Faculty and Staff Publications

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Bending the rules? Including animals in a substantive account of the rule of law
(McGill Law Journal — Revue de droit de McGill, 2025) Deckha, Maneesha; Powell, Alexa
This article explores the relationship between the rule of law and the situation of nonhuman animals. A commonplace view prevails that the rule of law in anthropocentric legal systems is unrelated to how we treat animals. In those rare instances when jurists have framed the legal treatment of animals as a rule of law problem, the connection has been a limited one (i.e., the rule of law is said to be violated when governments fail to enforce existing laws for animals’ benefit). This article presses the connection between the rule of law and animal justice beyond the issue of poor enforcement of anticruelty laws to build upon nascent scholarship theorizing legal systemic animal use as presenting a constitutional problem implicating the rule of law. The article asks whether Canadian jurisprudence contains precedent for a “thicker” vision of the rule of law that can incorporate animal interests in its purview to generate a higher standard of animal protection than the very little that currently exists. The article concludes that it does. Although the “thinner” version is the onethat has been more frequently articulated by the Supreme Court of Canada, the analysis charts the significant precedent for a substantive vision, arguing that such a vision could theoretically extend to animals and that this doctrinal opening should not be summarily closed by ongoing anthropocentric reasons. The article further highlights existing legal commitments outside of conventional rule of law doctrine, namely reconciliation with Indigenous legal orders and adherence to customary international environmental law and developments in transnational environmental litigation, as additional doctrinal grounds as to why Canadian legal conversations and reasoning about what the rule of law means and protects should consider an animal-inclusive vision. RÉSUMÉ Cet article explore la relation entre la primauté du droit et la situation des animaux non humains. Il est communément admis que la primauté du droit dans les systèmes juridiques anthropocentriques n'a aucun lien avec la façon dont nous traitons les animaux. Dans les rares cas où les juristes ont présenté le traitement juridique des animaux comme un problème de primauté du droit, le lien a été limité : la primauté du droit est considérée comme violée lorsque les gouvernements n'appliquent pas les lois existantes au bénéfice des animaux. Cet article approfondit le lien entre la primauté du droit et la justice animale au-delà de la question de la mauvaise application des lois anti-cruauté, pour s’appuyer sur les travaux de recherche naissants qui théorisent l’utilisation systémique des animaux comme un problème constitutionnel impliquant la primauté du droit. L’article se demande si la jurisprudence canadienne contient des précédents en faveur d'une vision plus « épaisse » de la primauté du droit, capable d’intégrer les intérêts des animaux dans son champ d’application afin de générer un niveau de protection animale plus élevé que le très faible niveau actuel. L’article conclut par l’affirmative. Bien que la version la plus « légère » soit celle qui a été le plus souvent formulée par la Cour suprême du Canada, l’analyse retrace le précédent significatif en faveur d’une vision substantielle, soutenant qu’une telle vision pourrait théoriquement s’étendre aux animaux et que cette ouverture doctrinale ne devrait pas être sommairement fermée par des raisons anthropocentriques persistantes. L’article met également en évidence les engagements juridiques existants en dehors de la doctrine conventionnelle de la primauté du droit, à savoir la réconciliation avec les ordres juridiques autochtones et le respect du droit international coutumier de l’environnement, ainsi que l’évolution des litiges environnementaux transnationaux, comme fondements doctrinaux supplémentaires expliquant pourquoi les discussions et le raisonnement juridiques canadiens sur ce que signifie et protège la primauté du droit devraient envisager une vision inclusive des animaux.
Digital artifacts of self-representation: A critical qualitative analysis of nursing memes
(Nursing Inquiry) Hubert, Jaymelyn; Beaumont, Madelaine; Bungay, Vicky; Slemon, Allie
Stereotypes in mass media depict harmful and inaccurate portrayals of nurses and nursing work. As memes are understood to be units of culture, they may be examined as artifacts, deepening understandings of contemporary culture. This critical qualitative analysis of nursing memes from two popular social media platforms seeks to identify current cultural narratives and social meanings of nursing reproduced within the public domain. Memes were selected from popular hashtags and nursing meme accounts with more than 2500 followers. Memes were included if they followed traditional meme format and content-centered discourses of gender, race, and other aspects of power and oppression within nursing and healthcare systems. Our analysis employed a qualitative descriptive design within an overarching critical social theoretical framework. We identified that nursing memes reproduced stigmatizing and discriminatory narratives of patients and perpetuated harmful notions of "who" nurses are and "what" nurses do, while also drawing attention to systemic challenges facing the profession. Memes therefore serve as a valuable artifact for communicating contemporary cultural narratives about nursing and nursing work. Generating and distributing memes to raise awareness of systemic pressures may serve as a valuable social strategy toward advocating for systemic shifts in nursing and healthcare to address persistent challenges.
Conserved sequence identification within large genomic datasets using 'UNIKSEQ2': Application in environmental DNA assay development
(Molecular Ecology Resources) Lopez, Mark Louie D.; Warren, René L.; Allison, Michael J.; Coombe, Lauren; Imbery, Jacob J.; Birol, Inanc; Helbing, Caren C.
Identification of conserved genomic sequences and their utilisation as anchor points for clade detection and/or characterisation is a mainstay in ecological studies. For environmental DNA (eDNA) assays, effective processing of large genomic datasets is crucial for reliable species detection in biodiversity monitoring. While considerable focus has been on developing robust species-targeted assays, eDNA assays with broader taxonomic coverage (e.g., detecting any species within a taxonomic group such as fish), can significantly streamline environmental monitoring, especially when detecting individual species' DNA proves challenging. Designing such assays requires identifying conserved regions representing the target taxonomic group, a chiefly manual task that is often labor-intensive and error-prone, particularly when working with large sequence datasets. To address these challenges, we present unikseq2, an enhanced, alignment-free, k-mer-based tool for identifying unique and conserved sequences. It introduces a new functionality to identify sequence conservation among target species, enabling more informed marker selection for applications such as universal primer design. This automates sequence selection in large-scale mitochondrial genome datasets eliminating the need for manual inspection of computationally costly multiple sequence alignments. Herein, we demonstrate unikseq2's capabilities by developing and validating eDNA assays for various taxa, including Osteichthyes (bony fishes), the Salmonidae family (salmon and trout), Myotis bats and Cervus deer. Unikseq2-based eDNA assays allow for accurate detection across multiple taxonomic levels, from genus to class, enhancing the flexibility, scalability and reliability of eDNA tools in environmental monitoring. By leveraging genomic data from public repositories, unikseq2 supports efficient, reproducible assay design, making it an invaluable tool for a wide range of ecological and biodiversity research applications.
Social theory in nursing scholarship, from humanism to post-humanism: Revisiting S. Nairn on the structure–agency debate
(Nursing Philosophy) West, Crystal A.; Petrovskaya, Olga
Agency and structure are notable concepts in nursing philosophy and research. In this paper, we revisit two articles by Stuart Nairn which contrast selected theoretical perspectives exemplifying different positions within the structure-agency debate. Nairn's chief argument in 2009 was that nursing scholarship overemphasized the role of agency while neglecting the concept of social structure. The goal of Nairn's articles was to remedy this asymmetrical perspective. Building on his analyses of Lévi–Strauss, Parsons, Giddens, Archer, and Bourdieu, and the nursing examples he employed, we critique and extend Nairn's contributions by situating the structure-agency debate within the broader context of sociological theory. We suggest that his included theoretical perspectives largely assume agency to be an exclusively human attribute. Recent developments in critical posthumanism challenge this anthropocentric view, conceptualizing agency as distributed across human and nonhuman actors. Recognizing that differing approaches to structure and agency carry distinct implications for nursing knowledge and practice, we call for nurse scholars to make explicit their theoretical commitments when engaging these concepts in research and theorizing.
Beam collimation and filtration optimization for a novel orthovoltage radiotherapy system
(Medical Physics) Clements, Nathan; Masella, Olivia; Krim, Deae-Eddine; Braun, Lane; Bazalova-Carter, Magdalena
Background: The inaccessibility of clinical linear accelerators in low- and middle-income countries creates a need for low-cost alternatives. Kilovoltage (kV) x-ray tubes have shown promise as a source that could meet this need. However, performing radiotherapy with a kV x-ray tube has numerous difficulties, including high skin dose, rapid dose fall-off, and low dose rates. These limitations create a need for highly effective beam collimation and filtration. Purpose: To improve the treatment potential of a novel kV x-ray system by optimizing an iris collimator and beam filtration using Bayesian techniques and Monte Carlo (MC) simulations. Methods: The Kilovoltage Optimized AcceLerated Adaptive therapy system's current beam configuration consists of a 225 kVp x-ray tube, a 12-leaflet tungsten iris collimator, and a 0.1 mm copper filter. A Bayesian optimization was performed for the large and small focal spot sizes of the kV x-ray tube source at 220 kVp using TopasOpt, an open-source library for optimization in TOPAS. Collimator thickness, copper filter thickness, source-to-collimator distance (SCD), and source-to-surface distance (SSD) were the variables considered in the optimization. The objective function was designed to maximize the dose rate and the dose at a depth of 5 cm while minimizing the beam penumbra width and the out-of-field dose (OFD), all evaluated in a water phantom. Post-optimization, the optimal beam configuration was simulated and compared to the existing configuration. Results: The optimal collimation setup consisted of 2.5 mm thick tungsten leaflets for the iris collimator and a 350 mm SSD for both focal spot sizes. The optimal copper filtration was 0.22 mm for the large focal spot and 0.15 mm for the small focal spot, with a SCD of 148.5 mm for the large focal spot and 125.8 mm for the small focal spot. For the large focal spot, the surface dose rate decreased by 9.4%, while the PDD at 5cm depth (PDD5cm) increased by 7.7% compared to the existing iris collimator. Additionally, the surface beam penumbra width was reduced by 31.3%, and no significant changes in the OFD were observed. For the small focal spot, the surface dose rate for the new collimator increased by 3.7% and the PDD5cm increased by 5.3%, with no statistically significant changes in the beam penumbra width or OFD. Conclusion: The optimal beam collimation and filtration for both x-ray tube focal spot sizes of a kV radiotherapy system was determined using Bayesian optimization and MC simulations and resulted in improved dose distributions.
Adjustment for inconsistency in adaptive phase 2/3 designs with dose optimization
(Pharmaceutical Statistics) Chen, Cong; Huang, Mo; Zhang, Xuekui
Adaptive Phase 2/3 designs hold great promise in contemporary oncology drug development, especially when limited data from Phase 1 dose-finding is insufficient for identifying an optimal dose. However, inconsistent results between Phase 2 and Phase 3 may raise regulatory and practical concerns. The imperfection in dose selection further complicates the issue. In this paper, we explicitly incorporate the concerns about inconsistency into the statistical analysis under three hypothesis testing strategies (conservative, aggressive, and neutral) by specifying an inconsistency cutoff and accounting for the probability of "picking-the-winner." This investigation illustrates how to balance regulatory caution, sponsor interests, and practical considerations in adaptive Phase 2/3 designs with dose optimization, which paves the way for further research in a less explored area.
Assessment of teabag litter decomposition as a measure of soil health, including sensitivity to crop type and management system in agricultural soils
(Soil Use and Management) Hayes, E. Brooke; Norris, Charlotte E.; Volpe, John P.
Soil biota contribute to soil function and health, yet accessible and cost-effective methods for assessment remain limited. This study evaluated teabag litter decomposition as a potential biological soil health measure by examining its relationship to commonly used soil measures. In addition, litter decomposition sensitivity to crop type (annual vegetables, perennial fruit and trees and grain/forage) and agricultural management systems (conventional, organic and regenerative) was assessed. Fifty-seven farms from across British Columbia (BC), Canada completed three replicates of teabag litter decomposition trials and provided management system and crop production data from 171 fields. In-depth chemical, physical and biological soil health measures were taken from a subset of 35 farms across a local bioregion with similar climatic and environmental conditions (Vancouver Island). Correlation between laboratory and teabag measures and LASSO and random forest (RF) analyses were used to assess the sensitivity of commonly used chemical, physical and biological soil health measures to each other and to crop type and management system. Our focus is to determine the effectiveness of Tea Bag Index (TBI) measures (S, k) and the individual mass remaining of red Rooibos and green tea (Br, Bg), relative to standard laboratory measures, especially across varying crop types and management systems. Both LASSO and RF analyses identified the measure of the rate of biological decomposition of red Rooibos tea (Br) over 90?days as the most consistent and effective soil teabag measure in differentiating both crop type and management system. The decomposition of red tea (Br) was lowest in conventional fields and significantly higher in organic and regenerative systems, suggesting greater biological activity in these fields. This regional study demonstrated that mass remaining of red tea over a 3-month in situ incubation period was a reliable and accurate soil health measure, providing an opportunity to significantly increase access to and reduce costs in measuring and monitoring soil health across varied environments and management systems.
A tale of two shrimps—Speciation and demography of two sympatric shrimp species from hydrothermal vents
(Molecular Ecology) Methou, Pierre; Johnson, Shannon B.; Sherrin, John; Shank, Timothy M.; Chen, Chong; Tunnicliffe, Verena
Hydrothermal vents can serve as natural laboratories to study speciation processes due to their fragmented distribution, often with geographic barriers between habitats. Two sympatric species of Rimicaris shrimps occur at vents on the Izu-Bonin-Mariana volcanic arc: Rimicaris loihi also occurs near Hawai'i and R. cambonae is present on the Tonga Arc. These two species biogeographically co-occur and are genetically similar, raising questions about their speciation mechanisms, how they maintain distinct species, and whether interbreeding occurs. Here, we used barcoding and shotgun sequencing to test their genetic isolation and investigate their speciation process. We also evaluated population demography over 10 years to assess population densities and sex ratios at vents. Our results supported R. cambonae and R. loihi as two distinct species despite sympatry throughout part of their range. We also observed regional-scale genetic structure among R. loihi populations from the Izu-Bonin-Mariana volcanic arc, despite high dispersal potential. Finally, we found concomitant variations of shrimp densities and genetic diversity following fluctuations in geological and venting activities over a decade. A combination of geological instability, ocean currents dynamics and sea-level changes might drive temporary isolation among these local populations. We suggest that similar factors, with longer isolation periods, may also have promoted speciation between the two Rimicaris species, whereas distinct life-history traits could strengthen and maintain reproductive barriers. Overall, we found that the two species with large geographic distributions had significant patterns of genetic partitioning on a volcanic arc; this scenario contrasts with those observed previously at vents from mid-ocean ridges or back-arc basin systems.
Radiotherapeutic efficacy of gold nanoparticles for high dose-rate brachytherapy compared to conventional radiotherapy: An in vitro study
(Medical Physics) Cecchi, Daniel; Jackson, Nolan; Goharian, Mehran; Beckham, Wayne; Chithrani, Devika
Background: Radiation therapy is a pivotal part of the treatment plan for many cancer patients. Effective dose escalation in the tumour is required to achieve optimal curative results but is hindered by normal tissue toxicity. Gold nanoparticles (GNPs) as radiosensitizers to improve the radiation cross-section of malignant tissue is one avenue currently being explored to improve therapeutic results. It is hypothesized that at lower incident photon energies, dose enhancement from GNPs should be significantly greater compared to high-energy irradiations due to a greater photoelectric cross-section. Purpose: To assess GNP radiosensitization in vitro during low-energy, high-dose-rate brachytherapy (HDR-BT) irradiations and compare to the measured radiosensitization from a 6MV photon beam from a clinical linear accelerator (LINAC). Methods: A novel Solid Water Phantom was developed for uniform irradiations from a common HDR-BT source (192-Ir) and verified using EBT-4 radiochromic film. HeLa (cervical) and PC3 (prostate) monolayer cell cultures were used to represent common HDR-BT treatment sites. The cells were dosed at 10 µg/mL concentration with functionalized 12 nm spherical GNPs. GNP uptake in the cellular membrane was quantified using live-cell imaging and a trace element analysis technique. Cell cultures with or without GNPs were irradiated from the 192-Ir source or clinical 6 MV photon beam from a LINAC to a 200 cGy dose prescription. Cellular viability was measured using a clonogenic assay and DNA double-strand break (DSB) assay. Results: Endocytosis of spherical GNPs was confirmed 24 h post-incubation, resulting in an average of 8.7 x 105 GNPs/cell and 6.0 x 105 GNPs/cell for HeLa and PC3 cell cultures, respectively. The incorporation of GNPs induced 183% (p < 0.001) and 364% (p = 0.01) greater DNA DSBs with HDR-BT irradiations compared to LINAC irradiations for HeLa and PC3 cells, respectively, after the 200 cGy prescription. GNPs reduced the survival fraction of HeLa and PC3 cells after 2 weeks post-irradiation by 4.6% (p < 0.05) and 8.5% (p < 0.05), respectively, with HDR irradiations compared to LINAC irradiations. Conclusions: Our results suggest GNP incorporation into HDR-BT is a viable and effective treatment strategy. As our dosing concentration in this study induced no measurable cellular toxicity, this strategy has the potential to be implemented in clinical scenarios. Ultimately, we believe that incorporating GNPs into radiotherapy workflows can increase radiotherapeutic efficacy, improving the quality of life for cancer patients.
Integration before multiculturalism
(Nations and Nationalism) Eisenberg, Avigail
Despite research which shows that, over the last 40 years, most Western states have steadily enhanced their multicultural policies, on the ground, reality tells a different story. Today, Western governments are closing their borders and reversing long-standing programmes that welcomed newcomers, whereas immigrants continue to be targets of hostile majority groups. This paper explores three lessons that can be learned from approaches to social integration defended by mid-century American thinkers during the civil rights era and their relevance for debates about multicultural integration today. The first lesson is that legal rights are not effective at creating an integrated society. Second, integration is a transformative project that depends on empowering minorities through their active participation. Third, one of the chief obstacles to a successful, normatively attractive approach to integration is resistant majorities rather than reluctant minorities. Even though the project of multicultural integration is different from the project of racial integration, mid-century ideas about the social integration of a racist society focused on concerns familiar and helpful within multicultural contexts. The aim here is to strengthen our understanding of integration by exploring features of these mid-century ideas relevant to multicultural debates today.
Exploring iron deposition patterns using light and electron microscopy in the mouse brain across aging and Alzheimer's disease pathology conditions
(Journal of Neurochemistry) Lau, Victor; VanderZwaag, Jared; Murray, Colin J.; Tremblay, Marie-Ève
Alzheimer's disease (AD) involves cognitive decline, possibly via multiple concurrent pathologies associated with iron accumulation. To investigate if iron accumulation in AD is more likely due to pathological iron-rich compartments, or a compensatory response of iron within oligodendrocytes to disease progression, we sought to quantify iron-rich staining (via Perl's diaminobenzidine; DAB). Healthy wild-type (WT) and APPSwe-PS1?e9 (APP-PS1; amyloid-beta overexpressing) male mice were examined during middle age, at 14?months. The frontal cortex, a brain region affected over the course of dementia progression, was investigated. Iron-rich compartments were found across genotypes, including oligodendrocytes and immune cells at the blood-brain barrier, and exclusively amyloid plaques in the APP-PS1 genotype. A semi-automated approach was employed to quantify the staining intensity of iron-rich compartments with light microscopy. Mouse frontal cortex of each genotype was also assessed qualitatively and ultrastructurally with scanning electron microscopy, to novelly discern and confirm iron-rich staining (via Perl's DAB). We found parenchymal iron staining corresponding to oligodendrocytes, pericytes, astrocytes, microglia and/or infiltrating macrophages, and amyloid plaques; increased iron deposition and clustering were detected in middle-aged male APP-PS1 versus WT frontal cortex, supporting that AD pathology may involve greater brain iron levels and local clustering. Unexpectedly, iron-rich cells were enriched at the central nervous system (CNS) interface and perivascular space in control and APP-PS1 mouse models, with ultrastructural examination revealing examples of these cells loaded with many secretory granules containing iron. Together, our results provide novel exploration and confirmation of iron-rich cells/compartments in scanning electron microscopy and reinforce literature that iron deposition is relatively increased in AD over healthy cognitive aging and involves greater local clusters of iron burden. Increased iron burden along the aging trajectory, regardless of cognitive status, may also be attributed to novelly discovered iron-rich cells secreting granules along the CNS border. See PDF for illustration in abstract.
Highly resolved surface phytoplankton community composition along the British Columbia coast, derived from in situ hyperspectral radiometry
(Journal of Geophysical Research Biogeosciences) Vishnu, Perumthuruthil S.; Del Bel Belluz, Justin; Xi, Hongyan; Hussain, Midhun S.; Bracher, Astrid; Costa, Maycira
Quantitative measurements of phytoplankton community composition (PCC) are essential for understanding fisheries production, ocean nutrient cycling, and the export of particulate carbon to the ocean interior. However, these measurements are constrained in dynamic coastal waters due to the spatial-temporal constraints of in situ sampling, difficulty quantifying communities, and the challenges of deriving community compositions via satellites. Here, we work to address these issues by using highly resolved in situ hyperspectral radiometry, along a ship of opportunity track through Case-2 waters of the Strait of Georgia (SoG) British Columbia, to derive phytoplankton community composition. First, an empirical orthogonal function (EOF)-based algorithm was developed using HPLC CHEMTAX-derived phytoplankton group-level chlorophyll-a (Chla) and Total Chla (TChla) concentrations and corresponding principal components derived from hyperspectral remote sensing reflectance. Second, the outputs were evaluated using cross-validation, showing good retrievals for TChla and the regionally dominant phytoplankton groups: diatoms, cryptophytes, green algae, and raphidophytes, which followed expected spatial-temporal trends with diatom-dominated spring blooms and succession to high diversity flagellate-dominated summer conditions. Furthermore, the outputs captured fine spatial scale trends including strong harmful raphidophyte blooms over the narrow transition to low salinity Fraser River plume influenced waters. These findings highlight the potential of using highly resolved hyperspectral radiometry to derive fine-scale trends in phytoplankton group level community composition in optically dynamic coastal waters. Coupled with additional measures, this method could provide valuable information on phytoplankton dynamics in the SoG, which is a critical habitat for a high diversity of pelagic fish species, including Pacific salmon.
Assessing winter phytoplankton community composition dynamics and their response to environmental drivers in the Subarctic Northeast Pacific
(Journal of Geophysical Research Oceans) Vishnu, Perumthuruthil S.; Del Bel Belluz, Justin; Peña, Angelica; Hunt, Brian P.V.; Vazhova, Anna; Hussain, Midhun S.; Xi, Hongyan; Bracher, Astrid; Costa, Maycira
The subarctic northeast Pacific (SNEP) is a high-nutrient, low-chlorophyll region where primary productivity is limited by bioavailable iron during the spring through autumn, and by light limitation during winter. Here, we investigate the spatio-temporal distribution and drivers of SNEP surface phytoplankton biomass and community composition in the winters of 2019 and 2020 using in situ environmental data, chemotaxonomic analysis of phytoplankton pigment samples, and Sentinel-3A Ocean Land Color Instrument imagery. The utilized satellite-based algorithm showed promise replicating the expected trends of: (a) homogenous phytoplankton communities dominated by haptophytes, green algae, and pelagophytes in highly mixed light-limited oceanic waters and; (b) increased diatoms in coastal Haida Gwaii waters with reduced mixed-layer depth (MLD) and salinity. Unexpectedly, increases in cryptophytes were observed in the northern extents of the SNEP, which coincided with winter marine heatwave driven reductions in MLDs and also the presence of a mesoscale eddy. This finding highlights a deviation from expected homogeneous phytoplankton conditions, which may be systematically missed by spatially and temporally constrained in situ sampling. The further advancement and deployment of the satellite-based algorithm could significantly expand the understanding of winter phytoplankton dynamics in the SNEP, a critical period for Pacific salmon survival, improving the understanding of trophic linkages and match/mismatch dynamics, and contributing to improve the forecasting of salmon returns.
Leveraging crowdsourced data for extreme heat monitoring
(International Journal of Climatology) Azargoshasbi, Forood; Vahmani, Pouya; Minet, Laura
The combined effects of urban microclimate heterogeneity and climate change exacerbate the disproportionate impact of heatwaves on urban areas, a trend expected to intensify. Crowdsourcing is a promising tool to monitor temperatures at a high spatiotemporal scale, which is now deemed critical. However, quality control is essential before the use of such data. Traditional quality control methods often fail to capture short extreme weather events like heatwaves, as they frequently eliminate crucial observations from these intense, brief episodes. Here, a quality control methodology, tailored to short-term heatwaves built on existing quality control methods, is introduced and tested on crowdsourced monitoring networks for five North American cities and three heatwave episodes. This framework is centred around a systematic comparison with traditional weather stations. The results show that the designed procedure can effectively filter out false data points and corrupt stations whilst preserving observational data points capturing heatwaves. In the worst case, 24.7% of a heatwave episode's records are eliminated, compared to 75% using an existing detailed quality control method. We further show that crowdsourced monitoring could bring more insight into the spatiotemporal variability of temperature and living experiences during heatwaves compared to the sparse traditional weather station networks.
Indigeneity, caste, tribe and the limitations of decolonial thought in South Asian socio–legal studies: The need for a decolonial–debrahmanical approach
(Journal of Law and Society) Kumar, Arvind
The dominant decolonial approach in Adivasi studies and South Asian socio-legal studies is broadly and primarily rooted in a critical study of the British colonial rule, epistemologies, laws and institutions, as they are considered to be the roots of social, cultural, religious, legal and political challenges faced by post-colonial India. Therefore, in common vocabulary, the decolonial or decolonisation approach is synonymous with identifying and dismantling the legacies of colonial rule and epistemologies. This paper highlights the limitations of the dominant decolonial approach in relation to post-colonial discourses vis-à-vis categories of caste and tribe. I argue that the classification of social groups into caste and tribe has more to do with Brahmanical epistemology than colonial epistemology. Subsequently, drawing upon Adivasi oral narratives from the field, this paper argues that there is a need to look beyond the prevailing decolonial approach and consider a decolonial–debrahmanical approach to address the decolonial challenges in post-colonial India.
Investigating how all-trans retinoic acid polycaprolactone (ATRA-PCL) microparticles alter the material properties of 3D printed fibrin construct
(Macromolecular Bioscience) Hangad, Maria V.; Forigua, Alejandro; Scheck, Kali; Willerth, Stephanie M.; Elvira, Katherine S.
The 3D printing of human tissue constructs requires carefully designed bioinks to support the growth and function of cells. Here it is shown that an additional parameter is how drug-releasing microparticles affect the material properties of the scaffold. A microfluidic platform is used to create all-trans retinoic acid (atRA) polycaprolactone (PCL) microparticles with a high encapsulation efficiency (85.9 ± 5.0%), and incorporate them into fibrin constructs to investigate their effect on the material properties. An encapsulation that is around 25–35% higher than the current state of the art batch methods is achieved. It is also found that the drug loading concentration affects the microparticle size, which can be controlled using the microfluidic platform. It is shown that the release of atRA is slower in fibrin constructs than in buffer, and that the presence of atRA in the microparticles modulates both the degradation and the rheological properties of the constructs. Finally, it is shown that the fibrin material exhibits a stronger solid-like state in the presence of atRA-PCL microparticles. These findings establish a basis for understanding the interplay between drug-releasing microparticles and scaffold materials, paving the way for bioinks that achieve tailored degradation and mechanical properties, together with sustained drug delivery for tissue engineering applications.
Trends and variability in depth and spiciness of subsurface isopycnals on the Vancouver Island continental shelf and slope
(Journal of Geophysical Research Oceans) Maier, Michaela; Ianson, Debby; Hamme, Roberta C.
The waters over the southern Vancouver Island shelf and slope are productive, economically important regions. The circulation is highly dynamic through variable mixing of both younger subarctic and older southern water masses, and significant local upwelling and downwelling regimes. We take advantage of three time series that cover more than three decades: the La-Perouse, Line-P, and CalCOFI time series, each covering at least 37 years (1984-2021). We investigate subsurface salinity, temperature, and depth observations to study seasonal and interannual variability in isopycnal heave and spiciness, and evaluate possible trends. The 26.6 kg m?3 isopycnal is the deepest isopycnal that is regularly upwelled onto the Vancouver Island shelf (above 200 m), shoaling over 100 m seasonally. Spiciness on the 26.6 isopycnal is highest in winter, but seasonal variability is much smaller than the interannual variability, which itself is two to three times smaller than the variability in adjacent subarctic waters and in the California Undercurrent further south, prior to their arrival in our study region. Spiciness in subsurface shelf waters appears to have been increasing over the past 37 years, by about half the magnitude of the increase in spiciness observed in the California Undercurrent water. In contrast, the subsurface slope shows no trend in spiciness but appears to be experiencing physical convergence, specifically an increase in the volume of water with a density of around 26.6 kg m-3, which has also been observed in the subarctic northeast Pacific, at Ocean Station Papa.
On dislocation modeling of megathrust tsunami sources
(Journal of Geophysical Research Solid Earth) Zhu, Yijie; Wang, Kelin; Sun, Tianhaozhe; Carvajal, Matias; He, Jiangheng
Modeling tsunamis due to subduction earthquakes for scientific research and hazard assessment requires accurate quantification of coseismic seafloor deformation. Although the widely used analytical model of shear dislocation in a uniform elastic half space can accommodate complex fault geometry and slip distribution, it fails to capture the sloping seafloor topography and heterogeneous rock rigidity (shear modulus) in real subduction zones. In practice, these real-world complexities are either ignored or addressed by adjusting fault geometry and/or applying corrections to the deformation results, with consequences poorly understood. This study investigates the validity or errors of these simplifications by comparing dislocation model results with those from finite element models that account for these complexities. Our analysis reveals that the absence of the seafloor slope can be accurately compensated by adjusting the shallow geometry of the megathrust such that the fault depth below the flat model surface approximates the actual fault depth below the seafloor. Effects of short-wavelength bathymetry can be effectively incorporated by adding a commonly used gradient-based correction. For slip-to-trench ruptures, it is crucial to adjust fault geometry to ensure that the fault reaches the model surface at the trench; otherwise, the abrupt slip termination at a small depth creates an uplift spike which is a commonly seen artifact in tsunami source models. Our findings highlight the secondary or minimal effects of heterogeneous rigidity on tsunamigenic deformation if fault slip is kinematically assigned. This research offers guidance for the development of more accurate tsunami source models using analytical dislocation solution.
A longitudinal assessment of the impact of biological maturity and menarche on adolescents' organized sport and physical activity participation
(Journal of Adolescence) Gopalan, Sharan S.; O'Dean, Siobhan; Buckler, E. Jean; Liu, Sam; Gardner, Lauren A.; Champion, Katrina
Introduction: Processes accompanying growth and maturation are known to impact physical activity (PA) participation among adolescents. This study evaluated the longitudinal impact of these processes on organized sport participation and moderate-to-vigorous PA (MVPA) among male and female adolescents. Methods: This study used secondary analysis of data from a longitudinal cohort of 6639 adolescents (Age = 12.92 ± 0.81 years; Males = 3302; Females = 3226) collected using confidential, online self-report surveys through the Health4Life Study across 71 secondary schools in Australia from 2019 to 2022. Controlling for age, socioeconomic status, and state, mixed effects regression models assessed the impact of pubertal stage, relative pubertal timing, and period status (female adolescents only) on organized individual and team sports and MVPA participation. Results: While organized sport and MVPA participation reduced over time for all participants, male and female adolescents responded differently to puberty. Male adolescents showed marginally greater likelihood of participation in organized team sport during early puberty and individual sport during late puberty, but female adolescents significantly reduced individual sport participation during middle, late, and postpubertal stages. Relative pubertal timing did not impact male adolescents, but early maturing female adolescents were significantly less likely to participate in organized team and individual sports. Achieving menarche was linked to lower odds of individual sport participation only. Conclusions: Declining PA participation rates suggest that adolescents may need support for maintaining PA. Disparate effects of puberty in male and female adolescents advocate for separate approaches based on their specific characteristics. Future research should explore the impact of specific sport environment characteristics and menstrual cycle experiences on PA.
Transformative governance of cumulative effects through an Indigenous outlook
(Frontiers in Ecology and the Environment) Lawrence, Ignace
As the social–ecological challenges facing society grow in complexity and variability, transformative measures––those that seek to re-imagine conventional systems of sustainability and resource management––are increasingly needed. One system that has successfully demonstrated a degree of sustainability is that of Indigenous Knowledge (IK)––a long-standing societal system that places Indigenous Peoples' relationship with the environment above all else. As a body of knowing, IK is inextricably linked to Indigenous existence and identity as the means of maintaining the well-being of the living and non-living. Rarely investigated is the braiding of CEAM (cumulative effects assessment and management) with IK systems. Conventional resource management has long struggled to harness cumulative effects assessments and could be improved through the re-positioning of cumulative effects assessments and IK. The strengths of these systems together offer insight into how current conventional governance can be transformed to ensure a more equitable and sustainable future for Indigenous and non-Indigenous Peoples alike.

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