Publications by authors named "Whitehand L"

Studies were conducted with ozone gas fumigation under vacuum as a methyl bromide alternative against life stages of coffee berry borer (CBB) Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae), and the urediniospores of coffee leaf rust (CLR), Hemileia vastatrix Berkeley & Broome (Basidiomycota: Pucciniales) in green coffee, Coffea spp. L. Fumigation with 10,000 ppm O3 gas under -25.

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Background: Mineral nutrition during wheat grain development has large effects on wheat flour protein content and composition, which in turn affect flour quality and immunogenic potential for a commodity of great economic value. However, it has been difficult to define the precise effects of mineral nutrition on protein composition because of the complexity of the wheat flour proteome. Recent improvements in the identification of flour proteins by tandem mass spectrometry (MS/MS) and the availability of a comprehensive proteome map of flour from the US wheat Butte 86 now make it possible to document changes in the proportions of individual flour proteins that result from the application of mineral nutrition.

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Multilocus variable-number tandem-repeat analysis (MLVA) is used for source tracking Escherichia coli O157:H7 in agricultural environments. Tandem repeats were stable after limited replication but changed after exposure to irradiation, elevated temperatures, and starvation conditions. The pO157 plasmid was frequently lost under these stress conditions.

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Three tasty (BR-139, FA-624, and FA-612) and two less tasty (R-144 and R-175) fresh greenhouse tomato cultivars, which significantly differ in their flavor profiles, were screened for potent odorants using aroma extract dilution analysis (AEDA). On the basis of AEDA results, 19 volatiles were selected for quantification in those 5 cultivars using gas chromatography-mass spectrometry (GC-MS). Compounds such as 1-penten-3-one, ( E, E)- and ( E, Z)-2,4-decadienal, and 4-hydroxy-2,5-dimethyl-3(2 H)-furanone (Furaneol) had higher odor units in the more preferred cultivars, whereas methional, phenylacetaldehyde, 2-phenylethanol, or 2-isobutylthiazole had higher odor units in the less preferred cultivars.

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Aims: This study compared the chemical, physical and bacterial composition of circulated and stagnant dairy wastewaters.

Methods And Results: Samples taken from circulated and stagnant wastewater lagoons, over a 1-year period, were analysed for 10 chemical (total N, NH3, NO3, NO2, Na, Ca, HCO3, Fe, P and K) and six physical (biological oxygen demand, chemical oxygen demand, dissolved solids, electrical conductivity, pH and sodium absorption ratio) parameters and were found to be similar. The 16S rDNA genes from the samples were amplified, cloned and BLAST analysed.

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The effects of methyl bromide (MB) concentration (16, 32,48, or 64 g/m3), fumigation temperature (15, 20, 25, or 30 degrees C), and fumigation time interactions on the survival of Mediterranean fruit fly, Ceratitis capitata (Wiedemann), and oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), eggs and first and third instars were recorded. Increasing the fumigation temperature from 15 to 20 degrees C or from 20 to 25 degrees C resulted in a significant reduction in fumigation time required for equivalent egg and larval mortalities at all studied MB concentrations; no further reductions in fumigation time resulted from increasing the temperature from 25 to 30 degrees C. Conversely, increasing temperature and time allowed for a reduction in MB concentration to obtain equivalent mortality.

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The aim of this work was to optimize a supercritical fluid extraction (SFE)/enzymatic reaction process for the determination of the fatty acid composition of castor seeds. A lipase from Candida antarctica (Novozyme 435) was used to catalyze the methanolysis reaction in supercritical carbon dioxide (SC-CO(2)). A Box-Behnken statistical design was used to evaluate effects of various values of pressure (200-400 bar), temperature (40-80 degrees C), methanol concentration (1-5 vol %), and water concentration (0.

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Methyl eugenol (4-allyl-1,2-dimethoxybenzene-carboxylate) and cue-lure [4-(p-acetoxyphenyl)-2-butanone] are highly attractive kairomone lures to oriental fruit fly, Bactrocera dorsalis (Hendel), and melon fly, B. cucurbitae (Coquillett), respectively. Plastic bucket traps were evaluated as dispensers for methyl eugenol and cue-lure for suppression of the 2 fruit flies in Hawaii.

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Fenbendazole residues in bovine milk were analyzed by ELISAs using two monoclonal antibodies. One monoclonal antibody (MAb 587) bound the major benzimidazole anthelmintic drugs, including fenbendazole, oxfendazole, and fenbendazole sulfone. The other (MAb 591) was more specific for fenbendazole, with 13% cross-reactivity with the sulfone and no significant binding to the sulfoxide metabolite.

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Numerous Salmonella enterica and Escherichia coli O157:H7 outbreaks have been associated with contaminated sprouts. We examined how S. enterica serovars, E.

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Preharvest contamination of field crops may have many sources, including feces, soil, and irrigation water. In March 2000, a sewage spill released unchlorinated tertiary-treated effluent into a creek used to irrigate commercial produce. A field of young cabbage transplants was irrigated with creek water as the contaminated water flowed past this land.

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Recent foodborne outbreaks have linked infection by enterohemorrhagic Escherichia coli (EHEC) serotype O157:H7 to the consumption of contaminated lettuce. Contamination via food handler error and on-the-farm contamination are thought to be responsible for several outbreaks. Though recent studies have examined the application of EHEC to store-bought lettuce, little is known about the attachment of EHEC to growing plants.

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The use of a fluorescent stain containing Hoechst 33258 and pyronin Y in the fetal mouse transplacental micronucleus assay allows classification of erythrocytes into three subpopulations on the basis of RNA staining, and permits micronuclei to be scored in all three subpopulations. The youngest erythrocytes stain uniformly positive for RNA (UEs). In older erythrocytes RNA aggregates to give the cells a stippled appearance (SEs) and ultimately disappears, leaving cells which do not stain positively for RNA.

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Measurements of second-stage juveniles of Heterodera schachtii from California and The Netherlands and a race of H. trifolii from The Netherlands were obtained and compared to determine if these populations can be differentiated by morphometrics. Juvenile lengths of 10 specimens from each of 10 cysts of each population were measured.

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A bioassay is described for determining medicagenin-type saponin in dried alfalfa, leaf protein concentrates, and alfalfa sprouts. Samples are extracted by refluxing 2 1/2 hr with 50% ethanol, ethanol is evaporated, and aliquots of an aqueous solution are added to potato dextrose agar (PDA) and assayed for saponin by using the fungus Trichoderma viride. The growth of the fungus on PDA is compared with a standard saponin, and saponin levels are calculated by means of a slope ratio analysis.

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