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The negative strain rate sensitivity (SRS) of metallic glasses is frequently observed. However, the physical essence involved is still not well understood. In the present work, small-angle X-ray scattering (SAXS) and high-resolution transmission electron microscopy (HRTEM) reveal the strong structure heterogeneity at nanometer and tens of nanometer scales, respectively, in bulk metallic glass (BMG) Zr64.13Cu15.75Ni10.12Al10 subjected to fully confined compression processing. A transition of SRS of stress, from 0.012 in the as-cast specimen to −0.005 in compression processed specimen, was observed through nanoindentation. A qualitative formulation clarifies the critical role of internal stress induced by structural heterogeneity in this transition. It reveals the physical origin of this negative SRS frequently reported in structurally heterogeneous BMG alloys and its composites.

Zr52.5Cu17.9Al10Ni14.6Ti5 (Vit105) Bulk metallic glass is processed by High-Pressure Torsion up to 30 rotations at room temperature, showing simultaneous enhancement of both strength (2023 MPa) and ductility (0.45%). Nano-crystal precipitates with an average size of 45 nm inside the amorphous matrix are observed after 30 turns HPT. Free volume increases from ~0.9030 A3 (as cast) to ~0.9275A3 after 30 turn HPT alloy with 2.83% (by volume) of nanocrystal precipitates. Strengthening due to precipitation after 30 turns HPT comply with the phase mixture model. The synergetic effect of free volume and nanocrystal precipitation on the ductility of amorphous-crystallite composite is quantitatively approached through modelling. By implementing the model, a ductilization window between bottom limit and top limit of the inter-crystallite spacing w.r.t the free volume is established, elucidating the necessary conditions required to obtain plasticity in amorphous-crystalline composites.

The cable support system in large cross-section cable tunnel, which can solve the cable laying problem of big cross section cable and multi-loop cable effectively, gradually become the development trend of urban electricity transmission. Combined with the structure feature of large cross section shield tunnel, a new type of self-balanced shield tunnel cable support system is proposed. The safety and rationality of this system has been validated by the structure calculation, the finite element analysis of ADINA and the full scale model test. The analysis shows that the system has some advantages, such as excellent whole mechanical characteristics, strong adaptability, convenient construction and low cost. The system can fully satisfy all requirements of the cable tunnel construction and all functions of operation. The stress distribution of the structure is relatively homogeneous, the bearing capacity of components and the global stability of it also meet the requirements. With the test load which is about 1.5 ~ 4.0 times as large as design load, the support system displacement is 0.65 ~ 2.5 mm, which shows that the structure is safe and reliable. The research achievements can provide theoretical basis and experimental basis for the design of large cross-section cable tunnel.

Biliary tract cancers, broadly described as malignancies that arise from the biliary tract epithelia, are usually divided into two major clinical phenotypes: cholangiocarcinoma and gallbladder cancer, differing in etiopathogenesis, risk factors, and perhaps molecular and genetic signatures. Atypical symptoms and lack of tumor biomarkers make it difficult to diagnose in early stages. At the time of presentation, few patients are candidates for potentially curative surgical resection. We here assessed and compared features of a total of 150 cases divided into extra- and intrahepatic cholangiocarcinomas and gallbladder cancers (GBC). Althought there were no significant differences in serum tumour marker levels, GBC patients had the poorest prognosis. Furthermore, gallbladder cancer respond poorly to chemotherapy or radiation therapy and approximately half of untreated patients died within 10 months. Therefore, treatment for patients with gallbladder cancer is still in challenge. Outcomes and survival of these patients had improved little over the past three decades - a period in which new successful treatments have greatly contributed to the prolonged patient survival for many other cancers.

Considerable effort has been made in elucidating the appropriate biomarkers and the mechanism and functional significance of these biomarkers in hepatocellular carcinoma (HCC). Glycoprotein nonmetastatic B (GPNMB) overexpression occurs in cutaneous melanomas and breast cancer, and it is an attractive candidate for cancer therapy. However, little is known about the expression and regulation of GPNMB in HCC. In this study, we investigated the expression of GPNMB in HCC histochemically and tested the regulation effects of the epithelial cell adhesion molecule (EpCAM) and colony-stimulating factor (CSF-1) on the expression of GPNMB in HCC cells. Our results demonstrated that GPNMB levels were significantly enhanced in HCC compared with adjacent normal liver tissues. In HCC cells, GPNMB expression was regulated by EpCAM and CSF-1 partly through their common downstream product c-myc. Taken together, these results suggest that GPNMB, the expression of which was regulated in HCC cells by the highly coordinated function of various proteins, may be a potential target for HCC therapy.

Objective: To improve the diagnosis of primary gallbladder carcinoma (GBC) with/without hepatic metastases by analyzing our experience of different GBC treatment in our patients. Methods: A retrospective study was carried out to analyze the clinical data of the 139 patients with GBC who underwent hepatic resection in our unit from January 2003 to December 2007. Patients were divided into two groups according to whether they demonstrated hepatic invasion. Tumor presentation, surgical modes, and prognosis of each patient were retrospectively reviewed. Kaplan-Meier curves and log-rank tests were employed to compare the survival rates of those patients undergoing different surgical procedures. Results: Of the 139 patients, 46 were men and 93 were women with the male to female ratio of 1:2.0. Their ages were ranged from 35 to 86 years with a mean age of 62.8±10.4 years. There were 73 patients complicated with hepatic invasion (group A), and no hepatic invasion occurred in the other 66 patients (group B). Compared with the group B, the patients with hepatic invasion suffered lower differentiation of tumor (p=0.000), more advanced Nevin staging (p=0.008) and poorer prognosis (p=0.013). Radical resection were more frequently performed in group B (75.76%) than in group A (45.20%) with better outcomes (p=0.000). Conclusion: GBC patients complicated with hepatic invasion had poorer prognosis than those without invasion in long-term follow-ups. Radical resection might result in a satisfied prognosis in patients without hepatic invasion, but appears less favorable than palliative resection in those who were complicated with hepatic invasion.

Serum alpha-fetoprotein (AFP) is a significant marker for clinical diagnosis and prognosis evaluation in hepatocellular carcinoma (HCC) patients. However, some proportion of liver cancer patients are AFP-negative (AFP ≤20 ng/ml). In order to study the differences between clinicopathological factors and prognosis of alpha-fetoprotein negative and positive patients, a total of 114 cases (41 AFP-negative and 73 AFP-positive) were selected for our research. By systematically statistical analysis, the results demonstrated that compared with AFP-negative patients, AFP-positive examples were more likely to feature cirrhosis nodules, non-complete neoplasm capsules, and a poor Edmondson-steiner grade. Furthermore, AFP-negative patients demonstrated a favorable long-term prognosis. By univariate analysis and multivariate analysis with Cox's proportional hazards model, multiple tumors were found to be independent risk factors for worse survival of AFP negative patients; however, less tumor-free margins, multiple tumors and Edmondson-steiner grades III/IV, proved to be independent risk factors leading to a poor prognosis of AFP positive cases. Finally, we can infer that high levels of AFP signify a highly malignant tumor and unfavorable prognosis.

Whether an additional Braun enteroenterostomy is necessary in reducing delayed gastric emptying (DGE) after pancreaticoduodenectomy (PD) has not yet been well investigated. Herein, in this retrospective study, 395 consecutive cases of patients undergoing classic PD from 2009 to 2013 were reviewed. Patients with and without Braun enteroenterostomy were compared in preoperative baseline characteristics, surgical procedure, postoperative diagnosis, and morbidity including DGE. The DGE was defined and classified by the International Study Group of Pancreatic Surgery recommendation. The incidence of DGE was similar in patients with or without Braun enteroenterostomy following PD (37/347, 10.7% vs 8/48, 16.7%, P = 0.220). The patients in the 2 groups were not different in patient characteristics, lesions, surgical procedure, or postoperative complications, although patients without Braun enteroenterostomy more frequently presented postoperative vomiting than those with Braun enteroenterostomy (33.3% vs 15.3%, P = 0.002). Bile leakage, pancreatic fistula, and intraperitoneal abscess were risk factors for postoperative DGE (all P