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Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The seismic attenuation in concrete has seldom been studied, although it is an important parameter for survey design. In this paper, the seismic Q factor is estimated from data measured at the Carillon dam. Three methods were used for this study: amplitude decay yielding a value of 5.1 ± 1.6, spectral ratio giving a value of 8.3 ± 3.5, and a value of 7.5 ± 14.9 was obtained from the rise-time technique. These values are weak compared with what is generally observed in rocks, and slightly lower than values obtained on laboratory concrete samples. However, the average P wave velocity measured on the investigated area is 4081 ± 95 m·s[sup –1] , an indication of the good quality of the material. Consequently, this strong attenuation could be attributed on one hand to energy loss, and on the other hand to scattering caused by the intrinsic cement–aggregate composition of concrete. It is also possible that an inadequate sensor coupling had the effect of reducing the observed Q value. Key words: seismic attenuation, concrete dams, microseismic monitoring, coupling.Paramètre important pour la planification de levés sismiques, l'atténuation sismique a été peu étudiée dans les bétons. Dans cet article, le facteur de qualité sismique Q est évalué au barrage de Carillon selon les méthodes du rapport des amplitudes, du rapport des spectres d'amplitude et du temps de montée. Les mesures obtenues sont respectivement de 5,1 ± 1,6, de 8,3 ± 3,5 et de 7,5 ± 14,9. Ces valeurs sont faibles en regard de ce qui est généralement observé dans les roches, et légèrement plus faibles que des valeurs mesurées sur des bétons en laboratoire. Par ailleurs, le béton de la partie du barrage auscultée présente une vitesse d'onde P moyenne de 4081 ± 95 m·s[sup –1] , indiquant une bonne qualité du matériau. En conséquence, la forte atténuation pourrait être attribuable d'une part à la perte de l'énergie sismique sous forme de friction, et d'autre part à une atténuation de diffusion occasionnée par la composition ciment-granulat intrinsèque du béton. Il est également possible qu'un couplage inadéquat des capteurs ait pour effet de réduire la valeur observée de Q. Mots clés : atténuation sismique, barrages en béton, auscultation microsismique, couplage. [ABSTRACT FROM AUTHOR]

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The current low level of physical activity among Canadians is a dominant public health concern. Accordingly, a clear understanding of physical activity patterns and trends is of paramount importance. Irregularities in monitoring, analysis, and reporting procedures create potential confusion among researchers, policy-makers, and the public alike. The purpose of this paper is to consolidate reported findings and provide a critical assessment of the physical activity surveillance procedures, analytical practices, and reporting protocols currently employed in Canada to provide insights for accurate and consistent interpretation of data, as well as recommendations for future surveillance efforts.

This paper summarizes available information on patterns of physical activity, their determinants and consequences, and the results of various interventions designed to increase the physical activity of Aboriginal peoples in Canada and the United States. There is a paucity of national data on this issue for Aboriginal peoples. The most recent data, from the First Nations Regional Longitudinal Health Survey of 2002-2003, indicate that 21% of adults (27% of men, 15% of women) were engaging in at least 30 min of moderate to vigorous physical activity on 4 d/week or more. The present paper highlights the unique challenges this group faces, underlining the need to integrate collective knowledge regarding how much physical activity is required for Aboriginal Canadians, and how this activity should be accomplished, to promote and maintain health. Efforts are currently underway to tailor Canada's physical activity guide for First Nations, Inuit, and Métis. Future research among Aboriginal groups should examine the minimal and optimal levels of physical activity required to achieve health benefits.

The aim of this review is to provide a scientific update on evidence related to the biological and psycho-social health benefits of physical activity in school-aged children and youth. To accomplish this aim, the first part of the paper reviews existing physical activity guidelines for school-aged children and youth, with an emphasis placed on how Canada's guidelines compare and contrast with those of other countries and organizations. The paper then provides an overview of physical activity levels of Canadian children and youth, which indicates that few Canadian youngsters meet current physical activity recommendations. The next section of the paper summarizes the literature that informs how much physical activity is required to promote health and well-being in children and youth. The paper then provides suggestions on modifications that could be made to Canada's physical activity guidelines for children and youth. Specifically, consideration should be given to setting both minimal (>/=60 min/d) and optimal (up to several hours per day) physical activity targets. The final section identifies future research needs. In this section, a need is noted for comprehensive dose-response studies of physical activity and health in the paediatric age group.

Physical activity guidelines offer evidence-based behavioural benchmarks that relate to reduced risk of morbidity and mortality if people adhere to them. Essentially, the guidelines tell people what to do, but not why and how they should do it. Thus, to motivate adherence, messages that translate guidelines should convey not only how much physical activity one should attempt and why it is recommended, but also how to achieve such a recommendation. Canada's physical activity guides exemplify how guidelines can be translated. This paper (i) provides a brief overview of the challenges encountered in creating the existing guides and (ii) highlights important practical issues and empirical evidence that should be considered in the future when translating guidelines into messages and disseminating these messages. We draw on the successes of past efforts to translate the goals of physical activity guidelines and on recent literature on messages and media campaigns to make recommendations. Information to motivate people to move toward the goals in physical activity guidelines should be translated into a set of messages that are informative, thought provoking, and persuasive. These messages should be disseminated to the public via a multi-phase social-marketing campaign that is carefully planned and thoroughly evaluated.

This paper provides a brief overview of the epidemiological data regarding Canadians with physical disabilities, with a particular emphasis on health status. A literature review is then presented, focusing on activity levels and the physiological and health-related quality of life benefits of activity for people with four different physical disabilities (arthritis, fibromyalgia, spinal cord injury, and multiple sclerosis). The unique physical activity barriers faced by people with physical disabilities are discussed. The paper concludes with recommendations for the development of a physical activity guide for Canadians with physical disabilities.

The accurate measurement of habitual physical activity is fundamental to the study of the relationship between physical activity and health. However, many physical activity measurement techniques produce variables accurate to only the day level, such as total energy expenditure via self-report questionnaire, pedometer step counts, or accelerometer measurements of minutes of moderate to vigorous physical activity. Monitoring technologies providing more detailed information on physical activity and inactivity behaviour can now be used to explore the relationships between health and movement frequency, intensity, and duration more comprehensively. This paper explores the activity-inactivity profile that can be acquired through objective monitoring, with a focus on accelerometry. Using previously collected objective data, a detailed physical activity profile is presented and case study examples of data utilization and interpretation are provided. The rich detail captured through comprehensive profiling creates new surveillance and study possibilities and could possibly inform new physical activity guidelines. Data are presented in various formats to demonstrate the dangers of misinterpretation when monitoring population adherence to Canada's physical activity guidelines. Recommendations for physical activity-inactivity profiling are provided and future research needs identified.

The purpose of this paper is to examine the reach of different versions of Canada's physical activity guide (CPAG) and their impacts, including immediate effects (awareness, knowledge, beliefs, future intention to be active, first steps towards behavioural change) and population levels of physical activity. The analysis is based on eligible adults aged 18 years and older (n = 8892) included in the 2003 Physical Activity Monitor (PAM) survey. The 2003 PAM was a cross-sectional, telephone interview of a representative population sample. Secular trends of Canadians aged 12 years and older were examined, using representative samples from the National Population Health and Canadian Community Health Surveys. Unprompted recall of any guidelines for physical activity was very low (4%), whereas prompted recall of the CPAG was higher (37%). Unprompted and prompted recall were higher among women and high-income earners, and increased with level of education. Behaviours associated with "seeking information" and "initiating action" were associated with unprompted and prompted recall. Beliefs about the benefits of physical activity and intention to be active were also associated with prompted recall. Unprompted CPAG recall, knowledge about the amount of activity required to meet the CPAG, intention to be active, "seeking information", and "initiating action" were associated with being "sufficiently active". The CPAG is an appropriate set of public health guidelines or recommendations around physical activity. The low unprompted recall rate points to the need for a coordinated, well-funded approach to communication of these guidelines, involving governmental and non-governmental partners and intermediaries in municipalities, schools, workplaces, and the recreational, public health, and health-care systems.

This historical background paper chronicles the major events leading to the development of Canada's physical activity guides (for children, youth, adults, and older adults). The paper outlines the process and the steps used, including information (where applicable) regarding national partners, project administration, Health Canada communications, product development, endorsement, distribution and implementation, collateral activities, media relations and evaluation framework. Brief summaries of the science that led to the recommended guidelines are included. The paper also summarizes the various physical activity guide assessment and evaluation projects and their findings, particularly as they relate to research carried out on Canada's physical activity guides for children and youth (and the associated support resources).

This article summarizes the main findings from the papers included in this journal supplement. It consolidates the evidence currently available to inform and advance the development of physical activity guidelines for Canadians, and it highlights the specific needs of various population subgroups. The challenges of translating guideline information into effective and persuasive physical activity messages, of campaigns to disseminate messages and of related evaluations are underlined. Recommendations on how to proceed are based on the evidence base provided by this series of papers; the immediate next steps mandated by this initiative are outlined and priorities for future research are indicated.

Canadian public health messages relating to physical activity have historically focused on the prescription of purposeful exercise, most often assessing leisure-time physical activity (LTPA). Although LTPA contributes to total energy expenditure (TEE), a large part of the day remains neglected unless one also considers the energy expended outside of purposeful exercise. This paper reviews the potential impact of incidental (non-exercise or non-purposeful) physical activity and lifestyle-embedded activities (chores and incidental walking) upon TEE and indicators of health. Given that incidental movement occurs sporadically throughout the day, this form of energy expenditure is perhaps most vulnerable to increasingly ubiquitous mechanization and automation. The paper also explores the relationship of physical inactivity, including sleep, to physical activity, TEE, and health outcomes. Suggestions are provided for a more comprehensive physical activity recommendation that includes all components of TEE. Objective physical activity monitors with time stamps are considered as a better means to capture and examine human movements over the entire day.

The Canadian Society for Exercise Physiology (CSEP), in partnership with Health Canada and others, released Canada's first physical activity guide for adults in 1998, with specific versions for older adults in 1999 and for children and youth in 2002. Research in the physical activity sciences (e.g., basic science, behavioural assessment, dose-response relationships, epidemiology, health messaging, physical activity measurement) has advanced rapidly since these publications. A detailed review of relevant current research is thus required, to assess whether the existing guidelines and resulting guides need revision or renewal. This introductory paper provides a brief chronology of events leading to the preparation of this journal supplement, including a statement of purpose and an overview of organization and content. A brief discussion of the purpose of the physical activity guidelines and guides, intended biological, psychological, and behavioural outcomes, and the way in which guidelines relate to on-going measurement and surveillance is provided as a context for the papers that follow.