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71.
72.
KJ Clark AB Sarr PG Grant TD Phillips GN Woode 《Canadian Metallurgical Quarterly》1998,63(2-4):137-146
Rotaviruses are the leading cause and coronaviruses are the major contributors of acute gastroenteritis in the young of various mammalian and avian species. Despite numerous trials and decades of research, vaccines have limited efficacy particularly for calves. As an alternative method of controlling infection, we have investigated broad spectrum antiviral agents that are not discriminatory among various viruses. This report involves testing a variety of adsorbent agents including charcoal, clay, and clay minerals to adsorb rotavirus and coronavirus in vitro. Results revealed that all the adsorbent agents had good to excellent capability of adsorbing rotavirus and excellent capability of adsorbing coronavirus. Percent adsorptions ranged from 78.74% to 99.89% for rotavirus and 99.99% for coronavirus; while sand (negative control) was < 0.01%. A high affinity binding was present as determined by a low percent desorption (0.06-3.09%). However, the adsorbent bound virus complex retained, and may have actually enhanced, infectivity. 相似文献
73.
During a flight over sea, the right-hand trailing-edge flap (TEF) from an RAAF F/A-18 separated. Although the flap was not recovered, the mode of failure suggested that the outboard hinge lug was first to fail. A fleet-wide inspection of the TEF outer hinge lugs disclosed two other cracked hinge lugs. Examination of these cracks revealed that they had propagated as the result of a combination of corrosion and fatigue, in that the corrosive environment appeared to have accelerated the fatigue crack growth rate. Laboratory experiments indicated that, in a salt solution, the 7050 aluminium alloy from which the lugs were manufactured is susceptible to corrosion fatigue and that the observed cracking matched that on the cracked lugs: corrosion fatigue was therefore suspected to have been a contributing factor in the unexpected failure. Quantitative fractography on the fatigue cracks, combined with several assumptions and deductions, including information about the failure size of the crack gained from witness marks found on the monoball bearing of the failed TEF, led to an estimate of the fatigue crack growth rate. This crack growth rate and the short service life clearly indicated the limitations of the then-current non-destructive inspection (NDI) technique, and a more sensitive inspection method was developed to assist in the maintenance of adequate RAAF flying hours between inspections. This failure investigation provided an excellent example of how fractography, laboratory experiments and NDI can be combined to determine a possible cause of failure and to establish remedial measures for the fleet. 相似文献
74.
Krick R.F. Clark L.T. Deleganes D.J. Wong K.L. Fernando R. Debnath G. Banik J. 《Solid-State Circuits, IEEE Journal of》1994,29(12):1455-1463
An implementation of the Pentium microprocessor architecture in 0.6 μm BiCMOS technology is described. Power dissipation is reduced and performance is enhanced over the previous generation. Processor features, implementation technology, and circuit techniques are discussed. An internal clock rate of 150 MHz is achieved at 3.7 V and -55°C 相似文献
75.
76.
Blanchard Edward B.; Appelbaum Kenneth A.; Guarnieri Patricia; Neff Debra F.; Andrasik Frank; Jaccard James; Barron Kevin D. 《Canadian Metallurgical Quarterly》1988,56(3):427
Tension and vascular headache patients, initially treated with biofeedback and/or relaxation training in either a minimal therapist contact protocol (3 visits) or an intensive individual protocol (10 or 16 visits) were followed-up prospectively for 2 years. In the first study, for the first 6 months of follow-up, half of all patients continued to keep headache diaries and were seen monthly and the other half had only minimal contact. The results at 1-year follow-up, based on 4 weeks of daily headache diaries, revealed equally good maintenance from both treatment protocols and from both follow-up conditions. In Study 2, we found that patients remained improved over pretreatment baseline levels at the 2-year follow-up regardless of initial treatment intensity. Approximately three quarters of vascular patients who were initially improved at posttreatment remained improved at 2 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Regression analyses of counts and rates: Poisson, overdispersed Poisson, and negative binomial models. 总被引:1,自引:0,他引:1
The regression models appropriate for counted data have seen little use in psychology. This article describes problems that occur when ordinary linear regression is used to analyze count data and presents 3 alternative regression models. The simplest, the Poisson regression model, is likely to be misleading unless restrictive assumptions are met because individual counts are usually more variable ("overdispersed") than is implied by the model. This model can be modified in 2 ways to accommodate this problem. In the overdispersed model, a factor can be estimated that corrects the regression model's inferential statistics. In the second alternative, the negative binomial regression model, a random term reflecting unexplained between-subject differences is included in the regression model. The authors compare the advantages of these approaches. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Discusses the mental health problems that may occur as elderly people must face adjustments because of bereavement, poor physical health, the demands of caring for an ill spouse, drug/alcohol abuse, dementia and cognitive impairments, and multiple health problems. Negative social stereotypes associated with both elderly patients and mental health care, limited access to and a lack of trained professionals in the area of geriatric mental health care, lack of outreach, inadequate benefits under prepaid health plans, Medicare and Medicaid, and special problems of ethnic minority and rural elderly people all contribute to an inadequate mental health care system. The author, a US representative, suggests a redesigning of the system and outlines an initiative that addresses the development of an effective mental health care system for the elderly, modification of Medicare and Medicaid, and improvements in quality assurance and access protection. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
94 smokers (mean age 39 yrs) in a 6-wk behavioral smoking-cessation program were administered weekly questionnaires on their use of major program recommendations and other quitting strategies throughout treatment. An "affect-regulation" coping inventory was administered at the beginning and end of treatment. Adequate adherence was reported for most recommendations. Although a composite measure of adherence did not predict quitting success, adherence and coping assessments were associated with maintenance of treatment gains. Short-term maintenance was associated with an extensive affect-regulation repertoire and use of stimulus control strategies; long-term maintenance was associated with consistent self-monitoring of smoking during treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
The hierarchies of knowledge and the mathematics of discovery 总被引:1,自引:1,他引:0
Clark Glymour 《Minds and Machines》1991,1(1):75-95
Rather than attempting to characterize a relation of confirmation between evidence and theory, epistemology might better consider which methods of forming conjectures from evidence, or of altering beliefs in the light of evidence, are most reliable for getting to the truth. A logical framework for such a study was constructed in the early 1960s by E. Mark Gold and Hilary Putnam. This essay describes some of the results that have been obtained in that framework and their significance for philosophy of science, artificial intelligence, and for normative epistemology when truth is relative.I am indebted to Kevin Kelly for several years of happy conversation from which the perspective and views of this paper grew, for comments on a draft of the paper, and for constructing some of the illustrations. A fellowship from the John Simon Guggenheim Memorial Foundation provided the liberty to write this paper. It was first presented in the Turing Colloquium, 1990. 相似文献