The concentration of radiocarbon (14C) differs between ocean and atmosphere. Radiocarbon determinations from samples which obtained their 14C in the marine environment therefore need a marine-specific calibration curve and cannot be calibrated directly against the atmospheric-based IntCal20 curve. This paper presents Marine20, an update to the internationally agreed marine radiocarbon age calibration curve that provides a non-polar global-average marine record of radiocarbon from 0–55 cal kBP and serves as a baseline for regional oceanic variation. Marine20 is intended for calibration of marine radiocarbon samples from non-polar regions; it is not suitable for calibration in polar regions where variability in sea ice extent, ocean upwelling and air-sea gas exchange may have caused larger changes to concentrations of marine radiocarbon. The Marine20 curve is based upon 500 simulations with an ocean/atmosphere/biosphere box-model of the global carbon cycle that has been forced by posterior realizations of our Northern Hemispheric atmospheric IntCal20 14C curve and reconstructed changes in CO2 obtained from ice core data. These forcings enable us to incorporate carbon cycle dynamics and temporal changes in the atmospheric 14C level. The box-model simulations of the global-average marine radiocarbon reservoir age are similar to those of a more complex three-dimensional ocean general circulation model. However, simplicity and speed of the box model allow us to use a Monte Carlo approach to rigorously propagate the uncertainty in both the historic concentration of atmospheric 14C and other key parameters of the carbon cycle through to our final Marine20 calibration curve. This robust propagation of uncertainty is fundamental to providing reliable precision for the radiocarbon age calibration of marine based samples. We make a first step towards deconvolving the contributions of different processes to the total uncertainty; discuss the main differences of Marine20 from the previous age calibration curve Marine13; and identify the limitations of our approach together with key areas for further work. The updated values for ΔR, the regional marine radiocarbon reservoir age corrections required to calibrate against Marine20, can be found at the data base http://calib.org/marine/.

Our repertoire of concepts and theories concerning peasantries has been built up through contributions from scholars working in many parts of the world. Latin Americanists and India-wallahs, in particular, have played a major role in the development of models, but we have also heard from specialists in Indonesia, Japan, Europe, the Mediterranean world, and even Africa. But where is China in all this ? Why are students of the world's largest peasantry silent? In part, it is because we are so few and too preoccupied with our own peasants to have time for anybody else's. More to the point, however, the whole body of inherited anthropological wisdom concerning peasantries seems somehow alien and irrelevant to students of Chinese society.

110 isolates of Beauveria (104 B. bassiana, 5 Beauveria spp., 1 B. brongniartii) were obtained from Sunn Pests (Eurygaster and Aelia species), litter, and other insect samples at overwintering sites in seven countries in the Middle East and West Asia. DNA was extracted from these isolates, and four techniques were used to characterize and to investigate genetic diversity at the molecular level: ITS-RFLP, ITS sequencing, ISSR-PCR, and AFLP. The ITS-RFLP and ITS sequences did not detect significant genetic variation among the isolates. However, both ISSR-PCR and AFLP analyses gave indications of intraspecific groupings correlated with geographical origin and relative genetic diversity among some isolates, but no obvious association with Sunn Pest hosts. There was no obvious genotypic grouping of B. bassiana isolates from E. integriceps, perhaps suggesting the overwintering populations were infected by generalist native isolates rather than by host-specific ones that might be more suitable for biocontrol purposes.

We present the results of a high-resolution Chandra X-ray image of the Wolf-Rayet binary system WR 147, which consists of a WN8 star and an early-type companion located 0″.6 to its north. The image provides the first direct evidence for spatially extended X-ray emission in an early-type binary system, and shows that the emission peaks north of the WN8 star and close to the position of the radio bow shock. Simulated X-ray images of the wind-wind collision have a fwhm consistent with the data, but cannot account for the full spatial extension, unless emission from the stars is also included.

Key features of reproductive behavior in China vary systematically through space and time. In this article we present an analysis of fertility change in regional space, using a 1% household sample from China’s 1990 population census. Elsewhere,we use the same data to analyze reproductive strategizing, but here we pursue the big picture with a straightforward analysis that takes reported births as an uncomplicated indicator of fertility.The article has three objectives: first, to introduce a novel, multilevel spatial model of regional structure constructed using a geographic information system (GIS); second, to demonstrate the potential for longitudinal data derived from onetime censuses to contribute to historical demography in conjunction with regional analysis; and third, to document the manner in which China’s fertility transition has unfolded in regional space.

As more health authorities close large psychiatric hospitals the provision of small local facilities in which former residents of such hospitals are housed is increasing. Such houses tend to share many common characteristics dictated both by practical necessity and by deliberate policy – they tend to be large Victorian houses chosen because they have a larger number of bedrooms and they tend to be run in a much less formal manner than hospital wards (Goldberg, 1985).

Rural markets and peasant marketing did not fare well during the Maoist era, which extended from well before the consolidation of communist power in China to the triumphal return of Deng Xiaoping as the central political figure in 1977. Maoist radicals, who in broad perspective may be said to have held the political initiative throughout the era, can be fairly characterized as having an anti-market mentality. While this set of attitudes derives in part from Marxism, it is also rooted in the ideological preconceptions of late-imperial Confucian bureaucrats. The Maoist elite in the People's Republic and the traditional bureaucratic elite of the late empire were equally unhappy with market exchange, and both showed a preference for redistribution.

The developmental trajectories of North China and the Southeast Coast during the middle and late imperial periods are surveyed to illustrate the recurrence of regional macrocycles of development and decline and to show that such cycles may be unsynchronized as between regions. These cases provide a basis for arguing that economic macrocycles are a systemic property—not of provinces or of the empire as a whole but of regional economies viewed as internally differentiated and interdependent systems of human interaction. An exploration of the relation between regional developmental cycles and the Chinese dynastic cycle concludes that the latter was mediated by the former. It is suggested that regional developmental cycles are cycles not only of economic prosperity and depression but also of population growth and decline, of social development and devolution, and of peace and disorder. China's historical structure, then, is seen as an internested hierarchy of local and regional histories whose scope in each case is grounded in the spatial patterning of human interaction, and whose critical temporal structures are successive cyclical episodes. The uses of such an historiographic model are briefly explored.

Cooper and platinum films were deposited by evaporation and sputtering techniques onto prepared substrates of alumina, sapphire (cut along an a or c axis) and yttria stabilized zirconia. The films are then bombarded with ions of H, He, Ne and Kr at energies within and outside the ion beam mixing regime. Ion beam induced modification in adhesion and its thermal stability were measured by three techniques - a scratch test, a pull test and a peel test. Adhesive energies of these solid-solid systems were determined by contact angle measurements using scanning electron microscopy. The resistance of the films to chemical attack is modified by ion bombardment and will be shown to correlate with adhesion alterations.

Foodstuffs comprise the largest single category of urban supply in China, and food accounts for over half the expenditures of the average urban household. Grain and other starchy staples constitute the major component of urban food supply, followed by vegetables and meat. In terms of weight or volume, far more vegetables than meat are consumed by city dwellers, though in terms of value meat may have the edge. The focus here is on vegetables, in particular the ecology of production, the organization of procurement and the structure of the marketing system. The logistics of feeding urban populations is critical in any complex society, indicative inter alia of priorities and procedural preferences in the social system. To examine the organization of urban vegetable supply therefore offers clues to these social priorities as well as to prevailing levels of organizational sophistication.