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Reports on the determination of structure, height and diameter growth, above-and below-ground biomass and nutrient distribution of a paper birch and subalpine fir mixed species stand in the Sub-Boreal Spruce zone of British Columbia. Findings that suggest normal distribution of height and diameter in paper birch; Distribution pattern of subalpine fir; Total biomass of both plants.

Growth and survival responses of 8 year-old interior spruce to reductions in paper birch density from 2500 to 1000, 50 and 0 overtopping stems ha[sup -1] were examined after five years on a single site in the Interior Cedar Hemlock biogeoclimatic zone of southern British Columbia. Stem diameter increased and height: diameter ratio decreased when birch density was reduced from 2500 to 50 stems ha[sup -1], but there were no further benefits to spruce growth when the entire birch overstory was removed. Spruce growth did not improve where birch was thinned to 1000 stems ha[sup -1], but its potential for release may have been confounded by the higher density of taller conifers in that treatment. Interspecific competition between spruce and paper birch appeared to be primarily for light because spruce responded to dramatic reductions in overstory density but not to reductions in understory sprout density. Spruce survival was unaffected by thinning treatments, indicating that birch density of 2500 stems ha[sup -1] was too low to induce mortality. Armillaria root disease was the main cause of mortality, and spruce leader weevil and Cooley's spruce gall adelgid were important damaging agents, but the behaviour of these organisms was unaffected by treatment. Stand structure was dramatically changed from a mixed coniferous-deciduous to a predominantly coniferous overstory when birch was thinned to 50 or 0 stems ha[sup -1], which may have negative implications for wildlife. If balancing maximum spruce growth with biodiversity is the primary objective, then between 50 and 1000 stems ha[sup -1] birch should be retained on sites similar to the one used in our experiment. This will require modification of the current legislation governing reforestation in British Columbia. [ABSTRACT FROM AUTHOR]

• 72% − 80% of fibre was recovered from disposable coffee cups. • 2% and 3% consistency shredded cups required > 100 kWh/tonne to repulp with 3 refiner passes. • Pulp quality did not significantly diminish after repulping using a single-disk refiner. Over 64 billion paper-plastic laminate (PPL) coffee cups are consumed between the United States and Canada annually, the majority accumulating in landfills due to a hydrophobic plastic inner-lining. Recycling can mitigate environmental damage and provide economic value from repurposed products. We found that standard repulping methods were insufficient to separate fiber from plastic due to the low intensity of treatment. To increase process intensity, we mechanically refined shredded PPL coffee cups and Kraft eucalyptus sheets (control) at 2%, 3%, and 4% consistencies with three passes to determine the energy required to separate fibers from plastic and the effects on fiber quality. 2% and 3% consistency PPL cups measured under 40 kWh/tonne of input material for one refiner pass and ∼ 80 kWh/tonne for 4% consistency PPL cups. Recovered fiber fraction totaled 87.7%, 85.3%, and 80.5% of input mass of Kraft eucalyptus and 72.3%, 72.6%, and 79.6% of input mass of PPL cups at 2%, 3%, and 4% consistency, respectively. Fines content of PPL cups jumped from 8% pre-refining to ∼ 30% post-refining while Kraft eucalyptus fibers were unaffected, suggesting that breaking the plastic-fiber bonds results in fines generation. Mean fiber length of PPL cups slightly decreased with consistency and tensile strength improved. Freeness decreased with consistency only in PPL cup samples. These results demonstrate a low energy requirement to effectively separate fiber and plastics in PPL cups as well as minimal impact on fiber quality using existing refining technology, and provides an estimate of the financial costs of local recycling efforts. [ABSTRACT FROM AUTHOR]

A vast amount of articles centered on brain metastases have been published. To present the 100 most-cited articles dedicated to brain metastasis and to accomplish a broad literature review. In December 2019, we performed a title-focused search using the Thomson Reuters Web of Science database to identify the most cited articles centered on brain metastatic disease. Our search query term was based on using the following algorithm: "brain metastases" OR "brain metastasis" OR "brain metastatic disease" OR "cerebral metastases" OR "cerebral metastasis" OR "cerebral metastatic disease." Afterward, we reviewed the results to certify that they were relevant to the purposes of our research protocol. The 100 most cited papers were chosen and further analyzed. Our search resulted in 11,579 articles, published from 1975 until the completion of our survey. The most cited article, by Patchell et al., was published in 1990, with 1862 citations, and an average of 62.07 citations per year, whereas the last in our list, by Gaspar et al., was published in 2010, with 195 total citations, and an average of 19.50 citations per year. Countries with the highest-cited articles included the United States (75 records), followed by Canada (16 records). We discovered the top 100 most-cited articles centered on brain metastasis, all of which show a potentially increased level of interest, because they are meaningful scientific reports. In addition, we reviewed the historical development and advances in brain metastasis research and relevant points of interest, alongside the relevant contributions of different authors, fields of special interest, and countries. Many of the most cited articles were written by authors whose specialty was not neurosurgery or by neurosurgeons who were supported by colleagues from other medical fields. As a consequence, many of these articles were not published in neurosurgery-dedicated journals. [ABSTRACT FROM AUTHOR]

Efforts to prevent work-related injuries have met with tangible success in industrialized countries. In Quebec, workplace accidents and occupational illness have declined sharply since the end of the 1990s. However, there is still considerable room for improvement in small and medium-sized enterprises (SMEs). Expert specialists in accident prevention in SMEs are overloaded. Their interventions are repetitive and not personalised. Few tools are available for accelerating the process of evaluating occupational health and safety (OHS) performance. The aim of this research project was to address this deficiency by proposing a novel OHS performance evaluation tool better adapted to SMEs. For this purpose, research was carried out in two distinct phases. The first phase led to the theoretical model on which the tool is based. The second phase was carried out using an action research approach. The proposed tool was designed and improved during this phase, through field-testing and the involvement of a Quebec industrial partner. In spite of the limitations of this research, we have succeeded in developing a new tool with software support adapted specifically for the evaluation of OHS performance in SMEs. Upon completion of the project, a tested and improved version of the tool was delivered to the industrial partner. Experts in accident prevention have found the tool to be reliable and helpful. It has accelerated the identification of deficiencies in OHS management in several SMEs and has helped specialists to develop personalized and better-focused plans of action. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel method to estimate total technical potential for improving energy efficiency. • Bottom-up sector energy model used to characterize energy demands and opportunities. • Technology-explicit analysis framework used to estimate integrated energy savings. • Application to Canada's pulp & paper sector indicates major savings are possible. • Technical potential to reduce natural gas use by 95% and net electricity by 54% Industrial energy efficiency has long been recognized as a critical tool for energy management and emissions reduction and is increasingly considered to be an energy resource in its own right. However, the complexity of most industrial sectors creates barriers for modellers, companies, and policymakers in understanding and achieving the overall potential for efficiency-driven energy savings. To address this gap, we have developed a novel method that combines disaggregated bottom-up sector energy modelling with analysis of a comprehensive set of technology-explicit energy efficiency measures. This approach overcomes the deficiencies of top-down analyses and better represents the complexities of multi-measure efficiency investments compared to piecewise studies of individual measures. In this study, we demonstrated application of our method to the case of the Canadian pulp and paper sector. Our analysis shows that the sector can reduce its natural gas and electricity use by 95% and 41%, respectively, by adopting economical efficiency measures. This equates to 71 PJ of natural gas and 44 PJ of electricity saved annually and would result in cost savings of $81 per tonne of output sector-wide. Notably, we find that efficiency and fuel switching have the technical potential to reduce natural gas consumption by 98% across the sector. Taken together, the results provide quantitative evidence that energy efficiency is an underestimated resource for cost-effective energy savings in the Canadian pulp and paper sector. Our analysis framework can be applied to any industrial sector in any region to provide insights regarding energy conservation strategies and policy design. [ABSTRACT FROM AUTHOR]

Abstract: Canada's commercial seal hunt warrants close examination in that it is the largest kill of marine mammals on earth, it exists for commercial reasons, it targets deep diving seals with unique physical adaptations, and it is conducted in a particularly remote and uncontrolled environment amidst unstable sea ice and extreme weather conditions. For these reasons, commercial sealing in Canada has been the subject of regular veterinary scrutiny for more than five decades. In that time, despite repeated recommendations and some changes to the regulations, considerable evidence continues to be presented during each new season of poor welfare outcomes for seals. To add to the discussion we (Butterworth and Richardson) (2013) [1] reviewed multiple studies on commercial sealing, government reports, trade journal articles and recommendation reports, in an attempt to answer the question of why, despite the efforts of veterinary advisors and government to improve the situation, seals continue to die in inhumane ways. In examining the available evidence, the environment in which commercial sealing occurs, and the physical adaptations of seals, the authors concluded that generally accepted principles of humane slaughter cannot be implemented effectively and consistently in the context of commercial sealing. [Copyright &y& Elsevier]

Abstract Scope Antibiotic stewardship programmes (ASPs) are necessary in hospitals to improve the judicious use of antibiotics. While ASPs require complex change of key behaviours on individual, team organization and policy levels, evidence from the behavioural sciences is underutilized in antibiotic stewardship studies across the world, including high-income countries (HICs). A consensus procedure was performed to propose research priority areas for optimizing effective implementation of ASPs in hospital settings using a behavioural perspective. Methods A workgroup for behavioural approaches to ASPs was convened in response to the fourth call for leading expert network proposals by the Joint Programming Initiative on Antimicrobial Resistance (JPIAMR). Eighteen clinical and academic specialists in antibiotic stewardship, implementation science and behaviour change from four HICs with publicly funded healthcare systems (e.g. Canada, Germany, Norway and the UK) met face-to-face to agree on broad research priority areas using a structured consensus method. Question addressed and recommendations : The consensus process assessing the ten identified research priority areas resulted in recommendations that need urgent scientific interest and funding to optimize effective implementation of ASPs for hospital inpatients in HICs with publicly funded healthcare systems. We suggest and detail behavioural science evidence–guided research efforts in the following areas: (a) comprehensively identifying barriers and facilitators to implementing ASPs and clinical recommendations intended to optimize antibiotic prescribing; (b) identifying actors ('who') and actions ('what needs to be done') of ASPs and clinical teams; (c) synthesizing available evidence to support future research and planning for ASPs; (d) specifying the activities in current ASPs with the purpose of defining a control group for comparison with new initiatives; (e) defining a balanced set of outcomes and measures to evaluate the effects of interventions focused on reducing unnecessary exposure to antibiotics; (f) conducting robust evaluations of ASPs with built-in process evaluations and fidelity assessments; (g) defining and designing ASPs; (h) establishing the evidence base for impact of ASPs on resistance; (i) investigating the role and impact of government and policy contexts on ASPs; and (j) understanding what matters to patients in ASPs in hospitals. Conclusions Assessment, revisions and updates of our priority-setting exercise should be considered at intervals of 2 years. To propose research priority areas in low- and middle-income countries, the methodology reported here could be applied. [ABSTRACT FROM AUTHOR]

The article presents a synopsis on comprehensive non-surgical treatment which leads to improved walking ability in people with lumbar spinal stenosis. Topics discussed include dominant symptom of people with lumbar spinal stenosis; marginal differences between treatment groups in other more traditional outcomes; and training program offered to the comprehensive training and motivated patients.

Highlights: [•] Evaluation of new HWP accounting method leads to significant GHG emission reduction for Canada. [•] Use of harvested wood for energy and of construction lead to largest GHG savings. [•] A cascade-use for wood and paper products is paramount for further GHG improvement. [•] The end-of-life effect of using recycled waste wood for energy is delayed due to longer carbon uptake. [•] Cradle-to-cradle utilization of wood waste has an underdeveloped reduction potential. [ABSTRACT FROM AUTHOR]

In today's globalized world wood-based products are often imported from countries other than those where the wood was grown. Bilateral trade statistics are thus only of limited help for getting a better understanding of how production-related environmental impacts are caused by consumption elsewhere. This study presents a novel physical accounting model that allows flows of wood-based products to be traced along international supply chains, therefore making it possible to consistently relate the consumption of wood-based products to the origin of roundwood. In comparison to previous studies, the proposed method covers entire supply chains, including finished wood and paper products, such as furniture and printed matter, and also accounts for flows of processing residues and recovered paper. The main results of the accounting model are detailed country-by-country matrices indicating the locations of origin of the products consumed in a given nation. For instance, it is revealed that out of the finished wood products consumed in the USA in 2018, 75.6% originated domestically, 10.7% from neighbouring Canada and the remaining 13.7% from other countries. Potential applications and extensions of the presented approach are also discussed. • The accounting approach traces flows of wood-based products along supply chains. • The method has a high regional resolution and covers 16 different products. • Processing residues, recovered paper and finished products are also accounted for. • Matrices indicate the origin of the raw material contained in consumed products. • The model is useful for investigating the theory of unequal ecological exchange. [ABSTRACT FROM AUTHOR]

On-demand transit (ODT) has been widely piloted in recent years by many transit agencies in response to changing travel behaviour and preferences among people. Some agencies have adopted ODT to replace underperforming bus routes, as part of a continuous service planning process while others incorporated it within network re-design. All these trends highlight the critical need for transit agencies to have guidance for incorporating ODT into transit network planning both at the strategic, tactical, and service planning levels. Thus, the purpose of this research is to provide a discussion of the key guiding principles to facilitate the development of transit networks with integrated on-demand and scheduled services. To achieve this goal, a thorough review of the states of practice and research was conducted. Findings from the practice review were also reinforced through ODT practitioners' engagement in Canada. This paper provides discussions on the service goals and objectives of an integrated network design and highlights the key planning requirements for developing integrated networks. At the service planning level, the paper provides a discussion on service goals, service design parameters, and scenario development of ODT service. • On-demand transit (ODT) have grown in many cities around the globe, mostly as pilot projects. • Review of the literature and practice shows that planning for ODT is based on best practices , without "built" guidelines. • Principles of planning are discussed within two applications, the network design level, and the service planning level. • Opportunities of integration and mode selection criteria are defined to integrated ODT with existing bus network. • Simulation and analytical tools are useful to complement the principles of planning in the decision-making processes. [ABSTRACT FROM AUTHOR]

Abstract: The Sydney Steel Plant emitted toxic pollutants into the local area for almost 100 years. Although no paper record exists of the amount and spatial variability of the pollutants emitted, a natural record exists locked in the annual growth of native tree species in the region. Studies have shown that temperate trees can incorporate local metal pollution into their annual rings, creating a temporal and spatial record of the pollution. Two abundant species were sampled within a 5-km radius of the steel plant site. Using dendrochronology, atomic absorption spectroscopy (AAS) and energy dispersive X-ray fluorescence (EDXRF) on white birch, Betula papyrifera, and eastern larch, Larix laricina, a new methodology was developed to determine levels of pollutants in a given year. Atomic absorption spectroscopy did not produce accurate results with the small sample sizes we were able to process, but energy dispersive X-ray fluorescence determined that the hardwood birch better incorporated both lead and zinc into annual rings than the softwood larch. The technique provides an interesting area for further study, because it provides a time efficient and repeatable method of analyzing chemicals stored in wood tissue. [ABSTRACT FROM AUTHOR]

Abstract: Hemlock looper (Lambdina fiscellaria fiscellaria (Guen.)) is an economically damaging defoliator that undergoes periodic outbreaks in Newfoundland, Canada. It defoliates and causes extensive tree mortality to its primary host, balsam fir (Abies balsamea [L.] Mill.). We quantified tree survival using data from permanent sample plots (PSPs) and growth reduction or release using dendrochronology, and related these impacts to defoliation severity determined from annual aerial defoliation survey data. Such impact relationships are necessary as a fundamental input to a Decision Support System. Growth and survival of balsam fir, black spruce (Picea mariana (Mill.) B.S.P.) and white birch (Betula papyrifera Marsh.) were assessed from 1996 to 2008 in 48 Newfoundland Forest Service PSPs, selected based on four classes of defoliation severity. Two years of severe (71–100%) defoliation resulted in almost complete mortality for balsam fir, 10 years after defoliation, whereas survival was 70–80% for black spruce and white birch. Lower defoliation severity (1–2 years of moderate (31–70%) or 1 year of severe) resulted in approximately 60% survival for balsam fir and no reduction in survival for black spruce and white birch. Maximum growth reduction of balsam fir was 10–15% with 1 year of moderate-severe defoliation, 35–40% with 2 years of moderate defoliation, and about 50% with 2 years of severe defoliation. Growth recovered to pre-defoliation rates 5 years after defoliation ceased in all severity classes. Growth reduction and recovery of black spruce were more variable and lower than for balsam fir, and white birch exhibited only minor (<10%) growth reduction during the defoliation year or 1 year after defoliation. Control measures should focus on avoiding severe defoliation for two consecutive years. [Copyright &y& Elsevier]

Abstract: Postfire tree species compositions are predicted to be the same prior to fire according to the direct regeneration hypothesis (DRH). We studied 94 upland boreal forest stands between 5 and 18 years after fire in Ontario, Canada. Postfire species-specific regeneration density was positively related to prefire stand basal area for Pinus banksiana, Populus spp., Betula papyrifera and Picea mariana, but not for Picea glauca and Abies balsamea. In addition, seedling density of Populus spp., B. papyrifera, P. mariana, P. glauca and A. balsamea were positively affected by build up index and, except Populus spp., their density increased with age of burn. To facilitate testing the DRH, we introduced a term called compositional difference (CD) that is the difference in a species relative percentage between the postfire and prefire stand. The testable null hypothesis is CD=0 for a given species. CD was not different from 0 for P. banksiana, was 19.8% for Populus spp., 10.4% for B. papyrifera, −17.9% for P. mariana, −14.6% for P. glauca, and −14.9% for A. balsamea, indicating fire increases broadleaves at the expenses of mid- and late-successional coniferous species. Compositional increases of Populus spp. and B. papyrifera in postfire stands occurred mostly where these species were a minor component prior to fire. In conclusion, the DRH was supported by the specific positive relationships between postfire regeneration densities and prefire basal area for P. banksiana, Populus spp., B. papyrifera and P. mariana. However, if the DRH is used for predicting postfire composition, P. banksiana is the only species that had the same composition between postfire and prefire stands. Nevertheless, CD for P. banksiana was negatively related to its prefire composition. Similarly, CD for other species was negatively related to their prefire compositions with varying effects of build up index and age of burn. Our results suggest, if fire occurrences increase with global change, the boreal landscape will be more dominated by hardwoods and mixtures of conifers and hardwoods. [Copyright &y& Elsevier]

This paper examines whether a forced displacement of an ethnic group can lead to long-run changes to their spatial distribution and whether this shock can also lead to changes in where new migrants settle. I use the Canadian government's internment of Japanese Canadians during World War II, as well as their post-war forced resettlement, as a natural experiment. I find that the policy led to dramatic resettlement patterns; areas where Japanese Canadians were removed from had far fewer Japanese Canadians after World War II, with this effect persisting for decades. Despite these displacement patterns, I find that both the pre-war and post-war settlement patterns drive where new Japanese migrants settle within Canada, suggesting that the disruption of the connections and networks formed by Japanese migrants before World War II were not fully dismantled by the Canadian government's wartime policies. Reinforcing this mechanism, I show using Facebook's social connectedness data that Japanese population shares from both 1931 and 1951 predict whether a Canadian Census Division is more socially connected with Japan today. The results from this paper show that, despite Canada's forced dispersal of its Japanese population across the country, networks and forces that connect Census Divisions to Japan and draw in new migrants continued to persist. [ABSTRACT FROM AUTHOR]

Direct air capture of carbon dioxide (CO 2) is technically a feasible solution for reducing atmospheric CO 2 concentrations at scale, building on decades of global research. However, powering such systems even partially with CO 2 -intensive fossil fuels results in more CO 2 emissions. This paper presents a novel energy management strategy (EMS) to further explore modular offshore wind energy off Canada's West Coast via power-to-direct air capture and power-to-gas systems. The system architecture includes a 15 MW wind turbine paired with a hydrogen energy storage system, i.e. hydrogen production and storage, and direct air capture (DAC) units. Hydrogen production from wind generation is stored and used to offer two key benefits: to deliver the thermal loads of the DAC system, and to meet hydrogen demand for external consumers. The proposed EMS offers an extra degree of freedom to operate the designed system by setting the priority either to maximize the amount of CO 2 capture or to maximize the amount of H 2 production for external consumers. In particular, the study incorporates dynamic mathematical modeling and constraints formulation for the aforementioned scenarios; DAC priority for CO 2 capture and H 2 for external hydrogen demand satisfaction. The effectiveness of the proposed EMS is shown through extensive simulations with different seasonal conditions. • Detailed mathematical dynamical models for offshore power-to-DAC and power-to-gas systems. • Green hydrogen production for two-fold benefits; H 2 for meeting DAC thermal loads, and H 2 as fuel for external consumers. • Scenario 1 prioritize the CO 2 capture rate, while scenario 2 maximizes the H 2 production for external consumers. • Design of EMS shows the correct unit commitment of the CO 2 capture rate and H 2 tracking. [ABSTRACT FROM AUTHOR]