The cross section of the process e+e– → ωχc0 is measured at center-of-mass energies from √s = 4.178 to 4.278 GeV using a data sample of 7 fb–1 collected with the BESIII detector operating at the ...BEPCII storage ring. The dependence of the cross section on √s shows a resonant structure with mass of (4218.5 ± 1.6(stat) ± 4.0(syst)) MeV/c2 and width of (28.2 ± 3.9(stat) ± 1.6(syst)) MeV, respectively. This observation confirms and improves upon the result of a previous study. The angular distribution of the e+e– → ωχc0 process is extracted for the first time.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Fast and efficient: A library of trans‐cyclooctene (TCO)‐modified small molecules were immobilized on tetrazine‐functionalized glass slides by using the fastest bioorthogonal reaction known. The ...resulting small‐molecule microarray was screened against a variety of human bromodomains to identify protein–protein interaction inhibitors.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Using a data sample of 448.1×106 ψ(3686) events collected at s=3.686 GeV with the BESIII detector at the Beijing Electron-Positron Collider II, we search for the rare decay J/ψ→ϕe+e− via ...ψ(3686)→π+π−J/ψ. No signal events are observed and the upper limit on the branching fraction is set to be B(J/ψ→ϕe+e−)<1.2×10−7 at the 90% confidence level, which is still about one order of magnitude higher than the Standard Model prediction.
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Using data samples collected by the BESIII detector operating at the BEPCII storage ring, we measure the e+e– → KS0K±π∓ Born cross sections at center-of-mass energies between 3.8 and 4.6 GeV, ...corresponding to a luminosity of about 5.0 fb–1. The results are compatible with the BABAR measurements, but with the precision significantly improved. A simple 1/sn dependence for the continuum process can describe the measured cross sections, but a better fit is obtained by an additional resonance near 4.2 GeV, which could be an excited charmonium or a charmoniumlike state.
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We report the observation of W -annihilation decay Ds+ → ωπ+ and evidence for Ds+ → ωK+ in a data sample corresponding to an integrated luminosity of 3.19 fb–1 collected with the BESIII detector at a ...center-of-mass energy √s = 4.178 GeV. We obtain the branching fractions B( Ds+ → ωπ+ ) = (1.77 ± 0.32stat ± 0.13sys) ×10–3 with a significance of 6.7σ and B( Ds+ → ωK+ ) = (0.87 ± 0.24stat ± 0.08sys) ×10–3 with a significance of 4.4σ. This measurement provides critical information to determine the nonperturbative W -annihilation amplitudes and shows the potential of searching for CP asymmetry in Ds+ → ωK+ .
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The Born cross section for the process e+e– → p p ¯ is measured using the initial state radiation technique with an undetected photon. This analysis is based on datasets corresponding to an ...integrated luminosity of 7.5 fb–1, collected with the BESIII detector at the BEPCII collider at center of mass energies between 3.773 and 4.600 GeV. The Born cross section for the process e+e– → p p ¯ and the proton effective form factor are determined in the p ¯p invariant mass range between 2.0 and 3.8 GeV/c2 divided into 30 intervals. The proton form factor ratio (|GE|/|GM|) is measured in 3 intervals of the p¯p invariant mass between 2.0 and 3.0 GeV/c2.
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FOXO3a is a transcription factor of the FOXO family. The FOXO proteins participate in multiple signaling pathways, and their transcriptional activity is regulated by several post-translational ...mechanisms, including phosphorylation, acetylation and ubiquitination. Because these post-translational modification sites are located within the C-terminal basic region of the FOXO DNA-binding domain (FOXO-DBD), it is possible that these post-translational modifications could alter the DNA-binding characteristics. To understand how FOXO mediate transcriptional activity, we report here the 2.7 Å crystal structure of the DNA-binding domain of FOXO3a (FOXO3a-DBD) bound to a 13-bp DNA duplex containing a FOXO consensus binding sequence (GTAAACA). Based on a unique structural feature in the C-terminal region and results from biochemical and mutational studies, our studies may explain how FOXO-DBD C-terminal phosphorylation by protein kinase B (PKB) or acetylation by cAMP-response element binding protein (CBP) can attenuate the DNA-binding activity and thereby reduce transcriptional activity of FOXO proteins. In addition, we demonstrate that the methyl groups of specific thymine bases within the consensus sequence are important for FOXO3a-DBD recognition of the consensus binding site.
Two kinds of crystalline/amorphous nanolaminates (C/ANLs),
i.e.
, Ag/Cu-Zr and Mo/Cu-Zr, with a wide range of modulation ratios
η
(thickness ratio of the amorphous layer to the crystalline layer) ...from 0.1 up to 9.0 were, respectively, prepared using magnetron sputtering. The hardness and the strain rate sensitivity
m
were measured for comparison through nanoindentation testing. The mechanical properties displayed a strong
η
-dependence, which was tuned by the crystalline phases. With the increase of
η
, the hardness increased in the Ag/Cu-Zr nanolaminates while it decreased in the Mo/Cu-Zr ones. However, the two C/ANLs showed similar variations in
m
that was reduced gradually from positive values at small
η
to negative values at large
η
. Microstructural examination demonstrated that the amorphous Cu-Zr layers in both the C/ANLs showed a deformation-induced crystallization (DIC) phenomenon within the nanoindentation deformation zone. The DIC was highly dependent on
η
and became more intense in the Mo/Cu-Zr than in the Ag/Cu-Zr C/ANLs. The
η
- and constituent-dependent DIC behaviors were rationalized in light of the stress field applied on the amorphous layers that is sensitive to both the amorphous layer thickness and the crystalline constituents. This DIC-induced negative
m
in amorphous layers competed with the positive
m
in crystalline layers, leading to a negative-to-positive change in
m
on reducing
η
. The underlying deformation mechanism was revealed to be the cooperation between dislocation activities in the crystalline layers and shear transformation zone motions in the amorphous layers. Furthermore, a modified mechanistic model was utilized to quantitatively describe the
η
-dependent hardness at different crystalline constituents.
The tunable mechanical properties and deformation behavior in crystalline/amorphous nanolaminates are revealed to be through cooperation between dislocations and shear transformation zones.
Interfaces often dominate plastic response of nanostructured metallic materials, e.g., nanolaminates (NLs), and thus engineering NLs to introduce controllable interfacial properties is a grand ...challenge. In this work, we comparatively studied the mechanical properties of both crystalline/crystalline NLs (C/CNLs) and crystalline/amorphous NLs (C/ANLs) in terms of the Hall-Petch slope (k) and the peak hardness (Hpeak). To characterize the interfacial properties of Cu-based NLs, we propose an energy factor (χ) in light of the interfacial residual dislocation energy determined by the coupling effects of lattice and moduli mismatch and the increased system energy caused by transmission slip determined by the mixing enthalpy (ΔHmix). It is found that this energy factor χ can quantitatively capture well the variation of Hall-Petch slope k and peak hardness Hpeak of NLs with different types of interfaces. There are linear relationships for both k – χ and Hpeak – χ plots. For the C/CNLs with positive ΔHmix, both k and Hpeak decrease with increasing χ, whereas for both the C/CNLs with negative ΔHmix and the C/ANLs, k decreases with decreasing χ while Hpeak decrease with increasing χ. The underlying mechanisms for the different mechanical properties of these NLs are elucidated from the perspective of diatomic interactions characterized by the ΔHmix of a given NL system. These experimental findings provide deep insights into designing tunable interfacial structures in metallic materials to realize their high performance.
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•An energy factor is used to characterize the interfacial properties of nanolaminates.•The energy factor capture the variation of Hall-Petch slope and peak hardness.•The energy factor linearly scales with both Hall-Petch slope and peak hardness.•The scaling laws are affected by the mixing heat and microstructure of nanolaminates.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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