Publications by authors named "Baptiste Picard"

Weaned southern elephant seals (SES) quickly transition from terrestrial to aquatic life after a 5- to 6-week post-weaning period. At sea, juveniles and adult elephant seals present extreme, continuous diving behaviour. Previous studies have highlighted the importance of the post-weaning period for weanlings to prepare for the physiological challenges of their future sea life.

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Understanding the ontogeny of diving behaviour in marine megafauna is crucial owing to its influence on foraging success, energy budgets, and mortality. We compared the ontogeny of diving behaviour in two closely related species-northern elephant seals ( = 4) and southern elephant seals ( = 9)-to shed light on the ecological processes underlying migration. Although both species have similar sizes and behaviours as adults, we discovered that juvenile northern elephant seals have superior diving development, reaching 260 m diving depth in just 30 days, while southern elephant seals require 160 days.

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Lactation is the most energy-demanding event in mammals' reproduction. In pinnipeds, females are the only food providers to the young and have developed numerous behavioral and physiological lactation strategies, from capital-breeding to income-breeding. Lactating females' fine-scale foraging strategy, and precise understanding of how females supplement their pup's needs as well as their own are important to understand the species' ecology and energetic balance.

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Among pinnipeds, southern elephant seals (SESs, Mirounga leonina) are extreme divers that dive deeply and continuously along foraging trips to restore their body stores after fasting on land during breeding or moulting. Their replenishment of body stores influences their energy expenditure during dives and their oxygen (O2) reserves (via muscular mass), yet how they manage their O2 stores during their dives is not fully understood. In this study, 63 female SESs from Kerguelen Island were equipped with accelerometers and time-depth recorders to investigate changes in diving parameters through their foraging trips.

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Background: Studying animal movement in the context of the optimal foraging theory has led to the development of simple movement metrics for inferring feeding activity. Yet, the predictive capacity of these metrics in natural environments has been given little attention, raising serious questions of the validity of these metrics. The aim of this study is to test whether simple continuous movement metrics predict feeding intensity in a marine predator, the southern elephant seal (SES; Mirounga leonine), and investigate potential factors influencing the predictive capacity of these metrics.

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An improved carbonylation method allowing amide bond formation between aryl iodides and aromatic amines is presented. In contrast to usual methods based on Pd catalysis, this method does not require a phosphine ligand. The catalyst system simply employs bis(dibenzylideneacetone)palladium (0.

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Radical carbonylation offers potent methods for introducing carbon monoxide into organic molecules. This feature article focuses on our current efforts to develop new strategies for radical carbonylation, which include electron-transfer carbonylation, site-selective C(sp)-H carbonylation by a photocatalyst and ring-opening carbonylation.

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Aminocarbonylation of alkenyl iodides with CO and amines proceeded under heating to produce α,β-unsaturated amides in good yields (23 examples, 71% average yield). This catalyst-free method exhibited good functional-group tolerance, and open a straightforward access to functionalized acrylamides, as illustrated by the synthesis of Ilepcimide. A hybrid radical/ionic mechanism involving chain electron transfer is proposed for this transformation.

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-Cbz-α-tosylglycinate ester was combined with aldehydes in a redox-neutral sequence leading to 2-oxazolone-4-carboxylates with high functional group tolerance. While the scope of the method was delineated to primary and secondary aliphatic aldehydes as well as aromatics, no racemization occurred with chiral aldehydes such as Garner's. Hitherto unknown, this process relies on the ambivalent role of -Cbz-α-tosylglycinate ester acting as a pronucleophile.

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Incubating eggs represents a trade-off for parent birds between spending enough time fasting to take care of the clutch and to get enough nutrients for self-maintenance. It is believed that the pituitary hormone prolactin plays an important role in such allocation processes. Incubation does not solely imply the active warming of the eggs but also the active egg-turning to facilitate absorption of albumen by the embryo, reduce malposition and prevent the embryo from adhering to the inner shell membrane.

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Despite international prohibition, some ill-intentioned states and organisations have shown their will and capacity to run chemical weapon programs, and the number of incidents involving chemical warfare agents (CWA) has significantly increased in recent years. Herein, we aimed to offer a clear overview of chemical warfare agents to organic chemists not specialized in this field by (1) introducing the main CWAs and their relevant simulants legally usable in academic laboratories and (2) presenting a selection of recent and soft neutralisation methods, such as organocatalysis and continuous flow, and materials such as metal-organic frameworks and polyoxometalates. These modern approaches offer potential future alternatives to "heavy" decontamination methods.

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In birds, incubation-related behaviors and brood patch formation are influenced by hormonal regulation such as prolactin secretion. Brood patch provides efficient heat transfer between the incubating parent and the developing embryo in the egg. Importantly, several environmental contaminants are already known to have adverse effects on avian reproduction.

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Antarctic coastal polynyas are regions of persistent open water and are thought to be key bio-physical features within the sea-ice zone. However, their use by the upper trophic levels of ecosystems remains unclear. A unique bio-physical dataset recorded by southern elephant seals reveals that East Antarctic polynyas are a key winter foraging habitat for male seals.

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Marine endotherms living in cold water face an energetically challenging situation. Unless properly insulated, these animals will lose heat rapidly. The field metabolic rate of king penguins at sea is about twice that on land.

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The fast and effective neutralization of the mustard-gas simulant 2-chloroethyl ethyl sulfide (CEES) using a simple and portable continuous flow device is reported. Neutralization takes place through a fully selective sulfoxidation by a stable source of hydrogen peroxide (alcoholic solution of urea-H O adduct/MeSO H freshly prepared). The reaction progress can be monitored with an in-line benchtop NMR spectrometer, allowing a real-time adjustment of reaction conditions.

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Bioluminescence is produced by a broad range of organisms for defense, predation or communication purposes. Southern elephant seal (SES) vision is adapted to low-intensity light with a peak sensitivity, matching the wavelength emitted by myctophid species, one of the main preys of female SES. A total of 11 satellite-tracked female SESs were equipped with a time-depth-light 3D accelerometer (TDR10-X) to assess whether bioluminescence could be used by SESs to locate their prey.

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Understanding the diving behaviour of diving predators in relation to concomitant prey distribution could have major practical applications in conservation biology by allowing the assessment of how changes in fine scale prey distribution impact foraging efficiency and ultimately population dynamics. The southern elephant seal (Mirounga leonina, hereafter SES), the largest phocid, is a major predator of the southern ocean feeding on myctophids and cephalopods. Because of its large size it can carry bio-loggers with minimal disturbance.

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Assessing energy gain and expenditure in free ranging marine predators is difficult. However, such measurements are critical if we are to understand how variation in foraging efficiency, and in turn individual body condition, is impacted by environmentally driven changes in prey abundance and/or accessibility. To investigate the influence of oceanographic habitat type on foraging efficiency, ten post-breeding female southern elephant seals Mirounga leonina (SES) were equipped and tracked with bio-loggers to give continuous information of prey catch attempts, body density and body activity.

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Poorly nucleophilic aromatic amines (nitroanilines, chloroanilines, etc.) react readily and selectively with trans-4-methoxy-3-buten-2-one, a convenient, effective and inexpensive surrogate for 3-butyn-2-one, to afford (Z)-enaminones. The efficiency of the reaction mostly lies in the use of water as a solvent, which enhances the reaction rate by a 45 to 200-fold factor with regard to other media.

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The combined use of Tf2NH and L(Au)(+)X(-) as a dual or binary catalytic system clearly improves the efficiency and enlarges the scope of the tandem intermolecular Friedel-Crafts α-amidoalkylation/intramolecular hydroarylation sequence, compared to an "all gold" multicatalysis approach.

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Mature female southern elephant seals (Mirounga leonina) come ashore only in October to breed and in January to moult, spending the rest of the year foraging at sea. Mature females may lose as much as 50% of their body mass, mostly in lipid stores, during the breeding season due to fasting and lactation. When departing to sea, post-breeding females are negatively buoyant, and the relative change in body condition (i.

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