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T Higashiguchi PO Hasselgren K Wagner JE Fischer 《Canadian Metallurgical Quarterly》1993,17(4):307-314
The purpose of this study was to determine the etiologic factors of denture stomatitis. Fifteen subjects with clinical evidence of localized simple denture stomatitis, fifteen subjects without clinical signs of denture stomatitis, and forty-five subjects with clinical evidence of generalized simple denture stomatitis were investigated clinically and mycologically. Subjects were evaluated according to age, sex, duration of denture usage, smoking habits, frequency of denture brushing, overnight denture wearing, pH level of saliva and degree of candidal colonization and candidal formation. Salivary samples and swabs were taken from the palate and the mucosal surfaces of the dentures investigated mycologically in order to identify the yeast colonies. Smears were taken from the palate and investigated in order to identify candidal formation. No statistically significant relationship was found between denture stomatitis and age, sex, duration of denture usage, frequency of denture brushing, overnight denture wearing or pH level of saliva. There was however, a statistically significant relationship between denture stomatitis and denture hygiene, smoking habits, candidal colonization and candidal formation. 相似文献
44.
A test designed to separate those undergoing thoracic surgery without complications and those with complications must be both highly specific and sensitive. Clearly, the difference between patients at opposite ends of the population curves is easy to identify. Spirometry can be helpful for screening, although it is not a very discriminating test. If patients fall in the overlap region between the populations, however, it is impossible to discern the risks with any certainty using low-yield tests. A test with higher sensitivity, specificity, and predictive values is necessary to ascertain such marginal differences. With this kind of analysis at hand, preoperative testing can be divided into three predictive value groups. Calculating the predictive value of each preoperative test can provide a comparative measure of usefulness of discriminative power (Table 1). In this way, spirometry, blood gas analysis, and stair climbing tolerance are shown to be poor predictors of outcome. An intermediate predictive value can be achieved using diffusion capacity, exercise-induced decreases in O2 saturation, and exercise PVR. High predictive value can be accomplished with combination indexes (PPP, possibly PRQ), measurement of VO2 at 40 watts of exercise, or VO2max. Logic dictates a step-wise preoperative evaluation using prediction value analysis (Fig.4). A flow decision chart for the preoperative evaluation of patients for pulmonary resection begins with exercise oximetry, spirometry, and blood gas analysis as general screening tests to separate those patients at minimal or no risks for complications from those patients that require further evaluation. Functional indexes (PPP, PRQ) or exercise testing can aid further in the selection of those patients in whom a nonsurgical option should be considered. Flow decision chart for the preoperative evaluation of patients for pulmonary resection should continue to evolve as new information about outcome studies is gathered. Examination of outcome data will provide us with reduction of the size of the nonoperable population, so that we can deny only those patients who truly pose a prohibitive risk. 相似文献
45.
Ricardo Garcia-Padron Dan Loyd Stefan Sjökvist 《Subsurface Sensing Technologies and Applications》2002,3(2):125-150
One promising method of locating buried objects, such as land mines, is to use optical systems for detecting contrasts in surface temperature. With enhanced knowledge about the interacting physical processes behind these temperature contrasts, it is possible to improve detection precision. In such a context, moisture movement in the soil and moisture evaporation from the surface have been found to be of particular interest. This study was based on indoor experiments on wet and dry sand exposed to radiation from a solar panel. Simulations of heat and moisture transfer conducted with a one-dimensional model are also presented for the experiments. The calculations were successful in accurately predicting surface temperatures for both wet and dry sand, making it possible to predict surface temperatures under different conditions. These findings will contribute to increasing the probability of successful detection of buried objects under real conditions using optical methods. 相似文献
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Dr. H. Fischer 《Computing》1989,41(3):261-265
The paper deals with a special problem in Automatic Differentiation. Letf be a rational function ofn variables, let #(f) denote the number of operations to evaluatef(x), letg denote the gradient off. Many algorithms for minimizingf(x) require the scalar productg(u) tv. In the standard method for computingg(u) tv the amount of work grows withn·#(f). In this note a new method for computingg(u) tv is presented. The new method is considerably faster, its amount of work only grows with #(f). 相似文献
49.
In order to increase the efficiency of waste utilization in thermal conversion processes, pre-treatment is advantageous. With the Herhof Stabilat® process, residual domestic waste is upgraded to waste-derived fuel by means of biological drying and mechanical separation of inerts and metals. The dried and homogenized waste-derived Stabilat® fuel has a relatively high calorific value and contains high volatile matter which makes it suitable for gasification. As a result of extensive mechanical treatment, the Stabilat® produced is of a fluffy appearance with a low density. A two-stage gasifier, based on a parallel-arranged bubbling fluidized bed and a fixed bed reactor, has been developed to convert Stabilat® into hydrogen-rich product gas. This paper focuses on the design and construction of the configured laboratory-scale gasifier and experience with its operation. The processing of low-density fluffy waste-derived fuel using small-scale equipment demands special technical solutions for the core components as well as for the peripheral equipment. These are discussed here. The operating results of Stabilat® gasification are also presented. 相似文献
50.
Stefan Kasapis 《International Journal of Food Science & Technology》2002,37(4):403-413
The structural properties of mixtures of pectin, oxidized starch and glucose syrup were investigated using small deformation dynamic oscillation. In the absence of added calcium, preparations of low methoxy pectin with glucose syrup formed viscous solutions, which remained crystal-free at subzero temperatures. Samples of oxidized starch and glucose syrup, on the other hand, exhibited solid-like behaviour because of the crystalline nature of the amylose-like helices. Mixtures of the two polysaccharides with the co-solute clearly showed phase inversion from liquid to solid-like behaviour with increasing amounts of starch in the formulation. The transformation was reflected in the textural properties of samples, which varied from thick solutions to firm gels. The viscoelasticity of the system was modified further by the introduction of high methoxy pectin. Preparations of high methoxy pectin and glucose syrup formed rubbery gels whose amorphous nature underwent a glass transition during cooling. 相似文献