Mass Parameterizations and Predictions of Isotopic Observables

We discuss the accuracy of mass models for extrapolating to very asymmetric nuclei and the impact of such extrapolations on the predictions of isotopic observables in multifragmentation. We obtain improved mass predictions by incorporating measured masses and extrapolating to unmeasured masses with a mass formula that includes surface symmetry and Coulomb terms. We find that using accurate masses has a significant impact on the predicted isotopic observables.Comment: 12 pages, 4 figure

Thermally-induced expansion in the 8 GeV/c π−\pi^- + 197^{197}Au reaction

Fragment kinetic energy spectra for reactions induced by 8.0 GeV/c $\rm{\pi^-}$ beams incident on a $\rm{^{197}}$Au target have been analyzed in order to deduce the possible existence and influence of thermal expansion. The average fragment kinetic energies are observed to increase systematically with fragment charge but are nearly independent of excitation energy. Comparison of the data with statistical multifragmentation models indicates the onset of extra collective thermal expansion near an excitation energy of E*/A $\rm{\approx}$ 5 MeV. However, this effect is weak relative to the radial expansion observed in heavy-ion-induced reactions, consistent with the interpretation that the latter expansion may be driven primarily by dynamical effects such as compression/decompression.Comment: 12 pages including 4 postscript figure

Effect of the intermediate velocity emissions on the quasi-projectile properties for the Ar+Ni system at 95 A.MeV

The quasi-projectile (QP) properties are investigated in the Ar+Ni collisions at 95 A.MeV taking into account the intermediate velocity emission. Indeed, in this reaction, between 52 and 95 A.MeV bombarding energies, the number of particles emitted in the intermediate velocity region is related to the overlap volume between projectile and target. Mean transverse energies of these particles are found particularly high. In this context, the mass of the QP decreases linearly with the impact parameter from peripheral to central collisions whereas its excitation energy increases up to 8 A.MeV. These results are compared to previous analyses assuming a pure binary scenario

Surveying the nuclear caloric curve

International audienceThe 4π array INDRA was used to detect nearly all charged products emitted in Ar + Ni collisions between 52 and 95 MeV/u. The charge, mass and excitation energy E∗ of the quasi-projectiles have been reconstructed event by event. Excitation energies up to 25 MeV per nucleon are reached

Use of recorded nursing grunts during lactation in two breeds of sows. II. Effects on sow performance and mammary development

International audienc

The importance of dietary selenium on antioxidant status and hormonal profile in post-pubertal gilts

International audienc

Effect of dietary organic and inorganic selenium on antioxidant status, embryo development, and reproductive performance in hyperovulatory first-parity gilts

International audienceThis project aimed to determine the effect of Se as inorganic Na-selenite (MSe) or organic Se-yeast (OSe) on antioxidant status, hormonal profile, reproductive performance, and embryo development in first-parity gilts. Forty-nine gilts were allocated to 1 of the 3 dietary treatments starting at first pubertal estrus and lasting up to 30 d after AI: control [CONT: basal diet (Se = 0.2 mg/kg) without added Se; n = 16], MSe (CONT + 0.3 mg/kg of MSe; n = 16), and OSe (CONT + 0.3 mg/kg of OSe; n = 17). Blood was collected from all gilts on the day after each onset of estrus and on d 30 after AI. Blood was also collected daily from d −4 to d +4 of the third onset of estrus (d 0) in 8 CONT, 9 MSe, and 8 OSe cannulated gilts. Gilts had received, after d 14 and 15 of their third estrus, a hormonal challenge to induce super-ovulation. At slaughter, embryos and corpora lutea (CL) were weighed and measured. Blood Se was less (P < 0.01) in CONT than in Se gilts and greater in OSe than in MSe (P < 0.01) from the first estrus until d 30 of gestation. At the same time, blood Se-dependent glutathione peroxidase (GSH-Px) decreased for CONT gilts, whereas it increased for both Se groups. The increase was greater in MSe than in OSe gilts (treatment × time, P = 0.02). Plasma 3,3′,5-triiodothyronine and thyroxine concentrations for MSe tended to be less than for OSe gilts (P < 0.06). In cannulated gilts, plasma FSH tended to change among treatments (treatment × time, P = 0.06), and plasma estradiol-17β (E2) was less (P = 0.01) for MSe than for OSe. There was no treatment effect on mean litter size or embryonic antioxidant status. The Se content of individual embryos was greater for Se-treated than for CONT gilts (P = 0.03), and Se content of individual embryos and total litter was greater for OSe than for MSe gilts (P < 0.01). The length, weight, and protein content of embryos were greater in OSe than in MSe gilts (P < 0.05). There was no treatment effect on weight, length, Se content, and ferric reducing antioxidant power of CL, but GSH-Px in CL was greater for Se than for CONT gilts (P = 0.02). In summary, the Se status response of gilts to dietary Se was affected by both the quantity and the source of Se dietary supplements. Moreover, the uterine transfer of Se to embryos was improved with OSe as compared with MSe, and this was concomitant with an enhanced development of embryos

Bioinformatique du transcriptome de Buchnera, symbiote intracellulaire des pucerons

International audienceBuchnera est une bactérie symbiotique intracellulaire associée à la plupart des pucerons d'importance économique. Cette bactérie incultivable est obligatoire pour le puceron qui se nourrit exclusivement de sève phloémienne. Buchnera est caractérisée par la taille extrêmement réduite de son génome (400 à 600 kb) séquencé entièrement chez trois espèces. Une des particularités fonctionnelles tout à fait originale de cette bactérie est la conservation des voies de biosynthèse des acides aminés essentiels, alors que les gènes des voies de synthèse des acides aminés non essentiels (ceux que l'hôte est capable de synthétiser) sont perdus. Jusqu'à présent l'analyse expérimentale des réponses métaboliques et moléculaires ne pouvait s'effectuer que "voie par voie". Le développement de la technique des puces à ADN permet maintenant d'envisager une approche globale. Dans l'UMR BF2I, nous avons développé une puce à ADN dédiée à l'analyse du transcriptome de Buchnera APS (associée au puceron Acyrthosiphon pisum). Cette puce devrait nous permettre d’étudier les mécanismes de régulation de l’expression des gènes de cette bactérie symbiotique en condition de stress trophique de son hôte (pucerons élevés sur des milieux déprimés en acides aminés essentiels par exemple).Ce travail correspond à l'émergence d'une thématique de recherche en bioinformatique à l'INSA associée au développement de la plate-forme transcriptome de la Génopole Rhône-Alpes sur le campus de la Doua. Notre approche s'est voulue verticale, impliquant la création d'outils bioinformatiques lorsqu'ils faisaient défaut. Quatre points seront présentés ici : Le développement d'un Système d'Information pour l'Analyse du Transcriptome (SI-Trans) Le développement d'un logiciel de choix d'oligonucléotides (ROSO) La validation d’un protocole expérimental grâce au développement d’une « minipuce » Buchnera L’intégration des résultats d'expression dans une base de connaissance (Genome Expert Bacteria) pour la représentation des réseaux de régulatio