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This paper is devoted to establishing the global regularity involving magnetic fields and partial components of the velocity for the 3D generalized magnetohydrodynamic equations with dissipation terms −(−Δ)αu and −(−Δ)βb. We assume 1≤α=β≤32 and prove that if b,u3∈Lw(0,T;Lq(R3)) with 2αw+3q≤3(2α−1)4+3(1−ϵ)4q, 3+ϵ2α−1

The Riemann problem for a Chaplygin magnetogasdynamics system of compressible fluid flow with a triple parameter perturbation containing flux, pressure, and magnetic field is first solved. Second, it is shown that as the triple parameter flux perturbation, pressure, and magnetic field vanish, any Riemann solution containing two shock waves tends to a delta-shock solution to the transport equations and any Riemann solution containing two rarefaction waves tends to a vacuum solution to the transport equations. Third, it is also proved that as the double parameter flux perturbation and magnetic field vanish, any Riemann solution containing two shock waves approaches a delta-shock solution to the Chaplygin gas equations and any Riemann solution containing two rarefaction waves tends to a solution containing two contact discontinuities of the Chaplygin gas equations. Finally, some numerical results are presented to be consistent with the theoretical analysis.

Grape seed proanthocyanidin (GSPA) consists of catechin, epicatechin and epicatechin gallate, which are strong antioxidants that are beneficial to health and may attenuate or prevent Alzheimer's disease (AD). In the present study, the effects of GSPA on pheochromocytoma (PC12) cell viability were determined using cell counting kit-8 and lactate dehydrogenase (LDH) assays, whereas apoptosis and mitochondrial membrane potential (Ψm) were measured via flow cytometry analysis. The effect of GSPA administration on the behavior and memory of amyloid precursor protein (APP)/presenilin-1 (PS-1) double transgenic mice was assessed using a Morris water maze. APP Aβ peptides and tau hyperphosphorylation were examined by western blotting; whereas the expression levels of PS-1 were evaluated by reverse transcription-quantitative polymerase chain reaction and compared with pathological sections stained with hematoxylin-eosin and Congo red. Data from the in vitro experiments demonstrated that GSPA significantly alleviated Aβ25-35 cytotoxicity and LDH leakage ratio, inhibited apoptosis and increased Ψm. The findings from the in vivo experiments showed a significant enhancement in cognition and spatial memory ability, an improvement in the pathology of APP and tau protein and a decrease in PS-1 mRNA expression levels. Therefore, the results of the present study indicated that GSPA may be a novel therapeutic strategy for the treatment of AD or may, at the very least, improve the quality of life of patients with AD.

An unusual phenomenon of strain induced martensite stabilization in the β-type Ti-30Zr-10Nb shape memory alloy was studied. The strain induced α″-martensite formed in the β phase during the tensile loading on the metastable Ti-30Zr-10Nb alloy. It was stabilized at room temperature and thus no superelastic recovery occurs in the alloy upon unloading. The reverse transformation temperature of the strain induced α″-martensite increased from 333 K to 369 K with increasing pre-strain from 2% to 8%. Shape memory recovery occurred in the pre-strianed Ti-30Zr-10Nb alloy upon heating. The maximum shape memory effect of the alloy was 3.5% with the pre-strain of 8%.

Sediment and pore water samples have been collected from the coastal tidal flat in the Shuangtaizi estuary, China, in order to investigate the geochemical behavior of iron, cadmium, and lead during diagenesis and to assess the degree of contamination. The calculated enrichment factors and geoaccumulation indices for separate elements show that anthropogenic activities have had no significant influence on the distribution of Fe and Pb in the study area, whereas the distribution of Cd has been closely influenced in this way. The high percentage of exchangeable Cd (average of 56.34%) suggests that Cd represents a potential hazard to benthic organisms in the estuary. The calculated diffusive fluxes of metals show that the most mobilized metal is Fe (9.22 mg m−2 a−1), followed by Cd (0.54 mg m−2 a−1) and Pb (0.42 mg m−2 a−1). Low Fe2+ contents in surface pore water, alongside high chromium-reducible sulfur contents, and low acid-volatile sulfur, and elemental sulfur contents at 0–25 cm depth in sediments show that Fe2+ is formed by the reduction of Fe oxides and is transformed first to a solid phase of iron monosulfides (FeS) and eventually to pyrite (FeS2). The release of adsorbed Pb due to reductive dissolution of Fe/Mn oxides during early diagenesis could be a source of Pb2+ in pore water. From the relatively low total organic carbon contents measured in sediments (0.46–1.28%, with an average of 0.94%) and the vertical variation of Cd2+ in pore water, sulfide or Fe/Mn oxides (instead of organic matter) are presumed to exert a significant influence on carrying or releasing Cd by the sediments.

Grape seed proanthocyanidin (GSPA) consists of catechin, epicatechin and epicatechin gallate, which are strong antioxidants that are beneficial to health and may attenuate or prevent Alzheimer's disease (AD). In the present study, the effects of GSPA on pheochromocytoma (PC12) cell viability were determined using cell counting kit-8 and lactate dehydrogenase (LDH) assays, whereas apoptosis and mitochondrial membrane potential (Ψm) were measured via flow cytometry analysis. The effect of GSPA administration on the behavior and memory of amyloid precursor protein (APP)/presenilin-1 (PS-1) double transgenic mice was assessed using a Morris water maze. APP Aβ peptides and tau hyperphosphorylation were examined by western blotting; whereas the expression levels of PS-1 were evaluated by reverse transcription-quantitative polymerase chain reaction and compared with pathological sections stained with hematoxylin-eosin and Congo red. Data from the in vitro experiments demonstrated that GSPA significantly alleviated Aβ25–35 cytotoxicity and LDH leakage ratio, inhibited apoptosis and increased Ψm. The findings from the in vivo experiments showed a significant enhancement in cognition and spatial memory ability, an improvement in the pathology of APP and tau protein and a decrease in PS-1 mRNA expression levels. Therefore, the results of the present study indicated that GSPA may be a novel therapeutic strategy for the treatment of AD or may, at the very least, improve the quality of life of patients with AD.

The yeast Pichia pastoris GS115 is a widely used microbial cell factory for the production of heterologous protein. In order to reveal the impacts of high heterologous protein expression on the central metabolism of Pichia pastoris GS115 using glucose as sole carbon source, we engineered a high β-galactosidase expression strain P. pastoris G1HL and a low expression control strain P. pastoris GHL through controlling the initiation strength of constitutive promoter pGAP. The carbon flux distributions in these two strains were quantified via (13)C metabolic flux analysis. Compared to the control strain, G1HL showed a lower growth rate, a higher flux through glycolysis pathway, a higher flux through pentose phosphate pathway, and a lower flux through by-products secretion pathway. The metabolic flux redistribution in G1HL was thought to compensate the increased redox cofactors and energy demands caused by the high protein expression. Although the fluxes through Krebs cycle in two engineered strains were almost the same, they were significantly lower than those in wild strain. The enhanced expression of β-galactosidase by glutamate supplementation demonstrated the potential of P. pastoris GS115 to catabolize more carbon through the Krebs cycle for even higher protein expression. In conclusion, our work indicates that P. pastoris GS115 can readjusts the central metabolism for higher heterologous protein expression and provides strategies for strain development or process optimization for enhancing production of heterologous protein.

The pulsed liquid fluidized bed was studied using numerical simulation and experimental methods, The area-averaged two-fluid model (TFM) was used to simulate the pulsed fluidization. The bed expansion and collapse processes were simulated first and the phenomena obtained from the calculation were consistent with our previous experiments and observations. In the pulsed fluidization, the variation of bed height, the variations of particle velocity and concentration distribution were obtained and analyzed. Experiments were carried out to validate the simulation results. The pressure variation with time at different locations was measured using pressure transducers and compared with the simulated results. The variations of bed height and particle concentration distribution were recorded using a digital video camera recorder. The results were consistent with the simulation results as a whole.

A new method to study collapsing process of fluidized bed was proposed. The method is based on the analysis of the pressure variation during collapse. A model is proposed to describe the pressure variation on any location of the bed during collapse. Three kind of particles were fluidized by air and the pressure variation after shutting down the gas supply was measured by pressure transducers and simulated by the proposed model. The simulated results were in good agreement with the experimental data. The parameters of the fluidized bed, such as bubble fraction alpha(b), particle fraction in dense phase alpha(p), bubble velocity u(b) and slip velocity of particle u(i), can be estimated from the measured pressure data by using the proposed model. The model was also used to calculate the pressure variation in pulsed fluidized beds with low frequency.