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71.
Begg Ian; Snider Andrea; Foley Finola; Goddard Robert 《Canadian Metallurgical Quarterly》1989,15(5):977
The generation effect occurs if people remember items they complete from fragments better than complete items they read. Four experiments investigate two questions. When does the effect occur, and why does it do so? Targets generated in related contexts are recognized better than read targets, and they are recalled better with the contexts as cues; the contexts are recognized equally well, and the relation between the context and target is not enhanced by generation. Furthermore, generated items exceed items read in pure lists even when read ones from the mixed list are no worse than the controls. The generation effect is real; it is not an artifact. However, there is nothing special about generation. Generating is a type of encoding, and like any other type of encoding, its effects are maximal on tests that require subjects to do again whatever they did at study. Generating makes targets distinctive by contrasting them with other relatives of the context, and, as a result, the targets enjoy benefits in later discriminations within their family. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
The gates of GaAs MESFETS rely on the formation of a Schottky diode between the semiconductor surface and a deposited metal and so are extremely sensitive to the nature of this interface. For this reason an investigation of surface damage and contamination by the various processing stages involved in IC fabrication has been undertaken. This paper outlines the results obtained from processes involved in activation of ion implantation through annealing with a dielectric encapsulant, wet chemical etching, and metallization. Methods for removing or minimizing the effects of processing damage or contamination are also investigated. 相似文献
73.
Objective: Guided by the extended parallel process model (EPPM), the objective was to assess control processes dominant in influenza behavior decisions. Design: Cross-sectional survey. Results: Response rate was 31% (n=968). Regarding influenza risk, 59% were in danger control. Those in fear control were more likely to report influenza infection (p=.000). In the nonvaccinated, those in fear control were more likely to indicate not knowing where to get the vaccine (p=.016) and that it was unavailable (p=.027), and those in danger control believed they did not need it (p=.023). Zero critical values were more likely to indicate that no health provider recommended the shot (p=.002). Conclusions: Most perceived efficacy to be stronger than threat related to influenza; according to the EPPM, they are aware of their risk but recognize their ability to avert it. For those in danger control, messages should focus on increasing perceptions of severity and susceptibility to positively affect behavior change. For those in fear control, messages should focus on efficacy only. With a critical value of zero, no threat is induced, and a high-threat/high-efficacy approach should be taken. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
The total syntheses of 9(Z),12(E)- and 9(E),12(Z)-octadecadienoic acids have been carried out. A useful intermediate in both
syntheses, 8-bromo-octanoic acid, recently has become available from commercial sources. This compound has been used to expedite
the preparation of these isomers. The remaining carbon atoms were derived from propargyl alcohol along with either 1-heptyne
or acetylene and 1-bromopentane. Because the overall yield for each sequence was roughly 15% and there were no extraordinary
reaction conditions in any of the synthetic steps, the compounds could be prepared readily in multiple gram quantities. The
syntheses of the two compounds were supported by data from a variety of spectroscopic techniques. 相似文献
75.
V. Elliott Smith John M. Spurr John C. Filkins Jody J. Jones 《Journal of Great Lakes research》1985,11(3):231-246
Organochlorine analysis was performed on carcasses of 13 diving ducks from a 1981 wintering population that foraged on contaminated sediments in the lower Detroit River. Mean total PCB concentrations were 10 mg/kg for seven lesser scaups (Aythya affinis), 11 mg/kg for three greater scaups (A. marila), and 7.6 mg/kg for three goldeneyes (Bucephala clangula). Highest mean levels of other residues were measured for hexachlorobenzene (1.7 mg/kg) in goldeneyes, and transnonachlor (0.33 mg/kg) and 4,4’-DDE (1.3 mg/kg) in greater scaup. Quantitative analysis of 72 PCB congeners also was applied to water, seston, sediment, benthie oligochaetes, and carp from the same site. Principal congeners in most of the samples included some of the more toxic and persistent PCBs. Results of a multivariate analysis indicated that ratios of more conservative to less conservative PCBs did not vary significantly among ducks (α = .05), but differed from those in carp, oligochaetes, and sediment. For the February through March period of fat mobilization, concentrations of total PCB in lipid were inversely correlated with percent lipid (r = 0.76) in ducks. The percentage of conservative PCBs increased slightly. The distribution and partitioning of organochlorines, including toxic PCB congeners, varied considerably within this water column-sediment-fauna ecosystem. Estimates of toxic exposure based on total PCB values may be unreliable. 相似文献
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79.
Makris Angela P.; Rush Craig R.; Frederich Robert C.; Taylor Alisia C.; Kelly Thomas H. 《Canadian Metallurgical Quarterly》2007,15(2):123
Modafinil is indicated for the management of excessive daytime sleepiness; however, recent studies have examined a broad range of potential uses. Given that clinical uses of modafinil may be expanding, this study compared modafinil and d-amphetamine effects on subjective and performance measures. Across 11 sessions, 11 healthy adults were tested after oral doses of placebo (5 sessions), modafinil (1.75 mg/kg, 3.50 mg/kg, or 7.00 mg/kg), and d-amphetamine (0.035 mg/kg, 0.070 mg/kg, 0.140 mg/kg) under double-blind, randomized conditions. Assessments of cognitive performance and subjective effects were completed before drug administration, 30 min after drug administration, and at hourly intervals after drug administration for 5 hr. Modafinil increased ratings on the Amphetamine and Morphine Benzedrine Group scales of the Addiction Research Center Inventory (ARCI) and increased ratings on the Vigor and Total Positive scales of the Profile of Mood States. d-Amphetamine increased visual analog ratings of feeling stimulated and liking the drug and increased ratings on the Morphine Benzedrine Group scale of the ARCI. Both medications significantly reduced visual analog scale ratings of feeling sleepy, and modafinil decreased ratings on the ARCI Pentobarbital-Chlorpromazine-Alcohol Group scale. Both medications sustained performance that deteriorated across time on the Sternberg Number Recognition Test. Modafinil also enhanced performance rate on the Digit-Symbol Substitution Task above baseline levels and increased response rate on the Repeated Acquisition of Response Sequences Task. These results suggest that modafinil engenders alerting effects and increases performance in healthy non-sleep-deprived individuals comparable with that of d-amphetamine. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
The authors present a theory for understanding risk for problem drinking among reservation-dwelling American Indians. The theory offers an overall framework for understanding the risk process for this group. It considers the distinction between factors that influence mean levels of American Indian problem drinking and factors that influence individual differences in American Indian drinking. It proposes important contextual differences between reservation-dwelling American Indians and Caucasians that may help explain the higher mean levels of American Indian problem drinking. The theory further holds that, within the high mean level of problem drinking characteristic of many American Indian reservations, individual differences in problem drinking can be explained by very similar personality and learning factors as those that influence problem-drinking levels for other ethnic groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献