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91.
92.
The reduction of semantic priming following letter search of the prime suggests that semantic activation can be blocked if attention is allocated to the letter level during word processing. Is this true even for the very fast-acting component of semantic activation? To test this, the authors explored semantic priming of lexical decision at stimulus onset asynchronies (SOAs) of either 200 or 1000 ms. Following semantic prime processing, priming occurred at both SOAs. In contrast, no priming occurred at the long SOA following letter-level processing. Of greatest interest, at the short SOA there was priming following the less demanding consonant/vowel task but not following the more attention-demanding letter search task. Hence, semantic activation can occur even when attention is directed to the letter level, provided there are sufficient resources to support this activation. The authors conclude that the default setting during word recognition is for fast-acting activation of the semantic system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
The United States has historically excelled in the design of products, processes and new technologies. Capitalizing on this historical strength to teach applied mathematics and science has many positive implications on education. First, engineering design can be used as a vehicle for addressing deficiencies in mathematics and science education. Second, as achievement in mathematics and science is enhanced, a greater number of students at an earlier age will be exposed to technical career opportunities. Third, enhancing elementary and secondary curricula with engineering design can attract underrepresented populations, such as minorities and females, to engineering as a profession. This paper describes a new and innovative engineering design curriculum, under development in the Austin Independent School District (AISD) in Austin, TX. The philosophic goals upon which the curriculum is based include: integrating the design problem-solving process into elementary schools, demonstrating the relationship of technical concepts to daily life, availing teachers with instructional strategies for teaching applied (as opposed to purely theoretical) science and mathematics, and teaching teamwork skills that are so greatly needed in industry and everyday life. Based on these goals, kindergarten, first grade, and second grade engineering design lessons have been piloted in AISD, in conjunction with a University of Texas program for teacher enhancement and preparation.  相似文献   
94.
As federal dollars available for highway projects are tightened and as demand for more highway capacity continues to increase, transportation officials seek more innovative financing methods. One of the more common methods has been to toll new highway projects. Recently, tollways also have been considered for existing, free-access roadways, i.e., nontolled, infrastructure segments. Transportation planners must consider that this so-called “innovative” financing technique, i.e., the decision to toll existing and new roadways, is subject to provisions of the National Environmental Protection Act (NEPA). This renewed interest in tolling mandates that transportation planners revisit the requirements of NEPA, and in this context, its applicability to decisions to toll roads for financing of highway projects. NEPA requires that, prior to construction of a bridge or highway, the head of the federal agency that is committing funds to the project must evaluate the effect of the project on the human environment; the effect of the project on the habitat of an endangered species, which implicates provisions of the Endangered Species Act; the effect of the project on any historic properties in the vicinity of the project, which implicates provisions of the National Historic Preservation Act, and the effect of the project on minority or low-income-populations, called environmental justice, which implicates Title VI of the Civil Rights Act of 1964. In this paper, we analyze the requirements of NEPA as they relate to Title VI of the Civil Rights Act of 1964. The interrelation of the two acts now mandates that the transportation planner consider an environmental justice concept in planning for highway and bridge projects. The intent of this paper is to provide some guidance to transportation planners in light of the environmental justice issues implicated by Title VI of the Civil Rights Act of 1964 as they begin the planning stages for highway and bridge projects.  相似文献   
95.
Electrolytic microlesions aimed at the dorsomedial portion of the ventromedial nucleus (VMN) of the hypothalamus were generated, and effects on copulation, 50-kHz vocalizations, scent marking, and sexual motivation were measured. Male rats were tested before and after lesions, after castration, and after testosterone replacement. Three control groups were used: One received sham surgery, another received no surgery or testosterone replacement, and a 3rd received lesions primarily outside the VMN. VMN lesions produced impairments in testosterone's ability to restore ultrasonic vocalizations and scent marking, assessed with 2 different test methods. Copulation, sexual motivation, and weight gain were largely unaffected, although some differences were observed in copulatory efficiency. The authors conclude that the integrity of the VMN is important for full expression of sociosexual behaviors in male rats. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
96.
25 girls and 31 boys (aged 4–9 yrs) were presented with novel objects in 3 sex-labeled boxes and were given 6 min to explore the objects. Memory for information about the objects was tested 1 wk later. Results show that Ss tactually explored novel objects labeled for their own sex more than similar objects labeled for the other sex and remembered more detailed information about own-sex than other-sex objects. Furthermore, regardless of labeling condition, Ss recalled the sex-typed label applied by the experimenter to each object. As expected from the C. L. Martin and C. F. Halverson, Jr. (see record 1982-05576-001) schematic processing model, an incentive to remember did not improve recall in any labeling condition. The sex-typed labeling effects on exploration occurred primarily among the older children, whereas the effects on recall appeared among the younger and older boys and the younger girls. The results suggest that sex stereotypes restrict children's behavior by limiting their competence rather than their performance. Findings are discussed in relation to an earlier study by the 1st author and R. C. Endsley (see record 1983-32397-001). (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
Dielectric properties of the inflated and deflated fceline lung in vivo were investigated at frequencies from 10 kHz to 100 MHz. A computer-controlled network analyzer and a multiring capacitive sensor were employed. It was found that in the frequency range investigated, both the dielectric constant and the conductivity of the deflated lung were higher than those of the inflated one. The analysis of the experimental data was performed using two approaches: the loss-tangent method and the curve-fitting computer program called STEPIT. It was found that in the middle band of frequencies for both inflated and deflated states of the lung, the dielectric response mainly reflects the membrane polarization of the capillary erythrocytes with possible contributions of other components, e.g., the pulmonary microphages. The dielectric relaxation time for the capillary erythrocytes in the lung is similar to that for the packed cells, which is much longer than for the erythrocytes at physiological concentrations. The dielectric parameters at low frequencies obtained using the STEPIT program differ significantly between the inflated and deflated lung. The observed dielectric data reflect at least two overlapping dispersions: of lung capillary erythrocytes and of cellular structures forming the alveoli.  相似文献   
98.
Two experiments examined priming in the lexical decision task, an indirect test of memory. Experiment 1 manipulated type of processing during study of unrelated word pairs. Recognition of individual words benefited more from semantic than from nonsemantic processing. Repetition priming in lexical decision depended on the context in which the target appeared. Targets preceded at test by unstudied primes showed greater repetition priming if processed nonsemantically during study; targets preceded at test by studied primes were not affected by type of processing at study. Interestingly, studied targets were facilitated more by studied than by unstudied primes regardless of whether the prime came from the same pair as the target. This list-wide episodic priming occurred under all four processing conditions in Experiment 1 (consonant counting, rote rehearsal, pleasantness rating, and sentence generation) with a 250-ms stimulus onset asynchrony. Experiment 2 showed that this list-wide episodic priming disappeared by 1,000 ms, suggesting that it had resulted from relatively transient activation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
We investigated (a) the relation of maternal depression to perceptions of externalizing and internalizing disorders in children and (b) quality of communication in a mother–child interaction task as a function of maternal depression and perceptions of the child. 64 children of unipolar or bipolar mothers, chronic medically ill or normal mothers were studied; clinical diagnoses, children's reports, and teachers' ratings served as objective criteria of children's maladjustment. Maternal depression defined by current symptomatology on the Beck Depression Inventory and by psychiatric status was not associated with misperceptions of psychopathology. Maternal depression interacted with children's actual behaviors to predict mothers' perceptions: nondepressed mothers were less accurate reporters of problems in children than were depressed mothers. Depressed mothers who perceived maladjustment in their disturbed children made more negative comments in interactions than did nondepressed mothers of disturbed children. The apparent mutual impact of mothers' and children's maladjustment requires fuller exploration in offspring studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
Contends that C. A. Kiesler (see record 1983-24077-001) has drawn too many inferences based on incomplete and inaccurate analyses in his article on public and professional myths about mental hospitalization. Specifically, the present authors differ with Kiesler's contention that mental hospitalization is increasing, his implicit assumption that episodes of mental disorder in general hospitals without psychiatric units are equivalent to those in general hospitals with such units, and his comparison of effects of hospitalization for mental illness vs alternate modes of care. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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