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1.
Phys Rev Lett ; 89(22): 222001, 2002 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-12485061

RESUMO

Using 13.53 fb(-1) of CLEO data, we have measured the ratios of the branching fractions R(+)(e),R(+)(mu) and the combined branching fraction ratio R(+)(l), defined by R(+)(l)=[B(D+-->K(*0)l(+)nu(l))]/[B(D+-->K-pi(+)pi(+))]. We find R(+)(e)=0.74+/-0.04+/-0.05, R(+)(mu)=0.72+/-0.10+/-0.05, and R(+)(l)=0.74+/-0.04+/-0.05, where the first and second errors are statistical and systematic, respectively. The known branching fraction B(D+-->K-pi(+)pi(+)) leads to B(D+-->K(*0)e(+)nu(e))=(6.7+/-0.4+/-0.5+/-0.4)%, B(D+-->K(*0)mu(+)nu(mu))=(6.5+/-0.9+/-0.5+/-0.4)%, and B(D+-->K(*0)l(+)nu(l))=(6.7+/-0.4+/-0.5+/-0.4)%, where the third error is due to the uncertainty in B(D+-->K-pi(+)pi(+)).

2.
Phys Rev Lett ; 87(6): 061801, 2001 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-11497821

RESUMO

Using 12.7 fb(-1) of data collected with the CLEO detector at CESR, we observed two-photon production of the cc states chi(c0) and chi(c2) in their decay to pi(+)pi(-)pi(+)pi(-). We measured gamma(gammagamma)(chi(c))xB(chi(c)-->pi(+)pi(-)pi(+)pi(-)) to be 75+/-13(stat)+/-8(syst) eV for the chi(c0) and 6.4+/-1.8(stat)+/-0.8(syst) eV for the chi(c2), implying gamma(gammagamma)(chi(c0)) = 3.76+/-0.65(stat)+/-0.41(syst)+/-1.69(br) keV and gamma(gammagamma)(chi(c2)) = 0.53+/-0.15(stat)+/-0.06(syst)+/-0.22(br) keV. Also, cancellation of dominant experimental and theoretical uncertainties permits a precise comparison of gamma(gammagamma)(chi(c0))/gamma(gammagamma)(chi(c2)), evaluated to be 7.4+/-2.4(stat)+/-0.5(syst)+/-0.9(br), with QCD-based predictions.

3.
Phys Rev Lett ; 87(7): 071802, 2001 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-11497880

RESUMO

We present an observation and time-integrated rate measurement of the decay D(0)-->K(+)pi(-)pi(0) produced in 9 fb(-1) of e(+)e(-) collisions near the Upsilon(4S) resonance. The signal is inconsistent with an upward fluctuation of the background by 4.9 standard deviations. We measured the time-integrated rate of D(0)-->K(+)pi(-)pi(0) normalized to the rate of D(0)-->K(+)pi(-)pi(0) to be 0.0043(+0.0011)(-0.0010) (stat)+/-0.0007 (syst). This decay can be produced by doubly Cabibbo-suppressed decays or by the D(0) evolving into a D(0) through mixing, followed by a Cabibbo-favored decay to K(+)pi(-)pi(0). We also found the CP asymmetry A = (9(+25)(-22))% be consistent with zero.

4.
Phys Rev Lett ; 86(14): 2950-4, 2001 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-11290080

RESUMO

We report results of a search for B-->tau(nu) in a sample of 9.7 x 10(6) charged B meson decays. We exclusively reconstruct the companion B decay to suppress background. We set an upper limit on the branching fraction B(B-->tau(nu))<8.4 x 10(-4) at 90% confidence level. We also establish B(B+/--->K+/-nu(nu))<2.4 x 10(-4) at 90% confidence level.

5.
Phys Rev Lett ; 85(15): 3095-9, 2000 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-11019275

RESUMO

Using 13.4 fb(-1) of data collected with the CLEO detector at the Cornell Electron Storage Ring, we have observed 300 events for the two-photon production of ground-state pseudoscalar charmonium in the decay eta(c)-->K(0)(S)K-/+pi(+/-). We have measured the eta(c) mass to be [2980.4+/-2.3 (stat)+/-0.6 (syst)] MeV and its full width as [27.0+/-5.8 (stat)+/-1.4 (syst)] MeV. We have determined the two-photon partial width of the eta(c) meson to be [7.6+/-0.8 (stat)+/-0.4 (syst)+/-2.3 (br)] keV, with the last uncertainty associated with the decay branching fraction.

6.
Arch Otolaryngol Head Neck Surg ; 121(7): 795-9, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7598860

RESUMO

Transverse fractures often violate the otic capsule and commonly, although not invariably, result in immediate and profound sensorineural hearing loss. The pathogenic mechanisms producing sensorineural hearing loss include direct trauma to the cochlear nerve, disruption of the membranous labyrinth, vascular compromise or hemorrhage into the inner ear, perilymphatic fistula, and endolymphatic hydrops. The last two mechanisms account for the occasional patient who develops progressive sensorineural hearing loss after the initial insult. On early posttraumatic evaluation three patients were discovered to have transverse fractures and residual auditory function. Deterioration of hearing led to middle-ear exploration with closure of perilymphatic fistulas. Hearing was preserved in two patients. Diagnosis of posttraumatic perilymphatic fistulas requires early audiometric assessment, high-resolution computed tomographic scanning of the temporal bones to detect fracture of the otic capsule and pneumolabyrinth, and a high index of clinical suspicion.


Assuntos
Perda Auditiva Neurossensorial/etiologia , Fraturas Cranianas/complicações , Osso Temporal/lesões , Acidentes por Quedas , Adulto , Evolução Fatal , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/cirurgia , Humanos , Masculino , Fraturas Cranianas/diagnóstico , Fraturas Cranianas/cirurgia , Osso Temporal/cirurgia , Fatores de Tempo , Violência
7.
Am J Otol ; 14(4): 386-91, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8238277

RESUMO

Postoperative plain film x-rays are necessary in all multichannel cochlear implant patients to confirm intracochlear position, detect possible electrode kinking, and provide a reference if postoperative slippage occurs. In addition, precise documentation of multichannel intracochlear electrode insertion depths is necessary for comparison of speech recognition results among patients and may be of use for future speech processing strategies. In the present study, a method has been devised, using a modified Stenver's view, to more accurately document insertion depths of the electrode array and location of individual electrodes on 50 multichannel cochlear implant patients. Surgical estimates of insertion depth are shown to have great variability in regard to distance along the basilar membrane when compared with x-ray documentation. Additionally, there is preliminary evidence that insertion depth, as determined by x-ray studies, has a strong correlation with open-set speech discrimination.


Assuntos
Cóclea/fisiopatologia , Doenças Cocleares/reabilitação , Implantes Cocleares , Membrana Basilar/cirurgia , Cóclea/diagnóstico por imagem , Cóclea/cirurgia , Doenças Cocleares/cirurgia , Orelha Interna/cirurgia , Orelha Média/diagnóstico por imagem , Eletrodos Implantados , Feminino , Humanos , Masculino , Projetos Piloto , Canais Semicirculares/diagnóstico por imagem , Canais Semicirculares/cirurgia , Tomografia Computadorizada por Raios X
8.
Arch Otolaryngol Head Neck Surg ; 118(11): 1257-65, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1418907

RESUMO

The temporal bone histopathologic findings of a patient having received a Nucleus 22-channel cochlear implant (Cochlear Corp, Englewood, Colo) following bilateral transverse otic capsule fractures is presented. The case was complicated by perilymph fistulas, labyrinthitis, meningitis, and death due to drowning. The left cochlea revealed complete labyrinthitis ossificans; the implanted right cochlea demonstrated new bone formation in the basal turn of the scala tympani, degeneration of the organ of Corti, but normal ganglion cell counts. Results of psychophysical and speech perception 4 months after implantation are presented.


Assuntos
Implantes Cocleares , Osso Temporal/lesões , Osso Temporal/patologia , Adulto , Audiometria , Traumatismos Cranianos Fechados/complicações , Traumatismos Cranianos Fechados/cirurgia , Humanos , Masculino , Psicofísica , Percepção da Fala
10.
Am J Otol ; 13(3): 241-8, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1609853

RESUMO

The temporal bone histopathology of a patient with profound sensorineural hearing loss attributable to cochlear otosclerosis is presented. The patient had a Nucleus 22-channel cochlear prosthesis implanted in the right ear prior to his demise. Unintentional scala media insertion of the electrode array resulted from labyrinthitis ossificans obliteration of the scala tympani. Inadvertent facial nerve stimulation necessitated program exclusion of electrodes 11 to 16 located in proximity to the labyrinthine and geniculate segments of the facial nerve. The patient received significant benefit from use of the device. The histopathologic findings are correlated with psychophysical and speech perception results.


Assuntos
Implantes Cocleares , Otosclerose/patologia , Osso Temporal/patologia , Doenças Cocleares/patologia , Doenças Cocleares/fisiopatologia , Nervo Facial/fisiopatologia , Perda Auditiva Neurossensorial/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Psicofísica , Percepção da Fala , Osso Temporal/ultraestrutura
12.
Otolaryngol Head Neck Surg ; 104(6): 803-8, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1908971

RESUMO

Ossifying fibroma is benign, usually slow-growing tumor that may behave in an unpredictably aggressive fashion. Most of these unusual tumors affect the mandible. Their behavior in the mid-face and paranasal sinuses is not well documented. In our review of the subject, and of the cases presented, it appears that these lesions behave more aggressively than their mandibular counterparts. A more aggressive approach may be more beneficial than expectant observation or curettage in the initial management of this neoplasm.


Assuntos
Seio Etmoidal , Fibroma/diagnóstico , Osteoma/diagnóstico , Neoplasias dos Seios Paranasais/diagnóstico , Neoplasias Cranianas/diagnóstico , Seio Esfenoidal , Zigoma , Adolescente , Adulto , Criança , Feminino , Fibroma/cirurgia , Humanos , Masculino , Osteoma/cirurgia , Neoplasias dos Seios Paranasais/cirurgia , Neoplasias Cranianas/cirurgia
13.
Otolaryngol Clin North Am ; 24(3): 675-89, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1762783

RESUMO

There is no consensus on the cause of Bell's palsy, just as there is no proven medical therapy. Disregarding the numerous theoretic causes, preponderant anatomic, electrophysiologic, radiologic, clinical, and pathologic evidence supports entrapment at the medical foramen of the fallopian canal as a final common pathway resulting in facial nerve ischemia and degeneration. Middle cranial fossa decompression of the meatal foramen may benefit those patients most severely affected with Bell's palsy.


Assuntos
Paralisia Facial/cirurgia , Eletrodiagnóstico , Paralisia Facial/diagnóstico , Paralisia Facial/etiologia , Paralisia Facial/terapia , Humanos , Imageamento por Ressonância Magnética , Resultado do Tratamento
14.
Otolaryngol Clin North Am ; 24(2): 447-71, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1857622

RESUMO

The basic electonystagmography battery (saccade, gaze, position, caloric tests, and spontaneous nystagmus) are described along with rotational testing and dynamic posturography. Emphasis is placed on interpretation, relative benefits, and limitations as an aid in diagnosis.


Assuntos
Perda Auditiva Neurossensorial/diagnóstico , Testes de Função Vestibular , Testes Calóricos , Eletronistagmografia , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Anamnese , Rotação
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