Publications by authors named "Bernier N"

While corticosteroids, including cortisol, have conserved osmoregulatory functions, the relative involvement of other stress-related hormones in osmoregulatory processes remains unclear. To address this gap, we initially characterized the gill corticotropin-releasing factor (CRF) system of Atlantic salmon (Salmo salar) and then determined: 1) how it is influenced by osmotic disturbances; 2) whether it is affected by cortisol; and 3) which physiological processes it regulates in the gills. Most CRF system components were expressed in the gills with CRF receptor 2 (crfr2a), CRF binding protein (crfbp1 and crfbp2), and urocortin 2 (ucn2a) being the most abundant.

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This article presents low-loss mid-infrared waveguides fabricated on a Ge-rich SiGe strain-relaxed buffer grown on an industrial-scale 200 mm wafer, with propagation losses below 0.5 dB/cm for 5-7 µm wavelengths and below 5 dB/cm up to 11 µm. Investigation reveals free-carrier absorption as the primary loss factor for 5-6.

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The neuropeptides arginine vasopressin (AVP) and oxytocin (OXT) are key regulators of social behaviour across vertebrates. However, much of our understanding of how these neuropeptide systems interact with social behaviour is centred around laboratory studies which fail to capture the social and physiological challenges of living in the wild. To evaluate relationships between these neuropeptide systems and social behaviour in the wild, we studied social groups of the cichlid fish Neolamprologus pulcher in Lake Tanganyika, Africa.

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Amphibious fishes on land encounter higher oxygen (O) availability and novel energetic demands, which impacts metabolism. Previous work on the amphibious mangrove killifish (Kryptolebias marmoratus) has shown that cortisol becomes elevated in response to air exposure, suggesting a possible role in regulating metabolism as fish move into terrestrial environments. We tested the hypothesis that cortisol is the mechanism by which oxidative processes are upregulated during the transition to land in amphibious fishes.

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The first study related to the characteristics of the riverine litter was carried out at the mouth of the Cimandiri River in the southern West Java to provide a national database, as mandated in the Indonesian Presidential Regulation 83/2018 concerning the handling of marine debris. We examined floating riverine litter entering the South Java Sea at Cimandiri River outlets four times between December 2020 and October 2021 using a Thomsea 1 T trawl-net. The amount of litter collected tended to rise throughout the sampling period.

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Predicted climate change-induced increases in heat waves and hypoxic events will have profound effects on fishes, yet the capacity of parents to alter offspring phenotype via non-genetic inheritance and buffer against these combined stressors is not clear. This study tested how prolonged adult zebrafish exposure to combined diel cycles of thermal stress and hypoxia affect offspring early survival and development, parental investment of cortisol and heat shock proteins (HSPs), larval offspring stress responses, and both parental and offspring heat and hypoxia tolerance. Parental exposure to the combined stressor did not affect fecundity, but increased mortality, produced smaller embryos and delayed hatching.

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We used yellow perch (Perca flavescens) captured at four sites differing in legacy industrial pollution in the Lake St. Clair-Detroit River system to evaluate the lingering sublethal effects of industrial pollution. We emphasized bioindicators of direct (toxicity) and indirect (chronic stress, impoverished food web) effects on somatic and organ-specific growth (brain, gut, liver, heart ventricle, gonad).

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Harmful algal blooms (HABs) release toxic compounds in water and are increasing in frequency worldwide. The neurotoxin β-methylamino-l-alanine (BMAA) is released by HABs and has garnered much attention over the past 20 years due to its association with human neurodegenerative disorders, but its effects on wildlife are still largely unknown. This study characterized the effects of chronic exposure to environmentally relevant concentrations of BMAA on the behavior and brain size of developing zebrafish (Danio rerio).

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The maternal match hypothesis predicts that maternal exposure to a stressor may help prepare offspring to cope with the same disturbance in later life. Although there is support for this hypothesis, the signals involved in non-genetic inheritance are unclear. In this study, we tested how adult zebrafish exposure to diel cycles of thermal stress (27-36°C), hypoxia (20-85% dissolved oxygen) or the combined treatment affects maternal and embryonic levels of cortisol and heat shock proteins (HSPs).

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As many busy parents will attest, caring for young often comes at the expense of having time to feed and care for oneself. Galanin is a neuropeptide that regulates food intake and modulates parental care; however, the relative importance of galanin in the regulation of feeding versus caring by parents has never been evaluated before under naturalistic settings. Here, we assessed how expression of the galanin system varied in two brain regions, the hypothalamus (which regulates feeding) and the preoptic area (which modulates social behaviours including care) in a wild cichlid fish, Neolamprologus pulcher.

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Juvenile rainbow trout (Oncorhynchus mykiss) develop social hierarchies when competing for resources in a constrained environment. Among the physiological consequences of social status are changes in organismal energy metabolism, which generally favour anabolic pathways in dominant fish and catabolic pathways in subordinate fish. The somatotropic axis is an important regulator of metabolism and growth that could be involved in mediating metabolic changes in response to social status in juvenile rainbow trout.

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To achieve optimal sports performances, women and men may show specific doping practices because of the physiological and psychological gender differences, but there are few data on this topic. Here, we report the apparent use of prohibited substances and methods by female athletes based on analyses of the doping tests collected by the French Anti-Doping Agency from 2013 to 2019. We compared the frequency of use and the ergogenic and side effects to those of their male counterparts.

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Large inter-individual variability of activation strategies is observed during hamstring strengthening exercises but their consequences remain unexplored. The objective of this study was to determine whether individual activation strategies are related to the distribution of damage across the hamstring muscle heads semimembranosus (SM), semitendinosus (ST), and biceps femoris (BF) after eccentric contractions. 24 participants performed 5 sets of 15 maximal eccentric contractions of knee flexors on a dynamometer, while activation of each muscle head was assessed using surface electromyography.

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Diadromous fishes undergo dramatic changes in osmoregulatory capacity in preparation for migration between freshwater and seawater. One of the primary hormones involved in coordinating these changes is the glucocorticoid hormone, cortisol. In Atlantic salmon (), cortisol levels increase during the spring smoltification period prior to seawater migration; however, the neuroendocrine factors responsible for regulating the hypothalamic-pituitary-interrenal (HPI) axis and plasma cortisol levels during smoltification remain unclear.

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Cortisol is a major osmoregulatory hormone in fishes. Cortisol acts upon the gills, the primary site of ionoregulation, through modifications to specialized ion-transporting cells called ionocytes. We tested the hypothesis that cortisol also acts as a major regulator of skin ionocyte remodelling in the amphibious mangrove rivulus () when gill function ceases during the water-to-land transition.

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Fish nursery habitats are increasingly hypoxic and the brain is recognized as highly hypoxia sensitive, yet there is a lack of information on the effects of hypoxia on the development and function of the larval fish brain. Here, we tested the hypothesis that by inhibiting brain development, larval exposure to severe hypoxia has persistent functional effects on the cortisol stress response in zebrafish (Danio rerio). Exposing 5 days post-fertilization (dpf) larvae to 10% dissolved O2 (DO) for 16 h only marginally reduced survival, but it decreased forebrain neural proliferation by 55%, and reduced the expression of neurod1, gfap and mbpa, markers of determined neurons, glia and oligodendrocytes, respectively.

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Host-guest interactions represent a growing research area with recent work demonstrating the ability to chemically manipulate both host molecules as well as guest molecules to vary the type and strength of bonding. Much less is known about the interactions of the guest molecules and hybrid materials containing similar chemical features to typical macrocyclic hosts. This work uses in vitro and in vivo kinetic analyses to investigate the interaction of -dodecahydrododecaborate derivatives with ferumoxytol, an iron oxide nanoparticle with a carboxylated dextran coating.

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Individuals that live in groups experience different challenges based on their social rank and sex. Glucocorticoids have a well-established role in coordinating responses to challenges and glucocorticoid levels often vary between ranks and sexes. However, the neuroendocrine mechanisms regulating glucocorticoid dynamics in wild groups are poorly understood, making it difficult to determine the functional consequences of differences in glucocorticoid levels.

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Fishes respond to different abiotic and biotic stressors through changes in gene expression as a part of an integrated physiological response. Transcriptomics approaches have been used to quantify gene expression patterns as a reductionist approach to understand responses to environmental stressors in animal physiology and have become more commonly used to study wild fishes. We argue that non-lethal sampling for transcriptomics should become the norm for assessing the physiological status of wild fishes, especially when there are conservation implications.

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Networks are widely used as mathematical models of complex systems across many scientific disciplines. Decades of work have produced a vast corpus of research characterizing the topological, combinatorial, statistical, and spectral properties of graphs. Each graph property can be thought of as a feature that captures important (and sometimes overlapping) characteristics of a network.

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The ^{80}Ge structure was investigated in a high-statistics β-decay experiment of ^{80}Ga using the GRIFFIN spectrometer at TRIUMF-ISAC through γ, β-e, e-γ, and γ-γ spectroscopy. No evidence was found for the recently reported 0_{2}^{+} 639-keV level suggested as evidence for low-energy shape coexistence in ^{80}Ge. Large-scale shell model calculations performed in ^{78,80,82}Ge place the 0_{2}^{+} level in ^{80}Ge at 2 MeV.

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Individuals often respond to social disturbances by increasing prosociality, which can strengthen social bonds, buffer against stress, and promote overall group cohesion. Given their importance in mediating stress responses, glucocorticoids have received considerable attention as potential proximate regulators of prosocial behaviour during disturbances. However, previous investigations have largely focused on mammals and our understanding of the potential prosocial effects of glucocorticoids across vertebrates more broadly is still lacking.

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Unlabelled: At the end of October 2018, a storm of unprecedented strength severely damaged the forests of the eastern sector of the Italian Alps. The affected forest area covers 42,500 ha. The president of one of the damaged regions asked for help from the University of Padua.

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Laser interaction with solids is routinely used for functionalizing materials' surfaces. In most cases, the generation of patterns/structures is the key feature to endow materials with specific properties like hardening, superhydrophobicity, plasmonic color-enhancement, or dedicated functions like anti-counterfeiting tags. A way to generate random patterns, by means of generation of wrinkles on surfaces resulting from laser melting of amorphous Ge-based chalcogenide thin films, is presented.

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