169 research outputs found
Evolution of Non-Equilibrium Profile in Adsorbate Layer under Compressive Strain
We investigate the time evolution of an initial step profile separating a
bare substrate region from the rest of the compressively strained adsorbate
layer near a commensurate to incommensurate transition. The rate of profile
evolution as a function of the mismatch, coverage and the strength of the
substrate potential are determined by Brownian molecular dynamics simulations.
We find that the results are qualitatively similar to those observed for the
Pb/Si(111) system. The anomalously fast time evolution and sharpness of the
non-equilibrium profile can be understood through the domain wall creation at
the boundary and its subsequent diffusion into the interior of the adsorbate
layer.Comment: 6 pages, 7 figures, Tribology Letter
Elimination of Unwanted Electro-magnetic Noise in a GTEM Cell for IC Emission Measurements
The IEC 61967 standards suggest an integrated circuits (ICs electromagnetic emission measurement technique by mounting IC test board on TEM/GTEM cell wall. It appears that the method has limited device under test (DUT) rotation in horizontal position and neglected vertical polarization while rotating in horizontal position. In general, the electromagnetic emission of a device at an observation point is contributed by both the horizontal and vertical polarizations. The limitation can be overcome by conducting the emission test in Gigahertz Transverse Electromagnetic Mode (GTEM). However, supporting components on the board and interface cable are the major concerns which may contribute unwanted noise to interfere with the measurement. In this paper, we present an effort to tackle these crucial matters in the setup in order to quantify IC electromagnetic emission in GTEM cell with application of basic electromagnetic compatibility (EMC) measurement approaches such as shielding, grounding and suppression using ferromagnetic material. The results show strong evidence on the effectiveness of the technique proposed to ensure reliable IC emission measurement in GTEM cell
Tidal Dwarf Galaxies at Intermediate Redshifts
We present the first attempt at measuring the production rate of tidal dwarf
galaxies (TDGs) and estimating their contribution to the overall dwarf
population. Using HST/ACS deep imaging data from GOODS and GEMS surveys in
conjunction with photometric redshifts from COMBO-17 survey, we performed a
morphological analysis for a sample of merging/interacting galaxies in the
Extended Chandra Deep Field South and identified tidal dwarf candidates in the
rest-frame optical bands. We estimated a production rate about 1.4 {\times}
10^{-5} per Gyr per comoving volume for long-lived TDGs with stellar mass 3
{\times} 10^{8-9} solar mass at 0.5<z<1.1. Together with galaxy merger rates
and TDG survival rate from the literature, our results suggest that only a
marginal fraction (less than 10%) of dwarf galaxies in the local universe could
be tidally-originated. TDGs in our sample are on average bluer than their host
galaxies in the optical. Stellar population modelling of optical to
near-infrared spectral energy distributions (SEDs) for two TDGs favors a burst
component with age 400/200 Myr and stellar mass 40%/26% of the total,
indicating that a young stellar population newly formed in TDGs. This is
consistent with the episodic star formation histories found for nearby TDGs.Comment: 9 pages, 5 figures, Accepted for publication in Astrophysics & Space
Scienc
Measurements of the Mass and Full-Width of the Meson
In a sample of 58 million events collected with the BES II detector,
the process J/ is observed in five different decay
channels: , , (with ), (with
) and . From a combined fit of all five
channels, we determine the mass and full-width of to be
MeV/ and
MeV/.Comment: 9 pages, 2 figures and 4 table. Submitted to Phys. Lett.
A Measurement of Psi(2S) Resonance Parameters
Cross sections for e+e- to hadons, pi+pi- J/Psi, and mu+mu- have been
measured in the vicinity of the Psi(2S) resonance using the BESII detector
operated at the BEPC. The Psi(2S) total width; partial widths to hadrons,
pi+pi- J/Psi, muons; and corresponding branching fractions have been determined
to be Gamma(total)= (264+-27) keV; Gamma(hadron)= (258+-26) keV, Gamma(mu)=
(2.44+-0.21) keV, and Gamma(pi+pi- J/Psi)= (85+-8.7) keV; and Br(hadron)=
(97.79+-0.15)%, Br(pi+pi- J/Psi)= (32+-1.4)%, Br(mu)= (0.93+-0.08)%,
respectively.Comment: 8 pages, 6 figure
Elotuzumab, lenalidomide, and dexamethasone in RRMM: final overall survival results from the phase 3 randomized ELOQUENT-2 study
Prolonging overall survival (OS) remains an unmet need in relapsed or refractory multiple myeloma (RRMM). In
ELOQUENT-2 (NCT01239797), elotuzumab plus lenalidomide/dexamethasone (ERd) significantly improved
progression-free survival (PFS) versus lenalidomide/dexamethasone (Rd) in patients with RRMM and 1–3 prior lines of
therapy (LoTs). We report results from the pre-planned final OS analysis after a minimum follow-up of 70.6 months, the
longest reported for an antibody-based triplet in RRMM. Overall, 646 patients with RRMM and 1–3 prior LoTs were
randomized 1:1 to ERd or Rd. PFS and overall response rate were co-primary endpoints. OS was a key secondary
endpoint, with the final analysis planned after 427 deaths. ERd demonstrated a statistically significant 8.7-month
improvement in OS versus Rd (median, 48.3 vs 39.6 months; hazard ratio, 0.82 [95.4% Cl, 0.68–1.00]; P = 0.0408 [less
than allotted α of 0.046]), which was consistently observed across key predefined subgroups. No additional safety
signals with ERd at extended follow-up were reported. ERd is the first antibody-based triplet regimen shown to
significantly prolong OS in patients with RRMM and 1–3 prior LoTs. The magnitude of OS benefit was greatest among
patients with adverse prognostic factors, including older age, ISS stage III, IMWG high-risk disease, and 2–3 prior LoTs
Physical activity attenuates the influence of FTO variants on obesity risk: A meta-analysis of 218,166 adults and 19,268 children
Background: The FTO gene harbors the strongest known susceptibility locus for obesity. While many individual studies have suggested that physical activity (PA) may attenuate the effect of FTO on obesity risk, other studies have not been able to confirm this interaction. To confirm or refute unambiguously whether PA attenuates the association of FTO with obesity risk, we meta-analyzed data from 45 studies of adults (n = 218,166) and nine studies of children and adolescents (n = 19,268). Methods and Findings: All studies identified to have data on the FTO rs9939609 variant (or any proxy [r2>0.8]) and PA were invited to participate, regardless of ethnicity or age of the participants. PA was standardized by categorizing it into a dichotomous variable (physically inactive versus active) in each study. Overall, 25% of adults and 13% of children were categorized as inactive. Interaction analyses were performed within each study by including the FTO×PA interaction term in an additive model, adjusting for age and sex. Subsequently, random effects meta-analysis was used to pool the interaction terms. In adults, the minor (A-) allele of rs9939609 increased the odds of obesity by 1.23-fold/allele (95% CI 1.20-1.26), but PA attenuated this effect (pinteraction= 0.001). More specifically, the minor allele of rs9939609 increased the odds of obesity less in the physically active group (odds ratio = 1.22/allele, 95% CI 1.19-1.25) than in the inactive group (odds ratio = 1.30/allele, 95% CI 1.24-1.36). No such interaction was found in children and adolescents. Concl
A new strategy for enhancing imputation quality of rare variants from next-generation sequencing data via combining SNP and exome chip data
Background: Rare variants have gathered increasing attention as a possible alternative source of missing heritability. Since next generation sequencing technology is not yet cost-effective for large-scale genomic studies, a widely used alternative approach is imputation. However, the imputation approach may be limited by the low accuracy of the imputed rare variants. To improve imputation accuracy of rare variants, various approaches have been suggested, including increasing the sample size of the reference panel, using sequencing data from study-specific samples (i.e., specific populations), and using local reference panels by genotyping or sequencing a subset of study samples. While these approaches mainly utilize reference panels, imputation accuracy of rare variants can also be increased by using exome chips containing rare variants. The exome chip contains 250 K rare variants selected from the discovered variants of about 12,000 sequenced samples. If exome chip data are available for previously genotyped samples, the combined approach using a genotype panel of merged data, including exome chips and SNP chips, should increase the imputation accuracy of rare variants. Results: In this study, we describe a combined imputation which uses both exome chip and SNP chip data simultaneously as a genotype panel. The effectiveness and performance of the combined approach was demonstrated using a reference panel of 848 samples constructed using exome sequencing data from the T2D-GENES consortium and 5,349 sample genotype panels consisting of an exome chip and SNP chip. As a result, the combined approach increased imputation quality up to 11 %, and genomic coverage for rare variants up to 117.7 % (MAF < 1 %), compared to imputation using the SNP chip alone. Also, we investigated the systematic effect of reference panels on imputation quality using five reference panels and three genotype panels. The best performing approach was the combination of the study specific reference panel and the genotype panel of combined data. Conclusions: Our study demonstrates that combined datasets, including SNP chips and exome chips, enhances both the imputation quality and genomic coverage of rare variants
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