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251.
Social Psychology of Education - The current study examined the relationship of academic entitlement with student attitudes (e.g., locus of control, motivation) and academic behavior. Participants...  相似文献   
252.
To gain a better understanding of the evolution of animal cognition, it is necessary to test and compare the cognitive abilities of a broad array of taxa. Meaningful inter-species comparisons are best achieved by employing universal paradigms that standardize testing among species. Many cognitive paradigms, however, have been tested in only a few taxa, mostly birds and primates. One such example, known as the Aesop’s Fable paradigm, is designed to assess causal understanding in animals using water displacement. To evaluate the universal effectiveness of the Aesop’s Fable paradigm, we applied this paradigm to a previously untested taxon, the raccoon (Procyon lotor). We first trained captive raccoons to drop stones into a tube of water to retrieve a floating food reward. Next, we presented successful raccoons with objects that differed in the amount of water they displaced to determine whether raccoons could select the most functional option. Raccoons performed differently than corvids and human children did in previous studies of Aesop’s Fable, and we found raccoons to be innovative in many aspects of this task. We suggest that raccoon performance in this paradigm reflected differences in tangential factors, such as behavior, morphology, and testing procedures, rather than cognitive deficiencies. We also present insight into previously undocumented challenges that should better inform future Aesop’s Fable studies incorporating more diverse taxa.  相似文献   
253.
Spontaneous speech acoustics are highly variable. Such variability may be problematic for infants relying on phonological form to solve the segmentation problem. In the present study, acoustic measures of vowel duration and a computer model of speech segmentation were used to evaluate the problem of phonetic variability for a rhythm-based speech segmentation strategy. The specific questions under study were (1) whether or not mothers realized disyllabic vowel duration patterns consistently in spontaneous infant-directed speech, and (2) whether or not these patterns were distinctive enough in the context of an utterance to provide a useful cue for speech segmentation. Data from four English-speaking mothers indicated that the trochaic-like duration pattern may interact with phrase-position and with grammatical category, but when the resulting patterns are consistent, they provide useful segmentation cues for spontaneous infant-directed speech.  相似文献   
254.
It is a guilty secret that many college professors sell the complimentary desk copies that they receive from textbook publishers for cash. This article attempts to shed light on the undercover practice by looking at the resale of complimentary textbooks by faculty from four perspectives. Part One provides an overview of the college textbook industry, the business reasons that motivate publishers to provide complimentary desk copies to faculty, and the economic consequences of the entry of the textbooks into the used book market. Part Two examines the legal characteristics of complimentary desk copies in terms of their ownership and any contractual duties that may arise from their receipt. Part Three looks at legislative efforts to curb the practice, and Part Four reviews university policies addressing the issue. In Part Five, the ethical implications of faculty selling desk copies are examined, with a special focus on this practice in a business school. The Conclusion considers the future of the sale of complimentary copies in light of the move to e-books and other initiatives by authors and textbook publishers to circumvent the practice.  相似文献   
255.
We reply to the Ioannidis's paper "Effectiveness of antidepressants; an evidence based myth constructed from a thousand controlled trials." We disagree that antidepressants have no greater efficacy than placebo. We present the efficacy from hundreds of trials in terms of the percentage of patients with a substantial clinical response (a 50% improvement or more symptomatic reduction). This meta-analysis finds that 42-70% of depressed patients improve with drug and 21%-39% improve with placebo. The response benefit of antidepressant treatment is 33%-11% greater than placebo. Ioannidis argues that it would be vanishingly smaller because systematic biasing in these clinical trials would reduce the drug-placebo difference to zero. Ioannidis' argument that antidepressants have no benefit is eroded by his failures of logic because he does not present any evidence that there are a large number of studies where placebo is substantially more effective than drug. (To reduce to zero, one would also have to show that some of the unpublished studies find placebo better than drug and have substantial systematic or methodological bias). We also present the empirical evidence showing that these methodological concerns generally have the opposite effect of what Ioannidis argues, supporting our contention that the measured efficacy of antidepressants likely underestimates true efficacy. Our most important criticism is Ioannidis’ basic underlying argument about antidepressants that if the existing evidence is imperfect and methods can be criticized, then this proves that antidepressant are not efficacious. He presents no credible evidence that antidepressants have zero effect size. Valid arguments can point out difficulties with the data but do not prove that a given drug had no efficacy. Indeed better evidence might prove it was more efficacious that originally found. We find no empirical or ethical reason why psychiatrists should not try to help depressed patients with drugs and/or with psychotherapeutic/behavioral treatments given evidence of efficacy even though our treatment knowledge has limitations. The immense suffering of patients with major depression leads to ethical, moral, professional and legal obligations to treat patients with the best available tools at our disposal, while diligently and actively monitoring for adverse effects and actively revising treatment components as necessary.  相似文献   
256.
In the present study, we examined a bidimensional model of acculturation (which includes both heritage and U.S. practices, values, and identifications) in relation to hazardous alcohol use, illicit drug use, unsafe sexual behavior, and impaired driving. A sample of 3,251 first- and second-generation immigrant students from 30 U.S. colleges and universities completed measures of behavioral acculturation; cultural values (individualism, collectivism, and self-construal); ethnic and U.S. identity; and patterns of alcohol and drug use, engagement in potentially unsafe sexual activities, and driving while (or riding with a driver who was) intoxicated. Results indicate that heritage practices and collectivist values were generally protective against health risk behaviors, with collectivist values most strongly and consistently protective. Nonetheless, heritage identifications were positively associated with sexual risk taking for Hispanics. U.S. practices, values, and identifications were not consistently related to risk behavior participation. Results are discussed in terms of bidimensional approaches to acculturation, the immigrant paradox, and implications for counseling practice.  相似文献   
257.
Two individuals acting together to achieve a shared goal often have an emergent set of afforded behavioral possibilities that may not easily reduce to either acting alone. In a series of experiments we examined the critical boundaries for transitions in behavior for individuals walking through an aperture alone or alongside another actor as a dyad. Results from experiment 1 indicated that an intrinsically scaled critical boundary for behavioral transitions was different in individuals than in dyads performing a similar task. Experiment 2 demonstrated that observers are perceptually sensitive to the difference in action parameters for the dyad, while still maintaining perceptual sensitivity about the boundaries of action relative to individuals. In experiment 3, we determined that observers' perception of critical action boundaries for individuals and dyads has a similar informational basis (eye-height scaling). In experiment 4, we demonstrated that observers were able to perceive critical action boundaries for other dyads independently of membership. Together, these results suggest that individuals are sensitive to the affordances related to a joint action, and that this process may not entirely reduce to the perception of the affordances for each individual.  相似文献   
258.
Shannon N. Davis 《Sex roles》2010,63(11-12):786-790
This article comments on Lachance-Grzela and Bouchard (2010), which reviews research published 2000–2009 on the division of household labor. I argue that while Lachance-Grzela and Bouchard summarize the general state of knowledge on this topic, their review highlights what is missing from research on the division of household labor. To move beyond questioning why women perform the majority of housework requires a different set of questions, using a variety of data collection and analysis techniques, and a clear eye toward broader social theory.  相似文献   
259.
260.
Rapamycin, an inhibitor of the mammalian target of rapamycin (mTOR) kinase, has attracted interest as a possible prophylactic for post-traumatic stress disorder (PTSD)-associated fear memories. We report here that although rapamycin (40 mg/kg, i.p.) disrupted the consolidation and reconsolidation of fear-potentiated startle paradigm to a shock-paired context, it did not disrupt startle increases to a 4-sec odor cue, even though post-training increases in amygdala mTOR activity were prevented by rapamycin (also 40 mg/kg, i.p.). Thus, while rapamycin may prove useful in retarding the development of some PTSD-associated memories, its relative ineffectiveness against cued fear memories may limit its clinical usefulness.  相似文献   
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