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Treatment Interruption after Pregnancy: Effects on Disease Progression and Laboratory Findings
Objective. To assess clinical progression and inflammatory markers among women stopping or continuing antiretroviral therapy (ART) after pregnancy. Methods. ART-naïve women with CD4+ lymphocyte counts >350 cells/uL initiating ART during pregnancy had clinical events and laboratory markers compared over one year postpartum between those stopping (n = 59) or continuing (n = 147) ART. Results. Slopes in CD4 count and HIV RNA did not differ between groups overall and in subsets of ZDV or combination therapy. The hazard ratio (HR) of a new class B event was 2.09 (95% CI 0.79–5.58) among women stopping ART, 1.24 (0.31–4.95) in those stopping ZDV, and 2.93 (0.64–13.36) among those stopping combination therapy. Women stopping ART had increased immune activation. No significant differences were seen in C-reactive protein, lipids, leptin, or interleukin-6. Conclusions. While changes in CD4 and HIV RNA levels over one year were similar between women stopping or continuing ART postpartum, higher immune activation among women stopping therapy requires further study
Treatment Interruption after Pregnancy: Effects on Disease Progression and Laboratory Findings
Objective. To assess clinical progression and inflammatory markers among women stopping or continuing antiretroviral therapy (ART) after pregnancy.
Methods. ART-naïve women with CD4+ lymphocyte counts >350 cells/uL initiating ART during pregnancy had clinical events and laboratory markers compared over one year postpartum between those stopping (n = 59) or continuing (n = 147) ART. Results. Slopes in CD4 count and HIV RNA did not differ between groups overall and in subsets of ZDV or combination therapy. The hazard ratio (HR) of a new class B event was 2.09 (95% CI 0.79–5.58) among women stopping ART, 1.24 (0.31–4.95) in those stopping ZDV, and 2.93 (0.64–13.36) among those stopping combination therapy. Women stopping ART had increased immune activation. No significant differences were seen in C-reactive protein, lipids, leptin, or interleukin-6. Conclusions. While changes in CD4 and HIV RNA levels over one year were similar between women stopping or continuing ART postpartum, higher immune activation among women stopping therapy requires further study
Banks' risk assessment of Swedish SMEs
Building on the literatures on asymmetric information and risk taking, this paper applies conjoint experiments to investigate lending officers' probabilities of supporting credit to established or existing SMEs. Using a sample of 114 Swedish lending officers, we test hypotheses concerning how information on the borrower's ability to repay the loan; alignment of risk preferences; and risk sharing affect their willingness to grant credit. Results suggest that features that reduce the risk to the bank and shift the risk to the borrower have the largest impact. The paper highlights the interaction between factors that influence the credit decision. Implications for SMEs, banks and research are discussed
Measurements of differential cross sections of Z/gamma*+jets+X events in proton anti-proton collisions at sqrt{s}=1.96 TeV
We present cross section measurements for Z/gamma*+jets+X production,
differential in the transverse momenta of the three leading jets. The data
sample was collected with the D0 detector at the Fermilab Tevatron proton
anti-proton collider at a center-of-mass energy of 1.96 TeV and corresponds to
an integrated luminosity of 1 fb-1. Leading and next-to-leading order
perturbative QCD predictions are compared with the measurements, and agreement
is found within the theoretical and experimental uncertainties. We also make
comparisons with the predictions of four event generators. Two
parton-shower-based generators show significant shape and normalization
differences with respect to the data. In contrast, two generators combining
tree-level matrix elements with a parton shower give a reasonable description
of the the shapes observed in data, but the predicted normalizations show
significant differences with respect to the data, reflecting large scale
uncertainties. For specific choices of scales, the normalizations for either
generator can be made to agree with the measurements.Comment: Published in PLB. 11 pages, 3 figure
Search for resonant diphoton production with the D0 detector
We present a search for a narrow resonance in the inclusive diphoton final
state using 2.7 fb-1 of data collected with the D0 detector at the Fermilab
Tevatron ppbar Collider. We observe good agreement between the data and the
background prediction, and set the first 95% C.L. upper limits on the
production cross section times the branching ratio for decay into a pair of
photons for resonance masses between 100 and 150 GeV. This search is also
interpreted in the context of several models of electroweak symmetry breaking
with a Higgs boson decaying into two photons.Comment: 7 pages, 3 figures
Search for charged Higgs bosons decaying to top and bottom quarks in ppbar collisions
We describe a search for production of a charged Higgs boson, q \bar{q'} ->
H^+, reconstructed in the t\bar{b} final state in the mass range 180 <= M_{H^+}
<= 300 GeV. The search was undertaken at the Fermilab Tevatron collider with a
center-of-mass energy sqrt{s} = 1.96 TeV and uses 0.9 fb^{-1} of data collected
with the D0 detector. We find no evidence for charged Higgs boson production
and set upper limits on the production cross section in the Types I, II and III
two-Higgs-doublet models (2HDMs). An excluded region in the (M_{H^+},tan\beta)
plane for Type I 2HDM is presented.Comment: Submitted to Phys. Rev. Letter
Measurement of the t-channel single top quark production cross section
The D0 collaboration reports direct evidence for electroweak production of
single top quarks through the t-channel exchange of a virtual W boson. This is
the first analysis to isolate an individual single top quark production
channel. We select events containing an isolated electron or muon, missing
transverse energy, and two, three or four jets from 2.3 fb^-1 of ppbar
collisions at the Fermilab Tevatron Collider. One or two of the jets are
identified as containing a b hadron. We combine three multivariate techniques
optimized for the t-channel process to measure the t- and s-channel cross
sections simultaneously. We measure cross sections of 3.14 +0.94 -0.80 pb for
the t-channel and 1.05 +-0.81 pb for the s-channel. The measured t-channel
result is found to have a significance of 4.8 standard deviations and is
consistent with the standard model prediction.Comment: 7 pages, 6 figure
Search for scalar leptoquarks and T-odd quarks in the acoplanar jet topology using 2.5 fb-1 of ppbar collision data at sqrt(s)=1.96 TeV
A search for new physics in the acoplanar jet topology has been performed in
2.5 fb-1 of data from ppbar collisions at sqrt(s)=1.96 TeV, recorded by the D0
detector at the Fermilab Tevatron Collider. The numbers of events with exactly
two acoplanar jets and missing transverse energy are in good agreement with the
standard model expectations. The result of this search has been used to set a
lower mass limit of 205 GeV at the 95% C.L. on the mass of a scalar leptoquark
when this particle decays exclusively into a quark and a neutrino. In the
framework of the Little Higgs model with T-parity, limits have also been
obtained on the T-odd quark mass as a function of the T-odd photon mass
Observation of ZZ production in ppbar collisions at sqrt(s) = 1.96 TeV
We present an observation for ZZ -> l+l-l'+l'- (l, l' = e or mu) production
in ppbar collisions at a center-of-mass energy of sqrt(s) = 1.96 TeV. Using 1.7
fb-1 of data collected by the D0 experiment at the Fermilab Tevatron Collider,
we observe three candidate events with an expected background of 0.14 +0.03
-0.02 events. The significance of this observation is 5.3 standard deviations.
The combination of D0 results in this channel, as well as in ZZ -> l+l-nunubar,
yields a significance of 5.7 standard deviations and a combined cross section
of sigma(ZZ) = 1.60 +/- 0.63 (stat.) +0.16 -0.17 (syst.) pb.Comment: 7 pages, 1 figure, 2 tables Modified slightly following review
proces
A search for the standard model Higgs boson in the missing energy and acoplanar b-jet topology at sqrt(s) = 1.96 TeV
We report a search for the standard model Higgs boson in the missing energy
and acoplanar b-jet topology, using an integrated luminosity of 0.93 inverse
femtobarn recorded by the D0 detector at the Fermilab Tevatron Collider. The
analysis includes signal contributions from pp->ZH->nu nu b b, as well as from
WH production in which the charged lepton from the W boson decay is undetected.
Neural networks are used to separate signal from background. In the absence of
a signal, we set limits on the cross section of pp->VH times the branching
ratio of H->bb at the 95% C.L. of 2.6 - 2.3 pb, for Higgs boson masses in the
range 105 - 135 GeV, where V=W,Z. The corresponding expected limits range from
2.8 pb - 2.0 pb.Comment: Submitted to Phys. Rev. Letter
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