814 research outputs found
A multi-wavelength observation and investigation of six infrared dark clouds
Context. Infrared dark clouds (IRDCs) are ubiquitous in the Milky Way, yet
they play a crucial role in breeding newly-formed stars.
Aims. With the aim of further understanding the dynamics, chemistry, and
evolution of IRDCs, we carried out multi-wavelength observations on a small
sample.
Methods. We performed new observations with the IRAM 30 m and CSO 10.4 m
telescopes, with tracers , HCN, , ,
DCO, SiO, and DCN toward six IRDCs G031.97+00.07, G033.69-00.01,
G034.43+00.24, G035.39-00.33, G038.95-00.47, and G053.11+00.05.
Results. We investigated 44 cores including 37 cores reported in previous
work and seven newly-identified cores. Toward the dense cores, we detected 6
DCO, and 5 DCN lines. Using pixel-by-pixel spectral energy distribution
(SED) fits of the 70 to 500 m, we obtained dust
temperature and column density distributions of the IRDCs. We found that emission has a strong correlation with the dust temperature and column
density distributions, while showed the weakest correlation. It
is suggested that is indeed a good tracer in very dense
conditions, but is an unreliable one, as it has a relatively
low critical density and is vulnerable to freezing-out onto the surface of cold
dust grains. The dynamics within IRDCs are active, with infall, outflow, and
collapse; the spectra are abundant especially in deuterium species.
Conclusions. We observe many blueshifted and redshifted profiles,
respectively, with and toward the same core. This
case can be well explained by model "envelope expansion with core collapse
(EECC)".Comment: 24 pages, 11 figures, 4 tables. To be published in A&A. The
resolutions of the pictures are cut dow
Positive-partial-transpose distinguishability for lattice-type maximally entangled states
We study the distinguishability of a particular type of maximally entangled
states -- the "lattice states" using a new approach of semidefinite program.
With this, we successfully construct all sets of four ququad-ququad orthogonal
maximally entangled states that are locally indistinguishable and find some
curious sets of six states having interesting property of distinguishability.
Also, some of the problems arose from \cite{CosentinoR14} about the
PPT-distinguishability of "lattice" maximally entangled states can be answered.Comment: It's rewritten. We deleted the original section II about
PPT-distinguishability of three ququad-ququad MESs. Moreover, we have joined
new section V which discuss PPT-distinguishability of lattice MESs for cases
and . As a result, the sequence of the theorems in our article
has been changed. And we revised the title of our articl
2-(2-Hydroxy-3-methoxyphenyl)-1H-benzimidazol-3-ium perchlorate
In the title molecular salt, C14H13N2O2
+·ClO4
−, the ring systems in the cation are almost coplanar [dihedral angle = 5.53 (13)°]. Intramolecular N—H⋯O and O—H⋯O hydrogen bonds generate S(6) and S(5) rings, respectively. In the crystal, the two H atoms involved in the intramolecular hydrogen bonds also participate in intermolecular links to acceptor O atoms of the perchlorate anions. A simple intermolecular N—H⋯O bond also occurs. Together, these form a double-chain structure along [101]
Quantifying immediate price impact of trades based on the -shell decomposition of stock trading networks
Traders in a stock market exchange stock shares and form a stock trading
network. Trades at different positions of the stock trading network may contain
different information. We construct stock trading networks based on the limit
order book data and classify traders into classes using the -shell
decomposition method. We investigate the influences of trading behaviors on the
price impact by comparing a closed national market (A-shares) with an
international market (B-shares), individuals and institutions, partially filled
and filled trades, buyer-initiated and seller-initiated trades, and trades at
different positions of a trading network. Institutional traders professionally
use some trading strategies to reduce the price impact and individuals at the
same positions in the trading network have a higher price impact than
institutions. We also find that trades in the core have higher price impacts
than those in the peripheral shell.Comment: 6 pages including 3 figures and 1 tabl
Probing the initial conditions of high-mass star formation -- IV. Gas dynamics and NHD chemistry in high-mass precluster and protocluster clumps
The initial stage of star formation is a complex area study because of its
high density and low temperature. Under such conditions, many molecules become
depleted from the gas phase by freezing out onto dust grains. However, the
deuterated species could remain gaseous and are thus ideal tracers. We
investigate the gas dynamics and NHD chemistry in eight massive
pre/protocluster clumps. We present NHD 1-1 (at 85.926 GHz),
NH (1, 1) and (2, 2) observations in the eight clumps using the PdBI and
the VLA, respectively. We find that the distribution between deuterium
fractionation and kinetic temperature shows a number density peak at around
K, and the NHD cores are mainly located at a temperature
range of 13.0 to 22.0 K. We detect seven instances of extremely high deuterium
fractionation of . We find that the
NHD emission does not appear to coincide exactly with either dust continuum
or NH peak positions, but often surrounds the star-formation active
regions. This suggests that the NHD has been destroyed by the central
young stellar object (YSO) due to its heating. The detected NHD lines are
very narrow with a median width of . The extracted
NHD cores are gravitationally bound (), are likely
prestellar or starless, and can potentially form intermediate-mass or high-mass
stars. Using NH (1, 1) as a dynamical tracer, we find very complicated
dynamical movement, which can be explained by a combined process with outflow,
rotation, convergent flow, collision, large velocity gradient, and rotating
toroids. High deuterium fractionation strongly depends on the temperature
condition. NHD is a poor evolutionary indicator of high-mass star formation
in evolved stages, but a useful tracer in the starless and prestellar cores.Comment: 27 pages, 25 figures, 6 tables, accepted for publication in A&
miRNA-mRNA-protein dysregulated network in COPD in women
Rationale: Chronic obstructive pulmonary disease (COPD) is a complex disease caused by a multitude of underlying mechanisms, and molecular mechanistic modeling of COPD, especially at a multi-molecular level, is needed to facilitate the development of molecular diagnostic and prognostic tools and efficacious treatments.Objectives: To investigate the miRNA-mRNA-protein dysregulated network to facilitate prediction of biomarkers and disease subnetwork in COPD in women.Measurements and Results: Three omics data blocks (mRNA, miRNA, and protein) collected from BAL cells from female current-smoker COPD patients, smokers with normal lung function, and healthy never-smokers were integrated with miRNA-mRNA-protein regulatory networks to construct a COPD-specific dysregulated network. Furthermore, downstream network topology, literature annotation, and functional enrichment analysis identified both known and novel disease-related biomarkers and pathways. Both abnormal regulations in miRNA-induced mRNA transcription and protein translation repression play roles in COPD. Finally, the let-7-AIFM1-FKBP1A pathway is highlighted in COPD pathology.Conclusion: For the first time, a comprehensive miRNA-mRNA-protein dysregulated network of primary immune cells from the lung related to COPD in females was constructed to elucidate specific biomarkers and disease pathways. The multi-omics network provides a new molecular insight from a multi-molecular aspect and highlights dysregulated interactions. The highlighted let-7-AIFM1-FKBP1A pathway also indicates new hypotheses of COPD pathology.Peer reviewe
Ethyl 1-(4-methoxybenzyl)-3-p-tolyl-1H-pyrazole-5-carboxylate
In the title compound, C21H22N2O3, the pyrazole ring makes dihedral angles of 12.93 (8) and 69.38 (8)°, respectively, with the tolyl and methoxybenzyl rings
Effects of Bufei Yishen formula on klotho gene expression and inflammation-related RIG-I/NF-κB pathway in cigarette smoke extract-treated BEAS-2B cells
Purpose: To investigate the anti-inflammatory effect of Bufei yishen formula on chronic obstructive pulmonary disease (COPD) and klotho expression in cigarette smoke extract (CSE)-treated BEAS-2B cells.Methods: Cigarette smoke extract (CSE) was diluted in Dulbecco’s modified Eagle’s medium (DMEM) and used to treat a COPD cell model established using BEAS-2B cells. The CSE-treated cells were transfected with klotho overexpression plasmid, and the COPD cell model was treated with Bufei yishen formula. Dexamethasone was used as positive control. Changes in the expressions of klotho, RIG-I, and NF-ĸB were determined using reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting, while enzyme linked immunosorbent assay (ELISA) was used to evaluate changes in the expressions of IL-6 and TNF-α.Results: Klotho expression level was reduced in COPD model. Overexpression of klotho inhibited the expressions of IL-6, TNF-α, RIG-I, NF-κB, but bufei yishen formula increased klotho expression level and decreased the expressions of RIG-I, NF-κB, IL-6 and TNF-α. However, after CSE treatment, the anti-inflammatory effect of the formula decreased significantly when klotho expression was knocked down.Conclusion: Bufei yishen formula possesses anti-inflammatory effects which are significantly decreased after klotho knockdown. This suggests that the formula probably acts by upregulating klotho expression, thereby down-regulating the expressions of IL-6 and TNF-α via RIG-I/NF-κB pathway.Keywords: Bufei yishen formula, COPD, Klotho, Inflammation, RIG-I/NF-κ
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