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51.
Low temperature benzene oxidation in the presence of ozone on MnOx/MCM-41 catalysts has been studied. MnOx/MCM-41 catalysts were prepared from two different precursors, Mn(NO3)2 and Mn(CH3COO)2, and these samples were characterized by N2 sorption, X-ray diffraction, X-ray photoelectron spectroscopy and temperature programmed reduction. The characterization results showed that the MnOx/MCM-41 prepared from Mn(CH3COO)2 had higher oxygen mobility and dispersion than the MnOx/MCM-41 from Mn(NO3)2. As a result, the MnOx/MCM-41 obtained from Mn(CH3COO)2 showed higher catalytic activity for the oxidation of benzene using ozone; however, without ozone, the catalytic activity was negligible.  相似文献   
52.
Food Science and Biotechnology - It has been recently reported that the immune system has been linked to the nervous system. This study was conducted to investigate the effect of administration of...  相似文献   
53.
Tissue‐engineered scaffolds require an adequate three‐dimensional (3‐D) structure for cell growth and attachment. Solid freeform fabrication can provide the interconnected pore to induce the cell ingrowth, and electrospinning technique can make the nanofiber web with high surface for cell attachment. In this study, 3‐D polycaprolactone (PCL) scaffolds were fabricated using a rapid prototyping plotting system coupled with an electrospinning apparatus. Scanning electron micrographs showed that these hybrid scaffolds had a regular microfiber structure with interconnected pores and a nanofiber distribution appropriate for cell attachment. Scaffolds were seeded with MG63 cells for in vitro study and implanted in the tibia of rabbit for in vivo study. The resulting structure also facilitated cell adhesion, proliferation, and differentiation as evidenced by biochemical analyses and confocal microscopy. The hybrid scaffolds also exhibited good biocompatibility and osteoconductivity in animal studies. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers  相似文献   
54.
The preparation and physicochemical characteristics of sweetpotato flour with increased slowly digestible starch (SDS) fraction were investigated under various heat-moisture treatment (HMT) conditions. The optimum conditions for preparing slowly digestible sweetpotato flour established using response surface methodology were moisture content of 22%, temperature of 103°C, and treatment time of 5.8 h. The highest SDS content in heat-moisture treated sweetpotato flour was 57.6%. The relative crystallinity of heat-moisture treated sweetpotato flour decreased, but the X-ray diffraction pattern maintained the A-type. The DSC of the heatmoisture treated flour showed a decreased gelatinization temperature range and gelatinization enthalpy compared with native one. The viscosity profiles and values changed significantly with HMT, resulting in a higher pasting temperature, decrease of the viscosity values, and no breakdown. It indicates that heat-moisture treated sweetpotato flour is more stable at high temperatures and shear rates than native one.  相似文献   
55.
Small-cell lung cancer (SCLC) is the most aggressive form of lung cancer and the leading cause of global cancer-related mortality. Despite the earlier identification of membrane-proximal cleavage of cell adhesion molecule 1 (CADM1) in cancers, the role of the membrane-bound fragment of CAMD1 (MF-CADM1) is yet to be clearly identified. In this study, we first isolated MF-CADM1-specific fully human single-chain variable fragments (scFvs) from the human synthetic scFv antibody library using the phage display technology. Following the selected scFv conversion to human immunoglobulin G1 (IgG1) scFv-Fc antibodies (K103.1–4), multiple characterization studies, including antibody cross-species reactivity, purity, production yield, and binding affinity, were verified. Finally, via intensive in vitro efficacy and toxicity evaluation studies, we identified K103.3 as a lead antibody that potently promotes the death of human SCLC cell lines, including NCI-H69, NCI-H146, and NCI-H187, by activated Jurkat T cells without severe endothelial toxicity. Taken together, these findings suggest that antibody-based targeting of MF-CADM1 may be an effective strategy to potentiate T cell-mediated SCLC death, and MF-CADM1 may be a novel potential therapeutic target in SCLC for antibody therapy.  相似文献   
56.
Abstract

Low-cost optical particle counters (OPC) have gained increasing attention in recent years in exposure studies. Previous studies reported that the OPCs’ performance varies considerably with type of particles being measured; however, little information on their performance in monitoring common indoor aerosols is available. Given the significance of exposure to indoor aerosols and their associated adverse health effects, this experimental study investigates the performance of low-cost OPCs in monitoring individual aerosols that are commonly found indoors in a controlled chamber environment. Performances of four low-cost OPCs were examined under exposure to varying concentrations of biological (dust mite, pollen, cat, and dog fur) and non-biological (monodisperse silica and melamine resin) aerosols. Each particle sample was dispersed into the chamber using a computer-controlled syringe injection system, while size-resolved particle number concentrations were simultaneously measured by four low-cost OPCs (OPC N2, IC Sentinel, Speck, and Dylos) as well as a lab-grade reference sensor (AeroTrak). The study results showed measurable effects of particle size, particle type, and concentration on the low-cost OPC responses. Particle concentration had the most dominant effect on the linearity of low-cost sensors. Results also revealed that the sensor responses to four biological particles follow a similar pattern and converge to a linear line as the number concentration increases above 5?cm?3. As for non-biological particles, the OPC responses were more varied depending on the particle type and size, especially in the concentration range <10?cm?3. Calibration equations developed in this study provide baseline information for correcting low-cost OPC readings when utilized to measure concentrations of individual indoor aerosol sources.

Copyright © 2019 American Association for Aerosol Research  相似文献   
57.
58.
The existence of curve veering phenomenon is investigated in outer-clamped annular plates subject to in-plane force. The perturbation and Galerkin's methods are employed to verify the existence qualitatively and quantitatively, respectively. From qualitative and quantitative analyses, it is found that the curve veering phenomenon may take place in outer-clamped annular plates under nonuniform in-plane force.  相似文献   
59.
Novel zero-voltage-transition PWM multiphase converters   总被引:3,自引:0,他引:3  
Novel zero-voltage-transition (ZVT) pulse-width-modulation (PWM) multiphase converters are presented. To construct a ZVT multiphase converter in a conventional way, it is necessary to add the auxiliary circuits with as many number of phases. In the proposed converter, only one auxiliary circuit provides the zero-voltage switching (ZVS) for main switches and diodes of all phases. So, the new converters are cost effective and attractive for high-performance and high power-density conversion applications. Operation, features, and characteristics of the two-phase buck converter are illustrated and verified on a 4-kW 100-kHz insulated gate bipolar transistor (IGBT)-based (a MOSFET for the auxiliary switch) experimental circuit  相似文献   
60.
Montesquieu argued that residents of warmer climates are more emotionally expressive than those living in cooler ones. More than 2,900 college students from 26 countries completed a brief questionnaire assessing the degree to which they considered Northerners and Southerners within their own countries to be emotionally expressive. In addition, individuals rated themselves on their own degree of expressiveness. In partial confirmation of Montesquieu's hypothesis, it was found that large within-country North-South stereotypes exist. Especially in Old World countries, Northerners are viewed as less emotionally expressive than Southerners. Regression and other analyses revealed that self-ratings of expressiveness were, in fact, related to being from the South and to warmer mean temperatures. Several possible explanations for these effects are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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