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This paper examines suspended sediment concentration and stream discharge during freshet in three small sub-boreal forest streams (<1.5 m in width) in the central interior of British Columbia for 1 year prior to (1996) and for 5 years following forest harvesting (1997-2001). Harvesting prescriptions in a 20-m strip beside one stream required complete removal of merchantable timber (>15 cm diameter at breast height (DBH) for pine and >20 cm for spruce), while all stems <30 cm DBH were retained beside a second stream. A third stream remained unharvested as a control. The two riparian treatments were prescribed to test the efficacy of current British Columbia legislation that allows for varying amounts of riparian retention as best management practices for the management of windthrow. Both treated watersheds were clear-cut harvested (approximately 55% removal) in January 1997, and in the following year, temporary access roads were deactivated, including two stream crossings in the low-retention watershed. An increase in peak snowmelt and total freshet discharge was first noted in the second spring following harvest in both treatments and remained above predicted in all subsequent years. Suspended sediment also increased during freshet following harvest but returned to levels at or below preharvest predictions within 3 years or less in the high-retention watershed. [ABSTRACT FROM AUTHOR]

Hydrogeological models need to be supported by a clear understanding of the subsurface geology to provide effective assessment, flow modelling, or management of groundwater regimes. This paper illustrates how geophysical and sedimentological data can be used to significantly improve watershed-scale hydrostratigraphic models by advancing our understanding of the subsurface through regional hydrogeological investigations in the Greater Toronto Area. The example of a 3 km shallow seismic reflection survey that traverses a buried channel within Bowmanville Creek watershed. Oak Ridges Moraine, Ontario, illustrates a basis for linking geophysical and sedimentological properties to regional hydrostratigraphic parameters. Seismic reflection methods plus seismic stratigraphy and a well-constrained three-dimensional geological framework have helped to (i) identify regional hydrostratigraphic units, (ii) define properties and trends of these units-facies, (iii) improve depositional models that assist hydrogeological analysis, and (iv) establish a hydrostratigraphic framework within a watershed. The extent, proportions, boundaries, and variation in internal properties of major hydrostratigraphic units could be identified to greater than 100 m depth. Geostatistical analysis of seismic amplitudes was used to provide a quantitative measure of heterogeneity in a glaciofluvial aquifer with inadequate parameter support. Benefits to engineering practice include improved siting of monitors and tests from portrayal of the spatial organization, geometry, and variability of hydrostratigraphic units based on sedimentary architecture and environments of deposition. Hydrogeological modelling can be improved with better knowledge of the geometry of aquifers and aquitards and grid-cell boundaries that correspond with the defined sediment boundaries that control properties. [ABSTRACT FROM AUTHOR]

To investigate the utility of short visits to seabird colonies to gauge nestling growth performance and diet, in four consecutive years from 1995 to 1998, the paper measures the nestling development and diet of rhinoceros auklets or cerorhinca monocerata at three colonies in British Columbia: Seabird Rocks, Triangle Island and SGaang Gwaii (Anthony Island).

An estimated 2300 people became seriously ill and 7 died from exposure to microbially contaminated drinking water in the town of Walkerton, Ontario, in May of 2000. The severity of this drinking water disaster resulted in the Government of Ontario calling a public inquiry by Mr. Justice Dennis O'Connor to address the cause of the outbreak, the role, if any, of government policies in contributing to this outbreak, and ultimately, the implications of this experience on the safety of drinking water across the province of Ontario. This paper summarizes relevant evidence presented at the inquiry by the expert panel together with Justice O'Connor's findings addressing the circumstances of the outbreak. These findings are reviewed in relation to the published causes of previous waterborne disease outbreaks that have been reported elsewhere in developed countries. The circumstances surrounding the Walkerton tragedy are an important source of knowledge for those concerned with providing safe drinking water to the public. Although some circumstances are obviously specific to this epidemic, others echo common themes in waterborne outbreaks that have occurred before. These common themes suggest the need for attention to broad issues of drinking water safety in addition to the individual specific details that often command attention. Key words: waterborne disease, Escherichia coli O157:H7, Campylobacter jejuni, Cryptosporidium, Giardia, multiple barriers, health risk.Environ 2300 personnes sont devenues gravement malades et sept personnes sont décédées à la suite d'une exposition à de l'eau potable contaminée par voie microbienne dans la ville de Walkerton, en Ontario, en mai 2000. La gravité de ce désastre d'eau potable a fait que le gouvernement de l'Ontario a lancé une enquête publique, menée par M. le juge Dennis O'Connor, visant à déterminer la cause de cette éclosion, la contribution, s'il y a en une, des politiques gouvernementales à cette éclosion et, en bout de ligne, les répercussions de cette expérience sur la salubrité de l'eau potable partout en Ontario. Cet article résume les preuves pertinentes présentées à l'enquête par le panel d'experts et les conclusions du juge O'Connor sur les circonstances de cette éclosion. Ces conclusions sont revues à la lumière des causes publiées touchant les éclosions antérieures de maladies hydriques qui ont été rapportées ailleurs dans les pays développés. Les circonstances entourant la tragédie de Walkerton sont une source importante de connaissances pour les compagnies fournissant de l'eau potable salubre au public. Bien que certaines circonstances sont évidemment spécifiques à cette épidémie, d'autres font penser à des thèmes communs aux éclosions hydriques survenues auparavant. Ces thèmes communs suggèrent le besoin de porter attention aux grandes questions de la sécurité de l'eau potable en plus des détails uniques spécifiques qui doivent souvent être examinés. Mots clés : maladie hydrique, Escherichia coli O157:H7, Campylobacter jejuni, Cryptosporidium, Giardia, barrières multiples, risque pour la santé. [Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

During the past decade, composite steel-free deck bridges came to reality in Canada through the construction of five bridges. The new structural system enables the construction of a concrete deck that is totally devoid of all internal steel reinforcement. Traditionally, reinforced concrete bridge decks are designed to sustain loads in flexure. The steel-free deck bridge system develops internal compressive forces "internal arching," which leads to failure by punching shear at substantially higher loads than the flexural design load. The fibre-reinforced concrete deck is usually attached to the steel girders through flexible shear connectors. These steel girders are transversely tied together by steel straps and cross frames. In this paper, the concept of the new bridge system is briefly discussed. The generations of the deck slabs are introduced. Brief outlines of the bridges built to date with this new technology are presented. A three-dimensional finite element model is then proposed to study the behaviour of the main structural component of the new system. The model is verified against previous experimental results and is used to perform a parametric study on some aspects which are thought to significantly affect the behaviour of the new steel-free deck bridge system.Key words: bridges, composite girders, finite element method, steel-free deck, steel straps.Durant la dernière décennie, les ponts à tablier composé sans acier sont devenus réalité au Canada grâce à la construction de cinq ponts. Ce nouveau système structural permet la construction d'un tablier en béton qui est complètement dépourvu de tout renforcement interne en acier. Traditionnellement, les tabliers de pont en béton armé sont conçus afin de supporter des charges en flexion. Le système de tablier de pont sans acier développe des forces internes en compression « cintrage interne » et résulte en une rupture par poinçonnement en cisaillement pour une charge substantiellement plus grande que les charges en flexion de conception. Le tablier en béton renforcé de fibres est habituellement attaché aux poutres d'acier à l'aide de connexions de cisaillement flexibles. Ces poutres d'acier sont attachées ensemble transversalement à l'aide de liens d'acier et de contreventements. Dans cet article, le concept de ce nouveau système est brièvement discuté. Les générations des tabliers en dalles sont introduites. Un bref aperçu des ponts construits à ce jour avec cette nouvelle technologie est présenté. Un modèle par éléments finis tirdimensionnel est par la suite proposé afin d'étudier le comportement des composants structurels principaux du nouveau système. Le modèle est confronté aux résultats expérimentaux obtenus par d'autres dans le passé. Ensuite, il est utilisé afin de performer une étude paramétrique sur quelques aspects qui sont suspectés d'affecter de façon significative le comportement de ce nouveau système de tablier de pont sans acier.Mots clés : ponts, poutres composées, méthode par éléments finis, tablier sans acier, liens d'acier.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

The hydraulic conductivity of six compacted tills from northern Quebec with different grain-size distributions has been studied in saturated conditions in the laboratory. The results show that compaction conditions play an important role in hydraulic conductivity. When considering the hydraulic conductivities of specimens compacted at degrees of saturation greater than the optimum, there is a good correlation with the content of clay-size particles. This paper provides a good practical tool for evaluating preliminary hydraulic conductivity values of compacted tills from northern Quebec on the basis of their grain-size distribution and compaction conditions.Key words: till, hydraulic conductivity, grain-size distribution, compaction conditions.La conductivité hydraulique de six tills du nord québécois présentant des granulométries différentes a été étudiée en conditions saturées, en laboratoire. Les résultats montrent que les conditions de compactage jouent un rôle important dans la conductivité hydraulique qui en résulte. Lorsque l'on considère les conductivités hydrauliques mesurées sur des échantillons compactés à des degrés de saturation plus élevés que celui à l'optimum, on obtient une bonne corrélation avec le pourcentage de particules de dimensions argileuses. Cet article fournit donc un bon outil pratique pour une évaluation préliminaire de la conductivité hydraulique des tills du nord québécois sur la base de leur granulométrie et des conditions de compactage.Mots clés : till, conductivité hydraulique, granulométrie, conditions de compactage. [ABSTRACT FROM AUTHOR]

This paper concerns the petrogenesis of the 504 ± 3 Ma Mont Chagnon massif, the southern extension of the Orford ophiolite in the Quebec Appalachians. The evolution of this massif is summarized in three stages marked by different magmatic series. In the Late Cambrian, the onset of southeastern subduction of the Iapetus basin generated an immature oceanic island arc made up of light rare-earth-element-depleted tholeiites, now preserved in the massif as a portion of the intrusive crustal unit, the dyke complex, and part of the lower volcanic unit. A phase of arc splitting, and concomitant partial erosion of the crustal section, was shortly followed by the eruption of rhyolite genetically related to felsic and low-Ti dykes, and trondhjemite. The geochemistry of these magmas bear some similarities with boninitic series. We believe these liquids derived from the partial melting of the Iapetus amphibolitized oceanic crust, with that of its Laurentian-derived sediments and nearby peridotite, either found as a trapped sliver above the subducting slab or as the slab itself. The final stage, preserved in the massif as a part of the intrusive section, the upper volcanic rocks, and the late-stage dykes, represents the back-arc opening. An ocean-island component is involved in the back-arc related petrogenetic processes, producing magmas with compositions intermediate between arc tholeiites and enriched back-arc basin basalts. This is the first report that the Iapetus basin was locally closing as early as Late Cambrian in the southern Quebec area.Cet article traite de la pétrogenèse du massif du mont Chagnon, daté à 504 ± 3 Ma, qui est l'extension méridionale de l'ophiolite d'Orford dans les Appalaches du Québec. L'évolution de ce massif est résumée en trois étapes déterminées par des suites magmatiques différentes. Au Cambrien tardif, le début de la subduction vers le sud-est d'Iapetus a crée un arc insulaire océanique immature composé de tholéiites appauvries en terres rares légères, maintenant préservées dans le massif en tant qu'une portion de l'unité crustale intrusive, le complexe de dykes et une partie de l'unité volcanique inférieure. Une phase de division de l'arc, et l'érosion partielle concomitante de la section de la croûte, a été suivie de près par l'éruption de rhyolite, génétiquement reliée aux dykes felsiques et à ceux faibles en Ti, de même qu'à la trondhjémite. La géochimie de ces magmas comporte des similitudes avec les séries boninitiques. Nous croyons que ces liquides proviennent de la fusion partielle de la croûte amphibolitisée d'Iapetus, de ses sédiments dérivés du craton Laurentia et de la péridotite avoisinante, qui se trouvent soit coincés en tant qu'écaille au-dessus de la lithosphère en subduction ou soit en tant que lithosphère subductée elle-même. L'étape finale, préservée dans le massif en tant qu'une partie de la section intrusive, les roches volcaniques supérieures et les dykes tardifs, représente l'ouverture de l'arrière-arc. Une composante d'île océanique est impliquée dans les processus pétrogénétiques reliés à l'arrière-arc, produisant des magmas dont les compositions sont intermédiaires entre les tholéiites d'arc et les basaltes enrichis de bassins d'arrière-arc. Ceci est le premier rapport qu'Iapetus se refermait localement aussi tôt que le Cambrien tardif dans le sud du Québec.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Linear developments such as roads, seismic lines, and pipeline rights-of-way are common anthropogenic features in the boreal forest of Alberta. These features may act as barriers to the movement of threatened woodland caribou, Rangifer tarandus caribou. Seismic lines were not barriers to caribou movements, whereas roads with moderate vehicle traffic acted as semipermeable barriers to caribou movements. Twenty-two adult female and 1 adult male woodland caribou were captured and collared on February 17–19, 1998. Each caribou was fitted with a global positioning system collar. The greatest barrier effects were evident during late winter, when caribou crossed actual roads 6 times less frequently than simulated road networks. Semipermeable barrier effects may exacerbate functional habitat loss demonstrated through avoidance behavior. Caribou may cross roads less frequently than expected for a number of reasons, including an aversion to the physical barrier presented by a road and associated forest opening, vehicle traffic, or predation by humans. The effects of habitat fragmentation through habitat loss, avoidance, and the semipermeable barrier effects of roads should be considered in developing strategies to maintain woodland caribou populations in Alberta. Roads that act as semipermeable barriers to caribou movements may make the presence of caribou more predictable in space and time, and hence compromise the "spacing out" strategy that caribou adopt to reduce predation. The approach we have outlined in this paper is a useful method to quantify the effects of human developments acting as semipermeable barriers to animal movements and should be considered in the development of animal-movement models.

Highlights the Peptide Receptors: From Gene to Therapy, an international multidisciplinary symposium held in Montreal, Quebec from July 29 to August 2, 2001. Contents of the symposium; Sponsors of the symposium; List of papers presented in the symposium.

This paper reviews the factors and criteria for the design of new and the retrofitting of existing dry detention ponds to enhance removal of total suspended solids (TSS) from stormwater. Detention time is discussed as the most important factor affecting TSS removal. Two-stage facilities and multi-level outlet design are important means of enhancing TSS removal in dry ponds. Two dry ponds within the city of Edmonton were selected to evaluate their TSS removal. The level of expected TSS removal is low owing to the relatively short detention times for both ponds. Methods for retrofitting the dry ponds to enhance TSS removal are discussed.Key words: dry pond, stormwater, TSS removal, detention time, retrofitting.Cet article passe en revue les facteurs et critères de conception de nouveaux étangs de rétention, et de modification de ceux déjà existants, avec pour but d'améliorer la capacité d'enlèvement des substances solides totales en suspension (SST) contenues dans les eaux de ruissellement. Le temps de rétention est examiné en tant que facteur principal affectant l'enlèvement des SST. Les installations à deux étages et la conception de sorties multi-niveaux sont des procédés importants qui améliorent l'enlèvement des SST dans les étangs. Deux étangs de la Ville d'Edmonton ont été sélectionnés et leur capacité de rétention a été évaluée. Le niveau d'enlèvement des SST escompté est bas compte-tenu des temps de rétention relativement courts de ces deux étangs. Les méthodes de modification des étangs visant à améliorer l'enlèvement des SST sont examinées.Mots clés : étang, eaux de ruissellement, enlèvement des SST, temps de rétention, réajustement.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Highlights the Peptide Receptors: From Gene to Therapy, an international multidisciplinary symposium held in Montreal, Quebec in 2001. Topics discussed in the symposium; List of papers presented in the symposium.

This paper presents results from a teleseismic experiment conducted across the Hearne Province in south-central Alberta. Data from an array of nine portable broad-band seismographs deployed along a 500 km NW–SE array have been supplemented with recordings from two Canadian National Seismograph Network stations. P-wave delay times from 293 earthquakes have been inverted for upper-mantle velocity structure below the array. The recovered model reveals high velocities beneath much of the southern Hearne Province to depths of 200–250 km, which are interpreted as deep-seated lithospheric structure. Contrary to recent tectonic models, these results suggest that the Hearne lithosphere has remained intact. In particular, it appears unlikely that evidence for extensive, lower crustal melting derives from lithospheric delamination. However, the results admit the possibility that high mantle conductivity, as revealed in magnetotelluric studies, originates through small volumes of connected hydrous minerals or other conductive species introduced during subduction. Decreased upper-mantle velocities at the northern end of the Medicine Hat block also pose challenges for the interpretation of differential subsidence across the region which may manifest distant forcing due to more recent subduction. Multievent SKS-splitting analysis yields an average polarization direction that is broadly consistent with both the orientation of fossil strain fields, related to ~ 1.8 Ga NW–SE shortening, and North American absolute plate motion. Moho depth estimates from receiver functions are fairly uniform (~ 38 km) beneath northern stations but show crustal thickening (>40 km) within the Medicine Hat block to the south and are consistent with values from active-source profiling.Cette communication présente les résultats d'une expérience de téléséismicité effectuée à travers la province de Hearne dans le centre-sud de l'Alberta. Les données d'une station complexe de neuf sismographes, portatifs, à large bande, déployés le long d'un réseau NO–SE de 500 km ont été complétées avec des lectures de deux stations du réseau séismographique national (CNSN). Les temps d'arrivée de l'onde P provenant de 293 tremblements de terre ont été inversés pour déterminer la structure de vitesse de la croûte supérieure sous le réseau. Le modèle récupéré utilisé révèle des vitesses élevées sous une grande partie de la province de Hearne, jusqu'à des profondeurs de 200–250 km, que l'on interprète comme une structure lithosphérique à grande profondeur. Contrairement aux modèles tectoniques récents, ces résultats suggèrent que la lithosphère de Hearne soit demeurée intacte. En particulier, il semble peu probable que l'évidence pour une fusion extensive de la croûte inférieure découle d'une délamination lithosphérique. Toutefois, les résultats permettent d'entrevoir la possibilité qu'une conductivité mantellique élevée, telle que révélée par des études magnétotelluriques, origine à travers de petits volumes de minéraux hydratés reliés entre eux ou d'autres espèces minérales conductrices introduites au cours de la subduction. Des vitesses réduites dans la croûte supérieure à l'extrémité nord du bloc de Medicine Hat posent aussi des défis à l'interprétation de la subsidence différentielle à travers la région, ce qui pourrait être le reflet des contraintes distales en raison d'une subduction plus récente. Une analyse d'événements multiples de biréfringence des ondes SKS a donné une direction moyenne de polarisation qui concorde assez bien avec l'orientation des champs de contraintes fossiles reliée au raccourcissement NO–SE à ~ 1,8 Ga et au mouvement absolu de la plaque nord-américaine. Les estimations de la profondeur du Moho à partir de fonctions des récepteurs sont assez uniformes (~ 38 km) sous les stations nordiques mais elles présentent un épaississement de la croûte (>40 km ) à l'intérieur du bloc Medicine Hat vers le sud; ces estimations concordent avec les valeurs obtenues de profils de sources actives. [Traduit par la rédaction] [ABSTRACT FROM AUTHOR]

The preconsolidation pressure and overconsolidation ratio profiles are the most important factors related to the mechanical behaviour of clay deposits. They are interpreted on the basis of a limited number of laboratory tests, but the near-continuous information provided by the piezocone can allow local data to be extrapolated to an entire site. Numerous methods have been proposed for relating piezocone data to preconsolidation pressure and the overconsolidation ratio, but their validity is still uncertain. In this paper, nine methods are compared on the basis of data collected on 31 sensitive clay sites in Quebec whose preconsolidation pressure profiles are well known. Each method is briefly presented and the most promising are identified. The simplest method, which directly relates preconsolidation pressure to net tip resistance, also appears to be the most effective.Key words: clay, preconsolidation pressure, overconsolidation ratio, piezocone, correlations.Les profils de pression de préconsolidation et du rapport de surconsolidation constituent les éléments les plus importants en ce qui concerne le comportement mécanique des dépôts argileux. Leur évaluation se fait par un nombre limité d'essais de laboratoire, mais les données fournies par le piézocône de manière presque continue peuvent permettre une extrapolation à l'ensemble du site de ces données locales. De nombreuses méthodes ont été proposées pour corréler les données du piézocône et la pression de préconsolidation ou le rapport de surconsolidation mais leur validité est encore incertaine. Dans le présent article, neuf méthodes sont examinées à partir de données provenant de 31 sites d'argile sensible de la province du Québec pour lesquels les profils de pression de préconsolidation sont bien connus. Chaque méthode est brièvement présentée et les méthodes les plus intéressantes sont identifiées. Il semble que la relation entre la pression de préconsolidation et la résistance en pointe nette, qui est la plus simple, est aussi la plus efficace.Mots clés : argile, pression de préconsolidation, rapport de surconsolidation, piézocône, corrélations. [ABSTRACT FROM AUTHOR]

The paper presents the results of laboratory triaxial compression tests to study the stiffness of very loose Fraser River sands. The stiffness has been shown to be very dependent on the time of confinement prior to shearing and the stress ratio at which the sample is aged. Higher stress ratios resulted in very low initial moduli with no ageing, but the moduli increased by several hundred percent during the first 1000 min of ageing. For ageing at a stress ratio of 1.0 (i.e., isotropic ageing), the initial moduli were higher than those for ageing at high stress ratios, but the stiffness increased by only about 60% during the first 1000 min of ageing. The rate of stiffness increase was approximately linear with the logarithm of time up to ageing times of 10 000 min (>1 week). Ageing at any stress ratio resulted in reduced contractive volumetric strain during subsequent shearing, reflecting a change in soil structure during ageing. The dℇ[sub v] /dℇ[sub a] ratio under triaxial compression loading decreased as the ageing stress ratio increased. The results suggest that close attention must be paid to the age of laboratory samples prepared to study the stress–strain response of sands at strains up to about 0.1%, particularly in studies on loose sand.Key words: sands, ageing, creep, modulus.Cet article présente les résultats d'un programme d'essais en laboratoire pour étudier la rigidité de sables très lâches du fleuve Fraser au moyen d'essais de compression triaxiale. On a montré que la rigidité était très dépendante du temps de confinement antérieur au cisaillement et du rapport des contraintes sous lequel l'échantillon a vieilli. Des rapports de contraintes plus élevés ont donné des modules initiaux très faibles sans vieillissement, mais les modules ont augmenté de plusieurs 100 % au cours des mille premières minutes de vieillissement. Sous un vieillissement isotrope, les modules initiaux étaient plus élevés que pour des rapports de contraintes plus élevés mais la rigidité a augmenté de seulement environ 60 % durant les 1000 premières minutes de vieillissement. La vitesse d'augmentation de la rigidité était approximativement linéaire en fonction du logarithme du temps jusqu'à des temps de vieillissement de 10 000 minutes (>1 semaine). Le vieillissement sous n'importe quel rapport de contraintes a donné des déformations volumétriques de contraction réduites durant le cisaillement subséquent, ce qui indiquait un changement dans la structure du sol durant le vieillissement. Le rapport dℇ[sub v] /dℇ[sub a] sous chargement triaxial en compression a diminué lorsque le rapport de contraintes de vieillissement augmentait. Les résultats suggèrent que l'on doit porter un attention particulière à l'âge des échantillons préparés en laboratoire pour étudier la réponse contrainte-déformation des sables jusqu'à des déformations de 0,1 %, particulièrement dans les études sur le sable lâche.Mots clés : sables, vieillissement, fluage, module.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Environmental engineering is one of the most complex and fastest-growing disciplines in engineering. The scope of the field includes issues from public health protection to aesthetics, and from the impact on business development to the development of legislation, standards, regulations, and guidelines, to their enforcement and environmental protection. The issues include contaminants in gases, liquids, and solids and the phase transfers of the contaminants. The sub-specialties of environmental engineering address all these areas including the treatment of water, liquid waste, solid waste, and gaseous materials, protection of the environment through proactive measures, and the development of effective regulations. Environmental engineers have the necessary skills to address these issues and improve the quality of life of humans and other living things in an effective, sustainable, and economical manner. This paper outlines the evolvement of environmental engineering and identifies many of the exciting new directions of environmental engineering profession. Key words: environmental engineering, quality of life, future directions, water, wastewater, air quality, solid wastes, site remediation.Le génie de l’environnement est une des disciplines de l’ingénierie qui est des plus complexe et qui, des génies, croît le plus rapidement. Létendue de ce domaine inclut des sujets qui vont de la protection de la santé publique à l’esthétique, et de l’impact sur le développement d’affaires au développement de législations, normes, règlements et guides et leur mise en vigueur, et à la protection environnementale. Les sujets incluent des contaminants gazeux, liquides et solides, et le transfert de phase des contaminants. Les spécialités du génie de l’environnement abordent tous les domaines incluant le traitement de l’eau, les déchets liquides, les déchets solides et matériaux gazeux, la protection de l’environnement par le biais de mesures pro-actives et le développement de règlements efficaces. Les ingénieurs de l’environnement ont les compétences nécessaires pour aborder ces sujets et améliorer la qualité de vie des êtres humains et autres espèces vivantes d’une façon efficace, durable et économique. Cet article souligne l’évolution du génie de l’environnement et identifie plusieurs des nouvelles directions excitantes de la profession du génie de l’environnement.Mots clés : génie de l’environnement, qualité de vie, directions futures, eau, eau usée, qualité de l’air, déchets solides, réhabilitation de sites.[Traduit par la rédaction] [ABSTRACT FROM AUTHOR]

This paper presents the results of an extensive field investigation of several instrumented road sections in the Province of Quebec, Canada. Falling-weight deflectometer tests, static load tests on embedded plates at different depths, large dynamic cone penetration (DCP) tests, and piezocone tests (CPTU) were performed to study the mechanical response of the pavement. A correlation between elastic deformation modulus inferred from the plate load tests and DCP penetration index was obtained for nine different sites. A correlation between the equivalent elastic modulus of uniform subgrade soils and piezocone tip resistance was also established using data from the falling-weight deflectometer. A procedure for calculating the deflection basin for any pavement system placed over a more complex subgrade stratigraphy was proposed using these correlations. The proposed procedure was validated on two sites and its performance was adequate, since the calculated deflection basins agreed well with the measured deflection basins.Key words: penetration test, piezocone, deflection, pavement, in situ.Cet article présente les résultats d'une étude élaborée sur le terrain de plusieurs sections de route instrumentées dans la Province de Québec, Canada. Des essais au déflectomètre à masse tombante, de chargement statique sur des plaques enfouies à différentes profondeurs, de pénétration dynamique d'un gros cône (DCP), et de piézocône (CPTU) ont été réalisés pour étudier la réponse mécanique de la chaussée. Une corrélation entre le module de déformation élastique déduit des essais de chargement de plaques et l'indice de pénétration DCP a été obtenue pour neuf sites différents. Une corrélation entre le module élastique équivalent des sols de fondations uniformes et la résistance en pointe du piézocône a aussi été établie au moyen des données du déflectomètre à masse tombante. En partant de ces corrélations, on a proposé une procédure pour calculer le bassin de déflexion pour n'importe quel système de chaussée reposant sur une stratigraphie d'infrastructure complexe. La procédure proposée a été validée sur deux sites et sa performance a été adéquate puisque les bassins de déflexion calculés concordaient bien avec les valeurs mesurées.Mots clés : essai de pénétration, piézocône, déflexion, chaussée, in situ.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

This paper reports the results of a laboratory study of the effects of (i) manhole proximity to installation site, (ii) pipe slope (i.e., approach velocity), (iii) upstream head measurement location, and (iv) submergence on the "hydraulics" of two types of sewer weirs used by the City of Ottawa. The City's streamlined form of broad-crested weir and its compound-shaped sharp-crested weir were initially calibrated for a "pipe straight"-arrangement (no upstream manhole is present) for a wide range of flow conditions at 0.2%, 0.4%, and 1.0% pipe slopes. The calibration tests were then repeated with the weirs positioned immediately downstream of a model manhole structure ("manhole"-arrangement). Corresponding data sets were compared to determine the effects of (i) approach velocity and (ii) manhole proximity (for two different shapes of manhole "benching") on the respective weir discharge coefficients.Key words: sewer weirs, broad-crested weir, compound sharp-crested weir, calibration, sewer benching, discharge coefficients.Cet article rapporte les résultats d'une étude en laboratoire sur les effets de : (i) la proximité des bouches d'égout du site d'installation, (ii) la pente des conduites (i.e., vélocité d'approche), (iii) l'emplacement des mesures de la hauteur de la colonne d'eau en amont, et (iv) la submersion sur « l'hydraulique » de deux types de crêtes pour égouts utilisés par la ville d'Ottawa. Les profils d'écoulement des crêtes rectangulaires de la ville et de ses crêtes triangulaires on été calibrés au départ pour un arrangement de « conduites droites » (aucune bouche d'égout présente en amont), pour une variété de conditions d'écoulement ayant des pentes de conduites de 0,2%, 0,4% et 1,0%. Les tests de calibration ont été répétés avec les crêtes positionnées immédiatement en aval d'un modèle d'une structure de bouche d'égout (arrangement « bouche d'égout »). Les banques de données correspondantes ont été comparées afin de déterminer les effets de : (i) la vélocité d'approche, et (ii) la proximité de la bouche d'égout (pour deux types différents de formes de bouche d'égout) sur les coefficients d'écoulement des crêtes respectives.Mots clés : crêtes pour égouts, crête rectangulaire, crête triangulaire, calibration, structure de support pour égouts, coefficients de déversement.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

This paper presents the results of an analytical study on the nonlinear deformation and ductility response of reinforced concrete ductile coupled shear walls (CSWs) under seismic loadings. The CSWs were designed, calculated, and detailed in compliance with the National Building Code of Canada (NBCC) 1995 and the Canadian Concrete Standard CAN3-A23.3-94. The parameters and assumptions of the study as well as the description of the models and the procedure were fully described elsewhere. Results indicated that the maximum interstorey drift from dynamic analyses was well below that obtained from static analyses with NBCC specified lateral forces. It was also found to be substantially lower for tall CSWs compared to short or medium-height walls, and decreased only slightly as the degree of coupling increased within the range considered in this study. It was also highest for seismic records with low PGA/PGV ratios. Plastic hinge rotations as well as accumulated plastic hinge rotations generally decreased as the number of storeys increased. The maximum displacement ductility demand factor remained below the NBCC value of 4.0 specified for ductile CSWs. The influence of degree of coupling on the maximum displacement ductility demand factor was found negligible. Also, the maximum displacement ductility demand factor generally decreased as the number of storeys increased. The maximum rotational ductility demand factor in coupling beams decreased as the number of storeys increased and was generally less than the practical accepted limit of 10, except for a few short CSWs.Key words: coupled shear walls, reinforced concrete, seismic, degree of coupling, frequency content, interstorey drift, plastic hinge deformation, ductility.Cet article présente les résultats d'une étude analytique sur les déformations non-linéaires et la réponse ductile de murs de refend couplés (« coupled shear walls », CSWs) ductiles en béton armé sous des charges sismiques. Les CSWs sont conçus, calculés et détaillés en respectant le Code national du bâtiment du Canada (CNBC) de 1995 et les Normes canadiennes sur le béton CAN3-A23.3-94. Les paramètres et hypothèses de l'étude de même que la description des modèles et de la procédure sont décrits ailleurs de façon détaillée. Les résultats indiquent que le mouvement maximal inter-étages provenant des analyses dynamiques est bien en-deça de celui obtenu à partir des analyses statiques avec les forces latérales spécifiées par le CNBC. Il a aussi été trouvé qu'il est subtantiellement plus bas pour des CSWs élevés comparés à des CSWs délévation moyenne à basse, et décroît légèrement seulement lorsque le degré de couplage s'accroît à l'intérieur de l'intervalle considéré dans cette étude. Il a aussi été le plus grand pour des enregistrements sismiques avec des rapports PGA/PGV bas. Les rotations plastiques à la rotule de même que les rotations plastiques à la rotule accumulées, en général, diminuent lorsque le nombre d'étages augmente. Le facteur de ductilité en déplacement maximal reste sous la valeur de 4,0 specifiée par le CNBC pour des CSWs ductiles. L'influence du degré de couplage sur le facteur de ductilité en déplacement ductile maximale a été trouvé comme étant négligible. Aussi, le facteur de ductilité en déplacement maximal décroît lorsque lorsque le nombre d'étages s'accroît. Le facteur de ductilité rotationnelle maximal dans le couplage des poutres décroît lorsque le nombre d'étages s'accroît, et a été en géneral moindre que la limite pratique acceptée de 10, sauf pour quelques CSWs courts.Mots clés : murs de refend, béton armé, sismique, degrée de couplage, contenu de fréquence, mouvement inter-étages, déformation plastique à la rotule, ductile.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

This paper reviews the flood frequency characteristics of the Red River at Winnipeg. The impacts of persistence in the flood series on estimates of flood quantiles and their associated confidence intervals are examined. This is done by generating a large number of data sequences using a mixed noise model that preserves the short-term and long-term correlation structures of the observed flood series. The results reveal that persistence in the data series can lead to a slight increase in the expected flood magnitude for a given return period. More importantly, persistence is shown to dramatically increase the uncertainty associated with estimated flood quantiles. The 117-year flood series for the Red River at Winnipeg is demonstrated to be equivalent to roughly 45 years of independent data.Key words: flood frequency, extreme events, simulation, historical data.Cet article examine les caractéristiques de la fréquence des crues de la rivière Rouge à Winnipeg. Les impacts de la persistance dans la série de débits sur les estimés des quantiles de crues et leurs intervalles de confiance associés sont examinés. Ceci est effectué en générant un large nombre de séquences de données en utilisant un modèle avec bruits mixtes qui préserve la structure de corrélation à court et à long terme de la série de débits observés. Les résultats révèlent que la persistance dans la série de données peut mener à une légère augmentation de la magnitude anticipée de la crue pour une certaine période de retour. Plus important encore, il a été montré que la persistance augmente dramatiquement l'incertitude associée avec l'estimation des quantiles de crues. La série de 117 ans de débits pour la rivière Rouge à Winnipeg a démontrée être équivalente à 45 ans de données indépendantes.Mots clés : fréquence de crues, événements extrêmes, simulation, données historiques.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

The R.H. Saunders dam is one of over one hundred concrete dams, worldwide, suffering from structural and operational problems due to the expansion of concrete resulting from alkali–aggregate reaction. A laboratory test methodology for measuring the residual expansion rate in these dams with simulation of field environment has been developed. This paper describes the test principles and method of interpretation of the different tests developed. Results of various expansion tests performed on samples recovered from the R.H Saunders dam (Canada) are presented. Results showed that the expansion rates measured in laboratory are consistent with those measured by extensive instrumentation in the field (in situ rebar tests, levelling data, stress meters, and in situ overcoring data). It is believed that the test methodology developed provides the necessary and inexpensive tools for measuring the stress-dependent residual expansion potentials in concrete dams. It would also have an impact on the design of remedial measures and the prediction of future performance because of the reliability and versatility of the test method.Key words: dams, concrete, expansion, alkalis, aggregate, reaction, cement.L'ouvrage de retenue en béton R.H. Saunders, parmis une centaine à travers le monde, souffre de problèmes structuraux et opérationnels liés à l'expansion du béton suite à une réaction alcali–granulat. Une méthodologie basée sur des tests en laboratoire simulant l'environnement du terrain a été développée pour mesurer la vitesse de l'expansion résiduelle dans ces barrages. Cette étude décrit les principes des tests et la méthode afin d'interpréter les différents tests développés. Les résultats des différents tests d'expansion effectués sur des spécimens provenant du barrage R.H. Saunders (Canada) sont présentés. Les résultats ont montrés que les vitesses d'expansion mesurées en laboratoire concordent avec celles mesurées par une vaste instrumentation sur le terrain (test in situ de l'armature, données de nivellement, relevé des contraintes et données in situ de carottages). Il est convenable de croire que la méthodologie développée donne les outils nécessaires et abordables afin de mesurer les potentiels dépendants des contraintes d'expansion résiduelle des barrages en béton. La méthodologie devrait avoir un impact sur la conception de méthodes de réhabilitation et sur les prédictions de performances futures à cause de sa fiabilité et sa polyvalence.Mots clés : barrage, béton, expansion, alcalis, granulat, réaction, ciment.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

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]

To analyze the effects of strain rate and viscoplastic strain on consolidation of natural clay, this paper presents a nonlinear viscoplastic model in which viscoplastic behaviour is modeled by a unique effective stress (σ'[sub v] ) – viscous strain (ℇ[sub v] ) – viscous strain rate (ℇ[sup ·] [sub v] ) relationship. The proposed model can consider the effects of strain rate and viscoplastic strain on consolidation, to take into account the difference in strain rate between laboratory and field conditions, and the combined processes of generation and dissipation of pore pressure during consolidation. This model can also predict the behaviour of clay during stepwise loading, constant rate of strain, and relaxation of effective stress. The predicted values using numerical analysis are compared with measured values in laboratory tests and in situ, under an embankment built on soft clay at Berthierville, Quebec. It is possible to estimate the consolidation behaviour of natural clay with reasonable accuracy using the proposed nonlinear viscoplastic model.Key words: consolidation, soft clay, strain rate, viscoplastic, relaxation.Dans le but d'analyser les effets de la vitesse de déformation et de la déformation viscoplastique sur la consolidation de l'argile naturelle, cet article présente un modèle viscoplastique non linéaire dans lequel le comportement est modélisé par une relation unique contrainte effective-déformation visqueuse-vitesse de déformation visqueuse σ'[sub v] – ℇ[sub v] – ℇ[sup ·] [sub v] . Le modèle proposé peut prendre en considération les effets de la vitesse de déformation et de la déformation viscoplastique sur la consolidation pour tenir compte de la différence dans les vitesses de déformation entre les conditions en laboratoire et sur le chantier, de même que les processus combinés de génération et de dissipation de la pression interstitielle durant la consolidation. Ce modèle peut aussi prédire le comportement de l'argile en incluant le chargement par étape, la vitesse de déformation constante, et la relaxation de la contrainte effective. Les valeurs prédites au moyen de l'analyse numérique sont comparées avec celles mesurées dans les essais en laboratoire et in situ sous un remblai construit sur de l'argile molle à Berthierville, Québec. Il est possible d'estimer le comportement en consolidation de l'argile naturelle avec une précision raisonnable au moyen du modèle viscoplastique non linéaire proposé. Mots clés : consolidation, argile molle, vitesse de déformation, viscoplastique, relaxation.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

New bedrock mapping completed as part of the Nechako NATMAP Project indicates that the area between Babine and Takla lakes in central British Columbia is underlain by rocks of the Early Permian Asitka, Late Triassic Takla, and Early to Middle Jurassic Hazelton volcanic-arc assemblages of the Stikine Terrane. These are cut by large composite stocks of quartz diorite, granodiorite, and quartz monzonite previously mapped as the Late Triassic to Early Jurassic Topley intrusions. New U/Pb (n = 6) and laser [sup 40] Ar/[sup 39] Ar (n = 10) isotopic age dates reported in this paper suggest there are two distinct ages of plutons: the Topley intrusive suite with isotopic ages between 218 and 193 Ma; and, east of Babine Lake, the new Spike Peak intrusive suite with isotopic ages ranging from 179 to 166 Ma. West of the main plutonic belt is a thick volcanic succession of subaerial, porphyritic andesite flows, volcanic breccias, and rhyolitic ash-flow tuffs that have isotopic ages between 185 and 174 Ma. These rocks are assigned to the Saddle Hill Formation of the Hazelton Group. The plutonic roots of this proximal arc assemblage are most likely the coeval and compositionally similar plutons of the Spike Peak intrusive suite that have been unroofed in the area east of the Takla Fault. Major oxide and trace element data support the interpretation that the Topley and Spike Peak granitic rocks formed in a juvenile volcanic-arc environment and that magmatism is related to melts generated above a long-lived subduction zone of unknown orientation.Une nouvelle cartographie effectuée dans le cadre du projet NATMAP Nechako indique que la région entre les lacs Babine et Takla au centre de la Colombie-Britannique est recouverte de roches des assemblages d'arcs volcaniques du terrane de Stikine, soit Asitka du Permien précoce, Takla du Trias tardif et Hazelton du Jurassique précoce à moyen. Ces assemblages sont recoupés par des petits massifs intrusifs composites de diorite quartzique, de granodiorite et de monzonite quartzique qui avaient auparavant été cartographiés en tant que les intrusions Topley, du Trias tardif au Jurassique précoce. De nouvelles datations U-Pb (n = 6) et isotopes laser [sup 40] Ar/[sup 39] Ar (n = 10) présentées dans cet article suggèrent deux âges distincts de plutons, soit la suite intrusive de Topley avec des âges isotopiques entre 218 et 193 Ma et, à l'est du lac Babine, la nouvelle suite intrusive de Spike Peak dont les âges isotopiques varient de 179 à 166 Ma. À l'ouest de la ceinture plutonique principale se trouve une séquence volcanique épaisse d'écoulements subaériens d'andésite porphyrique, des brèches volcanique et des tufs d'écoulement de cendre rhyolitique dont les âges isotopiques varient entre 185 et 174 Ma. Ces roches sont assignées à la Formation de Saddle Hill du Groupe Hazelton. Les racines plutoniques de cet assemblage d'arc proximal sont fort probablement les plutons contemporains et à composition similaire de la suite intrusive de Spike Peak qui ont été décapés dans la région à l'est de la faille de Takla. Les données sur les principaux oxydes et les éléments traces corroborent l'interprétation que les roches granitiques de Topley et de Spike Peak se sont formées dans un environnement d'arc volcanique juvénile et que le magmatisme est relié aux fusions qui se sont produites au-dessus d'une ligne de subduction de longue durée mais dont l'orientation est inconnue.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Environmental engineering education has been an active option for engineers from all disciplines for nearly 50 years at the graduate level. Some graduate programs expanded to integrate students with undergraduate science degrees with the engineering programs, since the cross discipline interaction is required outside the academic programs. In the mid-1980s interest increased to such a level that undergraduate programs began to form. Several of these programs have been accredited in their various forms recognizing the diversity of the field and those presenting the programs. The progression from graduate-degree-based specializations to broad-based undergraduate programs reflects both the increased knowledge in the field and the increased demand for professional engineers capable of responding to public health and environmental protection issues. Graduate programs greatly expand fundamental knowledge of physical, chemical, and biological processes and their application to protection problems. Of course, the doctorate is dedicated to the development of significant new knowledge. This paper defines several of the basic components of the environmental engineering profession and the educational process needed to produce qualified environmental engineers. [ABSTRACT FROM AUTHOR]

We show that the comment of K.M. Aggarwal (2018, Can. J. Phys. 96(10), doi:https://www.nrcresearchpress.com/doi/pdf/10.1139/cjp-2017-0842), although being only marginally relevant to the content of the original paper (2017, Can. J. Phys. 95(2), doi:https://www.nrcresearchpress.com/doi/pdf/10.1139/cjp-2016-0513), misinterprets our results and leads to an incorrect conclusion. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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). [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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). [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In the past few years, artificial neural networks (ANNs) have been used in describing and modelling wastewater treatment processes. Artificial neural network models can be identified without a detailed knowledge of the kinetics of the system to be modelled. Also, ANN models can potentially contain a great deal of information about the system itself, including the same type of information contained in conventional deterministic models. The fact that these models can be continuously updated with minimal resource requirements makes them very attractive for application in a real-time control scenario. In the current paper, applications of ANNs in the field of wastewater treatment performance prediction are reviewed. In addition, this paper presents a case study that reports some comprehensive modelling work to develop nonlinear neural network prediction models for the Gold Bar Wastewater Treatment Plant (GBWWTP), the largest sewage treatment facility in Edmonton, Alberta. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various papers within the issue on permafrost, soil or rock that remains at or below zero degree for 2 or more years in Canada.

The following series of papers comprise a symposium on Dietary Reference Intakes (DRIs), which are the new dietary recommendations for North Americans, that was presented at the 2004 Annual Meeting of the Canadian Society for Exercise Physiology. The process of developing the DRIs has been an enormous undertaking resulting, thus far, in 12 book-length reports spanning from 1997 to 2004. It was therefore timely to review the recommendations, describe the considerations for physical activity that went into setting the recommendations, and, where possible, indicate how the DRIs may be applied to athletes. [ABSTRACT FROM AUTHOR]

The article reports on the 75th Anniversary of the Canadian Journal of Research by the National Research Council (NRC) of Canada. NRC Research Press is Canada's foremost publisher of scientific and technical information. The Press publishes 15 journals in fields as diverse as genomics, chemistry, zoology, and civil engineering. NRC Research Press journals focus on critical, high-quality research from Canadian universities and industry and from international research centers. In 2003 the Press received 3941 research papers from authors in Canada and around the world, of which 1841 were accepted and published after rigorous peer review by international boards of associate editors and peer reviewers.

Introduces a series of articles featured in the special issue of the "Canadian Journal of Earth Sciences." Discussion of articles on the final compendium of papers on the Alberta Basement Transect of Lithoprobe.

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. [ABSTRACT FROM AUTHOR]

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 = 8,892) 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This article presents information about the articles published in the August 1, 2004 issue of the journal "Canadian Journal of Botany." This issue is a collection of invited, peer-reviewed symposium papers from the 4th International Conference on Mycorrhizae held in Montreal, Quebec, in August 2003.

This paper examines the application of the artificial neural network (ANN) modeling technique to model a lime softening process at a full-scale drinking water treatment facility. The modeling was done for the Rossdale Water Treatment Plant (WTP) operated by EPCOR Water Services Inc. in Edmonton, Alberta. It was determined that ANN can model a lime clarifier accurately and with superior performance to other modeling methods. During the development stage, a prediction of alum clarifier pH also becomes necessary, and a very accurate inferential (virtual) sensor for pH was developed using ANN. The ANN models were also integrated with the Supervisory Control and Data Acquisition (SCADA) system of the plant so that real-time predictions of lime doses and effluent total hardness could be monitored. It was shown that the performance of the ANN models that were developed using average daily values for the parameters also work well when they are executed in real time. [ABSTRACT FROM AUTHOR]

Artificial neural network (ANN) technology has evolved from the experimental stage into actual industrial applications. To achieve this significant transition, careful planning and adjustment are required. This paper illustrates such an example in the water treatment industry. The project objective is to upgrade the ANN models from a previous research project and install the system on-line in the Rossdale Water Treatment Plant in Edmonton, Alberta, Canada, to forecast raw water colour one day ahead. The article discusses the important issues and techniques to upgrade the neural network model to the actual application. Furthermore, sufficient communication is also required between the designers and the users to address the applicability and user friendly issues in model implementation. Failure in communication can render the whole process ineffective. Possible improvements are also recommended for the future on-line applications. [ABSTRACT FROM AUTHOR]