Search results for "Aub"
showing 10 items of 136 documents
Slow Dynamics of the Magnetization in One-Dimensional Coordination Polymers: Single-Chain Magnets
2009
18 pages; International audience; Slow relaxation of the magnetization (i.e., "magnet-like" behavior) in materials composed of magnetically isolated chains was observed for the first time in 2001. This type of behavior was predicted in the 1960s by Glauber in a chain of ferromagnetically coupled Ising spins (the so-called Glauber dynamics). In 2002, this new class of nanomagnets was named single-chain magnets (SCMs) by analogy to single-molecule magnets that are isolated molecules displaying related superparamagnetic properties. A long-range order occurs only at T = 0 K in any pure one-dimensional (1D) system, and thus such systems remain in their paramagnetic state at any finite temperatur…
Behavioral and Chemical Investigations of Contact Kairomones Released by the Mud Dauber Wasp Trypoxylon politum, a Host of the Parasitoid Melittobia …
2011
Contact kairomones from the host mud dauber wasp Trypoxylon politum Say (Hymenoptera: Crabronidae) that mediate behavioral responses of its ectoparasitoid Melittobia digitata Dahms (Hymenoptera: Eulophidae) were investigated. Chemical residues from host by-products, the cocoon, and the meconium, induced arrestment behavior of macropterous female parasitoids, while those from the host stage attacked, i.e., the prepupa, did not. Melittobia digitata response to polar and apolar extracts of host by-products indicated kairomone(s) solubility mainly in hexane. GC and GC/MS analysis of cocoon and meconium apolar extracts revealed a mixture of linear carboxylic acids from C(6) to C(18), and both ex…
Carnauba wax microspheres loaded with valproic acid: Preparation and evaluation of drug release
1995
AbstractTo minimize unwanted toxic effects of valproic acid (1) by the kinetic control of drug release, gastroresistant carnauba wax microspheres loaded with the antiepileptic agent were prepared. The preparation was based on a technique involving melting and dispersion of drug-containing wax in an aqueous medium. The resulting emulsion after cooling under rapid stirring produced solid, discrete, reproducible free flowing microspheres which converted the liquid drug droplets into solid material. About 94% of the isolated microspheres were of particle size range 200-425 μm. The microspheres were analyzed to determine the drug content in various particle size range and to characterize the in …
The Phylogenetic position of Daubentonia madagascariensis (Gmelin, 1788; primates, Strepsirhini) as revealed by chromosomal analysis
2012
One of the major topics in primate evolution is the phylogenetic position of the bizarre Daubentonia madagascariensis (DMA, aye-aye). The principal points that have been discussed for many decades are whether the aye-aye is: (i) the sister group of primates; (ii) the sister group of strepsirhines; or (iii) the sister group of lemurs. Very little is known about Daubentonia evolution, particularly on the chromosomal background. The present report focuses on the chromosomal history of this species. We used available chromosome painting data as the main source to identify conserved chromosomes, chromosomal segments and syntenic associations that have characterized the aye-aye karyotype. The dat…
Heavy-tail properties of relaxation time distributions underlying the Havriliak–Negami and the Kohlrausch–Williams–Watts relaxation patterns
2007
Abstract A detailed discussion of asymptotic properties of the Havriliak–Negami and the Kohlrausch–Williams–Watts relaxation time distributions is presented. The heavy-tail property of the Havriliak–Negami relaxation time distribution, leading to the infinite mean relaxation time, is discussed. In contrast, the existence of the finite mean relaxation time for the Kohlrausch–Williams–Watts response is shown. The discussion of the Cole–Davidson and the Cole–Cole cases is also included. Using the Tauberian theorems we show that these properties are determined directly by the asymptotic behavior of the considered empirical functions.
Pseudorapidity Density of Charged Particles inp+PbCollisions atsNN=5.02 TeV
2013
The charged-particle pseudorapidity density measured over four units of pseudorapidity in nonsingle-diffractive p + Pb collisions at a center-of-mass energy per nucleon pair root s(NN) = 5.02 TeV is presented. The average value at midrapidity is measured to be 16.81 +/- 0.71 (syst), which corresponds to 2.14 +/- 0.17 (syst) per participating nucleon, calculated with the Glauber model. This is 16% lower than in nonsingle-diffractive pp collisions interpolated to the same collision energy and 84% higher than in d + Au collisions at root s(NN) = 0.2 TeV. The measured pseudorapidity density in p + Pb collisions is compared to model predictions and provides new constraints on the description of …
Shadowing in Inelastic Nucleon-Nucleon Cross Section?
2020
Experimental results of inclusive hard-process cross sections in heavy-ion collisions conventionally lean on a normalization computed from Glauber models where the inelastic nucleon-nucleon cross section $\sigma_{\rm nn}^{\rm inel}$ -- a crucial input parameter -- is simply taken from proton-proton measurements. In this letter, using the computed electro-weak boson production cross sections in lead-lead collisions as a benchmark, we determine $\sigma_{\rm nn}^{\rm inel}$ from the recent ATLAS data. We find a significantly suppressed $\sigma_{\rm nn}^{\rm inel}$ relative to what is usually assumed, show the consequences for the centrality dependence of the cross sections, and address the phe…
The eikonal model of reactions involving exotic nuclei; Roy Glauber's legacy in today's nuclear physics
2020
In this contribution, the eikonal approximation developed by Roy Glauber to describe high-energy quantum collisions is presented. This approximation has been-and still is-extensively used to analyse reaction measurements performed to study the structure of nuclei far from stability. This presentation focuses more particularly on the application of the eikonal approximation to the study of halo nuclei in modern nuclear physics. To emphasise Roy Glauber's legacy in today's nuclear physics, recent extensions of this model are reviewed.
Constraints from $v_2$ fluctuations for the initial state geometry of heavy-ion collisions
2014
The ability to accurately compute the series of coefficients $v_n$ characterizing the momentum space anisotropies of particle production in ultrarelativistic heavy ion collisions as a function of centrality is widely regarded as a triumph of fluid dynamics as description of the bulk matter evolution. A key ingredient to fluid dynamical modeling is however the initial spatial distribution of matter as created by a yet not completely understood equilibration process. A measurement directly sensitive to this initial state geometry is therefore of high value for constraining models of pre-equilibrium dynamics. Recently, it has been shown that such a measurement is indeed possible in terms of th…
HΛ3 and H‾Λ¯3 production in Pb–Pb collisions at sNN=2.76 TeV
2019
Abstract The production of the hypertriton nuclei H Λ 3 and H ‾ Λ ¯ 3 has been measured for the first time in Pb–Pb collisions at s NN = 2.76 TeV with the ALICE experiment at LHC. The p T -integrated H Λ 3 yield in one unity of rapidity, d N / d y × B . R . ( H Λ 3 → He 3 , π − ) = ( 3.86 ± 0.77 ( stat. ) ± 0.68 ( syst. ) ) × 10 − 5 in the 0–10% most central collisions, is consistent with the predictions from a statistical thermal model using the same temperature as for the light hadrons. The coalescence parameter B 3 shows a dependence on the transverse momentum, similar to the B 2 of deuterons and the B 3 of 3He nuclei. The ratio of yields S 3 = H Λ 3 / ( He 3 × Λ / p ) was measured to b…