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101.
Adolescent development and public policy. 总被引:1,自引:0,他引:1
Emphasis by psychologists on the importance of early experience led policy makers in the 1960's and 1970's to concentrate public resources on compensatory educational programs for young, disadvantaged children. Research on the reversibility of early cognitive deficits and on the remediation of poor school achievement suggests that an expanded national investment in developing the cognitive competence of adolescents and young adults is warranted. Public policy should encourage schools, youth-serving agencies, business and industry, and the military to provide educational programs that stress general problem-solving abilities and basic academic skills alone. Demographic observations underscore the importance of such a policy for the strength of the nation. (3 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
S Diallo O Ndir Y Dieng FD Ba IB Bah BM Diop O Gaye T Dieng 《Canadian Metallurgical Quarterly》1995,40(2):123-128
One hundred ASA I orthopaedic surgical patients (four randomized groups) were anaesthetized using continuous propofol and intermittent fentanyl (TIVA), with controlled ventilation via a tracheal tube in groups 1 and 2, and a laryngeal mask airway (LMA) in groups 3 and 4. Neuromuscular blockers were used in groups 1 and 3 only. There were no significant differences between groups in total anaesthetic requirements, as assessed by cardiovascular variables and movement. Coughing interfered with surgery and made controlled ventilation difficult to manage. In contrast, movement not associated with coughing did not impair surgery or ventilation. Patients in group 2 (tracheal tube, no neuromuscular blocker) required more interventions for coughing than the other groups, while patients in group 4 (LMA, no neuromuscular blocker) needed more boluses for movement than groups 1 and 3. Groups 1 and 2 (tracheal tube) had significantly higher heart rates and mean arterial pressures than groups 3 and 4 for varying periods up to 5 min after insertion of the airway management device. There was no correlation between mean arterial pressure and plasma concentrations of catecholamines related to insertion of either the tracheal tube or LMA. The LMA was found to be a highly effective device for controlled ventilation in TIVA and easier to manage than the tracheal tube in the absence of neuromuscular blockers. 相似文献
103.
A rapid, simple method for the determination of lactose in milk or milk products is described. An internal standard (galactose) is added to the milk which is then extracted with carbon tetrachloride. A sample of the aqueous layer is injected onto a strongly acidic cation exchange column (Li+ form, 17 μm particles) and eluted with aqueous ethanol, the eluent composition being monitored with a modified moving-wire detector. Applications demonstrating the precision and accuracy of the method are described. 相似文献
104.
105.
Montague's difficult notation and complex model theory have tended to obscure potential insights for the computer scientist studying Natural Language. Despite his strict insistence on an abstract model-theoretic interpretation for his formalism, we feel that Montague's work can be related to procedural semantics in a fairly direct way. A simplified version of Montague's formalism is presented, and its key concepts are explicated in terms of computational analogues. Several examples are presented within Montague's formalism but with a view toward developing a procedural interpretation. We provide a natural translation from intensional logic into lisp. This allows one to express the composition of meaning in much the way Montague does, using subtle patterns of functional application to distribute the meanings of individual words throughout a sentence. The paper discusses some of the insights this research has yielded on knowledge representation and suggests some new ways of looking at intensionality, context, and expectation. 相似文献
106.
SM de Matta FD Monache F Ferrari GB Marini-Bettolo 《Canadian Metallurgical Quarterly》1976,31(7):527-535
The direct and indirect effects of staphylococcal enterotoxins A and C on the flux of water, sodium, and potassium have been studied in paired Thiry Vella fistulae in dogs. Administration of toxin resulted in a significant decrease in absorption, both in the loop to which the toxin had been administered and its pair. This decrease in absorption was associated with a decrease in movement out of the lumen, movement into the lumen remaining relatively unchanged. The mechanism of action of staphylococcal enterotoxins is discussed, and comparisons made with other enterotoxins. 相似文献
107.
108.
A filtration technique was employed to trap 14CO2 continuously for liquid scintillation counting. Devices for delivering scintillator and ethanolamine solutions were combined symmetrically with two fritted-glass aspirators for alternating operation. The collector was regulated by a fraction collector timer. Trial and animal tests indicated that the described method was efficient, reliable, and more convenient for frequent collection over long periods than alternative methods. The automatic collector was used for metabolic studies of [1-14C] arachidonic acid in rats kept in metabolic cages and the results were processed by multicompartmental analysis. 相似文献
109.
110.
This paper presents the results of a limited series of large scale in-line and bending fatigue tests on socketed structural strands typical of those used as stays for guyed masts and for suspension bridge hangers. The strand, consisting of a group of hard drawn galvanized steel wires laid up helically about a common axis, is terminated by zinc filled conical sockets. The various failure mechanisms, concentrated on the wires close to the socket, are described and discussed. It is concluded that conservative predictions of the in-line fatigue lives of real strands should be possible although further work is needed on bending fatigue. 相似文献