110 research outputs found
Digital Transformation of High Voltage Isolation Control and Monitoring System for HVE-400 Ion Implanter
HVE-400 ion implanter is special ion implantation equipment for semiconductor
materials boron and phosphorus doping. The ion source and extraction deflection
system are at high voltage platform, while the corresponding control system is
at ground voltage position. The control signals and measurement signals of
various parameters at the high-voltage end need to be transmitted between
ground voltage and high voltage through optical fibers to isolate high voltage.
Upgrading is carried out due to the aging of the optical fiber transmission
control and monitoring system, which cannot work stably. The transformation
replaces the original distributed single-point control method with an advanced
distributed centralized control method, and integrates all control and
monitoring functions into an industrial control computer for digital operation
and display. In the computer software, two kinds of automatic calculation of
ion mass number are designed. After upgrading, the implanter high-voltage
platform control and monitoring system features digitalization, centralized
control, high reliability, strong anti-interference, fast communication speed,
and easy operation.Comment: 6 pages, 4 figures, 1 tabl
Relationship Between Dairy Products Intake and Risk of Endometriosis: A Systematic Review and Dose-Response Meta-Analysis
Objective: Diet lifestyle can influence the risk of endometriosis. Therefore, we conducted
a systematicmeta-analysis to investigate the association between dairy products and the
risk of endometriosis. Besides, we performed a dose-responsemeta-analysis to evaluate
the amount of dairy intake affecting the risk of endometriosis.
Methods: Relevant studies were searched from Pubmed, Embase databases,
Cochrane Library, and Web of Science from the inception to November 6th, 2020. Also,
the dose-response meta-analysis was conducted. All the pooled results were performed
by risk ratios (RRs).
Results: Finally, seven high-quality studies were included in the present meta-analysis.
Total dairy intake was inversely associated with the risk of endometriosis, and the
risk of endometriosis tended to decrease with a decrease in the risk of endometriosis
when dairy products intake was over 21 servings/week (RR 0.87, 95% CI 0.76–1.00;
pnon−linearity = 0.04). Similarly, people who consumed more than 18 servings of high-fat
dairy products per week had a reduced risk of endometriosis (RR 0.86, 95% CI
0.76–0.96). When stratified-analyses were conducted based on specific dairy product
categories, it indicated that people with high cheese intake might have a reduced risk of
endometriosis (RR 0.86, 95%CI 0.74–1.00). Other specific dairy products such as whole
milk (RR 0.90, 95% CI 0.72–1.12), reduced-fat/skim milk (RR 0.83, 95% CI 0.50–1.73),
ice cream (RR 0.83, 95% CI 0.50–1.73), and yogurt (RR 0.83, 95% CI 0.62–1.11) have
not shown significant evidence of an association with the risk of endometriosis. However,
there is a higher risk of endometriosis in the females with high butter intake compared to
females with low butter intake (1.27, 95% CI 1.03–1.55).
Conclusions: Overall, dairy products intake was associated with a reduction in
endometriosis, with significant effects when the average daily intake 3 servings. When
analyzed according to the specific type of dairy product, it was shown that females with
higher high-fat dairy and cheese intake might have a reduced risk of endometriosis.
However, high butter intake might be associated to the increased risk of endometriosis.
More future studies are needed to validate and add to this finding
CO (J = 1–0) Observations toward Filamentary Molecular Clouds in the Galactic Region with l = [169.°75, 174.°75], b = [−0.°75, 0.°5]
We present observations of the CO isotopologues (12CO, 13CO, and C18O) toward the Galactic region with 169fdg75 ≤ l ≤ 174fdg75 and −0fdg75 ≤ b ≤ 0fdg5 using the Purple Mountain Observatory 13.7 m millimeter-wavelength telescope. Based on the 13CO (J = 1 − 0) data, we find five molecular clouds within the velocity range between −25 and 8 km s−1 that are all characterized by conspicuous filamentary structures. We have identified eight filaments with a length of 6.38–28.45 pc, a mean H2 column density of 0.70 × 1021–6.53 × 1021 cm−2, and a line mass of 20.24–161.91 M ☉ pc−1, assuming a distance of ~1.7 kpc. Gaussian fittings to the inner parts of the radial density profiles lead to a mean FWHM width of 1.13 ± 0.01 pc. The velocity structures of most filaments present continuous distributions with slight velocity gradients. We find that turbulence is the dominant internal pressure to support the fragmentation of filaments instead of thermal pressure. Most filaments have virial parameters smaller than 2; thus, they are gravitationally bound. Four filaments have an LTE line mass close to the virial line mass. We further extract dense clumps using the 13CO data and find that 64% of the clumps are associated with the filaments. According to the complementary IR data, most filaments have associated Class II young stellar objects. Class I objects are mainly found to be located in the filaments with a virial parameter close to 1. Within two virialized filaments, 12CO outflows have been detected, indicating ongoing star-forming activity therein.National Key Research & Development of China [2017YFA0402702]; European Unions Horizon 2020 research and innovation program [639459]; NSFC [11473069, 11503086, 11629302]This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Exogenous treatment with melatonin enhances waterlogging tolerance of kiwifruit plants
Waterlogging stress has an enormous negative impact on the kiwifruit yield and quality. The protective role of exogenous melatonin on water stress has been widely studied, especially in drought stress. However, the research on melatonin-induced waterlogging tolerance is scarce. Here, we found that treatment with exogenous melatonin could effectively alleviate the damage on kiwifruit plants in response to waterlogging treatment. This was accompanied by higher antioxidant activity and lower ROS accumulation in kiwifruit roots during stress period. The detection of changes in amino acid levels of kiwifruit roots during waterlogging stress showed a possible interaction between melatonin and amino acid metabolism, which promoted the tolerance of kiwifruit plants to waterlogging. The higher levels of GABA and Pro in the roots of melatonin-treated kiwifruit plants partly contributed to their improved waterlogging tolerance. In addition, some plant hormones were also involved in the melatonin-mediated waterlogging tolerance, such as the enhancement of ACC accumulation. This study discussed the melatonin-mediated water stress tolerance of plants from the perspective of amino acid metabolism for the first time
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
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
The Cassiopeia Filament: A Blown Spur of the Local Arm
We present wide-field and high-sensitivity CO(1-0) molecular line
observations toward the Cassiopeia region, using the 13.7m millimeter telescope
of the Purple Mountain Observatory (PMO). The CO observations reveal a
large-scale highly filamentary molecular cloud within the Galactic region of
132\fdg0\,\,\,\,122\fdg0 and
-1\fdg0\,\,\,\,3\fdg0 and the velocity range from approximately
+1 to +4 km/s. The measured length of the large-scale filament, referred to as
the Cassiopeia Filament, is about 390 pc. The observed properties of the
Cassiopeia Filament, such as length, column density, and velocity gradient, are
consistent with those synthetic large-scale filaments in the inter-arm regions.
Based on its observed properties and location on the Galactic plane, we suggest
that the Cassiopeia Filament is a spur of the Local arm, which is formed due to
the galactic shear. The western end of the Cassiopeia Filament shows a giant
arc-like molecular gas shell, which is extending in the velocity range from
roughly -1 to +7 km/s. Finger-like structures, with systematic velocity
gradients, are detected in the shell. The CO kinematics suggest that the large
shell is expanding at a velocity of ~6.5 km/s. Both the shell and finger-like
structures outline a giant bubble with a radius of ~16 pc, which is likely
produced by stellar wind from the progenitor star of a supernova remnant. The
observed spectral linewidths suggest that the whole Cassiopeia Filament was
quiescent initially until its west part was blown by stellar wind and became
supersonically turbulent.Comment: 46 pages, 19 figures, to be published by the A
- …