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A comparative study of microplastic contamination and ecological risk in beach and bottom sediments along the southern Black Sea coast
No full textMicroplastics (MPs) are now recognized as widespread pollutants in marine ecosystems, with semi-enclosed seas such as the Black Sea particularly vulnerable due to restricted water exchange and extensive land-based inputs. This study presents the first comparative assessment of MP contamination and ecological risk between beach and bottom sediments along the entire Black Sea coast of Türkiye, which comprises the basin’s longest national shoreline. A survey was conducted at 64 sites (38 beaches and 26 bottom-sediment sites). Mean concentrations were broadly comparable across matrices, averaging 140.39 ± 10.38 MP/kg in beach sediments and 106.19 ± 8.74 MP/kg in bottom sediments, though site-specific hotspots exceeded 200 MP/kg for both matrices. Fibers were the dominant morphology in both matrices, with a significantly higher proportion on beaches (74.1 %) than in bottom sediments (53.5 %), while fragments and films were relatively more abundant in bottom sediments. Blue and black particles were common in both environments. Polymer analysis revealed a strong dominance of polyethylene terephthalate (PET) in beach sediments (59.1 %). In contrast, seabed sediments displayed greater heterogeneity, with substantial polymer types of polyethylene (PE), polypropylene (PP), polyamide (PA), and polyacrylonitrile (PAN). Multivariate analyses confirmed statistically significant compositional differences between matrices, with PET identified as the primary driver of dissimilarity. The Polymer Hazard Index (PHI) indicated severe ecological risks, with over 70 % of sites in both matrices classified in the highest hazard category (Class V), underscoring the persistence of hazardous polymers and their potential bioavailability
Smart structural design for vibration control and energy harvesting in sandwich structures with concrete cores and piezoelectric face sheets
No full textThis research examines the performance optimization of smart energy systems for vibration control and energy harvesting in coal mining components, with a focus on appropriate rock mechanics and dynamic interactions. External mechanical loads are applied to a sandwich plate model with a concrete core and sensor-actuator integrated face sheets to simulate structural elements used in mining applications. The structural formulation applies higher-order shear deformation theory (HSDT) to accurately account for the effects of transverse shear in thick composite laminates. The governing equations of motion are produced from Hamilton's principle, allowing an energy-based formulation to stay consistent with the foundation of the physics involved. Additionally, the generalized differential quadrature (GDQ) method is used for the spatial discretization in addressing the coupled electromechanical response, while the temporal domain is treated analytically with the Laplace transform. Various control strategies are verified (classical, robust, optimal) for their potential to suppress vibrations, while at the same time maximizing energy harvested. The comparative analysis developed was able to identify the most suitable controller to increase the stability of a concrete structure while also increasing the energy conversion efficiency, despite being acted on by both operational and non-operational disturbances. The framework proposed has great potential to enhance the reliability, durability, and self-sustainability of concrete structures. The results and findings of this thesis offer professional implications for understanding how to implement smart materials in combination with modern control algorithms and effective modeling practices for use in the practice of concrete engineering
Assessment of the burden of care in palliative care patients with invasive procedures from the perspective of the caregivers: a cross-sectional study
No full textBackground: A palliative care unit is a place where intensive treatment and care are provided for both patients and caregivers. In addition, some invasive interventions are needed to reduce the symptoms seen in end-stage patients. Aim: In this study, the relationship between the care burden experienced by caregivers of patients hospitalised in a palliative care unit and invasive procedures (intravenous applications were excluded from invasive procedures because they are routinely applied to all patients) was evaluated. Study Design: This cross-sectional study was conducted in Turkey. The following tools were used to collect data: the ‘Caregiver Information Form’, ‘Palliative Performance Scale (PPS)’ and the ‘Zarit Care Burden Scale’. Results: Although data were collected from 123 patients, informal caregivers and those who declined to answer certain questions were excluded from the final sample, ensuring that the target sample size was met. The final sample consisted of 107 caregivers. Results showed that the median care burden score was significantly higher among caregivers with low income (49 (14-72); p = 0.034), those caring for patients diagnosed with cerebrovascular events (58.5(19-70); p = 0.029), and those who underwent invasive interventions for various reasons (34 (10-73); p = 0.006). Additionally, 68.2% (n = 73) of caregivers reported feelings of distress for their patients and 57% (n = 61) experienced insomnia while providing care. The mean PPS score of the patients was 32.0 ± 20.0, and the median score of the Zarit Burden of Care Scale was 30 (10–73). The combined variables of caregiver age, days spent with the patient, and PPS score accounted for 17% of the variance in the Care Burden Scale (R = 0.444, R2 = 0.174, p < 0.05). Conclusions: Based on these findings, it is recommended that caregivers of patients receiving invasive interventions and those with low PPS scores receive both physiological and psychological support. Relevance to Clinical Practice: These findings highlight the need for targeted physiological and psychological support for caregivers of palliative care patients undergoing invasive interventions to reduce care burden and improve overall care quality
Advanced Techniques in Pattern Mining- continue
No full textData Mining 8. Hafta Ders Notu Konusu : Advanced Techniques in Pattern Mining- continu
New 1,3-benzoxazol-2(3h)-one aroylhydrazone and acetamide hybrids as promising acetylcholinesterase inhibitors: microwave synthesis, structure–activity relationship, and drug-likeness evaluation
No full textAbstract: Objective: A new series of benzoxazole-based aroylhydrazone and acetamide hybrids was designed, synthesized, and evaluated for acetylcholinesterase (AChE) inhibitory activity. In addition, a structure–activity relationship (SAR) study was performed, and absorption, distribution, metabolism, and excretion (ADME) properties were calculated using the SwissADME web tool. Methods: The synthesis of the hybrids was carried out using conventional techniques, a household microwave oven, and a monomode microwave reactor. Results and Discussion: The outcomes of the different synthetic approaches were compared. Most of the synthesized hybrids exhibited high inhibitory activity, with IC50 values ranging from 12.00 ± 0.15 to 18.50 ± 0.25 µg/mL, exceeding that of the reference drug galantamine (20.75 ± 0.25 µg/mL). SAR analysis revealed that the introduction of the aroylhydrazone moiety into the benzoxazole scaffold enhanced AChE inhibitory activity. In particular, the presence of chlorine-containing substituents on the benzoxazole ring positively influenced the activity. Conclusions: Furthermore, ADMET profiling indicated that all active compounds exhibited drug-likeness and complied with ADME rules, with no violations detected. Collectively, the newly synthesized hybrid compounds represent promising lead scaffolds for the treatment of Alzheimer’s disease
The relationship between gene subtypes, symptoms, and cardiac function in patients with familial mediterranean fever
No full textBackground/Objectives: Familial Mediterranean fever (FMF) is a chronic autoinflammatory disorder that can affect cardiac structure and function. However, the impact of different Mediterranean fever (MEFV) gene subtypes on clinical features and subclinical cardiac changes remains unclear. This study aimed to evaluate the association between MEFV gene subtypes, clinical features, and cardiac function in patients with FMF. Methods: A total of 98 patients with FMF were prospectively included. Twelve mutations in the MEFV gene were screened, and the M694V homozygous (Gene-1), M694V heterozygous (Gene-2), and M680I heterozygous (Gene-3) subtypes were analyzed. All patients underwent transthoracic echocardiography and speckle-tracking strain analysis. Results: The age of disease onset was earlier in patients carrying the gene-1 mutation compared to mutation-negative patients (11.4 ± 8.0 and 17.6 ± 11.4 years, respectively; p = 0.025). Disease duration was longer in patients with gene-1 mutation (23.3 ± 12.8 and 12.5 ± 9.3 years, respectively; p < 0.001), and disease activity score was higher (6.41 ± 1.9 and 5.15 ± 1.6, respectively; p = 0.007). Furthermore, left atrial contractile strain was significantly lower in this group (−10.6 ± 3.5% and −14.5 ± 6.1%, respectively; p = 0.012). Arthralgia was more frequent in patients with gene-2 mutation (p = 0.026), while left atrial contractile strain was better preserved compared to mutation-negative patients (p = 0.002). No significant association was found between gene-3 mutation and clinical or cardiac parameters. Conclusions: MEFV gene subtypes have different effects on clinical phenotype and cardiac function in FMF. These findings support the importance of genotype-based cardiac monitoring and risk stratification in FMF patients
Effects of different brewing conditions on acrylamide levels in Turkish green tea and assessment of carcinogenic and non-carcinogenic health risks
No full textIn this study, the effect of various brewing methods on acrylamide levels was examined using three different commercial green tea samples. The acrylamide exposure levels of 402 adult women living in different cities in Türkiye were assessed in terms of carcinogenic and non-carcinogenic health risks based on their green tea consumption data. A total of 81 brewings were performed in chrome-steel, French press, and porcelain teapots at water temperatures of 80, 90, and 95 °C and brewing times of 3, 5, and 7 min. The acrylamide level in the brewed teas ranged from 19.9 to 54.9 µg/L, and the average acrylamide level of all samples was determined to be 34.7 ± 3.95 µg/L. The study found that acrylamide levels were higher in green teas brewed at high temperatures for short periods. The EDI, THQ, CR, and MOEn/c values calculated using individual-based consumption data revealed that green tea does not pose a serious risk in terms of both carcinogenic and non-carcinogenic risks, as consumption levels are generally low. It should not be overlooked that green tea may contribute to a certain extent to total dietary acrylamide exposure, and exposure levels, particularly those related to consumption frequency and brewing habits, should be monitored regularly
New generation scour control using nano Xanthan-clay composite for bed protection
No full textLocal scour is a major cause of instability and structural degradation in hydraulic systems, driven by high-energy flows and sediment entrainment. Developing sustainable countermeasures remains an essential task in hydraulic engineering. This study investigates the effectiveness of xanthan gum in mitigating scour downstream of a rostral drop. The experiments were conducted in a fully turbulent flow regime (48,686 < Re < 110,160) with discharges between 5 and 8.33 L/s. The mobile-bed section was 1.0 m long with a 12-cm sediment layer in a 5-m-long, 0.33-m-wide rectangular flume. A drop structure with a 120° vertex angle and 15-cm height was installed 1.0 m upstream of the bed. Four xanthan concentrations (0.05%, 0.1%, 0.3%, 0.5% by weight) were tested together with a constant 10% clay content. A total of 160 experiments were categorized into four scenarios. The results indicated that clay alone provided moderate reductions in scour dimensions, while increasing xanthan concentrations produced progressively stronger improvements. The combined xanthan–clay mixture yielded the most significant enhancement, reducing maximum scour depth by more than 93%, demonstrating its strong potential as an eco-friendly scour-mitigation treatment. These scenarios were designed to isolate the role of natural clay in improving baseline cohesion and to assess how increasing xanthan dosage enhances mechanical resistance. This structure enabled a systematic evaluation of how progressive sediment modification influences downstream scour development
Reproductive pattern and length at first sexual maturity of the whiting (merlangius merlangus, nordmann, 1840) in the Black Sea
No full textSamples of whiting (M. merlangus) (n = 1545) were collected using bottom trawl in the southern Black Sea during 2017–2018 and were subjected to reproductive biology assessments. These assessments included the gonadosomatic index, macroscopic and microscopic gonad phases, oocyte diameter distributions, batch fecundity, microscopic analysis of oocytes, and histology. The assessment results revealed a significant difference in sex ratio the samples (female: 877, male: 668). Analyses of the gonadosomatic index (GSI), along with macroscopic and microscopic phase evaluations, indicated that the most intense reproductive periods occurred in May and November, with two peaks observed during the studied year. Examination of oocyte structures and diameter distributions in histological sections taken from the ovaries each month showed that the whiting in the southern Black Sea exhibited multi-spawning behavior and had determinate fecundity. Additionally, the monthly batch fecundity (FB) and relative batch fecundity (FBR) of spawning whiting were calculated throughout the year. The average FB was 17823 ± 21,353 hydrated oocytes, while the FBR was 243 ± 143 hydrated eggs per gram. The length at first maturity for males and females were 12.80 cm and 13.72 cm, respectively. In light of the study's results, it is recommended to develop a new fisheries management strategy aimed at contributing to the sustainability of whiting stocks in the Black sea. This strategy should consider the most efficient spawning periods identified in this study, as well as other reproductive strategies, and focus on preserving larger individuals that can enhance egg production within the stocks
The FIB-4 index is independently associated with QTc interval in patients with ankylosing spondylitis
No full textObjective: Prolongation of the QTc interval (QTc) is a known risk factor for ventricular arrhythmias and sudden cardiac death (SCD). Although ankylosing spondylitis (AS) is associated with systemic inflammation and metabolic alterations, data on the relationship between noninvasive fibrosis markers and QTc are limited. This study aimed to investigate the association between the FIB-4 index and QTc in patients with AS. Methods: A total of 82 consecutive patients with AS were enrolled in the study. Demographic characteristics, comorbidities, laboratory parameters, and medication use were also recorded. The FIB-4 index was calculated for each patient in the study. Surface 12-lead electrocardiograms were obtained, and the QTc was measured. Correlation analyses and multivariable linear regression models were used to identify the independent predictors of QTc. Results: The mean age of the study population was 42.4 ± 11.7 years, and 57.3% of the patients were men. Correlation analysis revealed significant associations between QTc and age, sex, the FIB-4 index, body mass index (BMI), hypertension, hyperlipidemia, and cardiovascular medication use, whereas hemoglobin and estimated glomerular filtration rate (eGFR) were negatively correlated with QTc. In the multivariable analysis, only sex (β = −0.306, p = 0.001) and the FIB-4 index (β = 0.379, p < 0.001) remained independently associated with QTc. Conclusion: Our findings demonstrate that the FIB-4 index is independently associated with the QTc in patients with AS. These results suggest that noninvasive fibrosis markers may provide additional insights into cardiovascular risk stratification in this population