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Maternal Hyperleptinemia Increases Arterial Stiffening and Alters Vasodilatoy Responses to Insulin in Adult Male Mice Offspring
Cardiovascular disease (CVD) is the number one cause of death in the U.S., and exposure to adverse maternal environments has been associated with the development of CVD including hypertension. Gestational diabetes mellitus (GDM) is an adverse maternal environment that has been associated with metabolic and CVD outcomes in the offspring. Key features of GDM and CVD are maternal hyperleptinemia and vascular disfunction/remodeling, respectively. Yet, there is limited information on the effects of maternal hyperleptinemia has on the function and structure of the offspringâs resistance vasculature. We hypothesize that alterations in offspringâs resistance artery structure and function underlie programming mechanisms for cardiovascular disease that are associated with maternal hyperleptinemia and GDM. To test this hypothesis, we used Leprdb/+ mice dams, which exhibit maternal hyperleptinemia and wildtype (WT) as controls. Vascular function was assessed in WT male offspring of control and hyperleptinemic dams at 31 weeks of age, after half the offspring had been fed a high fat diet (HFD) for 6 weeks. On a standard diet (SD), offspring of hyperleptinemic dams had mesenteric arteries with larger internal diameters than those of WT dams (258.36Âą14.99 vs 233.65Âą9.36 Îźm, p<0.05) indicative of outwardly remodeled, and enhanced maximal vasodilatory responses to insulin (39.97Âą6.71 vs 32.23Âą5.07 %, p<0.05). In offspring of WT, but not hyperleptinemic dams, HFD increased vessel wall cross-sectional area (18590.01Âą1251.16 vs 12807.20Âą1060.70 Îźm2, p<0.05), and enhanced the maximal vasodilatory response to acetylcholine (33.74Âą4.92 vs 21.86Âą2.73 %, p<0.05). HFD reduced the maximal response to insulin in offspring of hyperleptinemic dams compared to their WT and lean controls (21.88Âą3.80 vs 37.42Âą7.84 and 39.97Âą6.71 % respectively, p<0.05). Offspring of hyperleptinemic dams fed a HFD had increased elastic moduli normalized as a function of the percolation of the internal elastic lamina compared to their WT and lean controls (0.53Âą0.038 vs 0.34Âą0.023 and 0.38Âą0.032 Ă106 dynes/cm2 respectively, p<0.05). Offspring of hyperleptinemic dams also had stiffer arteries at high pressure under both dietary conditions (2.36Âą0.35 vs 1.45Âą0.11 Ă106 dynes/cm2, p<0.05). We conclude that when mice were fed a SD, maternal hyperleptinemia had beneficial effects to offspringâs vascular health, but did not protect offspring fed a HFD. Furthermore, maternal hyperleptinemia induced arterial stiffness in offspring regardless of diet. These results suggest that GDM programs offspring vascular function and structure through mechanisms that may be in part dependent on circulating maternal leptin levels and are differentially affected by postnatal developmental exposures
Evaluation of different bowel preparations for small bowel capsule endoscopy: a prospective, randomized, controlled study
To obtain an adequate view of the whole small
intestine during capsule endoscopy (CE) a clear liquid diet and overnight fasting
is recommended. However, intestinal content can hamper vision in spite of these
measures. Our aim was to evaluate tolerance and degree of intestinal cleanliness
during CE following three types of bowel preparation. PATIENTS AND METHODS: This
was a prospective, multicenter, randomized, controlled study. Two-hundred
ninety-one patients underwent one of the following preparations: 4 L of clear
liquids (CL) (group A; 92 patients); 90 mL of aqueous sodium phosphate (group B;
89 patients); or 4 L of a polyethylene glycol electrolyte solution (group C; 92
patients). The degree of cleanliness of the small bowel was classified by blinded
examiners according to four categories (excellent, good, fair or poor). The
degree of patient satisfaction, gastric and small bowel transit times, and
diagnostic yield were measured. RESULTS: The degree of cleanliness did not differ
significantly between the groups (P = 0.496). Interobserver concordance was fair
(k = 0.38). No significant differences were detected between the diagnostic
yields of the CE (P = 0.601). Gastric transit time was 35.7 +/- 3.7 min (group
A), 46.1 +/- 8.6 min (group B) and 34.6 +/- 5.0 min (group C) (P = 0.417).
Small-intestinal transit time was 276.9 +/- 10.7 min (group A), 249.7 +/- 13.1
min (group B) and 245.6 +/- 11.6 min (group C) (P = 0.120). CL was the best
tolerated preparation. Compliance with the bowel preparation regimen was lowest
in group C (P = 0.008). CONCLUSIONS: A clear liquid diet and overnight fasting is
sufficient to achieve an adequate level of cleanliness and is better tolerated by
patients than other forms of preparation
ALMA Observations of Asteroid 3 Juno at 60 Kilometer Resolution
We present Atacama Large Millimeter/submillimeter Array (ALMA) 1.3 mm
continuum images of the asteroid 3 Juno obtained with an angular resolution of
0.042 arcseconds (60 km at 1.97 AU). The data were obtained over a single 4.4
hr interval, which covers 60% of the 7.2 hr rotation period, approximately
centered on local transit. A sequence of ten consecutive images reveals
continuous changes in the asteroid's profile and apparent shape, in good
agreement with the sky projection of the three-dimensional model of the
Database of Asteroid Models from Inversion Techniques. We measure a geometric
mean diameter of 259pm4 km, in good agreement with past estimates from a
variety of techniques and wavelengths. Due to the viewing angle and inclination
of the rotational pole, the southern hemisphere dominates all of the images.
The median peak brightness temperature is 215pm13 K, while the median over the
whole surface is 197pm15 K. With the unprecedented resolution of ALMA, we find
that the brightness temperature varies across the surface with higher values
correlated to the subsolar point and afternoon areas, and lower values beyond
the evening terminator. The dominance of the subsolar point is accentuated in
the final four images, suggesting a reduction in the thermal inertia of the
regolith at the corresponding longitudes, which are possibly correlated to the
location of the putative large impact crater. These results demonstrate ALMA's
potential to resolve thermal emission from the surface of main belt asteroids,
and to measure accurately their position, geometric shape, rotational period,
and soil characteristics.Comment: 8 pages, 3 figures, 2 tables, accepted for publication in the
Astrophysical Journal Letter
First Results from High Angular Resolution ALMA Observations Toward the HL Tau Region
We present Atacama Large Millimeter/submillimeter Array (ALMA) observations
from the 2014 Long Baseline Campaign in dust continuum and spectral line
emission from the HL Tau region. The continuum images at wavelengths of 2.9,
1.3, and 0.87 mm have unprecedented angular resolutions of 0.075 arcseconds (10
AU) to 0.025 arcseconds (3.5 AU), revealing an astonishing level of detail in
the circumstellar disk surrounding the young solar analogue HL Tau, with a
pattern of bright and dark rings observed at all wavelengths. By fitting
ellipses to the most distinct rings, we measure precise values for the disk
inclination (46.72pm0.05 degrees) and position angle (+138.02pm0.07 degrees).
We obtain a high-fidelity image of the 1.0 mm spectral index (), which
ranges from in the optically-thick central peak and two
brightest rings, increasing to 2.3-3.0 in the dark rings. The dark rings are
not devoid of emission, we estimate a grain emissivity index of 0.8 for the
innermost dark ring and lower for subsequent dark rings, consistent with some
degree of grain growth and evolution. Additional clues that the rings arise
from planet formation include an increase in their central offsets with radius
and the presence of numerous orbital resonances. At a resolution of 35 AU, we
resolve the molecular component of the disk in HCO+ (1-0) which exhibits a
pattern over LSR velocities from 2-12 km/s consistent with Keplerian motion
around a ~1.3 solar mass star, although complicated by absorption at low
blue-shifted velocities. We also serendipitously detect and resolve the nearby
protostars XZ Tau (A/B) and LkHa358 at 2.9 mm.Comment: 11 pages, 5 figures, 2 tables, accepted for publication in the
Astrophysical Journal Letter
MINERvA neutrino detector response measured with test beam data
The MINERvA collaboration operated a scaled-down replica of the solid
scintillator tracking and sampling calorimeter regions of the MINERvA detector
in a hadron test beam at the Fermilab Test Beam Facility. This article reports
measurements with samples of protons, pions, and electrons from 0.35 to 2.0
GeV/c momentum. The calorimetric response to protons, pions, and electrons are
obtained from these data. A measurement of the parameter in Birks' law and an
estimate of the tracking efficiency are extracted from the proton sample.
Overall the data are well described by a Geant4-based Monte Carlo simulation of
the detector and particle interactions with agreements better than 4%, though
some features of the data are not precisely modeled. These measurements are
used to tune the MINERvA detector simulation and evaluate systematic
uncertainties in support of the MINERvA neutrino cross section measurement
program.Comment: as accepted by NIM
An Overview of the 2014 ALMA Long Baseline Campaign
A major goal of the Atacama Large Millimeter/submillimeter Array (ALMA) is to
make accurate images with resolutions of tens of milliarcseconds, which at
submillimeter (submm) wavelengths requires baselines up to ~15 km. To develop
and test this capability, a Long Baseline Campaign (LBC) was carried out from
September to late November 2014, culminating in end-to-end observations,
calibrations, and imaging of selected Science Verification (SV) targets. This
paper presents an overview of the campaign and its main results, including an
investigation of the short-term coherence properties and systematic phase
errors over the long baselines at the ALMA site, a summary of the SV targets
and observations, and recommendations for science observing strategies at long
baselines. Deep ALMA images of the quasar 3C138 at 97 and 241 GHz are also
compared to VLA 43 GHz results, demonstrating an agreement at a level of a few
percent. As a result of the extensive program of LBC testing, the highly
successful SV imaging at long baselines achieved angular resolutions as fine as
19 mas at ~350 GHz. Observing with ALMA on baselines of up to 15 km is now
possible, and opens up new parameter space for submm astronomy.Comment: 11 pages, 7 figures, 2 tables; accepted for publication in the
Astrophysical Journal Letters; this version with small changes to
affiliation
Measurement of the cross-section and charge asymmetry of bosons produced in proton-proton collisions at TeV with the ATLAS detector
This paper presents measurements of the and cross-sections and the associated charge asymmetry as a
function of the absolute pseudorapidity of the decay muon. The data were
collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with
the ATLAS experiment at the LHC and correspond to a total integrated luminosity
of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements
varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the
1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured
with an uncertainty between 0.002 and 0.003. The results are compared with
predictions based on next-to-next-to-leading-order calculations with various
parton distribution functions and have the sensitivity to discriminate between
them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables,
submitted to EPJC. All figures including auxiliary figures are available at
https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13
Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV
A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay
channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7
TeV is presented. The data were collected at the LHC, with the CMS detector,
and correspond to an integrated luminosity of 4.6 inverse femtobarns. No
significant excess is observed above the background expectation, and upper
limits are set on the Higgs boson production cross section. The presence of the
standard model Higgs boson with a mass in the 270-440 GeV range is excluded at
95% confidence level.Comment: Submitted to JHE
Measurement of the t t-bar production cross section in the dilepton channel in pp collisions at sqrt(s) = 7 TeV
The t t-bar production cross section (sigma[t t-bar]) is measured in
proton-proton collisions at sqrt(s) = 7 TeV in data collected by the CMS
experiment, corresponding to an integrated luminosity of 2.3 inverse
femtobarns. The measurement is performed in events with two leptons (electrons
or muons) in the final state, at least two jets identified as jets originating
from b quarks, and the presence of an imbalance in transverse momentum. The
measured value of sigma[t t-bar] for a top-quark mass of 172.5 GeV is 161.9 +/-
2.5 (stat.) +5.1/-5.0 (syst.) +/- 3.6(lumi.) pb, consistent with the prediction
of the standard model.Comment: Replaced with published version. Included journal reference and DO
Combined search for the quarks of a sequential fourth generation
Results are presented from a search for a fourth generation of quarks
produced singly or in pairs in a data set corresponding to an integrated
luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in
2011. A novel strategy has been developed for a combined search for quarks of
the up and down type in decay channels with at least one isolated muon or
electron. Limits on the mass of the fourth-generation quarks and the relevant
Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a
simple extension of the standard model with a sequential fourth generation of
fermions. The existence of mass-degenerate fourth-generation quarks with masses
below 685 GeV is excluded at 95% confidence level for minimal off-diagonal
mixing between the third- and the fourth-generation quarks. With a mass
difference of 25 GeV between the quark masses, the obtained limit on the masses
of the fourth-generation quarks shifts by about +/- 20 GeV. These results
significantly reduce the allowed parameter space for a fourth generation of
fermions.Comment: Replaced with published version. Added journal reference and DO
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