We present here a detailed study of the oxidation resistance of chemical vapor deposition (CVD) graphene. The results reveal that CVD graphene shows an excellent performance as a passivation layer ...below 200°C, but the protection ability degenerates rapidly with increasing the air temperature. Our work demonstrates for the first time that the most adverse effect on the degeneration of oxidation resistance in high temperature air comes from wrinkles but not others, such as Cu grain boundaries, periodic surface depressions due to Cu surface reconstruction induced by the graphene overlay, graphene domain boundaries, which are always believed the primary factor for inferior quality of the CVD graphene at present. In addition, we found that the distribution of the wrinkles in CVD graphene depended on the Cu crystal structure, and the results of the Electron-backscatter diffraction indicate that the folded wrinkles always appear on Cu (001) facets, while the standing collapsed wrinkles appear more easily on the Cu (111) facets.
Purpose
To investigate the potential candidate microRNA (miRNA) biomarkers for the clinical diagnosis, classification, and prognosis of gastric cancer (GC).
Methods
We use bioinformatics overlapping ...subclasses analysis to find the tumor grade and lymphatic metastasis-related GC specific miRNAs from the Cancer Genome Atlas (TCGA) database. Then, we further investigated these GC specific miRNAs distributions in different GC clinical features and their correlations overall survival on the basis of GC patients’ information and their related RNA sequencing profile from TCGA. Finally, we randomly selected some of key miRNAs use qRT-PCR to confirm the reliability and validity.
Results
22 GC specific key miRNAs were identified (Fold-change >2,
P
< 0.05), 11 of them were discriminatively expressed with tumor size, grade, TNM stage and lymphatic metastasis (
P
< 0.05). In addition, nine miRNAs (miR-196b-5p, miR-135b-5p, miR-183-5p, miR-182-5p, miR-133a-3p, miR-486-5p, miR-144-5p, miR-129-5p and miR-145-5p) were found to be significantly associated with overall survival (log-rank
P
< 0.05). Finally, four key miRNAs (miR-183-5p, miR-486-5p, miR-30c-2-3p and miR-133a-3p) were randomly selected to validation and their expression levels in 53 newly diagnosed GC patients by qRT-PCR. Results showed that the fold-changes between TCGA and qRT-PCR were 100 % in agreement. We also found miR-183-5p and miR-486-5p were significantly correlated with tumor TNM stage (
P
< 0.05), and miR-30c-2-3p and miR-133a-3p were associated with tumor differentiation degree and lymph-node metastasis (
P
< 0.05). These verified miRNAs clinically relevant, and the bioinformatics analysis results were almost the same.
Conclusion
These key miRNAs may functions as potential candidate biomarkers for the clinical diagnosis, classification and prognosis for GC.
A
bstract
Using
e
+
e
−
annihilation data corresponding to a total integrated luminosity of 6
.
32 fb
−
1
collected at the center-of-mass energies between 4.178 and 4.226 GeV with the BESIII ...detector, we perform an amplitude analysis of the decay
D
s
+
→
K
−
K
+
π
+
π
+
π
−
and determine the relative fractions and phases of different intermediate processes. Absolute branching fraction of
D
s
+
→ K
−
K
+
π
+
π
+
π
−
decay is measured to be (6
.
60
±
0
.
47
stat
.
±
0
.
38
syst
.
)
×
10
−
3
. The dominant intermediate process is
D
s
+
→ a
1
(1260)
+
ϕ, ϕ → K
−
K
+
, a
1
(1260)
+
→ ρπ
+
, ρ → π
+
π
−
, with a branching fraction of (5
.
15
±
0
.
41
stat
.
±
0
.
32
syst
.
)
×
10
−
3
.
A
bstract
Using data collected with the BESIII detector in
e
+
e
−
collisions at center-of-mass energies between 4.178 and 4.226 GeV and corresponding to 6.32 fb
−
1
of integrated luminosity, we ...report the amplitude analysis and branching-fraction measurement of the
D
s
+
→ π
+
π
0
η
′ decay. We find that the dominant intermediate process is
D
s
+
→ ρ
+
η
′ and the significances of other resonant and nonresonant processes are all less than 3
σ
. The upper limits on the branching fractions of
S
-wave and
P
-wave nonresonant components are set to 0.10% and 0.74% at the 90% confidence level, respectively. In addition, the branching fraction of the
D
s
+
→ π
+
π
0
η
′ decay is measured to be (6
.
15
±
0
.
25(stat
.
)
±
0
.
18(syst
.
))%, which receives significant contribution only from
D
s
+
→ ρ
+
η
′ according to the amplitude analysis.
Search for the decay hc→ π0J/ψ Ban, Y.; Boyko, I.; Cai, X. ...
The journal of high energy physics,
05/2022, Letnik:
2022, Številka:
5
Journal Article
Recenzirano
Odprti dostop
A
bstract
A search for the decay
h
c
→ π
0
J/ψ
is performed using a sample of
hc
produced in the reaction
e
+
e
−
→ π
+
π
−
h
c
. The data samples were collected with the BESIII detector at ...center-of-mass energies between 4.189 and 4.437 GeV, corresponding to a total integrated luminosity of 11 fb
−
1
. No significant signal is observed. Upper limits on the branching ratio
B
(
h
c
→ π
0
J/ψ
)
/
B
(
h
c
→ γη
c
→ γK
+
K
−
π
0
) and on the branching fraction
B
(
h
c
→ π
0
J/ψ
) are determined to be 7
.
5
×
10
−
2
and 4
.
7
×
10
−
4
at 90% confidence level, respectively. The latter is derived from the former using the measured branching fraction of the normalization channel. This is the first determination of the upper limit of the decay
h
c
→ π
0
J/ψ
.
•Waterless cleaning process in this paper does not require any reagent.•Waterless cleaning Cu substrate can effectively reduce the nucleation density of graphene.•Waterless cleaning of Cu substrate ...is beneficial to reduce the cost of preparing graphene and reduce chemical pollution.
A waterless cleaning method of Cu foil for chemical vapor deposition (CVD) graphene growth is proposed in this work. In our method, the Cu foil is first annealed in high temperature air and then cooled rapidly, contaminated Cu surface layer was oxided in annealing and separated in the following cooling process, so as to get a clean Cu surface, the whole process does not require the participation of water and other reagents. Due to the influence of oxygen, the density of graphene domains on the waterless cleaning substrate is even lower than that on the polished substrate. Waterless cleaning provides a simple, economical and environment friendly.
KRAS mutations are the earliest events found in approximately 90% of pancreatic ductal adenocarcinomas (PDACs). However, little is known as to why KRAS mutations preferentially occur in PDACs and ...what processes/factors generate these mutations. While abnormal carbohydrate metabolism is associated with a high risk of pancreatic cancer, it remains elusive whether a direct relationship between KRAS mutations and sugar metabolism exists. Here, we show that under high-glucose conditions, cellular O-GlcNAcylation is significantly elevated in pancreatic cells that exhibit lower phosphofructokinase (PFK) activity than other cell types. This post-translational modification specifically compromises the ribonucleotide reductase (RNR) activity, leading to deficiency in dNTP pools, genomic DNA alterations with KRAS mutations, and cellular transformation. These results establish a mechanistic link between a perturbed sugar metabolism and genomic instability that induces de novo oncogenic KRAS mutations preferentially in pancreatic cells.
Display omitted
•Pancreatic cells exhibit lower phosphofructokinase activity than other cell types•High glucose elevates O-GlcNAcylation and genomic alterations in pancreatic cells•Reduction of RNR activity leads to nucleotide pool imbalance and KRAS mutations•PFK activity alters the sensitivity to high-glucose-induced genomic effects
Most pancreatic ductal adenocarcinomas contain activated KRAS mutations required for cancer initiation and maintenance. Here, Hu et al. show that high glucose promotes O-GlcNAcylation on ribonucleotide reductase, leading to nucleotide pool imbalance and KRAS mutations preferentially in pancreatic cells.
•The dynamic features of laser-induced cavitation bubble are investigated.•Wall-leaning effect of cavitation bubble is proved.•The relations between relative distance parameter γ and strengthening ...mechanism of cavitation bubble are discussed.•A new strengthening method based on laser-induced cavitation shotless peening (CSP) is provided.
The dynamic features of nanosecond laser-induced cavitation bubbles near the light alloy boundary were investigated with the high-speed photography. The shock-waves and the dynamic characteristics of the cavitation bubbles generated by the laser were detected using the hydrophone. The dynamic features and strengthening mechanism of cavitation bubbles were studied. The strengthening mechanisms of cavitation bubble were discussed when the relative distance parameter γ was within the range of 0.5–2.5. It showed that the strengthening mechanisms caused by liquid jet or shock-waves depended on γ much. The research results provided a new strengthening method based on laser-induced cavitation shotless peening (CSP).
This study investigated the influence of the copper substrate surface fluctuations on the transfer of graphene fabricated via chemical vapor deposition. Typical fluctuations, such as reconstructed ...stripes, grain boundaries, and mechanical creases on Cu surface were explored. The upper graphene which have consistent morphology with the fluctuations were not incompletely copied into the target but by rearrangement after the transfer process. Moreover, some fluctuations may induce damage or glue residual formation in the transfer process.
•The effects of the Cu surface fluctuations on the graphene transfer were studied.•The graphene was redistributed rather than directly copied to the target substrate during the transfer.•The fluctuations on the Cu surface may induce the residual of PMMA and damage in the transfer.
Trypsin proteinases perform important roles in the protein digestion of an insect midgut. A 1042 bp full-length cDNA was cloned from Helicoverpa armigera. The gene encoded a 32 kDa protein, with a ...predicted isoelectric point of 5.7. The amino acid sequence of the protein had a trypsin-like serine protease domain, and the gene was named Ha-TLP. The expression of the gene was tissue-specific and the transcript of Ha-TLP existed only in the midgut and was not found in the head-thorax, integument, fat body and haemocytes from 5th instar larvae, with similar expression levels between those in feeding larvae and in molting larvae. In the midgut, the gene transcription level declined from 6th instar 72 h after the larvae entered the wandering stage, and disappeared from 6th instar at 96 h until the pupal stage. By immunohistochemistry, Ha-TLP was detected in the cytoplasm of the midgut epithelial cells of the 6th instar feeding stage worms. The expression of Ha-TLP could be up-regulated by a juvenile hormone (JH) analog methoprene and down-regulated by 20-hydroxyecdysone (20E). These facts indicate that Ha-TLP was involved in food digestion during larval growth and probably up-regulated by JH and suppressed by extra 20E in vivo.
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