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... Continuous flow centrifugation (CFC) was used in conjunction with immunomagnetic separation (IMS) and immunofluorescence microscopy (IFA) and nested PCR to recover and detect oocysts of Cryptosporidium parvum and cysts of Giardia intestinalis from 10 L volumes of source water samples. Using a spiking dose of 100 oocysts, nine of 10 runs were positive by IFA, with a mean recovery of 4.4±2.27 oocyst ...
Escherichia coli; irrigation water; microbial contamination; point source pollution; water pollution; genetic variation; microbial genetics; microbial genetic resources; feces; sediment contamination; gel electrophoresis; genetic stability; irrigation canals; mortality; DNA fingerprinting; Rio Grande River; Texas; Mexico
Abstract:
... Identifying the sources of fecal contaminants in surface water bodies such as rivers and lakes is of significant importance for environmental quality, food safety and regulatory purposes. Current DNA library-based source tracking approaches rely on the comparison of the genetic relatedness among the fecal contaminants. The objective of this study was to determine the genetic relatedness of Escheri ...
... The use of cellulose-containing agricultural by-products modified with the cross-linking reagent dimethyloldihydroxyethylene urea (DMDHEU) and the quaternary amine, choline chloride, as anion exchange resins, has not been reported. The objective of the present study was to convert the readily available by-products, soybean hulls, sugarcane bagasse and corn stover to functional anion exchange resin ...
soil pollution; mineral soils; organic soils; soil chemical properties; dissolved organic carbon; disinfectants; carcinogens; extraction; filtration; cations; California
Abstract:
... Filters with a pore size of 0:45 mm have been arbitrarily used for isolating dissolved organic carbon (DOC) in natural waters. This operationally defined DOC fraction often contains heterogeneous organic carbon compounds that may lead to inconsistent results when evaluating trihalomethane formation potential (THMFP). A finer pore size filter provides more homogeneous DOC properties and enables a b ...
drinking water; water treatment; disinfection; Adenoviridae; Feline calicivirus; ozone; ozonation
Abstract:
... Little information is available regarding the effectiveness of ozone on the inactivation of caliciviruses and enteric adenoviruses. Inactivation experiments were conducted with feline calicivirus (FCV), closely related to the human caliciviruses based on nucleic acid organization and capsid architecture, and adenovirus type 40 (AD40). Experiments were carried out in buffered disinfectant demand fr ...
groundwater contamination; community structure; sulfates; heavy metals; bioremediation; wastewater treatment; sulfate-reducing bacteria; industrial effluents; microbial activity; mine spoil
Abstract:
... Permeable reactive barrier (PRB) technology, in which sulfate-reducing bacteria (SRB) facilitate precipitation of metal sulfides, is a promisingapproach for remediation of sulfate- and metal-laden mine drainage. While PRBs are easily established, they often decline for reasons not well understood. SRB depend on or compete with multiple dynamic microbial populations within a PRB; as a result, perfo ...