More than just awareness: Longitudinal evaluation of an eating disorders training program for school counselors
No full textBackground: Eating disorders (EDs) are complex psychiatric conditions that often remain undetected in school settings. School counselors (SCs), as frontline observers, may play an important role in early recognition and referral. This study evaluated the effectiveness of a training program designed to support SCs' knowledge, attitudes, and practices regarding EDs in Türkiye. Methods: Data were obtained from forty-nine SCs from Erzincan, Türkiye, who had previously provided baseline data (T0) and participated in a longitudinal study with two additional assessment time points: post-training (T1) and three-month follow-up (T2). The training consisted of a full-day, primarily didactic seminar incorporating clinical vignettes. Participants' recognition knowledge, referral preferences, attitudes, and stigma levels were assessed using a structured, study-specific questionnaire. Results: The training led to a short-term increase in preference for hospital-based referral (T0: 61%, T1: 83%, p = .005), but this effect diminished at follow-up (T2: 67%). Knowledge about anorexia nervosa also improved post-training but declined significantly by T2. No significant changes were observed in correct diagnostic recognition, referral to a psychiatrist, or most attitudinal measures. Total stigma scores increased immediately after training (T0: 30.7, T1: 34.1, p < .001), partially decreasing at follow-up. Conclusion: A didactic, vignette-based training program was associated with temporary changes in selected knowledge domains and referral preferences, but these effects were not sustained. The absence of improvement in diagnostic recognition and the short-term increase in stigma highlight the limitations of brief, information-focused approaches. Future studies may explore whether more interactive, empathy-focused, and repeated training formats are associated with more durable and balanced outcomes
Honey as a bioindicator of microplastic pollution: insights from industrial and special honey types
No full textMicroplastics (MPs) are emerging contaminants increasingly detected in food products, raising concerns about human exposure and potential health risks. Honey is a relevant matrix due to its nutritional value, widespread consumption, and close links to environmental quality through bee foraging and processing practices. This study presents a paired comparison of industrial and special (artisanal) honeys within a single country and integrates polymer-specific risk indicators with human exposure estimates in one analytical framework. Fifteen honey samples from T & uuml;rkiye, including eight industrial and seven special honeys, were analyzed using stereomicroscopy and Fourier Transform Infrared (FTIR) spectroscopy to determine MP abundance, morphology, and polymer composition. MPs were detected in 93% of samples, with significantly higher concentrations in special honey (11.4 MPs/sample) than in industrial honey (4.9 MPs/sample) (p < 0.05). Fragments dominated (67%) over fibers (33%), and particle sizes ranged from 85 to 1200 & micro;m. The most common polymers were ethylene-vinyl acetate, polyethylene terephthalate, polyethylene, halogen-free flame-retardant polymers, and polyamide. Estimated daily intake ranged from 0.16 to 0.38 MPs/day, equivalent to 4169-9699 MPs lifetime. Although honey is not a major dietary MP source, its consistent contamination highlights cumulative exposure pathways and supports its role as a bioindicator of environmental MP pollution
The relationship between collateral circulation and electrocardiographic frontal QRS-T angle in patients with coronary artery chronic total occlusion
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Open AccessArticle
The Relationship Between Collateral Circulation and Electrocardiographic Frontal QRS-T Angle in Patients with Coronary Artery Chronic Total Occlusion
by Muhammet Öztürk 1ORCID,Nadir Emlek 1ORCID,Ali Gökhan Özyıldız 1,*ORCID,Elif Ergül 1ORCID,Hüseyin Durak 1ORCID,Afag Özyıldız 2ORCID andMustafa Çetin 1ORCID
1
Department of Cardiology, Faculty of Medicine, Recep Tayyip Erdoğan University, Rize 53100, Turkey
2
Department of Cardiology, Training and Research Hospital, Recep Tayyip Erdoğan University, Rize 53100, Turkey
*
Author to whom correspondence should be addressed.
J. Clin. Med. 2026, 15(1), 148; https://doi.org/10.3390/jcm15010148
Submission received: 11 November 2025 / Revised: 7 December 2025 / Accepted: 15 December 2025 / Published: 24 December 2025
(This article belongs to the Section Cardiology)
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Abstract
Background: Ischemic heart disease is the primary contributor to global mortality. The QRS-T angle at the anterior aspect of the heart serves as a significant biomarker of the heterogeneity in myocardial repolarization and the electrophysiological instability of the cardiac myocytes. A wide frontal QRS-T angle is associated with proximal vascular disease, coexistence of three-vessel disease, and increased mortality. Hereby, we aimed to examine the relationship between collateral circulation and frontal QRS-T angle in patients with chronic total occlusion (CTO). Methods: A cohort comprising 120 patients (17 females, 14.1%) who received a diagnosis of chronic total occlusion (CTO) subsequent to the administration of coronary angiography conducted for the evaluation of stable angina pectoris was incorporated into the investigation. The electrocardiographs of the patients were evaluated in detail, and the frontal QRS-T angle was calculated. The patients were categorized into two groups: subjects exhibiting an increased frontal QRS-T angle (>110° for men, >90° for women) and those presenting with a normative frontal QRS-T angle. Coronary angiographies of the patients were analyzed, and coronary collateral circulation was classified according to Rentrop classification. Results: Serum albumin level (OR = 0.711, 95% CI 0.564–0.896; p = 0.004) and poor collateral flow (OR = 17.7, 95% CI 12.2–85.3; p < 0.001) were significant predictors of raised frontal QRS-T angle. Conclusions: The frontal QRS-T angle is a novel parameter that is more reliable, consistent, and less sensitive to miscalculation and misidentification than other conventional electrocardiographic myocardial repolarization parameters. Revealing the bad collateral relationship with the frontal QRS-T angle may enable physicians to take more stringent precautions and change the risk factors related to the increased QRS-T angle in advance
The collective mind: Exploring teachers' and parents' understanding of autism Spectrum disorder in an inclusive school setting
No full textThe global prevalence of autism is increasing across different races, ethnicities, and backgrounds. Despite this rise, cultural factors which influence many areas of life play a key role in shaping how autism is understood. These factors also affect the school experiences of individuals with autism. Therefore, exploring how autism is perceived in various cultural settings is important for gaining a global perspective on inclusive education. This case study investigates how teachers and parents in a collectivist society understand autism and how cultural values shape their views. The study was conducted at a school in T & uuml;rkiye, where collectivist culture is widely observed. A mixed-methods design was used: the qualitative part included 13 participants (nine teachers and four parents), while the quantitative part involved 51 participants (teachers and parents). Data were gathered using demographic forms, semi-structured interviews, and the Societal Attitudes Towards Autism Scale. Thematic analysis was applied to qualitative data, and SPSS was used for quantitative data. Findings showed limited understanding of autism among school stakeholders, largely influenced by cultural beliefs. While collectivist culture initially appeared supportive, it later posed barriers to inclusive education. These results highlight the need for culturally informed training programs to improve autism understanding
Habits in the boil: how electric kettles reveal barriers and opportunities for sustainable energy transitions
No full textHousehold energy practices significantly influence broader sustainability transitions, yet they often receive limited scholarly attention compared to large-scale systems. This paper critically examines the role of electric kettles as a lens into behavioural inertia, technological efficiency, and the psychological drivers shaping domestic energy use. Drawing on recent data from the UK and Türkiye, the study compares the efficiency, cost, and cultural factors influencing kettle versus stovetop boiling, demonstrating that despite their high thermal efficiency, electric kettles’ potential for energy savings is constrained by ingrained user habits. The paper explores how psychological, cultural, and practical barriers hinder optimal kettle use and outlines how innovative control technologies, design innovations, and behaviourally informed policy interventions could unlock significant cumulative savings. Findings underscore the importance of combining technical innovation with user-centred strategies to shift everyday practices, arguing that even small appliances play a pivotal role in achieving large-scale carbon reduction targets
Investigation of the super-lift Luo converter controlled with PI and SM control for electric vehicle battery sources
No full textThis study examines the efficacy of a super-lift Luo converter for electric vehicle (EV) battery applications, aiming to determine an appropriate control strategy under fluctuating voltage situations. The converter is controlled by two methods: sliding mode control (SMC) utilizing pulse width modulation (PWM), and the traditional proportional-integral (PI) controller. A comprehensive comparative analysis is conducted in MATLAB/Simulink by modeling the converter using both continuous DC and lithium-ion battery voltage sources. The simulation findings indicate that an input of 12 V produces 36.07 V with SMC and 36.27 V with the battery source, while SMC attains an efficiency of 91.25 %. In comparison to the PI controller, SMC demonstrates a more rapid settling time and enhanced dynamic response in variable voltage settings. This simulation-based work offers significant insights into the selection of control algorithms for modern DC-DC converters utilized in electric vehicle systems. The findings demonstrate that SMC-controlled super-lift Luo converters provide a reliable and effective solution for electric vehicle battery systems
Microplastic ingestion in invasive mosquitofish (Gambusia holbrooki): a nationwide survey from Türkiye
No full textMicroplastics are widespread pollutants in freshwater ecosystems, yet comprehensive data on their occurrence across large geographic scales remains scarce. This nationwide study, therefore, examined microplastic ingestion in 621 individuals of non-native Gambusia holbrooki across 24 freshwater sites in Türkiye, selected to represent diverse hydrological types and anthropogenic pressures. Microplastic particles were extracted from the gastrointestinal tracts and analyzed for morphology, polymer type, size, and color using stereomicroscopy and ATR-FTIR spectroscopy. Fibers were the dominant shape (66%), followed by fragments (23%), films (9%), and spheres (2%). The most common polymer types were polyethylene terephthalate (PET, 40%) and polyethylene (PE, 28%), while black (35%) and blue (22%) were the most frequent colors. Over 80% of particles measured less than 1 mm in size. Microplastic loads were higher in lentic systems and areas influenced by agricultural or domestic discharge, highlighting spatial variability driven by land use and waterbody type. This pattern aligns with the ecology of G. holbrooki, whose surface-feeding behavior and preference for lentic waters likely increase its exposure to microplastics. These findings demonstrate the utility of G. holbrooki as a bioindicator of localized microplastic pollution. Future monitoring programs should integrate land-use data and adopt multi-species approaches to capture the full spectrum of contamination. This study supports the inclusion of adaptable, invasive species in cost-effective freshwater pollution assessments and informs targeted management strategies
Effect of saliva contamination and decontamination procedures on bond strength to framework materials
No full textBackground: The proper and reliable functioning of the bonding mechanism in the presence of saliva is a challenging process. The aim of this study was to evaluate the effect of decontamination methods on surface roughness, contact angle, and shear bond strength of various framework materials bonded to composite resin cement. Methods: A total of 180 specimens were prepared, with 60 specimens each from zirconia and two different production methods of CoCr alloys. The specimens were randomly separated to 6 subgroups for each material; no saliva contamination served as a control group. Group CO: saliva contamination, group AW: saliva contamination + air dried and water rinsed, group S: saliva contamination + air abrasion, group K and group Z were treated with different cleaning solutions after saliva contamination. Prior to resin cement application, zirconia primer was applied to the zirconia specimens, while alloy primer was used for the CoCr alloys specimens. Shear bond strength test was measured with universal test machine (3340, Instron Corp., Wycombe, UK). Fracture analysis was evaluated with stereomicroscope. Water contact angle was measured using a goniometer, and surface roughness was assessed with a profilometer. Statistical analysis was conducted using ANCOVA and multiple comparison tests at a 0.05 significance level. Results: All decontamination methods enhanced SBS values compared to the saliva-contaminated groups. However, only sandblasting (Group S) revealed significantly higher SBS values than the other decontamination methods for all frameworks (p < 0.05). Decontamination methods altered the surface roughness and contact angle values of all framework materials. Conclusions: Decontamination process after saliva contamination enhanced the bond strength and wettability. Cleaning solution may be the alternative decontamination technique to sandblasting for framework materials