361 research outputs found
Advances in synchronized XML-media wiki dictionary development in the context of endangered uralic languages
Peer reviewe
Towards an open-source universal-dependency treebank for Erzya
This article describes the first steps towards a open-source dependency tree- bank for Erzya based on universal dependency (UD) annotation standards. The treebank contains 610 sentences with 6661 tokens and is based on texts from a range of open-source and public domain original Erzya sources. This ensures its free availability and extensibility. Texts in the treebank are first morphologically analyzed and disambiguated after which they are annotated manually for depen- dency structure. In the article we present some issues in dependency syntax for Erzya and how they are analyzed in the universal-dependency framework. Pre- liminary statistics are given for dependency parsing of Erzya, along with points of interest for future research.Peer reviewe
Gamma*Gamma* Reactions at High Energies
The total hadronic gamma*gamma* cross sections at high energy are calculated
as a function of energy and photon virtuality in a model combining Regge
exchange, the quark box diagram (a fixed pole in Regge language) and soft and
hard pomeron exchanges evaluated in the context of dipole-dipole scattering.
Good agreement is obtained with the data for the real gamma-gamma cross section
and for the real photon structure function. However the model prediction for
the gamma* gamma* cross section is too small. This is attributed to an
incorrect extrapolation of the Q^2 dependence of the hard pomeron adopted here.
Parametrising it independently shows that the hard part of the cross section
can be well represented by a simple Regge pole with intercept ~ 1.3.Comment: 21 pages, 5 figure
Odd C-P contributions to diffractive processes
We investigate contributions to diffractive scattering, which are odd under
C- and P-parity. Comparison of p- and p-p scattering indicates that
these odderon contributions are very small and we show how a diquark clustering
in the proton can explain this effect. A good probe for the odderon exchange is
the photo- and electroproduction of pseudo-scalar mesons. We concentrate on the
pi^0 and show that the quasi elastic pi^0-production is again strongly
suppressed for a diquark structure of the proton whereas the cross sections for
diffractive proton dissociation are larger by orders of magnitude and rather
independent of the proton structure.Comment: 18 pages, LaTex2e, graphicx package, 14 eps figures include
Odderon and photon exchange in electroproduction of pseudoscalar mesons
We investigate the reaction where PS denotes a pseudoscalar
meson , or and X either a proton or resonance or
continuum states into which the proton can go by diffractive excitation. At
high energies photon and odderon exchange contribute to the reaction. The
photon exchange contribution is evaluated exactly using data for the total
virtual photon-proton absorption cross section. The odderon exchange
contribution is calculated in nonperturbative QCD, using functional integral
techniques and the model of the stochastic vacuum. For the proton we assume a
quark-diquark structure as suggested by the small odderon amplitude in and
forward scattering. We show that odderon exchange leads to a much
larger inelastic than elastic PS production cross section. Observation of our
reaction at HERA would establish the soft odderon as an exchange object on an
equal footing with the soft pomeron and would give us valuable insight into
both the nucleon structure and the mechanism of high energy diffractive
scattering.Comment: 20 pages, 7 figure
Chiral Symmetry and Diffractive Neutral Pion Photo- and Electroproduction
We show that diffractive production of a single neutral pion in
photon-induced reactions at high energy is dynamically suppressed due to the
approximate chiral symmetry of QCD. These reactions have been proposed as a
test of the odderon exchange mechanism. We show that the odderon contribution
to the amplitude for such reactions vanishes exactly in the chiral limit. This
result is obtained in a nonperturbative framework and by using PCAC relations
between the amplitudes for neutral pion and axial vector current production.Comment: 22 pages, 7 figure
Penicillin allergy SHACK : Survey of hospital and community knowledge
Aim
Penicillin allergy accounts for the majority of all reported adverse drug reactions in adults and children. Foregoing first-line antibiotic therapy due to penicillin allergy label is associated with an increased prevalence of infections by resistant organisms and longer hospitalisation. Clinician awareness of allergy assessment, referral indications, management of allergy and anaphylaxis is therefore vital but globally lacking. We aim to assess the knowledge of penicillin allergy, assessment and management in Western Australian health professionals.
Methods
An anonymous survey was distributed to pharmacists, nurses and physicians within Western Australian paediatric and adult Hospitals, Community and General Practice.
Results
In total, 487/611 were completed and included in the statistical analysis. Only 62% (301/487) of respondents routinely assessed for patient medication allergies. Of those who assessed allergy, 9% (28/301) of respondents met the Australian standards for allergy assessment. Only 22% (106/487) of participants correctly cited all indications for management with adrenaline in anaphylaxis to antibiotics and 67% (197/292) of physicians rarely or never referred to an allergy service. Paediatric clinicians had an increased understanding of allergy assessment and anaphylaxis management. Recent penicillin allergy education within a 5-year period led to significant improvements in allergy knowledge.
Conclusion
Overall, knowledge, assessment and management of penicillin allergies among practitioners in Western Australia are currently inadequate in adults and paediatric clinicians to provide safe and effective clinical care. The implementation of a targeted education program for WA health professionals is urgently required and is expected to improve clinician knowledge and aid standardised penicillin assessment (de-labelling) practices
Decomposition of the QCD String into Dipoles and Unintegrated Gluon Distributions
We present the perturbative and non-perturbative QCD structure of the
dipole-dipole scattering amplitude in momentum space. The perturbative
contribution is described by two-gluon exchange and the non-perturbative
contribution by the stochastic vacuum model which leads to confinement of the
quark and antiquark in the dipole via a string of color fields. This QCD string
gives important non-perturbative contributions to high-energy reactions. A new
structure different from the perturbative dipole factors is found in the
string-string scattering amplitude. The string can be represented as an
integral over stringless dipoles with a given dipole number density. This
decomposition of the QCD string into dipoles allows us to calculate the
unintegrated gluon distribution of hadrons and photons from the dipole-hadron
and dipole-photon cross section via kT-factorization.Comment: 43 pages, 14 figure
Two Photon Reactions at High Energies
Cross sections for the reactions gamma^(*) gamma^(*) --> hadrons and
gamma^(*) gamma^(*) --> 2 vector mesons are calculated as functions of energy
(sqrt(s) > 20 GeV) and photon virtualities. Good agreement with experiment is
obtained for the total hadronic cross section and, after allowing for a
valence-quark contribution from the hadronic part of the photon, with the
photon structure function at small x. The cross section for vector meson
production are shown to be experimentally accessible for moderate values of
Q^2. This is sufficient to probe the nature of the hard pomeron which has
recently been proposed.Comment: some changes in style, physics unchanged, final version to appear in
Phys.Rev.D, LaTeX2e, graphicx package, 15 eps-figures, 15p
Diffractive color-dipole nucleon scattering
We determine the diffractive scattering amplitude of a color-dipole on a
nucleon using a non-perturbative model of QCD which contains only parameters
taken from low-energy physics. This allows to relate specific features of the
confinement mechanisms with diffractive electro-production processes and
structure functions. The agreement with phenomenological data is satisfactory.Comment: 7 pages, 5 eps-figures, uses eps
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