Using 2.93 fb(-1) of e(+)e(-) collision data collected with the BESIII detector at a center-of-mass energy of 3.773 GeV, we measure the absolute branching fractions of the decays D-0 -> ...K(-)e(+)nu(e) and D+ -> (K) over bar (0)e(+)nu(e) to be (3.567 +/- 0.031(stat) +/- 0.025(syst))% and (8.68 +/- 0.14(stat) +/- 0.16(syst))%, respectively. Starting with the process e(+)e(- ) -> D (D) over bar, a new reconstruction method is employed to select events that contain candidates for both D -> (K) over bare(+)nu(e) and (D) over bar -> Ke(-)(nu) over bar (e) decays. The branching fractions reported in this work are consistent within uncertainties with previous BESIII measurements that selected events containing D -> (K) over bare(+)nu(e) and hadronic (D) over bar decays. Combining our results with the lifetimes of the D degrees and D+ mesons and the previous BESIII measurements leads to a ratio of the two decay partial widths of (Gamma) over bar (D0 -> K-e+)(nu e)/(Gamma) over bar (D+ -> (K) over bar 0e+)(nu e) = 1.039 +/- 0.021. This ratio supports isospin symmetry in the D-0 -> K(-)e(+)nu(e) and D+ -> (K) over bar (0)e(+)nu(e) decays within 1.9 sigma.
A
bstract
Using (10087 ± 44) × 10
6
J
/
ψ
events collected with the BESIII detector at the BEPCII
e
+
e
−
storage ring at the center-of-mass energy of
s
= 3.097 GeV, we present a search for the rare ...semi-muonic charmonium decay
J
/
ψ
→
D
−
μ
+
ν
μ
+ c.c.. Since no significant signal is observed, we set an upper limit of the branching fraction to be
B
(
J
/
ψ
→
D
−
μ
+
ν
μ
+ c.c.) < 5.6 × 10
−
7
at 90% confidence level. This is the first search for the weak decay of charmonium with a muon in the final state.
Chitosan-modified poly(lactic-co-glycolic acid) nanoparticles (CHI/PLGA NPs) loaded with 7-ethyl-10-hydroxycamptothecin (SN-38), named CHI/PLGA/SN-38 NPs, were successfully prepared using an ...oil-in-water (O/W) solvent evaporation method. The physicochemical properties of the novel NPs were characterized by DLS, Zeta potential, SEM, DSC, XRD, and FTIR. The encapsulation efficiency and drug loading content were 71.83 (±2.77)% and 6.79 (±0.26)%, respectively. In vitro drug release in the simulated gastric juice was lower than that in the intestinal juice. In situ single-pass intestinal perfusion (SPIP) studies indicated a dramatic improvement of drug absorption as a result of the synergistic effect between CHI and PLGA on P-glycoprotein (Pgp) inhibition. CHI/PLGA NPs showed high cellular uptake and low efflux for drugs in Caco-2 cells. The cytotoxicity studies revealed that CHI/PLGA NPs had a transient effect on the membrane integrity, but did not have an influence on cell viability. Based on the in vitro release studies, SPIP, and intracellular drug accumulation and transport investigations, we speculate rationally that CHI/PLGA NPs were mainly internalized in the form of intact NPs, thus escaping the recognition of enterocyte Pgp and avoiding efflux into the apical part of the enterocytes. After partial release of drugs inside the enterocytes, CHI/PLGA interfered with the microenvironment of Pgp and further weakened the Pgp-mediated efflux. Then, the drug-loaded NPs exited via the exocytose effect from the basal part of the enterocytes and entered the blood circulation. These results showed that CHI/PLGA NPs would be smart oral delivery carriers for antineoplastic agents that are also Pgp substrates.
In this letter, Global Positioning System (GPS) reflections for sea surface wind speed measurement are explored. The reflected signal correlation power is employed to retrieve the sea surface wind ...speed with a certain degree of accuracy. The GPS coarse-acquisition code autocorrelation sidelobe is studied and considered in the reflected signal model. This technique proves to be valid for the correlation power calculation. It is expected that this technique could further be studied for spaceborne applications with high dynamics.
Using data corresponding to an integrated luminosity of 651 pb-1 accumulated at 22 center-of-mass energies from 2.00 to 3.08 GeV by the BESIII experiment, the process e+e- → φπ+π- is studied. The ...cross sections for e+e- → φπ+π- are consistent with previous results, but with improved precision. To measure the mass and width of the structure observed in the cross section line shape, a combine fit is performed after enhancing the contribution from φ$f$0(980). The fit reveals a structure with the mass of M = 2178 ± 20 ± 5 MeV=c2 and the width of Γ = 140 ± 36 ± 16 MeV, where the first uncertainties are statistical and the second ones are systematic.
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