A
bstract
Based on 4.5 fb
−
1
data taken at seven center-of-mass energies ranging from 4.600 to 4.699 GeV with the BESIII detector at the BEPCII collider, we measure the branching fractions of
$$ ...{\Lambda}_c^{+} $$
Λ
c
+
→
Σ
+
+
hadrons
relative to
$$ {\Lambda}_c^{+} $$
Λ
c
+
→
Σ
+
π
+
π
−
. Combining with the world average branching fraction of
$$ {\Lambda}_c^{+} $$
Λ
c
+
→
Σ
+
π
+
π
−
, their branching fractions are measured to be (0
.
377
±
0
.
042
±
0
.
020
±
0
.
021)% for
$$ {\Lambda}_c^{+} $$
Λ
c
+
→
Σ
+
K
+
K
−
, (0
.
200
±
0
.
023
±
0
.
011
±
0
.
011)% for
$$ {\Lambda}_c^{+} $$
Λ
c
+
→
Σ
+
K
+
π
−
, (0
.
414
±
0
.
080
±
0
.
030
±
0
.
023)% for
$$ {\Lambda}_c^{+} $$
Λ
c
+
→
Σ
+
ϕ
and (0
.
197
±
0
.
036
±
0
.
009
±
0
.
011)% for
$$ {\Lambda}_c^{+} $$
Λ
c
+
→ Σ
+
K
+
K
−
(non-
ϕ
). In all the above results, the first uncertainties are statistical, the second are systematic and the third are from external input of the branching fraction of
$$ {\Lambda}_c^{+} $$
Λ
c
+
→
Σ
+
π
+
π
−
. Since no signal for
$$ {\Lambda}_c^{+} $$
Λ
c
+
→
Σ
+
K
+
π
−
π
0
is observed, the upper limit of its branching fraction is determined to be 0.13% at the 90% confidence level.
This meta-analytic review aimed to examine the pooled prevalence rates of Internet addiction and gaming disorders in Southeast Asia. Several databases including PubMed, MEDLINE, PsycINFO, Web of ...Science, Embase, and Cochrane Central were searched and a total of 24 studies were included in this study. The selection of studies was conducted in accordance to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Two meta-analyses were conducted to examine data on Internet addiction and gaming disorders separately. A random-effects model was employed to derive the pooled prevalence rate. Mixed-effects meta-regression and subgroup analyses were performed to examine the moderators of the between-study heterogeneity. Publication bias was tested using the Egger's regression test and funnel plot. Only seven out of the 11 Southeast Asian countries were represented in the literature. All except for two of the included studies were cross-sectional in nature. The findings revealed a pooled prevalence rate of 20.0% (95% confidence interval: 14.5%-27.0%) and 10.1% (95% confidence interval: 7.3%-13.8%) for Internet addiction and gaming disorders respectively. Mean age and study population were significant moderators of the between-study heterogeneity in the prevalence rates of gaming disorders such that samples involving older participants showed higher prevalence rate than those involving younger individuals. Country of study was found to be significant moderator of the between-heterogeneity for both Internet addiction and gaming disorders, however the findings should be interpreted with caution due to the small and unbalanced sample sizes. There was no significant publication bias. Such epidemiology research should be extended to the Southeast Asian countries that have not been studied or are under-studied. Given that the prevalence rates appear to be higher in Southeast Asia than in other world regions, future research should also explore the factors behind these inter-regional differences. Further longitudinal studies should also be conducted to examine the trajectories of such disorders.
This work utilizes frustrated Lewis pairs consisting of tethered bis‐organophosphorus superbases and a bulky organoaluminum to furnish the highly efficient synthesis of well‐defined triblock ...copolymers via one‐step block copolymerization of lignin‐based syringyl methacrylate and n‐butyl acrylate, through di‐initiation and compounded sequence control. The resulting thermoplastic elastomers (TPEs) exhibit microphase separation and much superior mechanical properties (elongation at break up to 2091 %, tensile strength up to 11.5 MPa, and elastic recovery up to 95 % after 10 cycles) to those of methyl methacrylate‐based TPEs. More impressively, lignin‐based tri‐BCPs can maintain TPEs properties up to 180 °C, exhibit high transparency and nearly 100 % UV shield, suggesting potential applications in temperature‐resistant and optical devices.
Di‐initiating frustrated Lewis pairs promoted compounded sequence control to achieve one‐step synthesis of the well‐defined triblock copolymers. The resulting thermoplastic elastomers (TPEs) exhibit much superior mechanical properties to those of methyl methacrylate‐based TPEs and maintain TPEs properties at temperatures as high as 180 °C.
A
bstract
With data samples collected with the BESIII detector at seven energy points at
s
= 3
.
68
−
3
.
71 GeV, corresponding to an integrated luminosity of 333 pb
−
1
, we present a study of the Λ ...transverse polarization in the
e
+
e
−
→
Λ
Λ
¯
reaction. The significance of polarization by combining the seven energy points is found to be 2.6
σ
including the systematic uncertainty, which implies a non-zero phase between the transition amplitudes of the
Λ
Λ
¯
helicity states. The modulus ratio and the relative phase of EM-
psionic
form factors combined with all energy points are measured to be
R
Ψ
=
0.71
−
0.10
+
0.10
±
0.03 and ∆Φ
Ψ
=
23
−
8.0
+
8.8
±
1.6
°
, where the first uncertainties are statistical and the second systematic.
Abstract
This study was to investigate the effect of resveratrol on intestinal morphology, microfloras, and barrier integrity of broilers subjected to heat stress. Two-hundred-seventy 21-day-old Cobb ...male broilers were randomly allocated to 3 treatment groups, each of which included 6 replicates with 15 birds per replicate. The 3 treatment groups were as follows: the control group, in which birds were exposed to thermoneutral condition (22 ± 1°C), and the heat stress group and heat stress + resveratrol (400 mg/kg) group, in which birds were exposed to cyclic heat stress (33 ± 1°C for 10 h/d from 0800 to 1800 h and 22 ± 1°C for the remaining time. Compared with birds in the control group, birds in the heat stress group exhibited decreased (P < 0.05) final body weight, average daily gain, average daily feed intake, villus height, villus height to crypt depth ratio, goblet cells numbers, populations of Lactobacillus and Bifidobacterium, and mRNA levels of mucin-2, claudin-1, occludin, zona occludens-1, and E-cadherin, and increased (P < 0.05) crypt depth, serum D-lactic acid and fluorescein isothiocyanate dextran contents and diamine oxidase activity, and populations of Salmonella, Escherichia coli, and Clostridium. Compared with birds in the heat stress group, birds in the heat stress + resveratrol group exhibited decreased (P < 0.05) crypt depth, serum D-lactic acid and fluorescein isothiocyanate dextran contents, and populations of Escherichia coli, and increased (P < 0.05) final body weight, villus height, villus height to crypt depth ratio, goblet cells numbers, populations of Lactobacillus and Bifidobacterium, and mRNA levels of mucin-2, claudin-1, occludin, and E-cadherin. Taken together, these results indicated for the first time that dietary addition of resveratrol was effective in partially ameliorating the adverse effects of heat stress on intestinal barrier function in broilers by restoring the impaired villus-crypt structure, modifying the profiles of intestinal microfloras, and altering the mRNA expression of intestinal tight junctions- and adherence junctions-related genes.
A
bstract
We measure the branching fractions for seven
D
s
+
two-body decays to pseudo-scalar mesons, by analyzing data collected at
s
= 4
.
178 ∼ 4
.
226 GeV with the BESIII detector at the BEPCII ...collider. The branching fractions are determined to be
B
D
s
+
→
K
+
η
'
=
2.68
±
0.17
±
0.17
±
0.08
×
10
−
3
,
B
D
s
+
→
η
'
π
+
=
37.8
±
0.4
±
2.1
±
1.2
×
10
−
3
,
B
D
s
+
→
K
+
η
=
1.62
±
0.10
±
0.03
±
0.05
×
10
−
3
,
B
D
s
+
→
η
π
+
=
17.41
±
0.18
±
0.27
±
0.54
×
10
−
3
,
B
D
s
+
→
K
+
K
S
0
=
15.02
±
0.10
±
0.27
±
0.47
×
10
−
3
,
B
D
s
+
→
K
S
0
π
+
=
1.109
±
0.034
±
0.023
±
0.035
×
10
−
3
,
B
D
s
+
→
K
+
π
0
=
0.748
±
0.049
±
0.018
±
0.035
×
10
−
3
,
where the first uncertainties are statistical, the second are systematic, and the third are from external input branching fraction of the normalization mode
D
s
+
→
K
+
K
−
π
+
. Precision of our measurements is significantly improved compared with that of the current world average values.
Using a data sample with an integrated luminosity of 2.93 fb−1 taken at the center-of-mass energy of 3.773 GeV, we search for the Majorana neutrino (νm) in the lepton number violating decays ...D→Kπe+e+. No significant signal is observed, and the upper limits on the branching fraction at the 90% confidence level are set to be B(D0→K−π−e+e+)<2.8×10−6, B(D+→KS0π−e+e+)<3.3×10−6 and B(D+→K−π0e+e+)<8.5×10−6. The Majorana neutrino is searched for with different mass assumptions ranging from 0.25 to 1.0 GeV/c2 in the decays D0→K−e+νm,νm→π−e+ and D+→KS0e+νm,νm→π−e+, and the upper limits on the branching fraction at the 90% confidence level are at the level of 10−7 ~ 10−6, depending on the mass of the Majorana neutrino. The constraints on the mixing matrix element |Veνm|2 are also evaluated.
The glycolysis of poly(ethylene terephthalate) (PET) was studied using several ionic liquids and basic ionic liquids as catalysts. The basic ionic liquid, 1-butyl-3-methylimidazolium hydroxyl ...(BmimOH), exhibits higher catalytic activity for the glycolysis of PET, compared with 1-butyl-3-methylimidazolium bicarbonate (BmimHCO3), 1-butyl-3-methylimidazolium chloride (BmimCl) and 1-butyl-3-methylimidazolium bromide (BmimBr). FT-IR, 1H NMR and DSC were used to confirm the main product of glycolysis was bis(2-hydroxyethyl) terephthalate (BHET) monomer. The influences of experimental parameters, such as the amount of catalyst, glycolysis time, reaction temperature, and dosages of ethylene glycol on the conversion of PET, yield of BHET were investigated. The results showed a strong influence of the mixture evolution of temperature and reaction time on depolymerization of PET. Under the optimum conditions of m(PET):m(EG): 1:10, dosage of BmimOH at 0.1g (5wt%), reaction temperature 190°C and time 2h, the conversion of PET and the yield of BHET were 100% and 71.2% respectively. Balance between the polymerization of BHET and depolymerization of PET could be changed when the reaction time was more than 2h and contents of catalyst and EG were changed.
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