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Piano Stool Aminoalkylidene-Ferracyclopentenone Complexes from Bimetallic Precursors: Synthesis and Cytotoxicity Data
No full textThe reaction of pyrrolidine with a series of cationic diiron cyclopentadienyl complexes containing a bridging vinyliminium ligand gives access to piano stool monoiron complexes based on a five-membered metallacycle that includes a vinyl-aminoalkylidene moiety, in moderate to high yields. The resulting metallacyclic motif (aminoalkylidene-ferracyclopentenone) is unique in organometallic chemistry and is partially pre-constructed on the dinuclear frame. The monoiron products were fully characterized by elemental analysis, IR and multinuclear NMR spectroscopy, and in a number of cases by X-ray diffraction and cyclic voltammetry. They are robust in aqueous solutions and generally unreactive towards alkylating agents in organic solvents. However, a cationic derivative was prepared in high yield by methylation of a 2-pyridyl group. The cytotoxicity of both neutral and ionic complexes was assessed on cancerous (A2780 and A280cisR) and non-cancerous (HEK293) cell lines, revealing the influence of local structural modifications on the antiproliferative activity and the selectivity of the compounds.LCO
Spectroscopy evidences for true Landau Fermi quasiparticles in LSCO
No full textImproving our knowledge of the normal state of high-temperature cuprate superconductors is believed to represent an important, and maybe necessary, step to advance in our understanding of their unconventional superconducting state. In this talk we present an angle resolved photoemission spectroscopy of an overdoped cuprate system (La1.77Sr0.23CuO4) [1,2]. We will show how the nodal low-energy excitations are consistent with true Landau Fermi quasiparticles [1]. Furthermore, we will show how the quasiparticle description of the excitations breaks down both for high energies and in spectra recorded in the anti-nodal region [2]. [1] C. G. Fatuzzo et al., submitted. [2] J. Chang et al., Nature Communications, 4, 2559 (2013)LQ
A Natural Actor-Critic Framework for Zero-Sum Markov Games
No full textWe introduce algorithms based on natural actorcritic and analyze their sample complexity for solving two player zero-sum Markov games in the tabular case. Our results improve the best-known sample complexities of policy gradient/actorcritic methods for convergence to Nash equilibrium in the multi-agent setting. We use the error propagation scheme in approximate dynamic programming, recent advances for global convergence of policy gradient methods, temporal difference learning, and techniques from stochastic primal-dual optimization. Our algorithms feature two stages, requiring agents to agree on an etiquette before starting their interactions, which is feasible for instance in self-play. However, the agents only access to joint reward and joint next state and not to each other’s actions or policies. Our complexity results match the best-known results for global convergence of policy gradient algorithms for single agent RL. We provide numerical verification of our methods for a two player bandit environment and a two player game, Alesia. We observe improved empirical performance as compared to the recently proposed optimistic gradient descent-ascent variant for Markov games.LION
Search for Monotop Signatures in Proton-Proton Collisions at 8 TeV
No full textResults are presented from a search for new decaying massive particles whose presence is inferred from an imbalance in transverse momentum and which are produced in association with a single top quark that decays into a bottom quark and two light quarks. The measurement is performed using 19.7 fb-1 of data from proton-proton collisions at a center-of-mass energy of 8 TeV, collected with the CMS detector at the CERN LHC. No deviations from the standard model predictions are observed and lower limits are set on the masses of new invisible bosons. In particular, scalar and vector particles, with masses below 330 and 650 GeV, respectively, are excluded at 95% confidence level, thereby substantially extending a previous limit published by the CDF Collaboration.LPH
Nano-Bio-Technology and Sensing Chips: New Systems for Detection in Personalized Therapies and Cell Biology
No full textFurther advances in molecular medicine and cell biology also require new electrochemical systems to detect disease biomarkers and therapeutic compounds. Microelectronic technology offers powerful circuits and systems to develop innovative and miniaturized biochips for sensing at the molecular level. However, microelectronic biochips proposed in the literature often do not show the right specificity, sensitivity, and reliability required by biomedical applications. Nanotechnology offers new materials and solutions to improve the surface properties of sensing probes. The aim of the present paper is to review the most recent progress in Nano-Bio-Technology in the area of the development of new electrochemical systems for molecular detection in personalized therapy and cell culture monitoring.LSI
Overview of H-Mode Studies in Diii-D
No full textA major portion of the DIII-D program includes studies of the L-H transition, of the VH-mode, of particle transport and control and of the power-handling capability of a divertor. Significant progress has been made in all of these areas and the purpose of this paper is to summarize the major results obtained during the last two years. An increased understanding of the origin of improved confinement in H-mode and in VH-mode discharges has been obtained, good impurity control has been achieved in several operating scenarios, studies of helium transport provide encouraging results from the point of view of reactor design, an actively pumped divertor chamber has controlled the density in H-mode discharges and a radiative divertor is a promising technique for controlling the heat flux from the main plasma.CRPPSPCSuppl.
Microstructural alterations in the brain of well treated HIV+ patients with minor neurocognitive disorders: a multi-contrast study at high field
No full textLTS5CIB
Photoinduced oxidation of N-vinylcarbazole in a functionalized oil-in-water microemulsion
No full textThe photoprocesses of N-vinylcarbazole (NVC) solubilized in the interior of an oil-in-water microemulsion (CTA-ci, hexadecyltrimethylammonium counter ion) functionalized by an oxidizing agent, S2O2−8, were studied using ruby laser and spectrofluorimeter techniques. It was found that the excited singlet state of NVC reacts quickly with the persulfate to form its radical cation, exhibiting absorption maxima at 790, 700, 630 and 500 nm. Upon increasing the concentration of NVC substrate, a shift is observed in the absorption maximum of the cation at 790—770 nm, indicative of the formation of a dimer cation, (NVC)+2. This formation is further upheld by the augmentation of the decay rate of the cation with increasing substrate concentration.LP
Fatigue performance of a cold-curing structural epoxy adhesive subjected to moist environments
No full textThis paper presents the results of an experimental program designed to study the effects of aging and a wet environment on the fatigue behavior of epoxy resins used in bridge applications. Specimens were manufactured, cured, and treated, before the experiments, under a variety of conditions, in room and in water environments, in order to simulate the aging of adhesives in bridges for a period of up to 100 years. Experimental results indicated that a typical power law S-N equation could describe the fatigue stress vs. life behavior of the examined material under different gravimetric conditions. The slope of the curve was found to be in the range of that of other polymers and polymeric composite materials. The cyclic strain behavior and hysteresis loops were obtained under different gravimetric conditions and at different stress levels and the effects of both parameters on the viscoelastic behavior of the material have been thoroughly discussed. The fatigue failure surfaces were also recorded using a digital handheld microscope to reveal the damage mechanisms. The results of this work showed that the examined epoxy resin could sufficiently sustain fatigue loads with maximum cyclic stress levels of more than 25% of their quasi-static strength for more than 2 million cycles. (C) 2017 Elsevier Ltd. All rights reserved.CCLABGIS-G