67 research outputs found
Dissipation in planar resonant planetary systems
Close-in planetary systems detected by the Kepler mission present an excess
of periods ratio that are just slightly larger than some low order resonant
values. This feature occurs naturally when resonant couples undergo dissipation
that damps the eccentricities. However, the resonant angles appear to librate
at the end of the migration process, which is often believed to be an evidence
that the systems remain in resonance.
Here we provide an analytical model for the dissipation in resonant planetary
systems valid for low eccentricities. We confirm that dissipation accounts for
an excess of pairs that lie just aside from the nominal periods ratios, as
observed by the Kepler mission. In addition, by a global analysis of the phase
space of the problem, we demonstrate that these final pairs are non-resonant.
Indeed, the separatrices that exist in the resonant systems disappear with the
dissipation, and remains only a circulation of the orbits around a single
elliptical fixed point. Furthermore, the apparent libration of the resonant
angles can be explained using the classical secular averaging method. We show
that this artifact is only due to the severe damping of the amplitudes of the
eigenmodes in the secular motion.Comment: 18 pages, 20 figures, accepted to A&
Algorithms for zero-dimensional ideals using linear recurrent sequences
Inspired by Faug\`ere and Mou's sparse FGLM algorithm, we show how using
linear recurrent multi-dimensional sequences can allow one to perform
operations such as the primary decomposition of an ideal, by computing the
annihilator of one or several such sequences.Comment: LNCS, Computer Algebra in Scientific Computing CASC 201
The antimalarial MMV688533 provides potential for single-dose cures with a high barrier to
The emergence and spread of Plasmodium falciparum resistance to first-line antimalarials creates an imperative to identify and develop potent preclinical candidates with distinct modes of action. Here, we report the identification of MMV688533, an acylguanidine that was developed following a whole-cell screen with compounds known to hit high-value targets in human cells. MMV688533 displays fast parasite clearance in vitro and is not cross-resistant with known antimalarials. In a P. falciparum NSG mouse model, MMV688533 displays a long-lasting pharmacokinetic profile and excellent safety. Selection studies reveal a low propensity for resistance, with modest loss of potency mediated by point mutations in PfACG1 and PfEHD. These proteins are implicated in intracellular trafficking, lipid utilization, and endocytosis, suggesting interference with these pathways as a potential mode of action. This preclinical candidate may offer the potential for a single low-dose cure for malaria
The antimalarial MMV688533 provides potential for single-dose cures with a high barrier to
The emergence and spread of Plasmodium falciparum resistance to first-line antimalarials creates an imperative to identify and develop potent preclinical candidates with distinct modes of action. Here, we report the identification of MMV688533, an acylguanidine that was developed following a whole-cell screen with compounds known to hit high-value targets in human cells. MMV688533 displays fast parasite clearance in vitro and is not cross-resistant with known antimalarials. In a P. falciparum NSG mouse model, MMV688533 displays a long-lasting pharmacokinetic profile and excellent safety. Selection studies reveal a low propensity for resistance, with modest loss of potency mediated by point mutations in PfACG1 and PfEHD. These proteins are implicated in intracellular trafficking, lipid utilization, and endocytosis, suggesting interference with these pathways as a potential mode of action. This preclinical candidate may offer the potential for a single low-dose cure for malaria
A baby steps/giant steps Monte Carlo algorithm for computing roadmaps in smooth compact real hypersurfaces
International audienceWe consider the problem of constructing roadmaps of real algebraic sets. The problem was introduced by Canny to answer connectivity questions and solve motion planning problems. Given polynomial equations with rational coefficients, of degree in variables, Canny's algorithm has a Monte Carlo cost of operations in ; a deterministic version runs in time . The next improvement was due to Basu, Pollack and Roy, with an algorithm of deterministic cost for the more general problem of computing roadmaps of semi-algebraic sets ( is the dimension of an associated object). We give a Monte Carlo algorithm of complexity for the problem of computing a roadmap of a compact hypersurface of degree in variables; we also have to assume that has a finite number of singular points. Even under these extra assumptions, no previous algorithm featured a cost better than
EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA); Scientific Opinion on Dietary Reference Values for fats, including saturated fatty acids, polyunsaturated fatty acids, monounsaturated fatty acids, trans fatty acids, and cholesterol
This Opinion of the EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA) deals with the setting of Dietary Reference Values (DRVs) for fats. A lower bound of the reference intake range for total fat of 20 energy % (E%) and an upper bound of 35 E% are proposed. Fat intake in infants can gradually be reduced from 40 E% in the 6-12 month period to 35-40 E% in the 2nd and 3rd year of life. For specific fatty acids the following is proposed: saturated fatty acid (SFA) and trans fatty acid intake should be as low as possible; not to set any DRV for cis-monounsaturated fatty acids; not to formulate a DRV for the intake of total cis-polyunsaturated fatty acids (PUFA); not to set specific values for the n-3/n-6 ratio; to set an Adequate Intake (AI) of 4 E% for linolenic acid; not to set any DRV for arachidonic acid; not to set an UL for total or any of the n-6 PUFA; to set an AI for alpha-linilenic acid (ALA) of 0.5 E%; not to set an UL for ALA; to set an AI of 250 mg for eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) for adults; to set an AI of 100 mg DHA for infants (>6 months) and young children <24 months; to increase by 100-200 mg preformed DHA in addition to the AI for adults as an adequate supply of n-3 long chain PUFA during pregnancy and lactation; not to set any DRV for conjugated linoleic acid. For cholesterol it was decided not to propose a reference value beside the limitation on the intake of SF
Using Gröbner bases to compute higher order finite elements for ma\ss lumping
Numerical Methods in Differential Equations,Contributed Lectures C-31International audienceno abstrac
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