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101.
Prostaglandin E2 (PGE2) is an important biological mediator involved in the defense against Mycobacterium tuberculosis (Mtb) infection. Currently, there are no reports on the mycobacterial components that regulate PGE2 production. Previously, we have reported that RpfE-treated dendritic cells (DCs) effectively expanded the Th1 and Th17 cell responses simultaneously; however, the mechanism underlying Th1 and Th17 cell differentiation is unclear. Here, we show that PGE2 produced by RpfE-activated DCs via the MAPK and cyclooxygenase 2 signaling pathways induces Th1 and Th17 cell responses mainly via the EP4 receptor. Furthermore, mice administered intranasally with PGE2 displayed RpfE-induced antigen-specific Th1 and Th17 responses with a significant reduction in bacterial load in the lungs. Furthermore, the addition of optimal PGE2 amount to IL-2-IL-6-IL-23p19-IL-1β was essential for promoting differentiation into Th1/Th17 cells with strong bactericidal activity. These results suggest that RpfE-matured DCs produce PGE2 that induces Th1 and Th17 cell differentiation with potent anti-mycobacterial activity.  相似文献   
102.
Full-scale fire tests were conducted by the United States Coast Guard to identify the fire extinguishing capabilities and limitations of Aerosol Extinguishing Systems (AES) in shipboard machinery space applications. A total of 18 tests were conducted in this evaluation utilizing the equipment from three AES manufacturers (Ansul, FirePro, and Flame Guard). The systems were tested against the current International Maritime Organization’s (IMO) test protocol (MSC/Circ. 1007) for approving AES for machinery space applications. All three systems exhibited good capabilities against Class B fires but had difficulty extinguishing the Class A fires. As a result of these limited capabilities against Class A fires, none of the three systems successfully met the requirements of the IMO test protocol (as currently written). The conditions in the space produced by the discharge of the systems were also quantified during these tests (visibility, temperature, particle densities, and gas concentrations). Based on the results of these tests, a number of modifications to the procedures, instrumentation, and fire scenarios in the test protocol were recommended.  相似文献   
103.
Recently, simulations based on the Monte Carlo code have been increasingly applied for physics phenomena, patient dose and quality assurance of radiation systems. The objective of this study was to use Monte Carlo simulation and measurement to verify dose and dose reduction in cephalography. The collimator was constructed with 3-mm thick lead plate, and attached to the tube head to remove regions of disinterest in the radiation field. A digital phantom patient was constructed to evaluate patient dose. In addition, detectors of pixel size 1×1 cm2 and 0.1×0.1 cm2 were constructed to check collimator location. The effective dose according to International Commission on Radiological Protection 103 was calculated with and without collimation. The effective doses for simulation with and without collimation were 5.09 and 11.32 μSv, respectively. The results of the calculated effective dose show 61.7 % reduction of field area and 55 % of effective dose. The Monte Carlo simulation is a good evaluation tool for patient dose.  相似文献   
104.
Electrohydrodynamic (EHD) jet printing is a technique using electric fields to eject inks through nozzle apertures. EHD jet printing is very attractive due to its non-contacting nature and compatibility with diverse materials and substrates. In this research, we have fabricated micron-sized dot arrays and line patterns with carbon black ink on Si wafer substrates using EHD jet printing. The effect of operating conditions such as applied voltage, working distance and stage speed on the size and shape of the jetted patterns and jetting cycles is investigated by using optical microscope, high speed camera and atomic force microscopy (AFM). We have also demonstrated the drop-on-demand feature of the EHD jet printing system by patterning carbon black ink lines with various widths and dot arrays with desired diameters and spacing by controlling the operating conditions.  相似文献   
105.
Organic semiconducting polymer thin-films of 3-hexylthiophene, 3-octylthiophene, 3-decylthiophene, containing highly oriented crystal were fabricated by gas-phase polymerization using the CVD technique. These poly(3-alkylthiophene) films had a crystallinity up to 80%, and possessed a Hall mobility up to 10 cm2/Vs. The degree of crystalinity and the mobility values increased as the alkyl chain length increased. The crystal structure of the polymers was composed of stacked layers constructed by a side-by-side arrangement of alkyl chains and in-plane pi-pi stacking. These thin films are capable of being applied to organic electronics as the active materials used in thin-film transistors and organic photovoltaic cells.  相似文献   
106.
International Journal on Software Tools for Technology Transfer - Declarative process modeling formalisms—which capture high-level process constraints—have seen growing interest,...  相似文献   
107.
Journal of Materials Science: Materials in Electronics - Conventional soldering methods with Pb-containing and Pb-free solder alloys have been extensively used in the manufacturing of the power...  相似文献   
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The net-shaping capability in spark plasma sintering (SPS) of ultrahigh-temperature ceramics has been explored in this study. The annular or ring-like shape is considered here as the first step to a more complex geometry compared to a solid cylinder or disk. ZrC powders have been SPS processed in specially designed graphite tooling to achieve the annular shape geometry. Experimental runs have been carried out to determine the optimal processing parameters for producing highly dense ZrC specimens in this geometry. Finite-element modeling framework has been constructed to determine the internal stress evolution, as well as densification, during the SPS of the annular-shaped ZrC. The formulated processing schemes for ZrC have been adapted to process SiC/ZrB2 composite powder with the purpose of making tooling components for SPS applications. The applicability of the obtained composite SPS tooling has been evaluated at high temperature and high pressure associated with SPS regimes.  相似文献   
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