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1.
Nitrous oxide produced a dose-related "analgesia" in mice (median effective dose, 55 percent). The analgesia was evaluated by means of a phenylquinone writhing test. Narcotic antagonists or chronic morphinization reduced nitrous oxide analgesia. Either nitrous oxide releases an endogenous analgesic or narcotic antagonists have analgesic antagonist properties heretofore unappreciated.  相似文献   
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An infrared camera based on a 256×256 focal plane array (FPA) for the second atmospheric window (3–5 μm) has been realized for the first time with InAs/GaSb short period superlattices (SLs). The SL detector structure with a broken gap type-II band alignment was grown by molecular beam epitaxy on GaSb substrates. Effective bandgap and strain in the superlattice were adjusted by varying the thickness of the InAs and GaSb layers and the controlled formation of InSb-like bonds at the interfaces. The FPAs were processed in a full wafer process using optical lithography, chemical-assisted ion beam etching, and conventional metallization technology. The FPAs were flip-chip bonded using indium solder bumps with a read-out integrated circuit and mounted into an integrated detector cooler assembly. The FPAs with a cut-off wavelength of 5.4 μm exhibit quantum efficiencies of 30% and detectivity values exceeding 1013 Jones at T=77 K. A noise equivalent temperature difference (NETD) of 11.1 mK was measured for an integration time of 5 ms using f/2 optics. The NETD scales inversely proportional to the square root of the integration time between 5 ms and 1 ms, revealing background limited performance. Excellent thermal images with low NETD values and a very good modulation transfer function demonstrate the high potential of this material system for the fabrication of future thermal imaging systems.  相似文献   
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The corrosion of the simulated high level waste glass GP WAK1 in synthetic clay pore solution was studied in batch-type experiments at 323 and 363 K with special focus on the effect of high carbonate concentration in solution. The corrosion rate after 130 days was <10−4 g m−2 d−1 - no significant effect of the carbonate was identified. During glass corrosion, crystalline secondary phases (powellite, barite, calcite, anhydrite and clay-like Mg(Ca,Fe)-silicates) were formed. To obtain a molecular level picture of radionuclide speciation within the alteration layer, spectroscopic methods have been applied including grazing incidence X-ray absorption spectroscopy (XAS) to study the structural changes in the coordination of uranyl upon alteration layer formation. The number of equatorial oxygen atoms increases from 4 in the bulk glass to 5 in the alteration layer. Furthermore, reduced coordination symmetry was found. Hectorite, a frequently observed secondary clay mineral within the glass alteration layer, was synthesized in the presence of trivalent f-elements (e.g. Eu) and structurally characterized using time-resolved laser fluorescence spectroscopy. Structural incorporation into the octahedral layer is indicated.  相似文献   
4.
Scatter analysis is an effective method for the characterization of thin film components. The new highly sensitive table top system ALBATROSS-TT (3D-Arrangement for Laser Based Transmittance, Reflectance and Optical Scatter Measurement-Table Top) has been developed at the Fraunhofer Institute in Jena to meet the specific requirements for close-to-process applications. Extremely high sensitivity with a noise equivalent angle resolved scatter level of 2×10(-8)?sr(-1), full three-dimensional spherical measurement capability, and an instrument size as small as 0.8?m×0.8?m×0.8?m have been achieved. Details of specifications, optical components, and software are presented, including a comparison to our laboratory system. Anisotropy analysis of diamond-turned aluminum substrates as well as substrate and coating characterization are demonstrated as examples of application.  相似文献   
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Forty-eight patients with nephrotic syndrome were evaluated prospectively; the studies included inferior venacavagrams and ventilation perfusion lung scans. Eleven patients were found to have renal vein thrombosis (RVT). Eight of 21 patients with membranous glomerulonephritis (MGN) or membranoproliferative glomerulonephritis (MPGN) has RVT (38%). Clinical, laboratory, and pathological findings were not different among those patients with MGN and MPGN whether RVT was present or not. Patients with diabetic nephropathy or lupus nephritis did not have RVT. There was a high incidence of other thromboembolic phenomena as well as asymptomatic perfusion defects demonstrated by the lung scan, especially in patients with MGN or MPGN. These data suggest the disease process underlying the nephrotic syndrome may play a paramount role in the genesis of RVT or thromboembolic phenomena.  相似文献   
7.
Studied auditory sensitivity and changes of selected structures of the external, middle, and inner ear in 31 Mongolian gerbil neonates. Data demonstrate an improvement in sensitivity to sound associated with postnatal changes in the morphology of the ear. Cochlear potentials and a concomitant reflex response to sound were observed 14 days after birth. At this state of postnatal development the organ of Corti appeared mature, the external auditory canal was open, but mesenchyme was present within the tympanic bulla. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Water Resources Management - Real-time forecasting plays a valuable role in the early warning system framework by reducing damage. However, signal loss in telemetric monitoring networks tends to...  相似文献   
10.
The seminal observation that secretion of the adipocyte-derived hormone leptin was induced by inflammatory challenge has been expanded upon to demonstrate the importance of the pro-inflammatory cytokines, especially tumor necrosis factor (TNF)-alpha, in inflammatory hyperleptinemia. Initially, it was thought that cytokine-induced hyperleptinemia might somehow be involved in the anorexia and cachexia that often accompany chronic infectious, neoplastic, and autoimmune disease. While the role of leptin in disease-associated anorexia and cachexia appears tenuous in light of recent findings, there is evidence that the hyperleptinemia induced by cytokines is an integral part of the acute phase response and necessary for comprehensive immunocompetence. This hints at the existence of an integrated communication network, wherein the energy status of the animal impacts its ability to fight pathogens.  相似文献   
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