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291.
292.
“Macroappraisal, the next frontier” describes a records disposition pilot project which was based on a refinement of the current
macroappraisal methodology in use at Library and Archives Canada. Still very much a work in progress, the refined approach
builds upon macroappraisal theory and methodology, and this paper presents its application to Fisheries and Oceans Canada,
a major federal government department in the Government of Canada. The project focused on providing the institution with total
records disposition coverage based on a single archival appraisal and two Records Disposition Authorities. This paper demonstrates
the feasibility of appraising records at the mandate level instead of at the function or program level. It also outlines and
points to the benefits and advantages of appraising large government institutions intheir totality rather than in smaller,
discrete sectors, branches, or divisions.
We wish to thank the journal’s readers for their comments on an earlier draft of this article. We also wish to thank Candace
Loewen for her insights, comments, and encouragement. Thanks are also extended to our colleagues who commented on various
aspects of the project during Library and Archives Canada (LAC) appraisal seminars. Kerry Badgley also wishes to thank Sarah,
Paul, and Shannon Badgley for providing a daily reminder of why it is important to document the past. 相似文献
293.
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295.
Automatic tracing and segmentation of rat mammary fat pads in MRI image sequences based on cartoon-texture model 总被引:1,自引:1,他引:0
The growth patterns of mammary fat pads and glandular tissues inside the fat pads may be related with the risk factors of breast cancer.Quantitative measurements of this relationship are available after segmentation of mammary pads and glandular tissues.Rat fat pads may lose continuity along image sequences or adjoin similar intensity areas like epidermis and subcutaneous regions.A new approach for automatic tracing and segmentation of fat pads in magnetic resonance imaging (MRI) image sequences is presented,which does not require that the number of pads be constant or the spatial location of pads be adjacent among image slices.First,each image is decomposed into cartoon image and texture image based on cartoon-texture model.They will be used as smooth image and feature image for segmentation and for targeting pad seeds,respectively.Then,two-phase direct energy segmentation based on Chan-Vese active contour model is applied to partitioning the cartoon image into a set of regions,from which the pad boundary is traced iteratively from the pad seed.A tracing algorithm based on scanning order is proposed to accurately trace the pad boundary,which effectively removes the epidermis attached to the pad without any post processing as well as solves the problem of over-segmentation of some small holes inside the pad.The experimental results demonstrate the utility of this approach in accurate delineation of various numbers of mammary pads from several sets of MRI images. 相似文献
296.
Social and Environmental Factors Associated With Preschoolers' Nonsedentary Physical Activity 总被引:2,自引:0,他引:2
William H. Brown Karin A. Pfeiffer Kerry L. McIver Marsha Dowda Cheryl L. Addy and Russell R. Pate 《Child development》2009,80(1):45-58
The twofold purposes of the investigation were (a) to describe with direct observation data the physical activity behaviors and the accompanying social and environmental events of those behaviors for children in preschools and (b) to determine which contextual conditions were predictors of moderate to vigorous physical activity (MVPA) and nonsedentary physical activity (i.e., light activity + MVPA) for 3-, 4-, and 5-year-old children during their outdoor play. The results indicate that preschoolers' physical activity is characterized as sedentary in nature throughout their preschool day (i.e., 89% sedentary, 8% light activity, and 3% MVPA). During outdoor play periods, when children are most likely to be physically active, some contextual and social circumstances better predict their physical activity. Implications for policy makers, practitioners, and researchers are discussed. 相似文献
297.
Franklin R. Manis Mark S. Seidenberg Lynne Stallings Marc Joanisse Caroline Bailey Laurie Freedman Suzanne Curtin Patricia Keating 《Annals of dyslexia》1999,49(1):105-134
There is a consensus that dyslexia is on a continuum with normal reading skill and that dyslexics fall at the low end of the
normal range in phonological skills. However, there is still substantial variability in phonological skill among dyslexic
children. Recent studies have focused on the high end of the continuum of phonological skills in dyslexics, identifying a
“surface” dyslexic, or “delayed” profile in which phonological skills are not out of line with other aspects of word recognition.
The present study extended this work to a longitudinal context, and explored differences among subgroups of dyslexics on a
battery of component reading skills. Third grade dyslexics (n=72) were classified into two subgroups, phonological dyslexics and delayed dyslexics, based on comparisons to younger normal
readers at the same reading level (RL group). The children were tested at two points (in third and fourth grade). The results
revealed that the classification of dyslexics produced reliable, stable, and valid groups. About 82 percent of the children
remained in the same subgroup category when retested a year later. Phonological dyslexics were lower in phoneme awareness
and expressive language. Delayed dyslexics tended to be slower at processing printed letters and words but not at rapid automatic
naming of letters, and relied more heavily on phonological recoding in reading for meaning than did phonological dyslexics.
A subset of the delayed dyslexics with the traditional “surface dyslexic” pattern (relatively high pseudoword and low exception
word reading) was also identified. The surface subgroup resembled the RL group on most measures and was not very stable over
one year. The results are discussed in light of current models of dyslexia and recent subgrouping schemes, including the Double-Deficit
Hypothesis. 相似文献
298.
The metabolic cost of locomotion at any given speed, when expressed per kilogram of body mass, is greater for children than for older individuals. Incomplete explanations for the age-related difference motivated this study, which used a multidisciplinary method to examine metabolic, kinematic and electromyographic data from three maturational groups of children. Thirty children aged 7-8 (n = 10), 10-12 (n = 10) and 15-16 (n = 10) years completed 4 min bouts of submaximal treadmill exercise at six speeds--two walking and four running--assigned in random order. Metabolic (net VO2), kinematic (total body mechanical power, energy transfer rates, stride rate) and electromyographic (co-contraction of agonist and antagonist muscles in thigh and leg segments) data were collected. Multiple regression analysis was performed with net VO2 or efficiency as the dependent variable and mechanical power, thigh and leg co-contraction, stride rate and age as independent variables. It was possible to explain up to 77% of the age-related variance in net VO2 and 62% of the variation in efficiency using combinations of these variables. Age was the best single predictor of both VO2 and efficiency. Co-contraction, possibly used to enhance joint stability, was an important component of the observed age-related differences, although mechanical power was not. Additional variance might be explained as specific growth-related factors affecting the metabolic cost of locomotion are identified, as mechanical work models improve, and as methods are developed to measure the effects of stored elastic energy and the metabolic cost of isometric muscle actions. 相似文献
299.
The European Distance Education Network (EDEN) is a fairly new European network for open and distance learning, established after the fall of the Berlin Wall. In this paper, the President and Executive Secretary of EDEN summarizes its establishment, main achievements and areas of activities. 相似文献
300.