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11.
Within the Canadian context, the physical activity levels of children and youth in the after school time period has become a source of public health concern. We argue that this concern is informed by broader public health crises, in particular the ‘global obesity epidemic’ and the closely related ‘global pandemic of physical inactivity', and that these so-called ‘crises’ operate as part of a discursive regime that serves to justify after school interventions aimed at increasing the physical activity practices of children and youth. Although the objectives of such interventions are seemingly well intentioned, we suggest that such interventions nonetheless harbor difficult to discern, but potentially pernicious consequences, for the communities in which they are implemented. We focus our attention on the place-specific effects of one Public Health Agency of Canada-funded after school physical activity intervention – After the School Bell Rings (ASBR) – that was implemented in the mostly Indigenous, northern community of Placid, Manitoba. Based on a critical analysis of the ASBR program itself, along with interviews and focus groups with children, parents and recreation providers (n?=?10) from the community of Placid, we contend that the ASBR serves to govern Indigenous recreation at a distance. We argue that when implemented in the place-specific context of Placid, the ASBR functions as part of a broader governmental assemblage composed of loosely connected discourses, institutions, socio-structural conditions and individuals that, when assembled, ultimately serve to govern geographically and culturally distinct communities. We conclude by suggesting that the objectives of broad-based health interventions, such as the goal of increasing after school physical activity levels, should not be universally implemented across diverse locales, but need to account for the diverse, place-specific priorities and needs of the communities into which they are implemented.  相似文献   
12.
The trajectory of the clubhead close to ball impact during the golf swing has previously been shown to be planar. However, the relationship between the plane orientation and the orientation characteristics of the clubhead at ball impact has yet to be defined. Fifty-two male golfers (27 high skilled, 25 intermediate skilled) hit 40 drives each in an indoor biomechanics laboratory. This study successfully fitted the trajectory of the clubhead near impact to an ellipse for each swing for players of different skill levels to help better explain this relationship. Additionally, the eccentricities of the ellipses were investigated for links to skill level. The trajectory of the clubhead was found to fit to an ellipse with RMSE of 1.2 mm. The eccentricity of the ellipse was found to be greater in the high-skilled golfers. The club path and angle of attack generated from the ellipse fitted clubhead trajectory were found to have a normalised bias-corrected RMSE of 2% and 3%, respectively. A set of “rule of thumb” values for the relationship between the club path, angle of attack and delivery plane angle was generated for use by coaches.  相似文献   
13.
Web sites are increasingly used by academic libraries to promote key services and collections to teaching faculty. This study analyzes the content, location, language, and technological features of fifty-four academic library Web pages designed especially for faculty to expose patterns in the development of these pages.  相似文献   
14.
We first present in this paper an analytical view of heuristic retrieval constraints which yields simple tests to determine whether a retrieval function satisfies the constraints or not. We then review empirical findings on word frequency distributions and the central role played by burstiness in this context. This leads us to propose a formal definition of burstiness which can be used to characterize probability distributions with respect to this phenomenon. We then introduce the family of information-based IR models which naturally captures heuristic retrieval constraints when the underlying probability distribution is bursty and propose a new IR model within this family, based on the log-logistic distribution. The experiments we conduct on several collections illustrate the good behavior of the log-logistic IR model: It significantly outperforms the Jelinek-Mercer and Dirichlet prior language models on most collections we have used, with both short and long queries and for both the MAP and the precision at 10 documents. It also compares favorably to BM25 and has similar performance to classical DFR models such as InL2 and PL2.  相似文献   
15.
This study tested competing predictions about the implications of Internet use for traditional inequities in social support availability. Using survey data collected as part of the Pew Internet and American Life Project, inequities in social support availability stemming from demographic and network-related factors were examined among non-users, Internet users, and Internet users who also participated in a social network site (SNS). The results offered evidence consistent with the social compensation perspective. Traditional inequities in support availability related to age, race, and total network size persisted among respondents who did not use the Internet, but were less evident or absent among Internet users and/or Internet users who participated in an SNS. Using the Internet to connect with others appeared to be an important mechanism through which inequality in support availability was mitigated.  相似文献   
16.
17.
David G. Clark and Earl R. Hutchinson, Mass Media and the Law: Freedom and Restraint (Wiley-Interscionco, $12.95)

John M. Kittross and Konnoth Harwood, Free & Fair: Courtroom Access and the Fairness Doctrino (Journal of Broadcasting, Temple University, $3.95)

Paul W. MacAvoy's The Crisis of the Regulatory Commissions: An Introduction to a Current Issue of Public Policy (Norton, $5.95; paper, $2.95)

Eric Moon, Book Selection and Consorship in the Sixties (Hawker, $10.95)

Edward De Grazia's Censorship Landmarks (Hawker, $19.75)  相似文献   
18.
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is quickly becoming a critical tool in the field of art conservation. This technique provides high-resolution spatial maps of both inorganic and organic components located within cross-sectional samples collected from works of art. With recent advances in surface analysis, ToF-SIMS can now be used to identify specific amino acids present in protein-containing materials as well as fatty acids in drying oils. For example, the detection of the ion fragment associated with the amino acid hydroxyproline can be used to confirm the use of animal glue in a paint sample. As an analytical technique, ToF-SIMS avoids the need for derivatization/silylation reagents, with no interference by the presence of pigments. Furthermore, the layered systems that are often encountered in historical paint samples remain intact throughout the analytical procedure. This allows for the co-localization of organic and inorganic species in specific layers (e.g. egg yolk paint atop a glue ground). Because of this ability to localize the analytical signal to approximately 6?µm or less, the mass spectral information can be used to produce mass-resolved and spatially-resolve images which can be correlated to previous studies of the same samples. In this study, ToF-SIMS was used to analyze a paint cross section obtained from a painting attributed to Raphael, and another from a painting by the Sienese artist Matteo di Giovanni.  相似文献   
19.
Abstract

Previous studies on the kinematics of the golf swing have mainly focused on group analysis of male golfers of a wide ability range. In the present study, we investigated gross body kinematics using a novel method of analysis for golf research for a group of low handicap female golfers to provide an understanding of their swing mechanics in relation to performance. Data were collected for the drive swings of 16 golfers using a 12-camera three-dimensional motion capture system and a stereoscopic launch monitor. Analysis of covariance identified three covariates (increased pelvis–thorax differential at the top of the backswing, increased pelvis translation during the backswing, and a decrease in absolute backswing time) as determinants of the variance in clubhead speed (adjusted r 2 = 0.965, P < 0.05). A significant correlation was found between left-hand grip strength and clubhead speed (r = 0.54, P < 0.05) and between handicap and clubhead speed (r = ?0.612, P < 0.05). Flexibility measures showed some correlation with clubhead speed; both sitting flexibility tests gave positive correlations (clockwise: r = 0.522, P < 0.05; counterclockwise: r = 0.711, P < 0.01). The results suggest that there is no common driver swing technique for optimal performance in low handicap female golfers, and therefore consideration should be given to individual swing characteristics in future studies.  相似文献   
20.
Pornography use is often associated with less-progressive sex-role attitudes, such as endorsement of a sexual double standard between heterosexual partners, but the process by which this relationship occurs is still largely unexamined. The present study was conducted to examine how perceptions about pornography may play a role in the relationship between pornography use and sex-role attitudes. Perceived general acceptance and perceived influence of pornography on most people partially mediated the relationship between pornography use and sex-role attitudes. The more participants reported using pornography, the more they believed pornography was generally accepted and had a positive influence; however, conversely to what was hypothesized, the more positive they perceived pornography’s influence, the less likely they were to report sex-role attitudes that endorse a sexual double standard.  相似文献   
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