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Association of Cytomegalovirus DNA and Immunologic Markers of Cardiovascular Disease.
BackgroundPersons living with human immunodeficiency virus (HIV) (PLWH) with high cytomegalovirus (CMV)-specific interferon (IFN) γ response have increased numbers of endothelium homing receptor (CX3CR1)+-expressing cells that are associated with cardiovascular disease. The current study was performed to investigate the effect of cellular levels of CMV DNA on these markers.MethodsEighty paired peripheral blood mononuclear cell samples were collected ≥12 months apart from 40 CMV-seropositive PLWH with suppressed HIV RNA, who started antiretroviral therapy at median of 3-months of infection. The samples were assessed for CMV-specific IFN-γ response by means of enzyme-linked immunospot assay, and participants were classified as low responders (LRs) or high responders (HRs) based on IFN-γ production (≤100 or >100 spot-forming units [SFUs]/105 cells).ResultsOf the 40 participants, 26 (65%) were HRs and 14 (35%) LRs at baseline, which did not change over time or by CMV levels (median at first/second time points, 383/308 SFUs/106 cells for HRs vs 21/41 SFUs/106 for LRs). A decrease in IFN-γ over time was associated with higher CMV DNA levels (P < .01). High CMV response was also associated with increased CD28+CD27-CD4+ T cells expressing CX3CR1 (P < .001). Similarly, increased IFN-γ production was associated with increased CMV-specific CX3CR1+CD28+CD27-CD4+ and CD8+ T cells (P < .001).ConclusionsThese findings demonstrate that levels of CMV-specific IFN-γ response in PLWH are stable over time, and that HRs have increased circulating T cells expressing CX3CR1 that may put them at increased risk of cardiovascular disease and other inflammatory diseases
XMM-Newton Observation of the Northwest Radio Relic Region in Abell 3667
Abell 3667 is the archetype of a merging cluster with radio relics. The NW
radio relic is the brightest cluster relic or halo known, and is believed to be
due to a strong merger shock. We have observed the NW relic for 40 ksec of net
XMM time. We observe a global decline of temperature across the relic from 6 to
1 keV, similar to the Suzaku results. Our new observations reveal a sharp
change of both temperature and surface brightness near the position of the
relic. The increased X-ray emission on the relic can be equivalently well
described by either a thermal or nonthermal spectral model. The parameters of
the thermal model are consistent with a Mach number M~2 shock and a shock speed
of ~1200 km s^-1. The energy content of the relativistic particles in the radio
relic can be explained if they are (re)-accelerated by the shock with an
efficiency of ~0.2%. Comparing the limit on the inverse Compton X-ray emission
with the measured radio synchrotron emission, we set a lower limit to the
magnetic field in the relic of 3 muG. If the emission from the relic is
non-thermal, this lower limit is in fact the required magnetic field.Comment: 11 pages, ApJ in pres
Light Bullet Modes in Self-Induced-Transparency Media with Refractive Index Modulation
We predict the existence of a new type of spatiotemporal solitons ("light
bullets") in two-dimensional self-induced-transparency media with refractive
index modulation in the direction transverse to that of pulse propagation.
These self-localized guided modes are found in an approximate analytical form,
their existence and stability being confirmed by numerical simulations, and may
have advantageous properties for signal transmission
Development of Uniform CdTe Pixel Detectors Based on Caltech ASIC
We have developed a large CdTe pixel detector with dimensions of 23.7 x 13.0
mm and a pixel size of 448 x 448 um^2. The detector is based on recent
technologies of an uniform CdTe single crystal, a two-dimensional ASIC, and
stud bump-bonding to connect pixel electrodes on the CdTe surface to the ASIC.
Good spectra are obtained from 1051 pixels out of total 1056 pixels. When we
operate the detector at -50 C, the energy resolution is 0.67 keV and 0.99 keV
at 14 keV and 60 keV, respectively. Week-long stability of the detector is
confirmed at operating temperatures of both -50 C and -20 C. The detector also
shows high uniformity: the peak positions for all pixels agree to within 0.82%,
and the average of the energy resolution is 1.04 keV at a temperature of -50 C.
When we normalized the peak area by the total counts detected by each pixel, a
variation of 2.1 % is obtained.Comment: 11pages, 17figures, accepted for publication in Proc. SPIE 200
Actively Contracting Bundles of Polar Filaments
We introduce a phenomenological model to study the properties of bundles of
polar filaments which interact via active elements. The stability of the
homogeneous state, the attractors of the dynamics in the unstable regime and
the tensile stress generated in the bundle are discussed. We find that the
interaction of parallel filaments can induce unstable behavior and is
responsible for active contraction and tension in the bundle. Interaction
between antiparallel filaments leads to filament sorting. Our model could apply
to simple contractile structures in cells such as stress fibers.Comment: 4 pages, 4 figures, RevTex, to appear in Phys. Rev. Let
Electronic structure investigation of CeB6 by means of soft X-ray scattering
The electronic structure of the heavy fermion compound CeB6 is probed by
resonant inelastic soft X-ray scattering using photon energies across the Ce 3d
and 4d absorption edges. The hybridization between the localized 4f orbitals
and the delocalized valence-band states is studied by identifying the different
spectral contributions from inelastic Raman scattering and normal fluorescence.
Pronounced energy-loss structures are observed below the elastic peak at both
the 3d and 4d thresholds. The origin and character of the inelastic scattering
structures are discussed in terms of charge-transfer excitations in connection
to the dipole allowed transitions with 4f character. Calculations within the
single impurity Anderson model with full multiplet effects are found to yield
consistent spectral functions to the experimental data.Comment: 9 pages, 4 figures, 1 table,
http://link.aps.org/doi/10.1103/PhysRevB.63.07510
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