P. Hatcher's Books

Art as Culture

An Introduction to the Anthropology of Art

By: Evelyn P. Hatcher

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Art as Culture

An Introduction to the Anthropology of Art

By: Evelyn P. Hatcher

The concept of art as being purely for aesthetic contemplation, that is typical of industrial civilization, is not a very useful one for cross-cultural studies. The majority of the art forms that we see in museums and art books that have come from Native America or Africa or Oceania, are objects that were once part of a larger artistic whole from which they have been extracted. We need to try to piece together and imagine the artistic context as well as the cultural one if we are to attain a deeper sense of the import than the piece available to use provides. Even then, it is almost impossible to define the artistic whole. Perhaps we would do better to regard these pieces as fragments from the lifestyle of a people.

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Praeger

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ISBN 10

0897896289

ISBN 13

9780897896283

The Role of Organic Matter in Structuring Microbial Communities

By: L. Kaplan,M. Hullar,L. Sappelsa,D. Stahl,P. Hatcher,S. Frazier

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The Role of Organic Matter in Structuring Microbial Communities

By: L. Kaplan,M. Hullar,L. Sappelsa,D. Stahl,P. Hatcher,S. Frazier

Natural organic matter is important to the quality of drinking water. It constitutes precursors for disinfectant by-product formation and supports regrowth of bacteria. The drinking water industry is involved in work designed to improve biological treatment of water, control bacterial regrowth in distribution systems, and measure biodegradable NOM concentrations. These efforts would benefit from a knowledge of NOM composition and structure and the composition of microbial communities that colonize biological filters and distribution systems. In this project the researchers addressed four major goals: (1) to determine the structure and composition of natural organic matter (NOM), (2) to describe the structure of heterotrophic bacterial communities supported by raw and treated source water, (3) to measure the responses of heterotrophic bacterial communities to seasonally driven variations in NOM and temperature, and (4) to determine whether bioreactor systems can serve as small-scale models for the development and refinement of drinking water treatment processes. The five source waters selected for this project included a broad range of physiographic provinces, vegetation zones, and NOM concentrations. The research team analyzed NOM and microbial communities from an analytical hierarchy involving assessment of concentration, composition, and structure. Concentrations of NOM and BOM were estimated from dissolved organic carbon (DOC) and biodegradable DOC concentrations. NOM composition was assessed from analyses of carbohydrates with ion chromatography with pulsed amperometric detection, humic substances with XAD-8 resin, and functional groups with NMR. Molecular structure was determined from tetramethylammonium hydroxide thermochemolysis (TMAH) GC/MS. Microbial community composition was assessed from comparative ribosomal ribonucleic acid (RNA) sequencing, specifically, terminal restriction fragment length polymorphisms (t-RFLP), to provide an overview of microbial population structure and detect population shifts at the level of species. NOM Composition NOM and BOM concentrations showed extensive temporal variation in all of the source waters, but a general pattern of concentration ranges was discernable, indicating that each watershed has a particular concentration signal. Compositional studies revealed that humic substances and complex carbohydrates are components of both NOM and BOM. Structural and compositional studies identified unique NOM signatures for the different source waters, with some classes of molecules observed only in specific source waters. The BOM pool included humic substances and lignin, sources generally presumed to be relatively resistant to biodegradation. Additional novel insights included the quantitative contribution of aromatic molecules to the BOM pool and the potential for bacterial demethylation of lignin. Bacterial Communities The communities of microorganisms that developed in bioreactors that were fed water from different watersheds were unique. NOM influenced the genetic composition of resulting microbial communities, and seasonal shifts were observed for watersheds possessing strong seasonal temperature signals. Thus, temperature and organic matter quantity and quality probably influenced parameters important to the biological treatment of drinking water. A comparison of bioreactor metabolism with rapid sand filters showed some overlap, suggesting the bioreactors may indicate the ultimate potential of rapid sand filters for BOM processing. The researchers recommend the following: Bioreactors designed to monitor a BOM source should ideally be inoculated, colonized, and maintained by that source; at a minimum, acclimation to the source over several months is needed. Seasonal changes in the microbial community colonizing a biologically active filter may diminish filter performance and require an acclimation period to restore performance. Molecular-based methods for both microbial and chemical analyses of drinking water and treatment processes should be targeted for continued development and implementation within the drinking water industry. Originally published by AwwaRF for its subscribers in 2004.

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116

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IWA Publishing

Published Date

ISBN 10

1843398974

ISBN 13

9781843398974

Characterization of Total Organic Halogen Produced During Disinfection Processes

By: David A. Reckhow,G. Hua,J. Kim,P. Hatcher,S. Caccamise,R. Sachdeva

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Characterization of Total Organic Halogen Produced During Disinfection Processes

By: David A. Reckhow,G. Hua,J. Kim,P. Hatcher,S. Caccamise,R. Sachdeva

It has been known since the early 1970s that the application of disinfectants, especially chlorine, results in the formation of disinfection by-products (DBPs), most of which contain covalently bound chlorine, bromine, or iodine. These are known as the halogenated DBPs and they can be measured by a non-specific analytical method know as TOX. Despite nearly three decades of research there still remains a large fraction of DBPs that have not been identified. By comparing the TOX values with the halides attributed to known identifiable by-products (trihalomethanes [THMs], haloacetic acids [HAAs], etc.) we can estimate the unknown TOX (abbreviated here as UTOX) and better understand the formation of these unknown compounds. The objectives of this research were to (1) determine the nature and chemical characteristics of the unknown fraction of the total organic halogen (UTOX) produced during chlorination and alternative disinfection processes (i.e., chloramination, chlorine dioxide, ozone disinfection); (2) assess the impact of treatment on removal of UTOX precursors; and (3) determine the best total organic halide (TOX) protocol to use with ion chromatography (IC) analysis for the purposes of discriminating between total organic chlorine (TOCl), total organic bromine (TOBr), and total organic iodine (TOI). It was found that TOCl, TOBr, and TOI can be accurately and rapidly measured with conventional TOX instruments and an ion chromatograph. Iodide is rapidly oxidized to active iodine under a variety of treatment scenarios, and this leads to large amounts of TOI and measurable amounts of iodinated THMs. However, high levels of free chlorine can over-oxidize the iodide (forming iodate), which does not result in TOI formation. Substantial differences were noted in the tendency for various NOM fractions (hydrophobic, hydrophilic) to form specific classes of DBPs. This behavior was specific to the oxidant such that the major sources of DBP precursors for chlorination were not the same as those observed for chloramination. It was also found that corrosion control compounds can affect DBP distributions and halogen incorporation factors.

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Page Count

212

Publisher

IWA Publishing

Published Date

ISBN 10

1843398346

ISBN 13

9781843398349

Book's by P. Hatcher

Art as Culture

Art as Culture

The Role of Organic Matter in Structuring Microbial Communities

The Role of Organic Matter in Structuring Microbial Communities

Characterization of Total Organic Halogen Produced During Disinfection Processes

Characterization of Total Organic Halogen Produced During Disinfection Processes

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