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Comparative analysis of cerebellar lobule structure in early, late bilinguals, and monolinguals: A cerebellum lobule-segmentation study
No full textThe structural changes in the cerebellum of early bilinguals (EBs) and late bilinguals (LBs) remain unclear, as learning a second language influences the brain. To explore how early bilingualism impacts cerebellar structure, we analyzed gray matter (GM) volume and cerebellar cortical thickness in individuals with EB, LB, and monolinguals (MLs). The T1-weighted images of 28 EB (English Spanish), 30 LB (English-Spanish), and 32 ML (English) participants were obtained from OpenNEURO (https://openneuro.org) and segmented using volBrain CERES 1.0 (https://volbrain.net/services/CERES) to compare cerebellar GM volume and cortical thickness. We performed cerebellum lobule-wise segmentation analysis on groups matched for age, education, and gender. We found that, compared to the ML group, the LB group showed a larger GM volume in the right lobule III, and compared to the EB group, the LB group had greater cortical thickness in the left lobule IX. No other significant differences were found among the groups. Although there was a positive correlation between the age of second language acquisition and lobule IX cortical thickness in participants from the EB and LB groups no other significant differences were observed among the groups. In summary, by examining the structural differences in cerebellar GM volume and cortical thickness among EBs, LBs, and MLs, we found that later second-language acquisition is linked to increased GM volume in right lobule III and greater cortical thickness in left lobule IX. These findings suggest experience-dependent cerebellar plasticity related to the age at which second language acquisition occurs
Primary Adrenal Sarcomas: Diagnostic Challenges and Therapeutic Insights From a Case Series Including Leiomyosarcoma and Epithelioid Angiosarcoma
No full textPrimary adrenal leiomyosarcoma and primary adrenal epithelioid angiosarcoma are exceptionally rare mesenchymal tumors of the adrenal gland. Both typically present as unilateral, nonfunctional adrenal masses and may closely resemble other adrenal or metastatic tumors, thus making diagnosis challenging. Immunohistochemical analysis is essential for accurate classification and clinical decision-making. We report two primary adrenal leiomyosarcomas and one primary adrenal epithelioid angiosarcoma, all occurring in elderly female patients without initial evidence of extra-adrenal disease. The leiomyosarcomas demonstrated spindle cell morphology with strong expression of smooth muscle markers and variable proliferative activity, including one patient that progressed to hepatic metastasis. The epithelioid adrenal angiosarcoma exhibited epithelioid features, extensive necrosis, diffuse CD31 and ERG positivity, and focal keratin expression. Complete surgical resection was achieved in all patients. These patients highlight the diagnostic complexity and prognostic variability of adrenal sarcomas. Documenting such rare tumors remains critical to improving diagnostic precision and guiding optimal management strategies
TAKVİYELİ ÖĞRENME VE AÇIKLANABİLİR YAPAY ZEKA İLE SANAL KAN ŞEKERI İZLEME SİSTEMİN GELİŞTİRMESİ
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Experimental investigation of momentum ratio and Weber number influence on droplets' characteristics for jet in cross-flow
No full textIn this study, the droplet size and velocity distributions resulting from liquid jet and sheet injections into a cross-flow were investigated. Since previous research has provided limited insights into the effects of rectangular nozzles compared to circular ones, this study tested four different nozzles-two circular and two rectangular-each with distinct hydraulic diameters. This design aimed to explore the influence of nozzle geometry and hydraulic diameter on droplet size and velocity distributions. To assess the effects of liquid and gas flow conditions on the microscopic properties of droplets, the cross-flow Weber number ranged from 6 to 15, while the injection fluid Weber number varied from 90 to 1100. Additionally, measurements were conducted at varying distances and spatial positions relative to the spray nozzle, capturing threedimensional spatial distributions of the studied parameters. An experimental methodology was employed to measure droplet size and velocity. The test setup was equipped with high-precision imaging capabilities and the shadowgraphy technique was utilized for droplet visualization. The collected data were analyzed using data analysis approaches, including analysis of covariance, multiple linear regression, and standard statistical tests. The investigation into the effects of flow conditions on droplet size revealed that the momentum ratio between the injected fluid and the cross-flow plays a critical role, with higher momentum ratios resulting in smaller droplet sizes. Furthermore, the study identified a critical gas Weber number and a universal critical momentum ratio, highlighting a dual-effect mechanism of the cross-flow on droplet diameter. This novel finding and its underlying physics, to the authors' knowledge, have not been explicitly reported in prior research. The analysis also demonstrated that increasing the Weber number of either the injected fluid or the cross-flow increases the velocity of the produced droplets. A general inverse relationship between droplet size and velocity was observed. Regarding nozzle effects, the results indicate that rectangular nozzles produce smaller droplets, while larger hydraulic diameters yield larger droplet sizes. Finally, power-law relationships were developed to describe the distributions of droplet size and velocity as functions of flow conditions and spatial position for each nozzle type
Pestle analysis of digitalization in aviation safety
No full textAviation sector is undergoing a radical transformation in line with the digitalization offered by Industry 4.0. Artificial intelligence, big data analytics, the Internet of Things (IoT) and sensor-based systems provide significant contributions in critical areas such as increasing flight safety, improving maintenance processes and managing crisis moments. Simulations based on augmented and virtual reality technologies reduce human error by providing effective learning environments in the training of pilots and technical personnel. On the other hand, digital air traffic management and satellite-based navigation systems optimize collision prevention and airspace efficiency. These technologies both increase operational efficiency and contribute to environmental sustainability goals. However, as digitalization progresses, the interconnectedness of systems has brought new security threats such as cyber attacks, data breaches and technical failures. In particular, inadequate regulations and incompatibilities in international standards make it difficult to use these technologies safely and widely. This study examined technological components and operational processes within the framework of the Aviation 4.0 concept and evaluated the effects of digitalization on aviation safety using literature review and PESTLE analysis and word frequency analysis methods. The results show that digital technologies offer significant opportunities to the sector, but structural risks and regulatory gaps need to be taken into account for a sustainable security management
