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W Kilgore

Publications and source records attributed to W Kilgore.

7 recordsLinked to original sources
PubMed2001

Production of a Higgs boson accompanied by two jets via gluon fusion.

Real-emission corrections to gg-->H, which lead to H+2 jet events, are calculated at order alpha(4)(s). Contributions include top-quark triangles, boxes, and pentagon diagrams and are evaluated analytically for arbitrary top mass m(t). This new source of H+2 jet events is compared to the weak-boson fusion cross section for a range of Higgs boson masses. The heavy top-mass approximation appears to work well for intermediate Higgs-boson masses, provided that the transverse momenta of the final-state partons are smaller than the top-quark mass.

Journal Article↗
PubMed1981

Monitoring of grape harvesters for evidence of cholinesterase inhibition.

This report describes the results of a long-term monitoring study of 36 grape harvesters who were occupationally exposed to organophosphate pesticide residues following reentry into vineyards during September and October 1976. The study was designed to evaluate biochemical parameters associated with organophosphate pesticide residues. Insignificant changes in blood cholinesterase activity were found. Some workers had very low levels of organophosphate metabolites in the urine during the entire 6 wk of study. Ethion dioxon was the only pesticide residue detected on the grape leaves. The harvesting of wine grapes involves numerous work crews of four to six people each, requiring a highly mobile monitoring staff. A single stationary location for collecting blood and urine samples will result in massive losses to follow-up since the workers cannot be relied on to report on their own. It is recommended that, to maximize worker cooperation, future monitoring studies rely more on analyses of urine specimens and less on venipuncture for evidence of pesticide exposure.

Adolescent↗
PubMed1980

Excretion and storage of [14C]toxaphene and two isolated [14C]toxaphene fractions.

The 7-d urinary and fecal excretions of [14C]toxaphene and two isolated [14C]toxaphene fractions (polar fraction 7 and nonpolar fraction 2) were determined in orally dosed rats. The urinary, fecal, and total excretions of toxaphene were, respectively, 22.5, 35.7, and 58.2% of the administered dose. The total excretions of fractions 2 and 7 were, respectively, 69.4 and 65.0%, and the overall order of excretion was fraction 2 greater than toxaphene greater than fraction 7. All three groups had low toxaphene levels (below 0.2 ppm) in all tissues analyzed except for fat, where significant levels were detected. Hexane and chloroform extracts of the urine revealed that the activity was more polar than the parent material for all three groups. Apparently, toxaphene must be metabolized before it can be excreted in the urine. When fat extracts were analyzed by thin-layer chromatography and autoradiography, differences were found between the parent material and the extracted activity. There was an increase in polar activity in the residue obtained from toxaphene-treated rats. The fat from the fraction 2 group contained fraction 2 and two additional more polar spots, which represented about 11% of the total activity. The fat from the fraction 7 group also contained two additional spots, but they were less polar than fraction 7. Apparently, the metabolism of fraction 7 results in some products that are less polar and, perhaps, more persistent.

Adipose Tissue↗
PubMedDate not supplied

Epidemiologic study of physiological effects in usual and volunteer citrus workers from organophosphate pesticide residues at reentry.

Biological parameters associated with organophosphate (OP) pesticide exposure were evaluated in a study of citrus harvesters. Changes in these parameters related to environmental residues of cholinesterase (ChE) inhibiting pesticides were studied. Further, it was determined whether usual and volunteer workers differed in their biochemical parameters after exposure to pesticide residues during field operations. Urine metabolite findings for usual farm workers showed that some exposure to OP pesticides had occurred. Too few workers were available during the reentry stage of the field study to evaluate the effect of this exposure on blood ChE. Baseline (nonexposure) acetylcholinesterase (AChE) and plasma cholinesterase (PChE) activities were significantly higher in usual (Mexican American) workers than in volunteer workers (student volunteers). Student volunteers in the test citrus grove showed statistically significant declines in PChE during the exposure period, yet changes in AChE activity, urine metabolites, and residue levels were very small. The implications of these findings are discussed in light of current reentry standards as well as future epidemiologic studies on reentry research.

Cholinesterases↗