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Used two spatial and language tasks to investigate that clockwise directionality in circle drawing indicates neutral integration difficulties. Tasks were administered to 106 children, eight years of age. Data were analyzed for sex differences and circling behavior. None of the hypotheses based on Blau's theory was supported. (Author)

Mercury (Hg) is a toxic element which has increased in marine environments for more than a century, due largely to anthropogenic activities, and biomagnifies in food chains to harmful levels in some top predators like waterfowl and seabirds. We analysed total mercury (THg) concentrations in blood, brain and muscle tissue from healthy specimens of 13 coastal and pelagic bird species from eastern and northern Canada to provide a baseline on current concentrations, especially for brain concentrations which are highly underrepresented in the literature. We also examined within and among tissues relationships of THg concentrations within individuals. THg concentrations were generally higher in pelagic species and scavenging gulls, when compared to coastal waterfowl. Brain and muscle tissue had similar concentrations of THg in the birds examined, but both of these tissues had lower concentrations that those found in blood. Our results, and that of a previous study, suggest that body condition has a large influence on blood THg concentrations and should be considered when using blood as a sampling medium. Many of the species we examined had tissue THg above levels known to cause deleterious, sublethal effects in some species. [ABSTRACT FROM AUTHOR]

Soils are a source of elemental mercury (Hg(0)) to the atmosphere, however the effects of soil temperature and moisture on Hg(0) formation is not well defined. This research quantifies the effect of varying soil temperature (278–303 K), moisture (15–80% water filled pore space (WFPS)) and sterilization on the kinetics of Hg(0) formation in forested soils of Nova Scotia, Canada. Both, the logarithm of cumulative mass of Hg(0) formed in soils and the reduction rate constants ( k values) increased with temperature and moisture respectively. Sterilizing soils significantly ( p < 0.05, n = 10) decreased the percent of total Hg reduced to Hg(0). We describe the fundamentals of Hg(0) formation in soils and our results highlight two key processes: (i) a fast abiotic process that peaks at 45% WFPS and depletes a small pool of Hg(0) and; (ii) a slower, rate limiting biotic process that generates a large pool of reducible Hg(II). [ABSTRACT FROM AUTHOR]

Increases in the environmental awareness of global consumers coupled with pressure from regional stakeholders has forced forest managers to demonstrate the potential implications of forest management activities for a broad range of indicators. This paper describes the construction and application of a hierarchical decision-support system for evaluating multi-objective management options for a 288,000 ha forest in northeastern British Columbia. The decision-support system includes a stand-level model, a forest estate model, a habitat model and a visualization model. A set of criteria and indicators, developed in conjunction with a public advisory committee, were used to identify key economic, ecological and social objectives. Indicators include volume harvested, gross profit, active road density, ecosystem carbon storage, age-class distribution, patch-size distribution, snag density, visual aesthetics and backcountry recreation area. A natural disturbance baseline and two alternative harvest strategies that include natural disturbance are projected and assessed with the decision-support system. The first strategy represents a dispersed harvesting approach in which cut blocks are limited to sizes <60 ha. The second strategy represents an aggregated harvesting approach in which a range of cut block sizes (up to 2000 ha) and shapes is created that more closely follows the distribution of openings generated from natural disturbance events in the region. Spatial and temporal changes in each indicator are presented and evaluated for the harvest strategies, and compared to the natural disturbance baseline where appropriate. The application of the decision-support system for strategic analysis of management options is discussed, including a review of the importance of representing the impacts of natural disturbance and the benefits and risks associated with the use of visualization techniques for presenting results to stake holder groups. [Copyright &y& Elsevier]

Investigates the influence of bedrock lithology on methylmercury (MeHg) concentrations in wetlands of Kejimkujik National Park, Nova Scotia, Canada. Role of wetlands in the export of MeHg to the watershed; Determination of the chemistry of the surface water; Type of lithology present in the terrestrial landscape.

Diurnal patterns for dissolved gaseous mercury (DGM) concentration, mercury flux, several water variables (pH, oxidation reduction potential (ORP), water temperature), and meteorological variables (wind speed, air temperature, % relative humidity, solar radiation) were measured in two lakes with contrasting dissolved organic carbon (DOC) concentrations in Kejimkujik Park, Nova Scotia. A continuous analysis system made it possible to measure quick changes in DGM over time. Consistently higher DGM concentrations were found in the high DOC lake as compared to the low DOC lake. An examination of current mercury flux models using this quantitative data indicated some good correlations between the data and predicted flux (r ranging from 0.27 to 0.83) but generally poor fit (standard deviation of residuals ranging from 0.97 to 3.38). Crosscorrelation analysis indicated that DGM dynamics changed in response to solar radiation with lag-times of 65 and 90 min. This relationship with solar radiation was used to develop new predictive models of DGM and mercury flux dynamics for each lake. We suggest that a generalized approach using time-shifted solar radiation data to predict DGM can be incorporated into existing mercury flux models. It is clear from the work presented that DOC and wind speed may also play important roles in DGM and mercury flux dynamics, and these roles have not been adequately accounted for in current predictive models. [ABSTRACT FROM AUTHOR]

Examines the importance of microbial mercury oxidation and reduction in regulating dissolved gaseous mercury patterns in freshwater lakes in Ontario. Calculation of the evasion rate of elemental mercury; Induction o microbial mercury oxidase and reductase activity; Role of sunlight on the transformations of divalent nad elemental mercury.

The Leach's storm-petrel (Hydrobates leucorhous) is one of the most abundant and widely distributed marine birds in the North Atlantic but is under global population decline, possibly linked to marine pollution. We determined levels of ingested plastic and hepatic total mercury (THg) in recently fledged juveniles that stranded in Newfoundland and Labrador, Canada, and assessed the relationship to body condition, size and diet. Plastic prevalence was high (87.5%) but hepatic THg was relatively low (mean 486.7 ng/g dry weight) compared to other studies. Levels of neither pollutant were significantly related to body metrics of health. Our data confirm that plastic and mercury are pervasive in the western North Atlantic Ocean, prominent even in young birds. • A mass stranding event allowed recently fledged Leach's storm-petrels to be sampled. • 87.5% of recently fledged birds contained plastic pollution. • Average hepatic THg (mean 486.7 ng/g) was lower than adults. • Plastic pollution and mercury pollution were not significantly correlated with bird body condition. [ABSTRACT FROM AUTHOR]

In this study, we assessed the suitability of using a standard reference material (SRM) other than National Institute of Standards and Technology (NIST) 2710a or NIST 2711a in USEPA Method 1340 to determine arsenic (As) and lead (Pb) in vitro bioaccessibility (IVBA) and the capabilities of Canadian-based laboratories to perform the method. Five laboratories participated in an initial round robin study and analyzed NIST 2710a, NIST 2711a, BGS119, and Enviromat SS-2. Intra- and inter-laboratory variability were generally acceptable with percentage relative standard deviations (RSD) of less than 20%. The mean total As and Pb concentrations obtained for BGS119 (332 and 936 mg/kg, respectively) and the mean IVBA values (As = 14.3% and Pb = 78.1%) suggested it may be a suitable and acceptable SRM, whereas the concentration of As in Enviromat SS-2 as received (3.2 mg/kg) was deemed too low. Ten soil samples from sites with varying land use were analyzed in a follow-up round robin study using the modified IVBA method that included BGS119 as SRM. The concentrations of As and Pb in the IVBA extracts reported by the participating laboratories were comparable. The mean As IVBA values for the field-collected samples ranged from 0.1% to 56.4%; for Pb, they ranged from 7.0% to 121%. The lowest IVBA values were measured in mine site samples; the highest values were associated with smelter-affected soils. The low IVBA values correlated with high iron content. Intra- and interlaboratory reproducibility were acceptable (RSD < 30%). Based on the findings of the study, laboratories can use the modified method to provide reproducible and comparable As and Pb IVBA data. The use of BGS119 as an alternative SRM to assess contaminated sites in the province of British Columbia for regulatory purposes is recommended, as it is representative of As and Pb concentrations in contaminated soils in British Columbia. Integr Environ Assess Manag 2024;20:1486-1495. © 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC)., (© 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).)

Studies on mercury bioaccumulation and biomagnification in coastal invertebrates in eastern Canada are limited, but these data are necessary to determine risk of mercury exposure effects in upper trophic level organisms. We quantified methylmercury (MeHg), total mercury (THg), and stable isotopes of δ 13 C and δ 15 N in 14 species of invertebrates in the Minas Basin. The overall mean concentration of MeHg (12.78 ± 11.23 ng/g dw) was approximately 10 times below the Canadian guideline for the protection of wildlife consumers like fish and birds of 157.20 ng/g dry weight (dw). Invertebrates at higher trophic positions (δ 15 N) had greater THg and particularly MeHg. The Trophic Magnification Factors (TMF) for MeHg and THg (1.59 and 1.21 respectively) were similar to others reported in studies of food webs containing higher trophic level organisms., 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 © 2023 Elsevier Ltd. All rights reserved.)

Seabirds are important biovectors of contaminants, like mercury, moving them from marine to terrestrial environments around breeding colonies. This transfer of materials can have marked impacts on receiving environments and biota. Less is known about biotransport of contaminants by generalist seabirds that exploit anthropogenic wastes compared to other seabird species. In this study, we measured total mercury (THg) in O-horizon soils at four herring gull (Larus smithsoniansus) breeding colonies in southern Nova Scotia, Canada. At colonies with dry substrate, THg was significantly higher in soils collected from gull colonies compared to nearby reference soils with no nesting gulls. Further, THg was distinct in soils among study colonies and was likely influenced by biotransport from other nesting seabird species, most notably Leach's storm-petrels (Hydrobates leucorhous). Our research suggests gulls that scavenge on anthropogenic wastes at local industrial sites are biovectors moving THg acquired at these sites to their colonies and may increase the spatial footprint of contaminants from these industries., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

As the world's population ages, a question of who can be trusted to look after the increasing elderly population arises. Health care professionals are commonly considered one of the group of people we entrust with our health care and maintenance of a good quality of life. Unfortunately, some abuse this trust. Harold Shipman, Elizabeth Wettlaufer and Roger Dean are three examples of health care professionals held responsible for multiple homicides of patients aged 65 years and older in their care. Harold Shipman, a United Kingdom doctor, is suspected of killing potentially 400 patients over 27 years. However, the true number may never be known. Elizabeth Wettlaufer, a Canadian nurse, admitted to killing eight patients over seven years and Roger Dean, an Australian nurse, killed 11 patients in one night by deliberately lighting a fire in a health care facility. The subsequent inquiry reports into their actions resulted in multiple recommendations which aimed to prevent similar occurrences and to protect the lives of this vulnerable cohort of people. These recommendations included restrictions on the hiring process of health care professionals and increasing the accountability of access to Schedule Eight drugs by doctors and registered nurses. The governments responsible for responding to the inquiry reports have done so in various ways, although not all recommendations have been implemented and some may not be practical with current residential care infrastructure provisions and requirements. More work is required to determine the types of countermeasures that could be implemented to protect the elderly from maverick health care professionals., Competing Interests: None.

Background: Blended learning, which integrates face-to-face and online instruction, is increasingly being adopted. A gap remains in the literature related to blended learning, self-efficacy, knowledge and perceptions in undergraduate nursing., Objectives: To investigate outcomes of self-efficacy, knowledge and perceptions related to the implementation of a newly blended course., Design: This was a quasi-experimental pre-post test design., Setting: This study was conducted at an undergraduate university in Alberta, Canada., Participants: A total of 217 second-year undergraduate nursing students participated and 187 participants completed all study components., Methods: A convenience sampling method was used. Data were collected at the start and end of the semesters. Data were analyzed using descriptive and inferential statistics using R(3.4.3) and R-Studio(1.1.423)., Results: There were no significant differences in self-efficacy scores between groups or in the pre-post surveys (p > 0.100) over time. There was no significant difference in knowledge between the blended online and face-to-face groups (p > 0.100). For students in the blended course, perceptions of the online learning environment were positive., Conclusion: Blended learning has the potential to foster innovative and flexible learning opportunities. This study supports continued use and evaluation of blended learning as a pedagogical approach., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Aim: Demands for mental health services in post-secondary institutions are increasing. This paper describes key features of a response to these needs: ACCESS Open Minds University of Alberta (ACCESS OM UA) is focused on improving mental health services for first-year students, as youth transition to university and adulthood., Methods: The core transformation activities at ACCESS OM UA are described, including early case identification, rapid access, appropriate and timely connections to follow-up care and engagement of students and families/carers. In addition, we depict local experiences of transforming existing services around these objectives., Results: The ACCESS OM UA Network has brought together staff with diverse backgrounds in order to address the unique needs of students. Together with the addition of ACCESS Clinicians these elements represent a systematic effort to support not just mental health, but the student as a whole. Key learnings include the importance of community mapping to developing networks and partnerships, and engaging stakeholders from design through to implementation for transformation to be sustainable., Conclusions: Service transformation grounded in principles of community-based research allows for incorporation of local knowledge, expertise and opportunities. This approach requires ample time to consult, develop rapport between staff and stakeholders across diverse units and develop processes in keeping with local opportunities and constraints. Ongoing efforts will continue to monitor changing student needs and to evaluate and adapt the transformations outlined in this paper to reflect those needs., (© 2019 The Authors Early Intervention in Psychiatry Published by John Wiley & Sons Australia, Ltd.)

Aim: Youth mental health is of paramount significance to society globally. Given early onset of mental disorders and the inadequate access to appropriate services, a meaningful service transformation, based on globally recognized principles, is necessary. The aim of this paper is to describe a national Canadian project designed to achieve transformation of mental health services and to evaluate the impact of such transformation on individual and system related outcomes., Method: We describe a model for transformation of services for youth with mental health and substance abuse problems across 14 geographically, linguistically and culturally diverse sites, including large and small urban, rural, First Nations and Inuit communities as well as homeless youth and a post-secondary educational setting. The principles guiding service transformation and objectives are identical across all sites but the method to achieve them varies depending on prevailing resources, culture, geography and the population to be served and how each community can best utilize the extra resources for transformation., Results: Each site is engaged in community mapping of services followed by training, active stakeholder engagement with youth and families, early case identification initiatives, providing rapid access (within 72 hours) to an assessment of the presenting problems, facilitating connection to an appropriate service within 30 days (if required) with no transition based on age within the 11 to 25 age group and a structured evaluation to track outcomes over the period of the study., Conclusions: Service transformation that is likely to achieve substantial change involves very detailed and carefully orchestrated processes guided by a set of values, principles, clear objectives, training and evaluation. The evidence gathered from this project can form the basis for scaling up youth mental health services in Canada across a variety of environments., (© 2018 The Authors Early Intervention in Psychiatry Published by John Wiley & Sons Australia, Ltd.)

In temperate regions of Canada, mercury (Hg) concentrations in biota and the magnitude of Hg biomagnification through food webs vary between neighboring lakes and are related to water chemistry variables and physical lake features. However, few studies have examined factors affecting the variable Hg concentrations in landlocked Arctic char (Salvelinus alpinus) or the biomagnification of Hg through their food webs. We estimated the food web structure of six high Arctic lakes near Resolute Bay, Nunavut, Canada, using stable carbon (δ(13)C) and nitrogen (δ(15)N) isotopes and measured Hg (total Hg (THg) in char, the only fish species, and methylmercury (MeHg) in chironomids and zooplankton) concentrations in biota collected in 2010 and 2011. Across lakes, δ(13)C showed that benthic carbon (chironomids) was the dominant food source for char. Regression models of log Hg versus δ(15)N (of char and benthic invertebrates) showed positive and significant slopes, indicting Hg biomagnification in all lakes, and higher slopes in some lakes than others. However, no principal components (PC) generated using all water chemistry data and physical characteristics of the lakes predicted the different slopes. The PC dominated by aqueous ions was a negative predictor of MeHg concentrations in chironomids, suggesting that water chemistry affects Hg bioavailability and MeHg concentrations in these lower-trophic-level organisms. Furthermore, regression intercepts were predicted by the PCs dominated by catchment area, aqueous ions, and MeHg. Weaker relationships were also found between THg in small char or MeHg in pelagic invertebrates and the PCs dominated by catchment area, and aqueous nitrate and MeHg. Results from these high Arctic lakes suggest that Hg biomagnification differs between systems and that their physical and chemical characteristics affect Hg concentrations in lower-trophic-level biota., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Dragonflies (Odonata: Anisoptera) are an important component of both aquatic and terrestrial food webs and are vectors for methylmercury (MeHg) biomagnification. Variations in mercury content with life stage and body regions may affect the relative transfer of mercury to aquatic or terrestrial food webs; however, there has been little research on this subject. Also, little is known about mercury bioaccumulation in different body regions of dragonflies. To address these knowledge gaps, dragonfly naiads, adults, and exuviae were collected at 2 lakes in Kejimkujik National Park, Nova Scotia, Canada, and mercury concentrations in different life stages and body regions were quantified. Mean whole body concentrations of MeHg were substantial in naiads (232 ± 112 ng g(-1) dry wt, n = 66), emerging adults (236 ± 50 ng g(-1) dry wt, n = 10), and mature adults (231 ± 74 ng g(-1) dry wt, n = 20). Mean MeHg concentrations in exuviae (5.6 ± 4.3 ng g(-1), n = 32) were 40-fold lower than in naiads and adults. Emerging adults had 2-fold to 2.5-fold higher Hg(II) concentrations than naiads, mature adults, and exuviae. In body regions of both naiads and adults, some abdomens contained significantly higher concentrations of Hg(II) than heads or thoraces, and this trend was consistent across families. Across families, Aeshnidae had significantly higher concentrations of MeHg and total Hg than Gomphidae and Libellulidae, but not higher than Cordulidae. The Hg(II) concentrations were lower in Aeshnidae and Libellulidae than in Gomphidae and Cordulidae. Shedding of exuviae presents a possible mechanism for mercury detoxification, but mercury concentrations and burdens in exuviae are low in comparison with naiads and adults. Dragonfly adults retain a high potential for transferring substantial amounts of MeHg to their predators., (© 2014 SETAC.)

Methylmercury [MeHg(I) in the aerobic surface water of lakes is thought to be rapidly degraded, but contrary to expectations, we show that MeHg(I) concentrations often increase during sunlight hours or remain relatively constant. We hypothesized that there were water column processes that generated MeHg(I) and that these processes were linked to dissolved organic matter (DOM) and solar radiation. A 2-day diurnal pattern of MeHg(I) in surface water with corresponding bottled controls was assessed for two contrasting lakes in Kejimikujik, Nova Scotia, Canada. Following this study, a tangential ultrafiltrator was used to size-fractionate and generate a concentration gradient of DOM from four different lakes located near Lac Berthelot, Quebec, Canada. The watersheds of two of these lakes were not substantially logged whereas the other two had been extensively logged. Different size fractions of DOM as well as different concentrations of DOM were exposed to sunlight for varying periods of time. We observed that, in Keiimikujik, the concentration of MeHg(I) in surface waters peaked in the early afternoon. Furthermore, this also occurred in bottled water for one of the lakes, Puzzle, eliminating the possibility that in-lake mixing played a role in this pattern. The formation of MeHg(I) was found to be dependent on the size fraction and amount of DOM present in the water. Specifically, DOM less than 5 kDa or between 30 and 300 kDa generated MeHg(I) when exposed to sunlight, but larger fractions did not. Furthermore, although data are limited, we found that water from lakes with logged watersheds generated MeHg(I) when exposed to sunlight, whereas water from lakes with low levels of logging in the undisturbed watersheds did not. Our results demonstrate that MeHg(I) can be formed in freshwaters of certain lakes in response to solar radiation. This photoproduction of MeHg(I) is dependent on DOM concentrations and type, with the importance of water chemistry not yet clear. The significance of this process to freshwater lakes and the mechanism responsible for MeHg(I) photoproduction is still unclear, but a correction in the conventional wisdom that MeHg(I) is rapidly photodegraded is timely.

Objective: The purpose of this study was to determine the extent to which data entry forms, guidelines, and other materials used for documentation in intensive care units (ICUs) attend to 6 key end-of-life care (EOLC) domains: 1) patient and family-centered decision making, 2) communication, 3) continuity of care, 4) emotional and practical support, 5) symptom management and comfort care, and 6) spiritual support. A second purpose was to determine how these materials might be modified to include more EOLC content and used to trigger clinical behaviors that might improve the quality of EOLC., Participants: Fifteen adult ICUs-8 medical, 2 surgical, and 4 mixed ICUs from the United States, and 1 mixed ICU in Canada, all affiliated with the Critical Care End-of-Life Peer Workgroup, Methods: Physician-nurse teams in each ICU received detailed checklists to facilitate and standardize collection of requested documentation materials. Content analysis was performed on the collected documents, aimed at characterizing the types of materials in use and the extent to which EOLC content was incorporated., Measurements and Main Results: The domain of symptom management and comfort care was integrated most consistently on forms and other materials across the 15 ICUs, particularly pain assessment and management. The 5 other EOLC domains of patient and family centered decision-making, communication, emotional and practical support, continuity of care, and spiritual support were not well-represented on documentation. None of the 15 ICUs supplied a comprehensive EOLC policy or EOLC critical pathway that outlined an overall, interdisciplinary, sequenced approach for the care of dying patients and their families. Nursing materials included more cues for attending to EOLC domains and were more consistently preprinted and computerized than materials used by physicians. Computerized forms concerning EOLC were uncommon. Across the 15 ICUs, there were opportunities to make EOLC- related materials more capable of triggering and documenting specific EOLC clinical behaviors., Conclusions: Inclusion of EOLC items on ICU formatted data entry forms and other materials capable of triggering and documenting clinician behaviors is limited, particularly for physicians. Standardized scales, protocols, and guidelines exist for many of the EOLC domains and should be evaluated for possible use in ICUs. Whether such materials can improve EOLC has yet to be determined.