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991.
CoRuPt and CoPtRu catalysts were prepared on carbon paper (CP) using various electrochemical processes including Sn sensitization, Pd activation, Co electrodeposition and galvanic displacement. The Sn-Pd process is a surface treatment that guarantees a larger number of nucleation sites on CP for subsequent Co electrodeposition by modifying the surface to be more hydrophilic. Co particles were deposited on Sn-Pd-treated CP (SCP) by controlling deposition potential and time. Then, Pt and Ru galvanic displacements were performed on the Co particles to form CoRuPt/SCP and CoPtRu/SCP catalysts. Electrochemical measurements confirmed that the CoRuPt/SCP - 1 catalyst with a 1.02 Pt/Ru surface molar ratio showed a peak potential of 741 mV (vs. NHE) for methanol oxidation and 637 mV for carbon monoxide stripping. These values were 80 and 8 mV lower, respectively, than those of a PtRu/C commercial catalyst.  相似文献   
992.
Coptidis Rhizoma is the dried rhizome from the Coptis chinensis Franch. that has been shown to have a number of beneficial pharmacological properties including antioxidant, anti-inflammatory, and anti-cancer effects. However, the anti-cancer effects of Coptidis Rhizoma on hepatocellular carcinoma (HCC) remain unclear. In this study, we investigated the anti-cancer properties of Coptidis Rhizoma ethanol extract (CR) in HCC Hep3B cells and in a xenograft mouse model. Our results showed that the CR significantly inhibited cell growth and induced apoptosis in Hep3B cells through increased expression of Bcl-2 associated x-protein (Bax) and cleavage of poly-ADP ribose polymerase (PARP), reduced expression of Bcl-2, and activated caspases. CR also increased the generation of intracellular reactive oxygen species (ROS), which caused a loss of mitochondrial membrane potential (MMP, ΔΨm) and activation of the mitochondria-mediated intrinsic apoptosis pathway. Moreover, N-acetylcysteine (NAC), a ROS inhibitor, markedly blocked the effects of CR on apoptotic pathways. CR also induced the expression of light chain 3 (LC3)-I/II, a key autophagy regulator, whereas CR-mediated autophagy was significantly suppressed by NAC. In addition, pre-treatment with NAC perfectly attenuated the inhibition of cell invasion and migration of CR-stimulated Hep3B cells. Furthermore, oral administration of CR suppressed Hep3B tumor growth in xenograft mice without toxicity, alterations to body weight, or changes in hematological and biochemical profiles. Taken together, our findings suggest that CR has anti-tumor effects that result from ROS generation, and may be a potential pharmacological intervention for HCC.  相似文献   
993.
994.
Enterococcus spp. from powdered infant formula and follow-on formulas were identified and characterized for antibiotic susceptibility to confirm the enterococcal safety. Seventy-three Enterococcus from 96 powdered infant formulas and 26 strains from 33 follow-on formulas were isolated. More than 90% of Enterococcus in the foods were E. faecium. E. casseliflavus, and E. faecalis were also isolated. All Enterococcus were sensitive to ampicillin, penicillin, tetracycline, and vancomycin. However, 2 E. casseliflavus showed low resistance to vacomycin by minimum inhibitory concentration 4.0 μg/mL. Multiplex PCR indicated no existence of highly hazardous vancomycinresistant vanA and vanB genes. The isolates also showed the broad susceptibilities to erythromycin, ripampin, and streptomycin. Major strains of about 60% were intermediately and highly resistant to erythromycin and streptomycin, respectively. However, Enterococcus resistances to those antibiotics were not high and similar to those of Enterococcus from the other evaluated foods. Therefore, it appeared that powdered infant formula and follow-on formula might be safe to Enterococcus with regard to vancomycin and the antibiotics.  相似文献   
995.
The morphologies of inkjet-printed narrow silver lines on fluorocarbon film-coated glass substrates were measured with varying contact angles and drop spacing to study the actual stability of line printing by using a practical inkjet system. From a practical stability point of view, three types of the lines were observed: stable, unstable, and meta-stable. The stable lines were free from any bulging or breaking; the unstable lines had repetitive and periodic instabilities; and the meta-stable lines had no repetitive instability but had irregular bulges that appear sparsely. Unstable line printing resulted from either the dynamic or static instability of bead flow, which arose when the pressure-driven bead flow was too large or too small compared with droplet deposition rate, respectively. Whether the printing would be stable or meta-stable was determined by the anti-bulging stability of the flow against other disturbances. The anti-bulging stability increased when the bead flow rate was balanced with the printing rate, whereas it decreased for the present system when the flow-balance became sensitive to drop spacing.  相似文献   
996.
Multimedia Tools and Applications - Robust object recognition has drawn increasing attention in the field of computer vision and machine learning with fast development in feature extraction and...  相似文献   
997.
Systemic lupus erythematosus (SLE) is an immune-complex-mediated multi-systemic autoimmune condition of multifactorial etiology, which mainly affects young women. It is currently believed that the onset of SLE and lupus flares are triggered by various environmental factors in genetically susceptible individuals. Various environmental agents and toxicants, such as cigarette smoke, alcohol, occupationally- and non-occupationally-related chemicals, ultraviolet light, infections, sex hormones and certain medications and vaccines, have been implicated to induce SLE onset or flares in a number case series, case-control and population-based cohort studies and very few randomized controlled trials. Here, we will describe some of these recognized environmental lupus triggering and perpetuating factors and explain how these factors potentially bias the immune system towards autoimmunity through their interactions with genetic and epigenetic alterations. Further in-depth exploration of how potentially important environmental factors mechanistically interact with the immune system and the genome, which trigger the onset of SLE and lupus flares, will certainly be one of the plausible steps to prevent the onset and to decelerate the progress of the disease.  相似文献   
998.
999.
This study deals with parametric effects on bucking behaviors of laminated composite structures containing an embedded rectangular delamination using the enhanced assumed strain (EAS) three-dimensional element. The three-dimensional finite element (FE) formulation based on the EAS method for composite structures shows excellence from the standpoints of computational efficiency, especially for distorted element shapes. Using the EAS FE formulation developed for this study, the effects of embedded delamination sizes and ply orientations on the elastic buckling behaviors for various aspect ratios and width-to-thickness ratios are studied. The numerical results obtained are in good agreement with those reported by other investigators. Furthermore, the new results reported in this paper show the progression of local buckling and its influence on global buckling and vice versa. Key observation points are discussed and a brief design guideline is given.  相似文献   
1000.
Ren H  Du C  Park K  Volkow ND  Pan Y 《Applied physics letters》2012,100(23):233702-2337024
We present particle counting ultrahigh-resolution optical Doppler tomography (pc-μODT) that enables accurate imaging of red blood cell velocities (ν(RBC)) of cerebrovascular networks by detecting the Doppler phase transients induced by the passage of a RBC through a capillary. We apply pc-μODT to image the response of capillary ν(RBC) to mild hypercapnia in mouse cortex. The results show that ν(RBC) in normocapnia (ν(N)?=?0.72?±?0.15?mm/s) increased 36.1%?±?5.3% (ν(H)?=?0.98?±?0.29?mm/s) in response to hypercapnia. Due to uncorrected angle effect and low hematocrit (e.g., ~10%), ν(RBC) directly measured by μODT were markedly underestimated (ν(N) ≈ 0.27?±?0.03?mm/s, ν(H) ≈ 0.37±?0.05?mm/s). Nevertheless, the measured ν(RBC) increase (35.3%) matched that (36.1%?±?5.3%) by pc-μODT.  相似文献   
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