Search

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

Lake ice phenology (timing of ice breakup and freeze up) is a sensitive indicator of climate. We acquired time series of lake ice breakup and freeze up, local weather conditions, and large-scale climate oscillations from 1981–2015 for seven lakes in northern Wisconsin, USA, and two lakes in Ontario, Canada. Multiple linear regression models were developed to understand the drivers of lake ice phenology. We used projected air temperature and precipitation from 126 climate change scenarios to forecast the day of year of ice breakup and freeze up in 2050 and 2070. Lake ice melted 5 days earlier and froze 8 days later over the past 35 years. Warmer spring and winter air temperatures contributed to earlier ice breakup; whereas warmer November temperatures delayed lake freeze. Lake ice breakup is projected to be 13 days earlier on average by 2070, but could vary by 3 days later to 43 days earlier depending upon the degree of climatic warming by late century. Similarly, the timing of lake freeze up is projected to be delayed by 11 days on average by 2070, but could be 1 to 28 days later. Shortened seasonality of ice cover by 24 days could increase risk of algal blooms, reduce habitat for coldwater fisheries, and jeopardize survival of northern communities reliant on ice roads. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to explore institutional realities and public perceptions of police use of unmanned aerial vehicles (UAVs) in Canada in relation to each other, drawing attention to areas of public misunderstanding and concern.Design/methodology/approach Public perceptions data are drawn from a national survey (n=3,045) of UAV use. Institutional realities data are drawn from content analyses of all Special Flight Operation Certificates issued by Transport Canada from 2007 to 2012 and flight logs of a regional service kept from 2011 to 2013. Officer interviews (n=2) also provide qualitative insights on institutional realities from this same regional service.Findings The data reveal disparities between institutional realities and public perceptions. Although federal, provincial and regional services currently use UAVs, awareness of police use of UAVs relative to traditionally piloted aircraft was low. Further, support for police use of UAVs was significantly lower than traditionally piloted craft; but, support also varied considerably across UAV applications, with the greatest opposition tied to tasks for which police do not report using UAVs and the greatest support tied to tasks for which police report using UAVs.Originality/value This research provides previously unknown descriptive data on the institutional realities of police use of UAVs in Canada, positioning that knowledge in relation to public perceptions of police use of the technology. The findings raise concerns over how UAVs may negatively shape police/civilian relations based on procedural justice literature which demonstrates that a lack of public support for the technology may affect the police more broadly. [ABSTRACT FROM AUTHOR]

The effects of long duration simulated motion on motor task and neuromuscular performance along with time frames required to recover from these effects are relatively unknown. This study aimed to determine (1) how simulated motion affects motor task and neuromuscular performance over one hour of motion and (2) the time course of recovery from any decrements. The dependent variables that were measured included: reaction time; visuomotor accuracy tracking; maximal voluntary contractions; voluntary activation; evoked contractile properties and biceps brachii electromyography of the elbow flexors. Reaction times and error rates of the visuomotor accuracy tracking task were compromised in motion, but maximal force, voluntary activation, evoked contractile properties and rmsEMG responses of the biceps brachii were unaffected by motion. It is concluded that motion causes an increase in attention demands, which have a greater effect on motor task rather than neuromuscular performance. Practitioner Summary:Minor delays or mistakes can separate life and death at sea. The safety and productivity of most vessels rely on error-free performance of motor tasks. This study demonstrates that human ability to perform motor tasks is compromised by ship motions and may aid in developing training and safety guidelines for seafarers. [ABSTRACT FROM AUTHOR]

This paper demonstrates how specific surveillance technologies adopted in Canada during the Second World War enabled state actors to successfully conscript individuals into the Armed Forces. In 1940 the Federal government initiated a National Registration of all those under the age of sixteen living within the Dominion. Soon after, collected data were processed and certain populations were identified to be called into the Armed Forces. Although conscription had officially begun in 1940, a reorganization of the National Registration and mobilization system initiated in 1942 brought a new array of statistics-focused surveillance technologies into the procedure of selecting, calling men into service, and ensuring compliance with issued mobilization orders. These changes led to significant increases in the number of men that were successfully conscripted per month, pointing to the capacity of these new policies and technologies to assert greater statistical oversight and management over system staff as well as its target populations. This paper argues that the observable change in the effectiveness of the National Registration and mobilization system to conscript identified individuals into the Armed Forces came as a result of the new set of surveillance technologies adopted in March 1942. Specifically, these changes prompted a new means of statistical oversight and management, while they also worked to develop of a form of reactive path dependence in how data flowed within mobilization offices. [ABSTRACT FROM AUTHOR]

Environment Canada meteorological station hourly sampled air temperatures Tair at four stations in the southwest Yukon were used to identify cloud contamination in the Moderate Resolution Imaging Spectroradiometer (MODIS) Terra clear-sky daytime land surface temperature (LST) and emissivity daily level-3 global 1-km grid product (MOD11A1, Collection 5) that is not flagged by the MODIS quality algorithm as contaminated. The additional cloud masking used qualitative ground-based sky condition observations, collected at two of the four stations, and coincident MODIS quality flag information. The results indicate that air temperature observed at a variety of discrete spatial locations having different land cover is highly correlated with MODIS LST collected at 1-km grid spacing. Quadratic relationships between LST and air temperature, constrained by ground observations of 'clear' sky conditions, show less variability than relationships found under 'mainly clear' and 'mostly cloudy' sky conditions, and the more clouds observed in the sky coincides with a decreasing y intercept. Analysis of MODIS LST and its associated quality flags show a cold bias (<0°C) in the assignment of the ≤3-K-average LST error, indicating MODIS LST has a maximum average error of ≤2 K over a warm surface (>0°C). Analysis of two observation stations shows that unidentified clouds in MODIS LST are between 13% and 17%, a result that agrees well with previous studies. Analysis of daytime values is important because many processes are dependent on daylight and maximum temperature. The daytime clear-sky LST- Tair relationship observed for the good-quality confirmed cloud-free-sky MODIS LST quality flag can be used to discriminate cloud-contaminated grid cells beyond the standard MODIS cloud mask. [ABSTRACT FROM AUTHOR]

We address the challenging and economically important problem of seismic hazard estimation at low probabilities for stable cratonic regions such as central Canada which are characterized by very low seismicity rates. At low probabilities, large uncertainties in the seismicity rates result in calculated seismic hazards that are not negligible for practical purposes and may have significant implications for design and retrofit of critical structures such as hydroelectric and tailings dams. We examine the statistics of earthquake magnitude recurrence in such regions and their implications for hazard estimates at low probabilities. Recommendations for low-probability ground motions are provided that are related to the design life of the facilities. [ABSTRACT FROM AUTHOR]

The article looks at marine vessels called TEMPSC (totally enclosed motor propelled survival craft) which are used for industrial and commercial operation under extreme arctic environments. It notes observations however that shielding occupants inside the lifeboat from harsh external conditions produce adverse effects such as dangerous gas concentrations. Discussed are the authors' TEMPSC habitability studies on carbon dioxide accumulation through trials at-sea and on-land conducted in Canada.

Background: Needle exchange programs are effective public health interventions that reduce blood-borne infections, including hepatitis C, and injection-related infections. We sought to assess the return on investment of existing Prison Needle Exchange Programs (PNEPs) in Canadian federal prisons and their expansion to all 43 institutions., Methods: We developed a stochastic compartmental model that estimated hepatitis C and injection-related infections under different PNEP scenarios in Canadian federal prisons. Scenarios projected for 2018-2030 were no PNEP, status quo (actual PNEP implementation 2018-2022, with coverage maintained to 2030), and PNEP scale-up (coverage among people who inject drugs in prison increasing over 2025-2030 to reach 50% by 2030). We calculated the benefit-cost ratio as benefits from health care savings, divided by PNEP costs., Results: By 2019, PNEPs were implemented in 9 of 43 federal prisons, with uptake reaching 10% of people who injected drugs in prison in 2022. Compared with no PNEP, this was estimated to cost Can$0.45 (uncertainty interval [UI] $0.32 to $0.98) million and avert 37 (UI 25 to 52) hepatitis C and 8 (UI -1 to 16) injection-related infections over 2018-2030, with a benefit-cost ratio of 1.9 (UI 0.56-3.0). Compared with the status quo, the PNEP scale-up scenario cost an additional $2.7 (UI $1.8 to $7.0) million and prevented 224 (UI 218 to 231) hepatitis C and 77 (UI 74 to 80) injection-related infections, with a benefit-cost ratio of 2.0 (UI 0.57 to 3.3)., Interpretation: Every dollar invested in the current PNEP or its expansion is estimated to save $2 in hepatitis C and injection-related infection treatment costs. This return on investment strongly supports ongoing maintenance and scale-up of the PNEP in Canada from an economic perspective., Competing Interests: Competing interests:: Nadine Kronfli reports receiving research funding from the Canadian Institutes of Health and HIV/AIDS Research Initiative (grant numbers 190374 and 185725); Dr. Kronfli is also supported by a career award from the Fonds de Recherche Québec — Santé (FRQ-S; Junior 2). Mark Stoové reports receiving a Viiv Healthcare Medical Education Grant. No other competing interests were declared., (© 2024 CMA Impact Inc. or its licensors.)

The increase in dissolved organic carbon (DOC) concentrations in freshwater systems has received considerable attention due to its implications for drinking water treatment and numerous limnological processes. While past studies have documented the influence of recovery from acidification and climate change on long-term DOC trends, the emerging importance of these explanatory factors remains less understood. In addition, few studies have followed up on recent trends in sites that have undergone increases in DOC. Using a dataset from 1980 to 2020, we investigated interannual variations in DOC and dissolved organic nitrogen (DON) in 49 lakes across four eastern Canadian regions with a history of increases in DOC. We identified recent shifts in DOC patterns using LOESS smoothing and piecewise regression. We observed a stabilizing pattern or even a decrease (p < 0.001) in high acidification regions (Dorset and Nova Scotia), where increases in DOC were previously documented. At the low acid deposition region, IISD-Experimental Lakes Area, an increasing pattern in DOC stabilized in the early 2000s; however, DOC appears to be increasing again in recent years (p = 0.03). Our analysis identified precipitation and SO 4 deposition as the primary explanatory variables for DOC patterns (explaining 56-71% of variance). However, because acid deposition has declined substantially, climate and local watershed factors are becoming increasingly influential, leading to the emergence of new DOC patterns. Long-term changes in DOC and DON were not always synchronous, as these were often correlated with different factors (e.g., DON with ammonium deposition). This resulted in observable shifts in DOC:DON ratios, indicative of changes in dissolved organic matter (DOM) composition. We underscore the importance of ongoing monitoring in diverse regions because of the changing nature of environmental variables and new emerging trends., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Importance: The US and Canada currently have no formal published nationwide guidelines for specialists in poison information or emergency departments for the management of acetaminophen poisoning, resulting in significant variability in management., Objective: To develop consensus guidelines for the management of acetaminophen poisoning in the US and Canada., Evidence Review: Four clinical toxicology societies (America's Poison Centers, American Academy of Clinical Toxicology, American College of Medical Toxicology, and Canadian Association of Poison Control Centers) selected participants (n = 21). Led by a nonvoting chairperson using a modified Delphi method, the panel created a decision framework and determined the appropriate clinical management of a patient with acetaminophen poisoning. Unique to this effort was the collection of guidelines from most poison centers in addition to systematic collection and review of the medical literature. Comments from review by external organizations were incorporated before the guideline was finalized. The project began in March 2021 and ended in March 2023., Findings: The search retrieved 84 guidelines and 278 publications. The panel developed guidelines for emergency department management of single or repeated ingestion of acetaminophen. In addition, the panel addressed extended-release formulation, high-risk ingestion, coingestion of anticholinergics or opioids, age younger than 6 years, pregnancy, weight greater than 100 kg, and intravenous acetaminophen use. Differences from current US practice include defining acute ingestion as an ingestion presentation from 4 to 24 hours after overdose was initiated. A revised form of the Rumack-Matthew nomogram was developed. The term massive ingestion was replaced with the term high-risk ingestion and denoted by a specific nomogram line. Other recommendations include specific criteria for emergency department triage, laboratory evaluation and monitoring parameters, defining the role of gastrointestinal decontamination, detailed management of acetylcysteine treatment, associated adverse effects, and stopping criteria for acetylcysteine treatment, as well as criteria for consultation with a clinical toxicologist. Finally, specific treatment considerations, including acetylcysteine dosing, fomepizole administration, and considerations for extracorporeal elimination and transplant evaluation, were addressed., Conclusions and Relevance: This qualitative study provides a consensus statement on consistent evidence-based recommendations for medical, pharmacy, and nursing education and practice to optimize care of patients with acetaminophen poisoning.

Receptor-interacting protein kinase 1 (RIPK1), a regulator of inflammation and cell death, is a potential therapeutic target in immune-mediated inflammatory diseases (IMIDs). The objective of this phase IIa multicenter, randomized, double-blind, placebo-controlled study was to evaluate safety, tolerability pharmacokinetics, pharmacodynamics, and preliminary efficacy of GSK2982772, a RIPK1 inhibitor, in plaque-type psoriasis. Psoriasis patients (N = 65) were randomized to 60 mg twice daily (b.i.d.) or three times daily (t.i.d.), or placebo for 84 days. Most adverse events (AEs) were mild with no severe drug-related AEs reported. Plaque Lesion Severity Sum improved with b.i.d. treatment compared with placebo; interpretation of t.i.d. treatment results was complicated by a high placebo response. Reductions in epidermal thickness and infiltration by CD3+ T cells in the epidermis and dermis were observed compared with placebo. Results support the rationale for additional studies on RIPK1 inhibition in IMIDs., (© 2020 GlaxoSmithKline. Clinical Pharmacology & Therapeutics published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)

Background: About 40% of all health burden in New Zealand is due to cancer, cardiovascular disease, and type 2 diabetes/obesity. Outcomes for Māori (indigenous people) are significantly worse than non-Maori; these inequities mirror those found in indigenous communities elsewhere. Evidence-based interventions with established efficacy may not be effective in indigenous communities without addressing specific implementation challenges. We present an implementation framework for interventions to prevent and treat chronic conditions for Māori and other indigenous communities., Theoretical Framework: The He Pikinga Waiora Implementation Framework has indigenous self-determination at its core and consists of four elements: cultural-centeredness, community engagement, systems thinking, and integrated knowledge translation. All elements have conceptual fit with Kaupapa Māori aspirations (i.e., indigenous knowledge creation, theorizing, and methodology) and all have demonstrated evidence of positive implementation outcomes., Applying the Framework: A coding scheme derived from the Framework was applied to 13 studies of diabetes prevention in indigenous communities in Australia, Canada, New Zealand, and the United States from a systematic review. Cross-tabulations demonstrated that culture-centeredness (p = .008) and community engagement (p = .009) explained differences in diabetes outcomes and community engagement (p = .098) explained difference in blood pressure outcomes., Implications and Conclusions: The He Pikinga Waiora Implementation Framework appears to be well suited to advance implementation science for indigenous communities in general and Māori in particular. The framework has promise as a policy and planning tool to evaluate and design effective interventions for chronic disease prevention in indigenous communities.

Although many employees are using more information communication technology (ICT) as part of their jobs, few studies have examined the impact of ICT on their well-being, and there is a lack of validated measures designed to assess the ICT factors that may impact employee well-being. Therefore, we developed and validated a measure of ICT demands and supports. Using Exploratory Structural Equation Modeling, we found support for 8 ICT demands (i.e., availability, communication, ICT control, ICT hassles, employee monitoring, learning, response expectations, and workload) and two facets of ICT support (personal assistance and resources/upgrades support). Jointly, the ICT demands were associated with increased strain, stress, and burnout and were still associated with stress and strain after controlling for demographics, job variables, and job demands. The two types of ICT support were associated with lower stress, strain, and burnout. Resources/upgrades support moderated the relationship between learning expectations and most strain outcomes and between ICT hassles and strain. Personal assistance support moderated the relationship between ICT hassles and strain.