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In engineering practice, layered rock masses often display obvious anisotropy while deforming and failing, and the failure mode directly impacts the engineering construction stability. In this study, the fracture failure load, fracture toughness, crack deflection angle, and failure mode of a layered rock mass under different fracture modes were analyzed by utilizing improved asymmetric semi-circular disc specimens. According to the constitutive model of transversely isotropic materials, the maximum tensile stress (MTS), maximum energy release rate (MERR), and maximum strain energy density (MSED) calculation formulas were modified, and the calculation formulas of the three prediction criteria under anisotropic materials were derived. The calculation results were compared with the experimental results. The results show that the fracture toughness and crack deflection angle were significantly affected by the weak bedding plane. As a result of applying the MTS criterion, the results are closer to the experimental results, providing a solid foundation for engineering deformation, failure, and fracture analyses. [ABSTRACT FROM AUTHOR]

The theoretical model for group-forced infragravity (IG) waves in shallow water is not well established for nonbreaking conditions. In the present study, analytical solutions of the group-forced IG waves at O(β1) (β1 = hx/(Δkh), hx = bottom slope, Δk = group wavenumber, h = depth) in intermediate water and at O ⁡ (β 1 − 1 ) in shallow water are derived separately. In case of off-resonance [β1μ−1 = O(β1), where μ = 1 − c g 2 / (g h) is the resonant departure parameter, cg = group speed] in intermediate water, additional IG waves in quadrature with the wave group forcing (hereinafter, the nonequilibrium response or component) are induced at O(β1) relative to the equilibrium bound IG wave solution of Longuet–Higgins and Stewart (1962) in phase with the wave group. The present theory indicates that the nonequilibrium response is mainly attributed to the spatial variation of the equilibrium bound IG wave amplitude instead of group-forcing. In case of near-resonance [β1μ−1 = O(1)] in shallow water; however, both the equilibrium and nonequilibrium components are ~ O ⁡ (β 1 − 1 ) at the leading order. Based on the nearly-resonant solution, the shallow water limit of the local shoaling rate of bound IG waves over a plane sloping beach is derived to be ~h−1 for the first time. The theoretical predictions compare favorably with the laboratory experiment by Van Noorloos (2003) and the present numerical model results generated using SWASH. Based on the proposed solution, the group-forced IG waves over a symmetric shoal are investigated. In case of off-resonance, the solution predicts a roughly symmetric reversible spatial evolution of the IG wave amplitude, while in cases of near to full resonance the IG wave is significantly amplified over the shoal with asymmetric irreversible spatial evolution. [ABSTRACT FROM AUTHOR]

The present paper aims to clarify the mechanism of infragravity wave (IGW) energy amplification over nearshore shoals reported in recent studies. Wave transformation and energy transfer between short waves (SWs) and IGWs were investigated using SWASH model for nonbreaking random waves propagating over trapezoid shoals with different bottom slopes. It was found that the time lag of IGWs relative to SW groups is the major mechanism for energy transfer from SWs to IGWs and the amplification of IGW energy over all segments of the shoal. The time lag is generated on the front slope and enlarged on the plateau of the shoal, decreases on the rear slope with higher decreasing rates on milder slopes. Over the rear slope, the evolution of IGWs depends on the relative importance of deshoaling and nonlinear energy transfer. It was found that nonlinear energy transfer dominates over the rear slope gentler than 1/60, causing the IGW energy to increase over the first half of the deshoaling process and decrease over the second half whereas deshoaling dominates for steeper rear slope and the IGW energy decay over the whole slope. It is demonstrated numerically and theoretically that the shoals with gentler bottom slopes amplify the IGW energy more effectively by providing longer distance for nonlinear energy transfer to build up. The persistent nonlinear energy transfer on the plateau indicates the important role of wave spatial evolution history in the subsequent IGWs evolution. Strong free IGWs were detected on leeward of the shoal, possibly due to release of topography‐induced additional bound IGWs. Key Points: Wave spatial evolution history has significant effects on the subsequent evolution of infragravity wavesInfragravity wave energy is significantly amplified in the direction of wave propagation by a near shore shoalShort waves continually transfer energy to infragravity waves when propagating across the shoal even in the deshoaling zone [ABSTRACT FROM AUTHOR]

NUT carcinoma (NC) is an aggressive squamous tumor characterized by NUT gene rearrangement, and the most common fusion form is BRD4-NUT. However, NC diagnosis is difficult for its rareness and often being confused with a variety of poorly differentiated tumors. A 21-year-old Chinese woman was referred to our hospital for cough and intermittent fever. Chest computed tomography (CT) imaging revealed a left lobe hilar mass. Fiberoptic bronchoscopy results showed that tumor cells were poorly differentiated. In combination with immunohistochemistry staining, she was misdiagnosed with Ewing's sarcoma/primitive neuroectodermal tumor. Next-generation sequencing (NGS) revealing BRD4-NUT fusion, and NUT immunohistochemistry confirmed the diagnosis of NC. Subsequently, left pneumonectomy and lymph node dissection were performed, and the patient received pemetrexed and lobaplatin treatment. NGS technology played an important role in NC diagnosis in this case, and it may have clinical use for rare cancer diagnosis and guidance of potential targeted therapies. [ABSTRACT FROM AUTHOR]

To study the expressions and clinical significance of uPA and V-ATPase mRNA in human hepatocellular carcinoma. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the expressions of uPA and V-ATPase mRNA in 45 specimens of hepatocellular carcinoma (HCC), their para-neoplastic tissues and 7 parahepatic hemangioma tissues for controls. The diagnosis for all specimens was made by pathologists. The positive rates of uPA mRNA in HCC, para-neoplastic tissues and the controls were 100%, 86.44% and 28.57% respectively, and there were significant differences among three groups ( P < 0.05). The positive rates of V-ATPase mRNA in HCC, para-neoplastic tissues and the controls were 100%, 86.67% and 57.14% respectively, and there were also significant differences among three groups ( P < 0.05). In addition, the positive rates of uPA and V-ATP mRNA in HCC were significantly correlated with portal vein cancer thrombosis and remote metastasis ( P < 0.01). However, the positive rates had no correlation to cancer size or pathological stage, serum AFP lever and HBV infection ( P > 0.05). The high expressions of uPA and V-ATPase mRNA in HCC might be related to its growth, invasion and metastasis. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the association of Glutathione S-transferase (GST) M1 and T1 genetic polymorphisms and susceptibility to nasopharyngeal carcinoma (NPC) in a high risk area of Guangxi Zhuang Autonomous Region (province), Southwest of China. Methods: A case-control study was conducted to investigate the genetic polymorphisms of these enzymes (GSTM1 and GSTT1 null genotypes). A total of 127 NPC cases and 207 controls were recruited. Results: GSTM1 and GSTT1 null genotype frequencies were higher among NPC patients at a level of statistical significance (P<0.005; P<0.001 respectively), and both GSTM1 and GSTT1 null genotype were even more significant (P<0.001). Conclusion: NPC is the most common cancer in Guangxi. GST enzymes are involved in the detoxification of many environmental carcinogens. Homozygous deletions of GSTM1 and GSTT1 have been associated with several types of cancer. The risk to develop NPC has been associated with environmental factors such as cigarette smoking and EB virus infection. The present results indicate that the GSTM1 and GSTT1 deletion polymorphisms are associated with an increase risk of susceptibility to NPC, and both detoxific enzyme genes deletion is more important than a single gene deletion for the susceptibility to NPC. [ABSTRACT FROM AUTHOR]