710 research outputs found

    Odderon and seven Pomerons: QCD Reggeon field theory from JIMWLK evolution

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    We reinterpret the JIMWLK/KLWMIJ evolution equation as the QCD Reggeon field theory (RFT). The basic "quantum Reggeon field" in this theory is the unitary matrix RR which represents the single gluon scattering matrix. We discuss the peculiarities of the Hilbert space on which the RFT Hamiltonian acts. We develop a perturbative expansion in the RFT framework, and find several eigenstates of the zeroth order Hamiltonian. The zeroth order of this perturbation preserves the number of ss - channel gluons. The eigenstates have a natural interpretation in terms of the tt - channel exchanges. Studying the single ss - channel gluon sector we find the eigenstates which include the reggeized gluon and five other colored Reggeons. In the two (ss - channel) gluon sector we study only singlet color exchanges. We find five charge conjugation even states. The bound state of two reggeized gluons is the standard BFKL Pomeron. The intercepts of the other Pomerons in the large NN limit are 1+ωP=1+2ω1+\omega_P=1+2\omega where 1+ω1+\omega is the intercept of the BFKL Pomeron, but their coupling in perturbation theory is suppressed by at least 1/N21/N^2 relative to the double BFKL Pomeron exchange. For the [27,27][27,27] Pomeron we find ω[27,27]=2ω+O(1/N)>2ω\omega_{[27,27]}=2\omega+O(1/N)>2\omega. We also find three charge conjugation odd exchanges, one of which is the unit intercept Bartels-Lipatov-Vacca Odderon, while another one has an interecept greater than unity. We explain in what sense our calculation goes beyond the standard BFKL/BKP calculation. We make additional comments and discuss open questions in our approach.Comment: 58 pages, 4 figures, Extended version. To appear in JHE

    Charm Contribution to the Structure Function in Diffractive Deep Inelastic Scattering

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    The charm contribution to the structure functions of diffractive deep inelastic scattering is considered here within the context of the Ingelman-Schlein model. Numerical estimations of this contribution are made from parametrizations of the HERA data. Influence of the Pomeron flux factor is analized as well as the effect of the shape of the initial parton distribution employed in the calculations. The obtained results indicate that the charm contribution to diffractive deep inelastic process might be large enough to be measured in the HERA experiments.Comment: 16 pages, RevTeX, 6 figures, to be published in Physical Review

    The Swiss Multiple Sclerosis Cohort-Study (SMSC): A Prospective Swiss Wide Investigation of Key Phases in Disease Evolution and New Treatment Options.

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    The mechanisms leading to disability and the long-term efficacy and safety of disease modifying drugs (DMDs) in multiple sclerosis (MS) are unclear. We aimed at building a prospective cohort of MS patients with standardized collection of demographic, clinical, MRI data and body fluids that can be used to develop prognostic indicators and biomarkers of disease evolution and therapeutic response. The Swiss MS Cohort (SMSC) is a prospective observational study performed across seven Swiss MS centers including patients with MS, clinically isolated syndrome (CIS), radiologically isolated syndrome or neuromyelitis optica. Neurological and radiological assessments and biological samples are collected every 6-12 months. We recruited 872 patients (clinically isolated syndrome [CIS] 5.5%, relapsing-remitting MS [RRMS] 85.8%, primary progressive MS [PPMS] 3.5%, secondary progressive MS [SPMS] 5.2%) between June 2012 and July 2015. We performed 2,286 visits (median follow-up 398 days) and collected 2,274 serum, plasma and blood samples, 152 cerebrospinal fluid samples and 1,276 brain MRI scans. 158 relapses occurred and expanded disability status scale (EDSS) scores increased in PPMS, SPMS and RRMS patients experiencing relapses. Most RRMS patients were treated with fingolimod (33.4%), natalizumab (24.5%) or injectable DMDs (13.6%). The SMSC will provide relevant information regarding DMDs efficacy and safety and will serve as a comprehensive infrastructure available for nested research projects

    Engineering, expression in transgenic plants and characterisation of e559, a rabies virus-neutralising monoclonal antibody.

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    Rabies post-exposure prophylaxis (PEP) currently comprises administration of rabies vaccine together with rabies immunoglobulin (RIG) of either equine or human origin. In the developing world, RIG preparations are expensive, often in short supply, and of variable efficacy. Therefore, we are seeking to develop a monoclonal antibody cocktail to replace RIG. Here, we describe the cloning, engineering and production in plants of a candidate monoclonal antibody (E559) for inclusion in such a cocktail. The murine constant domains of E559 were replaced with human IgG1κ constant domains and the resulting chimeric mouse-human genes were cloned into plant expression vectors for stable nuclear transformation of Nicotiana tabacum. The plant-expressed, chimeric antibody was purified and biochemically characterized, was demonstrated to neutralize rabies virus in a fluorescent antibody virus neutralization assay, and conferred protection in a hamster challenge model

    Kwantitatiewe Radio-isotoop Kardiografie met die Sintillasie-kamera

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    Methods for obtainiR9 various cardiac parameters, using radio-isotopes and the scintillation camera, have improved tremendously during recent· years. These investigations offer a simplified screening test for visual interpretation. By the use of numerical techniques, quantitative information can be obtained, making investigations more sensitive. Left-to-right shunts, cardiac output, left ventricular ejection fraction and other parameters can be quantitated

    Intraregional variability in chironomid-inferred temperature estimates and the influence of river inundations on lacustrine chironomid assemblages.

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    Floodplain lakes are rarely analysed for fossil chironomids and usually not incorporated in modern chironomid-climate calibration datasets because of the potential complex hydrological processes that could result from flooding of the lakes. In order to investigate this potential influence of river inundations on fossil chironomid assemblages, 13 regularly inundated lakes and 20 lakes isolated from riverine influence were sampled and their surface sediments analysed for subfossil chironomid assemblages. The physical and chemical settings of all lakes were similar, although the variation in the environmental variables was higher in the lakes isolated from riverine influence. Chironomid concentration and taxon richness show significant differences between the two classes of lakes, and the variation in these variables is best explained by loss-on-ignition of the sediments (LOI). Relative chironomid abundances show some differences between the two groups of lakes, with several chironomid taxa occurring preferentially in one of the two lake-types. The variability in chironomid assemblages is also best explained by LOI. Application of a chironomid-temperature inference model shows that both types of lakes reconstruct July air temperatures that are equal to, or slightly underestimating, the measured temperature of the region. We conclude that, although there are some differences between the chironomid assemblages of floodplain lakes and of isolated lakes, these differences do not have a major effect on chironomid-based temperature reconstruction. © 2007 Springer Science+Business Media B.V

    Serological prevalence of leptospiral antibodies in pigs in South Africa

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    A serological survey for leptospiral antibodies was carried out on 5 041 abattoir pigs from different regions in South Africa. Antibodies to at least one serovar were detected in 22,2% of the animals. The serovars showing the highest prevalence were: icterohaemorrhagiae (12,6%), hardjo (12,1 %) and bratislava (7,5%). The serum dilution level at which 90% of the sera reacted was 1/80 or 1/160.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

    Azimuthal Distribution of Quark-Antiquark Jets in DIS Diffractive Dissociation

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    We investigate the azimuthal distribution of quark-antiquark jets in DIS diffractive dissociation with large transverse momentum. In this kinematical region the matrix element is expressed in terms of the gluon structure function. For the transverse part of the cross section we find a cos(2ϕ)\cos(2 \phi)-distribution with the maximum at ϕ=±π/2\phi = \pm \pi/2, i.e.\ the jets prefer a direction perpendicular to the electron plane. This is in contrast to boson gluon fusion where the qqˉq\bar{q} jet cross section for transversely polarized bosons peaks at ϕ=0\phi=0 and ϕ=π\phi=\pi. We discuss the origin of this striking difference and present numerical results relevant for the diffractive dissociation at HERA.Comment: 12 pages, latex, 7 figure
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