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This study investigated the use of recycled glass aggregate (RG) as unbound base/subbase material. The experimental tests included compaction, Los Angeles, Micro-Deval, and California bearing ratio (CBR) tests. In this regard, a fine proportion of course limestone aggregate (MG20) was replaced by RG with size ranging from 0 to 5 mm based on the volumetric method. Adding RG to the coarse aggregate improved durability in wet conditions, which is more representative of the field condition of Canada/Quebec, but decreased in dry conditions. CBR values decreased with increasing RG inclusion, but all blends with 0%–100% RG in the fine fraction of MG20 met minimum requirements for unbound granular layers in Quebec. A simple model predicting the resilient modulus values of these materials based on CBR values at different stress levels was suggested. This equation estimates Mr values of various aggregate-RG blends under a wide range of mean stresses based on their CBR values. [ABSTRACT FROM AUTHOR]

Current exterior wall assembly designs for new low-rise residential buildings targeting low-energy demand in heating dominated countries include split-insulation wall and thick-wall assembly designs. Both have been shown to result in thermal efficiency gains compared to building-code minimum assemblies, however long-term hygrothermal performance can vary depending on boundary conditions and the presence of construction deficiencies. Future climate scenarios estimate many heating-dominated climates will experience a reduction in heating-degree day hours and an increase in annual rainfall. Using validated assembly performance data from a Passive House certified facility, a sensitivity analysis is performed to determine the impact of rainwater wetting, air exfiltration and insulation material properties on the hygrothermal response of a thick-wall assembly. Results show that rainwater leakage values of 0.50% and greater of the adhering rainfall on the exterior surface of the assembly results in the greatest risk for failure. The hygrothermal response of the assembly is then examined under a global temperature rise scenario of 3.5°C for five geographic locations across Canada. Results show that an increase in average annual total rainfall does not directly result in an increase in the failure rate of the assembly when a rainwater leak is present. Additional climatic factors, including outdoor air temperature, driving rain and solar radiation received will influence the hygrothermal response of the assembly and need to be considered when modelling the performance under future climate change scenarios. [ABSTRACT FROM AUTHOR]

The assessment of infrastructure conditions is at present a topic of great interest and importance, as well as great challenge. This paper presents a case study of the Samuel De Champlain Bridge (Montreal, QB, Canada), an outstanding stay cable bridge equipped with a comprehensive monitoring system (SHM). Among other SHM features, particular attention was paid to implementation of a strategic corrosion monitoring system. This paper intends to describe the concept design, implementation and data interpretation. Here corrosion sensors have been embedded during construction stage to monitor long term evolution of key electro‐chemical parameters for controlling deterioration of materials. Furthermore, these sensors measure stray current interference generated from the rail system that can cause corrosion. In both cases, abnormal values would warn the owner of the associated increased risk of corrosion. This gives them the possibility to take corrective measures to protect the structure before corrosion becomes a serious threat. [ABSTRACT FROM AUTHOR]

The decision of premature culling cows directly impacts the profitability of dairy farms. A comprehensive characterization of the primary causes of culling reasons would greatly improve both management and selection objectives in dairy cattle breeding programs. Therefore, this study aimed to analyze the temporal frequencies of 34 culling reasons in Canadian Holstein cows. After data editing and quality control, records from 3,096,872 cows culled from 9,683 herds spread across Canada were used for the analyses covering the periods from 1996 to 2020. Reproductive issues were the main culling reason accounting for 23.02%, followed by milk production (20.82%), health (20.39%), conformation problems (13.69%), economic factors (13.10%), accidents (5.67%), age-related causes (1.67%), and workability (1.63%). Nearly fifty-eight percent of cows were culled after 47 months of age. The observed frequencies of culling due to economic factors were lower than expected from 1996 to 2014 and higher than expected between 2015 and 2020. Reproduction issues had the highest culling frequencies during fall (24.54%), winter (24.02%), and spring (22.51%), while health issues were the most frequent (22.51%) culling reason in the summer season. Health issues (25.50%) and milk production (27.71%) were the most frequent culling reasons in the provinces of Quebec and Ontario, respectively. Reproductive issues showed the highest frequency across climates based on the Köppen climate classification, except for Csb (Dry-summer subtropical or Mediterranean climate) and Bsk (Middle latitude steppe climate), which correspond to small regions in Canada, where production was the most frequent culling reason (29.42% and 21.56%, respectively). Reproductive and milk performance issues were the two main culling reasons in most ecozones, except in Boreal Shield and Atlantic Marine, where health issues had the highest frequencies (25.12 and 23.75%, respectively). These results will contribute to improving management practices and selective decisions to reduce involuntary culling of Holstein cows. [ABSTRACT FROM AUTHOR]

In this work, a statistical fuel cell chemo-mechanical membrane degradation model is developed based on the ionomer fibrillar morphology as a framework for use-level membrane durability prediction for fuel cell electric vehicles. The mechanical and chemical degradation modes are separately calibrated with pressure differential-accelerated mechanical stress tests and accelerated membrane durability tests, respectively. Finite element simulations are used to estimate the initial stress distribution across the membrane, while the genetic algorithm with the least squares method is employed to calibrate the model parameters with experimental results, thus reaching a good agreement. Next, the validated model is utilized for a case study of fuel cell electric transit bus operation in the city of Victoria, B.C., Canada. The initial cell voltage profile is obtained using a dynamic fuel cell power system model applied to the transit bus drive cycle recorded during real-world operation. According to the model predictions, reducing the stack nominal power from 396 to 132 kW results in a 148% membrane lifetime enhancement, whereas decreasing the cell temperature from 90 to 70°C results in an 11-fold increase in the membrane lifetime under simulated transit bus operation, thereby exceeding the 25,000-h lifetime target for this application. [Display omitted] • A statistical ionomer morphology based membrane degradation model is developed. • The model is applied to simulate membrane durability for a fuel cell transit bus. • Low stack temperature reduces degradation rates, enhancing membrane lifetime. • Smaller fuel cell stacks can improve membrane durability by reducing potentials. [ABSTRACT FROM AUTHOR]

Background: There is an ever-growing number of patients requiring aortic valve replacement (AVR). Limited data is available on the long-term outcomes and structural integrity of bioprosthetic valves in younger patients undergoing surgical AVR.Methods: The INSPIRIS RESILIA Durability Registry (INDURE) is a prospective, open-label, multicentre, international registry with a follow-up of 5 years to assess clinical outcomes of patients younger than 60 years who undergo surgical AVR using the INSPIRIS RESILIA aortic valve. INDURE will be conducted across 20-22 sites in Europe and Canada and intends to enrol minimum of 400 patients. Patients will be included if they are scheduled to undergo AVR with or without concomitant root replacement and/or coronary bypass surgery. The primary objectives are to 1) determine VARC-2 defined time-related valve safety at one-year (depicted as freedom from events) and 2) determine freedom from stage 3 structural valve degeneration (SVD) presenting as morphological abnormalities and severe haemodynamic valve degeneration at 5 years. Secondary objectives include the assessment of the haemodynamic performance of the valve, all stages of SVD, potential valve-in-valve procedures, clinical outcomes (in terms of New York Heart Association [NYHA] function class and freedom from valve-related rehospitalisation) and change in patient quality-of-life.Discussion: INDURE is a prospective, multicentre registry in Europe and Canada, which will provide much needed data on the long-term performance of bioprosthetic valves in general and the INSPIRIS RESILIA valve in particular. The data may help to gather a deeper understanding of the longevity of bioprosthetic valves and may expand the use of bioprosthetic valves in patients under the age of 60 years.Trial Registration: ClinicalTrials.gov identifier: NCT03666741 (registration received September, 12th, 2018). [ABSTRACT FROM AUTHOR]

• Wood ash can be a potential substitute for coal fly ash. • Partially burnt wood fly ash was characterized. • Wood fly ash negatively affected the mechanical properties of mortar and concrete. • Concrete with 15% wood fly ash as cement replacement showed promising result. The global shutdown of coal industries has led to a shortage of coal fly ash, a commonly used cement replacement. Wood fly ash (WFA), a byproduct abundant in Canada's timber-based construction industry, emerges as a potential alternative. This study comprehensively characterized a locally available partially-burnt WFA to assess its potential to be incorporated into mortar and concrete. The study was divided into three phases: characterization of the WFA, properties of WFA-based mortar, and concrete. Preliminary findings indicate WFA's similarity to class C fly ash. While WFA adversely impacted mechanical properties, at 15% replacement, mortar and concrete performed similarly to the reference mixtures. The compressive strength of mortar and concrete reduced by 6 and 21%, respectively, slump reduced by 6.7% and chloride resistance in fact improved by 19% at 15% WFA replacement. Considering these results, WFA-based concrete presents a viable option for low-carbon construction. [ABSTRACT FROM AUTHOR]

The New Champlain Bridge is a highprofile infrastructure project in North America due to its critical economic importance, the premature deterioration of the existing structure and its visibility throughout the metropolitan area. As the gateway into Montreal, significant architectural input is encapsulated in the project design criteria. Durability is a key aspect of the design with a 125 year service life specified. One of the most significant factors in the design, however, is the compressed construction schedule. The crossing is scheduled to open to traffic on 1 December 2018, with the notice to proceed announced in May 2015, permitting a total design and construction duration of just 42 months. Key elements of the design and construction which allow the project to be completed within the short timeframe, while meeting the challenges of environmental constraints, durability requirements and architectural considerations, are explored in this paper. [ABSTRACT FROM AUTHOR]

Accurate estimation of wind-driven rain (WDR) load on building facades is of paramount importance for the assessment of moisture-induced damage risks. The response of the facade depends on the used meteorological data, which can show significant variation over time, especially considering climate change. In this study, a statistical approach based on a Latin Hypercube Sampling (LHS) is used to generate reduced samples, which accurately represent long-term meteorological conditions for WDR. Based on cumulative distribution functions, the generated samples with LHS are a subset of actual measured data, independent of the temporal information, and are clustered around values of highest frequency. Computational fluid dynamics (CFD) simulations of WDR are performed on a historical building located in Victoria, BC, Canada based on a previously validated methodology, determining the parts of facade receiving the highest WDR load. The sensitivity study shows that a sample size of 200 with LHS, corresponding to around 0.2% of the total measured data and 4.1% of the data during rainfall, is sufficient to replicate successfully the spatial distribution of WDR with a maximum discrepancy of 7%. The reduced samples can be easily modified to model various scenarios with respect to the climate change. The change in WDR load is presented for different scenarios in terms of rainfall intensity and wind speed as predicted by future climatic conditions. The results indicate that the future WDR load depends highly on the wind speed conditions, even when wind speed is kept constant and only rainfall intensity is varied. • Long-term representative data are generated with Latin Hypercube Sampling. • The generated reduced samples successfully replicate wind-driven rain load. • 4% of measured rain data is enough to replicate wind rose and driving-rain index. • Largest impact on future wind-driven rain load is when the wind velocity changes. • Change in catch ratio at increased future rainfall intensity depends on wind speed. [ABSTRACT FROM AUTHOR]

Pyramiding multiple resistant genes has been proposed as the most effective way to control wheat rust diseases globally. Identifying the most effective pyramids is challenged by the large pool of rust resistance genes and limited information about their mechanisms of resistance and interactions. Here, using a high-density genetic map, a double haploid population, and multi-rust field testing, we aimed to systematically characterize the most effective gene pyramids for rust resistance from the durable multi-rust resistant CIMMYT cultivar Parula. We revealed that the Parula resistance gene pyramid contains Lr34/Yr18/Sr57 ( Lr34 ), Lr46/Yr29/Sr58 ( Lr46 ), Lr27/Yr30/Sr2 ( Sr2 ), and Lr68 . The efficacy, magnitude of effect, and interactions varied for the three rust diseases. A subpopulation mapping approach was applied to characterize the complex interactions of the resistance genes by controlling for the effect of Lr34 . Using this approach, we found that Lr34 and Lr68 have a strong additive effect for leaf rust, whereas no additive effects were observed for any rusts between Lr34 and Lr46 . Lr34 combined synergistically with Sr12 from Thatcher for stem rust, whereas the additive effect of Lr34 and Sr2 was dependent on the type of rust and environment. Two novel leaf rust quantitative trait loci (QTLs) from Parula were identified in this study, a stable QTL QLr-7BS and QLr-5AS , which showed Lr34 dependent expression. With these findings, we propose combining two to three high-value genes from Canadian wheat (e.g., Sr12 from Thatcher) with a foundational multi-adult plant resistance cassette for desirable and durable resistance to all three rusts in Canadian wheat., Competing Interests: The author(s) declare no conflict of interest.

• North American five needle white pines are very susceptible to white pine blister rust (WPBR). • Seedlots with genetic resistance to WPBR are needed for restoration. • The level and type of genetic resistance to WPBR varies greatly by species. • Restoration efforts for some species has begun. • Genomic resources offer promise to develop resistant populations in the future. All nine five-needle white pine species (genus Pinus , subgenus Strobus , subsections Strobus and Balfourianae) native to the U.S. and Canada are highly susceptible to white pine blister rust (WPBR), caused by the non-native fungal pathogen Cronartium ribicola. WPBR is present within the geographic range of eight of the nine species in the U.S. including the four species also present in Canada, but has not yet been documented in Mexico. Genetic resistance to WPBR has been documented in eight of the white pine species present in the U.S., with extensive work on foxtail pine (Pinus balfouriana) just recently started. The development of populations of trees with durable genetic resistance, while also retaining genetic diversity and adaptability, is seen as a fundamental step in restoring white pine species. Major gene resistance (MGR) has been documented in four species, and quantitative resistance (QR) is likely present in all species, but at levels ranging from very low to moderately high. Restoration using seed from WPBR resistant parent trees has been underway for several decades for western white pine (P. monticola), sugar pine (P. lambertiana) , and eastern white pine (P. strobus), and has begun more recently for whitebark pine (P. albicaulis) and limber pine (P. flexilis). For many of these white pine species, locating additional resistant parents and acquiring more seed will be needed over the ensuing decades. The previous efforts in developing populations of trees with genetic resistance to WPBR has used conventional tree improvement techniques of tree selection and seedling inoculation trials. However, in the future with the continued development of omics resources and tools in white pines, biotechnology has the potential to aid resistance programs. Candidate genes have been identified for host MGR, QR, and disease susceptibility (S) to WPBR, as well as for C. ribicola effectors. Marker-assisted selection (MAS) tools developed from MGR-linked genes would be useful to combine MGR and QR, which should improve the potential durability of resistance. Integration of breeding programs with omics information and tools can help pave a road towards improvement of WPBR resistance through biotechnological approaches such as MAS, and genomic selection (GS), or potentially helping to incorporate unique resistance not currently found in North American five-needle white pines. In the near future, these tools could potentially aid in the initial search for candidate trees which would increase the efficiency of developing WPBR resistant populations, as well as defining the extent and distribution of adaptive genetic variation in the species, which will aid in planning restoration efforts. [ABSTRACT FROM AUTHOR]

Abstract: In Part 1 of this paper, a carbonation model was developed and experimentally verified which was able to forecast carbonation depth of a concrete specimen considering varying ambient temperature, humidity and CO2 concentrations. Part 2 of the paper applies the carbonation diffusion/reaction model developed in Part 1 to predict the effects of global climate change on the carbonation of concrete. Climate scenarios were formulated and combined with the model for two major Canadian cities, Toronto and Vancouver. Results show that for undamaged and unstressed concrete, climate change will significantly affect carbonation progress. The model showed that for unloaded, non-pozzolanic concrete, ultimate carbonation depths in Toronto and Vancouver could be up to 45% higher. For in-service structures under load, the rates of deterioration are likely to be even faster. This is a cause for concern, and much further effort must be devoted to fully understand these phenomena. [Copyright &y& Elsevier]

This paper presents a laboratory investigation on the durability and structural performance of carbon fibre reinforced polymer (CFRP) - reinforced concrete (RC) slab specimens extracted from the Laurier-Taché Parking Garage (in the National Capital Region, Canada) after being subjected to service field conditions for about 8 years (1997-2005). The laboratory investigation comprised two phases. The first phase evaluated the durability of the CFRP bars, the concrete, and the interface between the two materials by conducting microstructural and chemical analyses on core samples extracted from the slabs. As part of this phase, five CFRP bar samples were extracted and tested in tension to investigate if the CFRP bars experienced any degradation in strength or stiffness. The second phase investigated the structural behaviour of the slabs by testing four slab segments (3.0 m long × 1.0 m wide × 0.2 m deep) in flexure. Test results showed that neither the CFRP bars nor the CFRP-RC slabs have been adversely affected after being in service for 8 years. [ABSTRACT FROM AUTHOR]

The mix design of ultra-high performance fibre reinforced concretes (UHPFRC) produced with locally available materials in Quebec and Ontario is presented. The procedure and results of the optimization of self-consolidating UHPFRC are discussed. The characterization of the retained mixes is presented with regards to strength, heat of hydration, shrinkage, chloride ion permeability, and freeze-thaw resistance. The results show that it is possible to produce self-consolidating UHPFRC with the targeted properties for use in precast products and in situ applications without requiring heat or pressure treatment during curing. [ABSTRACT FROM AUTHOR]

The article focuses on the results of an experiment evaluating the performance of fly ash (FA) produced from processed petroleum coke, and coal-only combustion for compliance in the Canadian Standard Association requirements. Beneficiated petroleum coke FA was shown in every aspect to meet the concrete manufacturing standards. The results showed that pet coke FA has no solid difference in performance to coal-only FA. The results propose consideration in the extended definition of FA.

The Wood Innovation Research Lab was designed as a low energy-use building to facilitate the construction and testing of engineered wood products by the faculty and staff of the Master of Engineering in Integrated Wood Design Program at the University of Northern British Columbia in Prince George, BC, Canada. Constructed using a 533 mm thick-wall and 659 mm flat roof assembly, it received certification as Canada's first industrial facility built to the International Passive House standard. Temperature and humidity sensors were installed in the north and south exterior wall assemblies to measure long-term hygrothermal performance. Data collected between 2018–2020 shows no record of long-term moisture accumulation within the exterior assemblies. Data collected during this time period was used to validate hygrothermal performance models for the building created using the WUFI® Plus software. Long-term performance models created using future climate data for five cities across Canada under two global warming scenarios shows favorable results, with an increase in average annual temperatures resulting in lower average relative humidity values at the interior face of the exterior sheathing board in the exterior wall assemblies. [ABSTRACT FROM AUTHOR]

• Adding slag improved the compressive and split-tensile strengths. • Adding slag increased the flexural strength and enhanced post-cracking behavior. • SEM images suggest that PVA fibres exhibit frictional debonding in slag ECC mixture. • Slag was effective in reducing the chloride ion penetration and water sorptivity. • The ASR expansion of all ECC mixtures was rated as harmless as per ASTM C1260. The need for sustainable power generation resources is increasing day after day. Among many countries around the world, Canada is considering elimination of coal plants. This is causing a shortage in the supply of good quality fly ash minerals. Recent research on the production of engineered cementitious composites (ECC) focused on utilizing of Class F Fly Ash. Hence, this study was designed to experimentally investigate the influence of partial and full replacement of slag with fly ash on the mechanical and durability performance of ECC mixtures through a comprehensive experimental program. Test results from this study showed that slag containing mixtures exhibited strain-hardening behaviour and a comparable or similar ductility characteristics as fly ash containing mixtures. Moreover, incorporating slag in the mixtures were found to be effective in reducing permeability in terms of rapid chloride penetration, sorptivity, and water absorption at both 28 and 90 days. However, mixtures containing slag had higher drying shrinkage strains when compared to fly ash mixtures. [ABSTRACT FROM AUTHOR]

Sustainable building practices are rooted in the need for reliable information on the long-term performance of building materials; specifically, the expected service-life of building materials, components, and assemblies. This need is ever more evident given the anticipated effects of climate change on the built environment and the many governmental initiatives world-wide focused on ensuring that structures are not only resilient at their inception but also, can maintain their resilience over the long-term. The Government of Canada has funded an initiative now being completed at the National Research Council of Canada's (NRC) Construction Research Centre on "Climate Resilience of Buildings and Core Public infrastructure". The outcomes from this work will help permit integrating climate resilience of buildings into guides and codes for practitioners of building and infrastructure design. In this paper, the impacts of climate change on buildings are discussed and a review of studies on the durability of building envelope materials and elements is provided in consideration of the expected effects of climate change on the longevity and resilience of such products over time. Projected changes in key climate variables affecting the durability of building materials is presented such that specifications for the selection of products given climate change effects can be offered. Implications in regard to the maintainability of buildings when considering the potential effects of climate change on the durability of buildings and its components is also discussed. [ABSTRACT FROM AUTHOR]

Background Recurrent Clostridium difficile infections (rCDI) are a public health threat with insufficient treatment options at present. Two Phase 2 clinical studies have reported the efficacy of RBX2660, a standardized, stabilized microbiota-based drug, in preventing rCDI. For one of these trials, we report herein the durability of clinical response (lack of CDI recurrence) and microbiome restoration to 12 months after RBX2660 treatment. Methods Data were drawn from an interim analysis of a multicenter, open-label Phase 2 study in which participants with multi-recurrent rCDI received up to 2 doses of RBX2660 delivered via enema 7 days apart; this analysis includes data to 12 months after treatment, with follow-up ongoing. Efficacy was defined as the absence of CDI recurrence to 56 days after the last dose; and durability is defined as a continued lack of reported recurrence. Participant stool samples collected prior to and at 1, 7, 30, 60 days and 6 and 12 months after treatment were sequenced using a shallow shotgun method, with only treatment responders reported herein. Operational taxonomic unit (OTU) data were used to calculate relative abundance at the class level and Microbiome Health Indices. Results This study included 149 RBX2660-treated participants and 110 historical control patients, in the United States and Canada. As previously reported, the efficacy of RBX2660 in preventing rCDI (79.9%; 119/149) was higher than CDI-free rates in the historical control group (51.8%, 57/110; P < 0.001). Of 109 participants who had a 6-month follow-up, 97.2% (106/109) remained CDI-free, and no new CDI recurrences were reported at 12 months. Among treatment responders, the microbiome composition was restored after treatment to predominance by Bacteroidia - and Clostridia -class bacteria, and these compositions remained stable to 12 months after treatment among participants who provided samples. Conclusion RBX2660, a microbiota-based drug, was efficacious for preventing rCDI, with clinical and microbiome restoration durability to at least 12 months after treatment. The follow-up of efficacy, safety, and microbiome restoration are ongoing. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]

Climate change has led to governments mandating greater energy efficiency in building codes throughout Canada and the US. Increased energy efficiency requires a high level of insulation of the building envelopes, which may introduce unintended durability concerns. To investigate potential durability issues, six types of high thermal resistance (High RSI) wall assemblies were tested at a building envelope test facility. This study compares the hygrothermal performance of conventional 38 × 140 mm framing (i.e. baseline wall) with three types of deep cavity walls and three types of exterior insulated walls. The wall assemblies tested have an average installed thermal resistance of RSI 6.8 and they were installed at both north and south-facing orientations of the building envelope test facility to observe their relative performance. The hygrothermal conditions of test walls were monitored under three consecutive periods: baseline period without air leakage in fall/winter time, air leakage period with air injection in winter/spring time, and drying period without air leakage in spring time. The hygrothermal performance in terms of moisture content profile of OSB sheathing and mold growth risk at the interior surface of OSB sheathing was analysed with respect to wall types and orientation. The exterior insulated walls had lower moisture content than deep cavity walls and the baseline wall throughout the whole monitoring period, and there was no condensation or mold growth risk under simulated air leakage. Although the deep cavity walls had higher moisture content levels than the baseline wall, they were less responsive to air leakage than the baseline wall due to the hygroscopic characteristics of cellulose fiber insulation installed in the stud cavity. The deep cavity walls had higher risk of moisture problems than the baseline wall and the exterior insulated walls. • Hygrothermal performance of highly insulated wood framed walls was investigated through field measurement. • Effect of air leakage was investigated by injecting indoor air into wall assemblies. • Exterior insulated walls were less responsive to air leakage than deep cavity walls. • OSB sheathing in deep cavity walls had higher moisture content than that in exterior insulated walls. • Deep cavity walls have greater mold growth risks than exterior insulated walls. [ABSTRACT FROM AUTHOR]

Canadian-based PowerDisc Development Corporation says that its novel eFlow™ PEM fuel cell design solves one of the most challenging issues in the fuel cell industry: unequal current distribution. By improving the flow of oxygen, fuel and water, fuel cells using eFlow can avoid the degradation seen in fuel cell membranes and other stack materials. This results in increased durability, higher peak power, and reduced cost due to improved membrane resiliency and lifetime. [ABSTRACT FROM AUTHOR]