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Prior research suggests that parents of Hispanics, English learners, and students living in poverty exercise school choice less frequently than other parents, which may be a factor in the resegregation of public schools. This quasi-experimental, causal-comparative design tests whether ethnicity, language dominance, or socioeconomic status of the student are related to the exercise of parental choice of magnet middle school programs in a majority, minority community. The primary finding was that in this Hispanic, English learner, low-income majority California community, none of the independent variables studied predicted the exercise of parental magnet school choice. The discussion compares these findings with prior studies and suggests some possible explanations.

Can Indigenous truth commissions overcome the legacies and contemporary effects of colonialism? A study on the Australian-Canadian experience to explore possible paths in Argentina: While restorative justice has been extensively growing in democratic settings, less explored is its connection with transitional justice or, in other words, there have been insufficient attempts to explore the possibility of applying restorative justice mechanisms in countries dealing with the aftermath of mass violence. Seeking to fill this gap, this article addresses the connections between transitional justice and Indigenous demands. Particularly, the study focuses on the role of truth commissions as a restorative justice mechanism with the potential of creating a new narrative on human rights violations (or a 'narrative turn'). The article then analyses the experience of Indigenous truth commissions in Australia and Canada, considering them within their political contexts and providing a critical analysis of the results. Finally, the study analyses the Argentinean case and the possibility for a truth commission to uncover the legacy of human rights violations against Indigenous communities. It also considers how the comparative experience assists in assessing the pertinence of having a truth commission in Argentina. Altogether, the article aims to explore the role of truth commissions, applied through a decolonial, transformative and actor-centred perspective, and their potential to challenge the narratives that have largely legitimised or denied harms against Indigenous peoples. [ABSTRACT FROM AUTHOR]

The number of science and discovery centres has grown exponentially over the last two centuries. Science and discovery centres are one of the top five stimuli that influence a career choice in science. Their history, growth, impact and role in the public understanding of science are discussed. (Contains 2 tables, 7 figures, and 21 online resources.)

Objective: The 2019 Canadian guideline for physical activity throughout pregnancy provides evidence-based recommendations to promote maternal, fetal, and neonatal health. We aimed to 1) critically appraise the 2019 Canadian guideline for physical activity throughout pregnancy; and 2) develop a guideline summary for clinicians to facilitate the uptake of recommendations into practice. Methods: We used the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument to critically appraise the quality and reporting of this guideline. Four reviewers independently scored between 1 (strongly disagree) to 7 (strongly agree) for 23 items organized into six quality domains. Results; AGREE II quality domain scores ranged from 47%-64% and the overall quality of the guideline was rated as 83% (high quality). Conclusion: Based on its methodological quality, we recommend the use of this guideline. Our guideline summary includes six recommendations and other safety precautions that are relevant for clinicians in Canada. [ABSTRACT FROM AUTHOR]

The growing crisis of bee health has shone a spotlight on the problems facing pollinator populations in many parts of the world, the worrying implications for agriculture and ecosystems, and some of the risks of pesticides. Although this attention is important and can open a range of critical vistas, the threats to bees, other pollinators, and the future of pollination are too often framed in narrow ways. The goal of this paper is to provide a systematic way of thinking about the crisis of bee populations by examining the changing dynamics of pollination within industrial agriculture, drawing heavily on transformations in the United States and Canada. We set out a case for understanding pollination as a biophysical barrier to industrial organization and the rise of pollination services as a response that temporarily fixes (or overrides) this barrier, while containing an internal set of contradictions and overrides. We argue that these dialectic relations are continually generating further problems and hope that this lens can help inform critical education, outreach, and movement building with respect to the urgent problems of bee and pollinator health. In particular, we stress the need to connect growing bee‐related advocacy with struggles to confront industrial capitalist agriculture. [ABSTRACT FROM AUTHOR]

Assessing metal distributions in cities is an important aspect of urban environmental quality management. Western honeybees (Apis mellifera) and their products are biomonitors that can elucidate small‐scale metal distribution within a city. We compare range and variations in trace element (TE) concentrations and lead (Pb) isotopic compositions of honey, bee tissue, bee pollen, and propolis collected throughout Metro Vancouver (BC, Canada). Honey, bee, and bee pollen results have similar TE and isotopic trends; samples collected in urban and industrialized areas exhibit elevated concentrations of anthropogenically influenced TE (e.g., Pb, Zn, V, and Ti) and a less radiogenic Pb isotopic composition (i.e., lower 206Pb/207Pb and elevated 208Pb/206Pb) relative to their suburban and rural counterparts. For example, 206Pb/207Pb, 208Pb/206Pb in honey range from 1.126, 2.131 and 1.184, 2.063; extremes measured in honey from urban and suburban/rural areas, respectively. Except for propolis, measured and interpolated (kriged) results in all materials reflect the immediate zoning or land use setting near the hive, providing kilometer‐scale geospatial resolution, suitable for monitoring urban systems. Statistical analysis reveals that no systematic variations or intra‐ or inter‐annual trends exist in TE concentrations or Pb isotopic compositions, including among sampling and field methods (i.e., old vs. new hive equipment and honey from the brood nest box vs. honey super). The results of this systematic study using honeybees and hive products in Metro Vancouver provide a robust, current baseline for future comparison of local land use and environmental policy change. Key Points: Honeybees and their products can help monitor metal distributions in urban environmentsPb isotopes and trace element concentrations in hive matrices are geospatially and temporally reproducible over several yearsTypical hive management practices (reusing equipment or splitting hives) do not hinder biomonitoring utility of hive products [ABSTRACT FROM AUTHOR]

Urbanization alters the landscape, degrades and fragments habitats, and can have a profound effect on species interactions. Plant–pollinator networks may be particularly sensitive to urbanization, because plants and their insect pollinators have been shown to respond to urbanization both positively and negatively. To better understand the relationship between urbanization, pollinator behavior, and season on pollinator-mediated plant reproduction, we created 30 experimental plant populations along an urbanization gradient in the Greater Toronto Area, Canada. To test how urbanization affects plant reproduction and between-patch pollen dispersal, we created a standard hermaphroditic plant patch at each site, and a male-sterile plant patch at a subset of sites. We measured plant reproduction in the early and late summer in each of 2 years. Plants in urban sites produced significantly fewer flowers than plants in the nonurban sites, whereas seed number per plant either increased or decreased with urbanization, depending on the season. Experimental populations in urban sites also exhibited reduced pollen dispersal between patches. Pollen dispersal between patches was greatest early in the summer and declined with increased impervious surface and proximity to the city. Together, our results are likely caused by variation in environmental conditions and pollinator services across the urban gradient, resulting in pollen limitation and pollen dispersal differences among sites. Our work adds to the small but growing body of literature on urban plant-pollinator interactions and suggests that responses to urbanization are context-dependent. [ABSTRACT FROM AUTHOR]

The parent magma and mantle source of the Mesoproterozoic Kiglapait intrusion, the largest and youngest troctolitic intrusion in the Nain Plutonic Suite of coastal Labrador, Canada, are evaluated using an integrated Pb–Sr–Nd–Hf isotopic and trace element framework. The bowl-shaped Kiglapait intrusion crystallized mostly as a closed system, forming an 8 km-thick stack of differentiated cumulates from the troctolitic Lower Zone (0–84% solidified or PCS) through the olivine gabbroic to ferrosyenitic Upper Zone (84–100 PCS). Whole-rocks and mineral separates (plagioclase, clinopyroxene, bulk mafic minerals) were analysed from eight different stratigraphic locations from 5 to 89·3 PCS. This new dataset is complemented by Pb–Sr–Nd TIMS isotopic analyses of samples spanning the entire magmatic stratigraphy of the Kiglapait intrusion (29 samples, 0·12 to 99·99 PCS) and from the Nain Plutonic Suite (26 samples) for regional comparisons. There is no significant change in initial Nd and Hf isotopic ratios from the base to the top of the intrusion. In contrast, initial 87Sr/86Sr steadily increases in the Upper Zone due to progressively increasing small amounts of assimilation of country rock with a composition similar to local Proterozoic supracrustal rocks and Archean gneiss. The Pb isotopic analyses, both MC-ICP-MS and TIMS, reveal differences between less radiogenic plagioclase and more radiogenic mafic separates in nearly all samples. This feature is attributed to cryptic alteration from interaction with a high-temperature, externally-derived, hydrothermal fluid in oxygen isotope equilibrium with the host anorthositic rocks. The Pb isotope composition of the Kiglapait parent magma was recovered through systematic analysis of leached plagioclase separates (and corresponding leachate solutions). Trace element modeling combined with Pb–Sr–Nd–Hf isotopic constraints indicate that the Kiglapait parent magma was derived from depleted mantle (∼95%) with a small contribution (∼5%) from the lower crust assimilated during ponding at the Moho or during transit through the crust. This geochemical model is extended to the origin of other troctolitic and anorthositic magmas in the Nain Plutonic Suite at a regional scale. Most of the Pb–Sr–Nd isotopic compositions of the Nain anorthosites are compatible with crystallization from melts that originated from the mantle and that assimilated variable extents of crustally-derived melts (3–30%). The multi-isotopic and trace element geochemical framework developed for the Kiglapait intrusion in this study can be applied to the investigation of the source, parent magma, differentiation processes and post-crystallization changes in layered intrusions and anorthosites throughout the geological record. [ABSTRACT FROM AUTHOR]

We assessed the attitudes of Canadian obstetricians toward chiropractic with a 38-item cross-sectional survey. Ninety-one obstetricians completed the survey, for a response rate of 14% (91 of 659). Overall, 30% of respondents held positive views toward chiropractic, 37% were neutral, and 33% reported negative views. Most (77%) reported that chiropractic care was effective for some musculoskeletal complaints, but 74% disagreed that chiropractic had a role in treatment of non-musculoskeletal conditions. Forty percent of respondents referred at least some patients for chiropractic care each year, and 56% were interested in learning more about chiropractic care. Written comments from respondents revealed concerns regarding safety of spinal manipulation and variability among chiropractors. Canadian obstetricians’ attitudes toward chiropractic are diverse and referrals to chiropractic care for their patients who suffer from pregnancy-related low back pain are limited. Improved interprofessional relations may help optimize care of pregnant patients suffering from low back pain. [ABSTRACT FROM AUTHOR]

This paper describes the development of a data set mapping all commercial wind turbines in Canada: the 9th largest onshore wind energy fleet in the world. Details contained in the data enable the analysis of the evolution of commercially deployed wind turbines as well as the illustrating the effects of the introduction and cessation of different policies affected historical deployment. In total, over 6700 turbines spanning more than 265 projects and nearly 14.0 GW of generating capacity were indexed including coordinates, model, manufacturer, owner, tower height and commissioning date. Data were compiled from publicly available sources including planning documents, technical reports, environmental impact studies and acoustic emission reports. In 2021, average rotor diameters were 140 m with 108 m tall towers, more than triple the average diameter and double the average tower height from 20 years ago. The analysis of this data found that a typical wind farm in Canada consists of 0.97 turbines/km 2 , while the typical installed capacity density has recently jumped from around 1 to 2.94 MW/km 2 in 2021. Competitive procurement policies have often trended towards larger installed capacities, whereas smaller wind farms emerged more often when policies directed at community ownership were in place. Policies that encouraged local manufacturing developed regional clusters of particular manufacturers, but generally ceased after the local manufacturing policies ended. This work serves as a benchmark for the evolution of wind energy in Canada and a framework for similar data sets in other jurisdictions, and provides a resource for academic researchers, wind farm developers, government bodies and planning agencies as well as the general public. • Details of the Canadian wind fleet database mapping over 6700 individual turbines. • Discussion of the major policies that have influenced the evolution of wind in Canada. • Evolution of wind turbine and wind farm size and capacity density. [ABSTRACT FROM AUTHOR]

Recent evidence suggests that the Cougar (Puma concolor) has returned to New Brunswick, Quebec, Manitoba, and Ontario. An abundance of sightings have been reported for many decades throughout south-central Ontario, but genetic confirmation has been confounded by a lack of carcasses or DNA. In this paper, we identify (1) genetic evidence of a single Cougar in the wild of Ontario, (2) a gene (cytochrome b) and methodology to distinguish the Cougar from other mammals in Ontario using scats, hair follicles, and soft and hard tissue, and (3) a gene that can distinguish individual Cougars from each other and would distinguish populations of subspecies if they exist in Ontario. Potential Cougar scats and other tissue samples were collected from across Ontario, and hair snares baited with catnip and carnivore lure were placed in locations where Cougar sightings were frequent, near Sudbury, Ontario. We analyzed samples for mtDNA, and one scat sample from the Wainfleet Bog Conservation Area, Port Colborne, Ontario, was positive for Cougar. Evidence from archeological data and Cougar sightings suggests that the historical range of Cougars extended in Ontario from the Great Lakes-St. Lawrence Ecotone south, primarily associated with the Eastern Deciduous Forest Biome and the primary prey of the Cougar, the White-tailed Deer (Odocoileus virginianus) and the North American Elk (Cervus elaphus). The data suggest that Cougar distribution has moved north in recent times due to clear-cutting, along with their primary prey. Further studies of Cougar presence in the province are warranted. [ABSTRACT FROM AUTHOR]

Abstract: Environmental monitoring and remediation require techniques to identify the source and fate of metals emissions. The measurement of heavy metal isotopic signatures, made possible by the advent of the MC-ICP-MS, is a powerful new geochemical tool, which may be used to trace the source of these metals in the environment. In a multi-tracer study, Cd, Zn and Pb isotopic compositions (MC-ICP-MS) and elemental concentrations (HR-ICP-MS) are used to distinguish between natural and anthropogenic sources of these metals in bivalves collected from western Canada (British Columbia), Hawaii, and the USA East Coast. Variability in the δ114/110Cd values of bivalves (−1.20‰ to −0.09‰) is attributed to differences in the relative contributions of Cd from natural and anthropogenic sources between sites. Cadmium isotopic compositions (δ114/110Cd=−0.69‰ to −0.09‰) identify high Cd levels in B.C. oysters as primarily natural (i.e., upwelling of Cd rich intermediate waters in the North Pacific), with some variability attributed to anthropogenic sources (e.g., mining and smelting). Variability in the δ66/64Zn values exhibited by the B.C. bivalves is relatively small (0.28–0.36‰). Despite the low Pb levels found in B.C. oysters, Pb isotopes are used to identify emissions from industrial processes and the consumption of unleaded gasoline and diesel fuel as significant metal sources. Although the Cd concentrations of the USA East Coast bivalves are primarily lower than those of B.C. oysters, their relatively light Cd isotopic compositions (δ114/110Cd=−1.20‰ to −0.54‰) indicate the significance of anthropogenic Cd sources and are attributed to the high prevalence of industry on this coast. The δ114/110Cd values of USA East Coast bivalves include the lightest ever reported, with the exception of values reported for extraterrestrial materials. In addition, the Pb isotopic compositions of bivalves from the USA East Coast indicate Pb emissions from the combustion of coal are an important source of Pb, consistent with the high consumption of coal for power production on this coast. This study demonstrates the effective use of Cd and Zn isotopes to trace anthropogenic sources in the environment and the benefit of combining these tools with Pb “fingerprinting” techniques. [Copyright &y& Elsevier]

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The tissue mercury concentrations in six species of fish collected at the 17 Areas of Concern identified by the International Joint Commission on the Canadian side of the Great Lakes were analyzed using an Environment Canada database. A linear increase in mercury concentration with fish length was found, but slopes differed among locations. The temporal pattern over the period 1971–1997 differed across species in fish collected in Lake St. Clair; in at least two species there was evidence of increased mercury concentration during the 1990s that had been suggested in an earlier analysis. Areas of Concern differed significantly in observed tissue concentrations. Differences observed did not consistently parallel expectations associated with the historical presence of chlor-alkali plants in the vicinities of some locations. An attempt to correlate the fish tissue mercury concentration with the frequency of occurrence of infantile cerebral palsy at Areas of Concern was unsuccessful. [Copyright &y& Elsevier]

The contemporary academic environment in Canada has undergone reorganization based on neoliberal principles, and has increased attention focused on the importance of supporting interdisciplinary initiatives to address complex problems affecting global society. The purpose of our study was to examine the experience of people participating in a specific university-funded interdisciplinary research initiative. As there is a strong emphasis within this program on reporting on the outcomes of the funding that supports interdisciplinary collaboration, our aim was to explore how participation may shape one's intellectual quality of life (iQoL) and how one's iQoL could be conceptualized and understood. Using a pragmatic constructivist case study, focus group and individual interviews were undertaken with 30 participants involved with university-funded interdisciplinary research teams. Findings illustrate that their iQoL was shaped by their capacity to engage in and achieve what they viewed as their core work and its outcomes. Related sub-themes addressed the social and relational climate, institutional environment and structure, and expectations and resources. We argue that further development of iQoL as a unique construct is required to adequately measure the full range of people's experiences in academia, particularly when aiming to address 'wicked' social and global problems within a predominantly neoliberal context. [ABSTRACT FROM AUTHOR]

Abstract: The Muskox mafic–ultramafic layered intrusion, Nunavut, is part of the widespread 1.27Ga Mackenzie large igneous province in northern Canada. The age and Nd–Hf isotope geochemistry of samples from the marginal zone of the Muskox intrusion and adjacent gneisses allow for an assessment of contamination mechanisms along the floor and walls of the intrusion, relationships between the marginal zone and overlying layered series, and genetic links with the Coppermine River flood basalts and Mackenzie dikes. The marginal zone, intersected in two diamond drill holes at stratigraphically low (West Pyrrhotite Lake) and high (Far West Margin) positions along the western margin of the intrusion, comprises a thick upper subzone (∼100–150m) of olivine and olivine–chromite cumulates and a relatively thin (<10m) lower subzone containing granophyre-bearing gabbronoritic rocks. U–Pb baddeleyite geochronology yields a crystallization age of the marginal zone of ca. 1269Ma based on dating of three samples (1268.8±1.7Ma, chromite-rich peridotite; 1268.7±2.9Ma, gabbronorite; 1271.5±3.4Ma, peridotite), which is synchronous with published ages from the layered series and Mackenzie dikes. The peridotites from both sections mostly span a restricted range of isotopic compositions (initial ɛ Nd =−2.8 to +0.5; initial ɛ Hf =−3.9 to +1.5), which is similar to that observed in the overlying layered series and consistent with the lack of significant chamber-wide crustal contamination of the Muskox parent magmas during differentiation and consolidation. In contrast, the gabbronorites within 10m of the margin of the intrusion (initial ɛ Nd =−13 to −5.5; initial ɛ Hf =−16 to −5.9) were strongly contaminated by melting and exchange with their respective host rocks; the extent of contamination is greater adjacent to paragneiss wallrocks than adjacent to orthogneiss. Crystallization of this thin, contaminated zone along the margin of the Muskox intrusion likely sealed the contacts with the host gneisses and prevented magmas within the interior of the chamber from interacting with the surrounding crustal rocks. Comparison of the Nd isotopic compositions from the marginal zone with published results from the layered series and the Coppermine River flood basalts indicates that only the lowermost portion of the volcanic succession (lower member of the Copper Creek Formation and lowermost part of the middle member) could represent residual magmas that resided and fractionated in the Muskox magma chamber prior to eruption. Construction of the Muskox layered intrusion was thus restricted to the early stages of emplacement of the Mackenzie large igneous province. [Copyright &y& Elsevier]

Abstract: A large part of the accreted Middle to Late Triassic Wrangellia oceanic plateau is exposed as a linear belt (<30 km×300 km) in southwest Yukon. The first major- and trace-element, and isotopic compositions of the Nikolai Formation in Yukon are presented here, along with compositions for underlying Paleozoic arc rocks. The Nikolai Formation in Yukon is predominantly massive tholeiitic subaerial flows (~1000 m) with no intervening sediments and a thin zone of pillow breccia along the base (<100 m). The Nikolai basalts unconformably overlie Late Paleozoic volcanic arc and marine sedimentary sequences and are overlain by Late Triassic limestone, which grades upwards into pelagic sediments. The Nikolai Formation is comprised of two distinct lava types: low-titanium basalts form most of the lower stratigraphy and high-titanium basalts form the upper parts of the volcanic stratigraphy. All of the low-titanium basalts (0.5–1.0 wt.% TiO2; 5.6–11.3 wt.% MgO) have prominent negative HFSE anomalies, whereas the high-titanium basalts (1.4–2.3 wt.% TiO2; 5.8–8.7 wt.% MgO) do not have HFSE anomalies and are more LREE-enriched. The low-titanium basalts are characterized by mostly higher initial ε Hf (+11.1 to +15.8) and lower initial ε Nd (+2.3 to +6.8) than the high-titanium basalts (initial ε Hf =+10.4 to +12.0; initial ε Nd =+6.6 to +9.0), and their Pb isotopic compositions overlap. Incongruent dynamic melting modeling of trace element compositions indicate the low-titanium basalts could have been derived from small degrees of melting (<5%) of Paleozoic sub-arc lithospheric mantle that was HFSE-depleted and evolved with high 176Hf/177Hf. The high-titanium basalts formed from melting of Pacific plume-type mantle, similar to the source of the Caribbean Plateau. Plume-derived melts dominated the upper stratigraphy of the oceanic plateau as a result of increased decompression melting of the underlying mantle plume in response to thinning of the lithosphere. [Copyright &y& Elsevier]

The Alpha–Mendeleev ridge complex is a prominent physiographic and geological feature ofthe Arctic Amerasia Basin. The Alpha and Mendeleev ridges are, respectively, the eastern andwestern components of a continuous seafloor high that is approximately 2000 km long and200–400 km wide. A surge of interest in the tectonic evolution of Arctic submarine featureshas led to a wealth of new geophysical data collected from the Alpha Ridge. Currentinterpretations of its origin vary but there is compelling evidence that the Alpha Ridge mayhave formed as an oceanic plateau during the Late Cretaceous. Geological samples are rarebut most samples recovered indicate a genetic link with the High Arctic Large IgneousProvince (HALIP). In August 2016, Canada&#x2019;s Extended Continental Margin-United Nations Convention onthe Law of the Sea Program dredged approximately 100 kg of volcanic rocks from the AlphaRidge. The large size and pristine state of the samples enabled the first comprehensive studyof a single eruptive event in the volcanic record of the Alpha Ridge. The dredgesample is a lapilli tuff containing vitric and basaltic clasts. Textural evidence and thecoexistence of juvenile and cognate clasts suggest a phreatomagmatic eruption. Thevitric fragments consist of sideromelane glass with abundant plagioclase microlites.Texturally, these basaltic glass lapilli display a fresh glassy core surrounded byFe- and Ti-rich zones and a palagonite rim. Major and trace element analyses ofglassy cores indicate remarkably uniform, mildly alkaline basaltic compositions. Theplagioclase-bearing glass yielded a 40Ar/39Ar plateau age of 90.40 ± 0.26 Ma (2σ error)which included 89% of 39Ar released. We interpret this result to represent the eruption age ofthe plagioclase microlites and consequently, of the host basaltic glass lapilli inthe tuff. Volatile species analyses by infrared spectroscopy on the fresh basalticglass suggests that the melt was effectively degassed to shallow level. Assumingequilibrium degassing, the homogeneous resulting values of H2Ototal in the range0.1 to 0.19 wt.% (1σ error) indicate subaerial or shallow eruption (surface to 80m). The new 40Ar/39Ar age for the sample is consistent with a 40Ar/39Ar age of 89 ± 1 Maobtained for a sample of tholeiitic basalt dredged from the central part of the Alpha Ridge,and with the range of ages reported for HALIP igneous rocks exposed onshore in theCanadian Arctic Archipelago (130-80 Ma). Our new data provide evidence for localemergence of the Alpha Ridge in the Late Cretaceous. A comparison of the Alpha Ridge andKerguelen Plateau–Broken Ridge Large Igneous Province (LIP) provides new insights on theepisodic nature of LIP magmatism and variations in eruptive style through time. [ABSTRACT FROM AUTHOR]