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101.
Inflammatory pseudotumor (inflammatory fibroid polyp) of the ileum is a rare, usually solitary and polypoid lesion that frequently presents clinically as small-intestinal intussusception and obstruction. Regional lymph nodes are usually not involved. We describe an inflammatory pseudotumor of the ileum that was multifocal, not polypoid, and involved one regional lymph node. Grossly, two circumferential transmural nodules were separated by 8.5 cm of normal ileum. Microscopically, the lesion extended through the muscularis propria into peri-intestinal adipose tissue and involved one noncontiguous regional lymph node. The pseudotumor was composed of highly vascularized stroma with a mixture of spindle cells and chronic inflammatory cells including numerous eosinophils, lymphocytes, plasma cells, histiocytes, neutrophils, and multinucleated giant cells forming small granulomas. Immunohistochemically, the majority of spindle cells reacted with vimentin but not smooth-muscle, endothelial, or lymphoid markers. Ultrastructurally, the spindle cells had abundant rough endoplasmic reticulum, cytoplasmic filaments, and dense bodies consistent with myofibroblasts, plump endothelial cells (some with Weibel-Palade bodies), and chronic inflammatory cells. We prefer the term inflammatory pseudotumor to inflammatory fibroid polyp for the lesion in this case, since it was not polypoid and shared many histologic features with inflammatory pseudotumors arising at sites other than the gastrointestinal tract.  相似文献   
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103.
Species, dose, and mean ion resident time (MIRT(c)) in the concentrate of electro-dialysis reversal (EDR) desalination are analysed. In the classical EDR, dimensions, flow, and velocity of dilute and concentrate are equal; Langelier saturation index (LSI) and CaSO4 saturation are used to control the scaling and fouling processes in concentrate, as such LSI < + 2.16 for preventing CaCO3 from fouling and CaSO4 saturation level < 200 for averting CaSO4 from precipitation. If LSI is more than allowable limit, acid is added in concentrate to keep CaCO3 continuously dissolving; if CaSO4 saturation level in concentrate is more than the allowable limit, sodium hexametaphosphate (SHMP) is added in concentrate to maintain CaSO4 dissolving. EDR, however, was successfully modernised to operate with the higher water recovery rate (R) without any anti-scalant and without acid; this new EDR operated with LSI at 2.29 and CaSO4 saturation level 358.9% at lower dose and lower MIRT(c). Dose and MIRT(c) are proposed to address the controlling process. Monographs for the acids and SHMP requirements, and for the desalting cost including desalting power, membrane surface area, and chemicals usage, are developed. By lowering R and polar reversal interval, EDR can be operated at MIRT(c) < 130 min; at MIRT(c0 < 130 min, desalting cost/ energy can be minimised by eliminating chemicals requirement.  相似文献   
104.
Since the traditional hard classifier can label each pixel only with one class, urban vegetation (e.g. trees) can only be recorded as either present or absent. The sub‐pixel analysis that can provide the relative abundance of surface materials within a pixel may be a potential solution to effectively identifying urban vegetation distribution. This study examines the effectiveness of a sub‐pixel classifier with the use of expert system rules to estimate varying distributions of different vegetation types in urban areas. The Spearman's rank order correlation between the vegetation output and reference data for wild grass, man‐made grass, riparian vegetation, tree, and agriculture were 0.791, 0.869, 0.628, 0.743, and 0.840 respectively. Results from this study demonstrated that the expert system rule using NDVI threshold procedure is reliable and the sub‐pixel processor picked the signatures relatively well. This study reports a checklist of the sources of limitation in the application of sub‐pixel approaches.  相似文献   
105.
We report a novel joint fabrication method for YBa2Cu3O7?x (Y123) bulk superconductors without pressure loading, based on a well‐controlled high‐temperature process. Due to the direction of the heat fluxes in a box furnace, the surfaces of the joined samples melt first, and the crystal morphology of the original YBa2Cu3O7?x bulks remains. After the joining process, part of the texture zone is used as a seed to grow new texture crystals for nucleation during cooling. Finally, a high‐quality artificial grain boundary forms without acting as a weak link, which is supported by the trapped field distribution. Details of the joint are presented, including its microstructure and micro‐orientation. Moreover, the trapped field values at 65 and 45 K are presented.  相似文献   
106.
107.
Stacked precursors of Cu, Sn, and Zn were fabricated on glass/Mo substrates by electron beam evaporation. Six kinds of precursors with different stacking sequences were prepared by sequential evaporation of Cu, Sn, and Zn with substrate heating. The precursors were sulfurized at temperatures of 560 °C for 2 h in an atmosphere of N2 + sulfur vapor to fabricate Cu2ZnSnS4 (CZTS) thin films for solar cells. The sulfurized films exhibited X-ray diffraction peaks attributable to CZTS. Solar cells using CZTS thin films prepared from six kinds of precursors were fabricated. As a result, the solar cell using a CZTS thin film produced by sulfurization of the Mo/Zn/Cu/Sn precursor exhibited an open-circuit voltage of 478 mV, a short-circuit current of 9.78 mA/cm2, a fill factor of 0.38, and a conversion efficiency of 1.79%.  相似文献   
108.
The fabrication of multifunctional nanomaterials and their subsequent use for novel applications in various branches of nanotechnology has been under intense scrutiny. Particularly in the area of nanomechanics, the design of multicomponent nanostructures with an integrated multifunctionality would enable the construction of building blocks for nanoscale analogues of macroscopic objects. Here, we introduce a new class of flexible nanostructures: metallic nanorods with polyelectrolyte hinges, synthesized using layer-by-layer electrostatic self-assembly of oppositely charged polyelectrolytes on barcode metal nanorods followed by segment-selective chemical etching. Nanorods with hinges that consist of one polyelectrolyte bilayer display considerable flexibility, but with a greater number of bilayers the flexibility of the hinge is significantly reduced. Magnetically induced bending about the polymer hinge is illustrated through the incorporation of nickel segments into the barcodes and the application of an external fluctuating magnetic field.  相似文献   
109.
110.
Porous NiTi shape memory alloy has been an active area of research for medical application due to their similar microstructure to human bone. In this study, porous product was obtained by self-propagating high-temperature synthesis (SHS) of compacts prepared from elemental nickel and titanium powders and the effects of the green porosity and preheating temperature were examined. The porosity in the synthesised products was in the range of 45–59 vol.%, with the green porosity being the primary source of final porosity. NiTi was present as the dominant phase in the porous product with other secondary intermetallic compounds and element powders. The effect of green porosity and preheating temperature was found to have an effect on the pore morphology and microstructure.  相似文献   
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