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311.
Elizabeth Kenworthy Teather 《Singapore journal of tropical geography》2001,22(2):156-172
This paper focuses on Hong Kong's Gravesweeping Festivals, Qingming and Chongyang. The practices carried out in urban cemeteries at these Festivals are over two thousand years old, and represent “time out” from modern “clock time”. They are examined in the context of Giddens' (1985) reworking of Hägerstrand's time‐space geography, and of Douglas' (1966) discussion of pollution. It is suggested that the cemeteries are regarded as dangerous places because they represent liminal spaces. Giddens' dimension of span enables a distinction to be made between, on the one hand, the long‐established cultural significance of the grave, and, on the other, the recentness of the urban cemetery. The dimension of form(redefined from Giddens' original concept), applied to some details of cemetery landscapes, reveals the “worlds apart” of the non‐material worlds of the spirits and of fengshui. By considering the Festivals in the light of Giddens' dimension, character, it emerges that the Gravesweeping Festivals are, as they have been for centuries, firmly embedded in Hong Kong's social system, where routines of ancestor veneration continue to renew and strengthen the family bonds that are at the heart of Confucian values. Furthermore, their continued observation may well represent practices that are of deep ontological significance to the predominantly immigrant community of Hong Kong. 相似文献
312.
313.
Elizabeth Casman Baruch Fischhoff Mitchell Small Hadi Dowlatabadi Joan Rose M. Granger Morgan 《Climatic change》2001,50(1-2):219-249
The effects of climate change on drinking-waterborne cryptosporidiosis transmission in the United States are analyzed using an influence diagram representation of epidemic development. Results from a systematic qualitative analysis indicate that climate change will have little effect on cryptosporidiosis incidence if the United States continues to be wealthy and maintains its commitment to public health. The major impact will, instead, be the additional costs of adapting to new climate regimes in order to avoid drinking-waterborne disease risk. These costs, for the most part, will be from improved monitoring and treatment of drinking water. The consequences of disaster scenarios are also considered. These, too, suggest that climate change per se will be a poor predictor of waterborne cryptosporidiosis in countries with high standards of living. Rather, the risk of epidemics will depend on the interplay between population, public health investment, infrastructure maintenance, emergency planning/response capabilities, water-treatment technologies, drinking-water regulations, and climate. 相似文献
314.
Over the past decade, sinking particulate organic matter (POM) samples from depth profiles in the equatorial Pacific have been analyzed by multiple techniques to evaluate the organic matter preservation mechanisms most dominant in the oceanic water column. How the samples were analyzed strongly influenced which organic matter preservation scheme appeared to dominate. Bulk functional group analysis by solid-state 13C-NMR showed that organic matter composition varied very little in light of the extreme degree of remineralization (>98%) that occurred with water column depth. This indicates preservation by a physical mechanism, such as sorption to mineral grains or protection within a mineral aggregate. However, detailed lipid studies of the characterizable fraction showed that selective preservation was important, with lipid structure being correlated with preservation over depth. However, the characterizable fraction decreases greatly with depth. Therefore, in this paper, direct temperature-resolved mass spectrometry (DT-MS), was used to further characterize POM, with the assumption that this approach could “see” a substantial proportion of the “uncharacterized” organic matter. DT-MS, which provides compositional information at an intermediate level between the detailed wet chemical studies and one-dimensional solid-state C13-NMR, also indicates an intermediate view between the mechanistic extremes of selective preservation and physical protection. 相似文献
315.
316.
Ernest S. GLADNEY Elizabeth A. JONES Eric J. NICKELL Iwan ROELANDTS 《Geostandards and Geoanalytical Research》1992,16(2):111-300
Concentration data on up to 90 individual constituents in USGS AGV-1, GSP-1, and G-2 have been collected from 1270 journal articles and technical reports. These data are summarized in consensus (mean) values with uncertainties expressed as +/- one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables. Recommended values are proposed based upon data criteria used by NIST (National Institute of Standards and Technology, formerly the National Bureau of Standards or NBS). 相似文献
317.
318.
Sediment community metabolism associated with continental shelf hypoxia, Northern Gulf of Mexico 总被引:1,自引:0,他引:1
Gilbert T. Rowe Marta Elizabeth Cruz Kaegi John W. Morse Gregory S. Boland Elva G. Escobar Briones 《Estuaries and Coasts》2002,25(6):1097-1106
Net fluxes of respiratory metabolites (O2, dissolved inorganic carbon (DIC), NH4 +, NO3 ?, and NO2 ?) across the sediment-water interface were measured using in-situ benthic incubation chambers in the area of intermittent seasonal hypoxia associated with the Mississippi River plume. Sulfate reduction was measured in sediments incubated with trace levels of35S-labeled sulfate. Heterotrophic remineralization, measured as nutrient regeneration, sediment community oxygen consumption (SOC), sulfate reduction, or DIC production, varied positively as a function of temperature. SOC was inversely related to oxygen concentration of the bottom water. The DIC fluxes were more than 2 times higher than SOC alone, under hypoxic conditions, suggesting that oxygen uptake alone cannot be used to estimate total community remineralization under conditions of low oxygen concentration in the water column. A carbon budget is constructed that compares sources, stocks, transformations, and sinks of carbon in the top meter of sediment. A comparison of remineralization processes within the sediments implicates sulfate reduction as most important, followed by aerobic respiration and denitrification. Bacteria accounted for more than 90% of the total community biomass, compared to the metazoan invertebrates, due presumably to hypoxic stress. 相似文献
319.
320.
Methane and carbon dioxide seasonal cycles during years 1998 and 1999 at two Brazilian urban and inland sites are presented. The mixing ratio averages over the studied period of time were 1.80 ppm CH4 and 384.7 ppm CO2. A comparison is made between continental averages and theaverages of the three nearest global network background sites of NOAA-CMDL comprising Ascension Island, Namibia and Easter Island. Inland sites had 0.08 ppm or 4.9% more CH4 and 19.0 ppm or 4.9% moreCO2 than background over the same time span. The CH4 summer minimum observed in remote sites was also detected inland. During the month of October 98 and 99 inland mixing ratios were frequently similar to background. 相似文献