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Abstract Human alveolar echinococcosis is increasingly documented in Alberta, Canada. Its causative agent, Echinococcus multilocularis (Em), can be transmitted to humans by infected dogs. We assessed the prevalence and associated risk factors for Em infections in domestic dogs in Calgary, Alberta, Canada. In this cross-sectional study that coupled collection and assessment of dog feces with a survey on potential risk factors, 13 of 696 (Bayesian true prevalence, 2.4%; 95% CrI: 1.3–4.0%) individual dogs’ feces collected during August and September 2012 were qPCR positive for Em. Sequencing two of these cases indicated that both were from the same Em European strain responsible for human infections in Alberta. Likelihood of intestinal Em was 5.6-times higher in hounds than other breeds, 4.6-times higher in dogs leashed at dog parks than those allowed off-leash, 3.1-times higher in dogs often kept in the backyard during spring and summer months than those rarely in the yard, and 3.3-times higher in dogs living in neighbourhoods bordering Bowmont park than those in other areas of Calgary. This situation warrants surveillance of dog infections as a preventative measure to reduce infections in North America.

Livestock have been and continue to be an important part of the agricultural landscape in North America. Research on how to mitigate livestock predation by North American carnivores developed quickly during the 20th century. We collected information on 75 field-based experiments published since 1970 that evaluated strategies to mitigate livestock predation by wolves and coyotes. Collected research came from journal articles and grey literature, and we identified 22 mitigation strategies. We developed a ‘robustness index’ to compare each experiment based on its empirical design, temporal/spatial coverage, and sample size. We found the robustness index values increased over time, particularly for lethal mitigation strategies. Overall robustness of research on lethal mitigation strategies was similar to the robustness of research on non-lethal mitigation strategies. Some strategies were not well evaluated as 12 of the 22 mitigation strategies were evaluated only once or twice; some common lethal mitigation strategies (e.g., shooting) were not formally evaluated until the 1990s. We identified some robust assessments of mitigation strategies that reported positive effects (e.g., predator sterilization, protection llamas). In some cases, these were the only evaluation or the only robust evaluation of a strategy. In the few cases where there were multiple robust assessments for a single strategy, the outcomes were inconsistent. No strategies evaluated more than once had consistently high robustness index values and positive outcomes. Importantly, older practices based on less robust research should be re-evaluated or discarded.

Abstract Purpose Various surgical treatments have been described for the treatment of reverse Hill–Sachs lesions (rHSls) sized between 20% and 50% in the case of posterior shoulder dislocation. The aim of this systematic review is to report the clinical and radiological outcomes of subscapularis or lesser tuberosity transfer (McLaughlin and modified procedures) compared to bone or osteochondral autograft or allograft. Methods A systematic review was performed on five medical databases up to December 2022. The inclusion criteria were clinical studies of all levels of evidence describing clinical or radiological outcomes of either procedure. The assessment of the quality of evidence was performed with the Modified Coleman Score. Results A total of 14 studies (five prospective and nine retrospective) were included. A total of 153 patients (155 shoulders, 78.4% male) with a mean age of 37.2 (22–79) years were reviewed at an average follow‐up of 53.1 (7.1–294) months. No relevant difference was found for the clinical scores, range of motion, complications and redislocation rate between the two treatments. Radiological osteoarthritis (OA) was reported in 11% (10/87) in the McLaughlin group and in 21% (16/73) in the humeral reconstruction group. Conclusions McLaughlin and anatomic humeral reconstruction lead to similar satisfactory clinical results and a low redislocation rate in the treatment of rHSls. Anatomic humeral reconstruction seems associated with an increased risk of OA progression. Level of Evidence Level IV.

Abstract Background Development of large single nucleotide polymorphism (SNP) arrays can make genomic data promptly available for conservation problematic. Medium and high-density panels can be designed with sufficient coverage to offer a genome-wide perspective and the generated genotypes can be used to assess different genetic metrics related to population structure, relatedness, or inbreeding. SNP genotyping could also permit sexing samples with unknown associated metadata as it is often the case when using non-invasive sampling methods favored for endangered species. Genome sequencing of wild species provides the necessary information to design such SNP arrays. We report here the development of a SNP-array for endangered Rangifer tarandus using a multi-platform sequencing approach from animals found in diverse populations representing the entire circumpolar distribution of the species. Results From a very large comprehensive catalog of SNPs detected over the entire sample set (N = 894), a total of 63,336 SNPs were selected. SNP selection accounted for SNPs evenly distributed across the entire genome (~ every 50Kb) with known minor alleles across populations world-wide. In addition, a subset of SNPs was selected to represent rare and local alleles found in Eastern Canada which could be used for ecotype and population assignments - information urgently needed for conservation planning. In addition, heterozygosity from SNPs located in the X-chromosome and genotyping call-rate of SNPs located into the SRY gene of the Y-chromosome yielded an accurate and robust sexing assessment. All SNPs were validated using a high-throughput SNP-genotyping chip. Conclusion This design is now integrated into the first genome-wide commercially available genotyping platform for Rangifer tarandus. This platform would pave the way to future genomic investigation of populations for this endangered species, including estimation of genetic diversity parameters, population assignments, as well as animal sexing from genetic SNP data for non-invasive samples.

Abstract Protected areas are important in species conservation, but high rates of human-caused mortality outside their borders and increasing popularity for recreation can negatively affect wildlife populations. We quantified wolverine (Gulo gulo) population trends from 2011 to 2020 in > 14,000 km2 protected and non-protected habitat in southwestern Canada. We conducted wolverine and multi-species surveys using non-invasive DNA and remote camera-based methods. We developed Bayesian integrated models combining spatial capture-recapture data of marked and unmarked individuals with occupancy data. Wolverine density and occupancy declined by 39%, with an annual population growth rate of 0.925. Density within protected areas was 3 times higher than outside and declined between 2011 (3.6 wolverines/1000 km2) and 2020 (2.1 wolverines/1000 km2). Wolverine density and detection probability increased with snow cover and decreased near development. Detection probability also decreased with human recreational activity. The annual harvest rate of ≥ 13% was above the maximum sustainable rate. We conclude that humans negatively affected the population through direct mortality, sub-lethal effects and habitat impacts. Our study exemplifies the need to monitor population trends for species at risk—within and between protected areas—as steep declines can occur unnoticed if key conservation concerns are not identified and addressed.

Abstract Genetic diversity is theorized to decrease in populations closer to a species' range edge, where habitat may be suboptimal. Generalist species capable of long‐range dispersal may maintain sufficient gene flow to counteract this, though the presence of significant barriers to dispersal (e.g., large water bodies, human‐dominated landscapes) may still lead to, and exacerbate, the edge effect. We used microsatellite data for 2421 gray wolves (Canis lupus) from 24 subpopulations (groups) to model how allelic richness and expected heterozygosity varied with mainland–island position and two measures of range edge (latitude and distance from range center) across >7.3 million km2 of northern North America. We expected low genetic diversity both at high latitudes, due to harsh environmental conditions, and on islands, but no change in diversity with distance to the range center due to the species' exceptional dispersal ability and favorable conditions in far eastern and western habitats. We found that allelic richness and expected heterozygosity of island groups were measurably less than that of mainland groups, and that these differences increased with the island's distance to the species' range center in the study area. Our results demonstrate how multiple axes of geographic isolation (distance from range center and island habitation) can act synergistically to erode the genetic diversity of wide‐ranging terrestrial vertebrate populations despite the counteracting influence of long‐range dispersal ability. These findings emphasize how geographic isolation is a potential threat to the genetic diversity and viability of terrestrial vertebrate populations even among species capable of long‐range dispersal.

Abstract Species at the periphery of their range are typically limited in density by poor habitat quality. As a result, the central–marginal hypothesis (CMH) predicts a decline in genetic diversity of populations toward the periphery of a species' range. Grizzly bears (Ursus arctos) once ranged throughout most of North America but have been extirpated from nearly half of their former range, mainly in the south. They are considered a species at risk even in Canada's remote North, where they occupy the northernmost edge of the species' continental distribution in a low‐productivity tundra environment. With climate change, one of their main prey species in the tundra (caribou), which has always shown yearly fluctuations, is declining, but simultaneously, grizzlies appear to be expanding their range northward in the same tundra environment. Yet, a lack of population density estimates across the North is hindering effective conservation action. The CMH has implications for the viability of peripheral populations, and the links between population fluctuations, potential bottlenecks, and genetic diversity need to be determined to contribute to species' conservation. Using noninvasive genetic sampling from 2012 to 2014 and autosomal DNA genotyping (via microsatellites), we estimated bear density using a spatial capture–recapture framework and analyzed genetic diversity using observed heterozygosity (Ho), allelic richness (AR), and expected heterozygosity (He). We compared our findings to other studies that used comparable methodologies on grizzly bears and a related species (black bears; Ursus americanus). We found densities of grizzly bears that were low for the species but characteristic for the region (5.9 ± 0.4 bears/1000 km2), but with high Ho (0.81 ± 0.05), AR (7 ± 0.78), and He (0.71 ± 0.03), despite a signal of recent bottlenecks. In both species, peripherality was not correlated with Ho but was negatively correlated with density. We suggest that the apparent growth of this expanding population of grizzlies offsets the negative impacts of recent bottlenecks on Ho. Indigenous knowledge provides historical context (on the order of centuries, e.g., arctic large mammal fluctuations, grizzly bear bottlenecks) for the current bear population dynamics (on the order of decades, e.g., climate change, northern grizzly bear expansion).

Abstract Compact Ni−Rh alloys are electrodeposited potentiostatically on rotating disk and sheet electrodes; film compositions are adjusted by varying bath composition and deposition potential Edep. SEM images of these alloys show a compact, globular morphology for Rh contents up to 30 at%, and a smoother aspect for films with a medium‐to‐high content of Rh. XRD spectra show the formation of a single crystalline phase, with diffraction peaks in intermediate positions between those of the constituent elements. Data analysis indicates that crystal lattice parameters vary with composition according to Vegard's law. Linear voltammetries of nitrate reduction in alkali highlight a maximum of activity, in terms of reduction current, for alloys in the range of 10–30 at.% Rh. Prolonged electrolysis at appropriate potential performed with Ni85Rh15 alloy shows, in comparison with pure Ni and pure Rh: much increased activity and faster abatement of nitrate; lower production of the undesired nitrite species; higher selectivity towards production of ammonia.

Abstract Background Several migratory ungulates, including caribou, are dramatically declining. Caribou of the Barren-ground ecotype, which forms its own subspecies, are known to be mainly migratory. By contrast, within the Woodland subspecies, animals of the Boreal ecotype are known to be mainly sedentary, while those within the Northern and Central Mountain ecotypes to be partially migratory, with only some individuals migrating. Promotion of conservation actions (e.g., habitat protection) that are specific to both residents and migrants, as well as to the areas they frequent seasonally (which may be separate for migrants), requires distinguishing migration from other movement behaviours, which might be a challenge. Methods We aimed at assessing seasonal movement behaviours, including migratory, resident, dispersing, and nomadic, for caribou belonging to the Barren-ground and Woodland subspecies and ecotypes. We examined seasonal displacement, both planar and altitudinal, and seasonal ranges overlap for 366 individuals that were GPS-collared in Northern and Western Canada. Lastly, we assessed the ability of caribou individuals to switch between migratory and non-migratory movement behaviours between years. Results We detected migratory behaviour within each of the studied subspecies and ecotypes. However, seasonal ranges overlap (an index of sedentary behaviour) varied, with proportions of clear migrants (0 overlap) of 40.94% for Barren-ground caribou and 23.34% for Woodland caribou, and of 32.95%, 54.87%, and 8.86% for its Northern Mountain, Central Mountain, and Boreal ecotype, respectively. Plastic switches of individuals were also detected between migratory, resident, dispersing, and nomadic seasonal movements performed across years. Conclusions Our unexpected findings of marked seasonal movement plasticity in caribou indicate that this phenomenon should be better studied to understand the resilience of this endangered species to habitat and climatic changes. Our results that a substantial proportion of individuals engaged in seasonal migration in all studied ecotypes indicate that caribou conservation plans should account for critical habitat in both summer and winter ranges. Accordingly, conservation strategies are being devised for the Woodland subspecies and its ecotypes, which were found to be at least partially migratory in this study. Our findings that migration is detectable with both planar and altitudinal analyses of seasonal displacement provide a tool to better define seasonal ranges, also in mountainous and hilly environments, and protect habitat there.

Erwinia amylovora is a Gram-negative bacterium, responsible for the fire blight disease in Rosaceae plants. Its virulence is correlated with the production of an exopolysaccharide (EPS) called amylovoran, which protects the bacterium from the surrounding environment and helps its diffusion inside the host. Amylovoran biosynthesis relies on the expression of twelve genes clustered in the ams operon. One of these genes, amsI, encodes for a Low Molecular Weight Protein Tyrosine Phosphatase (LMW-PTP) called EaAmsI, which plays a key role in the regulation of the EPS production pathway. For this reason, EaAmsI was chosen in this work as a target for the development of new antibacterial agents against E. amylovora. To achieve this aim, a set of programs (DOCK6, OpenEye FRED) was selected to perform a virtual screening using a database of ca. 700 molecules. The six best-scoring compounds identified were tested in in vitro assays. A complete inhibition kinetic characterization carried out on the most promising molecule (n-Heptyl β-D-glucopyranoside, N7G) showed an inhibition constant of 7.8 ± 0.6 µM. This study represents an initial step towards the development of new EaAmsI inhibitors able to act as antibacterial agents against E. amylovora infections.

The seamless integration of human disease-related mutation data into protein structures is an essential component of any attempt to correctly assess the impact of the mutation. The key step preliminary to any structural modelling is the identification of the isoforms onto which mutations should be mapped due to there being several functionally different protein isoforms from the same gene. To handle large sets of data coming from omics techniques, this challenging task needs to be automatized. Here we present the MoNvIso (Modelling eNvironment for Isoforms) code, which identifies the most useful isoform for computational modelling, balancing the coverage of mutations of interest and the availability of templates to build a structural model of both the wild-type isoform and the related variants.

Inhibition of respiratory complex I (CI) is becoming a promising anti-cancer strategy, encouraging the design and the use of inhibitors, whose mechanism of action, efficacy and specificity remain elusive. As CI is a central player of cellular bioenergetics, a finely tuned dosing of targeting drugs is required to avoid side effects. We compared the specificity and mode of action of CI inhibitors metformin, BAY 87-2243 and EVP 4593 using cancer cell models devoid of CI. Here we show that both BAY 87-2243 and EVP 4593 were selective, while the antiproliferative effects of metformin were considerably independent from CI inhibition. Molecular docking predictions indicated that the high efficiency of BAY 87-2243 and EVP 4593 may derive from the tight network of bonds in the quinone binding pocket, although in different sites. Most of the amino acids involved in such interactions are conserved across species and only rarely found mutated in human. Our data make a case for caution when referring to metformin as a CI-targeting compound, and highlight the need for dosage optimization and careful evaluation of molecular interactions between inhibitors and the holoenzyme.

Background: Monitoring biodiversity is crucial in biogeography. Citizen science and biodiversity platforms have revolutionized data access across taxa, but they struggle to provide robust raw data essential for conservation decisions. Aims: This study addresses data gaps for under‐represented species and locations, observer expertise variability, and the lack of absence data and sampling effort information to improve data representation and suitability for statistical analyses. Materials & Methods: We collected, compared to IUCN‐recognized taxonomic groups, all worldwide living being (animal, plant and fungi) observations held by four major biodiversity platforms: eBird, GBIF, iNaturalist, and Observation.org. We also organized such observations by country of origin and based on their Human Development Index (HDI). Results: We found that, while GBIF, iNaturalist, and Observation.org cover all life forms, birds are the most observed (eBird is a bird‐specific platform), whereas fish, other marine organisms, arthropods, and invertebrates are dramatically underrepresented. Moreover, none of the above‐mentioned biodiversity platforms considered or directly analysed expertise variability among observers and, apart from eBird, the other three biodiversity platforms do not accommodate data on species absence and sampling effort. Discussion and Conclusion: Finally, we found that species observations on biodiversity platforms considered in this study are skewed towards high HDI countries, primarily North America and Europe. By enhancing the effectiveness of biodiversity platforms, this study has the potential to significantly advance the field of biogeography, paving the way for more informed and effective conservation strategies. Overall, our findings underscore the untapped potential of these platforms in contributing to our understanding of the spatial and temporal patterns of biodiversity. [ABSTRACT FROM AUTHOR]

Abstract Disease lesion mimic (DLM) or necrotic mutants display necrotic lesions in the absence of pathogen infections. They can show improved resistance to some pathogens and their molecular dissection can contribute to revealing components of plant defense pathways. Although forward‐genetics strategies to find genes causal to mutant phenotypes are available in crops, these strategies require the production of experimental cross populations, mutagenesis, or gene editing and are time‐ and resource‐consuming or may have to deal with regulated plant materials. In this study, we described a collection of 34 DLM mutants in barley (Hordeum vulgare L.) and applied a novel method called complementation by sequencing (CBS), which enables the identification of the gene responsible for a mutant phenotype given the availability of two or more chemically mutagenized individuals showing the same phenotype. Complementation by sequencing relies on the feasibility to obtain all induced mutations present in chemical mutants and on the low probability that different individuals share the same mutated genes. By CBS, we identified a cytochrome P450 CYP71P1 gene as responsible for orange blotch DLM mutants, including the historical barley nec3 locus. By comparative phylogenetic analysis we showed that CYP71P1 gene family emerged early in angiosperm evolution but has been recurrently lost in some lineages including Arabidopsis thaliana (L.) Heynh. Complementation by sequencing is a straightforward cost‐effective approach to clone genes controlling phenotypes in a chemically mutagenized collection. The TILLMore (TM) collection will be instrumental for understanding the molecular basis of DLM phenotypes and to contribute knowledge about mechanisms of host–pathogen interaction.

RK Wayne has arguably been the most influential geneticist of canids, famously promoting the conservation of wolves in his homeland, the United States. His influence has been felt in other countries and regions outside the contiguous United States, where he inspired others, also including former graduate students and research fellows of his, to use modern molecular techniques to examine the evolutionary biology of canids to inform the conservation and management of wolves. In this review, we focus on the implications of Wayne's work on wolves outside the United States. He envisioned a clear future for wolf conservation research, involving the study of wolves' ecological and genetic diversity, and the description of ecotypes requiring conservation. He also documented widespread hybridization among canids and introgression of DNA from domestic dogs to wolves, a process that started dozens of thousands of years ago. His work therefore calls for innovative studies, such as examining the potential fitness benefits of introgression. Inspired by his results, for example, on the purging of deleterious alleles in small populations, wolf researchers should use novel molecular tools to challenge other conservation genetics paradigms. Overall, RK Wayne's work constitutes a call for answers, which as scientists or citizens concerned with conservation matters, we are obliged to address, as we contribute to monitoring and maintaining biodiversity during our period of dramatic transformations of the biosphere. [ABSTRACT FROM AUTHOR]