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Gestational diabetes mellitus and biomarker profiles: a bmi-stratified analysis of gremlin 1 and bmp 4—a cross-sectional study
No full textBackground/Objectives: We sought to examine serum concentrations of Gremlin 1 and BMP 4 in pregnant women diagnosed with gestational diabetes mellitus (GDM) compared to healthy pregnant controls while also exploring potential associations with body mass index (BMI) and gestational age. Methods: Our cohort comprised 72 pregnant women—35 with GDM and 37 healthy controls. We measured serum levels of Gremlin 1 and BMP 4 and stratified participants according to BMI categories. Statistical comparisons employed appropriate tests for group differences, and we used Spearman’s correlation to evaluate relationships among BMI, gestational age, fetal birth weight, HOMA-IR, Triglyceride-Glucose Index (TyG), QUICKI and biomarker levels. Results: BMI, triglyceride, HOMA-IR, and TyG were significantly higher, and QUICKI was lower in the GDM group compared with controls. Although Gremlin 1 levels were lower and BMP 4 levels and fetal birth weight were higher in the GDM group, these differences were not statistically significant. In BMI stratified analysis, both biomarkers were higher in the normal weight group, without significant differences. BMI correlated negatively with Gremlin 1 and BMP 4, and gestational age correlated negatively with both biomarkers. A strong positive correlation was observed between Gremlin 1 and BMP 4. Conclusions: The biomarker patterns observed in GDM appear distinct from those reported in diabetes mellitus, possibly reflecting pregnancy-related physiological weight gain and shifts in body composition. The strong positive relationship between Gremlin 1 and BMP 4 lends support to the notion of coordinated regulatory pathways, potentially indicating cellular resistance to BMP 4’s pro-adipogenic actions. Larger longitudinal investigations incorporating detailed body composition assessments will be essential to elucidate their roles in gestational metabolic adaptations and their potential utility for GDM risk stratification
Association of the triglyceride-glucose index with inflammatory markers and dysregulation of adipokines in patients with metabolic syndrome
No full textBackground Triglyceride-glucose (TyG) index has emerged as a reliable surrogate marker for insulin resistance and an early indicator of metabolic dysfunction. However, its association with inflammatory markers and adipokine dysregulation in patients with metabolic syndrome (MetS) remains poorly understood. This study aimed to investigate the association of the TyG index with inflammatory biomarkers and adipokine profiles in adults diagnosed with MetS. Methods This cross-sectional study included 190 adults (aged 20-50 years) with metabolic syndrome (MetS), recruited from primary healthcare centers in Iran. We collected anthropometric and biochemical data, and calculated the TyG index, classifying participants into quartiles based on their TyG values. Fasting serum glucose (FSG), insulin, and lipid profiles were measured. Insulin resistance was assessed using the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR). In addition, inflammatory markers including tumor necrosis factor alpha (TNF-alpha), Interleukin-6 (IL-6), and high-sensitivity C-reactive protein (hs-CRP) long with serum levels of adipokines including leptin, adiponectin, resistin, visfatin, vaspin, and omentin-1 were measured using standardized assays. Results Higher TyG quartiles were associated with increased levels of insulin, HOMA-IR, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c), TNF-alpha, leptin, and resistin, and decreased levels of adiponectin (all p < 0.05). There were no significant differences in high-density lipoprotein cholesterol (HDL-c), IL-6, hs-CRP, visfatin, vaspin, or omentin-1. These associations remained significant even after adjusting for age, sex, body mass index (BMI), smoking status, and physical activity. Conclusion Our findings suggest that the TyG index reflects not only insulin resistance and atherogenic dyslipidemia, but also low-grade inflammation and adipokine imbalance in patients with MetS. Due to its simplicity and cost-effectiveness, the TyG index could be a useful tool for early metabolic risk assessment and identifying adipose tissue dysfunction
Benthic marine litter in the Black Sea: Hydrodynamic drivers, depth-related accumulation, and implications for regional management
No full textThis study provides a comprehensive and standardized assessment of benthic marine litter along the Turkish Black Sea coast, based on 191 bottom trawl hauls conducted across three seasons and 69 stations following the standardized MEDITS/iBotS protocol. Sampling was performed along the southern Black Sea coast between İğneada and Hopa, covering five distinct depth strata ranging from 0 to 125 m. Marine litter was classified into eight main categories and twenty-six subcategories. To analyze the drivers of litter distribution, a Generalized Additive Model (GAM) was employed to examine the effects of latitude, longitude, depth, and seasonality. The mean benthic litter density was 639 ± 54 items/km², with plastics representing the dominant component (77 % of all items; 497 ± 52 items/km²). Spatial patterns revealed pronounced heterogeneity, with litter densities ranging from 7.97 to 6272.54 items/km² and eight accumulation hotspots exceeding 1000 items/km². Six of these hotspots occurred in the Eastern Black Sea, a pattern influenced by the Rim Current and coastal eddies. Depth played a critical role in structuring benthic litter distribution. Litter abundance exhibited a distinct peak at 50–75 m. A Generalized Additive Model (GAM) revealed significant non-linear effects of latitude, longitude, and depth on benthic litter abundance, while seasonality showed no significant influence. Overall, the findings demonstrate that the benthic environment of the Black Sea is substantially impacted by plastic-dominated litter. The study underscores the value of bottom-trawl–based monitoring for detecting seafloor litter and highlights the potential role of commercial trawl fleets in removing accumulated litter
Cryogenic coating technique for performance recovery in silicon solar cells
No full textIn this study, the performance recovery process was performed on a commercially available EM5063 model solar cell in two stages. First, the solar cell was irradiated with UV light at a wavelength of lambda = 360 nm for 1 h daily over 12 weeks to examine its impact on photovoltaic parameters. After each irradiation, I-V measurements were taken under dark and light conditions (100 mW cm-2) to determine the open circuit voltage (VOC), short circuit current (ISC), fill factor, and efficiency (eta). The donor density (Nd) and junction barrier potential (Vbi) were calculated from C-V measurements. The efficiency of the solar cell exposed to UV irradiation decreased by approximately 61.5%, from 1.42% to 0.55%. In the second stage, the irradiated solar cell was cooled at 200 K in a vacuum chamber at 10-6 Torr, and its surface was coated with equal-sized Ag clusters (10-12 nm). Optical measurements showed that the Ag-coated solar cell displayed surface plasmon resonance at similar to 530 nm. This resulted in a 71% increase in efficiency, from 0.55% to 0.94%. This marks the first time that low-performance solar cells have been recycled using a cryogenic coating method
Azabenzimidazole-piperazine compounds as anticancer agents: Synthesis, biological evaluation, and molecular docking studies
No full textThe cytotoxic activities of the newly synthesized azabenzimidazole–piperazine hybrid compounds were evaluated against three human cancer cell lines-HCT116 (colon), PC-3 (prostate), and MCF-7 (breast)-as well as the non-cancerous human embryonic kidney cell line HEK-293. Among all tested candidates, compounds 6d, 6k, and 6l demonstrated the most pronounced anticancer activities, exhibiting IC₅₀ values below 25 μM across all three cancer cell lines. Notably, compound 6l inhibited HCT116, PC-3, and MCF-7 cells with IC₅₀ values of 18.4 ± 0.7 μM, 15.2 ± 0.4 μM, and 14.4 ± 0.2 μM, respectively. Compound 6d showed even greater potency against MCF-7 cells (10.7 ± 0.6 μM) and exhibited comparable activity against HCT116 (14.0 ± 0.4 μM) and PC-3 (17.7 ± 1.5 μM) cells. Compound 6k also displayed significant cytotoxicity, with IC₅₀ values of 24.8 ± 1.6 μM for HCT116, 18.7 ± 0.8 μM for PC-3, and 20.2 ± 0.4 μM for MCF-7 cells. The integration of in silico molecular docking results with in vitro cytotoxicity data strongly suggests that the synthesized compounds-particularly 6d, 6k, and 6l-exert their anticancer effects through a multifaceted mechanism of action
Assessing the mariner's role and human reliability in the post-accident evidence collection process: The case of ship grounding using a BN–SLIM approach
No full textGrounding accidents pose a significant risk to the environment, global logistics, maritime vessels and seafarers. A substantial proportion of literature pertaining to maritime accidents is dedicated to groundings, however to the best of knowledge, there is an absence of research papers investigating the processes of post-accident evidence collection. To address this gap, the present paper aims to identify an optimal evidence collection process for grounding accidents to evaluate the potential shortcomings and analyse the human factors contributing to deficiencies in this critical work. The evidence collection process on board is primarily coordinated by the master and supported by the officers, this study conceptually represents the mariner's collective role and reliability in managing post-accident documentation tasks. A fuzzy Bayesian Network (BN) is employed to model an ideal evidence collection framework and identify factors that may lead to failure in this intricate process. Subsequently, the human error probability (HEP) was determined with respect to the substantial tasks inherent in evidence collection process, by means of the Success Likelihood Index Method (SLIM). In addition, the performance-shaping factors (PSFs) that initiate errors must were identified. The BN results indicate that the most effective causes of evidence collection failure were the collection of weather reports, ECDIS records and VDR data. The SLIM findings suggest that tasks with the highest error probability will be encountered during the collection of bridge records, and pinpoints the importance of stress, leadership and knowledge as the most influential factors affecting this task. The proposed framework and the outcomes of this study may contribute to post-accident response strategies of ship operators, masters and maritime insurance providers by demonstrating the importance of human reliability in complex post-accident situations
Heat transfer enhancement with low-concentration CuO/water nanofluid and ultrasonic energy: an experimental study
No full textThe use of heat transfer improvement methods is crucial for enhancing energy efficiency, minimizing system sizes, lowering costs, and promoting environmental sustainability. In this context, passive (fins, nanoparticles, etc.) and active (ultrasonic, magnetic field) heat transfer improvement methods are applied to the thermal systems. However, relatively few studies have examined the combination of nanofluid and ultrasonic enhancement. Taking advantage of this gap in the literature, this study presents the first systematic experimental investigation of a CuO/water nanofluid in laminar flow regime combined with low-power (Pus = 5 W) ultrasound (US), focusing on the synergistic effects on thermohydraulic performance. For this purpose, a heat flux of q″ = 2250 W·m−2 was applied to the surface of a smooth tube made of copper, and two different volumetric concentrations (φ = 0.01% and 0.05%) of CuO/water nanofluid were passed through it at four different Reynolds numbers (Re) of 500, 825, 1500, and 1780. In addition, US was applied at a frequency of f = 25.7 kHz at the entry section. The average Nusselt number (Nu) was found to increase with both the increase in Re and the application of US. With the application of US, the average Nu values of the systems containing water, φ = 0.01% and 0.05% CuO/water nanofluids were increased by 11.0 %, 2.0 %, and 4.0 %, respectively. However, when the nanofluid concentration was increased to φ = 0.05%, the average Nu decreased compared to φ = 0.01%, which was considered to be due to increased viscosity and particle agglomeration. The average friction coefficient (ff) increased with both nanofluid use and US. In experiments with water, an average of 20% increase was obtained with the US application, while increases of 15% and 10% were observed with φ = 0.01% and 0.05%, respectively. In measurements performed under NUS (non-ultrasonic) conditions, it was determined that φ = 0.01% and 0.05 % CuO/water nanofluids increased the friction in the system by 11.0% and 15.7 %, respectively. In terms of Performance Evaluation Criteria (PEC) analyses, the use of φ = 0.01% CuO/water nanofluid was more favorable than φ = 0.05%. Although PEC was higher in US conditions at low Re, NUS conditions were found to be more advantageous, as the average PEC values obtained under NUS conditions were 3.0% higher compared to US conditions. These findings demonstrate that the use of low-concentration nanofluid and optimal US application is critical to efficiency in heat transfer systems
From best tourism village to regional development: the power of destination image in an old Greek town Mustafapasa
No full textThis study examines the role of Perceived Value Theory and its potential for regional development in the context Mustafapasa, Turkey, which was selected as a Best Tourism Village (BTV) by UNWTO. Using a two-stage research design, the study first conducted a content analysis of 24 documents to identify the perceived image of Mustafapasa, followed by interviews with 13 participants to identify the key components of destination image. These components: history and culture, natural environment, social atmosphere and tourism activities were then compared with the sustainability goals of the BTV. The research highlights the partial achievement of these goals and emphasizes the need for greater local awareness and cooperation. The importance of this study lies in its contribution to Perceived Value Theory by demonstrating its application to rural tourism development. The findings suggest that increasing the perceived value of destinations such as Mustafapasa through strategic management can stimulate tourism, promote sustainable development and protect cultural and natural resources
A bibliometric analysis of alternative medicine practices: insights for wellness tourism and culinary health studies
No full textThis study aims to explore the scientific landscape of alternative medicine practices through bibliometric analysis and to interpret their relevance and potential contributions to wellness tourism and culinary health research. A bibliometric analysis was conducted on publications indexed in the Web of Science database from 1980 to 2024 using the search term “alternative medicine practices” in all fields. VOSviewer software was employed to analyse trends in publication volume, leading countries, institutions, authorship networks, and keyword occurrences. The analysis identified 13 thematic clusters, mainly focused on integrative medicine, mind-body therapies, oncology, and primary care. Particular attention was given to how the identified clusters and trends intersect with tourism and gastronomy. Indirect associations with tourism and gastronomy reflected in education, nutrition, and wellness-related terms were also detected, though their representation remains limited. The number of publications increased steadily from 1980 to 2021, with a notable surge during the COVID-19 pandemic, reflecting intensified interest in holistic health, preventive care, and dietary well-being. The findings indicate that alternative medicine practices research remains predominantly biomedical but shows emerging bridges with experiential domains such as wellness tourism and culinary health. These insights provide a basis for future interdisciplinary studies linking health, food, and tourism within integrative frameworks