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1.
The authors argued that AI systems must be able to manipulate their own internal representations automatically to deal with an infinitely complex and ever-changing world and to scale up to rich, complex applications. Such manipulation must go beyond changing beliefs and learning new concepts in terms of old concepts; it must be able to change ontology's underlying syntax and semantics. Initial progress has been made, but further progress is urgently needed owing to the demands of autonomous multiagent systems. Understanding and implementing this ability must be a major focus of AI for the next 50 years. 相似文献
2.
The possibility that progesterone or estradiol may regulate expression of G protein in the rat myometrium during the course of pregnancy has been investigated using 1) immunoblot analysis of Gi2 alpha, Gi3 alpha, and Gq alpha subunits and 2) hybridization blot analysis of subunit mRNA. Eighteen hours after administration, estradiol had significantly increased the levels of both Gi2 alpha subunit and Gi2 alpha mRNA (by 40% and 32%, respectively). In control pregnant rats, we observed similar changes at the end of pregnancy, when myometrial concentrations of estradiol had increased, i.e., a 41% increase in immunoreactive Gi2 alpha subunit that correlated with a parallel 45% increase in mRNA levels. In contrast, levels of immunoreactive Gi3 alpha subunit and mRNA, which decreased with advancing gestation, were not influenced by estradiol or progesterone administration. Progesterone administration resulted 30 h later in a significantly decreased level of Gq alpha immunoreactivity (32%) and Gq alpha mRNA (30%). In control rats, Gq alpha protein and mRNA were also significantly lower at midpregnancy under progesterone dominance vs. term. At this stage, a twofold increase in Gq alpha subunit correlated with a 40% increase in mRNA levels. These results demonstrate that myometrial Gi2 alpha and Gq alpha subunits are physiological targets for estradiol and progesterone, respectively, in vivo. Alterations of these G protein levels are discussed in relation to their mediating effects on adenylyl cyclase activity or the phospholipase C pathway during the course of pregnancy. 相似文献
3.
An introduction to parallel process interventions is provided by a comprehensive review of the theoretical constructs and empirical studies regarding the use of the parallel process in supervision. Although more direct investigations of the parallel process are needed, we conclude that parallel process interventions within the supervisory relationship can be extremely potent and impactful. Recommendations for the facilitative application of the parallel process in the supervision and training of professional psychologists, as well as case examples, are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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5.
MS McNeill DB Griffin TR Dockerty JP Walter HK Johnson JW Savell 《Canadian Metallurgical Quarterly》1998,76(6):1613-1620
Twenty-nine selected styles of subprimals or sections of veal were obtained from a commercial facility to assist in the development of a support program for retailers. They were fabricated into bone-in or boneless retail cuts and associated components by trained meat cutters. Each style selected (n = 6) was used to generate mean retail yields and labor requirements, which were calculated from wholesale and retail weights and processing times. Means and standard errors for veal ribs consisting of five different styles (n = 30) concluded that style #2, 7-rib 4 (10 cm) x 4 (10 cm), had the lowest percentage of total retail yield (P < .05) owing to the greatest percentage of bone. Furthermore, rib style #2 required the longest total processing time (P < .05). Rib styles #3, 7-rib chop-ready, and #5, 6-rib chop ready, yielded the greatest percentage of total retail yield and also had the shortest total processing time (P < .05). Within veal loins, style #2, 4 (10 cm) x 4 (10 cm) loin kidney fat in, had the greatest percentage fat (P < .05). Loin styles #2 and #3, 4 (10 cm) x 4 (10 cm) loin special trimmed, generated more lean and fat trimmings and bone, resulting in lower percentage of total retail yields than loin style #1, 0 (0 cm) x 1 (2.5 cm) loin special trimmed (P < .05). Results indicated that bone-in subprimals and sections required more processing time if fabricated into a boneless end point. In addition, as the number of different retail cuts increased, processing times also increased. 相似文献
6.
Gerald P. McNeill Philip E. Sonnet 《Journal of the American Oil Chemists' Society》1995,72(2):213-218
Three lipases were compared for their ability to hydrolyze high erucic acid rapeseed oil, with the objective of concentrating
the erucic acid in a single glyceride fraction. Lipase fromPseudomonas cepacia released all fatty acids rapidly and did not result in selective distribution of erucic acid.Geotrichum candidum lipase released C20 and C22 fatty acids extremely slowly, resulting in their accumulation in the di- and triglyceride fractions.
Less than 2% of the total erucic acid was found in the free fatty acid (FFA) fraction. Lipase fromCandida rugosa released erucic acid more slowly than C20 and C18 fatty acids at 35°C but only resulted in a limited accumulation of the
erucic acid in the di- and triglyceride fractions. However, when hydrolysis catalyzed byC. rugosa lipase was carried out below 20°C, the reaction mixture solidified and was composed solely of FFAs and diglycerides. The
diglyceride fraction contained approximately 95% erucic acid while about 20% of the total erucic acid was found in the FFA
fraction. It is concluded that hydrolysis at low temperature withC. rugosa lipase results in a higher purity of erucic acid in the glyceride fraction than can be obtained withG. candidum lipase, but with considerable loss of erucic acid to the FFA fraction. 相似文献
7.
The Employee Health Care Value Survey: round one 总被引:1,自引:0,他引:1
In a groundbreaking arrangement, a consortium of large employers--the Xerox, GTE, and Digital Equipment Corporations--launched the Employee Health Care Value Survey during fall 1993. Completed by 24,306 employees, this survey was used to develop comparable methods for assessing corporate health care benefit strategies. It also enabled fair comparisons of thirty-two health plans across the country on more than sixty criteria. Variation in performance among plans was substantial, with managed care plans--particularly prepaid group practices and individual practice associations (IPAs)--recording the most favorable rankings on disenrollment, overall satisfaction, and other measures of "bottom-line performance." Variation in enrollees' health among plans was more modest, with indemnity enrollees posing a somewhat greater illness burden to their plans than enrollees of other plan types. The employers and evaluated health plans are now using the results for multiple purposes, including quality improvement initiatives, employee-based plan performance reports, employee contribution strategies, and health promotion programs. 相似文献
8.
We study how Gaussian laser-beam profiles can be modified into a desired form using acousto-optic Bragg diffraction. By exploiting the angular dependence of Bragg diffraction of plane waves by acoustic gratings, we demonstrate that the conversion from a Gaussian-profile beam into either a near-field or a far-field flattop profile is possible. 相似文献
9.
GE Kwan Lim L McNeill K Whitley DL Becker R Zamoyska 《Canadian Metallurgical Quarterly》1998,28(2):745-754
A reaction-diffusion model was developed to predict the fate of nitric oxide (NO) released by cells of the immune system. The model was used to analyze data obtained previously using macrophages attached to microcarrier beads suspended in a stirred vessel. Activated macrophages synthesize NO, which is oxidized in the culture medium by molecular oxygen and superoxide (O2-, also released by the cells), yielding mainly nitrite (NO2-) and nitrate (NO3-) as the respective end products. In the analysis the reactor was divided into a "stagnant film" with position-dependent concentrations adjacent to a representative carrier bead and a well-mixed bulk solution. It was found that the concentration of NO was relatively uniform in the film. In contrast, essentially all of the O2- was calculated to be consumed within approximately 2 microm of the cell surfaces, due to its reaction with NO to yield peroxynitrite. The decomposition of peroxynitrite caused its concentration to fall to nearly zero over a distance of approximately 30 microm from the cells. Although the film regions (which had an effective thickness of 63 microm) comprised just 2% of the reactor volume and were predicted to account for only 6% of the NO2- formation under control conditions, they were calculated to be responsible for 99% of the NO3- formation. Superoxide dismutase in the medium (at 3.2 microM) was predicted to lower the ratio of NO3- to NO2- formation rates from near unity to <0.5, in reasonable agreement with the data. The NO3-/NO2- ratio was predicted to vary exponentially with the ratio of O2- to NO release rates from the cells. Recently reported reactions involving CO2 and bicarbonate were found to have important effects on the concentrations of peroxynitrite and nitrous anhydride, two of the compounds that have been implicated in NO cytotoxicity and mutagenesis. 相似文献
10.
Bruce G. Cameron Edward F. Crawley Jakub Kwapisz Alicia McNeill 《Engineering Management Journal; EMJ》2017,29(3):128-139
Platforming has become an important means of cost-sharing among industrial products. However, many firms face systemic downward pressure on commonality, with the result that many platforms realize less commonality than intended. Past research has hypothesized that divergence is the result of conflicting tensions between product customization/optimization and cost control. This article investigates the control and incentive levers available to platform managers to shape the behavior of the organization when divergence opportunities arise. Management levers are drawn from a series of 12 industrial case studies, stemming from investigations of the causes of divergences. These management levers are categorized as technical levers, financial levers, and organizational levers. This article illustrates each of the management levers with examples from the case studies. 相似文献