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Investigation of the relationship between background parenchymal enhancement and breast cancer using 3.0 Tesla magnetic resonance imaging
No full textAim This study aims to explore the correlation between background parenchymal enhancement (BPE) observed in breast magnetic resonance imaging (MRI) and the presence of breast cancer. Materials and methods A total of 761 patients (326 malignant, 435 benign) who underwent breast MRI on a 3 T MRI device between August 2019 and August 2022 were included in the study. In breast MRI, the rate of fibroglandular tissue (FGT), areas of mass/non-mass enhancement in malignant cases, and BPE in the initial post-contrast series were evaluated. In addition to the clinical and demographic data of the patients, pathology results were added to the dataset. Molecular subtyping was categorized based on immunohistochemical markers into Luminal-A, Luminal-B (HER-2 negative), Luminal-B (HER-2 positive), HER-2 positive, and triple-negative groups. Results In the evaluation of BPE, minimal-to-mild enhancement was more common in both groups. No significant relationship was observed between BPE and menstrual cycle timing, cancer association, lesion characteristics, and pathological results. No significant intergroup difference was observed between FGT and BPE in the malignant and benign groups. The mean age of patients with moderate-to-marked background enhancement was significantly lower ( p = 0.036). When the relationships between background enhancement and other descriptive features were evaluated, no statistically significant relationship was found. Conclusion The findings of our study suggest that BPE in breast MRI is not a determining factor in the diagnosis of breast cancer in patients with average or low risk
Investigation of the chemical profile and biological properties of the genera grimmia and dicranum
No full textEssential oils (EOs) are a significant component of herbal medicine worldwide. However, the components of the EOs from Grimmia orbicularis Bruch ex Wilson, Grimmia alpestris Schleich, Grimmia ovalis (Hedw.) Lindb., Grimmia lisae De., Dicranum scoparium Hedw., Dicranum majus Sm., Dicranum polysetum Sw. and Dicranum spadiceum J.E. Zetterst., as well as the antimicrobial activity of eight moss EOs and methanol extracts (MEs), and the antioxidant, anti-urease, anti-xanthine oxidase (XO) activity and total phenolic content (TPC) of MEs from these eight moss species have not yet been systematically evaluated. The composition of the EOs was determined using the GC/FID/MS method. The antioxidant activities of MEs from eight mosses were assessed using the FRAP and DPPH methods. In addition, the MEs of these eight mosses were analysed for TPC, urease and XO activity using a reference. A total of 80 compounds were identified in the EOs of the eight mosses, including mainly aldehydes (7.3%–95.3%), monoterpene hydrocarbons (53.7%–60.6%), oxygenated monoterpenes (0.2%–16.7%) and terpene-related compounds (1.3%–51.2%). The methanol extract of D. scoparium (FRAP: 341.107 ± 1.248 μmol; DPPH SC50: 0.145 ± 0.005 mg/mL) exhibited the highest antioxidant activities, surpassing even Trolox. Furthermore, the methanol extract of D. scoparium significantly inhibited urease and XO, with IC50 values of 2.542 ± 0.023 μg/mL and IC50: 7.652 ± 0.054 μg/mL, respectively. The chemical composition of the EOs of these eight mosses is presented. Additionally, the biological activities were evaluated, confirming the ethnopharmacological use of these mosses based on their biological properties
Enhancing the performance of conical solar stills through optimised flint stone placement on absorber
No full textWater shortage is a significant global issue, necessitating the development of sustainable, energy-efficient desalination technologies. This study aims to determine the optimal spacing of 2 cm diameter flint stones to enhance the efficiency of conical solar stills. Three identical stills were tested over two days: the first had no stones, the second had stones spaced 3 cm apart (61 stones), and the third had stones spaced 4 cm apart (41 stones). On the second day, the first still remained stone-free, while the second and third stills had stones with 5 cm (25 stones) and 6 cm (13 stones) spacing, respectively. The results indicated that the system with 3 cm stone spacing achieved the highest water productivity, yielding 8600 g/m2, significantly surpassing the other configurations: 4 cm (7850 g/m2), 5 cm (7400 g/m2), 6 cm (6900 g/m2), and the baseline system (5600 g/m2). The optimal distance of 3 cm resulted in a 53.57 % improvement over the conventional system. Performance analysis further revealed enhancements across thermodynamic indicators, with the system at 3 cm spacing exhibiting a 56.68 % increase in efficiency, a 190.64 % improvement in exergy efficiency, and a 163.03 % rise in exergy production compared to the baseline. These improvements are attributed to better heat retention and optimized heat transfer dynamics from closer stone placement. The study concludes that using flint stones with a 2 cm diameter and a spacing of 3 cm significantly enhances system performance, offering a scalable and low-cost solution for solar-powered desalination in arid regions
Emerging trends and bibliometric analysis of internet of medical things for innovative healthcare (2016–2023)
No full textBackground: The internet of medical things (IoMT) is revolutionizing digital health through continuous monitoring, real-time diagnostics, and remote care capabilities. Nonetheless, research in this domain remains disjointed, with a restricted comprehension of its growth trajectories, principal contributors, and thematic emphasis. A comprehensive evaluation is thus required to inform forthcoming research, policy, and advancements in resilient healthcare technologies. Methods: This study performed a bibliometric and literature-based analysis of IoMT research indexed in the Scopus database from 2016 to 2023. The dataset was optimized by keyword screening, resulting in 762 pertinent papers. Bibliometric indices, including as publication and citation trends, authorship and institutional output, and funding patterns, were analyzed. Thematic evolution was examined by keyword co-occurrence and cluster mapping utilizing VOSviewer, complemented by a synthesis of literature. Results: A total of 762 publications on IOMT were identified, comprising 63.12% journal articles, 30.97% conference papers, and 5.91% review papers. The total publications rose from 1 in 2016 to 301 in 2023, indicating a 30,000% increase. Total citations reached 19,014, with an h-index of 171. The most prolific contributors were Mohsen M. Guizani, King Saud University, and India. Collaborations and funding, particularly from international agencies, were found to significantly drive research productivity. Keyword and cluster analyses revealed two dominant thematic areas: Smart Medical Diagnostics and Privacy-Driven Health Technologies. The literature further confirmed strong integration of machine learning, blockchain, sensor technologies, and cloud computing in IOMT applications. Conclusion: This analysis consolidates fragmented IoMT research, providing a structured overview of its development, contributors, and thematic trajectories. The findings highlight the rapid growth, global collaborations, and integration of advanced technologies driving the field. By mapping benchmarks and research hotspots, the study offers valuable evidence to guide future investigations, interdisciplinary collaborations, and policy efforts aimed at strengthening secure and patient-centered digital health systems
Lesion detection using artificial intelligence models in MR images of prostate cancer and prostatitis patients and comparison of model performance
No full textAim: The diagnosis of prostate cancer and prostatitis becomes challenging when using biparametric Magnetic Resonance (MR) images. This research investigates deep learning models to assess their capability for improving diagnostic accuracy and assisting radiologists. Methods: This retrospective study analyzed 153 patients who received histopathological diagnoses of prostate cancer or prostatitis between January 2017 and December 2023. Patients were categorized according to PI-RADS scores, and both T2A and ADC-DWI (Apparent Diffusion Coefficient–Diffusion-Weighted Imaging) sequences were examined. Expert radiologists labeled the images prior to lesion detection with the Faster R-CNN (Faster Region-based Convolutional Neural Network) model. Nine different classification models were trained using normal and augmented datasets to evaluate their performance. Model reliability was further assessed through cross-validation and statistical significance testing. Results: The Faster R-CNN model achieved 96% accuracy (95% CI: 93.2–98.8%) for P5 and 99% accuracy (95% CI: 96.7–100%) for prostatitis in T2A sequences, and 90% accuracy (95% CI: 85.4–94.6%) for P5 and 97% accuracy (95% CI: 93.8–100%) for prostatitis in ADC-DWI sequences. However, the model failed to effectively detect P4 lesions (0% sensitivity in T2A and 30% in ADC-DWI). The model demonstrated comparable performance to expert radiologists, with no significant difference in overall P5 detection (p > 0.05), and Cohen’s kappa indicated substantial agreement (κ = 0.86). The classification models achieved up to 97% accuracy with InceptionV3 in T2A sequences and up to 99% accuracy with DenseNet201 in ADC-DWI sequences. To further evaluate discriminative performance, AUROC values were calculated for all classification models. In T2A sequences, AUROC scores were DenseNet201 (0.98), EfficientNetV2L (0.99), InceptionV3 (0.99), MobileNetV2 (0.92), NASNetLarge (0.83), ResNet50 (0.76), VGG16 (0.98), VGG19 (0.97), and Xception (0.96). In ADC-DWI sequences, AUROC values were DenseNet201 (0.99), EfficientNetV2L (0.96), InceptionV3 (0.99), MobileNetV2 (0.82), NASNetLarge (0.90), ResNet50 (0.64), VGG16 (0.96), VGG19 (0.86), and Xception (0.97), reinforcing the superior discriminative ability of DenseNet201 and InceptionV3 across modalities. Conclusion: The deep learning models demonstrated promising diagnostic capabilities, comparable to radiologists, in distinguishing prostatitis and P5 prostate cancer lesions. Overall, the findings suggest that AI-based diagnostic tools hold potential as clinical decision support systems
Evaluation of the frequency, risk factors and outcomes of ROP in preterm infants with a BW >1500 g or GA >32 weeks in Turkiye (TR-ROP 2) and medicolegal fears: a Turkish Neonatal Society multicentre study
No full textBackground This study aimed to evaluate the prevalence and risk factors of retinopathy of prematurity (ROP) in preterm infants with a birth weight (BW)>1500 g or gestational age (GA) >32 weeks in Turkiye. Methods A prospective cohort study (TR-ROP 2) was conducted in 80 neonatal intensive care units between 30 September 2023 and 1 November 2024. Infants with a BW >1500 g or GA >32 weeks who had an unstable clinical course or were deemed at risk for ROP were included. The effect of medicolegal concerns on the decision to screen was also evaluated. Results The study included 4140 infants at risk for ROP development; 242 (5.8%) developed any stage of ROP, and 17 (0.4%) developed severe ROP requiring treatment. Risk factors independently associated with ROP included lower GA and BW, being small for GA, red blood cell transfusion, oxygen therapy >5 days, mechanical ventilation >1 day, early neonatal sepsis (ENS) with comorbidities or presence of ≥3 comorbidities (excluding ENS). Of those with BW ≥2000 g, 31.4% were screened for medicolegal reasons; 2.2% developed ROP, but none had severe ROP. Conclusions ROP in mature infants is rare but can occur in the presence of multiple risk factors. Medicolegal concerns may contribute to overscreening. Developing evidence-based, risk-adapted screening guidelines is essential to ensure appropriate care without unnecessary interventions
New sequence spaces generated via a matrix defined by schröder and catalan numbers
No full textThis study introduces the sequence spaces c(S star) and c0(S star), defined as the domain of the matrix S star constructed from a hybrid structure involving Schr & ouml;der and Catalan numbers. A comprehensive investigation is conducted into the fundamental topological and structural properties of these sequence spaces, such as completeness and their relationships and embedding within classical sequence spaces. Furthermore, the dual space structures corresponding to these newly defined spaces are thoroughly characterized. In the final sections, various classes of matrix transformations and compact linear operators acting on these sequence spaces are examined, emphasizing their significance in functional analysis
Sustainable stabilization of sulfidic mine tailings using fly ash and sodium bicarbonate: A multiscale analysis
No full textCementitious filling technique is an imperative measure for sustainable disposal and utilization of tailings. Considering that high‑sulfur tailings can cause acid corrosion and sulfate erosion, thereby reducing the stability of high‑sulfur tailings backfill (CHSTF), the introduction of alkaline additives is of significant importance. Based on this, the current research investigated the impacts of fly ash (FA) and sodium bicarbonate (SOB) alkaline admixtures on the macro and micro properties, as well as the chemical stability of CHSTF specimens. A comprehensive evaluation was conducted using uniaxial compression tests (UCS), chemical stability analysis (pH, sulfate ion concentration, conductivity), and microstructural characterization (SEM-EDS, XRD, FTIR). Experimental results indicate that adding alkaline agents realistically improves CHSTF's performance. Specifically, when FA and SOB were added simultaneously at a dosage of 1 wt%, the maximum UCS value reached 3.20 MPa, representing a 73 % increase in strength compared to the control group, while also enhancing chemical stability and promoting the formation of a dense microstructural network. Notably, the synergistic mechanism between FA's volcanic ash reaction and SOB's early alkaline buffering effect was elucidated. Ultimately, this research contributes significantly to the sustainable treatment of sulfur-containing tailings and offers a theoretical basis and practical support for global mine backfilling engineering applications
A review on microplastics in bivalves: analysis, quantification, and effects
No full textMicroplastics (MPs) contamination poses serious risks to aquatic ecosystems and food security, as bivalves and other marine organisms easily ingest these particles. Bivalves are of particular concern due to their ecological roles, wide distribution, and importance in the human diet. To better understand the bioaccumulation of MPs and contamination in the food chain, we reviewed 56 published articles (2016–2024), including experimental studies, biomonitoring, and prevalence of MPs, using keywords related to microplastics, bivalves, abundance, shape, and color. Overall, the reviewed studies indicate that bivalves accumulate a variety of microplastic forms, with fibers consistently dominating fragments and other morphologies. Polystyrene and polypropylene were the most commonly reported polymers, while black and white particles represented the most common colors. Reported loads of MPs varied considerably across species and geographic regions, reflecting differences in local sources such as fishing gear, textiles, and human activities. These findings underscore the role of bivalves as reliable bioindicators of MPs pollution, and emphasize their importance not only in monitoring ecosystem health but also in informing management strategies and safeguarding food security
Current activity concentrations of 226Ra, 232Th, 40K and 137Cs in beach sand samples from various coastal regions of Türkiye and associated health risk assessment
No full textIn this study, gamma-spectrometry was used to determine the concentrations of 226Ra, 232Th, 40K, and 137Cs radioactivity in surface beach. Samples were collected from thirty-one coastal beaches across various cities in Türkiye. The results obtained were evaluated in the context of four geographical regions: Black Sea, Mediterranean, Marmara and Aegean. In all samples, the maximum, minimum, and mean activity concentration values were 66.06 ± 0.89, 1.07 ± 0.10, and 11.65 ± 0.39 Bq kg−1 for 226Ra; 43.04 ± 1.21, 0.76 ± 0.10, and 7.35 ± 0.41 Bq kg−1 for 232Th; and 657.39 ± 6.57, 27.54 ± 1.30, and 260.31 ± 4.06 Bq kg−1 for 40K, respectively. The maximum, minimum and mean activity concentration values of the anthropogenic 137Cs isotope were 6.53 ± 0.25, 0.3 ± 0.05 and 2.38 ± 0.17 Bq kg−1, respectively. The average values of radiological hazard indices such as equivalent radium activity, external(internal) hazard index, outdoor absorbed gamma dose rate and annual effective dose equivalent were calculated as 42.20 Bq kg−1, 0.11(0.15), 20.67 nGy h−1, 0.025 mSv y−1, for all samples respectively. The calculated radiological hazard indices were below the world averages and did not pose any significant health risk to beachgoers