Cherenkov mesons as in-medium quark energy loss

We recently showed that a heavy quark moving su ciently fast through a quark-gluon plasma may lose energy by Cherenkov-radiating mesons [1]. Here we review our previous holographic calculation of the energy loss in N = 4 Super Yang-Mills and extend it to longitudinal vector mesons and scalar mesons. We also discuss phenomenological implications for heavy-ion collision experiments. Although the Cherenkov energy loss is an O(1=Nc) effect, a ballpark estimate yields a value of dE/dx for Nc = 3 which is comparable to that of other mechanisms.

Cultura obrera y prensa anarquista: radiografia de Guerra di Classe, plataforma de los anarquistas italianos durante la Guerra Civil en Catalunya, 1936-1938

Giovanni C. Cattini is a young historian who offers an itemized study on Berneri's Guerra di Classe: he refers the first moments and also the definitive crisis of this newspaper after Berneri¿s assassination in May 1937. This is not the first work devoted to this militant platform has been annalysed but Cattini's approach observes not only the ideological and political contest maintained with other sectors of the libertarian movement but the contrived militant tools that have allowed its existance during the Spanish Civil War.

Cultura obrera y prensa anarquista: radiografia de Guerra di Classe, plataforma de los anarquistas italianos durante la Guerra Civil en Catalunya, 1936-1938

Giovanni C. Cattini is a young historian who offers an itemized study on Berneri's Guerra di Classe: he refers the first moments and also the definitive crisis of this newspaper after Berneri¿s assassination in May 1937. This is not the first work devoted to this militant platform has been annalysed but Cattini's approach observes not only the ideological and political contest maintained with other sectors of the libertarian movement but the contrived militant tools that have allowed its existance during the Spanish Civil War.

Casagrande, Massimo: Gli impiantianti di adduzione idrica romani in Byzacena e in Zeugitana, Studi di Storia Antica e di Archeologia 4, Nuove Grafiche Puddu, Ortacesus, 2008, 351 p.

La obra de Massimo Casagrande es altamente interesante por dos motivos. Por un lado, llena un vacío en los trabajos relativos al norte de África romano y, por otro lado, se integra en una corriente mundial de máxima actualidad: la visión holística y diacrónica de la hidráulica antigua. Esta tendencia en la investigación está siendo protagonizada de modo incuestionable a escala internacional por la profesora Ella Hermon (Université de Laval) y su «Chaire de recherche du Canada en interactions société - environnement natural dans l¿Empire romain». En España es obligatorio mencionar el Seminario Agustín de Horozco (Universidad de Cádiz) y su proyecto «Captación, usos y administración del agua en los municipios de la Bética romana».

LUGARESI, Leonardo, Il teatro di Dio. Il problema degli spettacoli nel cristianesimo antico (II-IV secolo), ed. Morcelliana, Brescia, 2008, 895 p., ISBN: 978-88-372-2257-4

La relación del cristianismo con los espectáculos de la tradición romano-pagana, y muy especialmente las críticas que los Padres de la Iglesia dirigieron a todo tipo de manifestación lúdica, constituye un tema complejo y lleno de interés que desde hace unos cuarenta años ha generado la publicación de importantes monografías consagradas a este sujeto. Sin duda, un momento de inflexión fue la aparición, en 1972, del célebre libro de Werner Weismann, Kirche und Schauspiele. Die Schauspiele im Urteil der lateinischen Kirchenväter unter besonderer Berücksichtigung vom Augustin. Posteriormente han visto la luz nuevos trabajos dedicados a examinar esta cuestión.

The structure of Mediterranean rocky reef ecosystems across environmental and human gradients, and conservation implications

Historical exploitation of the Mediterranean Sea and the absence of rigorous baselines makes it difficult to evaluate the current health of the marine ecosystems and the efficacy of conservation actions at the ecosystem level. Here we establish the first current baseline and gradient of ecosystem structure of nearshore rocky reefs at the Mediterranean scale. We conducted underwater surveys in 14 marine protected areas and 18 open access sites across the Mediterranean, and across a 31-fold range of fish biomass (from 3.8 to 118 g m22). Our data showed remarkable variation in the structure of rocky reef ecosystems. Multivariate analysis showed three alternative community states: (1) large fish biomass and reefs dominated by non-canopy algae, (2) lower fish biomass but abundant native algal canopies and suspension feeders, and (3) low fish biomass and extensive barrens, with areas covered by turf algae. Our results suggest that the healthiest shallow rocky reef ecosystems in the Mediterranean have both large fish and algal biomass. Protection level and primary production were the only variables significantly correlated to community biomass structure. Fish biomass was significantly larger in well-enforced no-take marine reserves, but there were no significant differences between multi-use marine protected areas (which allow some fishing) and open access areas at the regional scale. The gradients reported here represent a trajectory of degradation that can be used to assess the health of any similar habitat in the Mediterranean, and to evaluate the efficacy of marine protected areas.

Algas de una laguna salobre mediterranea (Lago di Patria, Napoles)

Lista de especies de algas identificadas en los ambientes salobres constituidos por el Lago di Patria, una laguna salobre próxima a Nápoles y diversas zanjas y charcas próximas. El conjunto de la flora y las comunidades son comparables a las que se encuentran en lagunas análogas de las costas francesa y española.

Tres argumentos para di/versificar as identidades de xénero: Arden, Pronomes e Lob*s

O noso propósito é presentar o proxecto máis ambicioso de poesía gai e lesbiana galega escrito, en paralelo, por Ana Romaní e Antón Lopo. A súa esculca poética representa unha interesante proposta de experimentación formal, na que se renova a concepción da poesía ó levala e adaptala a outros soportes, sen perder por iso a intensidade e a emoción lírica. Ademais ofrece dúas reflexións diferentes e complementarias sobre as identidades homosexuais, nas que se subliña o dereito a saír da sombra, a reivindicación do goce sexual (a arder e a ser lob*), e a definirse por posición e non pola imposición das convencións xenéricas (a rebeiión contra os pronomes).

Cherenkov mesons as in-medium quark energy loss

We recently showed that a heavy quark moving su ciently fast through a quark-gluon plasma may lose energy by Cherenkov-radiating mesons [1]. Here we review our previous holographic calculation of the energy loss in N = 4 Super Yang-Mills and extend it to longitudinal vector mesons and scalar mesons. We also discuss phenomenological implications for heavy-ion collision experiments. Although the Cherenkov energy loss is an O(1=Nc) effect, a ballpark estimate yields a value of dE/dx for Nc = 3 which is comparable to that of other mechanisms.