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51.
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Jonathan Cherneff Robert Logcher Jerome Connor Nicholas Patrikalakis 《Research in Engineering Design》1992,3(4):195-210
A method for machine interpretation of architectural (or other) schematic drawings is presented. The central problem is to build an efficient drawing parser (i.e., a program that identifies the semantic entities, characteristics, and relationships that are represented in the drawing). The parser is built from specifications of the drawing grammar and an underlying spatial model. The grammar describes what to look for, and the spatial model enables the parser to find it quickly. Coupled with existing optical recognition technology, this technique enables the use of drawings directly as: (1) a database to drive various Architecture-Engineering-Construction (AEC) applications; (2) a communication protocol to integrate CAD systems; (3) a traditional user interface. 相似文献
53.
H.‐G. Boyen G. Kstle K. Zürn T. Herzog F. Weigl P. Ziemann O. Mayer C. Jerome M. Mller J.P. Spatz M.G. Garnier P. Oelhafen 《Advanced functional materials》2003,13(5):359-364
Starting with Co‐salt‐loaded inverse micelles, which form if the diblock copolymer polystyrene‐block‐poly(2‐vinylpyridine) is dissolved in a selective solvent like toluene and CoCl2 is added to the solution, monomicellar arrays of such micelles exhibiting a significant hexagonal order can be prepared on top of various substrates with tailored intermicellar distances and structure heights. In order to remove the polymer matrix and to finally obtain arrays of pure Co nanoparticles, the micelles are first exposed to an oxygen plasma, followed by a treatment in a hydrogen plasma. Applying in‐situ X‐ray photoelectron spectroscopy, it is demonstrated that: 1) The oxygen plasma completely removes the polymer, though conserving the original order of the micellar array. Furthermore, the resulting nanoparticles are entirely oxidized with a chemical shift of the Co 2p3/2 line pointing to the formation of Co3O4. 2) By the subsequent hydrogen plasma treatment the nanoparticles are fully reduced to metallic Co. 3) By exposing the pure Co nanoparticles for 100 s to various oxygen partial pressures pequation/tex2gif-inf-5.gif, a stepwise oxidation is observed with a still metallic Co core surrounded by an oxide shell. The data allow the extraction of the thickness of the oxide shell as a function of the total exposure to oxygen (pequation/tex2gif-inf-7.gif × time), thus giving the opportunity to control the ferromagnetic–antiferromagnetic composition of an exchange‐biased magnetic system. 相似文献
54.
Genetic studies of the nematode Caenorhabditis elegans have defined a variety of single-gene mutations that have specific effects on programmed cell death. Analyses of the genes defined by these mutations have revealed that cell death is an active process that requires gene function in cells that die. Specific genes are required not only to cause cell death but also to protect cells from dying. Gene interaction studies have defined a genetic pathway for the execution phase of programmed cell death in C. elegans. Molecular and biochemical findings are consistent with the pathway proposed from these genetic studies and have also revealed that the protein products of certain cell-death genes interact directly. This pathway appears to be conserved among organisms as diverse as nematodes and humans. Important questions remain to be answered about programmed cell death in C. elegans. For example, how does a cell decide to die? How is cell death initiated? What are the mechanisms of action of the cell-death protector and killer genes? What genes lie downstream of the cell-death execution pathway? The conservation of the central cell-death pathway suggests that additional genetic analyses of programmed cell death in C. elegans will help answer these questions, not only for this nematode but also for other organisms, including ourselves. 相似文献
55.
Discontinuation of positive pressure mechanical ventilation results in decreased intrathoracic pressure. Although there has been extensive research into factors associated with weaning adults from mechanical ventilatory support, little attention has been paid to the role of left ventricular performance. Research also has not focused on interventions that might optimize ventricular performance. The purpose of this article is to explore the potential effect of cardiac dysfunction in weaning and the role of drug chronotherapy as a strategy to modify patients' responses to weaning from mechanical ventilatory support. Biophysical principles involved are reviewed, and the development of a chronotherapeutic intervention is described. Two case examples illustrate the use of drug chronotherapy during the weaning process. 相似文献
56.
Levitt Mary J.; Guacci-Franco Nathalie; Levitt Jerome L. 《Canadian Metallurgical Quarterly》1993,29(5):811
Little is known about social networks in childhood, and even less is known about the networks of ethnically diverse children. Interviews were conducted with 333 African-American, Anglo/European-American, and Hispanic-American public school children in Grades 1–2, 4–5, and 8–9. The research was based on the social convoy model (R. L. Kahn and T. C. Antonucci, 1980), in which social networks are viewed as dynamic hierarchic structures affording the provision of support across the life span. An adapted convoy mapping procedure evidenced good test–retest reliability at all ages, and convoy support measures were associated with self-concept and teacher-rated sociability and mood. For all ethnic groups, the results reflect the significance of close family relations across age, an increase in involvement with extended family in middle-childhood, and the emergent role of peers as support providers in adolescence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Isolation of porcine circovirus-like viruses from pigs with a wasting disease in the USA and Europe 总被引:3,自引:0,他引:3
GM Allan F McNeilly S Kennedy B Daft EG Clarke JA Ellis DM Haines BM Meehan BM Adair 《Canadian Metallurgical Quarterly》1998,10(1):3-10
Sinus pericranii is an anomalous extracranial vascular malformation that is in continuity with the intracranial dural venous sinuses. Five case reports, three congenital and two traumatic, are described. Clinical management, including evaluation, diagnosis, and treatment, is discussed. Awareness of this entity by plastic surgeons will allow for earlier diagnosis and appropriate surgical management, resulting in decreased risk of complications. 相似文献
58.
59.
A Mitchener DJ Wyper J Patterson DM Hadley JT Wilson LC Scott M Jones GM Teasdale 《Canadian Metallurgical Quarterly》1997,62(6):633-636
We report a case of cervicofacial necrotizing fasciitis that developed after blepharoplasty, an occurrence that, to our knowledge, has not previously been reported in the medical literature. A patient who presented to our institution 3 days after undergoing blepharoplasty of the upper eyelid was diagnosed as having fulminant fasciitis involving extensive areas of the face, scalp, and neck. We review the case in detail and discuss clinical and radiological clues to diagnosis, surgical and medical management, wound care, and subsequent scar contracture. This case emphasizes the need for individualized, appropriate postoperative care and for an awareness of this rare, potentially fatal complication. Early recognition and aggressive treatment of cervicofacial fasciitis can arrest its rapid progression and prevent devastating sequelae. 相似文献
60.
JA Zaia GM Gallez-Hawkins BR Tegtmeier A ter Veer X Li JC Niland SJ Forman 《Canadian Metallurgical Quarterly》1997,176(3):782-785
Late occurrence of cytomegalovirus (CMV) disease after day 100 after bone marrow transplantation has become an increasing problem; whether a quantitative measurement of CMV DNA in plasma by polymerase chain reaction (P-PCR) could be predictive of such disease was investigated. In a prospective study, 117 subjects undergoing allogeneic marrow transplantation were followed for 120 days with weekly CMV blood cultures, with day 35 bronchoalveolar lavage CMV cultures, with weekly CMV P-PCR, and with clinical follow-up for an additional 1-2 years. Despite preemptive ganciclovir, CMV disease occurred in 9% of subjects, with a median time of onset of 176 days. Quantitative CMV P-PCR was associated with the late development of CMV disease (P = .01). Of 43 subjects with positive P-PCR results, 23% developed CMV disease, but no disease occurred in the 74 subjects with negative P-PCR (P < .001), despite the fact that 22% had CMV isolated from lung lavage fluid and 32% had CMV isolated from blood. 相似文献