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61.
M Delgado EJ Munoz-Elias Y Kan I Gozes M Fridkin DE Brenneman RP Gomariz D Ganea 《Canadian Metallurgical Quarterly》1998,273(47):31427-31436
62.
Clients are leaving the hospital "quicker and sicker," and they frequently have acute care needs that must be met by resources outside the hospital setting. Community resources are diverse, vary widely from place to place, and have no central administration. Thus, using them can be challenging for both the nurse, client, and family. Reimbursement mechanisms underlie a person's ability to use resources and receive health care. By presenting two actual case scenarios where clients have mobility problems commonly seen by orthopaedic nurses, the authors discuss the community resources available, avenues of access to them, and their reimbursement mechanisms. 相似文献
63.
64.
PW Roelvink A Lizonova JG Lee Y Li JM Bergelson RW Finberg DE Brough I Kovesdi TJ Wickham 《Canadian Metallurgical Quarterly》1998,72(10):7909-7915
Attachment of an adenovirus (Ad) to a cell is mediated by the capsid fiber protein. To date, only the cellular fiber receptor for subgroup C serotypes 2 and 5, the so-called coxsackievirus-adenovirus receptor (CAR) protein, has been identified and cloned. Previous data suggested that the fiber of the subgroup D serotype Ad9 also recognizes CAR, since Ad9 and Ad2 fiber knobs cross-blocked each other's cellular binding. Recombinant fiber knobs and 3H-labeled Ad virions from serotypes representing all six subgroups (A to F) were used to determine whether the knobs cross-blocked the binding of virions from different subgroups. With the exception of subgroup B, all subgroup representatives cross-competed, suggesting that they use CAR as a cellular fiber receptor as well. This result was confirmed by showing that CAR, produced in a soluble recombinant form (sCAR), bound to nitrocellulose-immobilized virions from the different subgroups except subgroup B. Similar results were found for blotted fiber knob proteins. The subgroup F virus Ad41 has both short and long fibers, but only the long fiber bound sCAR. The sCAR protein blocked the attachment of all virus serotypes that bound CAR. Moreover, CHO cells expressing human CAR, in contrast to untransformed CHO cells, all specifically bound the sCAR-binding serotypes. We conclude therefore that Ad serotypes from subgroups A, C, D, E, and F all use CAR as a cellular fiber receptor. 相似文献
65.
专家系统是人工智能的一个分支,是一种模拟专家决策能力的计算机系统,知识库是系统的重要组成部分,是系统的核心。本文结合纺织工艺设计及管理专家系统介绍了基于知识的专家系统的概念和结构,对系统中知识的获取、存储方式予以说明.并对其知识的表示方法加以阐述。 相似文献
66.
L. REIS A. FONSECA M. DE FREITAS 《Fatigue & Fracture of Engineering Materials & Structures》2004,27(9):873-877
This work describes the present methodology used on Portuguese Air Force (PoAF) aircrafts for fatigue life assessment to maintain its structural integrity. This methodology uses experimental flight data collected by airborne instrumentation systems. The recorded data are analysed for the prediction of the crack growth of defects at critical components of the aircraft and this information is then used for planning non‐destructive inspections, maintenance, logistical support and operational usage of the various fleets. This methodology is exemplified by one application on DASSAULT/DORNIER ALPHA‐JET aircraft. 相似文献
67.
Abstract The propagation of a television (TV) signal is usually perturbed during periods of atmospheric disturbance such as in thunderstorms. The region under investigation here is situated in the coastal area of the Bay of Bengal and has experienced frequent thunderstorm activities. An investigation to study their effects on VHF signal propagation transmitted from Satkhira in Bangladesh and received at the Indian Statistical Institute, Calcutta, has been undertaken. The depths of the atmospheric disturbances within a 1?km range have been recorded and measured by acoustic sounder (sodar) operated continuously at the receiving station. The inset of the storm is marked by the enhanced signal level with deep fluctuations characteristic during the periods of thunderstorms. 相似文献
68.
D. Van Oevelen F. DE L'Escaille H. Verachtert 《Journal of the Institute of Brewing》1976,82(6):322-326
Lambic is a type of Belgian beer obtained by spontaneous fermentation of wort. The fermentation in casks takes almost two years, and after that period the beer may be re-fermented in bottles and is then called gueuze. To gain insight into the many microbiological transformations occurring during this process, a qualitative and quantitative study of several components formed over a two-year period was undertaken. It was found that lambic and gueuze are characterized by high contents of ethyl acetate, ethyl lactate, lactic acid and acetic acid. Two phases of fermentation may be distinguished: a primary phase lasting for about three months during which almost all the ethanol and higher alcohols are formed and a very long secondary phase during which lactic acid is formed first, followed by ethyl lactate. Some lower fatty acids, including all the acetic acid, are made at the very beginning of the first phase. An important part of the ethyl acetate is made during the first phase but the amounts increase slowly to high levels during the second phase. Unusually low amounts of isoamyl acetate are detected. Several components are above the reported threshold levels of taste and are thus probably involved in the genesis of the typical aroma of lambic and gueuze. These results will allow a further study of the relations between the components found and the microbial populations involved in the spontaneous fermentation inherent in the brewing of lambic and gueuze. 相似文献
69.
Abstract In this article, we first point out the advantages and limitations of the keywords filtering techniques and the standard automatic clustering techniques for group technology applications. We consider, then, a product, or more generally an item, as a conjunction of symbolic attributes. We present a new method to recognize homogeneous families of products and to interpret the families by extraction of their concepts. Finally, the method is applied to analyze a population of 1010 mechanical parts. 相似文献
70.
M. DE LA SEN 《控制论与系统》2013,44(2-3):125-150
Abstract A perturbation theory for evaluation algorithms of arithmetic expressions is applied to the generalized least-squares identification of the continuous parameters by using nonperiodic discrete data. The sampling instants are distributed in such a way that a sequence of the elemental arithmetic expressions of the identification algorithm are suboptimized according to bang-bang rules on the extrema of appropriate variation intervals. The weighting scalars in the generalized least-squares method are updated with the same purpose. 相似文献