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1.
Oral Dis ; 25(2): 403-415, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29383862

RESUMO

Mice are a widely utilized in vivo model for translational salivary gland research but must be used with caution. Specifically, mouse salivary glands are similar in many ways to human salivary glands (i.e., in terms of their anatomy, histology, and physiology) and are both readily available and relatively easy and affordable to maintain. However, there are some significant differences between the two organisms, and by extension, the salivary glands derived from them must be taken into account for translational studies. The current review details pertinent similarities and differences between human and mouse salivary glands and offers practical guidelines for using both for research purposes.


Assuntos
Glândulas Salivares/anatomia & histologia , Glândulas Salivares/fisiologia , Pesquisa Translacional Biomédica , Animais , Bioengenharia , Técnicas Citológicas , Humanos , Camundongos , Células-Tronco Pluripotentes , Glândulas Salivares/metabolismo , Glândulas Salivares/transplante
2.
Phys Rev Lett ; 117(3): 030801, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27472106

RESUMO

A continuous quantum field, such as a propagating beam of light, may be characterized by a squeezing spectrum that is inhomogeneous in frequency. We point out that homodyne detectors, which are commonly employed to detect quantum squeezing, are blind to squeezing spectra in which the correlation between amplitude and phase fluctuations is complex. We find theoretically that such complex squeezing is a component of ponderomotive squeezing of light through cavity optomechanics. We propose a detection scheme called synodyne detection, which reveals complex squeezing and allows the accounting of measurement backaction. Even with the optomechanical system subject to continuous measurement, such detection allows the measurement of one component of an external force with sensitivity only limited by the mechanical oscillator's thermal occupation.

3.
Phys Rev Lett ; 110(26): 262502, 2013 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-23848867

RESUMO

The rate of the 18F(p,γ)19Ne reaction affects the final abundance of the γ-ray observable radioisotope 18F, produced in novae. However, no successful measurement of this reaction exists and the rate used is calculated from incomplete information on the contributing resonances. Of the two resonances thought to play a significant role, one has a radiative width estimated from the assumed analogue state in the mirror nucleus, 19F. The second does not have an analogue state assignment at all, resulting in an arbitrary radiative width being assumed. Here, we report the first successful direct measurement of the 18F(p,γ)^19Ne reaction. The strength of the 665 keV resonance (Ex=7.076 MeV) is found to be over an order of magnitude weaker than currently assumed in nova models. Reaction rate calculations show that this resonance therefore plays no significant role in the destruction of ^{18}F at any astrophysical energy.

4.
Phys Rev Lett ; 110(14): 142701, 2013 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-25166983

RESUMO

The inclusive breakup for the (11)Li + (208)Pb reaction at energies around the Coulomb barrier has been measured for the first time. A sizable yield of (9)Li following the (11)Li dissociation has been observed, even at energies well below the Coulomb barrier. Using the first-order semiclassical perturbation theory of Coulomb excitation it is shown that the breakup probability data measured at small angles can be used to extract effective breakup energy as well as the slope of B(E1) distribution close to the threshold. Four-body continuum-discretized coupled-channels calculations, including both nuclear and Coulomb couplings between the target and projectile to all orders, reproduce the measured inclusive breakup cross sections and support the presence of a dipole resonance in the (11)Li continuum at low excitation energy.

5.
Phys Rev Lett ; 108(21): 210403, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-23003223

RESUMO

The macroscopic tunneling of an optomechanical membrane is considered. A cavity mode which couples quadratically to the membranes position can create highly tunable adiabatic double-well potentials, which together with the high Q factors of such membranes render the observation of macroscopic tunneling possible. A suitable, pulsed measurement scheme using a linearly coupled mode of the cavity for the verification of the effect is studied.

6.
Phys Rev Lett ; 109(26): 262701, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23368554

RESUMO

The first measurement of the elastic scattering of the halo nucleus 11Li and its core 9Li on 208Pb at energies near the Coulomb barrier is presented. The 11Li+208Pb elastic scattering shows a strong reduction with respect to the Rutherford cross section, even at energies well below the barrier and down to very small scattering angles. This drastic change of the elastic differential cross section observed in 11Li+208Pb is the consequence of the halo structure of 11Li, as it is not observed in the elastic scattering of its core 9Li at the same energies. Four-body continuum-discretized coupled-channels calculations, based on a three-body model of the 11Li projectile, are found to explain the measured angular distributions and confirm that the observed reduction is mainly due to the strong Coulomb coupling to the dipole states in the low-lying continuum of 11Li. These calculations suggest the presence of a low-lying dipole resonance in 11Li close to the breakup threshold.

7.
Phys Rev Lett ; 106(22): 223601, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21702598

RESUMO

We investigate the cavity optomechanical properties of an antiferromagnetic Bose-Einstein condensate, where the role of the mechanical element is played by spin-wave excitations. We show how this system can be described by a single rotor that can be prepared deep in the quantum regime under realizable experimental conditions. This system provides a bottom-up realization of dispersive rotational optomechanics, and opens the door to the direct observation of quantum spin fluctuations.

8.
Phys Rev Lett ; 105(15): 152501, 2010 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-21230896

RESUMO

The radionuclide 22Na is a potential astronomical observable that is expected to be produced in classical novae in quantities that depend on the thermonuclear rate of the 22Na(p,γ)23Mg reaction. We have measured the strengths of low-energy 22Na(p,γ)23Mg resonances directly and absolutely using a radioactive 22Na target. We find the strengths of resonances at Ep=213, 288, 454, and 610 keV to be higher than previous measurements by factors of 2.4-3.2, and we exclude important contributions to the rate from proposed resonances at Ep=198, 209, and 232 keV. The 22Na abundances expected in the ejecta of classical novae are reduced by a factor of ≈2.

9.
Phys Rev Lett ; 101(21): 212501, 2008 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-19113404

RESUMO

The deuteron-emission channel in the beta decay of the halo nucleus (11)Li was measured at the Isotope Separator and Accelerator facility at TRIUMF by implanting postaccelerated (11)Li ions into a segmented silicon detector. The events of interest were identified by correlating the decays of (11)Li with those of the daughter nuclei. This method allowed the energy spectrum of the emitted deuterons to be extracted, free from contributions from other channels, and a precise value for the branching ratio B(d)=1.30(13)x10(-4) to be deduced for E(c.m.)>200 keV. The results provide the first unambiguous experimental evidence that the decay takes place essentially in the halo of (11)Li and that it proceeds mainly to the (9)Li+d continuum, opening up a new means to study the halo wave function of (11)Li.

10.
Phys Rev Lett ; 100(19): 192502, 2008 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-18518445

RESUMO

The p((11)Li, (9)Li)t reaction has been studied for the first time at an incident energy of 3A MeV at the new ISAC-2 facility at TRIUMF. An active target detector MAYA, built at GANIL, was used for the measurement. The differential cross sections have been determined for transitions to the (9)Li ground and first excited states in a wide range of scattering angles. Multistep transfer calculations using different (11)Li model wave functions show that wave functions with strong correlations between the halo neutrons are the most successful in reproducing the observation.

11.
Phys Rev Lett ; 96(25): 252501, 2006 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-16907298

RESUMO

The strength of the Ec.m. = 184 keV resonance in the 26gAl(p, gamma)27 reaction has been measured in inverse kinematics using the DRAGON recoil separator at TRIUMF's ISAC facility. We measure a value of omega gamma = 35 +/- 7 microeV and a resonance energy of Ec.m. = 184 +/- 1 keV, consistent with p-wave proton capture into the 7652(3) keV state in 27Si, and discuss the implications of these values for 26GAl nucleosynthesis in typical oxygen-neon white-dwarf novae.

12.
Phys Rev Lett ; 97(24): 242503, 2006 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17280274

RESUMO

Radiative alpha-particle capture into the first excited, J(pi)=0+ state of 16O at 6.049 MeV excitation energy has rarely been discussed as contributing to the 12C(alpha,gamma)16O reaction cross section due to experimental difficulties in observing this transition. We report here measurements of this radiative capture in 12C(alpha,gamma)16O for center-of-mass energies of E=2.22 MeV to 5.42 MeV at the DRAGON recoil separator. To determine cross sections, the acceptance of the recoil separator has been simulated in GEANT as well as measured directly. The transition strength between resonances has been identified in R-matrix fits as resulting both from E2 contributions as well as E1 radiative capture. Details of the extrapolation of the total cross section to low energies are then discussed [S6.0(300)=25(-15)(+16) keV b] showing that this transition is likely the most important cascade contribution for 12C(alpha,gamma)16O.

13.
Phys Rev Lett ; 90(16): 162501, 2003 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-12731972

RESUMO

The 21Na(p,gamma)22Mg reaction is expected to play an important role in the nucleosynthesis of 22Na in oxygen-neon novae. The decay of 22Na leads to the emission of a characteristic 1.275 MeV gamma-ray line. This report provides the first direct measurement of the rate of this reaction using a radioactive 21Na beam, and discusses its astrophysical implications. The energy of the important state was measured to be E(c.m.)=205.7+/-0.5 keV with a resonance strength omegagamma=1.03+/-0.16(stat)+/-0.14(sys) meV.

14.
Phys Rev Lett ; 88(7): 072501, 2002 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-11863889

RESUMO

Angular distributions of 12C(alpha,alpha)12C have been measured for E(alpha) = 2.6-8.2 MeV, at angles from 24 to 166, yielding 12 864 data points. R-matrix analysis of the ratios of elastic scattering yields a reduced width amplitude of gamma12 = 0.47 +/- 0.06 MeV(1/2) for the Ex = 6.917 MeV (2+) state in 16O(a = 5.5 fm). The dependence of the chi2 surface on the interaction radius a has been investigated and a deep minimum is found at a = 5.42(+0.16)(-0.27) fm. Using this value of gamma12, radiative alpha capture and 16N beta-delayed alpha-decay data, the S factor is calculated at E(c.m.) = 300 keV to be S(E2)(300) = 53(+13)(-18) keV b for destructive interference between the subthreshold resonance tail and the ground state E2 direct capture.

15.
Phys Rev Lett ; 88(4): 041101, 2002 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-11801101

RESUMO

We measured the 7Be(p,gamma)8B cross section from E(c.m.) = 186 to 1200 keV, with a statistical-plus-systematic precision per point of better than +/-5%. All important systematic errors were measured including 8B backscattering losses. We obtain S17(0) = 22.3+/-0.7(expt)+/-0.5(theor) eV b from our data at E(c.m.)< or =300 keV and the theory of Descouvemont and Baye.

18.
Ann Otol Rhinol Laryngol ; 104(7): 516-21, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7598362

RESUMO

Selected characteristics were compared in the speech and voice of 28 treated with a supracricoid partial laryngectomy (SCPL) and of 14 normal adult laryngeal (NAL) speakers. Tape-recorded speech samples were measured for durational features with a stopwatch. Frequency features were analyzed with the Computerized Speech Lab and a multidimensional voice program. The SCPL speech proved comparable to NAL speech in average fundamental frequency. The SCPL speech and voice were statistically less efficient than NAL speech in fundamental frequency range, jitter, shimmer, noise to harmonics ratio, maximum phonation time, speech rate, and phrase grouping. The completion of an arytenoid cartilage resection did not statistically modify the duration and frequency features of SCPL speakers. Among SCPL speakers 1) the average fundamental frequency was statistically higher (p = .02) in patients who underwent a cricohyoidoepiglottopexy when compared to patients who underwent a cricohyoidopexy, 2) the maximum phonation time was statistically related to the patient's age (p = .002), and 3) the jitter and shimmer values were statistically related (p = .01 and p = .005) to the time elapsed since SCPL completion. Explanations and implications of these findings are discussed.


Assuntos
Laringectomia , Fala , Voz , Adulto , Carcinoma de Células Escamosas/cirurgia , Humanos , Neoplasias Laríngeas/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
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