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Item Structural determination of a carbocation-derived rearrangement product observed during Thiele cage opening: Insight into the mechanism of an alkyl-extended pinacol reaction(Canadian Journal of Chemistry, 2024) Burman, Austin L.; Sader, Jonathan K.; Wulff, Jeremy E.A substituted bishomocubane structure colloquially known as a Thiele cage was previously observed to undergo an alkyl-extended pinacol-type rearrangement, wherein 1,2-aryl migration and ketone formation occurred together with (or at least in close succession to) opening of a strained cyclobutane bond. While there was some indication that the rearrangement reaction might proceed via a stepwise process involving a sequence of carbocation intermediates, previous studies did not uncover any direct evidence for the formation of carbocations, and did not fully explain the regio- and stereospecificity of the reaction. Here we describe the isolation and detailed characterization of a second rearrangement product formed under the pinacol reaction conditions, the existence of which implicates the formation of discrete carbocation intermediates along the reaction pathway. Observation of this new product also finally explains the fate of any Thiele cage material that is converted to a carbocation, but which is not geometrically predisposed to react through a facile 1,2-aryl migration. As such, our findings resolve previous questions surrounding the origin of regio- and stereospecificity in the alkyl-extended pinacol rearrangement.Item Polyamine–diazirine conjugates for use as primers In UHMWPE–epoxy composite materials(ACS Applied Polymer Materials, 2022) Nazir, Rashid; Bi, Liting; Musolino, Stefania F.; Margoto, Olivia H.; Çelebi, Kuthan; Mobuchon, Christophe; Takaffoli, Mahdi; Milani, Abbas S.; Falck, Greg; Wulff, Jeremy E.Ultra-high molecular weight polyethylene (UHMWPE) fibers show promise for use in fiber reinforced polymer composites, but have poor interfacial adhesion to the epoxy resin that would serve as the polymer matrix. Here we describe the development of a diazirine-grafted polyamine that can be used as a topically applied primer for UHMWPE fibers. Activation of the diazirine groups on the primer initiates C–H bond insertion on the polyethylene fiber, leading to strong covalent bonds between the fiber and the polyamine coating. The covalently functionalized surface can then engage in nucleophilic addition reactions with epoxy resin—resulting in increased bonding to the epoxy matrix (demonstrated through lap-shear experiments) and increased performance for fiber reinforced composite materials (demonstrated through lamination rates and short-beam stress measurements).Item Surface modification and dyeing of ultra-high-molecular-weight polyethylene fabrics using diazirine-based polymers(ACS Applied Polymer Materials, 2024) Nazir, Rashid; Musolino, Stefania F.; MacFarlane, Madisen A.; Wulff, Jeremy E.Ultra-high-molecular weight polyethylene (UHMWPE) fibers are valued for their high strength-to-weight ratio and are employed in a wide variety of commercial applications. However, because of its low surface energy, UHMWPE can fail in certain applications, such as fiber-reinforced composites. This is due to its poor interfacial adhesion with polar matrices, making it challenging to incorporate into composites and/or retain polar dyes or colorants. Herein, we describe the use of polyamine primers for coating UHMWPE weaves, covalently bonding the aliphatic chains through C−H insertion, leading to strong covalent interactions between fabric and polyamines. We further demonstrate that the polyamine-coated UHMWPE surfaces can successfully react with epoxy resin through nucleophilic addition reactions to enable the production of epoxy composites. Furthermore, we show the use of polyamine-coated UHMWPE in secondary functionalization with amine-reactive compounds, such as dyes, through covalent linkages that result in very strong color fastness.Item Design, exploitation, and rational improvements of diazirine-based universal polymer crosslinkers(ACS Accounts of Chemical Research, 2024) Lepage, Mathieu L.; Musolino, Stefania F.; Wulff, Jeremy E.Addition of new covalent bonds between the chains of thermoplastic polymers (i.e. crosslinking) provides improved mechanical strength and enhanced high-temperature performance, while also providing an effective strategy for photopatterning. Traditionally, however, crosslinking of each polymer substrate has required the use of a specific crosslinking technology (hydrosilylation for PDMS, vulcanization for rubber, etc.). The lack of a general solution to the challenge of polymer crosslinking means that there are many thermoplastics (e.g. polypropylene or polyhydroxyalkanoates) that have desirable properties, but which cannot be upgraded by traditional crosslinking technologies.Item The effects of cell culture conditions on premature hydrolysis of traceless ester-linked disulfide linkers(Journal of Drug Delivery Science and Technology, 2022) Blevins, Derek J.; Nazir, Rashid; Dabri, Seyed Mohammad Hossein; Akbari, Mohsen; Wulff, Jeremy E.Disulfide acids are important for traceless release mechanisms in prodrugs and drug delivery applications. Their ability to self-immolate and release cargo due to environmental stimulus is invaluable. However, complex reactivity patterns may be overlooked as assays increase in complexity or are conducted in media of increasing biological relevance. Conclusions drawn from preliminary characterization in simple phosphate buffers are often applied to in vitro studies in which more complex media are used (e.g. containing glucose, amino acids, FBS, and the cell surface). We developed a model disulfide incorporating a fluorogenic dye as a reporter group in order to explore the generality of the disulfide prodrug system, and used this to explore the stability of disulfide esters in various contexts of increasing complexity. We found that our reporter molecules prematurely released cargo in a series of cell-containing and cell-free assays. We systematically reverse-engineered the components of a complex cell medium and found that FBS was capable of interfering with disulfide-based prodrug linkers, triggering the release of conjugated 4-methylumbelliferone (4-MU) from representative reporter molecules. FBS consistently induced 4-MU release in complete media (i.e. DMEM and RPMI 1640), minimal essential media, and in pure water. Signs of 4-MU release were mitigated when FBS was subjected to intense heat (> 100 °C) or esterase-specific protease inhibitor cocktail (PIC), indicating that esterases from the serum were capable of triggering cargo release using a hydrolysis mechanism that is separate from the desired reductive cleavage pathway. These findings are important because they show that variance in models may hide unexpected results, which calls for more meticulous consideration of control experiments when developing stimulus-release agents for biological applications.Item Copolymers of functionalized and nonfunctionalized polydicyclopentadiene(ACS Applied Polymer Materials, 2020) Li, Tong; Wulff, Jeremy E.Polydicyclopentadiene (PDCPD) is a thermoset polymer that is valued in industry for its excellent mechanical properties, heat resistance and chemical tolerance. However, the commercial polymer lacks chemically tunable functionality. Recently, a methyl ester-modified polydicyclopentadiene (fPDCPD) was shown to offer significantly improved tunability while maintaining the same thermal stability as the unfunctionalized parent polymer. In this report, we describe the synthesis and characterization of poly(methyl ester functionalized dicyclopentadiene)-stat-(dicyclopentadiene) copolymers in which the mole fraction of the functionalized, ester-containing monomer, relative to the unfunctionalized dicyclopentadiene mono-mer, is systematically increased. Our data reveal an ability to tune physical and mechanical properties of the copolymers (e.g. alpha transition and hardness) by changing the monomer ratio and thermal curing time. Importantly, the copolymers retain the same thermal stability as the individual homopolymers, while allowing for increased control over surface energy.Item A Chan–Evans–Lam approach to trisubstituted vinyl ethers(Organic & Biomolecular Chemistry, 2021) Sader, Jonathan K.; Molder, Bryce A.; Wulff, Jeremy E.Trisubstituted vinyl ethers were accessed via Chan–Evans–Lam coupling of vinyl trifluoroborates and primary aliphatic alcohols. This approach complements prior methods that required the use of neat liquid alcohol coupling partners. A palladium-catalyzed redox-relay Heck reaction was used to convert several vinyl ethers into aldehyde-functionalized 1,3-dihydroisobenzofurans.Item Improving equity in Canada's low-carbon energy workforce: Learning from the lived experiences of diverse applicants to a grassroots bursary(2026) Jaradat, Arwa; Black, Rebecca; Hoicka, Christina E.Transitions to low-carbon energy systems require labour market transformations to support resilience, new technologies and infrastructures across communities. Despite rapid growth, the worldwide low-carbon energy sector remains one of the least diverse industries with persistent inequities. Despite steady job growth in the renewable energy sector, women’s overall representation has stagnated since 2019, which indicates the need for new approaches to remove barriers to their entry and retention in the sector. While most existing research on the low-carbon energy workforce relies on structured surveys, aggregate labour market data, or projections, far less is known about the lived experiences and motivations of equity-deserving groups entering the sector. This omission matters because mainstream data often overlooks the qualitative, values-driven perspectives and circumstances that shape career pathways—particularly those of women, newcomers, youth, Indigenous peoples, and LGBTQ+ workers. This study was designed using a co-creation research approach with a grassroots, community-led bursary - Trellis Bursary Fund - to analyze the 119 applications to this fund by an intersectional group of women. These were analysed against a theoretical framework of Alternative Pathways, Strategic Niche Management (SNM), and Feminist and Energy-Justice, to generate insights to improve equity in recruitment and retention in Canada’s low-carbon energy workforce. Our study’s contribution is to provide deeper insight into how small-scale, grassroots, flexible funding mechanisms developed within the communities that they serve can foster novel, justice-centred contributions that mainstream funding often overlooks. These insights offer a critical qualitative narrative-based counterpoint to workforce projections, showing that interest and ambition are not lacking; rather, systemic barriers are constraining entry and persistence of diversity in Canada’s low-carbon energy workforce.Item Bridging democratic member control and concern for community with stakeholder governance(Journal of Co-operative Studies, 2025) Pek, Simon; Billiet, AdrienTo foster concern for community, worker co-operatives need to complement their emphasis on democratic member control with meaningful consideration of their stakeholders’ perspectives. To help them do so, we synthesise five stakeholder governance practices that can be integrated into contemporary models of co-operative governance.Item Mapping of historical design values and their future-projected changes over Canada(New Horizons in Green Civil Engineering (NHICE), 2022-04-27) Curry, Charles L.; Annau, Nicolaas J.; Zwiers, Francis W.; Anslow, Faron; Glover, Rod; Hiebert, JamesClimate change has the potential to affect buildings and infrastructure by changing the conditions to which they are exposed. To better quantify and prepare for these changes, Infrastructure Canada and the National Research Council (NRC) recently supported a collaboration between the Pacific Climate Impacts Consortium (PCIC) and Environment and Climate Change Canada (ECCC) to develop updated guidance to the engineering community. One facet of this work was the provision of standard climatic design values based on up-to-date historical observations at meteorological stations. Climatic data for infrastructure design are often required at locations not co-located with stations, necessitating some sort of interpolation. Purely mathematical or statistical interpolation tends to oversmooth spatial structure in station-poor areas and, depending on the technique, can exaggerate station measurement error in station-rich areas. Nor is physical consistency of the underlying climatic field in space guaranteed. We developed an approach that uses historical regional climate model (RCM) simulations as a spatial interpolator of station observations. RCMs can adequately reproduce the observed spatial patterns and probability distributions of many climate variables, with the benefit of spatiotemporal consistency—albeit in a "model world" and at spatial scales resolved by the RCM. The mapping method has been implemented as an online tool (the Design Value Explorer, or DVE) for general users to explore design value variations across Canada. The seamless transition from historical to future climate states in the RCM further allows the tool to provide projected changes to design values indexed to different levels of global warming. In this short paper, we review the development of the Design Value Explorer online tool, and showcase its main features.Item Juvenile smokescreens: Softening the harm of zoos, aquaria, and prisons through (human) children(Cambridge University Press, 2022) Deckha, ManeeshaThis chapter explores how human children soften the abusive edge of carceral spaces. Prisons, immigration detention centres, and zoos and aquaria are institutions that attract sustained public scrutiny from prisoner rights, migrant rights, anti-racist, and animal rights movements. Critics and scholars note the entwined nature of race, gender, and species logics that shape and unite these spaces and object to the shortand long-term incarceration these institutions make possible as well as the conditions residents confined within experience. Prisoner rights, migrant rights, and animal rights critics also contest the messaging that these institutions and their proponents use to assure the public of the need for confinement and the ethical acceptability of the conditions captive animals and humans experience. These discourses, depending on the specific institution, highlight the larger public “law and order” interests of safety and border control, but also “progressive” interests of rehabilitation, conservation, and education. In highlighting these latter “progressive” interests, carceral institutions seek to humanize themselves and their work to bolster their social credibility. This “humane-washing” occurs through long-standing rationales about rehabilitation for offenders in the prison context, and more recent rationales about the conservation of nature and conservation education in the zoo and aquarium context. It also, I will argue, occurs through a specific type of marshaling of the human child. I seek to add to the literature on “humane-washing”4 as well as contestations and uses of “childhood” and “family” narratives in general in this analysis. I apply a multispecies lens to consider how the real and imagined human child in the zoo and aquaria context, and narratives about what is in the best interests of human children in the immigration and prison context, figure into characterizing such carceral institutions as legally and socially legitimate spaces. The argument acknowledges that these carceral spaces can yield positive benefits for some, such as rehabilitation or rescue of a specific individual or even conservation of a specific species. However, it accepts the existing critical scholarly literature against such spaces overall to focus on the question of how carceral spaces mask their problematic and oppressive nature by integrating the presence of human children.Item Animalization and dehumanization concerns: Another psychological barrier to animal law reform(Psychology of Human-Animal Intergroup Relations, 2023) Deckha, ManeeshaLegal systems across the world classify animals as property. There is growing global momentum asking courts in anthropocentric legal systems to revisit this position through test-case litigation. This has resulted in a few discrete victories for animals, but not much more. An ongoing issue is general legal conservatism and the belief in human exceptionalism that judges exhibit in these and related cases. In addition to general human exceptionalism, this article argues that a further psychological block for judges can arise from concerns about exacerbating racism and other intra-human prejudices given histories and legacies of animalizing and dehumanizing certain human groups. The first aim of this study is to illustrate this psychological phenomenon impacting judicial decision-making in relation to race. The article discusses the 2022 decision by the New York Court of Appeals with respect to the ongoing captivity of Happy, an elephant at the Bronx Zoo. This decision is selected given its recent and landmark status in North America. The second aim of the study is to outline why the dissociation of humans from animals is counterproductive to eliminating racism and other intra-human prejudices and inequities. The third aim of the study is to explain why affirming human proximity and kinship to animals—and thus putting a positive spin on animalization—in the legal system would be a more effective anti-racist and decolonizing gesture.Item Human children, nonhuman animals, and a plant-based vegan future(Koninklijke Brill NV, 2023) Deckha, ManeeshaConservative estimates indicate that humans eat approximately 65 billion land-based animals annually (FAO 2020a), and that wild-caught fishing and aquaculture entail the death of nearly a trillion (and quite possibly more) fish per year. The enormity of this scale of animal consumption is unprecedented in human society. Yet, most people are unaware of the scale of animal farming, trawling, and slaughter or the brutalities it involves as these activities take place away from public view, typically in windowless concentrated animal feeding operations or in gigantic trawler nets in the middle of the ocean (Bisgould 2011, 162–163). Media coverage discussing the phenomena, even in affluent countries with the highest levels of animal consumption per capita, is sparse with national governments also remaining silent on farmed animal suffering (Arcari 2017, 77–82). In fact, meat, dairy, and animal-based food lobbies enjoy elevated levels of political influence (Kemmerer 2006), and legislation may also exist in certain jurisdictions to illegalise whistleblowing or undercover investigations in these spaces. All of these forces combine to minimise public awareness of the scale of these industries and the torturous conditions in which animals are raised, slaughtered, and otherwise processed.Item Supplanting anthropocentric legalities: Can the rule of law tolerate intensive animal agriculture?(Routledge, 2023) Deckha, ManeeshaThe rule of law is a concept in motion. Whether adopted as foundational to the constitutional backdrop of nation-states or circulating as a higher-order international law general principle of law, the now-transnational concept defies a fixed meaning and has been subject to multiple interpretations. Its open-endedness permits it to attend to pressing social problems and matters of justice heretofore unseen or undertheorized and which exceed its normal liberal legal parameters and colonial formation. In this contribution, I suggest that the rule of law is deployable against the planetary scourge of animal-based food systems (ABFS) and the more-than-human violence ABFS occasion. Drawing on posthuman feminist theory, the chapter contributes to the growing field of global animal law that explores animal law issues through international law and transnational law frameworks (Blattner 2019; Cao et al 2016; Peters 2020, 2017, 2016: 3–4; Stucki 2017), by highlighting the potential of the rule of law to challenge the legitimacy of at least some forms or portion of ABFS.Item Accelerating animal replacement: How universities can lead — results of a one-day expert workshop in Zurich, Switzerland(Alternatives to Laboratory Animals, 2025) Deckha, Maneesha; Michel, Margot; Azilagbetor, David; Blattner, Charlotte; Morales, Rosa M. C.; Davies, Gail; Elger, Bernice; Faizee, Sara; Fox, Marie; Gerritsen, Vanessa; Heuss, Adrian; Kämpfen, Laura; Louis-Maerten, Edwin; Lüthi, Nicole; Milford, Aoife; Müller, Nico D.; Persson, Kirsten; Ritskes-Hoitinga, Merel; Rothen-Rutishauser, Barbara; Rüttimann, Andreas; Stoykova, Katerina; Stucki, Saskia; Zemanova, Miriam A.This report is a result of an interdisciplinary workshop held at the Collegium Helveticum in Zurich, Switzerland in February 2024, in which ideas for accelerating NAMs (New Approach Methodologies) in Swiss universities were shared and discussed. Due to regional differences in university organisation and funding structures, not all recommendations will be transferable to all regions worldwide. All participants were qualified to contribute to the discussion, due to their knowledge and experience of the Three Rs, in particular with regard to their implementation. The workshop participants believed that universities, which play a pioneering role in so many other areas, should also exploit their innovative potential in the field of animal-free research. The workshop uncovered four areas that would need to be addressed in order to achieve a significant change in university science culture and do more justice to the Three Rs, namely: language — innovative framing (pro-replacement framing in official university statements); knowledge transfer—communicating innovative findings in teaching (redirecting curriculum); change of values within science faculties; and structured implementation and well-coordinated planning of the transformation (establishment of a ‘transition unit’). Specific strategies for implementing these four areas are outlined. In addition, we discuss why the replacement of animal testing should be an essential goal for universities, why this goal has not yet been achieved, and why concerted efforts toward change are required.Item Editorial for special issue(LEOH - Journal of Animal Law Ethics and One Health, 2025) Deckha, ManeeshaAnimal experimentation has long been a topic of bioethical, philosphical, and legal debate.1 The vast majority of argumentation against the practice proceeds through deontological and utilitarian premises that may be characterized as largely liberal in theoretical orientation.2 These accounts highlight harms to animals through a methodology of rational argumentation and with a substantive focus on the interests of animals. Argumentation against experimenting on animals rooted in critical theoretical perspectives, i.e. theories that challenge or supplement these classic liberal theories such as ecofeminist and feminist care approaches,3 are considerably less prominent in the scholarship contesting animal experimentation.4Item A child’s right to non-anthropocentric education(VerfBlog, 2025) Deckha, ManeeshaThe European Charter on Fundamental Human Rights (“the Charter”) is not concerned about the core topic of contemporary animal law: animal rights. But although the Charter is silentabout animals, it is possible to connect certain human rights it enshrines to animals in amanner that can foment animal rights. The protection of a healthy environment in Article 37 is an obvious choice inasmuch it is backed up by Article 191 of the Treaty on the Functioning of the European Union (TFEU) and the European Green Deal’s commitment to net zero greenhouse gas emissions by 2050. Indeed, there is a growing body of work aimed at harnessing environmental support for the rights of nature in favour of animal rights. In this contribution, I want to suggest a lesser theorized human right in the Charter that similarly has considerable potential to benefit animals: the right to education under Article 14.Item Taxonomic utility of isolated ankylosaurian dinosaur teeth using traditional and geometric morphometrics with implications for ankylosaur paleoecology(Journal of Paleontology, 2025) Cross, Emily; Fraass, Andrew J.; Arbour, Victoria M.The presence of a basal cingulum, fluting, and overall size have been used to differentiate nodosaurid and ankylosaurid teeth for decades. The taxonomic utility of tooth morphology in ankylosaurs, however, has not been quantitatively tested. In addition, new phylogenetic hypotheses recognize four ankylosaur families (Panoplosauridae, Polacanthidae, Struthiosauridae, and Ankylosauridae), rather than the traditional nodosaurid–ankylosaurid dichotomy. Understanding ankylosaur tooth variation could better help identify taxa with ambiguous phylogenetic affinities or allow isolated teeth to test paleoecological questions such as a potential extirpation of mid-Cretaceous ankylosaurids from Laramidia. We analyzed a large sample of ankylosaur teeth using traditional and geometric morphometrics and investigated the utility of size and the presence of a cingulum and fluting for differentiating ankylosaur teeth. Morphometric analyses show that “nodosaurids” had the greatest variation in tooth shape and size. Panoplosauridae and Struthiosauridae account for a large amount of “nodosaurid” variation, whereas basal ankylosaurs, Polacanthidae, and Ankylosauridae share a similar restricted morphospace. Teeth with a crown base length or height over 10 mm are found only in panoplosaurids, struthiosaurids, and Peloroplites, but smaller sizes are found in all clades. A basal cingulum and fluting are associated with Ankylosauridae and Panoplosauridae. Linear discriminant analyses could accurately identify only between 50% and 75% of the teeth in our sample; thus, they should be used in conjunction with size and discrete traits when identifying isolated teeth. With these findings, caution should be used when attempting to use isolated ankylosaur teeth in broader paleoecological questions, and reclassification of museum collections should be undertaken.Item Record of foraminifera test composition throughout the Phanerozoic(Proceedings of the Royal Society B Biological Sciences, 2025) Faulkner, Katherine; Lowery, Christopher; Martindale, Rowan Claire; Simpson, Carl; Fraass, Andrew J.Marine calcifiers produce calcareous structures (e.g. shells, skeletons or tests) and are therefore sensitive to ocean chemistry. Nevertheless, the long-term evolutionary consequences of marine carbonate changes are not well understood. This article compares calcareous and non-calcareous responses to ocean chemistry changes throughout the Phanerozoic Eon (541 million years ago to present). To accomplish this, we calculated proportional wall-type diversity, origination rates and extinction rates for 2282 benthic foraminiferal genera. Calcareous origination and extinction rates fluctuated throughout the Palaeozoic Era (541–251.9 million years ago), but during the Mesozoic Era (251.9–66 million years ago), calcareous origination and extinction rates stabilized following the evolution of pelagic calcifiers. Despite variations in Cenozoic Era (66–0 million years ago) foraminifera diversity, calcareous wall types maintained around 77% proportional diversity. Although calcareous wall-type extinction rates decline during the Mesozoic and Cenozoic, Phanerozoic foraminifera wall-type changes during individual events are largely contingent upon contemporaneous conditions rather than overarching trends. Of the Big Five mass extinction events, calcareous wall-type proportions only decreased at the end-Permian (73% to 26% diversity) and end-Triassic (56% to 50% diversity). These results suggest long-term ocean chemistry changes were not the main driver of foraminiferal wall-type diversity through time.Item Canadian natural science graduate stipends lie below the poverty line(PLoS ONE, 2025) Fraass, Andrew J.; Bailey, Thomas J.; Karunakumar, Kayona; Wishart, Andrea E.Despite the critical role of graduate students in the Canadian research ecosystem, students report high levels of financial stress. As a case study, we collected graduate minimum stipends and tuition data from all university graduate programs in Canada in Ecological Sciences/Biology and Physics, along with cost of living measures for the cities in which they reside. These data are heterogeneous, complex, and in many cases simply not publicly available, making it challenging for potential graduate students to understand what support they should expect. We find Canadian minimum stipends are at values almost exclusively below the poverty threshold. Only two of 140 degree programs offered stipends which meet cost of living measures after subtracting tuition and fees. For graduate programs which offered a minimum guaranteed stipend, the average minimum domestic stipend is short ~Can$9,584 (international ~Can$16,953) of the poverty threshold after accounting for payment of tuition and fees. On average, approximately 33% of a minimum stipend is returned to the university in tuition and fees by a domestic Canadian student and 76% (59% median) by an international student, though there are important caveats with the international student comparison. While international comparison is difficult, the highest Canadian minimum stipend found is roughly equivalent or lower than the lowest stipend within the largest dataset of United States of America (US) Biology stipends, and lower than the United Kingdom (UK) stipend. University endowment correlates with minimum stipend amount but intra- and inter-institutional differences suggest it is not solely institutional wealth associated with graduate pay. We observe Canada is behind comparable countries in minimum funding levels for the next generation of scientists.