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1.
Science ; 162(3859): 1302-3, 1968 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-5699209

RESUMO

The consensual response of the pupil in the cat was driven by means of a light flux impinging on the contralateral retina. Spike trains recorded extracellularly from single units in the midbrain show correlation with the concurrently recorded pupil area. The temporal dynamics found confirm two earlier studies of sinigle-unit responses and quantitative nerve stimulation. Both of these indicate that most of the 200-millisecond transport delay resides in the neuromuscular apparatus. Neurons whose activity correlated either with constriction with dilatation phases of Change in the pupil area were observed.


Assuntos
Luz , Mesencéfalo/fisiologia , Neurônios/fisiologia , Pupila/fisiologia , Animais , Gatos , Computadores , Constrição , Dilatação , Junção Neuromuscular/fisiologia , Pupila/efeitos da radiação , Efeitos da Radiação
18.
Phys Rev Lett ; 87(25): 251808, 2001 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-11736567

RESUMO

We have measured the first and second moments of the hadronic mass-squared distribution in B-->X(c)l nu, for P(lepton)>1.5 GeV/c. We find = 0.251+/-0.066 GeV(2), <(M(2)(X)-)(2)> = 0.576+/-0.170 GeV(4), where M macro(D) is the spin-averaged D meson mass. From that first moment and the first moment of the photon energy spectrum in b-->s gamma, we find the heavy quark effective theory parameter lambda(1) (in the modified minimal subtraction renormalization scheme, to order 1/M(3)(B) and beta(0)alpha(2)(s)) to be -0.24+/-0.11 GeV(2). Using these first moments and the B semileptonic width, and assuming parton-hadron duality, we obtain absolute value of V(cb) = 0.0404+/-0.0013.

19.
Phys Rev Lett ; 86(11): 2232-6, 2001 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-11289897

RESUMO

The Lambda+c lifetime is measured using 9.0 fb(-1) of e+e- annihilation data collected on or just below the Upsilon(4S) resonance with the CLEO II.V detector at CESR. Using an unbinned maximum likelihood fit, the Lambda+c lifetime is measured to be 179.6+/-6.9(stat)+/-4.4(syst) fs. The precision of this colliding beam measurement is comparable to other measurements, which are based on fixed-target experiments, with different systematic uncertainties.

20.
Phys Rev Lett ; 86(20): 4479-82, 2001 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-11384263

RESUMO

Using 13.7 fb(-1) of data recorded by the CLEO detector at the Cornell Electron Storage Ring, we investigate the spectrum of charmed baryons which decay into Lambda+(c)pi(-)pi(+) and are more massive than the Lambda+(c)(2625) baryon. We find evidence for two new states: one is broad and has an invariant mass roughly 480 MeV above that of the Lambda+(c) baryon; the other is narrow with an invariant mass of 596+/-1+/-2 MeV above the Lambda+(c) mass.

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