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71.
Because access to new technologies is unequally distributed, there has been considerable debate about the growing gap between the so‐called information‐rich and information‐poor. Such concerns have led to high‐profile information technology policy initiatives in many countries. In Australia, in an attempt to ‘redress the balance between the information rich and poor’ by providing ‘equal access to the World Wide Web’ (Virtual Communities, 2002 Virtual Communities (2002) About us. Available online at: http://www.virtualcommunities. com.au (accessed 18 August 2002)  [Google Scholar]), the Australian Council of Trade Unions, Virtual Communities (a computer/software distributor) and Primus (an Internet provider) in late 1999 formed an alliance to offer relatively inexpensive computer and Internet access to union members in order to make ‘technology affordable for all Australians’ (Virtual Communities, 2002 Virtual Communities (2002) About us. Available online at: http://www.virtualcommunities. com.au (accessed 18 August 2002)  [Google Scholar]). In this paper, we examine four families, one of which had long‐term Information and Communication Technologies (ICT) access, and three of which took advantage of the Virtual Communities offer to get home computer and Internet access for the first time. We examine their engagement with ICT and suggest that previously disadvantaged family members are not particularly advantaged by their access to ICT.  相似文献   
72.
Fourteen behavioral measures were ranked according to their ability to differentiate performances of a wild population of mice from three domestic inbred strains. These “wildness” rankings were then analyzed for their ability to predict genetic and Genotype by Environment interactions. Genetic parameters were derived from analysis of three inbred domestic strains and their three hybrid crosses via the diallel technique of genetic analysis. Genotype by Environment interactions were assessed both as mean differences in stock performances resulting from rearing in a laboratory vs naturalistic environment and as differences in environmental variability within stock genotypes. Behavioral characters ranking high on “wildness” failed to demonstrate any unitary pattern of Genotype by Environment interactions. The diallel genetic analysis revealed many examples of additive variation but relatively few examples of dominant variation. An extremely wide range of interactions occurred between genotype and rearing environments, with “wildness” and “developmental homeostasis” concepts both failing to account for all the observed interactions.  相似文献   
73.
Expanding and diversifying the STEM (science, technology, engineering, and mathematics) workforce is a national priority. The National Science Foundation is investing efforts at post secondary education institutions to engage individuals who have been historically underrepresented in STEM. This paper investigated the use of strategies to broaden participation in STEM by grantees of NSF’s Advanced Technological Education (ATE), who are primarily located at 2-year colleges. The ATE program focuses on developing and improving technician training programs to prepare students for employment in fields that rely on advanced technologiessuch as nanotechnology, photonics, and mechatronics. A survey, conducted annually by the authors of this study, was used to collect data from ATE grantees on their use and perceptions of strategies to broaden participation in STEM. The findings showed that strategies related to motivation and access to enhance recruitment are more widely used then strategies that improve retention. Respondents identified strategies related to providing financial assistance, mentoring, and conducting outreach activities as the most effective for reaching and engaging underrepresented minority students in academic programs. Despite these perceptions, these strategies seem to be underutilized among this group.  相似文献   
74.
The goals of this research were to explore the current literature regarding associations between psychological stress and adverse fetal outcome, associations between aerobic exercise and psychological stress reduction, and associations between aerobic exercise and fetal outcome. The published studies that were located provide evidence of the following: 1) Stress reactivity increases physiologically during pregnancy, 2) pregnant women may experience additional stressors that are usually not experienced in a nonpregnant state, 3) psychological stress in pregnancy is associated with adverse fetal outcome, 4) exercise can be a method of stress reduction, 5) exercise in pregnancy is not associated with adverse fetal outcome, and 6) exercise in pregnancy may provide benefit to the fetus. Data were analyzed from an original study and associations were reported between psychological stress-management activities and participation in aquatic aerobic exercise classes. No reports were available investigating an exercise-induced reduction in psychological stress with fetal outcome.  相似文献   
75.
The primary purpose of this research was to examine the construct validity of the Child Abuse Potential Inventory by comparing maltreating and high-risk parents' CAP Inventory abuse scores to their behavior during interactions with their children. A second purpose was to determine the degree to which CAP Inventory scores and parenting behavior were related to several known correlates of abuse, as measured by parent and teacher reports. Participants (n = 41) included abusive and high-risk parents and their children referred to a treatment group. Correlational analyses revealed that CAP Inventory scores and observed parenting style yielded highly related findings, supporting construct validity of the CAP Inventory. However, the CAP Inventory and observed behavior index showed a different pattern of relationships to the risk correlates. Implications for assessment of risk status are discussed and recommendations are provided for continued research.  相似文献   
76.
This paper examines the meaning of context in relation to ontology based query expansion and contains a review of query expansion approaches. The various query expansion approaches include relevance feedback, corpus dependent knowledge models and corpus independent knowledge models. Case studies detailing query expansion using domain-specific and domain-independent ontologies are also included. The penultimate section attempts to synthesise the information obtained from the review and provide success factors in using an ontology for query expansion. Finally the area of further research in applying context from an ontology to query expansion within a newswire domain is described.  相似文献   
77.
In distributed information retrieval systems, document overlaps occur frequently among different component databases. This paper presents an experimental investigation and evaluation of a group of result merging methods including the shadow document method and the multi-evidence method in the environment of overlapping databases. We assume, with the exception of resultant document lists (either with rankings or scores), no extra information about retrieval servers and text databases is available, which is the usual case for many applications on the Internet and the Web. The experimental results show that the shadow document method and the multi-evidence method are the two best methods when overlap is high, while Round-robin is the best for low overlap. The experiments also show that [0,1] linear normalization is a better option than linear regression normalization for result merging in a heterogeneous environment.
Sally McCleanEmail:
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78.
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   
79.
This longitudinal study of 105 economically disadvantaged children examined the relation between reading problems and internalizing behavior in 3rd- and 5th-grade assessments (8- to 12-year olds). The variable-centered results showed that reading problems predicted change in internalizing behavior in the context of child and family predictors. The person-centered results showed that children with reading problems in both grades had higher internalizing scores in 5th grade but not in 3rd grade than children with reading problems in 3rd grade or no problems. Child-reported negative emotion experiences varied similarly across grade. The results tie reading problems to emotional distress in school and support conclusions about the direction of effects and the internalization of academic difficulty for disadvantaged children.  相似文献   
80.
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