Tuberculosis in evolution

International audienc

Nanostructure and mechanics of mummified type I collagen from the 5300-year-old Tyrolean Iceman

Skin protects the body from pathogens and degradation. Mummified skin in particular is extremely resistant to decomposition. External influences or the action of micro-organisms, however, can degrade the connective tissue and lay the subjacent tissue open. To determine the degree of tissue preservation in mummified human skin and, in particular, the reason for its durability, we investigated the structural integrity of its main protein, type I collagen. We extracted samples from the Neolithic glacier mummy known as ‘the Iceman’. Atomic force microscopy (AFM) revealed collagen fibrils that had characteristic banding patterns of 69 ± 5 nm periodicity. Both the microstructure and the ultrastructure of dermal collagen bundles and fibrils were largely unaltered and extremely well preserved by the natural conservation process. Raman spectra of the ancient collagen indicated that there were no significant modifications in the molecular structure. However, AFM nanoindentation measurements showed slight changes in the mechanical behaviour of the fibrils. Young's modulus of single mummified fibrils was 4.1 ± 1.1 GPa, whereas the elasticity of recent collagen averages 3.2 ± 1.0 GPa. The excellent preservation of the collagen indicates that dehydration owing to freeze-drying of the collagen is the main process in mummification and that the influence of the degradation processes can be addressed, even after 5300 years

The Palermo Capuchin Catacombs Project: a multidisciplinary approach to the study of a modern Mummy Collection (ca 1600-1900)

In this paper we present a multidisciplinary project for the study of the present conditions, history, bioanthropological features and conservation status of a large collection of modern human mummies, kept in the Capuchin Catacombs of Palermo (Sicily, Italy). Due to the large amount of spontaneously and anthropogenically mummified human bodies, and to an abundant presence of associated artefacts, this collection provides a unique opportunity to carry out a large multidisciplinary survey useful for a thorough biocultural understanding of these remains, a conservation plan, and testing of new restoration protocols

TARGET: toward a solution for the readout electronics of the Cherenkov Telescope Array

TARGET is an application specific integrated circuit (ASIC) designed to read out signals recorded by the photosensors in cameras of very-high-energy gamma-ray telescopes exploiting the imaging of Cherenkov radiation from atmospheric showers. TARGET capabilities include sampling at a high rate (typically 1 GSample/s), digitization, and triggering on the sum of four adjacent pixels. The small size, large number of channels read out per ASIC (16), low cost per channel, and deep buffer for trigger latency (~16 $\mu$s at 1 GSample/s) make TARGET ideally suited for the readout in systems with a large number of telescopes instrumented with compact photosensors like multi-anode or silicon photomultipliers combined with dual-mirror optics. The possible advantages of such systems are better sensitivity, a larger field of view, and improved angular resolution. The two latest generations of TARGET ASICs, TARGET 5 and TARGET 7, are soon to be used for the first time in two prototypes of small-sized and medium-sized dual-mirror telescopes proposed in the framework of the Cherenkov Telescope Array (CTA) project. In this contribution we report on the performance of the TARGET ASICs and discuss future developments.Comment: 8 pages, 3 figures. In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions at arXiv:1508.0589

“Celts” up and down the Alps. Insights on mobility patterns in the pre‐Roman /Celtic population from Verona ( NE Italy, 3rd–1st c. BCE ): A multi‐isotopic approach

OBJECTIVES: The Late Iron Age in continental Europe featured complex demographic processes including, among others, the establishment of transalpine “Celtic” communities on the Italian peninsula between the 4th and 1st centuries BCE. To date, only few data are available about mobility and migration in these populations. Here we explore these topics among the Cenomani of Seminario Vescovile (SV‐Verona, Italy, 3rd–1st c. BCE) through a multi‐isotopic approach and test the possible associations with sex, age and funerary treatment. MATERIALS AND METHODS: We analyzed isotopic ratios of oxygen (δ (18)O) and carbon (δ (13)C) from bone phosphate and collagen, respectively, of 49 individuals (23 males, 17 females, and 9 nonadults). In addition, we explored possible intraindividual lifetime changes by comparing collagen δ (13)C from bone and dentine of 26 individuals. We assessed nonlocality based on individual deviation of isotopic values from the population mean plus three times the median absolute deviation from the median (±3MAD). We then checked for isotopic differences between sexes and type of funerary treatment using Mann–Whitney tests. RESULTS: One individual shows isotopic values consistent with a nonlocal origin. Five more individuals may have originated from a different locality. No statistical differences separate sexes and types of funerary treatment. DISCUSSION: Results suggest a local origin of most of the individuals of SV with the few exceptions pointing especially to an Alpine origin. The low frequency of nonlocals at SV suggest a reduced mobility in this population, or the preeminence of short distance movements undetected by our analyses

"Celts" up and down the Alps. A multi-isotopic exploration of mobility among the pre-Roman population of Verona (NE Italy, 3rd -1st c. BCE)

During the Late Iron Age (4th-1st centuries BCE) Europe was interested by intense migratory processes across the Alps. In this period, several "Celtic" populations settled in the Italian peninsula. So far, only scarce data are available about mobility in these communities. In this work, we explore mobility patterns among the Cenomani population of Seminario Vescovile (SV-Verona, Italy, 3rd-1st c. BCE) through a multi-isotopic perspective and test the possible correlation between mobility, sex, age and funerary treatment. We analyzed isotopic ratios of oxygen (δ18O) and carbon (δ13C) from bone phosphate and collagen, respectively, of 49 individuals (23 males, 17 females and 9 nonadults). We also compared collagen δ13C from bone and dentine of 26 individuals. We assessed nonlocality based on individual deviation of isotopic values from the population mean plus three times the median absolute deviation from the median (±3MAD). We then checked for isotopic differences between sexes and type of funerary treatment using Mann-Whitney tests. A nonlocal origin can be proposed for one individual and cautiously suggested for five more individuals. No statistical difference separates sex nor funerary treatment based on isotopic values. Results highlight a local origin of most of the individuals of SV with few individuals that may point to an Alpine origin. The degree of mobility at SV is lower compared with other contemporaneous sites of Europe, a result that can be attributed to chronological and social factors but also to methodological differences with previous studies

FloorNet: Deployment and Evaluation of a Multihop Wireless 802.11 Testbed

A lot of attention has been given to multihop wireless networks lately, but further research—in particular, through experimentation—is needed. This attention has motivated an increase in the number of 802.11-based deployments, both indoor and outdoor. These testbeds, which require a significant amount of resources during both deployment and maintenance, are used to run measurements in order to analyze and understand the limitation and differences between analytical or simulation-based figures and the results from real-life experimentation. This paper makes two major contributions: (i) first, we describe a novel wireless multihop testbed, which we name FloorNet, that is deployed and operated under the false floor of a lab in our Computer Science building. This false floor provides a strong physical protection that prevents disconnections or misplacements, as well as radio shielding (to some extent) thanks to the false floor panels—this later feature is assessed through experimentation; (ii) second, by running exhaustive and controlled experiments we are able to analyze the performance limits of commercial off-theshelf hardware, as well as to derive practical design criteria for the deployment and configuration of mesh networks. These results both provide valuable insights of wireless multihop performance and prove that FloorNet constitutes a valuable asset to research on wireless mesh networks.European Community's Seventh Framework ProgramPublicad

Metagenomic analysis of ancient dental calculus reveals unexplored diversity of oral archaeal Methanobrevibacter

Background Dental calculus (mineralised dental plaque) preserves many types of microfossils and biomolecules, including microbial and host DNA, and ancient calculus are thus an important source of information regarding our ancestral human oral microbiome. In this study, we taxonomically characterised the dental calculus microbiome from 20 ancient human skeletal remains originating from Trentino-South Tyrol, Italy, dating from the Neolithic (6000–3500 BCE) to the Early Middle Ages (400–1000 CE). Results We found a high abundance of the archaeal genus Methanobrevibacter in the calculus. However, only a fraction of the sequences showed high similarity to Methanobrevibacter oralis, the only described Methanobrevibacter species in the human oral microbiome so far. To further investigate the diversity of this genus, we used de novo metagenome assembly to reconstruct 11 Methanobrevibacter genomes from the ancient calculus samples. Besides the presence of M. oralis in one of the samples, our phylogenetic analysis revealed two hitherto uncharacterised and unnamed oral Methanobrevibacter species that are prevalent in ancient calculus samples sampled from a broad range of geographical locations and time periods. Conclusions We have shown the potential of using de novo metagenomic assembly on ancient samples to explore microbial diversity and evolution. Our study suggests that there has been a possible shift in the human oral microbiome member Methanobrevibacter over the last millennia