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The differences in rorqual feeding ecology have been linked to the presence of different morphological markers. The Antarctic minke whale (Balaenoptera bonaerensis Burmeister, 1867) and the common minke whale (Balaenoptera acutorostrata Lacepede, 1804) are closely related species, but their morphological differences have not been fully investigated. In this study, we compared 21 skull and 11 feeding apparatus (baleen and mouth-related parts) measurement points between these two species using hundreds of individuals covering a wide range of body lengths in both sexes. Their engulfment capacities were estimated using these measurements. Our results show that Antarctic minke whales have (i) proportionally larger skulls to the body length, (ii) more dorsoventrally and laterally curved rostra, (iii) proportionally larger feeding apparatuses to the condylobasal length, and (iv) significantly larger engulfment capacity than common minke whales. These differences could indicate that Antarctic minke whales have developed a feeding strategy suitable for feeding on krill, which forms large schools. In contrast, common minke whales have adapted to prey on small pelagic fishes that are agile and form small schools. Key words: Balaenoptera bonaerensis, Balaenoptera acutorostrata, Antarctic minke whale, common minke whale, skull morphology, feeding morphology, engulfment capacity. Les differences sur le plan de l'ecologie de l'alimentation chez les rorquals ont ete associees a la presence de differents marqueurs morphologiques. Bien que le rorqual antarctique (Balaenoptera bonaerensis Burmeister, 1867) et le petit rorqual (Balaenoptera acutorostrata Lacepede, 1804) soient des especes etroitement reliees, leurs differences morphologiques n'ont pas ete examinees de maniere exhaustive. Nous avons compare 21 et 11 mesures du crane et de l'appareil d'alimentation (fanons et parties buccales), respectivement, obtenues de centaines de specimens des deux especes couvrant une grande fourchette de longueurs du corps pour les deux sexes. La capacite d'engouffrement a ete estimee a la lumiere de ces mesures. Nos resultats montrent que les rorquals antarctiques ont (i) des cranes proportionnellement plus grands par rapport a la longueur du corps, (ii) des rostres a plus forte courbure dorsoventrale et laterale, (iii) des appareils d'alimentation proportionnellement plus grands par rapport a la longueur condylobasale et (iv) une capacite d'engouffrement significativement plus grande que les petits rorquals. Ces differences pourraient indiquer que les rorquals antarctiques ont developpe une strategie d'alimentation adaptee a la consommation de krill, qui forme de grands bancs, alors que les petits rorquals se sont adaptes a la consommation de petits poissons pelagiques agiles formant de petits bancs. [Traduit par la Redaction] Mots-cles : Balaenoptera bonaerensis, Balaenoptera acutorostrata, rorqual antarctique, petit rorqual, morphologie cranienne, morphologie de l'appareil alimentaire, capacite d'engouffrement., Introduction Feeding is one of the most fundamental aspects for any animal species, as it is directly tied to their survival. Each cetacean species has its own feeding ecology (i.e., [...]

This study examines a class of time-dependent constitutive equations used to describe viscoelastic materials under creep in solid mechanics. In nonlinear elasticity, the strain response to the applied stress is expressed via an implicit graph allowing multi-valued functions. For coercive and maximal monotone graphs, the existence of a solution to the quasi-static viscoelastic problem is proven by applying the Browder–Minty fixed point theorem. Moreover, for quasi-linear viscoelastic problems, the solution is constructed as a semi-analytic formula. The inverse viscoelastic problem is represented by identification of a design variable from non-smooth measurements. A non-empty set of optimal variables is obtained based on the compactness argument by applying Tikhonov regularization in the space of bounded measures and deformations. Furthermore, an illustrative example is given for the inverse problem of isotropic kernel identification. This article is part of the theme issue 'Non-smooth variational problems with applications in mechanics'. [ABSTRACT FROM AUTHOR]

Light propagation through diffusive media can be described by the diffusion equation in a space–time domain. Furthermore, fluorescence can be described by a system of coupled diffusion equations. This paper analyzes time-domain measurements. In particular, the temporal point-spread function is measured at the boundary of a diffusive medium. Moreover, the temporal profile of fluorescence is considered. In both cases, we refer to the maximum temporal position of measured light as the peak time. In this paper, we provide proofs of the existence and uniqueness of the peak time and give explicit expressions of the peak time. The relationship between the peak time and the object position in a medium is clarified. [ABSTRACT FROM AUTHOR]

This paper proves some regularity criteria for the Hall-MHD system in terms of the pressure and the magnetic field. [ABSTRACT FROM AUTHOR]

This work evaluates the defects in HfZrO as a function of Zr addition into HfO2 and when the dielectric was subjected to a slot-plane-antenna (SPA) plasma treatment in a cyclic process to form TiN/HfZrO/SiON/Si gate stacks. The defect energy levels, estimated by temperature-dependent current-voltage measurements, suggest that Zr addition in HfO2 modifies the charge state of the oxygen vacancy formation, V+. The influence of electron affinity variation of Hf and Zr ions on the charged oxygen vacancy levels seems to have contributed to the increase in defect activation energy, Ea, from 0.32 eV to 0.4 eV. The cyclic SPA plasma exposure further reduces the oxygen vacancy formation because of the film densification. When the dielectric was subjected to a constant voltage stress, the charge state oxygen vacancy formation changes to V2+ and improvement was eliminated. The trap assisted tunneling behavior, as observed by the stress induced leakage current characteristics, further supports the oxygen vacancy formation model. [ABSTRACT FROM AUTHOR]

This paper proves the existence, uniqueness and stability of solutions of an inverse problem for the 2-D Navier–Stokes equations with the final overdetermination with L2 initial data and sufficiently large viscosity. [ABSTRACT FROM AUTHOR]

We deal with the problem of recovery of an unknown inclusion located in a medium Ω by prescribing a heat flux on the boundary of Ω and measuring the corresponding temperature. In particular, we provide an upper and a lower bound on the size of the inclusion. We also show the validity and the accuracy of the method with some numerical examples. [ABSTRACT FROM AUTHOR]

The BaF2-YF3 system was partially investigated, with focus given to the BaY2F8 compound and its neighboring phases. In this report, various difficulties that hinder the thermal analysis investigation of this binary fluoride system are described in detail. Samples of various compositions ranging from 58 to 79% YF3 were prepared and subjected to thermal analysis (DTA, TG and DSC) and X-ray diffraction. Diffraction patterns were analyzed through the Rietveld method for the calculation of phase concentrations in samples and determination of the lattice parameters of monoclinic BaY2F8. Thermal results were compared with data from the literature and discrepancies were found. [ABSTRACT FROM AUTHOR]

This paper deals with a two or three dimensional inverse scattering problem for identifying a sound hard obstacle in a homogeneous medium. We provide a reconstruction scheme for identifying the obstacle from far field patterns of scattered waves associated with incident waves in all directions when the obstacle is not necessarily convex. [ABSTRACT FROM AUTHOR]