Determination of Z/β for strange quark matter candidates with CR-39 track detector

In order to confirm the existence of strange quark matter (SQM) in cosmic rays, a series of international balloon flights with a hybrid system combining active counters and passive detectors was conducted under the collaboration between Japan and Italy. In this report, the methodology of how to detect SQM with the hybrid system and how to determine Z/β with CR-39 track detectors are presented.     

Evaluating the Effect of four Hosting Ionophores on the Performance of Anion Selective Potentiometric Sensor

A systematically designed practical approach was carried out for the optimization of an anion selective electrode for the determination of an anionic laxative, docusate sodium (DS). The PVC membrane composition and the sensor assembly were systematically optimized. Different sensors were fabricated using tetradodecylammonium bromide (TDAB), tridodecylmethylammonium bromide, tetraheptylammonium bromide as ion exchangers. The effect of ionophore was evaluated using four different host‐guest ionophores, namely; calix[8]arene, β‐cylodextrin, hydroxypropyl‐β‐cylodextrin and carboxymethyl‐β‐cylodextrin to reach the optimum membrane composition. Sensors were constructed in both liquid membrane and solid contact sensor‐assemblies. The slope, linear range, LOQ and response time for each sensor was calculated to assess their performance characteristics. Best Nernstian slope of ?61.38 mV/decade and lowest quantification limit of 7.62×10^?7 M was achieved by the sensor containing TDAB as ion exchanger and Calix[8]arene as ionophore in the PVC matrix using the gold wire solid contact sensor assembly. Electrode selectivity was assured in the presence of DS potential degradation product, common interfering ions and industrial excipients of tablet and gel formulations. Validation was carried out regarding the ICH validation parameters.     

Telescoped,Divergent, Chemoselective C1 and C1‐C1 Homologation of Imine Surrogates: Access to Quaternary Chloro‐ and Halomethyl‐Trifluoromethyl Aziridines

A conceptually novel, high‐yielding, mono‐ or bis‐homologation was realized with lithium halocarbenoids and enables the one‐step, fully chemocontrolled assembly of a new class of quaternary trifluoromethyl aziridines. Trifluoroacetimidoyl chlorides (TFAICs) act as convenient electrophilic platforms, enabling the addition of either one or two homologating elements by simply controlling the stoichiometry of the process. Mechanistic studies highlighted that the homologation event, carried out with two different carbenoids (LiCH₂Cl and LiCH₂F), leads to fluoromethyl analogues in which the first nucleophile is employed for constructing the cycle and the second for decorating the resulting molecular architecture.     

14-Acetylandrographolide

The title compound, 3-{2-[decahydro-6-hydroxy-5-(hydroxymethyl)-5,8a-dimethyl-2-methylene-1-napthalenyl]ethylidene}dihydro-4-acetoxy-2(3H)-furanone, C₂₂H₃₂O₆, was synthesised from andrographolide. It crystallizes in the orthorhombic system with a = 7.4219(12), b = 11.8411(10), c = 23.777(4) Å in space group P2₁2₁2₁. While the stereochemical relation between rings is slightly changed from the starting material, acetylation of the hydroxyfuranone moiety completely abolishes O--HO hydrogen bonding there, leaving a C--HO interaction. The hydrogen-bonded chains at the opposite end of the andrographolide molecule persist but reverse direction.     

Data completion for the Stokes system

This Note is concerned with the severely ill-posed Cauchy–Stokes problem. This inverse problem is rephrased into an optimization one: An energy-like error functional is introduced. We prove that the optimality condition of the first order is equivalent to solving an interfacial equation which turns out to be a Cauchy–Steklov–Poincaré operator. Numerical trials highlight the efficiency of the present method. To cite this article: A. Ben Abda et al., C. R. Mecanique 337 (2009).     

A fault tolerant routing scheme for hypercubes

An efficient distributed fault‐tolerant routing algorithm for the hypercube is proposed based on the existence of a complete set of node‐disjoint paths between any two nodes. Node failure and repairs may occur dynamically provided that the total number of faulty nodes at any time is less than the node‐connectivity n of the n‐cube. Each node maintains for each possible destination which of the associated node‐disjoint paths to use. When a message is blocked by a node failure, the source node is warned and requested to switch to a different node‐disjoint path. The methods used to identify the paths, to propagate node failure information to source nodes, and to switch from one routing path to another incur little communication and computation overhead. We show that if the faults occur reasonably apart in time, then all messages will be routed on optimal or near optimal paths. In the unlikely case where many faults occur in a short period, the algorithm still delivers all messages but via possibly longer paths. An extension of the obtained algorithm to handle link failures in addition to node failures is discussed. We also show how to adapt the algorithm to n‐ary n‐cube networks. The algorithm can be similarly adapted to any interconnection network for which there exists a simple characterization of node‐disjoint paths between its nodes. This revised version was published online in June 2006 with corrections to the Cover Date.     

Characterization and evaluation of TCP and UDP-based transport on real networks

StandardTcp (RenoTcp) does not perform well on fast long distance networks, due to its AMD congestion control algorithm. In this paper we consider the effectiveness of various alternatives, in particular with respect to their applicability to a production environment. We then characterize and evaluate the achievable throughput, stability and intra-protocol fairness of differentTcp stacks (Scalable,Hstcp,Htcp, FastTcp, Reno,Bictcp, hstcp-lp andLtcp) and aUdp based application level transport protocol (Udtv2) on both production and testbed networks. The characterization is made with respect to both the transient traffic (entry and exit of different streams) and the steady state traffic on production Academic and Research networks, using paths withRtts differing by a factor of 10. We also report on measurements made with 10 Gbit/secNics with and withoutTcp Offload Engines, on 10 Gbit/s dedicated paths set up forSc2004.     

Existence and Uniqueness of Traveling Waves for Fully Overdamped Frenkel–Kontorova Models

In this article, we study the existence and the uniqueness of traveling waves for a discrete reaction–diffusion equation with bistable nonlinearity, namely a generalization of the fully overdamped Frenkel–Kontorova model. This model consists of a system of ODEs which describes the dynamics of crystal defects in lattice solids. Under very weak assumptions, we prove the existence of a traveling wave solution and the uniqueness of the velocity of propagation of this traveling wave. The question of the uniqueness of the profile is also studied by proving Strong Maximum Principle or some weak asymptotics on the profile at infinity.     

Robustness of Entangled Squeezed States Versus Entangled Coherent States Against Channel Decoherence Effect

We compare theoretically the effects of channel decoherence on entangled coherent states (ECSs) and entangled squeezed states (ESSs) as non-orthogonal states. The comparison is achieved in the case when the interaction with the noisy environment is symmetric and when it is asymmetric. In the first case, we notice a robustness of ECSs compared with ESSs against the photons losses. This robustness increases with a good way after using a higher amplitudes. However, in the asymmetric decoherence case, the ESSs resist more the photon losses compared with the ECSs.     

Un modèle générique multi-niveaux pour la recherche d’image par le contenu

In this paper we propose a generic model for content image modelling. The model is based on several levels of information. Each level is called view and relates to a class of information. We distinguish three types of views: the concept, relation and interpretation views. The view concept or relation makes it possible to define respectively the concepts or the calculable relations automatically that do not require any particular interpretation. The view interpretation relates to the interpretation of the contents of the image. The number, the nature and the contents of each view are adaptable and can vary according to the type of application. The operational model is based on the nested conceptual graphs which we extended. The model is implemented and operational and the results obtained are very encouraging.