1,464 research outputs found
Role of a_1(1260) resonance in multipion decays of light vector mesons
The contribution of the a_1(1260) meson to the amplitudes of the decays
rho(770) to 4 pi, omega(782) to 5 pi, and phi(1020) to 5 pi is analyzed in the
chiral model of pseudoscalar, vector, and axial vector mesons based on the
generalized hidden local symmetry added with the anomalous terms. The analysis
shows that inclusion of a_1 meson in the intermediate states results in
enhancement of the branching ratios of the above decays by the factor ranging
from 1.3 to 1.9 depending on the mass of a_1 meson ranging from 1.23 GeV to
m_{a_1}=m_rho sqrt{2}=1.09 GeV, the greater factor standing in case of lower
mass of the a_1.Comment: 14 pages, 5 figure
Basic concepts for convection parameterization in weather forecast and climate models: COST Action ES0905 final report
The research network “Basic Concepts for Convection Parameterization in Weather Forecast and Climate Models” was organized with European funding (COST Action ES0905) for the period of 2010–2014. Its extensive brainstorming suggests how the subgrid-scale parameterization problem in atmospheric modeling, especially for convection, can be examined and developed from the point of view of a robust theoretical basis. Our main cautions are current emphasis on massive observational data analyses and process studies. The closure and the entrainment–detrainment problems are identified as the two highest priorities for convection parameterization under the mass–flux formulation. The need for a drastic change of the current European research culture as concerns policies and funding in order not to further deplete the visions of the European researchers focusing on those basic issues is emphasized
Effective chiral Lagrangians for spin-1 mesons
The commonly used types of effective theory for vector mesons are reviewed
and their relationships clarified. They are shown to correspond to different
choices of field for spin-1 particles and the rules for transforming between
them are described. The importance of respecting chiral symmetry is stressed.
The choice of fields that transform homogeneously under the nonlinear
realisation of chiral symmetry imposes no preconceptions about the types of
coupling for the mesons. This representation thus provides a convenient
framework for relating different theories. It is also used to elucidate the
nature of the assumptions in specific hidden-gauge and massive Yang-Mills
models that have been widely used.Comment: 46 pages (RevTeX
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Working group 3: What are and how do we measure the pros and cons of existing approaches?
WG3 discussed both the pros and cons of existing schemes as well as metrics to measure relative advantages and disadvantages. We first provide a list of the current operational techniques and their respective advantages and disadvantages that were discussed in the WG. We do not claim
that the list is complete, and we note that the pros and cons are neither exhaustive nor quantitative. Nevertheless, it may be useful to note the WG’s consensus on the general
advantages and disadvantages of the most commonly-used schemes. We then list our recommendations for evaluating model uncertainty schemes. At the end is a short list pertaining to recommendations for further development of methods to represent model uncertainty
Many pion decays of rho(770) and omega(782) mesons in chiral theory
The decays rho(770) to 4 pi and omega(782) to 5pi are considered in detail in
the approach based on the Weinberg Lagrangian obtained upon the nonlinear
realization of chiral symmetry, added with the term induced by the anomalous
Lagrangian of Wess and Zumino. The partial widths and excitation curves of the
decays rho^0 to 2 pi^+ 2 pi^-, pi^+ pi^- 2 pi^0, rho^{+-} to 2 pi^{+-} pi^{-+}
pi^0, rho^(+-} to pi^(+-} 3 pi^0 are evaluated for e^+e^- annihilation,
photoproduction and tau lepton decays. The results of calculations are compared
with the recent CMD-2 data on the decay rho^0 to 2 pi^+ 2 pi^- observed in
e^+e^- annihilation. The omega to 5 pi decay widths and excitation curves in
e^+e^- annihilation are obtained. The angular distributions for various
combinations of the final pions in the decays rho to 4 pi and omega to 5 pi are
written. The perspectives of the experimental study of the above decays in
e^+e^- annihilation, tau lepton decays and photoproduction are discussed.Comment: Revtex, 32 pages including 11 ps figures. Replaced to fit the version
published in Phys. Rev. D. Material rearranged, clarifying remarks and
references added, typos fixe
Investigating the role of the HLA-Cw*06 and HLA-DRB1 genes in susceptibility to psoriatic arthritis: comparison with psoriasis and undifferentiated inflammatory arthritis
Annexin A2 Binds RNA and Reduces the Frameshifting Efficiency of Infectious Bronchitis Virus
Annexin A2 (ANXA2) is a protein implicated in diverse cellular functions, including exocytosis, DNA synthesis and cell proliferation. It was recently proposed to be involved in RNA metabolism because it was shown to associate with some cellular mRNA. Here, we identified ANXA2 as a RNA binding protein (RBP) that binds IBV (Infectious Bronchitis Virus) pseudoknot RNA. We first confirmed the binding of ANXA2 to IBV pseudoknot RNA by ultraviolet crosslinking and showed its binding to RNA pseudoknot with ANXA2 protein in vitro and in the cells. Since the RNA pseudoknot located in the frameshifting region of IBV was used as bait for cellular RBPs, we tested whether ANXA2 could regulate the frameshfting of IBV pseudoknot RNA by dual luciferase assay. Overexpression of ANXA2 significantly reduced the frameshifting efficiency from IBV pseudoknot RNA and knockdown of the protein strikingly increased the frameshifting efficiency. The results suggest that ANXA2 is a cellular RBP that can modulate the frameshifting efficiency of viral RNA, enabling it to act as an anti-viral cellular protein, and hinting at roles in RNA metabolism for other cellular mRNAs
Exposure and impact of a mass media campaign targeting sexual health amongst Scottish men who have sex with men: an outcome evaluation
Background:
This paper explores the exposure and impact of a Scottish mass media campaign: Make Your Position Clear. It ran from October 2009 to July 2010, targeted gay men and other men who have sex with men (MSM), and had two key aims: to promote regular sexual health and HIV testing every 6Â months, and to promote the use of appropriate condoms and water-based lubricant with each episode of anal intercourse.
Methods: A cross-sectional survey (anonymous and self-report) was conducted 10Â months after the campaign was launched (July 2010). Men were recruited from commercial venues. Outcome measures included use of lubricant, testing for sexually transmitted infections and HIV, and intentions to seek HIV testing within the following six months. Linear-by-linear chi-square analysis and binary logistic regressions were conducted to explore the associations between the outcome measures and campaign exposure.
Results:
The total sample was 822 men (62.6% response rate). Men self-identifying as HIV positive were excluded from the analysis (n = 38). Binary logistic analysis indicated that those with mid or high campaign exposure were more likely to have been tested for HIV in the previous six months when adjusted for age, area of residence and use of the “gay scene” (AOR = 1.96, 95% CI = 1.26 to 3.06, p = .003), but were not more likely to be tested for STIs (AOR = 1.37, 95% CI = 0.88 to 2.16, p = .167). When adjusted for previous HIV testing, those with mid or high campaign exposure were not more likely to indicate intention to be tested for HIV in the following six months (AOR = 1.30, 95% CI = 0.73 to 2.32, p = .367). Those with no campaign exposure were less likely than those with low exposure to have used appropriate lubricant with anal sex partners in the previous year (AOR = 0.42, 95% CI = 0.23 to 0.77, p = .005).
Conclusions:
The campaign had demonstrable reach. The analysis showed partial support for the role of mass media campaigns in improving sexual health outcomes. This suggests that a role for mass media campaigns remains within combination HIV prevention
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