Survey of painting practice for protection of offshore structures

SIGLELD:f84/0216 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

An integrative approach to estimating productivity in past societies using Seshat:Global History Databank

This article reports the results of a collaborative effort to estimate agricultural productivities in past societies using Seshat: Global History Databank. We focus on 30 Natural Geographic Areas (NGAs) distributed over 10 major world regions (Europe, Africa, Southwest Asia, South Asia, Southeast Asia, East Asia, Central Eurasia, North America, South America, and Oceania). The conceptual framework that we use to obtain these estimates combines the influences of the production technologies (and how they change with time), climate change, and effects of artificial selection into a Relative Yield Coefficient, indicating how agricultural productivity changed over time in each NGA between the Neolithic and the 20th century. We then use estimates of historical yield in each NGA to translate the Relative Yield Coefficient into an Estimated Yield (tonnes per hectare per year) trajectory. We tested the proposed methodology in two ways. For eight NGAs, in which we had more than one historical yield estimate, we used the earliest estimate to anchor the trajectory and compared the ensuing trajectory to the remaining estimates. We also compared the end points of the estimated NGA trajectories to the earliest (the 1960s decade) FAO data on crop productivities in the modern countries encompassing Seshat NGAs. We discuss the benefits of this methodology over previous efforts to estimate agricultural productivities in world history

Genomic analysis of diversity, population structure, virulence, and antimicrobial resistance in Klebsiella pneumoniae, an urgent threat to public health

Klebsiella pneumoniae is nowrecognized as an urgent threat to human health because of the emergence of multidrug-resistant strains associated with hospital outbreaks and hypervirulent strains associated with severe community-acquired infections. K. pneumoniae is ubiquitous in the environment and can colonize and infect both plants and animals. However, little is known about the population structure of K. pneumoniae, so it is difficult to recognize or understand the emergence of clinically important clones within this highly genetically diverse species. Here we present a detailed genomic framework for K. pneumoniae based on whole-genome sequencing of more than 300 human and animal isolates spanning four continents. Our data provide genomewide support for the splitting of K. pneumoniae into three distinct species, KpI (K. pneumoniae), KpII (K. quasipneumoniae), and KpIII (K. variicola). Further, for K. pneumoniae (KpI), the entity most frequently associated with human infection, we show the existence of >150 deeply branching lineages including numerousmultidrug-resistant or hypervirulent clones.We show K. pneumoniae has a large accessory genome approaching 30,000 protein-coding genes, including a number of virulence functions that are significantly associated with invasive community-acquired disease in humans. In our dataset, antimicrobial resistance genes were common among human carriage isolates and hospital-acquired infections, which generally lacked the genes associated with invasive disease. The convergence of virulence and resistance genes potentially could lead to the emergence of untreatable invasive K. pneumoniae infections; our data provide the whole-genome framework against which to track the emergence of such threats