Evolution of Black Holes in the Galaxy

In this article we consider the formation and evolution of black holes, especially those in binary stars where radiation from the matter falling on them can be seen. We consider a number of effects introduced by some of us, which are not traditionally included in binary evolution of massive stars. These are (i) hypercritical accretion, which allows neutron stars to accrete enough matter to collapse to a black hole during their spiral-in into another star. (ii) the strong mass loss of helium stars, which causes their evolution to differ from that of the helium core of a massive star. (iii) The direct formation of low-mass black holes (M\sim2\msun) from single stars, a consequence of a significant strange-matter content of the nuclear-matter equation of state at high density. We discuss these processes here, and then review how they affect various populations of binaries with black holes and neutron stars.Comment: 46 pages, 1 figure, to be published in Physics Repor

Diversity, host specialization, and geographic structure of filarial nematodes infecting Malagasy bats

We investigated filarial infection in Malagasy bats to gain insights into the diversity of these parasites and explore the factors shaping their distribution. Samples were obtained from 947 individual bats collected from 52 sites on Madagascar and representing 31 of the 44 species currently recognized on the island. Samples were screened for the presence of micro-and macro-parasites through both molecular and morphological approaches. Phylogenetic analyses showed that filarial diversity in Malagasy bats formed three main groups, the most common represented by Litomosa spp. infecting Miniopterus spp. (Miniopteridae); a second group infecting Pipistrellus cf. hesperidus (Vespertilionidae) embedded within the Litomosoides cluster, which is recognized herein for the first time from Madagascar; and a third group composed of lineages with no clear genetic relationship to both previously described filarial nematodes and found in M. griveaudi, Myotis goudoti, Neoromicia matroka (Vespertilionidae), Otomops madagascariensis (Molossidae), and Paratriaenops furculus (Hipposideridae). We further analyzed the infection rates and distribution pattern of Litomosa spp., which was the most diverse and prevalent filarial taxon in our sample. Filarial infection was disproportionally more common in males than females in Miniopterus spp., which might be explained by some aspect of roosting behavior of these cave-dwelling bats. We also found marked geographic structure in the three Litomosa clades, mainly linked to bioclimatic conditions rather than host-parasite associations. While this study demonstrates distinct patterns of filarial nematode infection in Malagasy bats and highlights potential drivers of associated geographic distributions, future work should focus on their alpha taxonomy and characterize arthropod vectors

Developments in hydrology of mountainous areas

This report is simultaneously the annual report n°4 of the AMHY Group of FRIEND, and this of the UNESCO IHP IV project n° H-5-6 named "Hydrology of mountaineous areas". It deals with several aspects of regional hydrology in mountains (AMHY and H-5-6), in mediterranean regions (AMHY) and in Carpathes (H-5-6). It represents also the proceedings of the Stara Lesna (Slovaquia) meeting in 1994." / Ce document est à la fois le rapport annuel n°4 du Groupe AMHY de FRIEND et le compte-rendu d'un petit projet de l'Unesco dit "Hydrologie de montagne" (projet numéroté H-5-6 dans le PHI IV). Il traite de divers aspects de l'hydrologie régionale en zone alpine et méditerranéenne (partie AMHY), et des spécificités de l'hydrologie des Carpathes (partie H-5-6). Il rend compte des travaux réalisés dans le Groupe AMHY durant l'année 1994-95, et des communications présentées à la réunion annuelle 1994 de Stara Lesna (Slovaquie)