3,456 research outputs found
Capture of Solar and Higher-Energy Neutrinos by Iodine 127
We discuss and improve a recent treatment of the absorption of solar
neutrinos by I, in connection with a proposed solar neutrino
detector. With standard-solar-model fluxes and an in-medium value of -1.0 for
the axial-vector coupling constant , we obtain a B-neutrino cross
section of 3.3, about 50\% larger than in our previous work,
and a Be cross section that is less certain but nevertheless also larger
than before. We then apply the improved techniques to higher incoming energies
that obtain at the LAMPF beam dump, where an experiment is underway to finalize
a calibration of the I with electron neutrinos from muon decay. We
find that forbidden operators, which play no role in solar-neutrino absorption,
contribute nonnegligibly to the LAMPF cross section, and that the preliminary
LAMPF mean value is significantly larger than our prediction.Comment: 13 pages + 3 postscript figures (attached), in RevTex 3 , submitted
to Phys. Rev.
Trends in Loss to Follow-Up among Migrant Workers on Antiretroviral Therapy in a Community Cohort in Lesotho
BACKGROUND: The provision of antiretroviral therapy (ART) to migrant populations raises particular challenges with respect to ensuring adequate treatment support, adherence, and retention in care. We assessed rates of loss to follow-up for migrant workers compared with non-migrant workers in a routine treatment programme in Morjia, Lesotho. DESIGN: All adult patients (â„18 years) initiating ART between January 1, 2008, and December 31, 2008, and followed up until the end of 2009, were included in the study. We described rates of loss to follow-up according to migrant status by Kaplan-Meier estimates, and used Poisson regression to model associations between migrant status and loss to follow-up controlling for potential confounders identified a priori. RESULTS: Our cohort comprised 1185 people, among whom 12% (148) were migrant workers. Among the migrant workers, median age was 36.1 (29.6-45.9) and the majority (55%) were male. We found no statistically significant differences between baseline characteristics and migrant status. Rates of lost to follow up were similar between migrants and non-migrants in the first 3 months but differences increased thereafter. Between 3 and 6 months after initiating antiretroviral therapy, migrants had a 2.78-fold increased rate of defaulting (95%CI 1.15-6.73); between 6 and 12 months the rate was 2.36 times greater (95%CI 1.18-4.73), whereas after 1 year the rate was 6.69 times greater (95%CI 3.18-14.09). CONCLUSIONS: Our study highlights the need for programme implementers to take into account the specific challenges that may influence continuity of antiretroviral treatment and care for migrant populations
News, intelligence and 'little lies' : rumours between the Cherokees and the British 1740-1785
Rumour and information are one of the most fundamental ways in which people engage
with one another. Rumours can change the way that individuals and groups see each other
and the actions that they take. Sociologists and anthropologists have long used rumour as a
way to explore the experiences of their subjects. Historians of early America have, in recent
years, begun to make use of rumour as a way of examining the, often hidden, world of
interactions between American Indians and white Europeans. This thesis will expand upon
this work by exploring the changing role of rumour within an intercultural relationship over
several decades. This thesis will focus on rumour in the relationship between the Cherokee
Nation and the colonists of the British Empire. It will explore the ways that rumour
influenced these interactions and the impact of the rapidly changing backcountry
environment of the latter eighteenth century, both on rumour and on the wider Cherokee-
British relationship. This thesis will argue that rumour shifted in the course of the
eighteenth century from being a diplomatic tool which could be used- either to create
further panic and confusion or to calm and smooth over problems- to an uncontrollable
force which would deepen and exacerbate the divisions between Cherokees and the
British. Rumour played an important role in politics and society in the eighteenth century
backcountry and its changing function offers a way to better understand the shifting
currents of life in early America
Tests of the Equivalence Principle with Neutral Kaons
We test the Principle of Equivalence for particles and antiparticles, using
CPLEAR data on tagged K0 and K0bar decays into pi^+ pi^-. For the first time,
we search for possible annual, monthly and diurnal modulations of the
observables |eta_{+-}| and phi_{+-}, that could be correlated with variations
in astrophysical potentials. Within the accuracy of CPLEAR, the measured values
of |eta_{+-}| and phi_{+-} are found not to be correlated with changes of the
gravitational potential. We analyze data assuming effective scalar, vector and
tensor interactions, and we conclude that the Principle of Equivalence between
particles and antiparticles holds to a level of 6.5, 4.3 and 1.8 x 10^{-9},
respectively, for scalar, vector and tensor potentials originating from the Sun
with a range much greater than the distance Earth-Sun. We also study
energy-dependent effects that might arise from vector or tensor interactions.
Finally, we compile upper limits on the gravitational coupling difference
between K0 and K0bar as a function of the scalar, vector and tensor interaction
range.Comment: 15 pages latex 2e, five figures, one style file (cernart.csl)
incorporate
The multiple facets of the Hsp90 machine
International audienceThe Ninth International Conference on the Hsp90 Chaperone Machine concluded in October 2018, in Leysin, Switzerland. The program highlighted findings in various areas, including integrated insight into molecular mechanism of Hsp90, cochaperones, and clientsâ structure and function.Heat shock protein-90 (Hsp90) is a molecular chaperone critical for the folding, stability, and activity of client proteins 1. Hsp90 and its orthologs, including bacterial HtpG, mitochondrial TRAP1 and endoplasmic reticulum Grp94, exist as dimers, hydrolyze ATP, and cycle between distinct conformational states. Hsp90 preferentially binds proteins in near native states facilitating their remodeling for protein interactions and signaling. At the 9th International Conference on the Hsp90 Chaperone Machine approximately one-third of the attendees shared their data on Hsp90 structure and function through short talks (Figure 1). Here, we distill and summarize their finding
Search for Branons at LEP
We search, in the context of extra-dimension scenarios, for the possible
existence of brane fluctuations, called branons. Events with a single photon or
a single Z-boson and missing energy and momentum collected with the L3 detector
in e^+ e^- collisions at centre-of-mass energies sqrt{s}=189-209$ GeV are
analysed. No excess over the Standard Model expectations is found and a lower
limit at 95% confidence level of 103 GeV is derived for the mass of branons,
for a scenario with small brane tensions. Alternatively, under the assumption
of a light branon, brane tensions below 180 GeV are excluded
Search for CP violation in decays
A model-independent search for direct CP violation in the Cabibbo suppressed
decay in a sample of approximately 370,000 decays is
carried out. The data were collected by the LHCb experiment in 2010 and
correspond to an integrated luminosity of 35 pb. The normalized Dalitz
plot distributions for and are compared using four different
binning schemes that are sensitive to different manifestations of CP violation.
No evidence for CP asymmetry is found.Comment: 13 pages, 8 figures, submitted to Phys. Rev.
Measurement of Exclusive rho^0 rho^0 Production in Two-Photon Collisions at High Q^2 at LEP
Exclusive rho rho production in two-photon collisions involving a single
highly virtual photon is studied with data collected at LEP at centre-of-mass
energies 89GeV < \sqrt{s} < 209GeV with a total integrated luminosity of
854.7pb^-1 The cross section of the process gamma gamma^* -> rho rho is
determined as a function of the photon virtuality, Q^2 and the two-photon
centre-of-mass energy, Wgg, in the kinematic region: 1.2GeV^2 < Q^2 < 30GeV^2
and 1.1GeV < Wgg < 3GeV
Formation of the in Two-Photon Collisions at LEP
The two-photon width of the meson has been
measured with the L3 detector at LEP. The is studied in the decay
modes , KK, KK,
KK, , , and
using an integrated luminosity of 140 pb at GeV and
of 52 pb at GeV. The result is
(BR) keV. The dependence of the cross section is studied for
GeV. It is found to be better described by a Vector Meson
Dominance model form factor with a J-pole than with a -pole. In addition,
a signal of events is observed at the mass. Upper limits
for the two-photon widths of the , , and are also
given
- âŠ