2,579 research outputs found
Genetic improvement of wheat for dry environments - a trait based approach
Item does not contain fulltext23 januari 201
NLO QCD corrections to WZ+jet production with leptonic decays
We compute the next-to-leading order QCD corrections to WZ+jet production at
the Tevatron and the LHC, including decays of the electroweak bosons to light
leptons with all off-shell effects taken into account. The corrections are
sizable and have significant impact on the differential distributions.Comment: 14 pages, 7 figure
Tensorial Reconstruction at the Integrand Level
We present a new approach to the reduction of one-loop amplitudes obtained by
reconstructing the tensorial expression of the scattering amplitudes. The
reconstruction is performed at the integrand level by means of a sampling in
the integration momentum. There are several interesting applications of this
novel method within existing techniques for the reduction of one-loop multi-leg
amplitudes: to deal with numerically unstable points, such as in the vicinity
of a vanishing Gram determinant; to allow for a sampling of the numerator
function based on real values of the integration momentum; to optimize the
numerical reduction in the case of long expressions for the numerator
functions.Comment: 20 pages, 2 figure
Polymorphisms of SP110 are associated with both pulmonary and extra-pulmonary tuberculosis among the Vietnamese
Background: Tuberculosis (TB) is an infectious disease that remains a major cause of morbidity and mortality worldwide, yet the reasons why only 10% of people infected with Mycobacterium tuberculosis go on to develop clinical disease are poorly understood. Genetically determined variation in the host immune response is one factor influencing the response to M. tuberculosis. SP110 is an interferon-responsive nuclear body protein with critical roles in cell cycling, apoptosis and immunity to infection. However association studies of the gene with clinical TB in different populations have produced conflicting results. Methods: To examine the importance of the SP110 gene in immunity to TB in the Vietnamese we conducted a case-control genetic association study of 24 SP110 variants, in 663 patients with microbiologically proven TB and 566 unaffected control subjects from three tertiary hospitals in northern Vietnam. Results: Five SNPs within SP110 were associated with all forms of TB, including four SNPs at the C terminus (rs10208770, rs10498244, rs16826860, rs11678451) under a dominant model and one SNP under a recessive model, rs7601176. Two of these SNPs were associated with pulmonary TB (rs10208770 and rs16826860) and one with extra-pulmonary TB (rs10498244). Conclusion: SP110 variants were associated with increased susceptibility to both pulmonary and extra-pulmonary TB in the Vietnamese. Genetic variants in SP110 may influence macrophage signaling responses and apoptosis during M. tuberculosis infection, however further research is required to establish the mechanism by which SP110 influences immunity to tuberculosis infection. © 2014 Fox et al
The risk of secondary traumatic stress in the qualitative transcription process: A research note.
Kiyimba, N. & O'Reilly, M., The risk of secondary traumatic stress in the qualitative transcription process: a research note, Qualitative Research (16:4) pp. 468-476. Copyright © Nikki Kiyimba & Michelle O'Reilly, 2015. Reprinted by permission of SAGE Publications.It is recognised that transcribing is not merely a neutral and mechanical process, but is active and requires careful engagement with the qualitative data. Whether the researcher transcribes their own data or employs professional transcriptionists the process requires repeated listening to participantsâ personal narratives. This repetition has a cumulative effect on the transcriptionist and hearing the participantsâ personal narratives of a sensitive or distressing nature, can have an emotional impact. However, this potential emotional impact is often not something which is accounted for in the planning stages of research. In this article we critically discuss the importance of considering the effects on transcriptionists who engage with qualitative data
Supersymmetric Monojets at the Large Hadron Collider
Supersymmetric monojets may be produced at the Large Hadron Collider by the
process qg -> squark neutralino_1 -> q neutralino_1 neutralino_1, leading to a
jet recoiling against missing transverse momentum. We discuss the feasibility
and utility of the supersymmetric monojet signal. In particular, we examine the
possible precision with which one can ascertain the neutralino_1-squark-quark
coupling via the rate for monojet events. Such a coupling contains information
on the composition of the neutralino_1 and helps bound dark matter direct
detection cross-sections and the dark matter relic density of the neutralino_1.
It also provides a check of the supersymmetric relation between gauge couplings
and gaugino-quark-squark couplings.Comment: 46 pages, 10 figures. The appendix has been rewritten to correct an
error that appears in all previous versions of the appendix. This error has
no effect on the results in the main body of the pape
Single Cut Integration
We present an analytic technique for evaluating single cuts for one-loop
integrands, where exactly one propagator is taken to be on shell. Our method
extends the double-cut integration formalism of one-loop amplitudes to the
single-cut case. We argue that single cuts give meaningful information about
amplitudes when taken at the integrand level. We discuss applications to the
computation of tadpole coefficients.Comment: v2: corrected typo in abstrac
Potential Sensitivity of Gamma-Ray Burster Observations to Wave Dispersion in Vacuo
The recent confirmation that at least some gamma-ray bursters (GRBs) are
indeed at cosmological distances raises the possibility that observations of
these could provide interesting constraints on the fundamental laws of physics.
Here we demonstrate that the fine-scale time structure and hard spectra of GRB
emissions are very sensitive to the possible dispersion of electromagnetic
waves in vacuo with velocity differences \delta v \sim E/E_{\QG}, as
suggested in some approaches to quantum gravity. A simple estimate shows that
GRB measurements might be sensitive to a dispersion scale comparable
to the Planck energy scale GeV, sufficient to test some of
these theories, and we outline aspects of an observational programme that could
address this goal.Comment: LaTex. 9 pages. Version accepted for publication in Nature. (A few
changes to the reference list. Additional comments on the analyticity
properties of the dispersion law.
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