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171.
Purpose: To investigate the effects of a 12-week home walking program on cardiovascular parameters, fatigue perception, and walking distance in persons with multiple sclerosis (MS). Methods: Twelve ambulatory persons with MS, not currently participating in exercise were randomly assigned to control (C) or experimental groups (EX). Pretest data collection included resting HR, BP, fatigue perception (Fatigue Severity Scale), and 6-minute walk test. EX received a home walking program (30 min, 3 × week, × 12 weeks), using a modification of Karvonen''s formula to calculate HR range. A HR monitor was used to adjust walking speed. The C group refrained from any regular exercise. Posttest data were collected at week 12 and analyzed using the Mann-Whitney U Test. Results: No statistically significant differences were noted between groups in any measured parameters; however, walking distance and Physiologic Cost Index did improve in the exercise group. Conclusion: No adverse events or increase in fatigue levels related to the exercise intervention were reported in this study. This home walking program may not be of sufficient intensity to elicit significant cardiovascular changes. Abnormal cardiac responses have been documented in this population, which may have affected the results. Clinicians may need to use alternate measures to assess fitness in this population.Key Words: multiple sclerosis, home walking program, cardiovascular, aerobic  相似文献   
172.
Rainsford Island is an 11-acre island located in central Boston Harbor, Massachusetts. The proximity to the City of Boston resulted in the Island being used as a quarantine facility, poorhouse, veteran's hospital and school for wayward boys from 1737 to 1920. The Island consists of two linked topographic highs of glacial origin connected by a spit formed from reworked glacial material. The majority of the southern “high” is only slightly elevated above present-day sea level and was the site of a cemetery that serviced the quarantine facility, poorhouse and veteran's hospital. Historical research indicates that more than 1100 persons were buried on Rainsford during this time. The records for the cemetery have been lost through fire and only four sandstone posts presently mark the cemetery. Our team sought to (1) assess shoreline change on the southern portion of the Island; (2) map the boundaries of the unmarked cemetery using ground-penetrating radar and (3) determine the vulnerability of the cemetery to coastal erosion caused by long-term sea-level rise and episodic flooding. Shoreline change analysis indicates that the southern portion of the island has eroded on the north-facing beach at a rate of 0.2 m/yr while the south-facing beach has been stable. Topographic analysis of the landscape indicates that the central area of the southern portion is less than 1 m above sea level with a slightly elevated rim approximately 2 m above sea level. The ground-penetrating radar surveys indicated that the low-lying central portion exhibited evidence for burials. The results indicate that the cemetery is vulnerable to erosion and coastal flooding. A storm with a coastal storm surge of approximately 1 m will result in flooding of the cemetery. The northern edge of the cemetery is extremely vulnerable to erosion and the first mapped burial on the northern side will be impacted in approximately 10 years. The southern edge of the cemetery is protected by horizontal and vertical accretion. As a result, conservation resources should be concentrated on the northern edge of the cemetery.  相似文献   
173.
Eight hundred forty children (435 girls) enrolled in full-time, center-based child care participated in the study. Children ranged in age from 10 to 70 months. Sixty-six percent of the children were European American, the remainder African American. Children's play activities and cognitive activities as well as their relationships with caregivers were observed within the child care setting. The study tested the prediction that variation in children's cognitive activities could be directly and indirectly explained by child care quality, positive social interaction with teachers, and children's play activities and attachment security with their child care teachers. The prediction was examined and at least partially supported in eight subsamples of infant-toddler and preschool age European American and African American children in subsidized and nonsubsidized child care. Specifically, in seven of the eight subsamples, 15 to 30% of the variability in children's cognitive activities could be predicted from positive social interaction with teachers, attachment security, and participation in creative play activities.  相似文献   
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This study was designed to identify how objectives influence the organization of the information recalled from text. Three hypotheses were investigated: (1) that objectives affect the sequence of attention to information in text, (2) that they affect the sequence in which information is rehearsed during a review period, or (3) that they serve as a set of cues at retrieval. One hundred college students read objectives either before or after reading a passage (varying the opportunity for objectives to affect the sequence of attention). They then either had or did not have a review period (varying the opportunity to use objectives to sequence rehearsal and also varying the presence of the objectives in memory at the time of retrieval). One hundred more students read the passage in control conditions with objectives available throughout the reading or with no objectives available. Results showed that students given objectives after reading but before a review period had more clustering by objectives in free recall than did those who never saw objectives, supporting the hypothesis that organization by objectives occurs during rehearsal. No evidence was found to support the notion that organization by objectives occurs during encoding or retrieval phases.  相似文献   
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New electronic opportunities for scientific communication, and changes in how scientists use journals, are prompting a complete re-evaluation of the roles of scientific journals and of scholarly societies like the APS.  相似文献   
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