Search results for "LENI"
showing 10 items of 756 documents
Low dose splenic irradiation in myelofibrosis: outcomes and toxicity of three radiation schedule
2009
Spontaneous rupture of splenic artery aneurysm in pregnancy: is splenectomy always necessary?
2012
Letter to Editor
Robust dynamic cooperative games
2009
Classical cooperative game theory is no longer a suitable tool for those situations where the values of coalitions are not known with certainty. Recent works address situations where the values of coalitions are modelled by random variables. In this work we still consider the values of coalitions as uncertain, but model them as unknown but bounded disturbances. We do not focus on solving a specific game, but rather consider a family of games described by a polyhedron: each point in the polyhedron is a vector of coalitions’ values and corresponds to a specific game. We consider a dynamic context where while we know with certainty the average value of each coalition on the long run, at each t…
Selenium Imides: 77Se NMR Investigations of the SeCl2−tBuNH2 Reaction and X-ray Structures of Se3(NtBu)3, tBuNSe(μ-NtBu)2SO2, and tBuNSe(μ-NtBu)2SeO
2000
The reaction of SeCl2 with tert-butylamine in various molar ratios in THF at −78 °C has been investigated by 77Se NMR spectroscopy. In addition to the known Se−N heterocycles Se6(NtBu)2 (1) and Se9(NtBu)6 (2), the acyclic imidoselenium(II) dichlorides ClSe[N(tBu)Se]nCl (4, n = 1; 5, n = 2) and two new cyclic selenium imides [Se3(NtBu)2]n (3, n = 1 or 2) and Se3(NtBu)3 (6) have been isolated and identified. An X-ray analysis shows that 6 is a six-membered ring in a chair conformation with |d(Se−N)| = 1.833 A. Crystal data: 6, trigonal, P3c1, a = 9.8660(3) A, c = 20.8427(7) A, V = 1757.0(1) A3, Z = 6. The 1H, 13C, and 77Se NMR data for 1−6 are reported, and some reassignments of earlier lite…
Composés métallocèniques chalcogènés. Action des dihydrures de zirconocène et de hafnocène sur le soufre, le sélénium et le tellure
1989
Resume Dimeric zirconocene and hafnocene dihydrides [(η 5 -RC 5 H 4 ) 2 M(H)(μ-H)] 2 (M = Zr, Hf) react with grey selenium or tellurium to afford the known four-membered bimetallacyclic compounds [(η 5 -RC 5 H 4 ) 2 M(μ-E)] 2 (E = Se, Te) as the sole organometallic products. In the case of sulfur the first step of the reaction is shown to involve the insertion of a chalcogen atom into the metal-hydrogen bonds to give the bis-hydrogenosulfide (η 5 -t-BuC 5 H 4 ) 2 M(SH) 2 (M = Zr, Hf), which reacts either with the starting dihydride to give [(η 5 -t-BuC 5 H 4 ) 2 M(μ-S)] 2 or with the unchanged sulfur to afford the metallacyclohexasulfane (η 5 -t-BuC 5 H 4 ) 2 MS 5 and hydrogen sulfide. Thes…
Veniet Tempus (QNat.7.25): Stoic Philosophy and Roman Genealogy in Seneca's View of Scientific Progress
2014
Seneca's views on the future development of knowledge have often been interpreted as an enlightened anticipation of the modern faith in progress. And Seneca himself has been depicted as a sort of Condorcet avant la lettre. In the present paper, I argue that while it is extremely interesting to investigate the reception of Senecan patterns in modern thought, the writer's idea of scientific and moral enhancement should primarily be understood in the intellectual and socio-anthropological framework of ancient culture. Indeed, a reassessment of the evidence offered by the Natural Questions and the Moral Epistles shows that Seneca devises a broadly conceived spectrum of progress, which reflects …
Chalcogenide-capped triiron clusters [Fe3(CO)9(μ3-E)2], [Fe3(CO)7(μ3-CO)(μ3-E)(μ-dppm)] and [Fe3(CO)7(μ3-E)2(μ-dppm)] (E = S, Se) as proton-reduction…
2019
Chalcogenide-capped triiron clusters [Fe3(CO)7(μ3-CO)(μ3-E)(μ-dppm)] and [Fe3(CO)7(μ3-E)2(μ-dppm)] (E = S, Se) have been examined as proton-reduction catalysts. Protonation studies show that [Fe3(CO)9(μ3-E)2] are unaffected by strong acids. Mono-capped [Fe3(CO)7(μ3-CO)(μ3-E)(μ-dppm)] react with HBF4.Et2O but changes in IR spectra are attributed to BF3 binding to the face-capping carbonyl, while bicapped [Fe3(CO)7(μ3-E)2(μ-dppm)] are protonated but in a process that is not catalytically important. DFT calculations are presented to support these protonation studies. Cyclic voltammetry shows that [Fe3(CO)9(μ3-Se)2] exhibits two reduction waves, and upon addition of strong acids, proton-reducti…
Ceci c'est la pipe: come si racconta l'assedio di Leningrado
2017
L'assegnazione del premio Nobel a Svetlana Aleksievič è stata interpretata da più parti come un atto di canonizzazione della letteratura non-fiction, e spesso come una prova della caduta definitiva delle barriere tra letteratura e giornalismo. Aleksievič ha però alle spalle, nella letteratura sovietica, una tradizione che, se non è definitivamente codificata, risale però probabilmente fino agli anni Trenta e, soprattutto a partire dal dopoguerra, presenta una consistenza niente affatto trascurabile. L'analisi comparata di un testo del maestro dichiarato di Aleksievič, Ales' Adamovič, la Blokadnaja kniga (scritta a quattro mani con Daniil Granin) e della più canonica delle opere letterarie s…
Early–middle Jurassic lytoceratid ammonites with constrictions from Morocco: palaeobiogeographical and evolutionary implications.
2008
13 pages; International audience; The ammonite genus Alocolytoceras Hyatt, 1900 is an uncommon lytoceratid with distinctive shell ornament. A set of 58 specimens, recently collected at Amellago in the central High Atlas (Morocco), has enabled us to trace a succession of three species over eight biozones from the Toarcian to the Aalenian. Two specimens from the Lusitanian Basin are added for comparison. Following a review of the genus, based on original specimens and data from the literature, seven species are considered valid. A palaeobiogeographical synthesis of 13 regions demonstrates irregular distribution patterns over time, with a constant presence in the south-west Tethys and an insta…
Ksiądz prymas Stefan Wyszyński na uroczystościach milenijnych w Opolu i Kamieniu Śląskim (13-14 sierpnia 1966 r.) - historia i aktualność przesłania
2022
W dniach 13 i 14 sierpnia 1966 r. ks. prymas Stefan Wyszyński wziął udział w uroczystościach liturgicznych w Opolu i Kamieniu Śląskim w ramach obchodów milenium chrztu w Polsce. Wygłosił wtedy kazania w Opolu 13 i 14 sierpnia, a także 14 sierpnia w Kamieniu Śląskim. Zaangażowanie ówczesnych lokalnych władz, milicji czy Służby Bezpieczeństwa w niwelowanie znaczenia tych obchodów, a zarazem treść przesłania, z jakim do swoich rodaków zwrócił się w Opolu i Kamieniu Śląskim z 1966 r. prymas Wyszyński, dowodzą, że trudno było pozostać obojętnym wobec tego nauczania. Chociaż uwarunkowania społeczno-polityczne zmieniły się, postać prymasa i jego nauczanie wciąż inspirują. Artykuł pt. Ksiądz prymas…