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41.
Child Development and the Social Demography of Childhood 总被引:1,自引:0,他引:1
Donald J. Hernandez 《Child development》1997,68(1):149-169
This article provides background information and a practical guide for including demographic information in developmental research. First, it portrays historic demographic trends reflecting critical ways in which the family and economic environments of children have been, and continue to be, transformed in the United States. Second, it presents current demographic statistics to provide a basis for researchers to compare their special study population to the general population of children and to formulate specific hypotheses about ways in which their result might differ for children in various demographic situations. Third, it offers an Appendix with standardized wording for a minimum set of questions needed to measure the demographic characteristics and environments of children. The Appendix provides researchers the technical capacity to collect such data, so they can develop and test hypotheses about how family and econmic environments shape child development processes and outcomes. 相似文献
42.
This paper addresses a neglected topic in the knowledge management literature: how the size of a network of actors affects the nature of intra-network social relations and knowledge processes. It makes a theoretical contribution to developing understanding in this area drawing on a range of literatures including practice-based perspectives on knowledge, the literature on the embeddedness of social relations, and relevant knowledge management literature. The central focus of this paper is on the relationship between network size, network density, and how these variables affect intra-network knowledge processes. It suggests that as network size increases network density is likely to decrease (as it becomes problematic for the actors in such networks to retain strong ties with a significant proportion of the network's members), which it will be suggested has significant ramifications for intra-network knowledge processes. This paper concludes by reflecting on the implications of the ideas developed for network-based forms of organizing, and innovation processes. 相似文献
43.
44.
The need for those working in a variety of settings to interact effectively with technical experts has grown dramatically in recent years as computers have become essential to the performance of an increasing broad range of professional work. This article presents a case of this sort of interprofessional interaction, exploring the process and outcomes of collaboration between technical professionals and educators working to bring Internet access to an urban public school district. Drawing on field note and interview data, the case reported here illustrates how differences in institutional routines and professional values can generate differing agendas, contrasting assumptions, and contrasting expectations concerning project products and outcomes among collaborators from different professional worlds. In the case we describe, these differences affected such central matters as the types and usefulness of technical resources to which users had access as well as users' confidence in the technology. The case also illustrates how aspects of this interprofessional conflict were addressed through an organizational change. The kinds of issues that arose in this project are likely to occur in a variety of professional settings; therefore, examination of this case provides insight into a variety of issues and dynamics that should be considered when embarking upon or analyzing any interprofessional collaborative effort, and particularly one that involves technical professionals. 相似文献
45.
Donald L. Margolis 《Journal of The Franklin Institute》1983,316(3):261-271
Semi-active systems are those in which a passive, dissipative element (damper, friction clutch, fluid orifice) is modulated, via low power inputs, to enhance the performance of its associated dynamic system. This type of control is inherently nonlinear, thus forcing the closed-loop response of the total system to be determined numerically using a digital computer. Although, strictly speaking, the frequency response for nonlinear systems does not exist, it is typical to simulate semi-active systems with sinusoidal input and present results as frequency transmissibilities. This paper uses energy dissipation per cycle to determine an approximate frequency response of semi-active systems requiring only a calculator for numerical analysis. 相似文献
46.
Vertesi J 《Endeavour》2004,28(2):64-68
In their race to provide the ultimate guide to the moon, two 17th-century astronomers proposed lunar maps and nomenclatures that they hoped would gain international currency. But the names we use today were those proposed by the Jesuit, a friend of Galileo's persecutors, in a book whose purpose was to refute the Copernican system once and for all. We now believe that Riccioli was wrong about the universe, but why do we still use his nomenclature? The keys to this foundational visual debate in astronomical image-making are the moon maps themselves. 相似文献
47.
Jackson R Baird W Davis-Reynolds L Smith C Blackburn S Allsebrook J 《Health information and libraries journal》2007,24(2):95-102
OBJECTIVES: The objectives of this work were to identify the sources of information currently received, information-seeking behaviours, information requirements and preferences for future information provision amongst health and social care professionals providing care to children with health care needs. METHODS: Data were collected using a cross-sectional postal questionnaire survey. RESULTS: A wide range of information resources was reported as being available to professionals. However, a large proportion of respondents found it necessary to perform additional searches for information, suggesting that current resources were not satisfying their needs. The majority of professionals reported a preference for electronic formats, whilst a smaller proportion preferred hard copy materials. Participants promoted the use of informal networks as a means of support and exchange of information. CONCLUSION: Supplementing the information that is provided in electronic and hard copy formats, by enhancing informal networks, may be the most effective way of meeting the information needs of this group of professionals. 相似文献
48.
Stability in cardiac indicators before birth and their utility in predicting variation in postnatal development were examined. Fetal heart rate and variability were measured longitudinally from 20 through 38 weeks gestation (n = 137) and again at age 2 (n = 79). Significant within-individual stability during the prenatal period and into childhood was demonstrated. Fetal heart rate variability at or after 28 weeks gestation and steeper developmental trajectories were significantly associated with mental and psychomotor development at 2 years (n = 82) and language ability at 2.5 years (n = 61). These data suggest that the foundations of individual differences in autonomic control originate during gestation and the developmental momentum of the fetal period continues after birth. 相似文献
49.
The understanding and use of historical concepts specified in national history standards pose many challenges to students. These challenges include both the acquisition of content knowledge and the use of that knowledge in ways that require higher order thinking. All students, including adolescents with learning disabilities (LD), are expected to understand and use concepts of history to pass high-stakes assessments and to participate meaningfully in a democratic society. This article describes Content Enhancement Routines (CERs) to illustrate instructional planning, teaching, and assessing for higher order thinking with examples from an American history unit. Research on the individual components of Content Enhancement Routines will be illustrated with data from 1 of the routines. The potential use of integrated sets of materials and procedures across grade levels and content areas will be discussed. 相似文献
50.
Prevalence of child sexual abuse reported by a cross-sectional sample of New Zealand women 总被引:1,自引:0,他引:1
OBJECTIVE: The objective is to describe the prevalence of child sexual abuse (CSA) among women in New Zealand, document ethnic specific rates, and outline the frequency of abuse experienced and the most commonly identified perpetrators. Associations between CSA and later adverse consequences were also explored. METHODS: Retrospective report from a random sample of 2,855 women aged 18-64 years old in two regions in New Zealand. Face-to-face interviews with one randomly selected woman from each household were conducted. RESULTS: The overall prevalence rates for CSA were 23.5% for women from the urban region and 28.2% from the rural region. In both urban and rural regions, Māori women more frequently reported experiences of CSA than women from European and other ethnic groups (urban: 30.5% vs. 17.0% and rural: 35.1% vs. 20.7%). The median age of onset of the abuse was 9 years, and the median estimated age of the abuser was 30 years. Half of those who experienced CSA reported that it occurred once or twice, 27% "a few times," and 23% "multiple times." Sole perpetrators were involved in 83% of cases. The majority of cases were perpetrated by a family member, most frequently male. Compared with non-victims, victims of CSA were twice as likely to experience later intimate partner violence and violence by others. CONCLUSIONS: This study reports on a large, population-based sample in an ethnically diverse population in New Zealand, providing the first ethnic-specific rates of CSA available. Findings suggest important priorities for prevention and intervention activities. 相似文献