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Global Rise (global + rise)
Selected AbstractsSedimentary and faunal events revealed by a revised correlation of post-glacial Hirnantian (Late Ordovician) strata in the Welsh Basin, UKGEOLOGICAL JOURNAL, Issue 3 2009Jeremy R. Davies Abstract The discovery of a previously unrecognized unconformity and of new faunas in the type Llandovery area underpins a revised correlation of Hirnantian strata in mid Wales. This has revealed the sedimentary and faunal events which affected the Lower Palaeozoic Welsh Basin during the global rise in sea level that followed the end-Ordovician glacial maximum and has allowed their interpretation in the context of local and global influences. In peri-basinal shelfal settings the onset of post-glacial deepening is recorded by an unfossiliferous, transgressive shoreface sequence (Cwm Clyd Sandstone and Garth House formations) which rests unconformably on Rawtheyan rocks, deformed during an episode of pre-Hirnantian tectonism. In the deep water facies of the basin centre, this same sequence boundary is now recognized as the contact between fine-grained, re-sedimented mudstones and an underlying regressive sequence of turbidite sandstones and conglomerates; it is at a level lower than previously cited and calls into question the established lithostratigraphy. In younger Hirnantian strata, graptolites associated with the newly recognized Ystradwalter Member (Chwefri Formation) demonstrate that this distal shelf unit correlates with the persculptus graptolite-bearing Mottled Mudstone Member of the basinal succession. Together these members record an important macrofaunal recolonization of the Welsh Basin and mark a key event in the post-glacial transgression. Further deepening saw the establishment of a stratified water column and the imposition of anoxic bottom water conditions across the basin floor. These post-glacial Hirnantian events are consistent with the re-establishment of connections between a silled Welsh Basin and the open Iapetus Ocean. However, a comparison with other areas suggests that each event records a separate deepening episode within a pulsed glacio-eustatic transgression, while also reflecting changes in post-glacial climate and patterns of oceanic circulation and associated biotic flux. British Geological Survey © NERC 2009. All rights reserved. [source] Will photosynthesis of maize (Zea mays) in the US Corn Belt increase in future [CO2] rich atmospheres?GLOBAL CHANGE BIOLOGY, Issue 6 2004An analysis of diurnal courses of CO2 uptake under free-air concentration enrichment (FACE) Abstract The C4 grass Zea mays (maize or corn) is the third most important food crop globally in terms of production and demand is predicted to increase 45% from 1997 to 2020. However, the effects of rising [CO2] upon C4 plants, and Z. mays specifically, are not sufficiently understood to allow accurate predictions of future crop production. A rainfed, field experiment utilizing free-air concentration enrichment (FACE) technology in the primary area of global corn production (US Corn Belt) was undertaken to determine the effects of elevated [CO2] on corn. FACE technology allows experimental treatments to be imposed upon a complete soil,plant,atmosphere continuum with none of the effects of experimental enclosures on plant microclimate. Crop performance was compared at ambient [CO2] (354 , mol mol,1) and the elevated [CO2] (549 ,mol mol,1) predicted for 2050. Previous laboratory studies suggest that under favorable growing conditions C4 photosynthesis is not typically enhanced by elevated [CO2]. However, stomatal conductance and transpiration are decreased, which can indirectly increase photosynthesis in dry climates. Given the deep soils and relatively high rainfall of the US Corn Belt, it was predicted that photosynthesis would not be enhanced by elevated [CO2]. The diurnal course of gas exchange of upper canopy leaves was measured in situ across the growing season of 2002. Contrary to the prediction, growth at elevated [CO2] significantly increased leaf photosynthetic CO2 uptake rate (A) by up to 41%, and 10% on average. Greater A was associated with greater intercellular [CO2], lower stomatal conductance and lower transpiration. Summer rainfall during 2002 was very close to the 50-year average for this site, indicating that the year was not atypical or a drought year. The results call for a reassessment of the established view that C4 photosynthesis is insensitive to elevated [CO2] under favorable growing conditions and that the production potential of corn in the US Corn Belt will not be affected by the global rise in [CO2]. [source] Critical Therapeutics: Cultural Politics and Clinical Reality in Two Eating Disorder Treatment CentersMEDICAL ANTHROPOLOGY QUARTERLY, Issue 4 2007Rebecca J. Lester Recent studies suggest that eating disorders are increasing in Mexico and that this seems to correspond with Mexico's push to modernization. In this respect, Mexico exemplifies the acculturation hypothesis of eating disorders, namely, that anorexia and bulimia are culture-bound syndromes tied to postindustrial capitalist development and neoliberalist values, and that their appearance elsewhere is indicative of acculturation to those values. Available evidence for this claim, however, is often problematic. On the basis of five years of comparative fieldwork in eating disorder clinics in Mexico City and a small Midwestern city in the United States, I reframe this as an ethnographic question by examining how specific clinical practices at each site entangle global diagnostic categories with local social realities in ways that problematize existing epistemologies about culture and illness. In this regard, debates about acculturation and the global rise of eating disorders foreground issues of central epistemological and practical importance to contemporary medical anthropology more generally. [source] LAVICHÈ: HAITI'S VULNERABILITY TO THE GLOBAL FOOD CRISISANNALS OF ANTHROPOLOGICAL PRACTICE, Issue 1 2009John Mazzeo In April 2008, the global rise in food prices reached a breaking point in Haiti where a series of food riots swept across the country. The majority of Haitians depend on the marketplace for food, especially imported rice. The dependence on the marketplace for food and the rise in prices has caused households to reduce purchases leading to growing hunger especially among the rural poor. Haiti's vulnerability to the food crisis is not a problem of supply; it's because of the high cost of living, lavichè in Haitian Creole. This article poses the question, why is Haiti, a country rooted in peasant agricultural production, vulnerable to the rise in global food prices. I propose that answers to the current crisis come from an understanding of rural livelihoods, strategies for accessing food, and global food policies. Rural households are not subsistence producers. Ironically, they have suffered most from the rise in prices because of their dependence on the marketplace. Changing consumption patterns relying on imported rather than domestic staples have increased vulnerability to rising prices. Additionally, economic policies surrounding the import and marketing of food have further increased Haiti's dependence on imports. Understanding the trends leading to Haiti's current food crisis will help to inform policies and programs aimed at providing temporary food assistance and hopefully lead to more effective development programs. This article is based on research conducted in rural Haiti during the summer of 2008, part of which was for World Vision International as it prepared to mitigate the crisis through food assistance programs. [source] Strategies for early prevention of asthmaCLINICAL & EXPERIMENTAL ALLERGY REVIEWS, Issue 2004Fernando Maria De Benedictis Summary Asthma is the most commonly diagnosed chronic disease in childhood. Pathogenesis of the disease has received much attention lately as the last few decades have seen such a global rise in prevalence. There is hope to reverse this trend in prevalence by developing new preventive strategies. Here, we summarize the recent evidence for the role of early life events such as prenatal factors, infections, pollution, allergen exposure, nutrition, and discuss the implications for future strategies for asthma prevention. [source] | ||||||||||