61,183 research outputs found
U.S. President Lyndon B. Johnson delivers a public address on Thanksgiving Day 1963
No full textPresident Lyndon B. Johnson delivers a public address on Thanksgiving Day 1963. In honor of the memory of President Kennedy, he plans to change the name of the NASA Launch Operation Center in Florida to the John F. Kennedy Space Center and Cape Canaveral to Cape Kennedy
Letter from G. F. Rankin, Acting Dean of School of Agriculture at North Carolina Agricultural & Technical State University, to W. T. Johnson
No full textLetter from G. F. Rankin, Acting Dean of School of Agriculture at North Carolina Agricultural & Technical State University, to W. T. Johnson, congratulating him on opening of S. B. Simmons camp. Note for souvenir program
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
No full textFirst evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
No full textThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
Measurement of the branching fraction
No full textThe B
0
s
→ J/ψK
0
S
branching fraction is measured in a data sample corresponding to 0.41 fb−1
of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to
the penguin contributions affecting the sin 2β measurement from B
0
→ J/ψK
0
S
. The time-integrated
branching fraction is measured to be B(B
0
s
→ J/ψK
0
S
) = (1.83±0.28)×10−5
. This is the most precise
measurement to date
Measurement of b-hadron masses
No full textMeasurements of b-hadron masses are performed with the exclusive decay modes B +→J/ψK +, B 0→J/ψK +, B0→J/ψKS0, Bs0→J/ψφ and Λb0→J/ψΛ using an integrated luminosity of 35pb -1 collected in pp collisions at a centre-of-mass energy of 7 TeV by the LHCb experiment. The momentum scale is calibrated with J/ψ→μ +μ - decays and verified to be known to a relative precision of 2 ×10 -4 using other two-body decays. The results are more precise than previous measurements, particularly in the case of the Bs0 and Λb0 masses
Observations of Bºs→ψ(2S)η and Bº(s)→ψ(2S)π+π- decays
No full textFirst observations of the B0s
→ψ(2S)η, B0 →ψ(2S)π
+
π
− and B0s
→ψ(2S)π
+
π
− decays are made
using a dataset corresponding to an integrated luminosity of 1.0 fb−1 collected by the LHCb experiment in
proton–proton collisions at a centre-of-mass energy of
√
s = 7 TeV. The ratios of the branching fractions
of each of the ψ(2S) modes with respect to the corresponding J/ψ decays are
B(B0s
→ψ(2S)η)
÷
B(B0s
→J/ψη)
= 0.83± 0.14 (stat)±0.12 (syst) ±0.02 (B),
;
B(B0→ψ(2S)π
+
π
−
)
÷
B(B0→J/ψπ
+
π
−
)
= 0.56± 0.07 (stat)±0.05 (syst)± 0.01 (B),
;
B(B0s
→ψ(2S)π
+
π
−
)
÷
B(B0s
→J/ψπ
+
π
−
)
= 0.34± 0.04 (stat)±0.03 (syst)± 0.01 (B),
where the third uncertainty corresponds to the uncertainties of the dilepton branching fractions of the J/ψ
and ψ(2S) meson decays
Newly sworn in U.S. President Lyndon Johnson gives a message to the people regarding the state of the White House following the assassination of President John Fitzgerald Kennedy
No full textNewly sworn President Lyndon Baines Johnson delivers a message to the American people eulogizing John F. Kennedy. A reporter comments on the state of the White House and Washington as Johnson assumes the Presidency
Total Syntheses of Cyanthiwigins B, F, and G
No full textA concise and versatile approach toward the preparation of the cyanthiwigin family of cyathane natural products is described. By leveraging a unique double asymmetric catalytic alkylation procedure it is possible to quickly establish two of the most critical stereocenters of the cyanthiwigin framework with high levels of selectivity and expediency. The synthetic route additionally employs both a tandem ring-closing cross-metathesis reaction, and an aldehyde-olefin radical cyclization process, in order to rapidly arrive at the tricyclic cyathane core of the cyanthiwigin molecules. From this unifying intermediate, the preparations of cyanthiwigins B, F, and G are attained swiftly and without the need for protecting groups.This publication is based on work supported by Award No. KUS-11-006-02, made by King Abdullah University of Science and Technology (KAUST). The authors wish to thank NIH-NIGMS (R01M080269-01), Amgen, Abbott, Boehringer Ingelheim, Merck, and Bristol-Myers Squibbs, GlaxoSmithKline, Johnson and Johnson, Amgen, Merck Research Laboratories, Pfizer, Novartis, Roche, Abbott Laboratories, Boehringer-Ingelheim, AstraZeneca, and Caltech for financial support. We also wish to thank Dr. M. W. Day and Mr. L. M. Henling for X-ray crystallographic expertise, Dr. Andrew Harned, Dr. David White, Daniel Caspi, and J. T. Mohr for helpful discussions, and Professor Mark T. Hamann for authentic samples and spectra of cyanthiwigins B, F, and G. Ruthenium olefin metathesis catalysts were generously donated by Materia
FIGURE 1. Navarretia minima. A, B, F in Restoring the original taxonomic concept for Navarretia minima (Polemoniaceae): a revised synonymy and new combination
No full textFIGURE 1. Navarretia minima. A, B, F: isolectotype at GH (Nuttall s.n.). C: topotype of N. furnissii (Johnson 08-033, BRY) collected 3 July 2008. D, E: isolectotype at PH (Nuttall, s.n.). G. lectotype and associated specimen at BM (both Nuttall s.n.). A, C, D at same magnification. Calyx and bract pubescence illustrated in B, E; yellow pollen in anthers apparent in F.Published as part of Johnson, Leigh A. & Gowen, David, 2022, Restoring the original taxonomic concept for Navarretia minima (Polemoniaceae): a revised synonymy and new combination, pp. 101-112 in Phytotaxa 576 (1) on page 103, DOI: 10.11646/phytotaxa.576.1.6, http://zenodo.org/record/744125
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