230 research outputs found
Upper Limits on Electric and Weak Dipole Moments of W-Boson
The total cross-sections of the reaction e+e- --> W+W-, as measured at LEP-II
at centre-of-mass energies between 183 and 207 GeV are used to derive the upper
limits on the parameters of CP-violating (P-odd and C-even) triple gauge-boson
couplings WW\gamma and WWZ. The 95% CL limits |\widetilde{\kappa}_Z|<0.13 and
|\widetilde{\lambda}_Z|<0.31 are obtained assuming local SU(2)_L x U(1)_Y gauge
invariance. Our results are comparable with the previous ones obtained through
the analysis of the W decay products. We also discuss the upper limits on the
electric dipole moment (EDM) of the W-boson, which follow from the precision
measurements of the electron and neutron EDM.Comment: 9 pages, 4 figure
Temperature enhanced persistent currents and " periodicity"
We predict a non-monotonous temperature dependence of the persistent currents
in a ballistic ring coupled strongly to a stub in the grand canonical as well
as in the canonical case. We also show that such a non-monotonous temperature
dependence can naturally lead to a periodicity of the persistent
currents, where =h/e. There is a crossover temperature , below
which persistent currents increase in amplitude with temperature while they
decrease above this temperature. This is in contrast to persistent currents in
rings being monotonously affected by temperature. is parameter-dependent
but of the order of , where is the level spacing
of the isolated ring. For the grand-canonical case is half of that for
the canonical case.Comment: some typos correcte
Immune modulation in organ allograft recipients by single or multiple donor bone marrow infusions
Comparison of aquatic macrophyte community structure between natural wetlands and rice fields with different cultivation ages
Hypoxia-inducible factor-2α regulates the expression of TRAIL receptor DR5 in renal cancer cells
To understand the role of hypoxia-inducible factor (HIF)-2α in regulating sensitivity of renal cancer cells to tumor necrosis factor-related apoptosis inducing ligand (TRAIL)-induced apoptosis, we transfected wild-type and mutant von Hippel Lindau (VHL) proteins into TRAIL-sensitive, VHL-negative A498 cells. We find that wild-type VHL, but not the VHL mutants S65W and C162F that do not degrade HIF proteins, cause TRAIL resistance. Knock down of the HIF-2α protein by RNA interference (short hairpin RNA) blocked TRAIL-induced apoptosis, decreased the level of TRAIL receptor (DR5) protein and inhibited the transcription of DR5 messenger RNA. By using luciferase constructs containing the upstream region of the DR5 promoter, we demonstrate that HIF-2α stimulates the transcription of the DR5 gene by activating the upstream region between −448 and −1188. Because HIF-2α is thought to exert its effect on gene transcription by interacting with the Max protein partner of Myc in the Myc/Max dimer, small interfering RNAs to Myc were used to lower the levels of this protein. In multiple renal cancer cell lines decreasing the levels of Myc blocked the ability of HIF-2α to stimulate DR5 transcription. PS-341 (VELCADE, bortezomib), a proteasome inhibitor used to treat human cancer, increases the levels of both HIF-2α and c-Myc and elevates the level of DR5 in renal cancer, sensitizing renal cancer cells to TRAIL therapy. Similarly, increasing HIF-2α in prostate and lung cancer cell lines increased the levels of DR5. Thus, in renal cancer cell lines expressing HIF-2α, this protein plays a role in regulating the levels of the TRAIL receptor DR5
New Saurichthyid Actinopterygian Fishes from the Anisian (Middle Triassic) of Southwestern China
Understanding preventive behaviors among mid-Western African-American men: a pilot qualitative study of prostate screening
http://dx.doi.org/10.1016/j.jomh.2011.03.00
Search for Gravitational Waves Associated with Gamma-Ray Bursts Detected by Fermi and Swift during the LIGO-Virgo Run O3b
We search for gravitational-wave signals associated with gamma-ray bursts (GRBs) detected by the Fermi and Swift satellites during the second half of the third observing run of Advanced LIGO and Advanced Virgo (2019 November 1 15:00 UTC-2020 March 27 17:00 UTC). We conduct two independent searches: A generic gravitational-wave transients search to analyze 86 GRBs and an analysis to target binary mergers with at least one neutron star as short GRB progenitors for 17 events. We find no significant evidence for gravitational-wave signals associated with any of these GRBs. A weighted binomial test of the combined results finds no evidence for subthreshold gravitational-wave signals associated with this GRB ensemble either. We use several source types and signal morphologies during the searches, resulting in lower bounds on the estimated distance to each GRB. Finally, we constrain the population of low-luminosity short GRBs using results from the first to the third observing runs of Advanced LIGO and Advanced Virgo. The resulting population is in accordance with the local binary neutron star merger rate. © 2022. The Author(s). Published by the American Astronomical Society
Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run
Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo's third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those inferred from electromagnetic observations. We find no evidence for continuous gravitational waves, and set upper limits on the strain amplitude for each target. These limits are more constraining for seven of the targets than the spin-down limit defined by ascribing all rotational energy loss to gravitational radiation. In an additional search, we look in O3 data for long-duration (hours-months) transient gravitational waves in the aftermath of pulsar glitches for six targets with a total of nine glitches. We report two marginal outliers from this search, but find no clear evidence for such emission either. The resulting duration-dependent strain upper limits do not surpass indirect energy constraints for any of these targets. © 2022. The Author(s). Published by the American Astronomical Society
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