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Widening the martensitic hysteresis ( T Dhys ) in NiTiNb shape memory alloys (SMAs) holds potential for broadening their working temperature range while enabling the room-temperature storage. In this study, the T Dhys is divided into two parts: the thermal-induced hysteresis ( T hys ) and the deformation-induced hysteresis ( T hys ′ ). In addition to decreasing the martensitic transformation start temperature ( M S ), it is found that grain refinement is an effective method for widening both T hys and T hys ′ of the Ni47Ti44Nb9 alloy, a commercial SMA widely used for shape memory couplings. According to thermodynamic analysis, grain refinement increases the dissipation energy ( Δ E dis ) (caused by thermal friction at martensite/austenite interface), thereby widening T hys . Moreover, the Ni47Ti44Nb9 alloy with finer grains has the potential to release more elastic strain energy ( Δ E el ) after deformation, thereby exhibiting a wider T hys ′ . When deforming a large strain, the alloy with finer grains generates more dislocations which stabilize the martensitic phase, thus further widening T hys ′ . [ABSTRACT FROM AUTHOR]

The maximum recovery stress is an essential parameter for evaluating the reliability of shape-memory alloys. In this study, the factors that determine the maximum recovery stress of the Ni47Ti44Nb9 shape-memory alloy were investigated. Although the recovery stress is generated by the shape recovery during constrained heating, the maximum recovery stress mainly depends on plastic deformation rather than the shape recovery strain. In the present work, because of the softening effect caused by dislocation annihilation and grain coarsening, plastic deformation occurs more easily with the increase in annealing temperature. This results in a sharp decrease in the maximum recovery stress, while the recovery strain remains high. [ABSTRACT FROM AUTHOR]

In this paper, the numerical simulation of sediment erosion and siltation near the Yellow River estuary is carried out by using wave, tidal current and sediment coupling model. A fine triangular mesh is used in the pattern to improve the spatial resolution of numerical calculations. Comparing the measured water depth data with the simulation results, the result shows that the simulation results are in good agreement with the actual situation. In order to analyze the influence of waves on sediment erosion and siltation, the paper carried out wave influence experiments under four conditions: no wind, north wind, easterly wind and south wind. The experimental results show that the wave has a great influence on the erosion and siltation of the seabed in the study sea area. Under the northward wave condition, an erosion zone is distributed in the SE-NW direction, and the maximum erosion thickness is about 1.9 m. Under the eastward wave condition, the erosion zone is north-south. The maximum scouring thickness is about 1.7 m; the scouring and silting effect under the southward wave condition is relatively weak. [ABSTRACT FROM AUTHOR]

OBJECTIVE: MiR-199 expression is associated with liver cancer. Bioinformatics analysis revealed that miR-199 has a complementary binding site to the 3’-UTR region of Snail mRNA. This study investigated whether miR-199 plays a role in regulating Snail expression and affecting epithelial-mesenchymal transition (EMT) and invasion of hepatoma cells. PATIENTS AND METHODS: The Dual-Luciferase reporter gene assay validated the targeted regulation between miR-199 and Snail. QRT-PCR was used to detect and compare the expression of miR-199 and Snail mRNA in human normal liver HL7702 cells, low metastatic MHCC97L cells, and high metastatic MHCC97H cells. MHCC97H cells were cultured in vitro and divided into two groups: miR-NC group and the miR-199 mimic group followed by the analysis of the expression of Snail, E-cadherin, and N-cadherin, as well as cell invasion ability by transwell assay. RESULTS: There was a targeted regulatory relationship between miR-199 and Snail mRNA. Compared with HL7702 cells, miR-199 expression was significantly decreased, and Snail expression was significantly increased in MHCC97L and MHCC97H cells, with more changes being observed in high metastatic MHCC97H cells. The transfection of miR-199 mimic significantly downregulated the expression of Snail and N-cadherin in MHCC97H cells, increased E-cadherin expression, inhibited the cell’s EMT process, and invasion. CONCLUSIONS: The decrease of miR-199 expression plays a role in upregulating the expression of Snail and promoting EMT and invasion of hepatocarcinoma cells. The increase of the expression of miR-199 can inhibit the expression of Snail and inhibit the EMT process and invasion ability of hepatoma cells. [ABSTRACT FROM AUTHOR]

A patient had right upper quadrant pain with sclera was transferred from emergency room to the hospital, she was proposed to have acute cholecystitis, gallstones, obstructive jaundice, and a four-year history of gallbladder stones. The NMR results showed that the gallbladder was significantly enlarged and the gallbladder wall was thickening irregularly. The liver morphology was not abnormal except with extensive intrahepatic bile duct dilatation. The MRCP results demonstrated that the intrahepatic bile ducts were significant expanded. The ERCP results showed that duodenal stenosis and extra-hepatic bile duct stenosis. We placed a plastic stent of 8.5Fr and 12 cm in length in the hepatic duct, and after biliary plastic stent placement, jaundice was rapidly reduced and liver function was improved significantly. A surgery was performed and the final pathologic diagnosis is a complication of Xanthogranulomatous cholecystitis with Mirizzi syndrome. After the surgery of cholecystectomy and a bile duct repair were performed, the patient was recovered well. Conclusively, if a patient was diagnosed as biliary stricture, a biliary metal stent should not be placed until pathological diagnosis of malignancy. [ABSTRACT FROM AUTHOR]