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Segregation is a serious defect in alloy ingots which severely deteriorates materials performance. The segregation defect in Mg-6Gd alloy is studied by coupling macro thermal-solutal-convection transport and micro dendrite growth. The macroscopic fluid dynamics and mass transfer equations are resolved to forecast the segregation behavior under conditions of continuous temperature variation during the solidification process. The numerical model is validated by testing double-diffusive natural convection in a closed square cavity. A phase field model is then applied to simulate the micro dendrite growth, using macro undercooling and liquid flow velocity as boundary conditions. Results show that the multiscale segregation behavior, including macro solute distribution and micro dendritic morphology, is strongly dependent on the temperature condition and the liquid convection, which provides guidance for reducing and eliminating the segregation defect. [ABSTRACT FROM AUTHOR]

Bud sport is a common and stable somatic variation in perennial fruit trees, and often leads to significant modification of fruit traits and affects the breeding value. To investigate the impact of bud sport on the main metabolites in the fruit of white-fleshed loquat, we conducted a multi-omics analysis of loquat fruits at different developmental stages of a white-fleshed bud sport mutant of Dongting loquat (TBW) and its wild type (TBY). The findings from the detection of main fruit quality indices and metabolites suggested that bud sport resulted in a reduction in the accumulation of carotenoids, fructose, titratable acid and terpenoids at the mature stage of TBW, while leading to the accumulation of flavonoids, phenolic acids, amino acids and lipids. The comparably low content of titratable acid further enhances the balanced and pleasent taste profile of TBW. Expression patterns of differentially expressed genes involved in fructose metabolism exhibited a significant increase in the expression level of S6PDH (EVM0006243, EVM0044405) prior to fruit maturation. The comparison of protein sequences and promoter region of S6PDH between TBY and TBW revealed no structural variations that would impact gene function or expression, indicating that transcription factors may be responsible for the rapid up-regulation of S6PDH before maturation. Furthermore, correlation analysis helped to construct a comprehensive regulatory network of fructose metabolism in loquat, including 23 transcription factors, six structural genes, and nine saccharides. Based on the regulatory network and existing studies, it could be inferred that transcription factors such as ERF, NAC, MYB, GRAS, and bZIP may promote fructose accumulation in loquat flesh by positively regulating S6PDH. These findings improve our understanding of the nutritional value and breeding potential of white-fleshed loquat bud sport mutant, as well as serve as a foundation for exploring the genes and transcription factors that regulate fructose metabolism in loquat. [ABSTRACT FROM AUTHOR]

Background: Few studies have examined seizures in pediatric brain arteriovenous malformation. In our study, risk factors associated with seizure occurrence and long-term seizure control outcomes after different treatments in pediatric arteriovenous malformation patients were investigated. Methods: A retrospective analysis was conducted with clinical data from a cohort of 89 pediatric brain arteriovenous malformation patients acquired between 2008 and 2013. Univariate and multivariate analyses were used to assess risk factors associated with seizure incidence. Patients who presented with seizure before treatment were evaluated using the Engel classification during the follow-up period. Results: A higher risk of seizure occurrence was observed in large size and unruptured brain arteriovenous malformations using multivariate logistic regression analysis (p < 0.05). A total of 22 children, who presented with seizure before the interventions, were included in subsequent analysis. During a mean follow-up period of 2.3 years after the intervention, 12 (55 %) of these children were classified as Engel class I after treatment. Conclusions: Seizures were the most common symptom in unruptured bAVMs. Size of the brain arteriovenous malformation is highly significant to seizure occurrence. Patients with cerebral hemorrhage are prone to having an acute seizure occurrence. The different therapies examined all improved seizure control to varying degrees. [ABSTRACT FROM AUTHOR]

Central hepatectomy is amongst the most difficult surgeries of liver tumors. For the routine local excision of a tumor, if the tumor has invaded the blood vessels or bile duct of the liver, then half of the liver or three lobes of the liver are resected. This results in two major drawbacks, one of which is that the residual hepatic lobe may not compensate for the damage, so it is not possible to perform conventional partial resection. The other is that the volume of normal liver tissue removed may be much more than the volume of tumor removed, causing substantial waste. In the present study, surgery was performed to resect a central liver tumor. In that surgery, the V segment and parts of the IV, VI and VIII segments were resected, and the blood supply and biliary drainage of the left hepatic lobe were kept intact. However, for the remaining VI, VII and VIII segments of the right hepatic lobe, only the blood supply from the portal vein was maintained and no arterial blood supply or biliary drainage was kept so that the patient had the opportunity to undergo radical resection and successful rehabilitation. The reason these opportunities may be possible is that the residual right liver is a temporary replacement therapy in the perioperative period. Therefore, for central hepatic tumors, particularly tumors that have invaded the neighboring bile ducts or blood vessels, if the blood supply and biliary drainage on one side is maintained and the blood supply to the other side from the portal vein is kept intact, then it is possible to perform radical resection. This provides a novel approach to the clinical resection of central liver tumors. [ABSTRACT FROM AUTHOR]