[Standard analysis and implementation suggestions of "General Principles for Diagnosis of Occupational Radiation Diseases"].

The national standard "General Principles for the Diagnosis of Occupational Radiation Diseases" (GBZ112-2017) was issued and implemented to replace "General Principles for the Diagnosis of Occupational Radiation Diseases" (GBZ112-2002). In this paper, the significance of the new standard, the background of revision, the revision basis of important indicators and the matters needing attention in the application of the standard were interpretated in detail. Especially for the revision basis of important indicators, such as the determination of the basic principles of diagnosis, the diagnostic basis, the principle of dose evaluation and the principle of treatment are explained in detail, so as to avoid the possible misunderstandings and misgiving in the use of the standard.

The SNORA21 expression is upregulated and acts as a novel independent indicator in human gastric cancer prognosis.

OBJECTIVE: Emerging evidence indicates that small nucleolar RNAs (snoRNAs) act crucial roles in oncogenesis. Herein, the aim of this study is to investigate the clinical value of SNORA21 expression in gastric cancer (GC). PATIENTS AND METHODS: The expression of SNORA21 was determined in 79 cases of GC tissues and adjacent normal tissues by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) analysis. The association between SNORA21 expression and clinicopathological features was analyzed by the chi-square test. The survival curves were calculated by the Kaplan-Meier method and log-rank test. Univariate and multivariate analyses were used to assess the prognostic value of SNORA21 expression. RESULTS: Our results first demonstrated that SNORA21 expression was significantly upregulated in human GC tissues and cells compared to their corresponding adjacent normal tissues and GES-1 cells, respectively (p<0.05). Furthermore, elevated SNORA21 expression was significantly associated with distant metastasis (p<0.05) and lymph node metastasis (p<0.05) in GC patients. Kaplan-Meier survival plots demonstrated that higher SNORA21 expression was associated with poor disease-free survival (DFS) and overall survival (OS) rate, respectively. Univariate analysis and multivariate regression analysis indicated that a higher SNORA21 was an independent risk factor for prognosis in GC patients. CONCLUSIONS: The current results indicate that SNORA21 expression may be served as a predictor of GC prognosis.

Band-gap tunability and dynamical instability in strained monolayer and bilayer phosphorenes.

Very recently, field-effect transistors based on few-layer phosphorene crystals with a thickness of down to a few nanometres were successfully fabricated, triggering interest in this new functional two-dimensional material. In this work, we apply first-principles calculations to studying the evolution of electronic and phononic structures with out-of-plane strain for monolayer and bilayer phosphorenes. It is found that the vertical stress can be used to tune the band gap of a semiconducting phosphorene in a wide range. On the other hand, the vertical stress can make the phosphorene lattice become dynamically unstable and surface reconstruction or structural phase transition may occur. Due to the interlayer van der Waals coupling, the dynamically stable range of bilayer phosphorene under vertical stress is wider than that of monolayer phosphorene. It is proposed whether or not a semiconductor-semimetal transition occurring in a strained phosphorene is determined not only by its band gap closing, but also by its lattice stability against strain. This information is essential for the strain engineering of phosphorene and future device fabrication.

Erythrocyte hemodynamics in stenotic microvessels: a numerical investigation.

This paper presents a two-dimensional numerical investigation of deformation and motion of erythrocytes in stenotic microvessels using the immersed boundary-fictitious domain method. The erythrocytes were modeled as biconcave-shaped closed membranes filled with cytoplasm. We studied the biophysical characteristics of human erythrocytes traversing constricted microchannels with the narrowest cross-sectional diameter as small as 3 µm. The effects of essential parameters, namely, stenosis severity, shape of the erythrocytes, and erythrocyte membrane stiffness, were simulated and analyzed in this study. Moreover, simulations were performed to discuss conditions associated with the shape transitions of the cells along with the relative effects of radial position and initial orientation of erythrocytes, membrane stiffness, and plasma environments. The simulation results were compared with existing experiment findings whenever possible, and the physical insights obtained were discussed. The proposed model successfully simulated rheological behaviors of erythrocytes in microscale flow and thus is applicable to a large class of problems involving fluid flow with complex geometry and fluid-cell interactions. Our study would be helpful for further understanding of pathology of malaria and some other blood disorders.

Numerical simulation of rheology of red blood cell rouleaux in microchannels.

An elastic spring model is applied to simulate the skeletal structure of the red blood cell (RBC) membrane and to study the dynamical behaviors of the red blood cell rouleaux (aggregates) in microchannels. The biconcave shape of RBCs in static plasma and the tank-treading phenomenon of single RBCs in simple shear flows have been successfully captured using this model. The aggregation and dissociation of RBCs with different deformability have been investigated in both shear and Poiseuille flows by taking into consideration the rheology of the cells and the intercellular interaction kinetics. It is found that the equilibrium configuration of the rouleaux formed under no-flow condition, the motion of the rouleaux in the flows, and the rheological behavior of individual cells in the rouleaux is closely related to the intercellular interaction strength, hydrodynamic viscous forces, and the deformability of the cell membrane.