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The operating characteristics of a water vapor-helium laser working at 28 microm are presented. Comparison is made of power output in continuous and pulsed operation for various gas mixtures and discharge currents for the same laser cavity. 相似文献
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Gilles Rochefort Frédéric Champagnat Guy Le Besnerais Jean-Fran?ois Giovannelli 《IEEE transactions on image processing》2006,15(11):3325-3337
Super-resolution (SR) techniques make use of subpixel shifts between frames in an image sequence to yield higher resolution images. We propose an original observation model devoted to the case of nonisometric inter-frame motion as required, for instance, in the context of airborne imaging sensors. First, we describe how the main observation models used in the SR literature deal with motion, and we explain why they are not suited for nonisometric motion. Then, we propose an extension of the observation model by Elad and Feuer adapted to affine motion. This model is based on a decomposition of affine transforms into successive shear transforms, each one efficiently implemented by row-by-row or column-by-column one-dimensional affine transforms. We demonstrate on synthetic and real sequences that our observation model incorporated in a SR reconstruction technique leads to better results in the case of variable scale motions and it provides equivalent results in the case of isometric motions. 相似文献
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Y Zhao C Escot T Maudelonde C Puech P Rouanet H Rochefort 《Canadian Metallurgical Quarterly》1993,53(12):2901-2905
We evaluated levels of mannose-6-phosphate/insulin growth factor-II receptor (M6P/IGFII-R) RNA in 37 breast cancer tumors by quantitative in situ hybridization using a computer-aided image analyzer and compared them to cathepsin D RNA and protein levels in the same tissues. Breast cancer cells expressed more cathepsin D and M6P/IGFII-R RNA than fibroblasts in the same tumors. We found a significant increase of cathepsin D RNA (P = 1 x 10(-5)) and M6P/IGFII-R RNA (P = 0.02) in breast cancer cells compared to epithelial cells of benign mastopathies. There was a positive correlation (r = 0.65; P = 1 x 10(-5)) between M6P/IGFII-R and cathepsin D RNA levels measured on serial sections. This contrasted with the inverse relationship of these 2 RNA species in breast cancer cell lines where estrogen down-regulates M6P/IGFII receptor RNA levels. Moreover, in vivo we found no correlation between the M6P/IGFII-R RNA level and menopausal or estrogen receptor status, suggesting that the in vivo regulation of M6P/IGFII-R RNA differs from its in vitro regulation in cell lines. The M6P/IGFII-R RNA level was not correlated with cathepsin D status, histological grade, and tumor size but was significantly higher in lymph node-positive tumors (P = 0.047). The M6P/IGFII-R could therefore be an additional parameter to predict aggressive breast cancers, complementing cathepsin D assays and other more classical prognostic parameters. 相似文献
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V Bellingard B Hédon F Capony A Defrenne H Rochefort T Maudelonde 《Canadian Metallurgical Quarterly》1996,55(3):604-612
To assess endometrial fibroblast-cytotrophoblast interactions, we used a coculture system allowing analysis of the potential cell morphology modifications and protein secretion variations possibly involved in endometrial invasion arrest. Stromal cells and cytotrophoblasts were isolated from endometrial biopsies and first-trimester placental villi, respectively. In our culture conditions, a 57-kDa protein that was secreted by cultured fibroblasts but was absent in the 4-day coculture medium was found to be identical to prometalloproteinase-3 (proMMP-3) through determination of amino acid sequences of NH2-terminal and internal peptides. Northern blotting analysis of endometrial fibroblast total RNA showed a 38.6% metalloproteinase-3 (MMP-3) mRNA inhibition by 4-day 10(-6) M R5020 treatment. Inhibition of proMMP-3 secretion was weak when cytotrophoblasts were cultured for 4 days in a polycarbonate membrane insert over cultured fibroblasts without possible cell contact in spite of high levels of progesterone produced by cytotrophoblasts. Furthermore, cytotrophoblasts cultured on a monolayer of endometrial fibroblasts became syncytia, and most of the fibroblasts were decidualized. The closeness of the two cell types allowed paracrine relationships that might facilitate the progesterone action. Since MMP-3 is known to activate collagenases, inhibition of its secretion by cell contact might be a mechanism of invasion arrest for trophoblast cell migration. 相似文献
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Protic ionic liquids (PILs) based on 2-methylpyridine (2-MPy) and trifluoroacetic acid (TFA) have been synthesized under multiple conditions and with different proportions of their constituents. These PILs present a brown color of variable intensity and the factors responsible for the presence of these impurities have been examined. UV–vis spectroscopy analyses revealed that both TFA and 2-MPy can be thermally degraded during the synthesis process. Distillation of the IL can be used to quickly obtain mixtures without any traces of coloration, but can leads to a severe alteration of the relative proportion of the constituents. This work shows that high-yield syntheses of PILs obtained with different contents in colored impurities can be compared to evaluate the effect of these impurities not only on the electrochemical behavior (on Pt and on GC) but also on the physicochemical properties of interest for PILs as applications in electrochemistry (conductivity, density, and viscosity). 相似文献
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Crystalline ruthenium dioxide (RuO2) has been ball-milled in an O2 atmosphere and the changes in the physico-chemical properties induced by different milling atmospheres (Ar and O2) or milling sequences have been established. Cyclic voltammetry and BET measurements were used to evaluate the electrochemically active surface charge (, expressed in C g−1) and the specific surface area (expressed in m2 g−1), respectively. The extent of oxygen uptake in the processed samples was determined by X-ray photoelectron spectroscopy (XPS). The value of RuO2 milled under O2 for 30 h (sample S4) is 120.7 C g−1, a factor of two higher than the value of RuO2 milled under Ar for the same period of time (sample S1, 60.3 C g−1). A still higher value is obtained when the O2 atmosphere of the crucible is frequently replenished (sample S5, 138.7 C g−1) or when the milling operation is prolonged up to 81 h (sample S6, 160.5 C g−1). These changes are paralleled by a variation of the BET surface area, which increases from 24 m2 g−1 for sample S1 to 51.5 m2 g−1 for sample S5. The concentration ratio [Obound to Ru]/[Ru] determined by XPS increases steadily from sample S1 to sample S6, indicating that the amount [Obound to Ru] increases with the exposure of RuO2 to oxygen during the milling process. All these changes are explained by the fact that freshly exposed RuO2 surfaces created during the milling process react with O2 molecules, thereby lowering the surface energies and the tendency of the milled material to cluster into larger aggregates. 相似文献
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T Maudelonde C Escot P Pujol P Rouanet A Defrenne JP Brouillet H Rochefort 《Canadian Metallurgical Quarterly》1994,(14):2049-2053
We have previously shown that 3 weeks of treatment with tamoxifen, of patients with primary breast carcinomas, increased cytosolic cathepsin D protein in oestrogen receptor (ER) positive tumours [Maudelonde et al., Cancer 1989, 63, 1265-1270]. In order to investigate the mechanism of this increase and to eliminate a transient flare-up effect, we semi-quantified cathepsin D RNA levels by in situ hybridisation in 32 breast carcinomas from patients treated with tamoxifen for 3 weeks prior to surgery and in 35 breast cancer patients receiving no tamoxifen. We found that tamoxifen increased cathepsin D RNA level regardless of the ER status of the tumours. In ER positive tumours, tamoxifen increased the cathepsin D RNA level to the same extent as cytosolic cathepsin D protein but not in ER negative tumours. The induction of cathepsin D RNA by tamoxifen in ER positive tumours was probably due to its agonist activity, also observed in vitro in breast cancer cell lines. These results suggest that the cathepsin D gene is inducible by oestrogens in ER positive breast cancer as it is in breast cancer cell lines. 相似文献