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11.
Individuals with autism spectrum disorder (ASD) show differences in face processing abilities from early in development. To examine whether these differences reflect an atypical versus delayed developmental trajectory, neural responses to familiar and unfamiliar faces in twenty-four 18- to 47-month-old children with ASD were compared with responses of thirty-two 12- to 30-month-old typically developing children. Results of 2 experiments revealed that neural responses to faces in children with ASD resembled those observed in younger typically developing children, suggesting delayed development. Electrophysiological responses to faces were also related to parent report of adaptive social behaviors for both children with ASD and typical development. Slower development of the face processing system in ASD may be related to reduced self-directed "expected" experience with faces in early development.  相似文献   
12.
    
College-level biology courses contain many complex processes that are often taught and learned as detailed narratives. These processes can be better understood by perceiving them as dynamic systems that are governed by common fundamental principles. Conservation of matter is such a principle, and thus tracing matter is an essential step in learning to reason about biological processes. We present here multiple-choice questions that measure students' ability and inclination to trace matter through photosynthesis and cellular respiration. Data associated with each question come from students in a large undergraduate biology course that was undergoing a shift in instructional strategy toward making fundamental principles (such as tracing matter) a central theme. We also present findings from interviews with students in the course. Our data indicate that 1) many students are not using tracing matter as a tool to reason about biological processes, 2) students have particular difficulties tracing matter between systems and have a persistent tendency to interconvert matter and energy, and 3) instructional changes seem to be effective in promoting application of the tracing matter principle. Using these items as diagnostic tools allows instructors to be proactive in addressing students' misconceptions and ineffective reasoning.  相似文献   
13.
OBJECTIVES: Since the late 1980s, there has been a strong theoretical focus on psychological and social influences of perpetration of child sexual abuse. This paper presents the results of a review and meta-analysis of studies examining risk factors for perpetration of child sexual abuse published since 1990. METHOD: Eighty-nine studies published between 1990 and April of 2003 were reviewed. Risk factors were classified into one of the following six broad categories: family factors, externalizing behaviors, internalizing behaviors, social deficits, sexual problems, and attitudes/beliefs. Sex offenders against children (SOC) were compared to three comparison groups identified within the 89 studies: sex offenders who perpetrated against adults (SOA), non-sex offenders, and non-offenders with no history of criminal or sexual behavior problems. RESULTS: Results for the six major categories showed that SOC were not different from SOA (all d between -.02 and .14) other than showing lower externalizing behaviors (d=-.25). Sex offenders against children were somewhat different from non-sex offenders, especially with regard to sexual problems and attitudes (d=.83 and .51). Sex offenders against children showed substantial differences from non-offenders with medium sized effects in all six major categories (d's range from .39 to .58). CONCLUSION: Child sex offenders are different from non-sex offenders and non-offenders but not from sex offenders against adults. PRACTICE IMPLICATIONS: This study suggests that the presence of general risk factors may lead to a variety of negative behavioral outcomes, including the perpetration of child sexual offending. Family factors were strongly related to the perpetration of child sex offending (vs. non-sexual offending or non-offending) and may be valuable intervention points for interrupting the development of child sex offending, as well as other negative behaviors. Other potential points for intervention may focus on the development of appropriate social and emotional skills that contribute to sexual offending.  相似文献   
14.
Do siblings develop similar attachment relationships with their mother? Attachment theory suggests that brothers and sisters growing up in the same family are likely to relate in similar ways to their parents, at least when parental attachment representations and interactive styles remain stable across time. In the current study, sibling attachment data from three research groups (from Pennsylvania State University, Leiden University, and the University of Western Ontario) have been pooled to assemble a sufficiently large sample of observations (N = 138 sibling pairs) for a detailed comparison of sibling attachment relationships. Spacing between the births, differences in maternal sensitivity, and gender of siblings were examined as possible sources of concordance of nonconcordance. Attachment security (including disorganized attachment) of each sibling was assessed with the Strange Situation procedure between 12 and 14 months after birth. Maternal sensitivity was observed with the same rating scale in a laboratory play session in one of the studies and in home observations in the others. Sibling relationships were found to be significantly concordant when classified as secure/nonsecure (62% concordance, p < .01, 1-tailed, intraclass correlation = .23) but not when further subcategorized. Maternal insensitivity to both siblings (shared environment) was associated with concordance of sibling nonsecurity. Siblings of the same gender were more likely to form concordant relationships with their mother (68%; p < .01, 1-tailed, intraclass correlation = .37) than those of opposite gender. Same-sex sibling concordance was comparable to the concordance found for monozygotic twins in earlier studies. Genetic factors may, therefore, play a relatively small role in the development of attachment.  相似文献   
15.
We present a diagnostic question cluster (DQC) that assesses undergraduates' thinking about photosynthesis. This assessment tool is not designed to identify individual misconceptions. Rather, it is focused on students' abilities to apply basic concepts about photosynthesis by reasoning with a coordinated set of practices based on a few scientific principles: conservation of matter, conservation of energy, and the hierarchical nature of biological systems. Data on students' responses to the cluster items and uses of some of the questions in multiple-choice, multiple-true/false, and essay formats are compared. A cross-over study indicates that the multiple-true/false format shows promise as a machine-gradable format that identifies students who have a mixture of accurate and inaccurate ideas. In addition, interviews with students about their choices on three multiple-choice questions reveal the fragility of students' understanding. Collectively, the data show that many undergraduates lack both a basic understanding of the role of photosynthesis in plant metabolism and the ability to reason with scientific principles when learning new content. Implications for instruction are discussed.  相似文献   
16.
This paper describes a newly adapted instrument for measuring novice-to-expert-like perceptions about biology: the Colorado Learning Attitudes about Science Survey for Biology (CLASS-Bio). Consisting of 31 Likert-scale statements, CLASS-Bio probes a range of perceptions that vary between experts and novices, including enjoyment of the discipline, propensity to make connections to the real world, recognition of conceptual connections underlying knowledge, and problem-solving strategies. CLASS-Bio has been tested for response validity with both undergraduate students and experts (biology PhDs), allowing student responses to be directly compared with a consensus expert response. Use of CLASS-Bio to date suggests that introductory biology courses have the same challenges as introductory physics and chemistry courses: namely, students shift toward more novice-like perceptions following instruction. However, students in upper-division biology courses do not show the same novice-like shifts. CLASS-Bio can also be paired with other assessments to: 1) examine how student perceptions impact learning and conceptual understanding of biology, and 2) assess and evaluate how pedagogical techniques help students develop both expertise in problem solving and an expert-like appreciation of the nature of biology.  相似文献   
17.
在质心坐标系中可以采用等效的不同方法来表达多粒子体系的角动量。 Ⅰ 实验室坐标系 我们以m_i,ri和vi表示一个由n个粒子组成的体系的质量、矢径和速度。这个多粒子系统的质心位置是  相似文献   
18.
一、地质科学和环境 地质科学家进入环境领域相对较晚,在这一领域,工程师、地理学家、生物学家、气象学家、海洋学家和一些其它学科的科学家领先于他们。这已经对地质科学家在某些主要的应用科学团体和研究项目的地位和需  相似文献   
19.
    
Vines G 《New scientist (1971)》1995,147(1994):37-39
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20.
    
Since fall 2009, reference librarians at The George Washington University's Himmelfarb Health Sciences Library have been embedded in online classes through Blackboard within the School of Nursing and School of Medicine and Health Sciences. The authors sought to determine the types of questions asked of the librarian, with the goal of informing future interactions with distance education classes to help develop a standard \"protocol\" for working with this population of students. Eighty-two questions were categorized and qualitatively analyzed. The findings have prompted librarians to explore tools such as Elluminate Live!, a tool that allows librarians to provide synchronous instruction within the Blackboard environment.  相似文献   
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