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171.
R. Todorov 《Scientometrics》1992,23(2):319-334
A co-heading analysis is proposed for representing the subject content of scientific journals. It is based on the subject headings assigned to documents before their input in bibliographic databases. The method utilizes specifically the co-appearance of headings in the document records to display the subject scope of a given journal not only by the topics covered but by their relationships as well. This analysis is applied in superconductivity for displaying the content of some physics journals using data from 1984 Physics Abstracts. The results (in the form of inclusion maps) could help information scientists and library staff in evaluating and selecting appropriate journals.  相似文献   
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The modal method is applied to the problem of conical diffraction on a rectangular slit metallic grating lying on an arbitrary multilayer medium. In the approximation of the surface impedance boundary condition on the grating walls, a single matrix equation is obtained, whose coefficients are expressed simply by the reflectivities on the different layers. A simple and comprehensive treatment is thus obtained for virtually any multilayer system. The method is illustrated for the case of a cavity formed by a planar metallic mirror and a grating, as well as the system formed by a doped layer with Drude susceptibility in a substrate below the grating. The method could be useful for the design of near- and far-infrared devices.  相似文献   
177.
The time-course of changes in casein and gluten utilization was elucidated in rats in 2 experiments lasting 52 and 84 days by means of determining the protein effectiveness coefficient (PEC). The PEC was measured every other 4 days. Casein utilization decreased continuously and almost rectilinearly, whereas gluten utilization first rose (adaptation) and then descended (deadaptation). It is concluded that the time-course of changes in utilization of unbalanced wheat protein is linked not only with restitution of the enzymatic systems but also with mobilization and depletion of the reserve possibilities of the body.  相似文献   
178.
In this study, we evaluated the effect of different matrices (MRS, milk and milk with inulin) on the tolerance of probiotic strains (Lactobacillus acidophilus La‐5 and Bifidobacterium animalis subsp. lactis BB‐12) to simulated conditions similar to those found in the gastrointestinal tract. Both probiotic strains demonstrated a significantly lower viability after exposure to in vitro gastric and intestinal conditions, and B. animalis subsp. lactis BB‐12 showed higher survival during the test compared to L. acidophilus La‐5 in all tested matrices. Milk and inulin protected probiotics from in vitro gastrointestinal stress. These results suggest that it is critical to formulate the food matrix to be used as probiotic carrier.  相似文献   
179.
Food Science and Biotechnology - The aim of this study was to investigate the different immunological and antimicrobial properties of breast milk from women with (W) or without (WO) vaginal yeast...  相似文献   
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