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81.
Musculoskeletal disorders (MSDs) have been recognized as a serious hazard to the health and safety of sonographers. Recommendations have been made on ways to reduce and prevent the frequency and severity of these disorders. The purpose of this study was to ascertain the impact ergonomics has had on the prevalence of MSDs among cardiac sonographers. Three hundred randomly selected Registered Diagnostic Cardiac Sonographers were surveyed. Eighty-one respondents completed the survey. The majority of the sample population was female with an average age of 40 and job tenure between 6-15 years. Ninety percent of respondents reported musculoskeletal pain/discomfort while scanning. Seventy-three percent of respondents perceived a need for ergonomic interventions. The majority of respondents were aware of previously recommended ergonomic interventions and had implemented what was feasible. Still, the experience of pain and discomfort, and incidence of MSDs remains exceptionally high for this occupation. It appears that recommended ergonomic interventions have not had a significant impact on improving the health and safety of cardiac sonographers. 相似文献
82.
A projective (2n,n,λ,1)-design is a set of n element subsets (called blocks) of a 2n-element set V having the properties that each element of V is a member of λ blocks and every two blocks have a non-empty intersection. This paper establishes existence and non-existence results for various projective (2n,n,λ,1)-designs and their subdesigns. 相似文献
83.
This paper examines the theoretical and empirical basis for common rank-orderings of occupational roles by raters throughout the world. From an illustrative comparison of occupational stratification in Australia and the United States we conclude tentatively that (1) commonalities in the socioeconomic characteristics of occupational roles provide the basis for interplace consistencies in “prestige” scores, (2) the structure of occupational mobility in the U.S. and Australia is largely similar, (3) this similar structure of occupational stratification manifests a common socioeconomic process which defines a (the?) major component of occupational mobility in capitalist, industrial (only?) societies. We infer that “prestige” scores for occupations are fallible estimates of the socioeconomic statuses of occupation, within the context of mobility processes in (at least) the U.S. and Australia. 相似文献
84.
85.
Ellickson PL Bird CE Orlando M Klein DJ McCaffrey DF 《Journal of health and social behavior》2003,44(4):525-535
This paper examines the links between individual adolescent smoking behavior and actual and perceived smoking behavior in the individual's school cohort. We hypothesized that students enrolled in schools with higher smoking prevalence among students in their grade are more likely to smoke subsequently. We also expected perceived school-level prevalence of smoking to have a greater impact than actual prevalence because the former is a more direct measure of perceived norms. Adjusting for demographics, actual school-level prevalence at baseline (grade 7) was strongly associated with smoking frequency one year later. However, the association disappeared after adjusting for individual smoking frequency at baseline. School-level prevalence did not moderate the association between individual's baseline and subsequent smoking frequency. Perceived prevalence of smoking among grade 8 students and two measures tapping the behavior of smaller peer groups--cigarette offers and exposure to friends and other peers who smoke--were associated with increased risk of smoking. 相似文献
86.
Wise PM 《Science of aging knowledge environment : SAGE KE》2003,2003(22):PE13
The brains of aged rodents exhibit decreased neurogenesis as compared to those of young adult rodents. Basal neurogenesis has previously been shown to increase in the young adult rodent brain upon the administration of growth factors. However, it is unknown whether similar treatment can affect this process in the aging brain. A recent paper published in the June 2003 issue of the journal Aging Cell reveals that two growth factors can stimulate neurogenesis in aged mice. This result raises the possibility that similar treatments may be used in humans to help maintain normal brain function in old age. 相似文献
87.
Recent meta-analyses and experimental designs of batterer program evaluations suggest little or no program effect. This finding may be compromised by a variety of analytical issues. Instrumental variable analysis addresses some of these issues, especially the relationship of program dropout to batterer reassault. This method of analysis was, therefore, used to test for program effect in a multi-site evaluation. The sites were three well-established batterer programs using a gender-based, cognitive-behavioral approach (n = 640). Completing a batterer program reduced the likelihood of reassault by 44% to 64%, depending on the specification used. Completing a 3-month program appeared to be as effective as completing a 5 1/2- or 9-month program. This moderate effect is an accomplishment considering the problems associated with the program participants and the inconsistency in the criminal justice system at the research sites. The findings remain tentative because of weak instrumental variables for reassault, but do confirm the need for more complex analyses of program effect. 相似文献
88.
Jones J Ward M Wellman N Hall J Lowe T 《Journal of psychosocial nursing and mental health services》2000,38(12):10-20
1. Nursing observation is a key component of psychiatric inpatient nursing care. 2. Patients' experiences of being observed are strongly influenced by the attitudes and behaviors of the observing nurses. 3. Patients prefer to be observed by nurses they know and who talk to them. 相似文献
89.
The aim of this work is to be a useful instrument for helping finance practitioners on the selection of suitable mutual fund portfolios. The portfolio selection problem is characterized by imprecision and/or vagueness inherent in the required data and more generally, in the context where investors have to make decisions. In order to mitigate these problems, a three stage model has been proposed based on a multi-index model and considering several market scenarios described in an imprecise way by an expert. The proposed fuzzy model allows the Decision Maker to select, by means of an outranking method, a suitable portfolio taking into account the uncertainty related to the market scenarios and the imprecision and/or vagueness associated with the model data. 相似文献
90.