Hepatitis B virus (HBV) is a major cause of human hepatitis. There is considerable uncertainty about the timescale of its evolution and its association with humans. Here we present 12 full or partial ...ancient HBV genomes that are between approximately 0.8 and 4.5 thousand years old. The ancient sequences group either within or in a sister relationship with extant human or other ape HBV clades. Generally, the genome properties follow those of modern HBV. The root of the HBV tree is projected to between 8.6 and 20.9 thousand years ago, and we estimate a substitution rate of 8.04 × 10
-1.51 × 10
nucleotide substitutions per site per year. In several cases, the geographical locations of the ancient genotypes do not match present-day distributions. Genotypes that today are typical of Africa and Asia, and a subgenotype from India, are shown to have an early Eurasian presence. The geographical and temporal patterns that we observe in ancient and modern HBV genotypes are compatible with well-documented human migrations during the Bronze and Iron Ages
. We provide evidence for the creation of HBV genotype A via recombination, and for a long-term association of modern HBV genotypes with humans, including the discovery of a human genotype that is now extinct. These data expose a complexity of HBV evolution that is not evident when considering modern sequences alone.
In Fig. 2 of this Letter, the 'E' and 'G' clade labels were inadvertently reversed, and in Table 2 the genotype of DA27 was 'D1' instead of 'D5'. These have been corrected online.
Direct and accurate radiocarbon dating of lipid residues preserved in ceramics is a recently established method that allows direct dating of specific food products and their inception in human ...subsistence strategies. The method targets individual fatty acids originating from animal fats such as ruminant dairy, ruminant adipose, non-ruminant adipose and aquatic fats. Horse lipid residues found in Central Asian pottery vessels are also directly dateable using this new method. Here we present the identification of equine lipid residues preserved in two pottery assemblages from the Neolithic and Eneolithic in Kazakhstan and their direct
14
C dating. The site of Botai, previously radiocarbon-dated to the 4th millennium BC, was used as a reference to evaluate the dates obtained directly on horse lipids. The direct dating of equine products extracted from Botai potsherds are shown to be compatible with previous
14
C dates at the site. The site of Bestamak, lacking previous
14
C measurements, had been relatively dated to the Neolithic based on pottery typologies. The direct dating of equine residues made it possible to anchor the pottery assemblage of Bestamak in the 6th millennium BC confirming their Neolithic attribution. These findings demonstrate the potential for dating horse products through a compound-specific approach, while highlighting challenges in
14
C dating individual fatty acids from lipid extracts in which their abundances differ substantially.
In such a highly competitive and safety-oriented industry as aviation, an important task in the after-sales service of civil aviation is to provide operators with operational information on its ...maintenance. In practice, the solution to this problem is the use of interactive electronic technical manuals and services that provide access to such documentation. This paper presents an overview of the promising areas of interactive electronic technical manuals development in terms of the use of 3D visualization of technical data, as well as an overview of the relevant services. The article considers the features of the application of 3D visualization in the after-sales services of Airbus, Boeing, Embraer, GE Aviation and Rolls-Royce. The features of the development and results of the application of 3D visualization by the domestic aircraft developer - JSC Irkut Corporation - are considered in two directions: for procedures in the Aircraft Maintenance Manual, made in the interactive electronic technical manual format, and for the after-sales information service, designed to record information about the technical condition of the aircraft structure. The use of 3D visualization in the interactive electronic technical manual of JSC Irkut Corporation makes it possible to increase the efficiency of performing maintenance procedures and improve the quality of the manual as a whole at the stage of its development. "Aircraft structure technical condition reporting system" developed on the interactive electronic technical manual database allows you to directly interact with the Structural Repair Manual, link information about damages and repairs performed to specific structural elements of the aircraft on a 3D model, carry out an operational exchange of this information by all interested parties, as well as create requests to the aircraft developer for damages not described in the manual.
Porous silica-based monoliths obtained by spinodal phase decomposition of water-tetraethoxysilane mixtures in the presence of polyethylene oxide were tested for pre-concentration of dimethyl ...methylphosphonate (DMMP) to increase the sensitivity of its detection by semiconductor gas sensors. The best performance in terms of complete adsorption/fast thermodesorption was shown by the sample with a surface area of 280 m2/g. The monoliths with lower surface area were not so effective in DMMP adsorption. while for the samples with higher surface area. the decrease of the sensor signal was observed due to impeded DMMP desorption.
PDF
