492 research outputs found
IEEE SA Industry Connections 3D Body Processing Working Group and IEEE P3141 Standard for 3D Body Processing - Part 1
Mcdonald, C.; Rannow, RK.; Pai, D.; Bullas, A.; Ballester Fernandez, A. (2020). IEEE SA Industry Connections 3D Body Processing Working Group and IEEE P3141 Standard for 3D Body Processing - Part 2. IEEE Consumer Electronics Magazine. 9(6):97-99. https://doi.org/10.1109/MCE.2020.2997556S97999
Use of cultivar resistance and crop rotation with Bacillus subtilis for clubroot control in canola
Non-Peer ReviewedThis study was conducted to assess additional strategies potentially complimentary to cultivar
resistance or biocontrol in control of clubroot. New granular Bacillus subtilis formulations
and a seed dressing method were developed to facilitate biofungicide delivery in field trials.
The granular formulations were applied in furrow during seeding at 50 kg/ha to a clubroot
resistant (CR) and susceptible (CS) canola cultivar, respectively, in three field trials. The seed
dressing applied approximately 1Ă—105 to 5Ă—106 cfu/seed doses of the biocontrol agent, and
was evaluated on the CS cultivar seeded to different crop-rotation scenarios where the plots
had a 1-year, 3-year, or 11-year break from last canola crop. Clubroot disease pressure was
high at all trial sites with disease severity indexes (DSI) ranging from 69% to 98% on the CS
cultivar. None of the granular formulations reduced clubroot substantially, whereas the CR
cultivar showed a high effect, reducing DSI to below 15% and doubling the yield over that of
CS cultivar. Plots of varying rotation showed a pattern of clubroot pathogen pressure, with
those of 1-year break from canola being the highest. The DSI for all rotational scenarios was
high, reaching 100% in short-rotation plots. Biofungicide seed dressing did not reduce DSI,
but longer crop rotation often reduced gall size slightly, showed much milder above-ground
damage, and increased the yield significantly relative to short rotation in two separate trials.
Even a 3-year break from canola was highly beneficial, with the yield doubled as opposed to
that with only 1-year break from canola
Direct detection of Higgs-portal dark matter at the LHC
We consider the process in which a Higgs particle is produced in association
with jets and show that monojet searches at the LHC already provide interesting
constraints on the invisible decays of a 125 GeV Higgs boson. Using the
existing monojet searches performed by CMS and ATLAS, we show the 95%
confidence level limit on the invisible Higgs decay rate is of the order of the
total Higgs production rate in the Standard Model. This limit could be
significantly improved when more data at higher center of mass energies are
collected, provided systematic errors on the Standard Model contribution to the
monojet background can be reduced. We also compare these direct constraints on
the invisible rate with indirect ones based on measuring the Higgs rates in
visible channels. In the context of Higgs portal models of dark matter, we then
discuss how the LHC limits on the invisible Higgs branching fraction impose
strong constraints on the dark matter scattering cross section on nucleons
probed in direct detection experiments.Comment: 6 pages, 3 figures; v2: references added; v3: monojet and Higgs data
updated, version published in EPJ
Radial profile of the 3.5 keV line out to R_200 in the perseus cluster
GalaxiesTheoretical Physic
Search for R-Parity Violating Decays of Scalar Fermions at LEP
A search for pair-produced scalar fermions under the assumption that R-parity
is not conserved has been performed using data collected with the OPAL detector
at LEP. The data samples analysed correspond to an integrated luminosity of
about 610 pb-1 collected at centre-of-mass energies of sqrt(s) 189-209 GeV. An
important consequence of R-parity violation is that the lightest supersymmetric
particle is expected to be unstable. Searches of R-parity violating decays of
charged sleptons, sneutrinos and squarks have been performed under the
assumptions that the lightest supersymmetric particle decays promptly and that
only one of the R-parity violating couplings is dominant for each of the decay
modes considered. Such processes would yield final states consisting of
leptons, jets, or both with or without missing energy. No significant
single-like excess of events has been observed with respect to the Standard
Model expectations. Limits on the production cross- section of scalar fermions
in R-parity violating scenarios are obtained. Constraints on the supersymmetric
particle masses are also presented in an R-parity violating framework analogous
to the Constrained Minimal Supersymmetric Standard Model.Comment: 51 pages, 24 figures, Submitted to Eur. Phys. J.
Measurement of the Hadronic Photon Structure Function F_2^gamma at LEP2
The hadronic structure function of the photon F_2^gamma is measured as a
function of Bjorken x and of the factorisation scale Q^2 using data taken by
the OPAL detector at LEP. Previous OPAL measurements of the x dependence of
F_2^gamma are extended to an average Q^2 of 767 GeV^2. The Q^2 evolution of
F_2^gamma is studied for average Q^2 between 11.9 and 1051 GeV^2. As predicted
by QCD, the data show positive scaling violations in F_2^gamma. Several
parameterisations of F_2^gamma are in agreement with the measurements whereas
the quark-parton model prediction fails to describe the data.Comment: 4 pages, 2 figures, to appear in the proceedings of Photon 2001,
Ascona, Switzerlan
A measurement of the tau mass and the first CPT test with tau leptons
We measure the mass of the tau lepton to be 1775.1+-1.6(stat)+-1.0(syst.) MeV
using tau pairs from Z0 decays. To test CPT invariance we compare the masses of
the positively and negatively charged tau leptons. The relative mass difference
is found to be smaller than 3.0 10^-3 at the 90% confidence level.Comment: 10 pages, 4 figures, Submitted to Phys. Letts.
First Measurement of Z/gamma* Production in Compton Scattering of Quasi-real Photons
We report the first observation of Z/gamma* production in Compton scattering
of quasi-real photons. This is a subprocess of the reaction e+e- to
e+e-Z/gamma*, where one of the final state electrons is undetected.
Approximately 55 pb-1 of data collected in the year 1997 at an e+e-
centre-of-mass energy of 183 GeV with the OPAL detector at LEP have been
analysed. The Z/gamma* from Compton scattering has been detected in the
hadronic decay channel. Within well defined kinematic bounds, we measure the
product of cross-section and Z/gamma* branching ratio to hadrons to be
(0.9+-0.3+-0.1) pb for events with a hadronic mass larger than 60 GeV,
dominated by (e)eZ production. In the hadronic mass region between 5 GeV and 60
GeV, dominated by (e)egamma* production, this product is found to be
(4.1+-1.6+-0.6) pb. Our results agree with the predictions of two Monte Carlo
event generators, grc4f and PYTHIA.Comment: 18 pages, LaTeX, 5 eps figures included, submitted to Physics Letters
Measurement of the B0 Lifetime and Oscillation Frequency using B0->D*+l-v decays
The lifetime and oscillation frequency of the B0 meson has been measured
using B0->D*+l-v decays recorded on the Z0 peak with the OPAL detector at LEP.
The D*+ -> D0pi+ decays were reconstructed using an inclusive technique and the
production flavour of the B0 mesons was determined using a combination of tags
from the rest of the event. The results t_B0 = 1.541 +- 0.028 +- 0.023 ps, Dm_d
= 0.497 +- 0.024 +- 0.025 ps-1 were obtained, where in each case the first
error is statistical and the second systematic.Comment: 17 pages, 4 figures, submitted to Phys. Lett.
Search for Higgs Bosons in e+e- Collisions at 183 GeV
The data collected by the OPAL experiment at sqrts=183 GeV were used to
search for Higgs bosons which are predicted by the Standard Model and various
extensions, such as general models with two Higgs field doublets and the
Minimal Supersymmetric Standard Model (MSSM). The data correspond to an
integrated luminosity of approximately 54pb-1. None of the searches for neutral
and charged Higgs bosons have revealed an excess of events beyond the expected
background. This negative outcome, in combination with similar results from
searches at lower energies, leads to new limits for the Higgs boson masses and
other model parameters. In particular, the 95% confidence level lower limit for
the mass of the Standard Model Higgs boson is 88.3 GeV. Charged Higgs bosons
can be excluded for masses up to 59.5 GeV. In the MSSM, mh > 70.5 GeV and mA >
72.0 GeV are obtained for tan{beta}>1, no and maximal scalar top mixing and
soft SUSY-breaking masses of 1 TeV. The range 0.8 < tanb < 1.9 is excluded for
minimal scalar top mixing and m{top} < 175 GeV. More general scans of the MSSM
parameter space are also considered.Comment: 49 pages. LaTeX, including 33 eps figures, submitted to European
Physical Journal
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