3,897 research outputs found
Sub-arcsec Observations of NGC 7538 IRS 1: Continuum Distribution and Dynamics of Molecular Gas
We report new results based on the analysis of the SMA and CARMA observations
of NGC 7538\,IRS\,1 at 1.3 and 3.4 mm with sub-arcsec resolutions. With angular
resolutions 0\farcs7, the SMA and CARMA observations show that the
continuum emission at 1.3 and 3.4 mm from the hyper-compact \ion{H}{2} region
IRS\,1 is dominated by a compact source with a tail-like extended structure to
the southwest of IRS\,1. With a CARMA B-array image at 1.3 mm convolved to
0\farcs1, we resolve the hyper-compact \ion{H}{2} region into two components:
an unresolved hyper-compact core, and a north-south extension with linear sizes
of AU and 2000 AU, respectively. The fine structure observed with
CARMA is in good agreement with the previous VLA results at centimeter
wavelengths, suggesting that the hyper-compact \ion{H}{2} region at the center
of IRS\,1 is associated with an ionized bipolar outflow. We image the molecular
lines OCS(19-18) and CHCN(12-11) as well as CO(2-1) surrounding
IRS\,1, showing a velocity gradient along the southwest-northeast direction.
The spectral line profiles in CO(2-1), CO(2-1), and HCN(1-0) observed
toward IRS\,1 show broad redshifted absorption, providing evidence for gas
infall with rates in the range of M yr
inferred from our observations.Comment: 19 pages, 14 figure
Improving Scene Text Image Super-resolution via Dual Prior Modulation Network
Scene text image super-resolution (STISR) aims to simultaneously increase the
resolution and legibility of the text images, and the resulting images will
significantly affect the performance of downstream tasks. Although numerous
progress has been made, existing approaches raise two crucial issues: (1) They
neglect the global structure of the text, which bounds the semantic determinism
of the scene text. (2) The priors, e.g., text prior or stroke prior, employed
in existing works, are extracted from pre-trained text recognizers. That said,
such priors suffer from the domain gap including low resolution and blurriness
caused by poor imaging conditions, leading to incorrect guidance. Our work
addresses these gaps and proposes a plug-and-play module dubbed Dual Prior
Modulation Network (DPMN), which leverages dual image-level priors to bring
performance gain over existing approaches. Specifically, two types of
prior-guided refinement modules, each using the text mask or graphic
recognition result of the low-quality SR image from the preceding layer, are
designed to improve the structural clarity and semantic accuracy of the text,
respectively. The following attention mechanism hence modulates two
quality-enhanced images to attain a superior SR result. Extensive experiments
validate that our method improves the image quality and boosts the performance
of downstream tasks over five typical approaches on the benchmark. Substantial
visualizations and ablation studies demonstrate the advantages of the proposed
DPMN. Code is available at: https://github.com/jdfxzzy/DPMN.Comment: Accepted by AAAI-202
Effect of Thiazolidinedione Amide on Insulin Resistance, Creactive Protein and Endothelial Function in Young Women with Polycystic Ovary Syndrome
Purpose: To investigate the effect of thiazolidinedione amide (TZDA) treatment on high-sensitivity Creactive protein (hsCRP) levels and endothelial dysfunction in patients with polycystic ovary syndrome (PCOS).Methods: Twenty five women (mean age 24.7 ± 3.9 years; mean body mass index (BMI), 23.2 ± 4.0 kg/m2) with PCOS were treated with 15 μM TZDA daily for 12 months. Serum levels of testosterone, leutenizing hormone (LH), follicle stimulating hormone (FSH), sex hormone-binding globulin (SHBG), insulin and hsCRP were measured. BMI, hirsutism scores and insulin sensitivity indices were also calculated prior to and after TZDA treatment. Brachial artery responses to stimuli was used to measure arterial endothelium and smooth muscle function prior to and after the treatment.Results: TZDA treatment caused a significant (p < 0.05) decrease in serum testosterone from 93.1 ± 40.3 to 54.8 ± 19.5 ng/dl and fasting insulin concentration from 11.9 ± 6.8 to 9.23 ± 5.13 U/mL. Insulin resistance index significantly (p < 0.05) improved and hirsutism score decreased significantly from 11.6 ± 2.0 to 6.8 ± 2.0. BMI, waist circumference, serum total cholesterol, low-density lipoprotein (LDL)- cholesterol, FSH and LH levels remained almost unchanged. Twenty-four of the women reverted to regular menstrual cycles. SHBG levels showed a significant (p < 0.05) increase from 24.8 ± 9.5 to 49.1 ± 13.5 nmol/L after TZDA treatment. Serum hsCRP levels decreased (p < 0.05) from 0.25 ± 0.1 to 0.09 ± 0.02 mg/dL while endothelium-dependent vascular responses significantly improved (p < 0.05) following TZDA treatment (9.9 ± 3.9 vs 16.4 ± 5.1%).Conclusion: TZDA treatment improves insulin sensitivity, decreases androgen production and improves endothelial dysfunction in young women with PCOS.Keywords: Thiazolidinedione amide, Insulin sensitivity, Endothelial dysfunction, Polycystic ovary syndrom
The ultra-low-frequency shear modes of 2-4 layer graphenes observed in their scroll structures at edges
The in-plane shear modes between neighbor-layers of 2-4 layer graphenes (LGs)
and the corresponding graphene scrolls rolled up by 2-4LGs were investigated by
Raman scattering. In contrast to that just one shear mode was observed in
3-4LGs, all the shear modes of 3-4LGs were observed in 3-4 layer scrolls (LSs),
whose frequencies agree well with the theoretical predication by both a
force-constant model and a linear chain model. In comparison to the broad width
(about 12cm) for the G band in graphite, all the shear modes exhibit an
intrinsic line width of about 1.0 cm. The local electronic structures
dependent on the local staking configurations enhance the intensity of the
shear modes in corresponding 2-4LSs zones, which makes it possible to observe
all the shear modes. It provides a direct evidence that how the band structures
of FLGs can be sensitive to local staking configurations. This result can be
extended to n layer graphene (n > 4) for the understanding of the basic phonon
properties of multi-layer graphenes. This observation of all-scale shear modes
can be foreseen in other 2D materials with similar scroll structures.Comment: 14 pages, 5 figure
CD73 promotes proliferation and migration of human cervical cancer cells independent of its enzyme activity
100Â ÎźM Adenosine treatment did not change the expression of EGFR, VEGF and Akt. (JPG 335 kb
Observation of the chiral anomaly induced negative magneto-resistance in 3D Weyl semi-metal TaAs
Weyl semi-metal is the three dimensional analog of graphene. According to the
quantum field theory, the appearance of Weyl points near the Fermi level will
cause novel transport phenomena related to chiral anomaly. In the present
paper, we report the first experimental evidence for the long-anticipated
negative magneto-resistance generated by the chiral anomaly in a newly
predicted time-reversal invariant Weyl semi-metal material TaAs. Clear
Shubnikov de Haas oscillations (SdH) have been detected starting from very weak
magnetic field. Analysis of the SdH peaks gives the Berry phase accumulated
along the cyclotron orbits to be {\pi}, indicating the existence of Weyl
points.Comment: Submitted in February'1
- …