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151.
152.
Max Wardetzky Mikls Bergou David Harmon Denis Zorin Eitan Grinspun 《Computer Aided Geometric Design》2007,24(8-9):499-518
We present a family of discrete isometric bending models (IBMs) for triangulated surfaces in 3-space. These models are derived from an axiomatic treatment of discrete Laplace operators, using these operators to obtain linear models for discrete mean curvature from which bending energies are assembled. Under the assumption of isometric surface deformations we show that these energies are quadratic in surface positions. The corresponding linear energy gradients and constant energy Hessians constitute an efficient model for computing bending forces and their derivatives, enabling fast time-integration of cloth dynamics with a two- to three-fold net speedup over existing nonlinear methods, and near-interactive rates for Willmore smoothing of large meshes. 相似文献
153.
C. Llopis F. Revents L. Batet C. Pretel I. Sol 《Nuclear Engineering and Design》2007,237(18):2014-2023
The Technical University of Catalonia (UPC) has been jointly working with the Asociación Nuclear Ascó-Vandellòs (ANAV) for a number of years in order to establish, qualify and use best estimate (BE) models for the reactors under the control of ANAV. ANAV is the consortium that is responsible for operation of the Ascó and Vandellòs-II reactors. The reactors are Westinghouse-design three-loop PWRs with an approximate electrical power of 1000 MW. The existing integral plant models for each plant are currently used for many different purposes among which are support of plant operation and control. Quite a number of studies have been done in order to improve both safety and plant competitiveness. Most of these dynamic analyses were carried out in relation to transients starting at nominal full power or at least, very close to full power. This paper develops a specific use of the Vandellòs-II plant model for operation and control support at low power involving new ranges of system actuation parameters. It also examines scenarios that are somewhat different from those typically analysed. The study starts showing the results of an assessment case, which is a start-up test and provides some additional qualification, and subsequently attempts to establish calculations to support both an improvement in feed water controls and to set up operating recommendations for low-load manual operation of feed water turbo-pump. Both results hopefully, will produce an outcome, which leads to an improvement in safety and reduces reactor trip probability. 相似文献
154.
155.
This work presents a series of results about the synthesis and characterization of porous oxide thin films (thicknesses ∼
∼300 nm) prepared at low temperature by PECVD. Two different experimental strategies are described. A first one, used for
the preparation of porous SiO2 thin films, consists of the use of a polymeric sacrificial layer that is removed during deposition of the oxide thin film.
A second one, used for the preparation of TiO2 thin films, relies on the modification of some critical deposition parameters (i.e., temperature, Ar/O2 ratio in the plasma mixture, etc.). Thin films with a large variation of pore structures as evidenced by Scanning Electron
Microscopy (SEM) have been prepared by the two methodologies. The thin films have been characterised by different techniques
and some of their properties related with their microstructure assessed by ellipsometry (optical behaviour) or water contact
angle measurements (hydrophobic/hydrophilic character). A quartz crystal monitor has been used to measure water vapour adsorption/desorption
isotherms in the films. From the shape of these isotherms it is possible to estimate the type of pores existing in the different
thin films. Examples of the potential use of these porous thin films as humidity sensors or hydrophilic surfaces are reported. 相似文献
156.
A phenotypic analysis of infiltrating macrophages in rat anti-Thy1 glomerulonephritis induced by monoclonal antibody (mAb) 1-22-3 was carried out using recently reported macrophage-specific mAbs. This was combined with a more detailed quantitative analysis, counting positive cells in isolated glomeruli, to obtain more information on the roles played by macrophages in glomerulonephritis. In normal glomeruli a small number of ED1- or OX-3(anti-Ia)-positive cells but almost no ED2-, TRPM-3- or Mar-3-positive cells were observed. ED1-positive cells increased from 2 h and peaked between days 3 and 7 after mAb injection. TRPM-3-positive cells increased from day 3 and peaked on day 7, later than ED1. The numbers of OX-3-positive cells changed in parallel with those of ED1-positive cells. Mar-3, which stained blood monocytes and ED2, which is an indicator oftissue-fixed resident macrophages, did not react with glomerular infiltrating macrophages. In a double staining study, about 40% of ED1- or OX-3-positive cells costained with TRPM-3 on day 3 and the percentage increased on day 7, but hardly any cells were positive for TRPM-3 alone. This results in two different phenotypes (ED1+,ED2-,OX-3+,Mar-3-, TRPM-3- and ED1+,ED2-,OX-3+,Mar-3-,TRPM-3+) of infiltrating macrophages. We conclude that in rat anti-Thy1 glomerulonephritis, monocytes/macrophages may infiltrate the mesangium, rapidly changing their phenotype (Mar-3+ to Mar-3-) and resulting in a gradual shift to TRPM-3-positive, activated macrophages. 相似文献
157.
I Contreras R San-Millán A Agustín-Barrasa J Pontón G Quindós 《Canadian Metallurgical Quarterly》1996,136(1):17-20
A clinical study was carried out in an attempt to assess the efficacy of a newly designed electric toothbrush compared to a conventional manual toothbrush using the American Dental Association's protocol for evaluating toothbrushes. An Oral-B 35 manual toothbrush, which served as the control, was compared to the Plaq & White125 electric toothbrush. Examinations were performed by two calibrated examiners at baseline, day 15 and day 30. Examinations included the gingival index, plaque index and bleeding index. Mean indices were calculated and compared between the two brushes using the repeated measures multiple analysis of variance. No statistically significant differences between the mean indices on the three examination days were observed following the use of the manual or the electric toothbrushes. The results of this study demonstrate that the electric toothbrush was numerically more effective than the manual toothbrush in reducing supragingival plaque levels, either before or after brushing, at each examination date compared to baseline plaque values. However, this difference was not statistically significant. This and other findings concluded that the Plaq & White toothbrush is comparable to the control ADA-accepted toothbrush. 相似文献
158.
159.
MP Amador Rodríguez A Artal Cortés E Rebollar Torres A Idoipe Tomás P Palomo Palomo J Martínez Trufero 《Canadian Metallurgical Quarterly》1998,13(4):198-204
A B16 melanoma-specific CD8+ T cell line (AB1) was established from the spleen cells of C57BL/6 mice cured of B16 melanoma with interleukin (IL)-12 treatment. The AB1 line exclusively used T cell receptor Vbeta11. The AB1 cells exhibited a cytolytic activity against both syngeneic B16 melanoma and allogeneic P815 mastocytoma, whereas a cold inhibition assay revealed specificity of the AB1 cells against B16 melanoma. Their lostability to kill a class I loss variant of B16 melanoma was restored by the transfection of H-2Kb gene. In addition, their interferon (IFN)-gamma production was significantly suppressed by the addition of anti-H-2Kb monoclonal antibody, and RT-PCR analysis showed that the AB1 line expressed the mRNA encoding IFN-gamma, but not IL-4 or IL-10. The experiment using synthetic peptides of tyrosinase-related protein-2 (TRP-2) revealed that the AB1 cells could recognize TRP-2(181-188) peptide. Moreover, the AB1 cells showed an in vivo antitumor effect against established pulmonary metastases of B16 melanoma. Overall, these results indicate that the Tc1-type Vbeta11+ AB1 cells exert an antitumor activity against syngeneic B16 melanoma through recognition of TRP-2(181-188) peptide in an H-2Kb-restricted manner. 相似文献
160.
L Baró JC Hermoso MC Nú?ez JA Jiménez-Rios A Gil 《Canadian Metallurgical Quarterly》1998,77(11):1978-1983
Intravenous injection of stearoyl vanillylamide (C18-VA), a nonpungent capsaicin (CAP) analog, enhances adrenaline secretion significantly and as effectively as CAP in rats. Because swimming capacity was enhanced by CAP in mice due to CAP-induced adrenal catecholamine secretion, we investigated the effects of oral administration of C18-VA on swimming capacity using an adjustable-current water pool. Male Std ddY 6-wk-old mice were fed a commercial diet for this study and one group was orally administered C18-VA via a stomach tube. Treated mice were able to swim longer before exhaustion than the control mice (62.9 +/- 5.6 vs. 49.6 +/- 7. 0 min, P < 0.05). The swimming capacity of two groups administered C18-VA (0.02 and 0.033 mmol/kg) was significantly greater than that of those administered vehicle alone, (P < 0.05). Substance P concentration in cerebrospinal fluid, which is involved in pain transmission and is the first direct measure of pungency, was not affected by C18-VA administration. In an experiment examining the effects of C18-VA on serum adrenaline concentration, adrenaline was significantly greater in C18-VA treated mice than in controls at 2-h post-dose (C18-VA group, 26.09 +/- 2.82; control group 13.29 +/- 0. 96 microg/L, P < 0.01). In a separate study free fatty acids in serum were elevated in treated mice at 2-h post-dose (P < 0.01). While serum glucose concentration was not affected. These results suggest that C18-VA increased swimming capacity of mice via adrenaline release, independent of pungency. In addition, the present study suggests the usefulness of its application to humans. 相似文献