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Proteomic analyses of primary human villous trophoblasts exposed to flame retardant BDE-47 using SWATH-MS
Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants and recognized developmental toxicants that are detectable in placental tissues. Higher levels of in utero PBDE exposure have been associated with an increased risk of adverse birth outcomes. During pregnancy, cytotrophoblasts (CTBs) from the placenta play critical roles in the formation of the maternal-fetal interface via uterine invasion and vascular remodeling. The differentiation of these cells towards an invasive phenotype is crucial for proper placental development. We previously have shown that BDE-47 can impact CTB viability and hinder the ability of these cells to migrate and invade. To expand on potential toxicological mechanisms, we utilized quantitative proteomic approaches to identify changes in the global proteome of mid-gestation primary human CTBs after exposure to BDE-47. Using sequential window acquisition of all theoretical fragment-ion spectra (SWATH), we identified 3024 proteins in our CTB model of differentiation/invasion. Over 200 proteins were impacted as a function of BDE-47 exposure (1 μM and 5 μM) across the treatment period (15, 24, and 39 h). The differentially expressed molecules displayed time- and concentration-dependent changes in expression and were enriched in pathways associated with aggregatory and adhesive processes. Network analysis identified CYFIP1, a molecule previously unexplored in a placental context, to be dysregulated at BDE-47 concentrations previously seen to impact CTB migration/invasion. Our SWATH-MS dataset thus demonstrates BDE-47 impacts the global proteome of differentiating CTBs and serves as a valuable resource for further understanding of the relationship between environmental chemical exposures and placental development and function. AVAILABILITY OF DATA AND MATERIAL: Raw chromatograms are deposited on the MassIVE proteomic database (https://massive.ucsd.edu) under accession number MSV000087870. Normalized relative abundances are also available as Table S1
Two-dimensional Navier--Stokes simulation of deformation and break up of liquid patches
The large deformations and break up of circular 2D liquid patches in a high
Reynolds number (Re=1000) gas flow are investigated numerically. The 2D, plane
flow Navier--Stokes equations are directly solved with explicit tracking of the
interface between the two phases and a new algorithm for surface tension. The
numerical method is able to pursue the simulation beyond the breaking or
coalescence of droplets. The simulations are able to unveil the intriguing
details of the non-linear interplay between the deforming droplets and the
vortical structures in the droplet's wake.Comment: 13 pages including 4 postscript figures; Revised version as
resubmitted to PRL. Title has change
Early phase observations of extremely luminous Type Ia Supernova 2009dc
We present early phase observations in optical and near-infrared wavelengths
for the extremely luminous Type Ia supernova (SN Ia) 2009dc. The decline rate
of the light curve is , which is one of the
slowest among SNe Ia. The peak -band absolute magnitude is mag even if the host extinction is mag. It reaches
mag for the host extinction of mag as
inferred from the observed Na {\sc i} D line absorption in the host. Our
-band photometry shows that the SN is one of the most luminous SNe Ia
also in near-infrared wavelengths. These results indicate that SN 2009dc
belongs to the most luminous class of SNe Ia, like SN 2003fg and SN 2006gz. We
estimate the ejected Ni mass of \Msun for no host
extinction case (or 1.6 0.4 M for the host extinction of
mag). The C {\sc ii} 6580 absorption line keeps visible
until a week after maximum, which diminished in SN 2006gz before its maximum
brightness. The line velocity of Si {\sc ii} 6355 is about 8000 km
s around the maximum, being considerably slower than that of SN 2006gz,
while comparable to that of SN 2003fg. The velocity of the C {\sc ii} line is
almost comparable to that of the Si {\sc ii}. The presence of the carbon line
suggests that thick unburned C+O layers remain after the explosion. SN 2009dc
is a plausible candidate of the super-Chandrasekhar mass SNe Ia
Recoil Polarization Measurements of the Proton Electromagnetic Form Factor Ratio to Q^2 = 8.5 GeV^2
Among the most fundamental observables of nucleon structure, electromagnetic
form factors are a crucial benchmark for modern calculations describing the
strong interaction dynamics of the nucleon's quark constituents; indeed, recent
proton data have attracted intense theoretical interest. In this letter, we
report new measurements of the proton electromagnetic form factor ratio using
the recoil polarization method, at momentum transfers Q2=5.2, 6.7, and 8.5
GeV2. By extending the range of Q2 for which GEp is accurately determined by
more than 50%, these measurements will provide significant constraints on
models of nucleon structure in the non-perturbative regime
Single Spin Asymmetries of Inclusive Hadrons Produced in Electron Scattering from a Transversely Polarized He Target
We report the first measurement of target single-spin asymmetries (A) in
the inclusive hadron production reaction,
+, using a transversely polarized
He target. The experiment was conducted at Jefferson Lab in Hall A using a
5.9-GeV electron beam. Three types of hadrons (,
and proton) were detected in the transverse hadron momentum range 0.54
0.74 GeV/c. The range of for pions was -0.29 -0.23 and for kaons
-0.25 -0.18. The observed asymmetry strongly depends on the type of
hadron. A positive asymmetry is observed for and . A
negative asymmetry is observed for . The magnitudes of the asymmetries
follow . The K and proton
asymmetries are consistent with zero within the experimental uncertainties. The
and asymmetries measured for the He target and
extracted for neutrons are opposite in sign with a small increase observed as a
function of .Comment: Updated version, submitted to Phys. Rev.
Double Spin Asymmetries of Inclusive Hadron Electroproductions from a Transversely Polarized Target
We report the measurement of beam-target double-spin asymmetries
() in the inclusive production of identified hadrons,
+, using a longitudinally
polarized 5.9 GeV electron beam and a transversely polarized
target. Hadrons (, and proton) were detected at
16 with an average momentum =2.35 GeV/c and a transverse
momentum () coverage from 0.60 to 0.68 GeV/c. Asymmetries from the
target were observed to be non-zero for production
when the target was polarized transversely in the horizontal plane. The
and asymmetries have opposite signs, analogous to the
behavior of in semi-inclusive deep-inelastic scattering.Comment: Published in PRC (92.015207), nuclear experiment, high-energy
experimen
Microwave Assisted Synthesis of Py-Im Polyamides
Microwave synthesis was utilized to rapidly build Py-Im polyamides in high yields and purity using Boc-protection chemistry on Kaiser oxime resin. A representative polyamide targeting the 5′-WGWWCW-3′ (W = A or T) subset of the consensus Androgen and Glucocorticoid Response Elements was synthesized in 56% yield after 20 linear steps and HPLC purification. It was confirmed by Mosher amide derivatization of the polyamide that a chiral α-amino acid does not racemize after several additional coupling steps
Single Spin Asymmetries in Charged Kaon Production from Semi-Inclusive Deep Inelastic Scattering on a Transversely Polarized Target
We report the first measurement of target single spin asymmetries of charged
kaons produced in semi-inclusive deep inelastic scattering of electrons off a
transversely polarized target. Both the Collins and Sivers
moments, which are related to the nucleon transversity and Sivers
distributions, respectively, are extracted over the kinematic range of
0.10.4 for and production. While the Collins and
Sivers moments for are consistent with zero within the experimental
uncertainties, both moments for favor negative values. The Sivers
moments are compared to the theoretical prediction from a phenomenological fit
to the world data. While the Sivers moments are consistent with the
prediction, the results differ from the prediction at the 2-sigma
level.Comment: 6 pages, 3 figure
Low Q^2 measurements of the proton form factor ratio
We present an updated extraction of the proton electromagnetic form factor
ratio, mu_p G_E/G_M, at low Q^2. The form factors are sensitive to the spatial
distribution of the proton, and precise measurements can be used to constrain
models of the proton. An improved selection of the elastic events and reduced
background contributions yielded a small systematic reduction in the ratio mu_p
G_E/G_M compared to the original analysis.Comment: 12 pages, 5 figures, archival paper for proton form factor extraction
from Jefferson Lab "LEDEX" experimen
Measurement of pretzelosity asymmetry of charged pion production in Semi-Inclusive Deep Inelastic Scattering on a polarized He target
An experiment to measure single-spin asymmetries in semi-inclusive production
of charged pions in deep-inelastic scattering on a transversely polarized
He target was performed at Jefferson Lab in the kinematic region of
and . The pretzelosity asymmetries on
He, which can be expressed as the convolution of the
transverse momentum dependent distribution functions and the Collins
fragmentation functions in the leading order, were measured for the first time.
Using the effective polarization approximation, we extracted the corresponding
neutron asymmetries from the measured He asymmetries and cross-section
ratios between the proton and He. Our results show that for both
on He and on the neutron the pretzelosity asymmetries are
consistent with zero within experimental uncertainties.Comment: 6 pages, 3 figures; enlarged the legends in Fig.3; added 3 citation
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