Tertiary Alcohols as Radical Precursors for the Introduction of Tertiary Substituents into Heteroarenes

Despite many recent advances in the radical alkylation of electron-deficient heteroarenes since the seminal reports by Minisci and co-workers, methods for the direct incorporation of tertiary alkyl substituents into nitrogen heteroarenes are limited. This report describes the use of tert-alkyl oxalate salts, derived from tertiary alcohols, to introduce tertiary substituents into a variety of heterocyclic substrates. This reaction has reasonably broad scope, proceeds rapidly under mild conditions, and is initiated by either photochemical or thermal activation. Insights into the underlying mechanism of the higher yielding visible-light initiated process were obtained by flash photolysis studies, whereas computational studies provided insight into the reaction scope

A Multistage Method for SCMA Codebook Design Based on MDS Codes

Sparse Code Multiple Access (SCMA) has been recently proposed for the future generation of wireless communication standards. SCMA system design involves specifying several parameters. In order to simplify the procedure, most works consider a multistage design approach. Two main stages are usually emphasized in these methods: sparse signatures design (equivalently, resource allocation) and codebook design. In this paper, we present a novel SCMA codebook design method. The proposed method considers SCMA codebooks structured with an underlying vector space obtained from classical block codes. In particular, when using maximum distance separable (MDS) codes, our proposed design provides maximum signal-space diversity with a relatively small alphabet. The use of small alphabets also helps to maintain desired properties in the codebooks, such as low peak-to-average power ratio and low-complexity detection.Comment: Submitted to IEEE Wireless Communication Letter

A mid-IR study of Hickson Compact Groups II. Multi-wavelength analysis of the complete GALEX-Spitzer Sample

We present a comprehensive study on the impact of the environment of compact galaxy groups on the evolution of their members using a multi-wavelength analysis, from the UV to the infrared, for a sample of 32 Hickson compact groups (HCGs) containing 135 galaxies. Fitting the SEDs of all galaxies with the state-of-the-art model of da Cunha (2008) we can accurately calculate their mass, SFR, and extinction, as well as estimate their infrared luminosity and dust content. We compare our findings with samples of field galaxies, early-stage interacting pairs, and cluster galaxies with similar data. We find that classifying the groups as dynamically "old" or "young", depending on whether or not at least one quarter of their members are early-type systems, is physical and consistent with past classifications of HCGs based on their atomic gas content. [...ABRIDGED...] We also examine their SF properties, UV-optical and mid-IR colors, and we conclude that all the evidence point to an evolutionary scenario in which the effects of the group environment and the properties of the galaxy members are not instantaneous. Early on, the influence of close companions to group galaxies is similar to the one of galaxy pairs in the field. However, as the time progresses, the effects of tidal torques and minor merging, shape the morphology and star formation history of the group galaxies, leading to an increase of the fraction of early-type members and a rapid built up of the stellar mass in the remaining late-type galaxies.Comment: Accepted for publication in A&A. Figure resolution degraded for arXiv limits, full resolution paper available at http://www.physics.uoc.gr/~bitsakis/paperII_bitsakis.pd

La prise en charge des personnes âgées dépendantes en France et en Italie. Familialisation ou défamilialisation du care ?

Chaque système de protection sociale repose sur un équilibre spécifique entre les responsabilités collectives et les responsabilités familiales par rapport aux risques sociaux et aux besoins de care. Dans un contexte de vieillissement de la population et de diminution du nombre d’aidants potentiels disponibles, il est intéressant de s’interroger sur les alternatives proposées par les gouvernements et sur la portée des politiques qui se dessinent depuis la fin des années 1990. Quelle articulation entre l’aide familiale et l’intervention publique ? L’analyse porte sur la situation dans deux pays, l’Italie et la France, où la famille joue traditionnellement un rôle important dans la prise en charge des personnes âgées dépendantes. Elle montre dans les deux pays un phénomène d’externalisation du care grâce au développement de dispositifs de cash for care, mais selon des modalités différentes. Dans un cas comme dans l’autre, cela ne signifie pas pour autant qu’il y ait défamilialisation du care. On assiste plutôt à une transformation des pratiques de care.Every social welfare system is based on a specific balance between collective and family responsibility for social risks and care needs. In the context of an aging population and a dwindling number of potential family carers, it is worthwhile taking a look at the alternatives being proposed by governments and at the scope of the policies adopted since the late 1990s. What is the relationship between family provision and public intervention ? Our analysis explores the situation in Italy and France, two countries where the family traditionally plays a major role in caring for the dependant elderly. It points to a trend in both countries toward an externalization of care through the development of cash-for-care systems, but with different modes of implementation. In neither case, however, does this mean a defamilialization of care but involves, rather, a transformation of care practices

Comparison of energy consumption and costs of different HEVs and PHEVs in European and American context

This paper will analyse on the one hand the potential of Plug in Hybrid electric Vehicles to significantly reduce fuel consumption and displace it torward various primary energies thanks to the electricity sector. On the other hand the total cost of ownership of two different PHEV architectures will be compared to a conventional cehicle and a HEV without external charging

On the equivalence of the self-dual and Maxwell-Chern-Simons models coupled to Fermions

We study the exact equivalence between the self-dual model minimally coupled with a Dirac field and the Maxwell-Chern-Simons model with non-minimal magnetic coupling to fermions. We show that the fermion sectors of the models are equivalent only if a Thirring like interaction is included. Using functional methods we verify that, up to renormalizations, the equivalence persists at the quantum level.Comment: 8 pages, revte