135 research outputs found
CO Emission Delineating the Interface between the Milky Way Nuclear Wind Cavity and the Gaseous Disk
Based on the MWISP survey, we study high-z CO emission toward the tangent
points, in which the distances of the molecular clouds (MCs) are well
determined. In the region of l=12-26 deg and |b|<5.1 deg, a total of 321 MCs
with |z|> 110 pc are identified, of which nearly 30 extreme high-z MCs (EHMCs
at |z|> 260 pc) are concentrated in a narrow region of R_GC=2.6-3.1 kpc. The
EHMC concentrations, together with other high-z MCs at R_GC=2.3-2.6 kpc,
constitute molecular crater-wall structures surrounding the edges of the HI
voids that are physically associated with the Fermi bubbles. Intriguingly, some
large high-z MCs, which lie in the crater-walls above and below the Galactic
plane, show cometary structures with the head toward the plane, favouring the
scenario that the entrained molecular gas moves with the multi-phase flows from
the plane to the high-z regions. We suggest that the Milky Way nuclear wind has
a significant impact on the Galactic gaseous disk. The powerful nuclear wind at
~3-6 Myr ago is likely responsible for the observational features, (1) the
enhanced CO gas lying in the edges of the HI voids, (2) the deficiency of
atomic and molecular gas within R_GC<3 kpc, (3) the possible connection between
the EHMC concentrations and the 3-kpc arm, and (4) the elongated high-z MCs
with the tail pointing away from the Galactic plane.Comment: 27 pages, 7 Figures, 1 Table. To appear in ApJ. Comments are welcome
Understanding the Kinetic Energy deposition within Molecular Clouds
According to the structures traced by CO spectral lines within the
CO molecular clouds (MCs), we investigate the contributions of their
internal gas motions and relative motions to the total velocity dispersions of
CO MCs. Our samples of 2851 CO MCs harbor a total of 9556
individual CO structures, among which 1848 MCs ( 65) have one
individual CO structure and the other 1003 MCs ( 35) have
multiple CO structures. We find that the contribution of the relative
motion between CO structures () is larger than
that from their internal gas motion () in
62 of 1003 MCs in the `multiple' regime. In addition, we find the
tends to increase with the total velocity
dispersion() in our samples, especially for the MCs
having multiple CO structures. This result provides a manifestation of
the macro-turbulent within MCs, which gradually becomes the dominant way to
store the kinetic energy along with the development of MC scales.Comment: 15 pages, 13 figures, accepted for publication in Ap
Relative velocities between CO structures within CO Molecular clouds
Velocity fields of molecular clouds (MCs) can provide crucial information on
the merger and split between clouds, as well as their internal kinematics and
maintenance, energy injection and redistribution, even star formation within
clouds. Using the CO spectral lines data from the Milky Way Imaging Scroll
Painting (MWISP) survey, we measure the relative velocities along the line of
sight (V) between CO structures within CO
MCs. Emphasizing MCs with double and triple CO structures, we find that
approximately 70 of V values are less than 1 km
s, and roughly 10 of values exceed 2 km s, with a maximum of
5 km s. Additionally, we compare V with the
internal velocity dispersion of CO structures () and find that about 40 of samples in either double or triple
regime display distinct velocity discontinuities, i.e. the relative velocities
between CO structures are larger than the internal linewidths of
CO structures. Among these 40 samples in the triple regime, 33
exhibit signatures of combinations through the two-body motion, whereas the
remaining 7 show features of configurations through the multiple-body
motion. The V distributions for MCs with double and triple
CO structures are similar, as well as their V/ distributions. This suggests that relative
motions of CO structures within MCs are random and independent of cloud
complexities and scales.Comment: 16 pages, 11 figures, accepted for publication in A
A Systematic Study of Associations between Supernova Remnants and Molecular Clouds
We universally search for evidence of kinematic and spatial correlation of
supernova remnant (SNR) and molecular cloud (MC) associations for nearly all
SNRs in the coverage of the MWISP CO survey, i.e. 149 SNRs, 170 SNR candidates,
and 18 pure pulsar wind nebulae (PWNe) in 1 deg < l < 230 deg and -5.5 deg < b
< 5.5 deg. Based on high-quality and unbiased 12CO/13CO/C18O (J = 1--0) survey
data, we apply automatic algorithms to identify broad lines and spatial
correlations for molecular gas in each SNR region. The 91% of SNR-MC
associations detected previously are identified in this paper by CO line
emission. Overall, there could be as high as 80% of SNRs associated with MCs.
The proportion of SNRs associated with MCs is high within the Galactic
longitude less than ~50 deg. Kinematic distances of all SNRs that are
associated with MCs are estimated based on systemic velocities of associated
MCs. The radius of SNRs associated with MCs follows a lognormal distribution,
which peaks at ~8.1 pc. The progenitor initial mass of these SNRs follows a
power-law distribution with an index of ~-2.3 that is consistent with the
Salpeter index of -2.35. We find that SNR-MC associations are mainly
distributed in a thin disk along the Galactic plane, while a small amount
distributed in a thick disk. With the height of these SNRs from the Galactic
plane below ~45 pc, the distribution of the average radius relative to the
height of them is roughly flat, and the average radius increases with the
height when above ~45 pc.Comment: 77 pages, 20 figures, 4 tables (with machine-readable versions),
accepted for publication in ApJ
Effect of Cu doping on the microstructure and mechanical properties of AlTiVN-Cu nanocomposite coatings
Cu phase has been incorporated into hard coatings to form nanocomposite structure, which not only enhanced the hardness but also the toughness due to excellent ductility of copper. In this study, a single Al67Ti33-V-Cu spliced target was used to prepare the AlTiVN-Cu nanocomposite coatings, and the effect of Cu doping on microstructure and mechanical properties of AlTiVN-Cu coatings has been investigated. The results showed that the deposition rate linearly increased from 3.8 to 13.4 nm/min when Cu content increased from 2.6 to 46.7 at.%. AlTiVN-Cu coatings exhibited a Ti-Al-V-N solid-solution phase with strong (111) preferred orientation at low Cu contents below 8.3 at.%. When Cu content increased above 22.6 at.%, Cu atoms grew up into metallic crystallites and strongly suppressed crystal growth of nitride coatings due to repeated nucleation. With increasing Cu content, the microstructure transferred from compact columnar to dense featureless, and then to coarse columnar structure. AlTiVN-Cu(2.6 at.%) coating exhibited a super hardness of 41.1 GPa and an excellent toughness with a high H3/E*2 ratio of 0.24
Synthesis of Icariin-Zinc and its Protective Effect on Exercise Fatigue and Reproductive System Related Glands in Male Rats
Background: Icariin, a traditional Chinese medicine, plays a protective role in the treatment of exercise fatigue. Zinc, a trace element, plays an important role in the reproductive system. Therefore, we aimed to synthesize an Icariin-Zinc complex (by chemical means) and verify its protective effect on exercise fatigue and the reproductive system using animal experiments.Methods: The icariin-zinc complex was prepared by the reaction of icariin carbonyl and zinc ions (molar ratio 1:3). The molecular formula and structural formula of the complex were identified and tested. Fifty-six rats selected by swimming training were randomly divided into six groups: static control, exercise control, icariin, gluconate zinc (G-Zn group), icariin glucose zinc and icariin-zinc exercise ( low, high dose/L-E group, H-E group) groups. These groups respectively received the following doses: 1Â ml/100Â g, daily gavage with NS (for the first two groups), 45Â mg/kg icariin, 110Â mg/kg Gluconate Zinc, Icariin glucose zinc (45Â mg/kg Icariin and 110Â mg/kg Gluconate Zinc), 60Â mg/kg icariin zinc and 180Â mg/kg icariin zinc. After 3Â weeks of gavage, we conducted 6Â weeks of exhaustive swimming training. Test indices such as exhaustive swimming time of rats and body weight were evaluated after the last training exercise. The seminal vesicles, testes, and prostate gland were weighed, and their indices were calculated. The levels of testosterone (in the plasma) and glycogen (in the liver and muscle homogenates) were also evaluated using ELISA.Results: Compared with the static control group, the exhaustive swimming time of the rats in each group was prolonged. Compared with the other groups, the exhaustive swimming time of the L-E and H-E groups was significantly longer (p < 0.01); the Icariin-Zinc complex significantly increased the exhaustive swimming time of the rats. Compared with the static control group, the plasma testosterone content of the L-E and H-E groups increased significantly (p < 0.05). Compared with the exercise control group and G-Zn group, the plasma testosterone content of the H-E group also increased significantly (p < 0.01). The Icariin-Zinc complex significantly increased the serum levels of testosterone in rats. Compared with the control group, the muscle glycogen reserves of each group decreased, indicating that the muscle glycogen reserves of the rats decreased after swimming. Compared with other groups, the Icariin-Zinc complex can reduce the level of glycogen in the muscles, indicating that it can increase the utilization efficiency of glycogen in muscles. Compared with the static control and exercise control groups, the testicular weight of rats in the administration groups increased slightly. The Icariin-Zinc complex increased the testicular weight, indicating that the function of the reproductive system was improved to some extent.Conclusion: Icariin-Zinc can significantly prolong the exhaustive swimming time, improve exercise ability, and increase the plasma testosterone level (which is beneficial for improving the reproductive ability of male rats). Moreover, the beneficial effect of Icariin-Zinc on the glycogen content, testis index, and other reproductive system glands is dose-dependent
A pan-cancer proteomic perspective on The Cancer Genome Atlas.
Protein levels and function are poorly predicted by genomic and transcriptomic analysis of patient tumours. Therefore, direct study of the functional proteome has the potential to provide a wealth of information that complements and extends genomic, epigenomic and transcriptomic analysis in The Cancer Genome Atlas (TCGA) projects. Here we use reverse-phase protein arrays to analyse 3,467 patient samples from 11 TCGA 'Pan-Cancer' diseases, using 181 high-quality antibodies that target 128 total proteins and 53 post-translationally modified proteins. The resultant proteomic data are integrated with genomic and transcriptomic analyses of the same samples to identify commonalities, differences, emergent pathways and network biology within and across tumour lineages. In addition, tissue-specific signals are reduced computationally to enhance biomarker and target discovery spanning multiple tumour lineages. This integrative analysis, with an emphasis on pathways and potentially actionable proteins, provides a framework for determining the prognostic, predictive and therapeutic relevance of the functional proteome
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