14,900 research outputs found
The BIOEXPLOIT Project
The EU Framework 6 Integrated Project BIOEXPLOIT concerns the exploitation of natural plant biodiversity for the pesticide-free production of food. It focuses on the pathogens Phytophthora infestans, Septoria tritici, Blumeria graminis, Puccinia spp. and Fusarium spp. and on the crops wheat, barley, tomato and potato. The project commenced in October 2005, comprises 45 laboratories in 12 countries, and is carried out by partners from research institutes, universities, private companies and small-medium enterprises. The project has four strategic objectives covered in eight sub-projects. These objectives relate to (i) understanding the molecular components involved in durable disease resistance, (ii) exploring and exploiting the natural biodiversity in disease resistance, (iii) accelerating the introduction of marker-assisted breeding and genetic engineering in the EU plant breeding industry, and (iv) coordinating and integrating resistance breeding research, providing training in new technologies, disseminating the results, and transferring knowledge and technologies to the industry
Effective theory of NN interactions in a separable representation
We consider the effective field theory of the NN system in a separable
representation. The pionic part of the effective potential is included
nonperturbatively and approximated by a separable potential. The use of a
separable representation allows for the explicit solution of the
Lippmann-Schwinger equation and a consistent renormalization procedure. The
phase shifts in the channel are calculated to subleading order.Comment: 7 page
Disentangling Intertwined Embedded States and Spin Effects in Light-Front Quantization
Naive light-front quantization, carried out by a light-front energy
integration of covariant amplitudes, is not guaranteed to generate the
corresponding Feynman amplitudes. In an explicit example we show that the
nonvalence contribution to the minus-component of the EM current of a meson
with fermion constituents has a persistent end-point singularity. Only after
this term is subtracted, the result is covariant and satisfies current
conservation. If the spin-1/2 constituents are replaced by spin zero ones, the
singularity does not occur and the result is, without any adjustment, identical
to the Feynman amplitude. Numerical estimates of valence and nonvalence
contributions are presented for the cases of fermion and boson constituents.Comment: 17 pages and 9 figure
Strong coupling constant from bottomonium fine structure
From a fit to the experimental data on the fine structure, the
two-loop coupling constant is extracted. For the 1P state the fitted value is
at the scale GeV, which corresponds to the QCD constant MeV (n_f = 4) and \alpha_s(\mu_2) = 0.40 \pm 0.02(exp)\pm 0.02(th)\mu_2 = 1.02 \pm 0.2\alpha_s(1.0) \approx 0.40\alpha_s\alpha_s$ are found to be about 15%.Comment: 18 pages LaTe
The leptonic widths of high -resonances in unitary coupled-channel model
The leptonic widths of high -resonances are calculated in a
coupled-channel model with unitary inelasticity, where analytical expressions
for mixing angles between (n+1)\,^3S_1 and n\,^3D_1 states and
probabilities of the component are derived. Since these factors
depend on energy (mass), different values of mixing angles
and ,
, and are obtained. It gives
the leptonic widths ~keV,
~keV in good agreement with
experiment. For the leptonic width
~keV is calculated, while for the missing
resonance we predict ~MeV and
~keV.Comment: 10 pages, 6 references corrected, some new material adde
Higher excitations of the and mesons
The masses of higher and excitations are shown to decrease
due to the string contribution, originating from the rotation of the QCD string
itself: it lowers the masses by 45 MeV for and by 65 MeV for . An additional decrease MeV takes place if the current mass
of the light (strange) quark is used in a relativistic model. For
and the calculated masses agree with the
experimental values for and , and the masses of
, , , and are in
agreement with the new BaBar data. For the yet undiscovered resonances we
predict the masses MeV, MeV,
MeV, and MeV. We show that
for the states with and () are almost
completely unmixed (), which implies that the mixing
angles between the states with S=1 and S=0 () are for L=2 and for L=3.Comment: 22 pages, no figures, 4 tables Two references and corresponding
discussion adde
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