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The vertebrate bone hypothesis: Understanding the impact of bone on vertebrate stoichiometry
No full text1. Understanding how animals store and recycle nutrients is a major question in ecological stoichiometry, a field that applies mass-balance to ecological and physiological processes. However, ecological stoichiometry has thus far failed to accurately predict elemental demand and release in vertebrates.
2. Because they invest in bone, a tissue mineralized with calcium phosphate, vertebrates are phosphorus (P) rich, allowing them to uniquely impact P cycling. Nonetheless, bone's impact goes further than merely changing vertebrate body elemental content.
3. We propose a potential guiding hypothesis for vertebrate P stoichiometry called the ‘Vertebrate Bone Hypothesis (VBH)’. The VBH has three components: (1)Bone strongly impacts vertebrate whole-body %P and N:P. (2) Bone is a P storage tissue that acts in elemental homeostasis. (3)Bone does not have constant elemental content.
4. To characterize this hypothesis, we integrate bone physiology with stoichiometric principles, and we systematically review quantitative bone measurements to showcase cryptic diversity in vertebrate P content.
5. Finally, we apply the characteristics of the VBH to ontogeny and reproduction, both of which impact bone physiology and elemental demand, to demonstrate the context dependency of bone's stoichiometric impact.Our work is supported by NSERC and the University of Victoria.FacultyReviewe
Associations between stress, affect, and physical activity in young adulthood: Stages of change as potential moderators
No full textCurrent global estimates of physical activity suggest that less than 20% of adolescents are sufficiently physically active, and 28% of adults over 18 are not active enough to stay healthy despite the known physical and mental health benefits. Given the notable short- and long-term benefits of physical activity, paired with insufficient engagement rates, young adulthood (ages 19-25) is a critical time to build and support continued physical activity engagement across the lifespan. Research has identified increased stress and negative mood to impair physical activity efforts, but the associations between stress and affect and physical activity at the daily levels remained largely unexplored. In addition, potential moderating factors of these associations currently lack research. This study aimed to understand the associations between daily stress, positive and negative affect, and physical activity, as well as explore the six Stages of Change (SoC) as potential moderating factors. Undergraduates (N = 74; Mage = 20.88, SD = 2.53) responded to surveys administered through a smartphone app for 14 days and wore a Fitbit Charge 2 to gather physical activity data (i.e., daily steps). Multi-level models showed no within-person associations between stress, positive and negative affect, and physical activity. However, two significant interactions were observed: (1) contemplation significantly moderated the association between positive affect and physical activity, and (2) action significantly moderated the association between negative affect and action. Overall, results concerning the moderating impact of SoC were mixed; yet provide directions for future research. Results can provide new insight for strategies that focus on strengthening personal intentions and promoting individual motivations to engage in health behaviours such as physical activity.Graduat
Adolecent wilderness therapy: The relationship of client outcomes to reasons for referral, motivation for change, and clinical measures
No full textThe study was conducted in accordance with the Declaration of Helsinki and approved by the Institutional Review Board at the University of Victoria (protocol #18-169, 03.05.2018) for studies involving humans.
Archival and anonymized data was accessed through the Outdoor Behavioral Healthcare Research Centre and provided to the research team with no identifying details of clients.
The authors do not have permission to share data. Data inquiries should be directed to Outdoor Behavioral Healthcare Research Center.Outdoor behavioral healthcare is a specific model and industry utilizing wilderness therapy (WT), a residential treatment approach comprised of outdoor travel and living for youth experiencing mental health, substance use, and behavioral concerns. We present data from 6417 participants about reasons for referral, admission, and discharge scores from the Youth-Outcome Questionnaire (Y-OQ), youth interest and commitment to treatment, reliable change scores, and the relationship between these variables. One-third of youth entered WT with sub-clinical scores, varying levels of client motivation and voluntariness in relation to clinical outcomes, a diverse range of presenting problems without clear indication of specialized treatment planning, and differing responses to treatment by referral reason. Identifying those not responding to WT and those at risk of deterioration from the time of admission requires further investigation to improve client outcomes for this treatment modality. Recommendations include placing increased importance on accurate and thorough screening and assessment, utilizing baseline and routine outcome monitoring, reducing coercion, and considering specialized intervention.FacultyReviewe
Governing oil or governed by oil? Discourses of oil in Newfoundland & Labrador politics
Get PDFAs an energy-producing province, the oil industry is a significant part of Newfoundland and Labrador's politics, development, and identity. This research investigates the role oil has played in discourses of Newfoundland and Labrador politics. Drawing on existing literature, I reviewed and coded findings using NVivo from 528 provincial transcripts. Through this inductive coding strategy, various themes emerged in the discourses of oil in Newfoundland politics. Themes included; a contention between resources, resource nationalism, and emotional sentiment towards the oil industry. These findings create opportunities for future comparative analysis between energy-producing provinces and fit into the existing literature of petropolitics and discourse related to oil in Canada and regional politics.Valerie Kuehne Undergraduate Research Awards (VKURA)UndergraduateReviewe
UVic Convocation June 10, 2024 – 10:00 am
No full textStudents from the faculties of Graduate Studies, Gustavson School of Business and Education.UndergraduateUnreviewe
Framing reciprocal contributions across Indigenous and artisanal fisheries: Exploring cases, conflicts, and future pathways
No full textThroughout human history, Indigenous and local communities have been stewards of nature. Their practices often embody the value of reciprocity, fostering positive contributions of humans with other components of nature. Yet, during colonization, and more specifically with the rise of neoliberal policies and the dominance of market worldviews, we have become distanced from this nature-people reciprocity. Concepts like "ecosystem services" provide a framework for comprehending the vital functions that ecosystems play in many facets of human existence. However, they also inadvertently narrow the discourse to a unidirectional relationship: nature serving people. This perspective can obscure our responsibilities to care for and sustain the environment. In this dissertation, I unpack the nature-people reciprocity, exploring its theoretical and practical relevance for social-ecological systems. I frame this work in one of the oldest biocultural interactions: marine fishing practices. This dissertation has five chapters. In the introductory Chapter, I outline the rationale and objectives of the study, highlighting the gaps in current understandings of nature-people reciprocity. In the second Chapter, I introduce the concept of “reciprocal contributions,” which encompasses actions, interactions, and experiences between people and other components of nature that result in positive contributions and feedbacks that accrue to both directly or indirectly across different dimensions and levels (Chapter 2). Following this conceptual chapter, I draw on two case studies to understand how reciprocal contributions can emerge with a bi-hemispherical approach in diverse fishing settings. First, in Haida Gwaii (North America), I partnered with the Council of Haida Nation, Haida Fisheries, to research the ancestral relationships between Haidas and abalone, examining their reciprocal contributions. Here, I interviewed Haida knowledge holders who have lived through the tragedy of the commercial abalone fishing boom and subsequent decline. In this chapter, I discuss the harms of overfishing on reciprocal contributions to review the past and rethink future abalone management strategies (Chapter 3). Second, working with artisanal fishers in Patagonia (South America), I investigated the reciprocal contributions between these individuals and marine life, especially seabirds. Employing both ethnographic and ecological methodologies, I explore the intricate relationships between fishers and seabirds and discuss how these reciprocal contributions can serve as tools for studying the complex interactions between humans and nature within an ecosystem-based management framework (Chapter 4). In the concluding Chapter, I reflect on the theoretical and practical implications of reciprocal contributions through the themes of nature-people relationships and fisheries management. Ultimately, I hope that this dissertation serves as work to resituate the importance of reciprocity.Graduat
Certain new applications of symmetric q-calculus for new subclasses of multivalent functions associated with the cardioid domain
No full textIn this work, we study some new applications of symmetric quantum calculus in the field of Geometric Function Theory. We use the cardioid domain and the symmetric quantum difference operator to generate new classes of multivalent q-starlike and q-convex functions. We examine a wide range of interesting properties for functions that can be classified into these newly defined classes, such as estimates for the bounds for the first two coefficients, Fekete–Szego-type functional and coefficient inequalities. All the results found in this research are sharp. A number of well-known corollaries are additionally taken into consideration to show how the findings of this research relate to those of earlier studies.The research work of Fairouz Tchier is supported by the project number RSP2024R401, King Saud University, Riyadh, Saudi Arabia.FacultyReviewe
Therapeutic drug monitoring of clozapine in human serum by high-throughput paper spray mass spectrometry
Get PDFThe authors acknowledge the University of Victoria and Vancouver Island University for their ongoing support of our research and students. We thank Thermo Fisher Scientific for providing the instrument used in this study and for ongoing technical support, and LifeLabs Medical Laboratories for their research collaborations and for providing the anonymous patient samples that enabled this study. The authors are publishing this work in memory of the lead author Armin Saatchi, who passed away suddenly during the preparation of this manuscript. All who knew him will miss his tireless enthusiasm and impeccable research ethics. We dedicate this work to his memory.Introduction:
Monitoring the atypical antipsychotic drug clozapine is crucial to ensure patient safety. This article showcases a high-throughput analytical method for measuring clozapine and its primary metabolite norclozapine (N-desmethylclozapine) in serum using paper spray mass spectrometry (PS-MS).
Objectives:
This study aimed to assess the viability of a PS-MS method for the rapid measurement of clozapine and norclozapine in human serum samples as an alternative to liquid chromatography mass spectrometry (LC-MS).
Methods:
Serum samples were processed by protein precipitation followed by deposition of the supernatant containing labelled internal standards onto paper spray substrates mounted in cartridges. Analytes were then analyzed using a triple quadrupole mass spectrometer equipped with a commercial paper spray ionization source. The results obtained from the patient samples were compared to those from a validated LC-MS assay.
Results:
PS-MS calibrations for clozapine and norclozapine were linear (R2 > 0.99) over five days. Between-run precision was below 8 %, and within-run precision did not exceed 10 %. When compared to a validated LC-MS method, the mean bias for 39 patient samples was −9% for clozapine and −1% for norclozapine, with no outliers. Mass spectrometry ion ratio comparisons indicated no interference for patient samples above the lower limit of quantification. There was less than 7 % change in the measured concentrations of both analytes over five days for samples dried on paper substrates. Notably, virtually no maintenance of the MS source was required during this study.
Conclusion:
This study illustrates the potential of PS-MS for serum drug monitoring in the clinical laboratory.This work was supported by the Natural Science and Engineering Research Council of Canada (NSERC) Discovery Grant Program funding (RGPIN-2021-02981).FacultyReviewe
Label-free study of Bovine Serum Albumin conformational dynamics using optical nanotweezers and experimental analysis of asymmetric DNH nanostructures
Get PDFThis thesis concerns the label-free investigation of Bovine Serum Albumin (BSA) conformational dynamics and the interaction of different proteins with gold surfaces using Double Nanohole(DNH) optical tweezers. It is divided into two parts: Study of conformational changes of labeled and unlabelled BSA and investigation of electrostatic interactions between proteins and gold surfaces. The Gibbs energy for the N to F states was calculated for both labeled and unlabelled BSA from the free energy diagram and the values show a small effect of labeling on the protein. This Chapter also explored the effect of electrostatic interactions between the gold surface and proteins with different charges on the trapping stiffness. Further, the experimental investigation of the development of a new nanostructure called Asymmetric Double Nanohole and its possible application in optical trapping are described in this thesis. Fabrication techniques and result analysis are described, even though the trapping efficiency turned out to be the same as that for traditional DNH structures.Graduat
An interspecific foraging association with polar bears increases foraging opportunities for avian predators in a declining Arctic seabird colony
Get PDFInterspecific foraging associations (IFAs) are biological interactions where two or more species forage in association with each other. Climate-induced reductions in Arctic sea ice have increased polar bear (Ursus maritimus) foraging in seabird colonies, which creates foraging opportunities for avian predators. We used drone video of bears foraging within a common eider (Somateria mollissima) colony on East Bay Island (Nunavut, Canada) in 2017 to investigate herring gull (Larus argentatus) foraging in association with bears. We recorded nest visitation by gulls following n = 193 eider flushing events from nests during incubation. The probability of gulls visiting eider nests increased with higher number of gulls present (β = 0.14 ± 0.03 [SE], p < .001) and for nests previously visited by a bear (β = 1.14 ± 0.49 [SE], p < .02). In our model examining the probability of gulls consuming eggs from nests, we failed to detect statistically significant effects for the number of gulls present (β = 0.09 ± 0.05 [SE], p < .07) or for nests previously visited by a bear (β = −0.92 ± 0.71 [SE], p < .19). Gulls preferred to visit nests behind bears (χ2 = 18, df = 1, p < .0001), indicating gulls are risk averse in the presence of polar bears. Our study provides novel insights on an Arctic IFA, and we present evidence that gulls capitalize on nests made available due to disturbance associated with foraging bears, as eiders disturbed off their nest allow gulls easier access to eggs. We suggest the IFA between gulls and polar bears is parasitic, as gulls are consuming terrestrial resources which would have eventually been consumed by bears. This finding has implications for estimating the energetic contribution of bird eggs to polar bear summer diets in that the total number of available clutches to consume may be reduced due to avian predators.Environment and Climate Change Canada, the University of Windsor, Mitacs Accelerate Cluster grant (in collaboration with Baffinland Iron Mines), and the Natural Sciences and Engineering Council (NSERC) generously provided funding for this project.FacultyReviewe