Recent Advances in Modeling Stellar Interiors

Advances in stellar interior modeling are being driven by new data from large-scale surveys and high-precision photometric and spectroscopic observations. Here we focus on single stars in normal evolutionary phases; we will not discuss the many advances in modeling star formation, interacting binaries, supernovae, or neutron stars. We review briefly: 1) updates to input physics of stellar models; 2) progress in two and three-dimensional evolution and hydrodynamic models; 3) insights from oscillation data used to infer stellar interior structure and validate model predictions (asteroseismology). We close by highlighting a few outstanding problems, e.g., the driving mechanisms for hybrid gamma Dor/delta Sct star pulsations, the cause of giant eruptions seen in luminous blue variables such as eta Car and P Cyg, and the solar abundance problem.Comment: Proceedings for invited talk at conference High Energy Density Laboratory Astrophysics 2010, Caltech, March 2010, submitted for special issue of Astrophysics and Space Science; 7 pages; 5 figure

Detection and Molecular Characterization of 9000-Year-Old Mycobacterium tuberculosis from a Neolithic Settlement in the Eastern Mediterranean

Background: Mycobacterium tuberculosis is the principal etiologic agent of human tuberculosis. It has no environmental reservoir and is believed to have co-evolved with its host over millennia. This is supported by skeletal evidence of the disease in early humans, and inferred from M. tuberculosis genomic analysis. Direct examination of ancient human remains for M. tuberculosis biomarkers should aid our understanding of the nature of prehistoric tuberculosis and the host/pathogen relationship.Methodology/Principal Findings: We used conventional PCR to examine bone samples with typical tuberculosis lesions from a woman and infant, who were buried together in the now submerged site of Atlit-Yam in the Eastern Mediterranean, dating from 9250-8160 years ago. Rigorous precautions were taken to prevent contamination, and independent centers were used to confirm authenticity of findings. DNA from five M. tuberculosis genetic loci was detected and had characteristics consistent with extant genetic lineages. High performance liquid chromatography was used as an independent method of verification and it directly detected mycolic acid lipid biomarkers, specific for the M. tuberculosis complex.Conclusions/Significance: Human tuberculosis was confirmed by morphological and molecular methods in a population living in one of the first villages with evidence of agriculture and animal domestication. The widespread use of animals was not a source of infection but may have supported a denser human population that facilitated transmission of the tubercle bacillus. The similarity of the M. tuberculosis genetic signature with those of today gives support to the theory of a long-term co-existence of host and pathogen

Detecting and quantifying stress granules in tissues of multicellular organisms with the Obj.MPP analysis tool

International audienceStress Granules (SGs) are macromolecular assemblies induced by stress and composed of proteins and mRNAs stalled in translation initiation. SGs play an important role in the response to stress and in the modulation of signaling pathways. Furthermore, these structures are related to the pathological ribonucleoprotein (RNP) aggregates found in neurodegenerative disease contexts, highlighting the need to understand how they are formed and recycled in normal and pathological contexts. Although genetically tractable multicellular organisms have been key in identifying modifiers of RNP aggregate toxicity, in vivo analysis of SG properties and regulation has lagged behind, largely due to the difficulty of detecting SG from images of intact tissues. Here, we describe the object detector software Obj.MPP and show how it overcomes the limits of classical object analyzers to extract the properties of SGs from wide-field and confocal images of respectively C. elegans and Drosophila tissues. We demonstrate that Obj.MPP enables the identification of genes modulating the assembly of endogenous and pathological SGs, and thus that it will be useful in the context of future genetic screens and in vivo studies. This article is protected by copyright. All rights reserved

New insights on Final Epigravettian funerary behaviour at Arene Candide Cave (Western Liguria, Italy) from osteological and spatial analysis of secondary bone deposits

We gained new insights on Epigravettian funerary behavior at the Arene Candide cave through the osteological and spatial analysis of the burials and human bone accumulations found in the cave during past excavations. Archaeothanathological information on the human skeletal remains was recovered from diaries, field pictures and notes, and data from recent excavations was integrated. The secondary deposits have traditionally been interpreted as older burials that were disturbed to make space for new inhumations. Our results suggest that those disturbances were not casual: older burials were intentionally displaced to bury younger inhumations. Subsequently, some skeletal elements, especially crania, were arranged around the new burial; these were often placed within stone niches. Based on the composition of some clusters, which contain the bones of two individuals displaced together, it is possible that a double burial composed of two adults was originally present at the site. This would be a burial type that had not been recognized at Arene Candide until now. Strikingly, this potential double burial contained an individual showing pathological bowing of the limbs, a finding which is not infrequent in skeletons from Gravettian and Epigravettian multiple burials. In addition, the crania and other skeletal elements derived from this burial were intentionally placed around a new inhumation, whose skeleton possibly shows a milder form of the same disease (possibly hereditary rickets). This and other observations suggest that the five individuals belonging to the second phase of this “cemetery” (AMS dates spanning 12,030 – 11,180 cal BP) might have been buried over a relatively brief time span. Our study demonstrated similar behaviors in the first phase of mortuary use of the cave (12,820 – 12,420 cal BP), indicating a remarkable persistence in Final Epigravettian funerary models despite their archaeologically apparent rarity and intermittent nature