103 research outputs found
Weakly-induced strong CP-violation
Weak interaction contributions to the strong theta parameter are revisited in
the frame of a large-Nc Chiral Perturbation Theory. Focusing on the hadronic
(eta,etaprime) \to pi pi amplitudes, we express these second-order corrections
in terms of the CP-violating parameter in K \to pi pi decays to obtain
Delta_w(theta) approx 10^{-17} at O(GF^2 epsilonprime).Comment: 11 pages, 1 figure. One reference and comments on electroweak
corrections added. Version published in Physics Letters
An upper bound on the Kaon B-parameter and Re(epsilon_K)
New precise data in B physics and theoretical developments in K physics lead
us to reconsider the weak K^0-\bar{K}^0 transition from a large-N_c viewpoint,
N_c being the number of colors. In this framework, we infer an upper limit on
\hat{B}_K and the Kaon indirect CP violation.Comment: 11 pages, 4 figures. V2 : Minor corrections, final version accepted
for publication in JHE
Biodiversity assessment in LCA: a validation at field and farm scale in eight European regions
Kaon mixing and the charm mass
We study contributions to the Delta S=2 weak Chiral Lagrangian producing
K0-K0bar mixing which are not enhanced by the charm mass. For the real part,
these contributions turn out to be related to the box diagram with up quarks
but, unlike in perturbation theory, they do not vanish in the limit m_u->0.
They increase the leading contribution to the K_L-K_S mass difference by ~10%.
This means that short distances amount to (90+-15)% of this mass difference.
For the imaginary part, we find a correction to the lambda_c^2 m_c^2 term of
-5% from the integration of charm, which is a small contribution to epsilon_K.
The calculation is done in the large-Nc limit and we show explicitly how to
match short and long distances.Comment: 20 pages, 5 figures. Typos fixe
Supersymmetric Dark Matter
There is almost universal agreement among astronomers that most of the mass
in the Universe and most of the mass in the Galactic halo is dark. Many lines
of reasoning suggest that the dark matter consists of some new, as yet
undiscovered, weakly-interacting massive particle (WIMP). There is now a vast
experimental effort being surmounted to detect WIMPS in the halo. The most
promising techniques involve direct detection in low-background laboratory
detectors and indirect detection through observation of energetic neutrinos
from annihilation of WIMPs that have accumulated in the Sun and/or the Earth.
Of the many WIMP candidates, perhaps the best motivated and certainly the most
theoretically developed is the neutralino, the lightest superpartner in many
supersymmetric theories. We review the minimal supersymmetric extension of the
Standard Model and discuss prospects for detection of neutralino dark matter.
We review in detail how to calculate the cosmological abundance of the
neutralino and the event rates for both direct- and indirect-detection schemes,
and we discuss astrophysical and laboratory constraints on supersymmetric
models. We isolate and clarify the uncertainties from particle physics, nuclear
physics, and astrophysics that enter at each step in the calculation. We
briefly review other related dark-matter candidates and detection techniques.Comment: The complete postscript file is available at
ftp://ftp.npac.syr.edu/pub/users/jungman/susyreview/susyreview.ps.Z The TeX
source and figures (plain TeX; macros included) are at
ftp://ftp.npac.syr.edu/pub/users/jungman/susyreview/susyreview.tar.Z Full
paper NOT submitted to lanl archive: table of contents only. To appear in
Physics Report
LongITools:Dynamic longitudinal exposome trajectories in cardiovascular and metabolic noncommunicable diseases
The current epidemics of cardiovascular and metabolic noncommunicable diseases have emerged alongside dramatic modifications in lifestyle and living environments. These correspond to changes in our "modern" postwar societies globally characterized by rural-to-urban migration, modernization of agricultural practices, and transportation, climate change, and aging. Evidence suggests that these changes are related to each other, although the social and biological mechanisms as well as their interactions have yet to be uncovered. LongITools, as one of the 9 projects included in the European Human Exposome Network, will tackle this environmental health equation linking multidimensional environmental exposures to the occurrence of cardiovascular and metabolic noncommunicable diseases
Development of Core Outcome Measures sets for paediatric and adult Severe Asthma (COMSA)
BACKGROUND: Effectiveness studies with biological therapies for asthma lack standardised outcome measures. The COMSA (Core Outcome Measures sets for paediatric and adult Severe Asthma) working group sought to develop Core Outcome Measures (COM) sets to facilitate better synthesis of data and appraisal of biologics in paediatric and adult asthma clinical studies.METHODS: COMSA utilised a multi-stakeholder consensus process among patients with severe asthma, adult, and paediatric clinicians, pharmaceutical representatives and health regulators from across Europe. Evidence included a systematic review of development, validity, and reliability of selected outcome measures plus a narrative review and a pan-European survey to better understand patients' and carers' views about outcome measures. It was discussed using a modified GRADE Evidence to Decision framework. Anonymous voting was conducted using predefined consensus criteria.RESULTS: Both adult and paediatric COM sets include forced expiratory volume in 1 s (FEV1) as z scores, annual frequency of severe exacerbations and maintenance oral corticosteroid use. Additionally, the paediatric COM set includes the Paediatric Asthma Quality of Life Questionnaire, and Asthma Control Test (ACT) or Childhood-ACT while the adult COM includes the Severe Asthma Questionnaire and the Asthma Control Questionnaire-6 (symptoms and rescue medication use reported separately).CONCLUSIONS: This patient-centred collaboration has produced two COM sets for paediatric and adult severe asthma. It is expected that they will inform the methodology of future clinical trials, enhance comparability of efficacy and effectiveness of biological therapies, and help assess their socioeconomic value. COMSA will inform definitions of non-response and response to biological therapy for severe asthma.</p
Coupled transcriptome and proteome analysis of human lymphotropic tumor viruses: insights on the detection and discovery of viral genes
<p>Abstract</p> <p>Background</p> <p>Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) are related human tumor viruses that cause primary effusion lymphomas (PEL) and Burkitt's lymphomas (BL), respectively. Viral genes expressed in naturally-infected cancer cells contribute to disease pathogenesis; knowing which viral genes are expressed is critical in understanding how these viruses cause cancer. To evaluate the expression of viral genes, we used high-resolution separation and mass spectrometry coupled with custom tiling arrays to align the viral proteomes and transcriptomes of three PEL and two BL cell lines under latent and lytic culture conditions.</p> <p>Results</p> <p>The majority of viral genes were efficiently detected at the transcript and/or protein level on manipulating the viral life cycle. Overall the correlation of expressed viral proteins and transcripts was highly complementary in both validating and providing orthogonal data with latent/lytic viral gene expression. Our approach also identified novel viral genes in both KSHV and EBV, and extends viral genome annotation. Several previously uncharacterized genes were validated at both transcript and protein levels.</p> <p>Conclusions</p> <p>This systems biology approach coupling proteome and transcriptome measurements provides a comprehensive view of viral gene expression that could not have been attained using each methodology independently. Detection of viral proteins in combination with viral transcripts is a potentially powerful method for establishing virus-disease relationships.</p
Implications of TeV Flavor Physics for the \Delta I =1/2 Rule and the B-meson Semileptonic Branching Ratio
Two of the outstanding discrepancies between weak interaction phenomenology
and the standard model come in the large size of the
enhancement in decays and in the small value of the semileptonic
branching ratio. We argue that these discrepancies are naturally explained by
chromomagnetic dipole operators arising from new physics at the TeV scale.
These operators are closely connected to diagrams which contribute to the quark
mass matrix, and we show how the proper enhancement of the hadronic decays of
and quarks can be linked to generation of particular
Cabbibo-Kobayaski-Maskawa mixing angles or quark masses. We confirm our
model-independent analysis with detailed consideration of supersymmetric models
and of technicolor models with techniscalars. This picture has additional
phenomenological predictions for the system: The branching ratio of
charmless nonleptonic decays should be of order 20\%, due to a large rate
for , while there are no dangerous new contributions to . Sizable contributions to are a common feature of
models incorporating this mechanism. In techniscalar models the
coupling is enhanced, in association with sizable contributions to .Comment: 52 pages+12 postscript figures, SLAC-PUB-662
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