1,720,996 research outputs found
«Vivir no es tan importante como recordar»: "Memoria de la melancolía" di María Teresa León
No full textMaría Teresa León is one of the Spanish writers who lived the experience of exile for a long time. After Paris
and Buenos Aires, she arrived in Rome with her husband Rafael Alberti, and in the eternal city she lived until
1977. In Rome she wrote her autobiography Memoria de la melancolía, in which she tries to fix all her past
memories, as an antidote to desmemoria. This work is at the same time the intimate story of a woman who
loved her country and fought for its freedom, and a collective narrative of all those who shared the same tragic
experience – a work in which memory and writing join together to save the personal and collective past from
oblivion, with a slight hope for the future
Agustín Gómez Arcos e la libertà ritrovata tra francese e spagnolo
No full textAgustín Gómez Arcos, scrittore che ha scelto l'esilio per scappare dall'oppresione della censura franchista sulle sue opere, sceglie, una volta in Francia, di scrivere i suoi romanzi nella lingua d'accoglienza. In un paio di occasioni, però, decide di autotradursi, quasi di "riscrivere" la sua opera, per riuscire finalmente a parlare al pubblico dei suoi connazionali, che poco o niente lo conoscevano, e per riappropriarsi della sua identità spagnola, a partire dalla lingua
3β,5α,6β-Trihydroxylated sterols with a saturated nucleus from two populations of the marine sponge Cliona copiosa
No full textNEW STEROIDAL HYDROXYKETONES AND CLOSELY RELATED DIOLS FROM THE MARINE SPONGE CLIONA-COPIOSA
No full textDELTA5-3beta-Hydroxy-7-ketosteroids 1-7, DELTA5-3beta,7beta-dihydroxysterols 8-13, and DELTA5-3beta,7alpha-dihydroxysterols 14-17 were isolated from the sponge Cliona copiosa, and the structures were elucidated by spectroscopic methods and chemical correlation with known compounds
3-BETA,5-ALPHA,6-BETA-TRIHYDROXYLATED STEROLS WITH A SATURATED NUCLEUS FROM 2 POPULATIONS OF THE MARINE SPONGE CLIONA-COPIOSA
No full textTwo different populations of the marine sponges Cliona copiosa, collected in two different sites of the Mediterranean sea, were examined for polyoxygenated sterols. C. copiosa from the bay of Naples contained 5-alpha-cholestane-3-beta,5, 6-beta-triol [1] and the new trihydroxysterols (22E)-5-alpha-cholest-22-ene-3-beta,5,6-beta-triol [2], (22E,24S)-24-methyl-5-alpha-cholest-22-ene-3-beta,5,6-beta-triol [3], (22E,24R)-24-methyl-5-alpha-cholest-22-ene-3-beta,5,6-beta-triol [4], (24R)-24-ethyl-5-alpha-cholestane-3-beta,5,6-beta-triol [5], and (24S)-24-ethyl-5-alpha-cholestane-3-beta,5,6-beta-triol [6]. The population collected from Marsala lagoon, Sicily, contained only sterols 1, 5, and 6. The structures of these compounds were deduced by analysis of spectral data. Partial synthesis of compounds 1, 5, and 6 confirmed the structure assignmen
STRUCTURE AND ABSOLUTE-CONFIGURATION OF 2 NEW POLYBROMINATED-C15 ACETOGENINS FROM THE SPONGE MYCALE-ROTALIS
No full textThe structure and absolute configuration of two CI5 polybrominated acetogenins 1 and 2, isolated from Mycale
rotalis, have been determined by a combination of spectroscopic and X-ray diffraction analyses and through the
chemical interconversion of 1 to 2; biosynthetic relationship between 1 and 2 is postulated
Equivalent oscillator approach to model vortex induced vibrations on a circular cylinder
Full text linkThe paper presents a numerical model, based on the equivalent oscillator approach, able to simulate vortex induced vibrations on a circular cylinder. This model consists of a single degree of freedom mechanical system characterized by non-linear parameters that reproduce the fluid-structure interaction in time domain. A genetic algorithm approach was used in order to identify the characteristic parameters of the equivalent oscillator: obtained results are discussed and compared with wind tunnel experimental data and with a previous version of the numerical model. Comparison is performed both in terms of aerodynamic forces and oscillation amplitudes and both in steady and transient conditions
SYNTHESIS OF THE MARINE EPOXY STEROL 9-ALPHA,11-ALPHA-EPOXY-5-ALPHA-CHOLEST-7-ENE-3-BETA,5,6-BETA-TRIOL
No full textThe synthesis of 9-alpha, 11-alpha-epoxy-5-alpha-cholest-7-ene-3-beta,5,6-beta-triol(1), a a highly oxygenated marine sterol containing a 9,11-epoxide moiety in the nucleus, is described. Epoxy sterol 1 was synthesized from cholesta-5,7-dien-3-beta-ol. Oxidation of this sterol with m-chloroperbenzoic acid followed by hydrolysis and acetylation furnished 5-alpha-cholesst-7-ene-3-beta,5, 6-alpha-triol 3,6-diacetate (2). Mercuric acetate dehydrogenation of diacetate 2, followed by oxidation with manganese dioxide and epoxidation with m-chloroperbenzoic acid, afforded 9-alpha,11-alpha-epoxy-3-beta, 5-alpha-cholest-7en-6-one (5). Reduction of 5 with lithium aluminum hydride gave the desired compound 1. The structures of all synthetic intermediates were confirmed by H-1 and C-13 nuclear magnetic resonance (NMR) spectroscopy. A reassignment of resonances for carbons 1, 8, and 15 in the C-13 NMR spectrum of 1, based on 2D-NMR correlation spectroscopy, has been accomplishe
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