Microscopic analysis of multipole susceptibility of actinide dioxides: A scenario of multipole ordering in AmO2_2

By evaluating multipole susceptibility of a seven-orbital impurity Anderson model with the use of a numerical renormalization group method, we discuss possible multipole states of actinide dioxides at low temperatures. In particular, here we point out a possible scenario for multipole ordering in americium dioxide. For Am$^{4+}$ ion with five $5f$ electrons, it is considered that the ground state is $\Gamma_7^{-}$ doublet and the first excited state is $\Gamma_8^{-}$ quartet, but we remark that the $f^5$ ground state is easily converted due to the competition between spin-orbit coupling and Coulomb interactions. Then, we find that the $\Gamma_8^-$ quartet can be the ground state of AmO$_2$ even for the same crystalline electric field potential. In the case of $\Gamma_8^-$ quartet ground state, the numerical results suggest that high-order multipoles such as quadrupole and octupole can be relevant to AmO$_2$.Comment: 8 pages, 4 figures. To appear in Phys. Rev.

PLoS ONE

Lyme disease is a multisystemic disorder caused by B. burgdorferi sl. The molecular basis for specific organ involvement is poorly understood. The skin plays a central role in the development of Lyme disease as the entry site of B. burgdorferi in which specific clones are selected before dissemination. We compared the skin inflammatory response (antimicrobial peptides, cytokines and chemokines) elicited by spirochete populations recovered from patients presenting different clinical manifestations. Remarkably, these spirochete populations induced different inflammatory profiles in the skin of C3H/HeN mice. As spirochete population transmitted into the host skin is heterogeneous, we isolated one bacterial clone from a population recovered from a patient with neuroborreliosis and compared its virulence to the parental population. This clone elicited a strong cutaneous inflammatory response characterized by MCP-1, IL-6 and antimicrobial peptides induction. Mass spectrometry of this clone revealed 110 overexpressed proteins when compared with the parental population. We further focused on the expression of nine bacterial surface proteins. bb0347 coding for a protein that interacts with host fibronectin, allowing bacterial adhesion to vascular endothelium and extracellular matrix, was found to be induced in host skin with another gene bb0213 coding for a hypothetical protein. These findings demonstrate the heterogeneity of the B. burgdorferi ss population and the complexity of the interaction involved early in the skin

Sex-Specific Growth and Reproductive Dynamics of Red Drum in the Northern Gulf of Mexico

The Red Drum Sciaenops ocellatus stock is heavily targeted in the Gulf of Mexico (GOM) by recreational fishers and supports a small commercial fishery in Mississippi. Despite their popularity, little recent work has been done to describe their life history. In this work, we describe sex‐specific growth and reproductive dynamics of Red Drum collected from the northern GOM from September 2016 through October 2017. We evaluated seven candidate growth models and found that the three‐parameter von Bertalanffy growth function (VBGF) was the best candidate length‐at‐age model. No significant difference in growth between sexes was observed with the three‐parameter VBGF, despite the female‐specific curve having a larger mean asymptotic length than the male‐specific curve. All seven candidate growth models predicted similar mean length‐at‐age estimates, and four of them exhibited significant differences in sex‐specific mean length at age, with females reaching a larger length at age than males after age 5. There was no significant difference between the sex‐specific weight‐at‐length relationships. Red Drum are batch spawners that spawn in northern GOM coastal waters during August and September. We estimated 3.7 d between spawns and 10.5 spawning events per female in 2017. Nearly 20% of fish collected during the spawning season were sexually mature but reproductively inactive, indicating the possibility of skipped spawning. The age at 50% maturity was around 3 years (length at 50% maturity = 670 mm TL) in both sexes, but fish were not spawning capable until age 4.5 (703 mm TL) in males and age 5.8 (840 mm TL) in females. Furthermore, elevated gonadosomatic indices were not observed until around age 5–6. The updated life history information presented in this work helps to address current data limitations and provides critical information for future assessments of Red Drum stocks in the northern GOM

LIF-Dependent Signaling: New Pieces in the Lego

LIF, a member of the IL6 family of cytokine, displays pleiotropic effects on various cell types and organs. Its critical role in stem cell models (e.g.: murine ES, human mesenchymal cells) and its essential non redundant function during the implantation process of embryos, in eutherian mammals, put this cytokine at the core of many studies aiming to understand its mechanisms of action, which could benefit to medical applications. In addition, its conservation upon evolution raised the challenging question concerning the function of LIF in species in which there is no implantation. We present the recent knowledge about the established and potential functions of LIF in different stem cell models, (embryonic, hematopoietic, mesenchymal, muscle, neural stem cells and iPSC). We will also discuss EVO-DEVO aspects of this multifaceted cytokine

Physics and Modeling of Plasma Display Panels

We discuss physical phenomena which take place in an AC Plasma Display Panel (PDP) cell for matrix and coplanar electrode geometries. The effect of the gas mixture and the electrode geometry on the breakdown voltage is first analyzed using a fluid discharge model. We then compare solutions from simple fluid models and more accurate hybrid models for a 1D cell, and discuss the sensitivity of the models to the uncertainties on the charged particle transport coefficients. Finally we present typical results showing the space and time evolution of a discharge in AC matrix and coplanar cells

Excess drain noise simulations in ultra thin oxides MOSFETs

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Neutron diffraction study on U0.5Np0.5O2 at low temperatures

The results of a neutron diffraction study on U0.5Np0.5 O2 solid solution at low temperature are reported. Below T = 12 K the solid solution is magnetically ordered with a magnetic structure different from that of the UO2 low temperature phase. The temperature dependence of the observed magnetic line width could suggest an eventual short range nature of the magnetic order. The neutron diffraction results are supported by Mössbauer spectroscopy measurements.La solution solide U0,5Np0,5O2 s'ordonne en dessous de 12 K et présente une structure magnétique différente de celle observée pour UO2. L'évolution de la largeur de la raie magnétique en fonction de la température pourrait suggérer un ordre magnétique à courte distance

Neutron diffraction study of 243AmO2

The actinide compound AmO2 was studied by neutron diffraction at different temperatures in order to check the occurrence of antiferromagnetism below 8.5 K as predicted by magnetic susceptibility measurements. No antiferromagnetic order was observed in agreement with Mössbauer results. Furthermore, the coherent neutron scattering length of Am and the Debye-Waller factors for Am and O were determined.L'oxyde d'américium AmO2 a été étudié par diffraction neutronique à différentes températures afin de vérifier l'apparition d'une phase antiferromagnétique en dessous de 8,5 K que des mesures de susceptibilité magnétique avaient prévue. Aucun ordre antiferromagnétique n'a été observé en accord avec des expériences Mössbauer. De plus, la longueur de Fermi de l'americium et les facteurs de température de l'americium et de l'oxygène ont été déterminés