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Bulletin of Engineering Geology and the Environment - A better understanding of the spatiotemporal evolution of landslides in urban zones is a key factor in assessing the risk of future slides...  相似文献   
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In pH 10.0 buffers, tetrakis(4-sulfonatophenyl)porphyrin (TSPP) has been found to form complexes with malto-oligosaccharides from maltose to maltoheptaose and soluble starch. The peak of the electronic absorption of TSPP is monotonously shifted to longer wavelengths with an increase in the number of D-glucopyranose residues in malto-oligosaccharide. Zn(II) TSPP (ZnTSPP) and Fe(III) TSPP (FeTSPP) also form complexes with malto-oligosaccharides. In the case of FeTSPP, the absorption peak is remarkably red shifted in pH 10.0 buffers that contain maltopentaose. The equilibrium constant of TSPP for the formation of the complex is increased with increasing numbers of D-glucopyranose residues, whereas the equilibrium constants of ZnTSPP and FeTSPP for maltopentaose are extraordinarily large compared to maltotetraose and maltohexaose. Induced circular dichroism spectra of TSPP, ZnTSPP, and FeTSPP in malto-oligosaccharide solutions differ from one another, suggesting different association modes of the complexes.  相似文献   
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The authors evaluated, using computer image analysis system, 15 renal biopsy specimens from patients with MCD and 15 from patients with FSGS. As a control group 5 biopsy and 10 autopsy renal specimens were used. These studies revealed, that in MCD glomeruli showed proliferative changes unrecognizable by light microscopy. In FSGS glomeruli without sclerotic changes were larger than in controls and showed glomerular cells proliferation (per unit of glomerular area) similar to MCD. FSGS in comparison with MCD showed larger glomeruli and prominent interstitial fibrosis. These observations appeared to be helpful in distinguishing MCD and recent forms of FSGS. There were no correlations between relative interstitial volume and glomerular changes in MCD as well as in FSGS. The authors concluded, that histomorphometry can't be used instead of morphological examinations of renal biopsy specimens, but it gives objective informations about progression of the illness and may be useful in differential diagnosis of selected cases of MCD and FSGS.  相似文献   
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We examined the influence of sevoflurane and isoflurane anesthesia on renal function in elderly patient who underwent gastrectomy. Plasma inorganic fluoride level was significantly higher in sevoflurane group compared with isoflurane group from 3 hours after the beginning of anesthesia to the 3rd operative day. In contrast, parameters such as urinary beta 2 microglobulin, urinary N-acetyl-beta-D-glucosaminidase, and urinary gamma-GTP activities increased in both groups, but the increase was not significant. Serum BUN and creatinine levels were within normal limits. These results suggest that elderly patients without renal dysfunction appear unlikely to have any significant problem after prolonged sevoflurane anesthesia.  相似文献   
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An improved deep submicrometer (0.25 μm) MOSFET radio-frequency (RF) large signal model that incorporates a new breakdown current model and drain-to-substrate nonlinear coupling was developed and investigated using various experiments. An accurate breakdown model is required for deep submicrometer MOSFETs due to their relatively low breakdown voltage. For the first time, this RF nonlinear model incorporates the breakdown voltage turnover trend into a continuously differentiable channel current model and a new nonlinear coupling circuit between the drain and the lossy substrate. The robustness of the model is verified with measured pulsed I-V, S-parameters, power characteristics, harmonic distortion, and intermodulation distortion levels at different input and output termination conditions, operating biases, and frequencies  相似文献   
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In this study, a semi-interpenetrating polymer network (semi-IPN) gel, which consists of an amphiphilic N,N-dimethylacrylamide-co-N-isopropylacrylamide (DMAA-co-NIPAM) gel and an interpenetrating zwitterionic thermosensitive poly(N-isopropylacrylamide-co-N,N-dimethyl(acrylamidopropyl)ammonium propane sulfonate) (poly(NIPAM-co-DMAAPS)) was prepared. The thermosensitive behavior of the semi-IPN gel was investigated in a buffer solution composed of a relatively high concentration of sodium chloride and sodium citrate as salts, and sodium dodecyl sulfate as a surfactant, which are generally used as a buffer solution in biochips. At low temperatures, the semi-IPN gel in the buffer solution was absolutely transparent; however, when the gel was heated, the gel became milky white or opaque without a large change in the gel size. The network of the transparent gel is homogeneous, whereas that of the opaque gel consists of coarse and dense parts. Such a structural change in the gel network was confirmed by the temperature dependence of the permeability of the buffer solution through the semi-IPN gel membrane. The permeability increased drastically when the gel became opaque because of heating.  相似文献   
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This paper discusses characteristics of a new digital simulator for protection relay testing. The most demanding design requirement is computation of fault transients under the condition of real-time change of power system configuration due to relay operation. This problem is solved using EMTP computational techniques enhanced with novel numerical solutions for dynamic power system configuration change and nonlinear element modeling. An advanced computer architecture is utilized to achieve further optimization of the execution time for the transients computation code. The main advantage of this design is the use of conventional single processor computer architecture in combination with advanced digital signal processors (DSPs). This makes this simulator an off-the-shelf product with all the benefits of commercially available computers priced at a relatively low cost  相似文献   
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This paper presents implementation details describing a new design of a real-time digital simulator for relay testing. The simulator is developed under requirements to utilize, as much as possible, low cost commercial computer hardware and system software support. The other requirements ask for a three-terminal support with extensive graphical user interface (GUI) and a simulation time step as low as 50 μs. Such a design has been built for Western Area Power Administration (WAPA), USA, and fully validated using a model of an actual WAPA power system section. The simulator was delivered to WAPA in March 1994  相似文献   
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