324 research outputs found
Repetitive ischemic injuries to the kidneys result in lymph node fibrosis and impaired healing
The contribution of the kidney-draining lymph node (KLN) to the pathogenesis of ischemia-reperfusion injury (IRI) of the kidney and its subsequent recovery has not been explored in depth. In addition, the mechanism by which repetitive IRI contributes to renal fibrosis remains poorly understood. Herein, we have found that IRI of the kidney is associated with expansion of high endothelial venules (HEVs) and activation of fibroblastic reticular cells (FRCs) in the KLN, as demonstrated by significant expansion in the extracellular matrix. The lymphotoxin \u3b1 signaling pathway mediates activation of FRCs, and chronic treatment with lymphotoxin \u3b2 receptor-immunoglobulin fusion protein (LT\u3b2r-Ig) resulted in marked alteration of the KLN as well as augmentation of renal fibrosis. Depletion of FRCs reduced T cell activation in the KLN and ameliorated renal injury in acute IRI. Repetitive renal IRI was associated with senescence of FRCs, fibrosis of the KLN, and renal scarring, which were ameliorated by FRC administration. Therefore, our study emphasizes the critical role of FRCs in both the initiation and repair phases of injury following IRI of the kidney
Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set
We report a measurement of the bottom-strange meson mixing phase \beta_s
using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays
in which the quark-flavor content of the bottom-strange meson is identified at
production. This measurement uses the full data set of proton-antiproton
collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment
at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity.
We report confidence regions in the two-dimensional space of \beta_s and the
B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2,
-1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in
agreement with the standard model expectation. Assuming the standard model
value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +-
0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +-
0.009 (syst) ps, which are consistent and competitive with determinations by
other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012
Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC
Measurements of inclusive jet suppression in heavy ion collisions at the LHC
provide direct sensitivity to the physics of jet quenching. In a sample of
lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated
luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with
a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the
transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the
anti-kt algorithm with values for the distance parameter that determines the
nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of
the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp.
Jet production is found to be suppressed by approximately a factor of two in
the 10% most central collisions relative to peripheral collisions. Rcp varies
smoothly with centrality as characterized by the number of participating
nucleons. The observed suppression is only weakly dependent on jet radius and
transverse momentum. These results provide the first direct measurement of
inclusive jet suppression in heavy ion collisions and complement previous
measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables,
submitted to Physics Letters B. All figures including auxiliary figures are
available at
http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02
Entanglement or separability: The choice of how to factorize the algebra of a density matrix
We discuss the concept of how entanglement changes with respect to different
factorizations of the total algebra which describes the quantum states.
Depending on the considered factorization a quantum state appears either
entangled or separable. For pure states we always can switch unitarily between
separability and entanglement, however, for mixed states a minimal amount of
mixedness is needed. We discuss our general statements in detail for the
familiar case of qubits, the GHZ states, Werner states and Gisin states,
emphasizing their geometric features. As theorists we use and play with this
free choice of factorization, which is naturally fixed for an experimentalist.
For theorists it offers an extension of the interpretations and is adequate to
generalizations, as we point out in the examples of quantum teleportation and
entanglement swapping.Comment: 29 pages, 9 figures. Introduction, Conclusion and References have
been extended in v
Saethre-Chotzen syndrome : cranofacial anomalies caused by genetic changes in the TWIST gene
In this thesis, one of the most frequently occurring and most variable craniosynostosis
syndromes was investigated; Saethre-Chotzen syndrome. Craniosynostosis is the premature
obliteration of cranial sutures in the developing embryo. It can also occur in the first few
months of life. Saethre-Chotzen syndrome is, besides craniosynostosis, characterized by
specific facial and limb abnormalities, of which the most frequently reported are ptosis,
prominent crus helicis, cutaneous syndactyly of digit 2 and 3 on both hands and feet, and
broad halluces. Saethre-Chotzen syndrome has been linked to the TWIST gene on
chromosome 7p21.1. Mutations in and variably sized deletions of this gene can be found in
patients with clinical features of Saethre-Chotzen syndrome. The latter, TWIST deletions,
often also include part of the surrounding chromosome 7p and are reported to be associated
with mental retardation. In Saethre-Chotzen patients, in whom neither a mutation nor a
deletion of TWIST had been found, the FGFR3 P250R mutation was in some cases detected.
This mutation has specifically been linked to Muenke syndrome that is characterized by unior
bicoronal synostosis and slight facial dysmorphology. However, a Saethre-Chotzen like
phenotype can also result from this mutation.
Because of the possible overlap of Saethre-Chotzen with Muenke syndrome, these syndromes
were studied in order to provide clinical criteria that discriminate between the two (chapter 4).
Many phenotypic features occur in both syndromes. In addition, although unicoronal
synostosis occurs slightly more frequently in Muenke syndrome, unicoronal and bicoronal
synostosis are seen in both syndromes. The discrimination between Saethre-Chotzen and
Muenke is often not made easily and the associated genes, TWIST and FGFR3, respectively,
are simultaneously tested for pathogenic m
W boson polarization measurement in the ttbar dilepton channel using the CDF II Detector
We present a measurement of boson polarization in top-quark decays in
events with decays to dilepton final states using of integrated luminosity in collisions collected by the
CDF II detector at the Tevatron. A simultaneous measurement of the fractions of
longitudinal () and right-handed () bosons yields the results
and . Combining this measurement
with our previous result based on single lepton final states, we obtain and . The results are consistent with standard
model expectation.Comment: Published in Phys. Lett.
Measurement of the Bs Lifetime in Fully and Partially Reconstructed Bs -> Ds- (phi pi-)X Decays in pbar-p Collisions at sqrt(s) = 1.96 TeV
We present a measurement of the Bs lifetime in fully and partially
reconstructed Bs -> Ds(phi pi)X decays in 1.3 fb-1 of pbar-p collisions at
sqrt(s) = 1.96 TeV collected by the CDF II detector at the Fermilab Tevatron.
We measure tau(Bs) = 1.518 +/- 0.041 (stat.) +/- 0.027 (syst.) ps. The ratio of
this result and the world average B0 lifetime yields tau(Bs)/tau(B0) = 0.99
+/-0.03, which is in agreement with recent theoretical predictions.Comment: submitted to Phys. Rev. Let
Observation of the structure in the Mass Spectrum in cays
The observation of the structure in decays produced in collisions at \sqrt{s}=1.96~\TeV is
reported with a statistical significance greater than 5 standard deviations. A
fit to the mass spectrum is performed assuming the presence of a
Breit-Wigner resonance. The fit yields a signal of resonance
events, and resonance mass and width of
4143.4^{+2.9}_{-3.0}(\mathrm{stat})\pm0.6(\mathrm{syst})~\MeVcc and
15.3^{+10.4}_{-6.1}(\mathrm{stat})\pm2.5(\mathrm{syst})~\MeVcc respectively.
The parameters of this resonance-like structure are consistent with values
reported from an earlier CDF analysis.Comment: 7 pages, 2 figures, submited to Phys. Rev. Let
Measurement of the ttbar Production Cross Section in ppbar collisions at sqrt s = 1.96 TeV in the All Hadronic Decay Mode
We report a measurement of the ttbar production cross section using the
CDF-II detector at the Fermilab Tevatron. The analysis is performed using 311
pb-1 of ppbar collisions at sqrt(s)=1.96 TeV. The data consist of events
selected with six or more hadronic jets with additional kinematic requirements.
At least one of these jets must be identified as a b-quark jet by the
reconstruction of a secondary vertex. The cross section is measured to be
sigma(tbart)=7.5+-2.1(stat.)+3.3-2.2(syst.)+0.5-0.4(lumi.) pb, which is
consistent with the standard model prediction.Comment: By CDF collaboratio
Search for long-lived doubly charged Higgs bosons in p(p)over-bar collisions at root s=1.96 TeV
We present a search for long-lived doubly charged Higgs bosons (H+/-+/-), with signatures of high ionization energy loss and muonlike penetration. We use 292 pb(-1) of data collected in p (p) over bar collisions at root s=1.96 TeV by the CDF II detector at the Fermilab Tevatron. Observing no evidence of long-lived doubly charged particle production, we exclude H-L(+/-+/-) and H-R(+/-+/-) bosons with masses below 133 GeV/c(2) and 109 GeV/c(2), respectively. In the degenerate case we exclude H+/-+/- mass below 146 GeV/c(2). All limits are quoted at the 95% confidence level
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