University of Prince Edward Island

Abstract Hydrogen is widely recognized as an essential element in achieving a net‐zero economy; however, the majority of global hydrogen production relies heavily on fossil fuels and employs highly polluting production techniques. Consequently, to meet the global targets of reducing fossil fuel consumption and lower greenhouse gas emissions, hydrogen production from renewable and clean resources, including biomass and water, has attracted considerable attention. In this context, this review discusses the recent technological advancements in thermochemical conversion (gasification and supercritical water gasification) and biological conversion (dark fermentation and photo‐fermentation) of biomass, as well as chemical conversion (photocatalytic water splitting). This review also highlights the technical challenges and barriers faced by each hydrogen production technique and offers new insights into the selection of highly effective and suitable hydrogen production methods from biomass and its derived waste and from water.

Increasing awareness of the environmental issues associated with conventional surfactants has incentivized the chemical industry to develop more sustainable alternatives such as biosurfactants, which are a class of surface-active molecules produced by microorganisms. Biosurfactants are environmentally benign and have the potential to be manufactured sustainably through microbial fermentations fed by renewable feedstocks, unlike conventional surfactants produced from petrochemical feedstocks. Biosurfactants therefore have an important role in the development of sustainable surfactants for consumer and industrial use. To identify new biosurfactants, we screened a microbial library for strains producing emulsifiers. Analysis of active microbial extracts by UHPLC-HRMS led to the identification of the variovoracins, a new class of glycolipopeptide biosurfactants, from Variovorax paradoxus RKNM0096. Their chemical structures were elucidated by NMR spectroscopy, and the absolute configuration was determined through multiple chiral derivatization techniques. Meanwhile, tandem mass spectrometry revealed the presence of numerous homologues differing in the position of the C8 or C12 acyl chain. Genome sequencing and bioinformatic analysis identified a candidate biosynthetic gene cluster (BGC) whose role in variovoracin biosynthesis was confirmed by functional characterization of a key rhamnosyltransferase, which was shown to efficiently convert a mono-rhamnosylated pathway intermediate to the final di-rhamnosylated variovoracin. Genome mining identified 123 BGCs homologous to the variovoracin cluster distributed in 12 genera within the Pseudomonadota, but concentrated within the Variovorax genus. Production of variovoracin analogues was demonstrated in two strains predicted to produce mono-rhamnosylated congeners, further validating the assignment of the variovoracin BGC. Despite their structural similarity to the rhamnolipids, the characteristic curvature (Cc) of the variovoracins has the opposite sign, indicating that their non-ionic and hydrophobic properties confer unique functional characteristics and consequently different surfactant applications.

Turbidity is increasing in freshwaters globally due to human activities and is known to affect visually-mediated behaviours in fish. As anthropogenic impacts continue to degrade aquatic environments, it is critical to determine how sensory systems are affected and what this might mean for population persistence. We investigated visual morphology and opsin gene expression in an African cichlid fish (Pseudocrenilabrus multicolor) that experiences environmental extremes across its East African range. We examined visual morphology (i.e., size of eyes and brain) and quantified retinal opsin gene expression of adult wild-caught fish from two sites representing extremes of turbidity and oxygen (a high turbidity, high dissolved oxygen river and a low turbidity, low dissolved oxygen swamp). Further, we reared offspring of wild-caught parents from each population in a full-factorial high/low oxygen, high/low turbidity design to test for plasticity and tease apart the influence of each stressor individually and in combination. For wild-caught fish, population drove variation in eye morphology and brain mass such that the river population had larger visual traits than the swamp population. Sex was an important driver for brain morphology with males having larger brains and optic tecta than females. All fish expressed the same cone opsin palette, comprised of sws2a, rh2a, and lws; however, river fish expressed a higher proportion of lws opsin compared to swamp fish. Further, population significantly explained variation in lws opsin for males and trended toward significance in females. When major environmental stressors were examined in the rearing experiment, oxygen was a strong driver of eye and brain size. Cone opsin trends were less clear in the rearing experiment; the proportion of lws opsin in females significantly varied by the interactive effect of oxygen and turbidity, while sws2a opsin in males varied significantly by turbidity. This research improves our understanding of the effect of elevated turbidity on African cichlid vision and contributes to growing knowledge of how animals respond to human-induced environmental change and multiple stressors.

To determine the effect of warm-up on the performance of laparoscopic ovariectomy (LOVE) on a live dog by veterinary medical students. Randomized experimental, post-test only, control group design. A total of 15 fourth-year veterinary students with prior training in basic laparoscopy. Participants were randomly assigned to Group NW (n = 8), who did no warm-up, or Group W (n = 7), who engaged in a 30-min preoperative warm-up using a laparoscopic simulator and a laparoscopic video game (Underground). Laparoscopic surgical procedures were video-recorded and evaluated by a blinded board-certified surgeon (MF). The duration of surgery was recorded, and the student's performance was scored using a previously validated rubric. Outcomes were compared between groups with two-sample t-tests. The a priori significance was set to 0.05 (α = 0.05). The duration of surgery was 20 min less in Group W (M = 63; range: 58-86) compared to Group NW (M = 84; range: 58-86; ). Students in Group W achieved higher scores (M = 138.4; range: 122-152) than those in Group NW (M = 121.5; range: 106-130; ). Veterinary students who did warm-up on a laparoscopic simulator and laparoscopic video game just before LOVE effectively decreased surgical time and increased efficiency. This study is consistent with the findings in human medicine, supports the use of warm-up exercises in surgical trainee programs before performing laparoscopic surgeries on live animals.

Our research topic brings together four studies that explore different aspects of this challenge by adopting a comprehensive approach to companion animal behavioral management. In this collection, Sonowal et al. (2025) compared scented and non-scented chew toys to evaluate their effect on chewing and mouthing behaviors in puppies, which are among the most common developmental issues faced by caregivers during critical bonding periods. Although these behaviors are largely normal communicatory and exploratory behaviors, they are frequently reported as problematic and can strain the human-animal bond at a sensitive stage of development. Authors showed that sensory enhanced toys significantly increased puppy engagement and reduced the need for caregiver prompting during observed sessions. Interestingly, while the frequency of unwanted chewing did not change over the course of the intervention, caregivers reported perceiving mouthing as less problematic. This finding highlights the importance of how caregivers experience and interpret behavior when managing behavioral problems in companion animals and offers a valuable insight for veterinary behavioral medicine regarding the key role of caregiver perspectives.Distinguishing primary behavioral disorders from those arising secondary to medical conditions such as pain is one of the most challenging areas in behavioral medicine and was addressed by Kwik et al. (2025) within our research topic. Their case series revealed that maladaptive pain was present in 70% of dogs referred for behavioral complaints when assessed using a multimodal approach. This finding carries important implications for clinical practice and raises important questions such as: "How often are animals diagnosed with behavioral problems before pain is thoroughly investigated?" and "How frequently do behavior modification efforts fail because an underlying pain remains untreated?". Their study demonstrates that multimodal treatment addressing both pain and behavior led to recovery in most cases, which highlights the inseparable relationship between medical and behavioral assessment. It further underscores the significant welfare consequences of diagnostic delay, resulting in unnecessary animal suffering and caregiver distress.Feline behavioral management is the focus of two interesting studies in this collection. In order to better understand undesired scratching in domestic cats, Salgirli Demirbas et al. (2024) employed a multifactorial approach and identified the risk factors that contribute to this behavior. Their findings provide valuable insight into the environmental, social and individual factors that influence when normal feline behavior becomes problematic in the domestic setting. They identified stress as a leading contributor to undesired scratching, with specific risk factors including the presence of children in the household, high levels of play and nocturnal activity as well as personality traits such as aggression or disruptiveness. The authors emphasize that scratching, while a normal species-typical behavior, becomes problematic when underlying stressors are not adequately addressed. This etiological perspective is complemented by the Endersby et al. (2024), who present a largescale, controlled evaluation of a pheromone-impregnated collar for the management of multiple feline behavioral problems. With nearly 500 cats included, the findings provide robust evidence that continuous pheromone delivery can significantly reduce behavioral problems such as inappropriate urination, destructive scratching and inter-cat conflict, with trends toward improvement in fear-related behaviors. These results are particularly important, as these behaviors are among the most commonly reported problems in the companion cat population and represent predominant reasons for relinquishment and, in some cases, euthanasia. Their study highlights the value of pheromonal signals in reducing stress by promoting emotional stability in cats and demonstrates how effective pheromone messaging can be in managing a range of behavioral problems.Collectively, the studies in this Research Topic highlight a number of fundamental concepts that deserve to be included into standard clinical practice. These include the critical importance of systematic pain assessment in cases presenting with behavioral change; recognition that caregiver perceptions and expectations may be influential determinants of treatment success and must be addressed; the value of identifying risk factors to inform management strategies and the role of sensory modulation as a foundational strategy for supporting emotional well-being of companion animals. This collection supports the view that advancing the field requires moving beyond simplistic approaches toward integrative frameworks and adaptive expectations, with evidencebased strategies that enhance quality of life and strengthen the human-animal bond.

Live Well PEI provides individuals and organizations in PEI with information and tools to support healthy behaviours. This paper describes the development of the Live Well PEI community-mobilization intervention, consisting of a website and integrated community granting program for health promotion initiatives. (1) What is an effective design of a web-based community-mobilization intervention for community-led health promotion and (2) what lessons can be learned and shared for community-engaged, evidence-informed public health intervention development? Intervention development followed the Six Steps in Quality Intervention Development (6SQuID) process. Through literature reviews, jurisdictional scans, expert consultations, and community engagement, evidence for conditions that foster community mobilization was gathered and used to inform development of intervention components. The intervention was refined through iterative expert and community consultations. Four conditions that foster community-led health promotion were identified: accessibility of grant funding, availability of community data, resources to enhance capacity, and community collaboration. These conditions informed outputs of a Theory of Change. Intervention design that supports these conditions included website elements such as collections of evidence-informed health promotion interventions, stories of prior community-led projects, and community health status and needs information. The granting program integrates research and community feedback on project eligibility, grant administration and support for awardees. Findings from an evaluability assessment support pilot-testing implementation of the intervention. Development of the community-mobilization intervention provides a prime case example of evidence-informed, community-engaged public health intervention co-design. Learnings are applicable to community-focused health promotion initiatives across Canada.

Quantifying and mapping material stocks is crucial for built environment stock management and sustainable planning. This study presents a Geographic Information System (GIS)-based bottom-up approach for modelling road and building material stocks in Grenada, a small island state. Light Detection and Ranging (LiDAR) data were utilized to estimate building heights and building stocks. The first 3D WebGIS application was developed for Grenada to visualize material stocks in 3D city models. The road stocks in Grenada were estimated to be 4375 kilo tonnes (40.96 t/capita) in 2015, about one-third of building stocks, highlighting the importance of infrastructure stocks in small island states. LiDAR-derived building heights were more accurate, estimating building stocks 4.8 % lower than occupancy class-based height assumptions in the sample site. This study develops Grenada’s first road stock account and assesses a novel methodology for estimating building stocks in small island states, offering insights for enhancing resource assessment and management.