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Transport phenomenon in porous media is essential in various scientific and engineering fields. The permeability and porosity of porous media serve important functions in transport phenomena. In this study, a complex model that considers the characters of pore microstructure and fluid in porous media is developed for the permeability and porosity of porous media. The flow rate expressions of this model are compared with those of previous models. As the proposed models relate the properties of fluids to the structural parameters of porous media, the various expressions of the developed model can reveal the phenomena of all types of fluid flow in a variety of porous media. The predicted permeabilities and porosities show good agreement with the available experimental data and illustrate that the proposed model can be used to characterize flow in porous media. [ABSTRACT FROM AUTHOR]

Abstract: Objective: This study aims to establish and evaluate the methodology of isolated rabbit eye (IRE) test. Methods: IRE test was performed according to modifications of the in vitro toxicology (INVITTOX) Protocol No.85: Rabbit enucleated eye test by European Centre for the Validation of Alternative Methods (ECVAM), and then 26 chemicals and 26 cosmetic products were tested in both in vitro IRE and in vivo Draize tests. A statistical analysis was conducted to determine the relevance of the IRE test to the data generated in the Draize test. Results: IRE test was established successfully in our laboratory. It was shown that ranking correlation and class concordance were fairly well between the IRE test and the Draize test for 26 reference chemicals (Fisher''s Exact Test χ2=51.314, P<0.001; McNemar P=0.261; Gamma=0.960, P<0.001; Kappa=0.843, P<0.001) and 26 cosmetic products (Fisher''s Exact Test χ2=15.522, P<0.001; McNemar P=0.311; Gamma=0.967, P<0.001; Kappa=0.611, P<0.001). Conclusion: IRE test was established successfully for in vitro testing of eye irritation as an alternative to Draize test. [Copyright &y& Elsevier]

Abstract: Background: Genetic variants of the genes encoding HIV-1 co-receptors and their ligands, CCR5-Δ32, CCR5m303A, CCR2-64I and SDF1-3′A, are implicated in the susceptibility to HIV-1 infection, and the prevalence of these mutations varies by ethnicity. However, little is known about their distribution in Uighurs. Objectives: This study aimed at characterizing the frequency of these HIV-related gene variants in a high-risk Uighur population. Study designs: A total of 251 HIV-1 seropositive and 238 seronegative high-risk Uighurs were recruited and their genotypes of CCR5-Δ32, CCR5m303A, CCR2-64I and SDF1-3′A were analyzed by PCR and PCR-ligase detection reaction (PCR-LDR). Results: The allelic frequency of CCR5-Δ32, CCR5m303A, CCR2-64I and SDF1-3′A was 4.40%, 2.66%, 25.66% and 57.36%, respectively, in this population. Apparently, the Uighur population has low frequency of CCR5-Δ32 and CCR5m303A, but high frequency of CCR2-64I and SDF1-3′A. While there was no significant difference in the frequency of CCR5-Δ32, CCR2-64I and SDF1-3′ A between HIV-1 seropositive and seronegative groups the frequency of CCR5m303A in HIV-1 seropositive group was significantly higher than that in seronegative group (P =0.006, OR=3.982 and 95%CI 1.514–10.476). Conclusions: Our data suggest that the CCR5-Δ32, CCR2-64I and SDF1-3′A variants may have limited effect on protecting from HIV-1 infection in Uighurs. Rather, the CCR5m303A may be associated with the risk for HIV-1 infection in high-risk Uighurs. [Copyright &y& Elsevier]

Highlights • A two-way momentum coupling model is built to simulate the droplet-laden flows in the moisture separators. • UDF code is developed to solve the two-way coupling model based on FLUENT. • The simulation values of separation efficiency and pressure drop of wave-type and swirl-vane separator are both simulated. Abstract Moisture separator is one of the crucial equipment of the pressurized water reactor (PWR) nuclear power plant. In the separators, droplets could be regarded as the dispersed phase in terms of the gas–liquid two-phase flow. In order to predict the pressure drop of the droplet-laden flows in a more reasonable way, a fully two-way momentum coupling model based on the Lagrangian-Eulerian methodology is established. Then, a skilled self-programming code is implemented into the commercial CFD software FLUENT by the interface called User Defined Function (UDF) to solve this two-way coupling model. In the model application part, we first perform the numerical investigation of three different kinds of wave-type separators. The magnitude of the modeling separation efficiency and the changing trend of the pressure drop are in good agreement with the experimental data. Second, the gas–liquid flow in a swirl-vane separator is simulated under different operation conditions. The maximum relative error of the pressure drop by the two-way coupling model is over two times less than the simulation results by the one-way coupling model. Hence, the results show that the two-way coupling model, as well as the UDF solving program, performs a more comprehensive approach for the modeling of the gas–liquid two-phase flows in the moisture separators. [ABSTRACT FROM AUTHOR]