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1.
Molecular methods, including DNA probes, were used to identify and enumerate pathogenic Vibrio species in the Chesapeake Bay; our data indicated that Vibrio vulnificus exhibits seasonal fluctuations in number. Our work included a characterization of total microbial communities from the Bay; development of microarrays that identify and quantify the diversity of those communities; and observation of temporal changes in those communities. To identify members of the microbial community, we amplified the 16S rDNA gene from community DNA isolated from a biofilm sample collected from the Chesapeake Bay in February, 2000. The resultant 75 sequences were 95% or more similar to 7 species including two recently described Shewanella species, baltica and frigidimarina, that have not been previously isolated from the Chesapeake. When the genera of bacteria from biofilm after culturing are compared to those detected by subcloning amplified 16S fragments from community DNA, the cultured sample exhibited a strong bias. In oysters collected in February, the most common bacteria were previously unknown. Based on our 16S findings, we are developing microarrays to detect these and other microbial species in these estuarine communities. The microarrays will detect each species using four distinct loci, with the multiple loci serving as an internal control. The accuracy of the microarray will be measured using sentinel species such as Aeromonas species, Escherichia coli, and Vibrio vulnificus. Using microarrays, it should be possible to determine the annual fluctuations of bacterial species (culturable and non-culturable, pathogenic and non-pathogenic). The data may be applied to understanding patterns of environmental change; assessing the health of the Bay; and evaluating the risk of human illness associated with exposure to and ingestion of water and shellfish.  相似文献   
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Fast pyrolysis of chicken manure produced two biooils (Fractions I and II) and a residual char. All four materials were analyzed by chemical methods, 13C and 1H Nuclear Magnetic Resonance Spectrometry (13C and 1H NMR), and Fourier Transform Infrared Spectrosphotometry (FTIR). The char showed the highest C content and the highest aromaticity. Of the two biooils Fraction II was higher in C, yield and calorific value but lower in N than Fraction I. The S and ash content of the two biooil fractions were low. The Cross Polarization Magic Angle Spinning (CP-MAS) 13C NMR spectrum of the initial chicken manure showed it to be rich in cellulose, which was a major component of sawdust used as bedding material. Nuclear Magnetic Resonance (NMR) spectra of the two biooils indicated that Fraction I was less aromatic than Fraction II. Among the aromatics in the two biooils, we were able to tentatively identify N-heterocyclics like indoles, pyridines, and pyrazines. FTIR spectra were generally in agreement with the NMR data. FTIR spectra of both biooils showed the presence of both primary and secondary amides and primary amines as well as N-heterocyclics such as pyridines, quinolines, and pyrimidines. The FTIR spectrum of the char resembled that of the initial chicken manure except that the concentration of carbohydrates was lower.  相似文献   
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Abstract

Disappearance rates of 10 ppm technical diflubenzuron (N(((4‐chloro‐phenyl)amino)carbonyl)‐2,6‐diflurobenzamide, Dimilin®) and BAY SIR 8514 (2‐chloro‐N(((4‐trifluoromethoxyphenyl)amino)carbonyl)benzamide) applied on quartz sand to natural sandy loam and muck soils were significantly greater than for the corresponding sterilized soils, e.g. 47–51% vs. 68–87% BAY SIR 8514 and 2–12% vs. 80–87% diflubenzuron remaining at 12 wk, indicating that soil microorganisms play a major role in their degradation. Kinetic analysis of the data based on a first order dependence on the insecticide concentration showed that the rate constants for these disappearance reactions decreased with time.  相似文献   
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Morris DF  Krishnan N 《Ambio》2012,41(Z1):90-99
The need for transparency is taking more prominence in international climate negotiations as developed countries pledge large sums of money to foster adaptation efforts in developing countries. Tools that provide accurate and up-to-date spatial information that can be easily used and vetted by local practitioners may provide effective and affordable ways to improve transparency. The Global Adaptation Atlas is such a tool, combining vetted, publicly available climate impact data with timely maps of on the ground adaptation projects to highlight confluences of effects of climate change with actions taken to address those effects. Here, we describe the structure and general functions of the Global Adaptation Atlas and explain how it may be utilized to track short-term investments in adaptation. Over longer time scales, it may also help gauge the effectiveness of specific adaptation investments as well as reveal how different climate impacts affect long-term investment in differing regions.  相似文献   
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Field experience with the lead acetate impregnated paper tape sampler has indicated that large errors may arise in this method due to fading of the color of the precipitated lead sulfide spots. This fading is due to the action of light, sulfur dioxide, ozone, on other substances capable of oxidizing lead sulfide. The moisture content or relative humidity of the air sample must be maintained at an appropriate level to ensure reaction with the impregnated paper tape. The effects of the factors have been investigated in laboratory experiments with known concentrations of H2S. A number of antioxidants were studied in relation to the stability of the resultant spots to light and oxidation Orthophenyl phenol was found to be the most effective antioxidant for this purpose. A number of necessary precautions to be employed in the use of the lead acetate method are recommended and the limitations are discussed.  相似文献   
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The results from the regional air quality analysis for the Four Corners Study are discussed in this paper. This study was one of five regional studies conducted for the National Commission on Air Quality. Potential regional air quality impacts were evaluated through the year 1995 for alternative energy scenarios under current and alternative regulatory policies. The alternative regulatory policies include emission fees, technology standards, emission ceilings, and prevention of significant deterioration class elimination. The alternatives were compared in terms of their impacts on regional visibility and on the ambient concentrations of SO2, SO4, and primary fine particulates. The fate of the pollutants was estimated. The alternative regulatory policies were quite different with respect to their control of SOX emissions and their impacts on regional visibility. Sources located outside of the study region were estimated to have a major impact on regional air quality within the study region.  相似文献   
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