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Primer on adult patient satisfaction in perioperative settings.
The topic of patient satisfaction has gained increasing importance over the past decade. Due to the impact of patient satisfaction on health care quality, understanding factors that predict satisfaction is vital. The purpose of this review is to examine the literature and identify factors related to patient perioperative satisfaction as well as predictive variables that, if modified, can enhance satisfaction scores of patients undergoing surgery. Our review reports that patient satisfaction scores are affected by modifiable factors such as clinician-patient communication, information provision to patients, and operational function of a hospital. Non-modifiable factors affecting patient satisfaction scores include patient demographics such as gender, age, and education. In order to enhance patient perioperative satisfaction, we suggest that anesthesiologists and surgeons focus their efforts on enhancing their communication skills and providing information that is appropriately tailored to the understanding of their patients
On the electromagnetic form factors of the proton from generalized Skyrme models
We compare the prediction of Skyrme-like effective Lagrangians with data for
electromagnetic form factors of proton and consider the possibility of fixing
the parameters of these higher-order Lagrangians. Our results indicate that one
or two-parameter models can lead to better agreement with the data but more
accurate determination of the effective Lagragian faces theoretical
uncertainties.Comment: 8 pages, 2 figures, revte
Optical Lattice Induced Light Shifts in an Yb Atomic Clock
We present an experimental study of the lattice induced light shifts on the
1S_0-3P_0 optical clock transition (v_clock~518 THz) in neutral ytterbium. The
``magic'' frequency, v_magic, for the 174Yb isotope was determined to be 394
799 475(35)MHz, which leads to a first order light shift uncertainty of 0.38 Hz
on the 518 THz clock transition. Also investigated were the hyperpolarizability
shifts due to the nearby 6s6p 3P_0 - 6s8p 3P_0, 6s8p 3P_2, and 6s5f 3F_2
two-photon resonances at 759.708 nm, 754.23 nm, and 764.95 nm respectively. By
tuning the lattice frequency over the two-photon resonances and measuring the
corresponding clock transition shifts, the hyperpolarizability shift was
estimated to be 170(33) mHz for a linear polarized, 50 uK deep, lattice at the
magic wavelength. In addition, we have confirmed that a circularly polarized
lattice eliminates the J=0 - J=0 two-photon resonance. These results indicate
that the differential polarizability and hyperpolarizability frequency shift
uncertainties in a Yb lattice clock could be held to well below 10^-17.Comment: Accepted to PR
Proton decay of high-lying states in odd nuclei
In the framework of the quasiparticle-phonon model, we study the
non-statistical proton decay of excited states in odd nuclei towards low-lying
collective states. Partial cross sections and branching ratios for the proton
decay of the high angular momentum states in Sc, Cu and Nb
%{\it excited by means of the (Li,He) reaction} are evaluated. The
calculated branching ratios predict strong direct proton decays to the
low-lying vibrational states in Sc and Nb. A general agreement
with existing experimental data is found.Comment: 12 pages, 2 figures, Latex, accepted for publication in Nucl. Phys.
Frequency evaluation of the doubly forbidden transition in bosonic Yb
We report an uncertainty evaluation of an optical lattice clock based on the
transition in the bosonic isotope Yb by use
of magnetically induced spectroscopy. The absolute frequency of the
transition has been determined through comparisons
with optical and microwave standards at NIST. The weighted mean of the
evaluations is (Yb)=518 294 025 309 217.8(0.9) Hz. The uncertainty
due to systematic effects has been reduced to less than 0.8 Hz, which
represents in fractional frequency.Comment: 4 pages, 3 figure -Submitted to PRA Rapid Communication
Sub-femtosecond absolute timing precision with a 10 GHz hybrid photonic-microwave oscillator
We present an optical-electronic approach to generating microwave signals
with high spectral purity. By circumventing shot noise and operating near
fundamental thermal limits, we demonstrate 10 GHz signals with an absolute
timing jitter for a single hybrid oscillator of 420 attoseconds (1Hz - 5 GHz)
Anisotropy of the Seebeck Coefficient in the Cuprate Superconductor YBaCuO: Fermi-Surface Reconstruction by Bidirectional Charge Order
The Seebeck coefficient of the cuprate YBaCuO was
measured in magnetic fields large enough to suppress superconductivity, at hole
dopings and , for heat currents along the and
directions of the orthorhombic crystal structure. For both directions,
decreases and becomes negative at low temperature, a signature that the Fermi
surface undergoes a reconstruction due to broken translational symmetry. Above
a clear threshold field, a strong new feature appears in , for
conduction along the axis only. We attribute this feature to the onset of
3D-coherent unidirectional charge-density-wave modulations seen by x-ray
diffraction, also along the axis only. Because these modulations have a
sharp onset temperature well below the temperature where starts to drop
towards negative values, we infer that they are not the cause of Fermi-surface
reconstruction. Instead, the reconstruction must be caused by the quasi-2D
bidirectional modulations that develop at significantly higher temperature.Comment: 7 pages, 5 figure
Unbound exotic nuclei studied by projectile fragmentation
We call "projectile fragmentation" of neutron halo nuclei the elastic breakup
(diffraction) reaction, when the observable studied is the neutron-core
relative energy spectrum. This observable has been measured in relation to the
Coulomb breakup on heavy target and recently also on light targets. Such data
enlighten the effect of the neutron final state interaction with the core of
origin. Projectile fragmentation is studied here by a time dependent model for
the excitation of a nucleon from a bound state to a continuum resonant state in
a neutron-core complex potential which acts as a final state interaction.
The final state is described by an optical model S-matrix so that both
resonant and non resonant states of any continuum energy can be studied as well
as deeply bound initial states. It turns out that due to the coupling between
the initial and final states, the neutron-core free particle phase shifts are
modified, in the exit channel, by an additional phase.
Some typical numerical calculations for the relevant observables are
presented and compared to experimental data. It is suggest that the excitation
energy spectra of an unbound nucleus might reflect the structure of the parent
nucleus from whose fragmentation they are obtained.Comment: Proceedings of the 11th Conference on Problems in Theoretican Nuclear
Physics, Cortona, Italy, 2006. World Scientifi
Hyperpolarizability and operational magic wavelength in an optical lattice clock
Optical clocks benefit from tight atomic confinement enabling extended
interrogation times as well as Doppler- and recoil-free operation. However,
these benefits come at the cost of frequency shifts that, if not properly
controlled, may degrade clock accuracy. Numerous theoretical studies have
predicted optical lattice clock frequency shifts that scale nonlinearly with
trap depth. To experimentally observe and constrain these shifts in an
Yb optical lattice clock, we construct a lattice enhancement cavity
that exaggerates the light shifts. We observe an atomic temperature that is
proportional to the optical trap depth, fundamentally altering the scaling of
trap-induced light shifts and simplifying their parametrization. We identify an
"operational" magic wavelength where frequency shifts are insensitive to
changes in trap depth. These measurements and scaling analysis constitute an
essential systematic characterization for clock operation at the
level and beyond.Comment: 5 + 2 pages, 3 figures, added supplementa
Generation of Ultrastable Microwaves via Optical Frequency Division
There has been increased interest in the use and manipulation of optical
fields to address challenging problems that have traditionally been approached
with microwave electronics. Some examples that benefit from the low
transmission loss, agile modulation and large bandwidths accessible with
coherent optical systems include signal distribution, arbitrary waveform
generation, and novel imaging. We extend these advantages to demonstrate a
microwave generator based on a high-Q optical resonator and a frequency comb
functioning as an optical-to-microwave divider. This provides a 10 GHz
electrical signal with fractional frequency instability <8e-16 at 1 s, a value
comparable to that produced by the best microwave oscillators, but without the
need for cryogenic temperatures. Such a low-noise source can benefit radar
systems, improve the bandwidth and resolution of communications and digital
sampling systems, and be valuable for large baseline interferometry, precision
spectroscopy and the realization of atomic time
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