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  • Author: Qun Zheng x
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Abstract

Backgroud: The high postoperative recurrence of hepatocellular carcinoma (HCC) is a problem that would benefit from the identification of indicators of recurrence and prognosis. In the past few years, research has shown that E-cadherin and CD34 can be used as indicators of the invasion of malignant tumors. In the present study, we investigated the expression of E-cadherin and CD34 in HCC patients.

Methods: Expression levels of E-cadherin and CD34 in 41 HCC samples were detected using two-step immunohistochemical methods and compared with clinical pathological parameters and survival rate.

Results: The positive rates of E-cadherin and CD34 expression in 41 HCC cases were 48.78% and 100%, respectively. Expression of E-cadherin was significantly lower in patients with larger tumors, a high risk invasion and Edmondson classification III or IV (p<0.05). There was a significant relationship between CD34 expression and age and tumor invasiveness (p<0.05). There was no significant relationship between expression of CD34 and E-cadherin by Spearman statistical analysis (p>0.05). The survival rate in patients with negative expression of E-cadherin was significantly lower.

Conclusions: The expression of CD34 cannot be used singly as a prognostic indicator for HCC patients. The co-expression of E-cadherin and CD34 cannot be used as a prognostic indicator for HCC patients.

Clin Chem Lab Med 2008;46:1122–6.

Abstract

Boron-doped BaTiO3 precurors (BaTi1−xB2xO3+X) were prepared via the glycol-glycerol complexes of boron, titanium (IV), and barium. With optimum composition, ceramics with dielectric properties comparable to those of pristine BaTiO3 ceramic sintered at 1300°C can be obtained after sintered at temperature less than 900°C (room-temperature dielectric constant ∼4000, dielectric strength ∼7.0 kV/mm). The appreciable decrease in sintering temperature is attributable to (a) addition of boron dopant as substitute of titamium rather than to stochiometric BaTiO3, and (b) application of glycol-glycerol solvents/ligands in the synthesis of precursors, which guarantees the compositional homogenization of the final ceramics.

Abstract

The mechanical, electronic, and optical properties of β-B6O are calculated by first-principles. The structural optimization and all properties are calculated by the method of generalized gradient approximation – Perdew, Burke and Ernzerhof (PBE). The hardness of β-B6O is 39 GPa under a pressure of 0 GPa, which indicates that it belongs to a hard material. The band gap is indirect with a value of 1.836 eV, showing that β-B6O is a semiconductor. The research of the electron localization function shows that the bonds of β-B6O are covalent bonds, which can increase the stability of the compound. The phonon dispersion curves present the dynamical stability of β-B6O under pressures of 0 and 50 GPa. The optical properties of β-B6O are also calculated. In the energy range from 0 to 18 eV, β-B6O presents high reflectivity; it has a strong absorption in the energy range from 3 to 18 eV. The refractive index results show that light propagates through the β-B6O in a difficult manner in the energy range from 6.9 to 16.5 eV. In addition, the energy of the plasma frequency for β-B6O is 16.6 eV and the peak value of the loss function is 13.6. These properties provide the basis for the development and application of β-B6O.

Abstract

The following paper presents dynamic leakage rate and coupled interaction for variable speed rotor-labyrinth (LABY) seal, with rotating speed from 18 to 30 krpm. Variable speed rotor vibration characteristics are incorporated into transient computational fluid dynamic (CFD) calculations as boundary conditions of seal flow field to show the real-time effect of rotordynamic in seal flow field. Leakage rate across a variable speed rotor-seal increases with rotor vibration, but this effect is prominent at lower speed than at higher speed. Leakage characteristic is determined by differences in rotor vibration amplitude rather than rotating speed. The results also reveal that aerodynamic forces of labyrinth seal flow field can improve rotor stability, and this interaction between rotor and seal decreases with the increase of rotating speed.

Abstract

Transition-metal dichalcogenides (TMDCs) and black phosphorus (BP) are typical 2D materials with layer-dependent bandgaps, which are emerging as promising saturable absorption materials for pulsed fiber lasers. In this review, we discuss the nonlinear saturable absorption properties of TMDCs and BP, and summarize the recent progress of saturable absorbers from fabrication methods to incorporation strategies. The performances of saturable absorbers and the properties of Q-switched/mode-locked fiber lasers at different wavelengths are summarized and compared to give a comprehensive insight to optical modulators based on TMDCs/BP, and to promote their practical applications in nonlinear optics.

Using an extended mapping approach, a new type of variable separation excitation with two arbitrary functions of the (2+1)-dimensional Broer-Kaup-Kupershmidt system (BKK) is derived. Based on this excitation, abundant propagating and non-propagating solitons, such as dromions, rings, peakons, compactons, etc. are found by selecting appropriate functions. - PACS: 05.45.Yv, 03.65.Ge

Abstract

The onset of spike stall induced by the interaction of hub corner separation flow with the tip leakage flow is investigated in detail by numerical method in this paper. The time resolved results indicate that the remarkable radial secondary flow from hub to tip near the trailing edge is formed when the compressor approaching rotating stall. The radial secondary flow is unstable and cross-passages propagates, which flows in and away out of the tip region periodically. The disturbance caused by radial secondary flow will influence the tip leakage flow directly by reforming the vortexes in blade tip region. A secondary vortex which comes from the radial migration of corner separation and is induced by the tip leakage vortex appears in the tip region. The simulation result demonstrates that the generation of the secondary vortex is an important symbol of blockage growth in the tip region at the stall inception phase. The disturbance produced by secondary vortex is an incentive of the leading edge overflow and the intensity of secondary vortex could be used as a criterion of rotating stall before leading edge spillage.

Abstract

Background: Diabetic cardiomyopathy is an important complication of type 2 diabetics. The role of immunoinflammation, immunity, and diet has not been adequately clarified.

Objective: We investigated the relationships between diabetic cardiomyopathy and immuno-inflammation, as well as immunity and diets.

Methods: Sixty Sprague-Dawley (SD) male rats were included in this study, from which 12 were randomly selected as the normal control group (group A) and of which the remaining 48 were considered as the type 2 diabetes mellitus (T2DM) model group. Group A was fed with common diets and the T2DM model group, with high-glucose diets (by adding 20% cane sugar, 10% lard, and 2.5% cholesterol into a 67.5% common diet). After 4-week feeding, the T2DM model group was randomly allocated into three groups according to the diet, highfat diet group (group B), common diet group (group C), and low-fat diet group (group D). All the three groups were then fed for another 10 weeks. At the end of the experiment, body weight, random blood glucose levels, and cardiac weight were measured. Left ventricular tissue was obtained for light microscopy and electron microscopy. Deposits of immunoglobulin G (IgG) in myocardium were identified by immunohistochemistry. Serum levels of high-sensitivity C-reactive protein (hs-CRP) were determined using the enzyme-linked immunosorbent assay (ELISA). All data were statistically analyzed.

Results: The serum level of hs-CRP was significantly higher in groups B, C, and D, than in the control group. Therefore, IgG deposits among cardiac muscle cells were observed in all the model groups, significant deviations were noted in group A (p <0.01) and IgG deposits were less in group D than in groups B and C (p <0.01).

Conclusion: Immuno-inflammation participates in the development of T2DM and diabetic cardimyopathy. Immune injury can be alleviated following dietary interference.