Contaminant-Associated Disruption of the Skin Transcriptome in the Endangered St. Lawrence Estuary Beluga.

The St. Lawrence Estuary (SLE) beluga () population in Canada is Endangered, and endocrine disrupting contaminants, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and other halogenated flame retardants, have been identified as a threat to the recovery of this population. Here, potential impacts of these contaminants on SLE beluga were evaluated by comparing skin transcriptome profiles and biological pathways between this population and a population less exposed to contaminants (Eastern Beaufort Sea) used as a reference.

Developmental exposure to legacy environmental contaminants, medial temporal lobe volumes and spatial navigation memory in late adolescents.

Exposure to lead, mercury, and polychlorinated biphenyls (PCBs) has been causally linked to spatial memory deficits and hippocampal changes in animal models. The Inuit community in Northern Canada is exposed to higher concentrations of these contaminants compared to the general population. This study aimed to 1) investigate associations between prenatal and current contaminant exposures and medial temporal brain volumes in Inuit late adolescents; 2) examine the relationship between these brain structures and spatial memory; and 3) assess the mediating role of brain structures in the association between contaminant exposure and spatial memory.

Nanoparticles as Delivery Systems for Antigenic Saccharides: From Conjugation Chemistry to Vaccine Design.

Glycoconjugate vaccines have been effective in preventing numerous bacterial infectious diseases and have shown recent potential to treat cancers through active immunotherapy. Soluble polysaccharides elicit short-lasting immune responses and are usually covalently linked to immunogenic carrier proteins to enhance the antigen-specific immune response by stimulating T-cell-dependent mechanisms. Nonetheless, the conjugation of purified polysaccharides to carrier proteins complexifies vaccine production, and immunization with protein glycoconjugates can lead to the undesirable immunogenic interference of the carrier.

Fiscal externalities and underinvestment in early-life human capital: Optimal policy instruments for a developing country.

We study policy instruments to correct inefficiently low investment in maternal nutrition in India, where one-fifth of all births occur. We focus on fiscal externalities: healthier babies become more productive adults, who pay more tax. However, parents do not internalize this externality, which, combined with other distortions, results in mothers weighing too little during pregnancy.

Converting the Amyloidogenic Islet Amyloid Polypeptide into a Potent Nonaggregating Peptide Ligand by Side Chain-to-Side Chain Macrocyclization.

The islet amyloid polypeptide (IAPP), also known as amylin, is a hormone playing key physiological roles. However, its aggregation and deposition in the pancreatic islets are associated with type 2 diabetes. While this peptide adopts mainly a random coil structure in solution, its secondary conformational conversion into α-helix represents a critical step for receptor activation and contributes to amyloid formation and associated cytotoxicity.

Probing the molecular determinants of the activation of toll-like receptor 2/6 by amyloid nanostructures through directed peptide self-assembly.

Amyloid fibrils are proteinaceous nanostructures known for their ability to activate the innate immune system, which has been recently exploited for their use as self-adjuvanted antigen delivery systems for vaccines. Among mechanisms of immunostimulation, the activation of the heterodimeric toll-like receptor 2/6 (TLR2/TLR6) by the cross-β-sheet quaternary conformation appears important. Nonetheless, the lack of control over the process of self-assembly and the polydispersity of the resulting supramolecular architectures make it challenging to elucidate the molecular basis of TLR2/TLR6 engagement by amyloid assemblies.

How do outside-hosts-overwintering parasitoids, at the adult stage, cope with cold?

Introduction: When overwintering, most endoparasitoids are protected from the cold inside their hosts. However, some endoparasitoids, along with ectoparasitoids, fall into the category called outside-hosts-overwintering parasitoids (OHOP) at immature or adult stages. We compared the cold-hardiness capacity and strategy between adult OHOP and their hosts (HOST) by examining their supercooling points (SCP), with acclimation periods and acclimation temperatures, and their lower lethal temperatures at 50% mortality (LLT50).

Influence of Particle Size on Mass Transport during the Oxygen Reduction Reaction at Single Silver Particles Using Scanning Electrochemical Cell Microscopy.

Single entity electrochemical measurements enable insight into the electrocatalytic activity of individual particles based on composition, shape, and crystallographic orientation. In addition to structural effects, particle size can further influence electrocatalytic activity and reaction mechanisms through mass transport effects. In this work, electrodeposition was used to grow well-separated silver particles of varying sizes from 100 to 500 nm in radius.

What Determines the Adoption of Conservation Agriculture? Evidence from Quebec.

Conservation agriculture (CA) is promoted by various organisations and scholars as alternative to conventional agriculture to meet growing food demand with minimal damage on environment; but its factors of adoption have not been well identified. The study uses the recent composite index of adoption of CA developed by Takam Fongang et al. (2023) to analyse the factors of adoption of conservation agriculture among maize and soybean farmers in Quebec.

Convergent Synthesis of a Group B Type III Epitope Toward a Semisynthetic Carbohydrate-Based Vaccine.

In this work, we synthesized an hexasaccharide derived from the capsular polysaccharide of group B type III capsular polysaccharide. Our convergent 3 + 3 strategy avoided the use of benzyl protecting groups allowing the installation of an azide anchoring group and providing a high yield for the final deprotection steps. Moreover, the minimal hexasaccharidic epitope was conjugated to CRM and BSA via copper-catalyzed azide-alkyne cycloaddition for the preparation of a semisynthetic carbohydrate-based vaccine.

Emerging investigator series: nontargeted screening of aryl hydrocarbon receptor agonists in endangered beluga whales from the St. Lawrence Estuary: beyond legacy contaminants.

The elevated concentrations of organohalogen contaminants in the endangered St. Lawrence Estuary (SLE) belugas have prompted the hypothesis that aryl hydrocarbon receptor (AhR) activity may be a contributor towards their potential adverse effects. While indirect associations between AhR and contaminant levels have been reported in SLE beluga tissues, AhR activity was never directly measured.

Poly(N-Heterocyclic Carbene)-Capped Alloy and Core-Shell AuAg Bimetallic Nanoparticles.

N-Heterocyclic carbene (NHC)-stabilized metal nanoparticles (NPs) have recently attracted considerable attention. While most efforts in the field have been devoted to the development of NHC-tethered monometallic NPs and enhancing their stabilities under various conditions, their bimetallic counterparts are rare in the literature. Herein, we demonstrate that the covalent immobilization of Au and Ag atoms on polymerized NHCs is a powerful method to access bimetallic AuAg NPs.

Influence of Guidance on Occupational Image and Traineeship's Satisfaction of Vocational Students.

Initial vocational training (VT) in high school consists of short-term programs leading to employment in a skilled trade. To better align training with employment opportunities and to encourage students to stay in the programs until they graduate, most programs include traineeship. Since traineeships involve acquiring skills directly on the job, they require greater involvement of supervisors to guide the trainees.

Methylmercury in northern pike (Esox lucius) liver and hepatic mitochondria is linked to lipid peroxidation.

Methylmercury (MeHg) readily bioaccumulates and biomagnifies in aquatic food webs leading to elevated concentrations in fish and may thus induce toxicity. Oxidative stress is a suggested effect of MeHg bioaccumulation in fish. However, studies on how MeHg triggers oxidative stress in wild fish are scarce.

Differential neural correlates underlying visuospatial versus semantic reasoning in autistic children.

While fronto-posterior underconnectivity has often been reported in autism, it was shown that different contexts may modulate between-group differences in functional connectivity. Here, we assessed how different task paradigms modulate functional connectivity differences in a young autistic sample relative to typically developing children. Twenty-three autistic and 23 typically developing children aged 6 to 15 years underwent functional magnetic resonance imaging (fMRI) scanning while completing a reasoning task with visuospatial versus semantic content.

Variations in thyroid hormone levels in endangered St. Lawrence Estuary belugas: Potential linkage with stress and organohalogen contaminant exposure.

The St. Lawrence Estuary (SLE) beluga (Delphinapterus leucas) population is highly exposed to an array of contaminants that were identified as one of the causes to the non-recovery of this endangered and declining population. In the last decade, an increasing number of parturition-associated complications and calf mortality has been reported in this population.

Check your outliers! An introduction to identifying statistical outliers in R with easystats.

Beyond the challenge of keeping up to date with current best practices regarding the diagnosis and treatment of outliers, an additional difficulty arises concerning the mathematical implementation of the recommended methods. Here, we provide an overview of current recommendations and best practices and demonstrate how they can easily and conveniently be implemented in the R statistical computing software, using the {performance} package of the easystats ecosystem. We cover univariate, multivariate, and model-based statistical outlier detection methods, their recommended threshold, standard output, and plotting methods.

New Canadian amber deposit fills gap in fossil record near end-Cretaceous mass extinction.

Amber preserves an exceptional record of tiny, soft-bodied organisms and chemical environmental signatures, elucidating the evolution of arthropod lineages and the diversity, ecology, and biogeochemistry of ancient ecosystems. However, globally, fossiliferous amber deposits are rare in the latest Cretaceous and surrounding the Cretaceous-Paleogene (K-Pg) mass extinction. This faunal gap limits our understanding of arthropod diversity and survival across the extinction boundary.

What are the views of Quebec and Ontario citizens on the tiebreaker criteria for prioritizing access to adult critical care in the extreme context of a COVID-19 pandemic?

Background: The prioritization protocols for accessing adult critical care in the extreme pandemic context contain tiebreaker criteria to facilitate decision-making in the allocation of resources between patients with a similar survival prognosis. Besides being controversial, little is known about the public acceptability of these tiebreakers. In order to better understand the public opinion, Quebec and Ontario's protocols were presented to the public in a democratic deliberation during the summer of 2022.

Implementing a mental health app library in primary care: A feasibility study.

Confronted with a wide range of digital health tools (DHT), professionals and patients need guidance to use these tools correctly and optimize health management. In the fall of 2020, a DHT library developed by Quebec-based company TherAppX was implemented in 22 institutions. The library was designed to enable healthcare professionals to use DHT in clinical care.

Intranasal delivery of a self-adjuvanted nanovaccine composed of the curli filaments and the highly conserved M2e epitope confers protection against influenza a virus in mice.

Intranasal administration of vaccines is an attractive delivery route to fight viral respiratory infections. However, there are only a few intranasal vaccines used in human, emphasizing the critical need to identify novel safe mucosal adjuvants and antigen delivery systems to expand their usage. We recently revealed an immunostimulating nanoparticle based on a fragment (R4R5) of the Curli-specific gene A (CsgA) protein that confers protection against influenza A virus (IAV) when conjugated to three repeats of the highly conserved M2e epitope and administrated intramuscularly.

A Window into the Use of Post-diagnostic Services for Autism and Parents' Perspective on the Quality of Early Childhood Services Trajectory in a Canadian Province.

The pathway for post-diagnostic services for autism tends to be complex, heterogeneous, and fraught with delays. This situation has repercussions for families' experience with care systems, the quality of early interventions, and family adjustment. To date, studies of parents' point of view on autism services have predominantly focused on the diagnostic phase of the services trajectory.