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171.
Robert G. Franke 《Zygon》1984,19(1):29-41
Abstract. Loren Eiseley is known both as a scientist and an essayist/poet. The disillusionment with science and technology among many in the late 1950s and the search for new values in the 1960s help account for Eiseley's significance as a writer. He appears to offer a solution to mankind's contemporary disillusionment by reminding that science has limits and that intuitive, nonscientific insight is valid, especially when it is complementary to scientific knowledge. The thesis of this essay is that in content and style Eiseley writes as a religious writer in the sense that he reaffirms what is necessary for humankind to be happy and even to be "saved." 相似文献
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The influence of contextual stimuli on the conditioning and performance of responding to a discrete stimulus was examined in the US preexposure paradigm using both context shift manipulations and a measure of context conditioning. Four groups of rats received both repeated exposure to an electric shock US in one context (Context 1), and repeated nonshocked exposure to a second context (Context 2). Two additional groups of rats received exposure to these contexts, but never received shock presentations. Rats exposed to shock learned to escape from the stimuli of Context 1, but did not escape from the stimuli provided by Context 2. Rats not exposed to shock failed to escape from either context. All rats then received a single CER conditioning session in which four pairings of a 3-min noise CS and shock US were presented. Half the rats received those CS-US pairings in the excitatory Context 1, while the remaining rats received those pairings in the neutral Context 2. Finally, half the rats in each of the CER conditioning treatments received extinction test trials of the noise CS in Context 1, while the remaining rats received those test trials in Context 2. Thus, this design factorially manipulated the presence of excitatory or neutral contextual stimuli during both conditioning and testing of a discrete CS. In comparison with the two groups of rats never preexposed to shock alone, attenuation in acquisition of conditioned suppression observed during test trials occurred only when CER conditioning had been administered in the excitatory Context 1, and this effect was manifested when testing occurred in either the excitatory Context 1 or the neutral Context 2. These results support the model of R. A. Rescorla and A. R. Wagner (1972) (in A. H. Black & W. F. Prokasy (Eds.) Classical Conditioning II, pp. 64–99, New York: Appleton-Century-Crofts) which asserts that contextual stimuli and sicrete CSs compete for limited associative strength supportable by a given US. 相似文献
174.
Three experiments investigating the effects of arousal on the T-maze choice behavior of inbred mouse strains are reported. In Experiment 1, CBA and NZB mice were administered unrewarded free choice alternation tests on 10 consecutive days under either No Shock, Shock Start (shocked in the start box), or Shock Choice (shocked at the choice point) treatment conditions. Both strain and treatment effects were observed: In the No-Shock condition, the nonreactive CBA strain alternated, but the reactive NZB strain did not. In the Shock Start condition the CBA strain showed only a suppressed alternation, while the NZB strain administered the same treatment perseverated. Both strains perseverated in the Shock Choice condition. In Experiment 2, NZB mice administered identical shocks in the start box and goal arms on both trials of five consecutive tests conducted once a day perseverated to the same goal arm in which they had been shocked on the first trial. In Experiment 3, NZB mice punished for perseverating (with shock continuation) and simultaneously reinforced for alternating (with shock termination) showed a “punishment paradox”; they perseverated despite the reinforcement contingencies. These results, which are congruent with the optimal arousal theory and several characteristics the theory shares with the emergent neophobia construct, support the contention that arousal mediates a symmetrical relationship between approach and avoidance along a novelty-familiarity continuum. 相似文献
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176.
Children and their families have been significantly impacted by the unfolding of the COVID-19 syndemic. We sought to identify (1) groups of families with distinct profiles of joint trajectories of parental anxiety and child emotional distress and (2) protective and risk factors associated with these dual-trajectory profiles. A sample of 488 parents (65% White; 77% mothers) with 3- to 8-year-old children (MAge = 5.04, SDAge = 1.59) was followed from late March to early July in 2020. Survey data on parent (i.e., anxiety symptoms) and child (i.e., emotional distress) adjustment were collected at three time points. Using multivariate growth mixture modeling, we identified one group with low parental anxiety and child emotional distress (42.7%) and three other distinct groups with varying risk levels among parents and/or children. We also identified protective (e.g., positive parenting) and risk (e.g., child negative affect, negative parenting, perceived stress with racism) factors in predicting parent and child adjustment. It can be concluded that, overall, our sample (mostly middle- and high-socioeconomic status families) demonstrated family resilience amid COVID-19, consistent with prior disaster coping literature. At the same time, our findings also indicated the need to identify at-risk families and modifiable factors for post-disaster public health interventions. 相似文献
177.
We can use radically different reference-schemes to generate the same truth-conditions for the sentences of a language. In this paper, we do three things. (1) Distinguish two arguments that deploy this observation to derive different conclusions. The first argues that reference is radically indeterminate: there is no fact of the matter what ordinary terms refer to. This threat is taken seriously and most contemporary metasemantic theories come with resources intended to rebut it. The second argues for radical parochialism about reference: it's a reflection of our parochial interests, rather than the nature of the subject matter, that our theorizing about language appeals to reference rather than another relation that generates the same truth-conditions. Rebuttals of the first argument cut no ice against the second, because radical parochialism is compatible with reference being determinate. (2) Argue that radical parochialism, like radical indeterminacy, would be shocking if true. (3) Argue that the case for radical parochialism turns on the explanatory purposes of “reference”-talk: on relatively “thin” conceptions, the argument goes through, and radical parochialism is (shockingly!) true; on richer conceptions, the argument can be blocked. We conclude that non-revisionists must endorse, and justify, a relatively rich conception of the explanatory purposes of “reference”-talk. 相似文献
178.
Animal Cognition - There is substantial evidence of group-specific behaviors in wild animals that are thought to be socially transmitted. Yet experimental studies with monkeys have reported... 相似文献
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180.
A study and replication of students faking interest in high status occupations on the Strong Vocational Interest Blank for Men. In general, the faking was successful in shifting the specific target occupational scales and especially the occupational level scale. Other scales are affected, many with decisive upward or downward shifts. Demonstration is made of the extent to which the faking condition led to differences in the overall test results. Various aspects of the general problem of test faking are reviewed. 相似文献