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981.
Textural evolution in electrodeposits is strongly affected by foreign species in the electrolyte and also by the co-deposition of hydrogen. The effects of foreign species on textural development in electrodeposits were studied by employing a Monte Carlo model. This model is based on physical principles and incorporates parameters which are used to control electrodeposition processes. An attempt was made in the simulation to reflect the basic process of the deposit growth, and to identify the factors responsible for the texture formation and its variation with the deposition condition. It is assumed that the texture of the deposit results from the minimization of the free energy of the system. Based on this assumption, it was demonstrated that the surface-energy anisotropy played an important role in the formation of fibre texture. In particular, the model can be used to simulate textural evolution under the influence of adsorbed foreign species, because the surface-energy anisotropy is modified by the adsorbed foreign species. Part I of the paper presents results of our studies on iron electrodeposition with the emphasis on the effect of hydrogen adsorption on iron deposit texture. Relevant experimental results have also been presented to corroborate the simulation study. Part II of the paper presents simulation studies of textural evolution in copper deposits under the influence of adsorbed potassium and chloride ions. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
982.
This paper describes a prototype video coding platform meant for the conception and testing of multimedia products such as next-generation videophones. The platform is largely based on ITU-T Recommendation H.263, with a number of additional object-oriented quality enhancement features which make it especially well suited for very low bit-rate coding of “head-and-shoulders” video material typical of real-time multimedia applications, video teleconferencing, and video telephony. These features consist of: (1) segmentation into objects of interest, (2) segmentation-based prefiltering, (3) model-assisted rate control, (4) adaptive vector quantization, and finally (5) segmentation-based postfiltering. In the spirit of Recommendation H.263, these enhancements are modular and can be selectively turned on or off, thereby enabling a wide variety of coding modes  相似文献   
983.
An "Occam algorithm" learning model maintains a tentative hypothesis consistent with past observations and, when a new observation is inconsistent with the current hypothesis, updates to the next-simplest hypothesis consistent with all observations. In previous work, observations were assumed to be stochastically independent. This paper initiates study of such models under weaker Markovian assumptions on the observations, In the special case where the sequence of hypotheses satisfies a monotonicity condition, it is shown that the number of mistakes in classifying the first t observations is O(√t log 1/πi), where πi is the stationary probability of the initial state, i, of the Markov chain.  相似文献   
984.
A model for the calculation of the current-voltage characteristics of strained In0.52Al0.48As/InxGa1-xAs on InP substrate High Electron Mobility Transistors (HEMT's), based on a variational charge control model, is presented. A polynomial fit of the two-dimensional electron gas (2DEG) density is used for the calculation of the current-voltage characteristics. The effect of strain is introduced into the 2DEG density versus gate voltage relation. Very good agreement between the calculated and measured I-V characteristics was obtained. In addition, our results show that, for an indium mole fraction of the InxGa1-xAs channel in the range 0.53-0.60, increasing the indium mole fraction lowers the threshold voltage and hence increases the drain current at the same gate bias  相似文献   
985.
The paper presents a review of results concerning the aspartic proteinase cathepsin D and its role in tumor invasion and metastasis. Special attention was paid to the clinical prognostic value of cathepsin D determination in the breast cancer cytosol.  相似文献   
986.
The authors report an exceedingly rare complication of rheumatoid arthritis, i.e. acquired hemophilia due to anti-factor VIII autoantibody production. Treatment with intravenous immune globulin ensured control of hemorrhagic manifestations by inducing a transient rise in factor VIII level.  相似文献   
987.
Recommendations resulting from a JCAHO survey can be a true blessing as they force nursing departments to assess critically their professional practice and documentation systems. Systematic preparation, begun at least two years prior to the survey, includes Nursing Administration, a Nursing Documentation Task Force and all staff nurses. Educational consultants assigned to each unit bring nurses up-to-date on nursing process and nursing diagnosis. Mock surveys and cross-training in chart review prepare staff nurses for confident participation in the accreditation process.  相似文献   
988.
989.
A total of 259 Gram-negative Porphyromonas-like rods isolated from subgingival plaque samples of 16 family-owned dogs with naturally occurring periodontitis were characterized phenotypically by biochemical reactions, metabolic end products and enzymatic activities (API-ZYMTM, RoscoTM). Four distinct groups were found. Group A isolates (63) were asaccharolytic, lipase negative, trypsin positive and produced phenylacetic acid (PAA) from peptone-yeast extract glucose broth. Unlike P. gingivalis strains they were catalase positive. Group B isolates (42) differed from those of group A by a positive lipase reaction and from those of group D by failing to ferment sugars. Group C isolates (88) were asaccharolytic and did not produce PAA. They were alpha-fucosidase, N-acetyl-beta-glucosaminidase (beta-NAG) and trypsin negative, resembling P. endodontalis, but unlike human isolates, they were catalase positive. Subgroup C.1 isolates (6) differed from those of parent group C by producing minor amounts of PAA, and subgroup C.2 isolates (12) were beta-NAG positive. Group D isolates (46) were weakly fermentative, lipase, catalase and trypsin positive, and produced PAA. They resembled the B (P.) salivosus type strain which, in our hands, fermented weakly glucose, lactose and mannose. Two isolates could not be assigned to any of the previous groups.  相似文献   
990.
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