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131.
首先分析了公路工程项目的质量特点和影响公路工程质量的因素,并就公路工程施工质量管理与控制问题做一简要论述.  相似文献   
132.
北太平洋巨型章鱼是170余种巨型章鱼中的一种。人们曾经误把它们看成为海怪,实际上,它们性格平和,并不像古老传说描述的那样会攻击船只。  相似文献   
133.
In an effort to understand the role of interhemispheric transfer in numerical development, we investigated the relationship between children's developing knowledge of numbers and the integrity of their white matter connections between the cerebral hemispheres (the corpus callosum). We used diffusion tensor imaging (DTI) tractography analyses to test the link between the development of the corpus callosum and performance on symbolic and non-symbolic numerical judgment tasks. We were especially interested in the interhemispheric connections of parietal cortex in 6-year-old children, because regions of parietal cortex have been implicated in the development of numerical skills by several prior studies. Our results revealed significant structural differences between children and adults in the fibers of the corpus callosum connecting the left and right parietal lobes. Importantly, these structural differences were predictive of individual differences among children in performance on numerical judgment tasks: children with poor numerical performance relative to their peers exhibited reduced white matter coherence in the fibers passing through the isthmus of the corpus callosum, which connects the parietal hemispheres.  相似文献   
134.
RESEARCH FINDINGS: The purpose of this study was to examine the relations of children's effortful control and quality of relationships with teachers to school attitudes longitudinally in an ethnically diverse and economically disadvantaged sample. Data were collected as part of a larger intervention project during mid-fall, winter, and late spring (ns = 823, 722, and 758, respectively) for 2 cohorts of 3- to 5-year-olds (collected during 2 different school years). Children's effortful control was assessed in the fall with parents' and teachers' reports and 2 behavioral measures. Teacher-child relationship quality was assessed mid-year with teachers' reports of closeness and conflict. Attitudes toward school were assessed in late spring using teachers' and students' reports of school avoidance and liking. Effortful control, in general, was positively correlated with teacher-child closeness and school liking and negatively correlated with conflict and school avoidance. Using structural equation modeling and controlling for sex and ethnicity, we found that effortful control was positively related to teacher-child relationship quality, which in turn was positively related to school attitudes. Furthermore, the relation of effortful control to school attitudes was mediated by teacher-child relationship quality. PRACTICE OR POLICY: Results provide evidence for the importance of relational processes that take place within the classroom context and have implications for teachers and clinicians working to increase school success in ethnic minority and low-income children.  相似文献   
135.
In this birth story, a young mother relates her experience of moving beyond fear of labor and birth and developing confidence in her ability to give birth without an epidural. Knowledge and support, including the support of a doula, during the last months of pregnancy helped this mother change her plans for the labor and birth. This story highlights the importance of continuous emotional and physical support and how knowledge and confidence set the stage for a satisfying, safe, and healthy birth.  相似文献   
136.
Substantial evidence documents the superiority of breastfeeding for mothers and breastmilk for babies. Although the American Academy of Pediatrics and the U.S. Healthy People 2010 initiative promote breastfeeding, current breastfeeding rates often fall short of recommendations. This study determined factors associated with exclusive breastfeeding 2 to 4 weeks following discharge from a large, urban, academic medical center striving for Baby-Friendly designation. Results indicated that mothers who breastfed within the first hour of birth (61%) were significantly more likely to be exclusively breastfeeding 2 to 4 weeks after discharge. Incorporating care practices that include a number of the "Ten Steps to Successful Breastfeeding," as recommended by the Baby-Friendly Hospital Initiative, may increase the duration of exclusive breastfeeding after discharge.  相似文献   
137.
This article examines the effect that postsecondary education has on earnings and the duration of time spent in the Social Security disability programs for young persons who are deaf or hard of hearing. Our hypothesis is that investments in postsecondary training increase the likelihood of employment for persons who are deaf or hard of hearing and thus reduce dependency on disability-related income support programs. A longitudinal data set based upon records from the National Technical Institute for the Deaf and Social Security administrative records is used for this analysis. We find that those who graduate, even those who graduate with vocational degrees, experience significant earnings benefits and reductions in the duration of time spent on federal disability programs when compared with those who do not graduate with a degree. This finding suggests that reductions in the duration of time spent on Social Security programs are not limited to those with the highest level of scholastic aptitude and that investments in post-secondary education can benefit a broad group of deaf and hard-of-hearing persons. In addition, the data show that individuals who attend college, but withdraw before graduation, fair no better economically than individuals who never attended college.  相似文献   
138.
In this article, we discuss the intuitive knowledge mothers have of their unborn baby. We propose a shift in focus from caregivers' merely providing information to first listening to pregnant mothers as they share their intuitive knowledge of their baby. This approach enables mothers and fathers or partners to know they are already parents to their unborn baby and empowers them to get in touch with their baby's presence and who he or she is during pregnancy. This intuitive knowledge may be a protective behavior that will enable mothers to keep babies safe during pregnancy.  相似文献   
139.
In line with other research, Udell, Dorey, and Wynne’s (in press) finding that dogs and wolves pass on some trials of a putative theory-of-mind test and fail on others is as informative about the methods and concepts of the research as about the subjects. This commentary expands on these points. The intertrial differences in the target article demonstrate how critical the choice of cues is in experimental design; the intersubject-group differences demonstrate how life histories can interact with experimental design. Even the best-designed theory-of-mind tests have intractable logical problems. Finally, these and previous research results call for the introduction of an intermediate stage of ability, a rudimentary theory of mind, to describe subjects’ performance.  相似文献   
140.
Preschool children (3–4 years old) were trained to perform two actions to gain different outcomes, in the form of video clips from different cartoons, before one of these outcomes was devalued by noncontingent exposure. The effect of outcome devaluation was subsequently assessed in an extinction test by giving children the opportunity to perform both actions in the absence of any outcomes. When the two actions were trained concurrently, performance during the test was modulated by outcome value and children showed a preference for the action trained with the currently valued outcome. By contrast, when each action was trained separately on different trials, test performance was insensitive to outcome devaluation. These effects of the training schedules are interpreted in terms of dual-process theories of action control.  相似文献   
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