We developed new methods for parameter estimation-in-context and, with the help of 125 authors, built the AmP (Add-my-Pet) database of Dynamic Energy Budget (DEB) models, parameters and referenced underlying data for animals, where each species constitutes one database entry. The combination of DEB parameters covers all aspects of energetics throughout the full organism’s life cycle, from the start of embryo development to death by aging. The species-specific parameter values capture biodiversity and can now, for the first time, be compared between animals species. An important insight brought by the AmP project is the classification of animal energetics according to a family of related DEB models that is structured on the basis of the mode of metabolic acceleration, which links up with the development of larval stages. We discuss the evolution of metabolism in this context, among animals in general, and ray-finned fish, mollusks and crustaceans in particular. New DEBtool code for estimating DEB parameters from data has been written. AmPtool code for analyzing patterns in parameter values has also been created. A new web-interface supports multiple ways to visualize data, parameters, and implied properties from the entire collection as well as on an entry by entry basis. The DEB models proved to fit data well, the median relative error is only 0.07, for the 1035 animal species at 2018/03/12, including some extinct ones, from all large phyla and all chordate orders, spanning a range of body masses of 16 orders of magnitude. This study is a first step to include evolutionary aspects into parameter estimation, allowing to infer properties of species for which very little is known.

We study the very recently discovered Θ + (1540) at SPring-8, at ITEP and at CLAS-Thomas Jefferson Lab. We apply the same RGM techniques that already explained with success the repulsive hard core of nucleon-nucleon, kaon-nucleon exotic scattering, and the attractive hard core present in pion-nucleon and pion-pion non-exotic scattering. We find that the K − N repulsion excludes the Θ + as a K − N s-wave pentaquark. We explore the Θ + as a heptaquark, equivalent to a N + π + K borromean bound-state, with positive parity and total isospin I = 0. We find that the kaon-nucleon repulsion is cancelled by the attraction existing both in the pion-nucleon and pion-kaon channels. Although we are not yet able to bind the total three body system, we find that the Θ + may still be a heptaquark state. We conclude with predictions that can be tested experimentally.

A dynamic energy budget (DEB) model for microalgae is proposed. This model deviates from the standard DEB model as it needs more reserves to cope with the variation of assimilation pathways, requiring a different approach to growth based on the synthesizing unit (SU) theory for multiple substrates. It is shown that the model is able to accurately predict experimental data in constant and light-varying conditions with most of the parameter values taken directly from the literature. Also, model simulations are shown to be consistent with stylized facts (SFs) concerning N : C ratio. These SFs are reinterpreted and the general conclusion is that all forcing variables (dilution rate, temperature and irradiance) impose changes in the nitrogen or carbon limitation status of the population, and consequently on reserve densities. Model predictions are also evaluated in comparison with SFs on chlorophyll concentration. It is proposed that an extra structure, more dependent on the nitrogen reserve, is required to accurately model chlorophyll dynamics. Finally, SFs concerning extracellular polymeric substances (EPSs) production by benthic diatoms are collected and interpreted and a formulation based on product synthesis and rejection flux is proposed for the EPSs production rate.

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Alterations of the amount and quality of food consumed during ontogeny can affect different life-history traits, such as growth rate, developmental time, survival, adult size, and fitness. Understanding the dynamics of such metabolic and energetic pathways and investments is particularly challenging in the case of holometabolous insects due to their strikingly different life stages. We show how whole life-cycle energy and mass budgets can be achieved for holometabolic insects through dynamic energy budget (DEB) theory, permitting the fate of acquired and stored nutrients to be followed over a complete life-cycle. We applied the DEB theory to model the whole life-cycle energetics of an endoparasitic wasp, Venturia canescens (Hymenoptera: Ichneumonidae). Data on embryo, larval, and pupal dry mass, imago longevity, and fecundity were used for assessing the goodness of fit of the model. Our model predicted the growth curves of the larval and pupal stages, the number of eggs laid by the imago through time, and lifespan events, such as the different developmental times of the parasitoid. The model enabled us to distinguish and follow the energy invested in eggs through income and capital reserves. The mechanisms leading to the double costs of being small (a shorter life under starving conditions and fewer eggs) were identified by running the model for varying amounts of food eaten early in life, according to host sizes. The final larval instar harvests around 60 times the energy of a recently hatched larva. Around 90% of this energy is then used during pupation to build the structure of the imago and to pay maintenance. Imagoes, therefore, emerge with only a small percentage of the energy stored by the last instar larvae. Our study shows that, despite being small, this percentage of energy stored during the parasitoid development has a great impact on adult fitness, the loss of which cannot be compensated for by a rich adult environment. Our model is generic and has applications for a wide range of applied and theoretical questions about insect energetics, from population dynamics in multitrophic systems to responses to climate change and life-history strategies. (Résumé d'auteur

We address the old difficulty in accommodating the scalar quark-antiquark confining potential together with chiral symmetry breaking. We develop a quark confining potential inspired in the QCD scalar flux tube. The coupling to quarks consists in a double vector vertex. We study the Dirac and spin structure of this potential. In the limit of massless quarks, the quark vertex is vector. Nevertheless, symmetry breaking generates a new scalar quark vertex. In the heavy quark limit, the coupling is mostly scalar. We solve the mass gap equation and find that this potential produces spontaneous chiral symmetry breaking for light quarks. The quantitative results of this model are encouraging.

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Identifying the drivers that control the reproductive success of a population is vital to forecasting the consequences of climate change in terms of distribution shift and population dynamics. In the present study, we aimed to improve our understanding of the environmental conditions that allowed the colonization of the Pacific oyster, Crassostrea gigas, in the Bay of Brest since its introduction in the 1960s. We also aimed to evaluate the potential consequences of future climate change on its reproductive success and further expansion. Highlights ► The DEB model available for the Pacific oyster was applied in a new coastal environment: the bay of Brest (France). ► This version was successfully calibrated using a new dataset covering 6 years (from 2009 to 2014) of field monitoring. ► The model successfully predicted in detail the complex reproductive processes of C. gigas, especially its spawning behavior. ► Hindcasting and forecasting simulations of the reproductive phenology of C. gigas were performed using IPCC scenarios.