55 research outputs found
Research seeks to expand new fishery
(...) In 1940, the ribbed mussels, Volsella demissus, of Tidewater Virginia were discovered by Du Pont chemists to be rich in this provitamin D. This discovery was followed immediately by the development of a mussel fishery on the Seaside of Virginia\u27s Eastern Shore peninsula, the activity centering on the large intertidal marshes where the mussels grow and in the shucking houses along the water fronts of shore towns where the mussels are steamed, shucked, and packed for shipment. This fishery has since constituted the country\u27s principal available provitamin D source, and large war demands for eggs and poultry meat have been met by the poultry industry with the help of the previously unexploited Virginia mussels.
Because of the prospective importance of the mussel, the Du Pont company acted through the-Virginia Fisheries Laboratory in 1940 to initiate a biological study of this as yet little-known bivalve
Report on Studies of Oyster Parasites in the Aransas Bay and Galveston Bay areas of Texas
The first collection of oyster for this study was taken off Fulton Beach, Aransas Bay on January 1, 1962. Subsequently, 34 collections were made, most of them in Aransas Bay, but several collections were made in Mesquite, Tres Palacios, Corpus Christi, and Galveston Bays. These oysters were sectioned and slides made, a total of more than 1300. All collections were of live oysters, and the reading of the slides was a slow process. Live oysters were used because the platforms which were to hold trays of oysters were delayed in construction. Hence, no data on mortality are available. The period from January 1, 1962, to June 26, 1962, was used to determine roughly from the slides what parasites and diseases were present and where they were located. The data on collections are listed in Table 1
Search for single top quarks in the tau+jets channel using 4.8 fb of collision data
We present the first direct search for single top quark production using tau
leptons. The search is based on 4.8 fb of integrated luminosity
collected in collisions at =1.96 TeV with the D0 detector
at the Fermilab Tevatron Collider. We select events with a final state
including an isolated tau lepton, missing transverse energy, two or three jets,
one or two of them tagged. We use a multivariate technique to discriminate
signal from background. The number of events observed in data in this final
state is consistent with the signal plus background expectation. We set in the
tau+jets channel an upper limit on the single top quark cross section of
\TauLimObs pb at the 95% C.L. This measurement allows a gain of 4% in expected
sensitivity for the observation of single top production when combining it with
electron+jets and muon+jets channels already published by the D0 collaboration
with 2.3 fb of data. We measure a combined cross section of
\SuperCombineXSall pb, which is the most precise measurement to date.Comment: 12 pages, 5 figure
Measurement of Z/gamma*+jet+X angular distributions in ppbar collisions at sqrt{s}=1.96 TeV
We present the first measurements at a hadron collider of differential cross
sections for Z+jet+X production in delta phi(Z, jet), |delta y(Z, jet)| and
|y_boost(Z, jet)|. Vector boson production in association with jets is an
excellent probe of QCD and constitutes the main background to many small cross
section processes, such as associated Higgs production. These measurements are
crucial tests of the predictions of perturbative QCD and current event
generators, which have varied success in describing the data. Using these
measurements as inputs in tuning event generators will increase the
experimental sensitivity to rare signals.Comment: Published in Physics Letters B 682 (2010), pp. 370-380. 15 pages, 6
figure
Search for the standard model Higgs boson in tau final states
We present a search for the standard model Higgs boson using hadronically
decaying tau leptons, in 1 inverse femtobarn of data collected with the D0
detector at the Fermilab Tevatron ppbar collider. We select two final states:
tau plus missing transverse energy and b jets, and tau+ tau- plus jets. These
final states are sensitive to a combination of associated W/Z boson plus Higgs
boson, vector boson fusion and gluon-gluon fusion production processes. The
observed ratio of the combined limit on the Higgs production cross section at
the 95% C.L. to the standard model expectation is 29 for a Higgs boson mass of
115 GeV.Comment: publication versio
Search for W' bosons decaying to an electron and a neutrino with the D0 detector
This Letter describes the search for a new heavy charged gauge boson W'
decaying into an electron and a neutrino. The data were collected with the D0
detector at the Fermilab Tevatron proton-antiproton Collider at a
center-of-mass energy of 1.96 TeV, and correspond to an integrated luminosity
of about 1 inverse femtobarn. Lacking any significant excess in the data in
comparison with known processes, an upper limit is set on the production cross
section times branching fraction, and a W' boson with mass below 1.00 TeV can
be excluded at the 95% C.L., assuming standard-model-like couplings to
fermions. This result significantly improves upon previous limits, and is the
most stringent to date.Comment: submitted to Phys. Rev. Let
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