Siliceous deep-sea sponge Monorhaphis chuni: A potential paleoclimate archive in ancient animals

The deep-sea sponge Monorhaphis chuni forms giant basal spicules, which can reach lengths of 3 m; they represent the largest biogenic silica structures on Earth that is formed from an individual metazoan. The spicules offer a unique opportunity to record environmental change of past oceanic and climatic conditions. A giant spicule collected in the East China Sea in a depth of 1110 m was investigated. The oxygen isotopic composition and Mg/Ca ratios determined along center-to-surface segments are used as geochemical proxies for the assessment of seawater paleotemperatures. Calculations are based on the assumption that the calculated temperature near the surface of the spicule is identical with the average ambient temperature of 4 degrees C. A seawater temperature of 1.9 degrees C is inferred for the beginning of the lifespan of the Monorhaphis specimen. The temperature increases smoothly to 2.3 degrees C, to be followed by sharply increased and variable temperatures up to 6-10 degrees C. In the outer part of the spicule, the inferred seawater temperature is about 4 degrees C. The lifespan of the spicule can be estimated to 11,000 +/- 3000 years using the long-term trend of the inferred temperatures fitted to the seawater temperature age relationships since the Last Glacial Maximum. Specimens of Monorhaphis therefore represents one the oldest living animals on Earth. The remarkable temperature spikes of the ambient seawater occurring 9500-3100 years B.P. are explained by discharges of hydrothermal fluids in the neighborhood of the spicule. The irregular lamellar organization of the spicule and the elevated Mn concentrations during the high-temperature growth are consistent with a hydrothermal fluid input. (C) 2012 Elsevier B.V. All rights reserved.

The Hindu Model of Social Organization and the bhakti Movement : the Example of Vallabha's sampradāya

(Résumé de l'ouvrage) This volume addresses research topics within the field of Bhakti literature, the devotional poetry and other compositions of devotional character in the earlier literature of the modern South Asian languages. Its papers range from the roots of the Bhakti tradition in the early history of Krsna to its modern adaptations in nineteenth- and twentieth-century culture. Geographically, they span Bengal to Sind, Panjab to Maharashtra. Contemporary study of the modern Indian languages has broadened the scope of scholarship to consider today's Hindu attitudes, and those of a mixed society, against the background of ancient culture. Here, materials in six modern Asian languages are discussed: Bengali, Gujarati, Hindi in its main literary forms, Marathi, Panjabi and Sindhi; with assessment also of material in Sanskrit, Arabic and Chinese. In addition to studies of literary (and orally transmitted) works in the Krsna or Rama traditions, and of Sufi compositions and their interpretation, there are papers on the early history of sacred sites, the emergence of the religion of Rama, later religious formulations throughout the subcontinent, and the interaction of the Islamic and the Hindu.

The First Christian Historian. Writing the "Acts of the Apostles"

As the first historian of Christianity, Luke's reliability is vigorously disputed among scholars. The author of the Acts is often accused of being a biased, imprecise, and anti-Jewish historian who created a distorted portrait of Paul. Daniel Marguerat tries to avoid being caught in this true/false quagmire when examining Luke's interpretation of history. Instead he combines different tools - reflection upon historiography, the rules of ancient historians and narrative criticism - to analyse the Acts and gauge the historiographical aims of their author. Marguerat examines the construction of the narrative, the framing of the plot and the characterization, and places his evaluation firmly in the framework of ancient historiography, where history reflects tradition and not documentation. This is a fresh and original approach to the classic themes of Lucan theology: Christianity between Jerusalem and Rome, the image of God, the work of the Spirit, the unity of Luke and the Acts.

Activity of ancestral restriction factors against ancient retroviruses

Analysis of TRIM5α and APOBEC3G genes suggests that these two restriction factors underwent strong positive selection throughout primate evolution. This pressure was possibly imposed by ancient exogenous retroviruses, of which endogenous retroviruses are remnants. Our study aims to assess in vitro the activity of these factors against ancient retroviruses by reconstructing their ancestral gag sequences, as well as the ancestral TRIM5α and APOBEC3G for primates. Based on evolutionary genomics approach, we reconstructed ancestors of the two largest families of human endogenous retroviruses (HERV), namely HERV-K and HERV-H, as well as primate ancestral TRIM5α and APOBEC3G variants. The oldest TRIM5α sequence was the catarhinne TRIM5α, common ancestor of Old World monkeys and hominoids, dated from 25 million years ago (mya). From the oldest, to the youngest, ancestral TRIM5α variants showed less restriction of HIV-1 in vitro [1]. Likewise three ancestral APOBEC3Gs sequences common to hominoids (18 mya), Old World monkeys, and catarhinnes (25 mya) were reconstructed. All ancestral APOBEC3G variants inhibited efficiently HIV-1Δvif in vitro, compared to modern APOBEC3Gs. The ability of Vif proteins (HIV-1, HIV-2, SIVmac and SIVagm) to counteract their activity tallied with the residue 128 on ancestral APOBEC3Gs. Moreover we are attempting to reconstruct older ancestral sequences of both restriction factors by using prosimian orthologue sequences. An infectious onemillion- years-old HERV-KCON previously reconstituted was shown to be resistant to modern TRIM5α and APOBEC3G [2]. Our ancestral TRIM5α and APOBEC3G variants were inactive against HERV-KCON. Besides we reconstructed chimeric HERV-K bearing ancestral capsids (up to 7 mya) that resulted in infectious viruses resistant to modern and ancestral TRIM5α. Likewise HERV-K viruses bearing ancestral nucleocapsids will be tested for ancestral and modern APOBEC3G restriction. In silico reconstruction and structural modeling of ancestral HERV-H capsids resulted in structures homologous to that of the gammaretrovirus MLV. Thus we are attempting to construct chimeric MLV virus bearing HERV-H ancestral capsids. These chimeric ancestral HERVs will be tested for infectivity and restriction by ancestral TRIM5α. Similarly chimeric MLV viruses bearing ancestral HERV-H nucleocapsids will be reconstructed and tested for APOBEC3G restriction.