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Wood discoloration was investigated in 721 paper birch (Betula papyrifera Marsh.) trees from 146 sites across the managed forest of Quebec, Canada. Discoloration was present at breast height in 85% of trees, but its impact was limited in terms of tree basal area and volume, with proportions of 6.4% and 3.6%, respectively. These two measures were strongly correlated. Discoloration changed wood appearance but had no effect on microfibril angle and modulus of elasticity. Discolored wood was nevertheless denser, probably due to the accumulation of colored extractives. Predictive models were also developed and applied to 415 711 paper birch trees from 51 689 inventory plots across the province to study regional variation. Higher proportions of discolored basal area were obtained in the southwestern areas of the province where the climate is warmer and drier. In these areas, paper birch trees are larger and, likely, support bigger branches which can cause larger columns of discoloration when broken. Lower proportions were found in eastern regions where snowfall is more abundant. Smaller, more flexible branches in trees growing in these areas could explain this result. This study confirms the feasibility of large-scale mapping of wood discoloration in standing trees based on forest inventory and climate data. [ABSTRACT FROM AUTHOR]

RNA interference (RNAi) is a useful tool to assess gene function by knocking down expression of a target gene and has been used successfully in domestic and laboratory organisms. However, the use of RNAi for functional genomics has not fully extended into ecological model organisms in natural environments. Assessment of gene function in the wild is important because gene function can be environmentally and context dependent. Here, we present a case study using RNAi to assess gene function in wild paper wasps Polistes metricus, to test roles for two candidate genes ( NADH dehydrogenase ( NADHdh) and retinoid and fatty acid binding protein ( RfaBp)) in the development of reproductive castes. Previous studies have shown that these genes are upregulated in larvae that become queens compared to workers, but this pattern was reversed in the laboratory, making field-based studies necessary. We orally administered dsRNA to larvae in field colonies and found evidence of a short-term knockdown followed by a compensatory rebound in expression for RfaBp. We also observed the predicted worker-like decrease in lipid stores in NADHdh dsRNA treated wasps, suggesting a possible role for NADHdh in caste development. We discuss our results in the context of challenges for using RNAi for functional genomics in ecological model organisms in the field. [ABSTRACT FROM AUTHOR]

We analyze the total factor productivity (TFP) of the pulp and paper industry in three Canadian provinces (British Columbia, Ontario, and Quebec) and in three United States (US) states that are contiguously located south of the border (Washington, Illinois, and Maine) over the period of 1971 to 2005. We find that the industry in the three Canadian provinces had much higher TFP growth rates in the era following the Free-Trade Agreement (FTA) signed in 1988. In terms of productivity level, this relative TFP surge allowed the industry in Ontario and British Columbia to move ahead of Illinois and Washington, respectively; however, Quebec trailed further Maine, which is the overall leader in the sample. Our results in this particular case reveal that the Canadian pulp and paper industry did not contribute to the overall Canada-US productivity gap. [ABSTRACT FROM AUTHOR]

Procurement for forest companies with pulp and paper mills aims to ensure that a sufficient volume of wood supply enters the production process. Numerous suppliers and contract types are available; however, their selection is a complex decision for procurement managers. In addition, managers typically dedicate a portion of their wood fiber demand to each group of suppliers, which is referred to as a portfolio strategy. Despite the available literature in contract selection, the consideration of contract types and their characteristics have not been addressed for the complex procurement process. In this study, a mixed-integer optimization model is proposed to best select contracts for pulp and paper procurement. The challenge was to plan deliveries in each time period to satisfy the demand of raw material at the mills. The potential of this model is demonstrated with a case study based on characteristics from a forest company in Quebec, Canada. A comparison between traditional fixed and flexible contracts is presented. Different portfolio strategies are also evaluated for groups of suppliers to investigate potential improvements. [ABSTRACT FROM AUTHOR]

A novel, simple, and low-cost spray painting technique has been developed for the fabrication of microfluidic paper-based devices. The devices that we developed utilize aerosol spray paint to build hydrophobic barriers and employ a hole puncher to obtain paper-based patterned layers and paper dots without using any specialized instruments (e.g., without a laser cutter). The entire manufacturing process is extremely simple, inexpensive, and rapid, which means that it can be applied broadly. Furthermore, the application of the device to iron detection was demonstrated. A linear relationship between the colour value and the iron concentration was observed from 0 to 0.02 g/L. The developed microfluidic paper-based device for iron detection exhibited a low detection limit (0.00090 g/L), good selectivity, and acceptable recovery. [ABSTRACT FROM AUTHOR]

There are only limited theoretical results published on the transition properties of the X1Σ+, A1Π, B1Σ+, C1Δ, D1Σ−, E1Δ, a3Π, b3Σ+, and c3Δ states of BeS, and even some of the states have no theoretical and experimental reports on the relevant aspects of these transitions. Therefore, we derived these transition properties in this study. The potential energy curves of X1Σ+, A1Π, B1Σ+, C1Δ, D1Σ−, E1Δ, a3Π, b3Σ+, c3Δ, d3Σ−, and e3Σ− states of the BeS molecule with their Ω states and the transition dipole moments between them were calculated by the complete active space self-consistent field method, followed by the internally contracted multireference configuration interaction method. For the accurate computation of the transition properties, scalar relativistic corrections and core–valence correlation were considered. The radiative lifetimes were approximately 10−6 s for the A1Π and b3Σ+ states, 10−7 s for the E1Δ state, 10−7–10−8 s for the C1Δ and D1Σ− states, and 10−8 s for the B1Σ+, c3Δ, and e3Σ− states. The transition properties of the seven Ω states generated by the X1Σ+, A1Π, B1Σ+, and a3Π electronic states, including several electric dipole-forbidden transitions were researched. In particular, the B1Σ+0+–X1Σ+0+, B1Σ+0+–A1Π1, and A1Π1–X1Σ+0+ systems have strong transitions. In this paper, the radiative lifetimes of A1Π1, B1Σ+0+, a3Π0−, a3Π0+, and a3Π1 electronic states were also computed. For the A1Π1, B1Σ+0+, and a3Π1 states, the distribution of the radiation lifetime with the rotational angular momentum quantum number J at 0 ≤ υ ≤ 15 and J ≤ 70 was evaluated. It is expected that the outcome of the calculations in this paper can contribute some meaningful guidelines for conducting further theoretical and experimental investigations. [ABSTRACT FROM AUTHOR]

This paper presents results of a research project completed to compare the ice-melting capabilities of environmentally friendly alternative deicers with average road salt. Tests were conducted in an environmental chamber where temperatures could be controlled to a certain degree to ensure that the test specimens were in the ideal condition for the most accurate results. There were 168 samples tested and their results were recorded and interpreted throughout this paper. The outcome of this research is based on the amount of brine solution produced during the melting tests, and the depth of ice penetrated for the penetration test. The data showed that all alternative deicers competed evenly or in some cases slightly outperformed rock salt. The results show that there is no clear preference that can be given to the materials; the preference could only be given based on factors not related to ice melting and penetration. [ABSTRACT FROM AUTHOR]

The global emphasis on reducing greenhouse gas emissions means that engineers and architects are increasingly required to account for embodied carbon in their designs. However, there is a lack of knowledge and tools in the structural engineering community to enable calculation of embodied carbon for reinforced concrete structures. This paper aims to address this concern by providing a review of the most up-to-date approaches for calculating embodied carbon as well as the important factors that engineers should consider during the design phase to reduce embodied carbon. Environmental product declarations for concrete in four Canadian provinces will also be compared to illustrate the variability in the embodied carbon and the factors that influence this variability. Finally, the paper will present a case-study on the design of a reinforced concrete beam to demonstrate how to calculate embodied carbon and to illustrate how changes in design can influence the total embodied carbon. [ABSTRACT FROM AUTHOR]

A flexible, lightweight, and high conductivity current collector is the key element that enables fabrication of a high-performance, flexible lithium-ion battery. Here, we report a thin, lightweight, and flexible lithium-ion battery that uses graphite papers deposited with nano-sized metallic layers as the current collector, LiFePO4 and Li4Ti5O12 as the cathode and anode materials, respectively, and a PE membrane soaked in LiPF6 as the separator. Using thin, flexible graphite paper as a substrate for the current collector instead of a rigid, heavy metal foil enables us to demonstrate an ultra-thin lithium-ion battery (total thickness including encapsulation layers of less than 250 μm) that also features a light weight and high flexibility. [ABSTRACT FROM AUTHOR]

Presents a study that examined the role of papermill sludge in the organic forest carbon cycle of paper products. Prediction on the global production of papermill sludge; Impact of paper production and wastepaper recycling trends on the woody carbon components of sludge; Implications of the organic content and carbon content of sludge for dealing with disposal policy and problems.

Translating to the Community (T2C) is a social biorepository designed to advance new diagnostic tools and realign community-clinical processes, with the aim to mitigate the short- and long-term impacts of fetal alcohol spectrum disorder (FASD) as well as prenatal alcohol exposure and its co-morbidities and behaviors. In this paper, we describe the evolution of this repository as a new translational partnership to advance a precision-medicine approach to FASD. Key to its evolution was a partnership between academic researchers, Indigenous communities, families, and a regional diagnostic clinic. We further describe the rationale for social biobanking, the type of banking, ethical engagement of families, communities, and clinics, their roles in repository design, governance, translation, and research activities, types of data collected from families, and how the study data are managed, reported, and accessed. The repository design includes biological samples, social-contextual health-survey data, and clinical data (which are linkable to administrative data) from community and clinical cohorts of diagnosed children, children prenatally exposed but not diagnosed, children suspected to have had a prenatal exposure, and related siblings, biological parents, and unrelated children and their parents. From these cohorts and families, potential studies drawing on this data will shed light on various risk factors, social and biological pathways, and service utilization issues, with the aim to implement primary and secondary prevention and intervention strategies. [ABSTRACT FROM AUTHOR]

Aerated stabilization basins (ASBs) currently account for about one third of the pulp and paper industry's secondary treatment capacity. We surveyed mills with ASBs to analyze design and operating practices. Of the 19 mills that responded, 15 were kraft, reflecting the industry's overall use of ASBs. Biochemical oxygen demand (BOD) and total suspended solids (TSS) loading to the ASBs varied considerably and were factors in biotreatment performance. Problems identified with some ASBs included excessive solids accumulation resulting in the need for frequent dredging, high TSS discharge, and difficulty with nutrient management. Most ASBs have either two or three cells. An important parameter identified for these cells is the benthal settling area. Too small an area results in a higher dredging frequency, with limited nutrient feedback. In general, ASB systems that used the most intensive mixing and aeration in the upstream cells tended to have a smaller benthal settling area, resulting in the need to dredge more frequently. Ideally, some benthal settling should be designed into the upstream cells to allow nutrient feedback where it is needed most. [ABSTRACT FROM AUTHOR]

Red heartwood, a dark nonhomogenous discolouration in paper birch trees ( Marsh.), limits the applications and uses of sawn boards to nonvisible low-value products, thus resulting in substantial value loss. The occurrence and distribution of red heartwood were investigated in 12 paper birch trees grown in the province of Quebec, Canada. The youngest tree was 62 years old at breast height and the oldest 86 years old for an average of 75 years old. In this study, 225 occurrences of external traits, relating to branch scars and forks, previously proposed as initiation points for red heartwood were identified and measured. The distribution of red heartwood was digitally mapped and the effect of these external traits on the red heartwood surface and shape inside each tree was examined. Results show that red heartwood initiates from an external trait and that multiple external traits can contribute to the development of a red heartwood column following the longitudinal axis of the stem. Red heartwood appeared to initiate mainly from external traits at the base of the tree. A modelling exercise indicated that the width of the red heartwood column inside a standing tree can be estimated from branch scar width and height from the ground. Tree vigour could not be linked to the proportion of red heartwood inside standing trees. A three-dimensional analysis of log shape could potentially be used to detect red heartwood presence in a log before processing to optimize the log sawing pattern. [ABSTRACT FROM AUTHOR]

The increased soil cohesion or reinforcement provided by roots varies among plant species and soil types. This study compared the contribution of paper birch (Betula papyrifera Marsh.) and lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) roots to soil shear resistance in two controlled environment experiments. Roots of paper birch and lodgepole pine trees contributed to a significant increase in soil shear resistance, regardless of soil type. At a shear depth of 0.20 to 0.44 m, paper birch contributed greater reinforcement than lodgepole pine. Both birch and pine provided the most root reinforcement in coarse-textured soil and the least reinforcement in medium-textured silt soil. Soil texture, porosity, and shear strength may have affected root branching of the two species, which in turn may have affected root reinforcement. At less than 1 year of age, paper birch trees planted as plugs can substantially increase soil shear strength compared with lodgepole pine in all soil types. [ABSTRACT FROM AUTHOR]

We use a dynamic, global computable general equilibrium (CGE) model to capture the economic impacts of internet adoption, modeled through reduced demand in the newsprint and printing and writing paper (pulp and paper) industries. Global newsprint consumption is estimated to fall dramatically by 2030. We rely on estimates from another study that captures the change in global pulp and paper consumption using the global forest products model (GFPM), based on two scenarios: ( i) full per capita internet adoption by 2100 and ( ii) more rapid full internet adoption by 2050. We incorporate reductions in pulpwood consumption into a global multiregional dynamic CGE model to estimate economy-wide impacts in Canadian provinces, the United States, and the rest of the world. Results indicated that the year 2050 internet adoption scenario would result in a reduction in cumulative discounted gross domestic product (GDP) by as much as 17% in some regions of Canada, reduce GDP by 5.8% in the United States, and increase GDP by 3.3% in the rest of the world from 2006 to 2030. These findings highlight the costs of internet adoption, leaving net benefit analysis of adoption to future work. [ABSTRACT FROM AUTHOR]

This paper investigates the possibilities and challenges of using mass timber as a sustainable alternative for retrofitting existing buildings in Canada. To create the knowledge foundation on which to devise a holistic framework tailored to the specific characteristics of Canada's built environment, a detailed analysis of the types, geographical distribution, structural, and energy features of the local building stock is first presented. Then, previous strategies for enhancing and upgrading existing buildings with engineered timber are reviewed, classified, and evaluated. Finally, to explore economic and environmental implications, a detailed assessment of available life-cycle cost–benefit analysis approaches is conducted alongside their adaptation to Canada's building context. The findings of this paper can inform policymakers, builders, and designers in developing more sustainable building retrofit practices, design, and regulations, in line with Canada's efforts toward net zero emissions. [ABSTRACT FROM AUTHOR]

Effective winter road maintenance relies on precise road friction estimation. Machine learning (ML) models have shown significant promise in this; however, their inherent complexity makes understanding their inner workings challenging. This paper addresses this issue by conducting a comparative analysis of road friction estimation models using four ML methods, including regression tree, random forest, eXtreme Gradient Boosting (XGBoost), and support vector regression (SVR). We then employ the SHapley Additive exPlanations (SHAP) explainable artificial intelligence (AI) to enhance model interpretability. Our analysis on an Alberta dataset reveals that the XGBoost model performs best with an accuracy of 91.39%. The SHAP analysis illustrates the logical relationships between predictor features and friction within all three tree-based models, but it also uncovers inconsistencies within the SVR model, potentially attributed to insufficient feature interactions. Thus, this paper not only showcase the role of explainable AI in improving the ML interpretability of models for road friction estimation, but also provides practical insights that could improve winter road maintenance decisions. [ABSTRACT FROM AUTHOR]

The Global Navigation Satellite System (GNSS) has emerged as a practical and effective technique for studying slow and steady geodynamic movements, enabling continuous monitoring and precise quantification of deformation over different timescales. In Morocco, a network of GNSS stations has been established, offering valuable insights into tectonic processes. This paper focuses on investigating the geodynamic motion of the northwest Moroccan Atlantic Margin. By utilizing GNSS data, subsidence rates and horizontal velocity fields were determined for the first time, providing valuable information for oil and gas exploration activities. The study reveals an active uplift rate of 1 mm/year and a westward horizontal motion of 2.04 mm/year in the Essaouira segment. The paper presents a case study of the Essaouira–Agadir basin (EAB) onshore segment and investigates the anomalous displacement observed in this region compared to other coastal GNSS stations. Possible explanations for the observed movements include local processes such as salt tectonics and regional northwest–southeast compression related to Africa–Eurasia convergence. We suggest that the anomalous movement detected in this work is due to the regional northwest–southeast compression related to Africa–Eurasia convergence imparting an extrusion of the EAB to the west. This research contributes to a better understanding of the geodynamics in the northwest Moroccan Atlantic margin, thereby providing valuable insights for ongoing efforts in oil and gas exploration. Furthermore, it indicates the continued activity of the Agadir fault, which would exhibit a sinistral wrench movement, thus posing a threat to the city of Agadir and its inhabitants. [ABSTRACT FROM AUTHOR]

Five years after spacing a young, 11 m tall paper birch (Betula papyrifera Marsh.) stand, we examine relationships between growth of understory white spruce (Picea glauca (Moench) Voss), subalpine fir (Abies lasiocarpa (Hook.) Nutt.), and level of birch retention. Our objectives were to evaluate the effectiveness of selected measures of competition for estimating the effects of the residual birch and to evaluate the influence of residual birch densities on growth responses of naturally regenerated subalpine fir and white spruce. Basal area of Scouler willow (Salix scouler iana Barratt) and birch were found to effectively predict light transmittance (diffuse noninterceptance). The best models for predicting 4-year volume growth of subalpine fir and white spruce incorporate initial crown volume of the subject trees and transmittance as independent variables. Lorimer's index and Hegyi's index gave similar results to those obtained using basal area and transmittance, suggesting that there is little benefit in including measurements of proximity in a competition index. For both species, the correlation between basal area increment and light was substantially stronger than observed for volume increment. However, height increment of both subalpine fir and spruce was only weakly correlated with measured light levels. The ratio of height increment to volume increment decreased with both increasing initial height and transmittance for subalpine fir and white spruce. [ABSTRACT FROM AUTHOR]

The relationship between the abundance of three functional genes and their corresponding biochemical reaction rates was investigated in several activated sludge and mill effluent microbial communities. Gene probes were prepared for two key denitrification genes (nirS and nirK) and for one nitrogen-fixation gene (nifH) and were validated using a variety of strains of known nir and nif genotype. ATP-based measures of viable cell numbers were used to provide total population sizes. In certain microbial communities (activated sludge enrichment cultures and multiple samples taken from the same mill primary clarifier), a strong correlation was observed between gene abundance and biochemical activity rates. However, when comparing several different nonenriched activated sludge bioreactors and separate primary clarifier microbial communities, the ratio of specific gene abundance to biochemical activity rates varied widely. These results suggest that in cases where a microbial community is not fully induced for a given biochemical activity or when very different communities are compared, quantitative gene probing can give a better measure of a community's potential to carry out the encoded function than can the relevant biochemical assay. However, the gene quantitation method employed here probably underestimated the true number of probed genes present in the microbial communities due to nirS and nifH genes in the communities having reduced DNA sequence similarity with the probes used.Key words: denitrification, nitrogen fixation, quantitative hybridization, activated sludge, primary clarifier.Nous avons examiné les liens existant entre l'abondance de trois gènes fonctionnels et la vitesse des réactions biochimiques correspondantes dans plusieurs communautés microbiennes de boues activées et d'effluents de papetières. Des sondes génétiques furent conçues pour des gènes clés de la dénitrification (nirS et nirK) et pour un gène de la fixation de l'azote (nifH), et furent validées à l'aide d'une panoplie de souches aux génotypes nir et nif connus. Des mesures de nombres de cellules viables se basant sur l'ATP ont été utilisées afin de procurer une estimation des tailles totales des populations. Dans certaines communautés microbiennes (cultures d'enrichissement de boues activées et échantillons multiples recueillis à partir d'un même clarificateur primaire de papetière), une forte corrélation a été observée entre l'abondance des gènes et les taux d'activités métaboliques. Toutefois, le rapport de l'abondance génétique spécifique sur les taux d'activité métabolique ont varié largement lorsque nous avons comparé divers bioréacteurs de boues non enrichies, ainsi que des communautés microbiennes de clarificateurs primaires de papetière distincts. Ces résultats nous indiquent que dans les cas où une activité biochimique n'est pas complètement induite chez une communauté bactérienne ou lorsque des communautés très différentes sont comparées, le sondage génétique quantitatif est d'avantage apte à fournir une mesure du potentiel d'une communauté à accomplir la fonction codée, que l'analyse biochimique pertinente. Cependant, la méthode de quantification des gènes employée ici a probablement sous-estimé le nombre véritable de gènes sondés présents dans la communauté microbienne, puisque les gènes nirS et nifH dans les communautés microbiennes avaient une similitude de séquence inférieure par rapport aux sondes utilisées.Mots clés : dénitrification, fixation de l'azote, hybridation quantitative, boues activées, clarificateur primaire.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

This paper studies substitution between main categories of imported pulp and paper products and between imported and domestic pulp and paper products in the US market. A restricted translog subcost function approach was employed to derive the elasticity of substitution. The results suggest that Canadian pulp and paper products are competitive and have maintained their competitiveness in the US market, and therefore, the challenges faced by the Canadian pulp and paper industry are not because of the loss of its product competitiveness but are due to other reasons such as declining demand for paper products in the United States. It seems that if the Canadian pulp and paper industry wants to retain its dominant position in the world market place, it will have to create global reach and develop new markets. [ABSTRACT FROM AUTHOR]

Freshwater biodiversity is under great threat across the globe as evidenced by more severe declines relative to other types of ecosystems. Some of the main stressors responsible for these concerning trends is habitat fragmentation, degradation, and loss stemming from anthropogenic activities, including energy production, urbanization, agriculture, and resource extraction. Habitat protection and restoration both play an integral role in efforts to save freshwater biodiversity and associated ecosystem services from further decline. In this paper, we summarize the sources of threats associated with habitat fragmentation, degradation, and loss and then outline response options to protect and restore freshwater habitats. Specific response options are to legislate the protection of healthy and productive freshwater ecosystems, prioritize habitats for protection and restoration, enact durable protections, conserve habitat in a coordinated and integrated manner, engage in evidence-based restoration using an adaptive management approach, ensure that potential freshwater habitat alterations are mitigated or off-set, and future-proof protection and restoration actions. Such work should be done through a lens that engages and involves local community members. We identify three broad categories of obstacles that could arise during the implementation of the response options outlined: (a) scientific (e.g., inaccessible data or uncertainties), (b) institutional and management (e.g., capacity issues or differing goals across agencies), and (c) social and political (e.g., prioritizing economic development over conservation initiatives). The protection and restoration of habitats is key to Bend the Curve for freshwater biodiversity, with a comprehensive, connected, and coordinated effort of response options needed to protect intact habitats and restore fragmented, degraded, and lost habitats and the biodiversity and ecosystem services that they support. [ABSTRACT FROM AUTHOR]

To improve the traffic efficiency of bus at a group of intersections and reduce their delay, this paper develops a speed guidance strategy for buses under travel time control at intersection groups. The approach considers the influence of bus departure time, bus station arrival rate, and bus station dwell time. Simulation experiments are carried out on three consecutive intersections along Jinshan Avenue in Fuzhou, China. Results show that the average travel time of buses, the average delay of buses, and the average delay per capita in the priority direction are reduced by 5.5%, 9.9%, and 9.4%, respectively. The optimal rate of the average number of bus stops reached 15.2%. The indicators of the non-priority direction of social vehicles are not significantly affected. It shows that the efficiency of buses has improved after implementing the speed guidance strategy at the intersection groups without affecting the social vehicles as far as possible. [ABSTRACT FROM AUTHOR]

Adhering to ASTM C109/C109M-20 standards ensures quality in cement mortar specimens. However, achieving the required sand gradation per ASTM C778-21 can be challenging. This paper presents a faster method for adjusting sand gradation without compromising ASTM quality standards. The proposed method involves analyzing six silica sand samples of different gradations, pre-screening sands, using Excel Solver for optimal mixture ratios, making automated gradation tweaks with precise calculations, and validating the gradation to ensure ASTM compliance. After making the adjustments, compressive strength tests were conducted on mortars with the modified sands, and the results were compared with those of standard-graded sand. Based on statistical analysis, the new method yielded reliable outcomes with compressive strengths similar to standard sands. This innovation offers a more efficient alternative, paving the way for streamlined practices in civil engineering. [ABSTRACT FROM AUTHOR]

In this paper, the suitability of digital image correlation (DIC) technology in evaluating the flexural behaviour of as-built and carbon-fiber-reinforced polymer (CFRP) strengthened reinforced concrete beams was verified by conducting a four-point bending test on four large-size beams. The DIC data obtained during the tests were compared to the results measured using traditional techniques such as displacement sensors and electrical strain gauges, as well as the findings derived from finite element (FE) numerical simulations. A good agreement was achieved between the local displacement and strain measurements and the data from DIC as a function of the applied load. Moreover, the crack patterns generated by the FE modelling were validated by the corresponding patterns derived from DIC. This suitability study is expected to contribute to the future field implementation of DIC technology to monitor the CFRP-strengthened members of critical structures such as bridges. [ABSTRACT FROM AUTHOR]

Timely road surface condition (RSC) monitoring and maintenance significantly influences road safety. The current RSC relies on fixed road surveillance cameras and in-vehicle cameras. However, the fixed camera demands higher precision, while the in-vehicle camera requires higher timeliness. To address these challenges, this paper introduces an adaptive machine learning framework for simultaneous road surface detection on both device types. Initially, a convolutional neural network-based differentiation module identifies image sources. Subsequently, an adaptive algorithm switching mechanism leads to the development of two algorithms improved upon the real-time object detection algorithms. At last, extensive experiments with datasets collected from Ontario, Canada and Iowa, U.S.A. validate the framework. Results show satisfactory classification accuracy, detection precision, and speed. Notably, the mean average precision, namely mean of the average precision for all categories (mAP), reaches 91.9% for fixed cameras and 90.6% for in-vehicle cameras, outperforming existing road surface snow detection models. [ABSTRACT FROM AUTHOR]

In the framework of Newtonian theory of gravitation, three toy models of a hypothetical gravitational shield (GS) are developed. To satisfy the energy conservation law which is violated in the presence of GS, an existence of a special kind of energy ("G-energy") responsible for shielding and stored in GS is postulated. The models differ from each other by the details of the spatial dependence of the net gravitational acceleration in the presence of GS as well as by the dependence of that acceleration on the amount of G-energy in GS. As an example, the rotation of a dumbbell like object located at the boundary between the regions of space where gravity is affected and not affected by GS is analyzed in details. The motivation to study gravitational shielding, the very existence of which is challenged, is the presence of steadily repeating attempts to observe this phenomenon. No doubt, such attempts will continue in the future. The results obtained in the present paper could be useful in designing such a research. [ABSTRACT FROM AUTHOR]

This report describes the knowledge mobilization and translation outcomes of the Canadian-funded portion of a large, international project called the Food Biomarker Alliance (FoodBAll), which ran from 2015 to 2019. This remarkably successful project led to a large number of important findings, outputs, and impacts. In particular, FoodBAll unequivocally demonstrated that metabolomics could be used to not only discover biomarkers of food intake (BFIs), but also to measure diet in a more objective manner. FoodBAll also created standards for assessing and validating BFIs, papers and databases describing BFIs, and kits for measuring BFIs and it laid the groundwork for many global studies exploring food composition and precision nutrition. [ABSTRACT FROM AUTHOR]

The Miyawaki method, developed by Akira Miyawaki, restores natural forests by planting diverse native species in compact spaces, rapidly creating compact, resilient ecosystems. Initially successful in Japan, its global application bloomed but remains rare in Mediterranean urban areas despite benefits like biodiversity enhancement and climate change mitigation. This method's effectiveness in Mediterranean climates, which face unique challenges like urban heat islands and biodiversity loss, is underexplored in literature and practice. We are leading a project in Italy to identify optimal plant assemblages, addressing the method's documentation gap in urban settings. It explores the potential of Tiny Forests to provide ecosystem services and improve urban liveability against climatic extremes. This note paper details the methodological steps undertaken in this experimental application, offering a tailored approach to test the method's adaptability and impact in Mediterranean urban environments, suggesting a significant opportunity for urban greening and resilience. [ABSTRACT FROM AUTHOR]

This paper evaluates the performance of a new flexible fluid–structure interaction (FSI) module in an open-source computational fluid dynamics (CFD) software—REEF3D—for use in modelling saltmarsh vegetation. Unlike previous studies, which focussed on hydrodynamic response to plants (for example, wave attenuation) to check the accuracy of their numerical modelling efforts, this work attempts to replicate the plants' drag force and motion behaviour, based on results from several physical modelling studies. The flexible FSI module was found to consistently overestimate both the drag and motion of the numerical plants when compared to their physical counterparts. It is hypothesized that this is due to the module's use of linearly elastic material theory for the flexible structures. This is arguably inadequate for the relatively flexible materials of saltmarsh vegetation. [ABSTRACT FROM AUTHOR]

This study aims to develop simple equations for assessing the damage of reinforced concrete (RC) columns subjected to seismic loading. A fiber element model in OpenSees, validated against experimental data, was used to generate a large dataset of 56 548 data values for various RC columns. The Monte Carlo Hierarchical Adaptive Random Partitioning strategy was then applied to evaluate the sufficiency of the dataset and propose reliable equations for estimating the residual displacement ratio, damage index, and residual curvature of RC columns under given displacement demands. A relationship between these parameters and the structural performance levels was also established. Residual displacement is a practical measure that can be observed in the field after an earthquake. The proposed equations facilitate the determination of the performance level of the structure after an earthquake event. The findings of this paper can also be used in designing new structures within a performance-based seismic design context. [ABSTRACT FROM AUTHOR]

The Kashechewan First Nation (KFN) community is located on a floodplain of the north branch of the Albany River, on the west coast of James Bay. Each spring, the community faces the uncertain prospect of evacuation due to ice-jam flooding, the most severe of which occurred in 2006. A study was conducted to develop long-term options for reducing the flood risk to the community, which included dams, dykes, pier and weir type ice-control structures, and conveyance channels. This paper presents a numerical model study on the Albany River in Ontario, Canada to develop ice control as a potential means for mitigating ice-jam flooding at the KFN community using the two-dimensional ice dynamics model DynaRICE. A method was developed to simulate pier type ice-control structures within the model such that the physical channel conditions, flow conditions, and combinations of ice control could be evaluated. The model allowed detailed simulation of ice retention, resulting inundation, and the forces on the individual piers. To optimize the design of the piers, including pier spacing, height, and size, various combinations of ice, flow, and pier conditions were simulated. Numerical modeling facilitated a comparative examination of flood risk reduction to the community from the various ice control options. [ABSTRACT FROM AUTHOR]

The seismic demands of the Reinforced Concrete Shear Walls (RCSWs) system are determined based on Canada's National Building Code (NBC). NBC 2020 features the revised Canadian Seismic Hazard Model and presents the possibility of enhancing demand's accuracy by determining design spectra based on the specific average shear wave velocity, instead of specified site classes. This paper investigates the changes in design demands for RCSWs compared to the previous edition. To do so, fifty-five RCSW prototypes were modelled using distributed mass and stiffness procedure, and their dynamic response was assessed through Modal Response Spectrum Analysis at five locations across Canada. The results highlight significant changes in deformation and force demands, where the majority of cases experienced an increase in 2020 compared to 2015 when demands were determined based on specified site classes. This study also evaluates the log-log interpolation method recommended by NBC 2020 for the design spectral acceleration. [ABSTRACT FROM AUTHOR]

In this paper, we revisit the Stark effect of the hydrogen atom induced by a uniform static electric field. In particular, a general formula for the integral of associated Laguerre polynomials was derived by applying the method for Hermite polynomials of degree n proposed in the work (Anh-Tai T.D. et al., 2021 AIP Advances 11 085310). The quadratic Stark effect is obtained by applying this formula and the time-independent non-degenerate perturbation theory to hydrogen. Using the Siegert state method, numerical calculations are performed and serve as data for benchmarking. The comparisons are then illustrated for the ground and some highly excited states to provide an insightful look at the applicable limit and precision of the quadratic Stark effect formula for other atoms with comparable properties. [ABSTRACT FROM AUTHOR]

Cardiovascular disease (CVD) is the leading cause of death in women. After menopause, sex-specific and gender-specific factors may play an important role in increasing CVD risk, with changes in sex hormones, body fat distribution, lipid and metabolic profile, and structural and functional vascular modifications. Premature and early-onset menopause are detrimental to cardiovascular health due to the early cessation of the protective effect of endogenous estrogen. An independent association of menopause with an increased risk of CVD has been documented in early menopause (<45 years). Sex-related differences are relevant in pharmacokinetics and pharmacodynamics; different enzyme formations, drug compatibility, efficacy, and side effects vary for different sexes. Despite some progress in sex and gender research in CVD, disparities remain. Menopausal hormone therapy (MHT) is available at mid-life for symptoms of menopause and may impact cardiovascular risk. Taken early, MHT may reduce CVD morbimortality. However, this is balanced against the risk of increased thrombosis. This paper reviews physiologic changes that contribute to cardiovascular risk in postmenopausal women and discusses clinical implications. Specifically, it explores the atheroprotective effects of estrogen and MHT and the associations between menopause with lipid levels, hypertension, body composition, and diabetes for women at mid-life and beyond. [ABSTRACT FROM AUTHOR]

Introductory chemistry courses at the undergraduate level offer students a foundation in chemistry principles and an opportunity to develop problem-solving skills. These principles and skill sets are widely applicable across disciplines, and thus first year chemistry courses are a gateway for many programs in science, technology, engineering, and mathematics (STEM). While first-year chemistry courses are essential for STEM students, the resulting large-enrollment classes in universities can lead to challenges in implementing active learning and in helping students to reach the course learning outcomes. The evolving field of chemistry education research (CER) offers data and insight for improving teaching and learning strategies at the undergraduate level. We propose and evaluate an electrochemistry team-based problem-solving module as an active learning component of a large, first-year, blended chemistry course. In this paper, we explore the process for developing the module and evaluate this learning approach through focus groups, a large class survey, and student experience interviews. Through a preliminary case study approach, our findings suggest the interactive module is useful for enhancing conceptual understanding and problem-solving in chemistry, and improving academic confidence in electrochemistry learning outcomes. Moreover, students valued their engagement with the team-based problem-solving modules as an opportunity to build community, learn collaboratively, and successfully approach relevant problems. [ABSTRACT FROM AUTHOR]

The need to transition from traditional single-species fisheries management approaches towards ecosystem-based fisheries management (EBFM), or an ecosystem approach to fisheries, is widely recognised. EBFM is particularly important when considering management actions for economically valuable fisheries for small pelagic forage fish, given their key ecological role. Management strategy evaluation (MSE) is an effective approach to advance the quantitative implementation of EBFM by enabling stakeholders to explore trade-offs among competing ecosystem-related objectives. This paper puts forward six different approaches to advance EBFM with MSE explicity, by taking advantage of data and research already available and by guiding future research. These approaches can be grouped into those which (i) involve the operating model and/or link directly to the operating model while potentially providing additional performance metrics to evaluate ecosystem objectives, (ii) can be incorporated into the performance metrics, and (iii) involve the harvest control rule of the management procedure. This review demonstrates that immediate steps can be taken to implement EBFM targeted at quantitative tactical management, even without a complex, data-rich ecosystem operating model. [ABSTRACT FROM AUTHOR]

Remnant populations of Betula papyrifera Marshall have persisted in the Great Plains after the Wisconsin Glaciation along the Niobrara River Valley, Nebraska. Population health has declined in recent years, which has been hypothesized to be due to climate change. We used dendrochronological techniques to assess the response of B.papyrifera to microclimate (1950–2014) and the normalized difference vegetation index (NDVI) derived from satellite imagery (Landsat 5 TM (1985–2011) and MODIS (2000–2014)) as a proxy for population health. Growing-season streamflow and precipitation were positively correlated with raw and standardized tree-ring widths and basal area increment increase. Increasing winter and spring temperatures were unfavorable for tree growth, while increasing summer temperatures were favorable in the absence of drought. The strongest predictor for standardized tree rings was the Palmer Drought Severity Index, suggesting that B.papyrifera is highly responsive to a combination of temperature and water availability. The NDVI from the vegetation community was positively correlated with standardized tree-ring growth, indicating the potential of these techniques to be used as a proxy for ex situ monitoring of B.papyrifera. These results aid in forecasting the dynamics of the species in the face of climate variability and change in both remnant populations and across its current distribution in northern latitudes of North America. [ABSTRACT FROM AUTHOR]

Facility management maintains building service quality through cycles of condition assessments and rehabilitation. Building components, however, differ in their nature, service lives, deterioration patterns, and textual/visual inspection data. This complicates the condition assessment process and subsequent rehabilitation decisions. This paper proposes a smart condition assessment framework that uses different artificial intelligence (AI) techniques that suit the condition data analysis of different building components. The framework has been applied to a dataset of over 2000 maintenance requests for roof and heating, ventilation, and air conditioning (HVAC) systems across a 600-villa portfolio. To address their varying needs, convolutional neural networks were used on images of roof defects, while enhanced data mining was used on textual data of HVAC systems. Accordingly, work packages of deteriorated components were identified, and a 60-day schedule was developed to repair 203 HVAC units. This research shows how AI can assist facility management with respect to condition assessment, rehabilitation planning, and resource allocation. [ABSTRACT FROM AUTHOR]

Moisture-induced damage has been known as a major premature distresses in asphalt pavement. Numerous review papers have been made to provide the progression in study on moisture damage of asphalt pavement. However, mechanical properties of asphalt mixtures used as a parameter for moisture susceptibility evaluation were not reviewed in detail. To make the review of moisture-induced damage in asphalt pavement more comprehensive, this paper reviews research studies on moisture damage of asphalt pavement in view of mechanical properties as a parameter during the past 50 years. These parameters include tensile strength ratio (TSR), cohesion ratio (CR), dynamic modulus ratio (DMR), resilient modulus ratio (RMR), and shear strength ratio (SSR). TSR and CR are only relevant at bottom of asphalt concrete (AC), while SSR can be used to describe moisture damage at different AC depths. DMR and RMR are concentrated on the impact of moisture damage via performance characteristics of asphalt mixtures. [ABSTRACT FROM AUTHOR]

The road agencies collect and submit weigh-in-motion (WIM) data to the Federal Highway Administration as part of their traffic monitoring program. Therefore, the WIM data should be precise and accurate. One way to evaluate WIM measurement errors is by using the test truck data collected immediately before and after equipment calibration. The limitation of this approach is that the data represent a snapshot in time and may not represent a long-term WIM site performance. This paper presents an approach for estimating WIM system accuracy based on axle load spectra attributes (normalized axle load spectra (NALS) shape factors). This alternative approach allows for characterizing temporal changes in WIM data consistency. The WIM error data collected before and after calibration were related to Class 9 NALS shape factors in the proposed methodology. This paper aims to determine WIM system errors based on axle loading without physically performing WIM equipment performance validation using test trucks. The presented methodology can be used to estimate systematic errors (drift) in the WIM system at any point in time after the equipment calibration. This approach can help highway agencies select optimum timings for routine maintenance and calibration of WIM equipment without compromising its accuracy. The results show that the WIM accuracy for the single axle (SA) and tandem axle (TA) can be estimated with SA and TA NALS shape factors with an acceptable degree of error for bending plate to quartz piezo sensors. Examples are included to demonstrate the application and significance of the developed models. [ABSTRACT FROM AUTHOR]

Bridge infrastructure assets should be planned, designed, constructed, and operated to account for the physical processes that may occur over their service lives. In ice-affected rivers, this includes the interaction of bridge infrastructure with river ice. Advancements in river-ice science and modelling of ice processes in ice-covered rivers have enhanced the abilities of civil/hydrotechnical engineers to plan, design, and construct bridges in and along rivers with seasonal ice covers. In this paper, an overview is presented of ice-related considerations with respect to bridges. The bottom-chord elevation of the bridge superstructure with respect to water and ice levels, pier design to withstand ice forces, the waterway opening for ice passage, ice-induced scour, and research needs are discussed. However, as outlined in the paper, research on ice loads and passage at bridge sites and on hydroclimatic and ice conditions that led to bridge damage and failure remains needed. [ABSTRACT FROM AUTHOR]

Alkalophilic Cellulosimicrobium cellulans CKMX1 isolated from mushroom compost is an actinomycete that produces industrially important and environmentally safer thermostable cellulase-free xylanase, which is used in the pulp and paper industry as an alternative to the use of toxic chlorinated compounds. Strain CKMX1 was previously characterized by metabolic fingerprinting, whole-cell fatty acids methyl ester analysis, and 16S rDNA and was found to be C. cellulans CKMX1. Crude enzyme (1027.65 U/g DBP) produced by C. cellulans CKMX1, having pH and temperature optima of 8.0 and 60 °C, respectively, in solid state fermentation of apple pomace, was used in the production of bleached wheat straw pulp. Pretreatment with xylanase at a dose of 5 U/g after pulping decreased pulp kappa points by 1.4 as compared with the control. Prebleaching with a xylanase dose of 5 U/g pulp reduced the chlorine charge by 12.5%, increased the final brightness points by approximately 1.42% ISO, and improved the pulp strength properties. Xylanase could be substituted for alkali extraction in C–Ep–D sequence and used for treating chemically bleached pulp, resulting in bleached pulp with higher strength properties. Modification of bleached pulp with 5 U of enzyme/g increased pulp whiteness and breaking length by 1.03% and 60 m, respectively; decreased tear factor of pulp by 7.29%; increased bulk weight by 3.99%, as compared with the original pulp. Reducing sugars and UV-absorbing lignin-derived compound values were considerably higher in xylanase-treated samples. Cellulosimicrobium cellulans CKMX1 has a potential application in the pulp and paper industries. [ABSTRACT FROM AUTHOR]

Eucalyptus globulus subsp. globulus Labill. (Tasmanian Blue Gum), native to southeast Australia, is a benchmark species for the pulp and paper industry. We genotyped 397 trees from 16 populations of E. globulus representing the native diversity in Australia using 24 microsatellite loci. Eight genetically distinct groups were detected, consistent with genetic groupings detected in previous quantitative and molecular studies. A sample of 29 Portuguese individuals was added to help clarify the origin of the Portuguese landrace. The results suggest a southern and eastern Tasmania origin for the Portuguese landrace. This genetic framework will enable researchers to investigate the provenance of individuals of unknown pedigree and assess the levels of representation of E. globulus natural variation in the Portuguese landrace. [ABSTRACT FROM AUTHOR]

In the pulp and paper industry, during the manufacturing process, the agglomeration of pitch particles (composed of triglycerides, fatty acids, and esters) leads to the formation of black pitch deposits in the pulp and on machinery, which impacts on the process and pulp quality. Traditional methods of pitch prevention and treatment are no longer feasible due to environmental impact and cost. Consequently, there is a need for more efficient and environmentally friendly approaches. The application of lipolytic enzymes, such as lipases and esterases, could be the sustainable solution to this problem. Therefore, an understanding of their structure, mechanism, and sources are essential. In this report, we review the microbial sources for the different groups of lipolytic enzymes, the differences between lipases and esterases, and their potential applications in the pulping industry. [ABSTRACT FROM AUTHOR]

Presents a study that aimed to determine the levels at which phytosterols are present in Canadian pulp and paper mill effluents (PPME). Description of PPME; Chemicals that form the major fraction of plant sterols in PPME; Processes responsible for the observed removal of plant sterols across the biological wastewater treatment systems.

Objective: To evaluate the toxicity of extracts from disposable chopsticks, toothpicks, and paper cups on L-929 cells. Methods: We followed national standards to prepare the extracts from disposable chopsticks, toothpicks, and paper cups used for the cell culture media, and the morphology of L-929 cells was observed with an optical microscope. The loss rate for adherent cells was evaluated with the trypan blue exclusion method, and cell proliferation was determined using the WST-1 assay. Results: Compared with the control group, the cells cultured in media containing the extracts showed signs of apoptosis and necrosis after culturing for 4 or 7 days, and the loss rate for adherent cells was significantly increased ( P < 0.05). An obvious decrease in cell viability was also observed ( P < 0.05). Conclusion: The extracts from disposable chopsticks, toothpicks, and paper cups can affect the growth and proliferation of L-929 cells and are potentially toxic to humans. [ABSTRACT FROM AUTHOR]

We examined the microbial community structure and quantified the levels of the filamentous bulking organism Thiothrix eikelboomii in samples of activated sludge mixed liquor suspended solids (MLSS) from Canadian pulp and paper mills. Libraries of chaperonin 60 (cpn60) gene sequences were prepared from MLSS total microbial community DNA and each was compared with cpnDB, a reference database of cpn60 sequences (http://cpndb.cbr.nrc.ca) for assignment of taxonomic identities. Sequences similar to but distinct from the type strain of T. eikelboomii AP3 (ATCC 49788T) (~89% identity over 555 bp) were recovered at high frequency from a mill sample that was experiencing bulking problems at the time of sample collection, which corresponded to microscopic observations using fluorescent in situ hybridization with commercially available 16S rDNA-based probes. We enumerated this strain in five mill-derived MLSS samples using real-time quantitative PCR (qPCR) and found that two samples had high levels of the bulking strain (>1012 genomes/g MLSS) and two contained lower but detectable levels of this organism. None of the mill samples contained cpn60 sequences that were identical to the type strain of T. eikelboomii. This technique shows promise for monitoring pulp and paper mill wastewater treatment systems by detecting and enumerating this strain of T. eikelboomii, which may be specific to pulp and paper mill wastewater treatment systems. [ABSTRACT FROM AUTHOR]

During the process of papermaking by pulp and paper plants, a thick and viscous deposits, termed slime, is quickly formed around the paper machines, which can affect the papermaking process. In this study, we explored the composition of the bacterial biota in slime that developed on shower pipes from 2 machines at a Canadian paper mill. Firstly, the composition was assessed for 12 months by DNA profiling with polymerase chain reaction coupled with denaturing gradient gel electrophoresis. Except for short periods (2-3 months), clustered analyses showed that the bacterial composition of the slime varied substantially over the year, with less than 50% similarity between the denaturing gradient gel electrophoresis profiles. Secondly, the screening of 16S rRNA gene libraries derived from 2 slime samples showed that the most abundant bacteria were related to 6 lineages, including Chloroflexi, candidate division OP10, Clostridiales, Bacillales, Burkholderiales, and the genus Deinococcus. Finally, the proportion of 8 bacterial lineages, such as Deinococcus sp., Meiothermus sp., and Chloroflexi, was determined by the Catalyzed Reporter Deposition - Fluorescence In Situ Hybridization in 2 slime samples. The results showed a high proportion of Chloroflexi, Tepidimonas spp., and Schlegelella spp. in the slime samples. Lors du processus de fabrication industrielle du papier, un dépôt épais et visqueux se forme rapidement autour des machines à papier, ce qui peut affecter le processus de fabrication. Dans cette étude, nous avons exploré la composition bactérien ne du dépôt qui s'est développée sur des tuyaux des douches de 2 machines d'une usine à papier au Canada. La composition a d'abord été évaluée pendant 12 mois par la détermination du profil d'ADN par une réaction en chaîne par polymérase couplée à une électrophorèse sur gel en gradient dénaturant. À part de courtes périodes (2-3 mois), les analyses ont montré que la composition bactérienne du dépôt variait substantiellement au cours de l'année, avec moins de 50 % de similarité entre les profils en l'électrophorèse sur gel en gradient dénaturant. Deuxièmement, le criblage de banques géniques d'ARN ribosomique 16S dérivées de 2 échantillons de dépôt a ensuite montré que les bactéries les plus abondantes étaient apparentées à 6 lignées, notamment les Chloroflexi, la division candidate OP10, les Clostridiales, les Bacillales, les Burkholderiales, et le genre Deinococcus. Finalement, la proportion de 8 lignées bactériens comme Deinococcus sp., Meiothermus sp. et Chloroflexi a été déterminée par « Catalyzed Reporter Deposition - Fluorescence In Situ Hybridization » dans 2 échantillons de dépôt. Les résultats ont montré une forte proportion de Chloroflexi, Tepidimonas spp. et Schlegelella spp. dans les échantillons. [ABSTRACT FROM AUTHOR]

Normal paper birch (Betula papyrifera Marsh.) wood has a clear and uniform color. However, some paper birch trees contain reddish-brown-, discolored wood known as red heartwood. Its occurrence, proportion, and vertical distribution were investigated. One hundred and fifty trees were randomly sampled from three stands located at the Montmorency Forest, 75 km north of Quebec City, Quebec, Canada. A subsample of 18 trees showing occurrence of red heartwood at stump height were felled, and 5 cm thick disks were cut at every 0.5 m of height. Red heartwood volume, proportion, and vertical distribution were determined from the disks. Trees with larger diameter at breast height and lower tree height had a higher probability of red heartwood occurrence. Red heartwood starts occurring in 40-year-old trees on average in the stands studied. The volume of red heartwood was positively correlated with tree age, and the proportion of red heartwood was positively related to tree age, and negatively related to the amount of sunlight on the live crown. Red heartwood proportion was 13.3% of the tree merchantable volume, mostly located under the live crown. Le bois de bouleau à papier (Betula papyrifera Marsh.) est normalement clair et uniforme. Toutefois, le bois de couleur brun-rougeâtre présent chez certains bouleaux est appelé cœur rouge. Sa présence, sa proportion et sa distribution verticale dans l’arbre ont été étudiées. Cent cinquante arbres furent sélectionnés aléatoirement dans trois peuplements de la Forêt Montmorency à 75 km au nord de la ville de Québec, Québec, Canada. Un sous-échantillon de 18 arbres présentant du cœur rouge à hauteur de souche ont été abattus et découpés en disques de 5 cm d’épaisseur à tous les 5 m afin de mesurer le volume, la proportion et la distribution verticale du cœur rouge. La probabilité de présence de cœur rouge était plus élevée chez les arbres petits et de fort diamètre. Le cœur rouge était présent dans les arbres de 40 ans et plus en moyenne dans les peuplements étudiés. Le volume de cœur rouge était corrélé positivement avec l’âge de l’arbre. Sa proportion était corrélée positivement avec l’âge de l’arbre et négativement avec la quantité de lumière atteignant la cime vivante. La proportion moyenne de cœur rouge était 13,3 % du volume marchand de l’arbre et il était principalement situé sous la cime vivante. [ABSTRACT FROM AUTHOR]