Suchergebnisse

10 páginas.- 4 figuras.- referencias.-Data Availability Statement: All data underlying this article are available in the main publication and in its Supplementary Materials online. ; Unspecific peroxygenases (UPOs), the extracellular enzymes capable of oxygenating a potpourri of aliphatic and aromatic substrates with a peroxide as co-substrate, come out with a new reaction: carbon-chain shortening during the conversion of fatty acids with the well-known UPOs from Coprinopsis cinerea (rCciUPO) and Cyclocybe (Agrocybe) aegerita (AaeUPO). Although a pathway (Cα-oxidation) for shortening the hydrocarbon chain of saturated fatty acids has already been reported for the UPO from Marasmius rotula (MroUPO), it turned out that rCciUPO and AaeUPO shorten the chain length of both saturated and unsaturated fatty acids in a different way. Thus, the reaction sequence does not necessarily start at the Cα-carbon (adjacent to the carboxyl group), as in the case of MroUPO, but proceeds through the subterminal (ω-1 and ω-2) carbons of the chain via several oxygenations. This new type of shortening leads to the formation of a dicarboxylic fatty acid reduced in size by two carbon atoms in the first step, which can subsequently be further shortened, carbon by carbon, by the UPO Cα-oxidation mechanism. View Full-Text ; This research was funded by BioBased Industries Joint Undertaking under the European Union's Horizon 2020 Research and Innovation Programme, grant number 792063 (SusBind project; https://susbind.eu; to A.G., Á.T.M. and M.H.), the PID2020-118968RB-100 project by the Spanish MCIN/AEI/ 10.13039/501100011033 to A.G., and the CSIC projects PIE-202040E185 (to A.G.) and PIE-202120E019 (to Á.T.M.). ; Peer reviewed

At the end of the 1870s, the oppressive policies of the Argentine State were intensified towards the indigenous people linked to the Southern Border, visible in the punitive expeditions of 1878-1879. In the case of theranqueles, located in the centralPampa, these actions were part of previous strategies of attrition, carried out by the military commanders ofSan LuisandCórdobathrough the diplomatic channel, softening campaigns and co-optation of contingents who, both forced and voluntarily, migrated to the fortsVilla MercedesandSarmiento. From a line of investigation that seeks to reconstruct the itineraries of theranquelessubmitted in the aforementioned context, the article characterizes the imprisonment of the indigenous people taken by the 3rd Expeditionary Division (April-August 1879) under the leadership of Colonel Eduardo Racedo. Its purpose is to describe their living conditions while they were in thePitral Lauquencamp (nearPoitagué), understanding that it simultaneously acted as a place of concentration and distribution of prisoners. ; Al terminar la década de 1870 se intensificaron las políticas opresivas del Estado argentino para con los indígenas ligados a la Frontera Sur, visibles en las expediciones punitivas de 1878-1879. En el caso de los ranqueles, situados en la pampa central, estas acciones se enmarcan en estrategias previas de desgaste ejecutadas por los mandos militares de San Luis y Córdoba a través de la vía diplomática, las campañas de ablandamiento y cooptación de contingentes que migrabande manera forzaday por presentación a los fuertes Villa Mercedes y Sarmiento. Desde una línea de investigación que busca reconstruir los itinerarios de los ranqueles sometidos en ese contexto, el artículo caracteriza elaprisionamiento de los indígenas tomados por la 3aDivisión Expedicionaria (abril-agosto de 1879) bajo el liderazgo del coronel Eduardo Racedo. Su finalidad es describir sus condiciones de vida mientras estuvieron depositados en el campamento Pitral Lauquen (cercano a Poitagué), lugar de concentración y distribución de prisioneros.

International audience ; Although nuclear energy forms an important and controversial part of polar history, its uses and misuses have so far received little attention from professional historians. Especially mobile nuclear reactors, as deployed for instance on the Antarctic continent, played an important role in the conquest of the polar regions. The Antarctic case presented here allows to illustrate the large diversity of issues involved in the American mobile nuclear reactor programme, ranging from economic considerations, over military strategy, to environmental and health concerns. During several decades, mobile nuclear power reactors were considered a cheap and clean solution, yet as this essay shows, history proved otherwise. None of the economic targets were met and in the case of the Antarctic reactor, repeated failures and even radioactive leakages lead finally to the shutdown of the whole programme. ; Même si l'énergie nucléaire joue un rôle important et controversé dans l'histoire polaire, son usage et son mésusage ont reçu très peu d'attention de la part des historiens. Les réacteurs nucléaires mobiles en particulier, tels qu'ils ont été mis en oeuvre sur le continent antarctique, ont occupé une fonction cruciale dans la conquête des régions polaires. Le cas antarctique présenté ici permet d'illustrer la grande diversité des éléments invoqués dans le programme étatsunien de réacteurs nucléaires mobiles, allant de considérations économiques, en passant par la stratégie militaire, à des inquiétudes environnementales et de santé publique. Pendant plusieurs décennies, les réacteurs nucléaires mobiles ont été considérés une solution peu couteuse et propre, mais comme nous allons arguer ci-dessous, l'histoire en a voulu autrement. Aucun des objectifs économiques ne fut atteint et dans le cas du réacteur en Antarctique, de nombreuses coupures et même des fuites radioactives ont amené enfin à l'abandon du programme.