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Assessment of sexual difficulties associated with multi-modal treatment for cervical or endometrial cancer: A systematic review of measurement instruments
Background: Practitioners and researchers require an outcome measure that accurately identifies the range of common treatment-induced changes in sexual function and well-being experienced by women after cervical or endometrial cancer. This systematic review critically appraised the measurement properties and clinical utility of instruments validated for the measurement of female sexual dysfunction (FSD) in this clinical population.
Methods: A bibliographic database search for questionnaire development or validation papers was completed and methodological quality and measurement properties of selected studies rated using the Consensus-based Standards for the selection of health Measurement Instrument (COSMIN) checklist.
Results: 738 articles were screened, 13 articles retrieved for full text assessment and 7 studies excluded, resulting in evaluation of 6 papers; 2 QoL and 4 female sexual morbidity measures.
Five of the six instruments omitted one or more dimension of female sexual function and only one instrument explicitly measured distress associated with sexual changes as per DSM V (APA 2013) diagnostic criteria.
None of the papers reported measurement error, responsiveness data was available for only two instruments, three papers failed to report on criterion validity, and test-retest reliability reporting was inconsistent. Heterosexual penile-vaginal intercourse remains the dominant sexual activity focus for sexual morbidity PROMS terminology and instruments lack explicit reference to solo or non-coital sexual expression or validation in a non-heterosexual sample. Four out of six instruments included mediating treatment or illness items such as vaginal changes, menopause or altered body image.
Conclusions: Findings suggest that the Female Sexual Function Index (FSFI) remains the most robust sexual morbidity outcome measure, for research or clinical use, in sexually active women treated for cervical or endometrial cancer
A new energy upper bound for AdS black holes inspired by free field theory
We consider the toroidally compactified planar AdS-Schwarzschild solution to 4-dimensional gravity with negative cosmological constant. This has a flat torus conformal boundary metric. We show that if the spatial part of the boundary metric is deformed, keeping it static and the temperature and area fixed, then assuming a static bulk solution exists, its energy is less than that of the AdS-Schwarzschild solution. The proof is non-perturbative in the metric deformation. While we expect the same holds for the free energy for black hole solutions we are so far are not able to prove it. In the context of AdS-CFT this implies a 3-dimensional holographic CFT on a flat spatial torus whose bulk dual is AdS-Schwarzschild has a greater energy than if the spatial geometry is deformed in any way that preserves temperature and area. This work was inspired by previous results in free field theory, where scalars and fermions in 3-dimensions have been shown to energetically disfavour flat space
Heterodyne and adaptive phase measurements on states of fixed mean photon number
The standard technique for measuring the phase of a single mode field is
heterodyne detection. Such a measurement may have an uncertainty far above the
intrinsic quantum phase uncertainty of the state. Recently it has been shown
[H. M. Wiseman and R. B. Killip, Phys. Rev. A 57, 2169 (1998)] that an adaptive
technique introduces far less excess noise. Here we quantify this difference by
an exact numerical calculation of the minimum measured phase variance for the
various schemes, optimized over states with a fixed mean photon number. We also
analytically derive the asymptotics for these variances. For the case of
heterodyne detection our results disagree with the power law claimed by
D'Ariano and Paris [Phys. Rev. A 49, 3022 (1994)].Comment: 9 pages, 2 figures, minor changes from journal versio
From Black Strings to Black Holes
Using recently developed numerical methods, we examine neutral compactified
non-uniform black strings which connect to the Gregory-Laflamme critical point.
By studying the geometry of the horizon we give evidence that this branch of
solutions may connect to the black hole solutions, as conjectured by Kol. We
find the geometry of the topology changing solution is likely to be nakedly
singular at the point where the horizon radius is zero. We show that these
solutions can all be expressed in the coordinate system discussed by Harmark
and Obers.Comment: 6 pages, 5 figures, RevTe
Adaptive single-shot phase measurements: The full quantum theory
The phase of a single-mode field can be measured in a single-shot measurement
by interfering the field with an effectively classical local oscillator of
known phase. The standard technique is to have the local oscillator detuned
from the system (heterodyne detection) so that it is sometimes in phase and
sometimes in quadrature with the system over the course of the measurement.
This enables both quadratures of the system to be measured, from which the
phase can be estimated. One of us [H.M. Wiseman, Phys. Rev. Lett. 75, 4587
(1995)] has shown recently that it is possible to make a much better estimate
of the phase by using an adaptive technique in which a resonant local
oscillator has its phase adjusted by a feedback loop during the single-shot
measurement. In Ref.~[H.M. Wiseman and R.B. Killip, Phys. Rev. A 56, 944] we
presented a semiclassical analysis of a particular adaptive scheme, which
yielded asymptotic results for the phase variance of strong fields. In this
paper we present an exact quantum mechanical treatment. This is necessary for
calculating the phase variance for fields with small photon numbers, and also
for considering figures of merit other than the phase variance. Our results
show that an adaptive scheme is always superior to heterodyne detection as far
as the variance is concerned. However the tails of the probability distribution
are surprisingly high for this adaptive measurement, so that it does not always
result in a smaller probability of error in phase-based optical communication.Comment: 17 pages, LaTeX, 8 figures (concatenated), Submitted to Phys. Rev.
Phonon number quantum jumps in an optomechanical system
We describe an optomechanical system in which the mean phonon number of a
single mechanical mode conditionally displaces the amplitude of the optical
field. Using homodyne detection of the output field we establish the conditions
under which phonon number quantum jumps can be inferred from the measurement
record: both the cavity damping rate and the measurement rate of the phonon
number must be much greater than the thermalization rate of the mechanical
mode. We present simulations of the conditional dynamics of the measured system
using the stochastic master equation. In the good-measurement limit, the
conditional evolution of the mean phonon number shows quantum jumps as phonons
enter and exit the mechanical resonator via the bath.Comment: 13 pages, 4 figures. minor revisions since first versio
Static Axisymmetric Vacuum Solutions and Non-Uniform Black Strings
We describe new numerical methods to solve the static axisymmetric vacuum
Einstein equations in more than four dimensions. As an illustration, we study
the compactified non-uniform black string phase connected to the uniform
strings at the Gregory-Laflamme critical point. We compute solutions with a
ratio of maximum to minimum horizon radius up to nine. For a fixed
compactification radius, the mass of these solutions is larger than the mass of
the classically unstable uniform strings. Thus they cannot be the end state of
the instability.Comment: 48 pages, 13 colour figures; v2: references correcte
On Black-Brane Instability In an Arbitrary Dimension
The black-hole black-string system is known to exhibit critical dimensions
and therefore it is interesting to vary the spacetime dimension , treating
it as a parameter of the system. We derive the large asymptotics of the
critical, i.e. marginally stable, string following an earlier numerical
analysis. For a background with an arbitrary compactification manifold we give
an expression for the critical mass of a corresponding black brane. This
expression is completely explicit for , the dimensional torus of
an arbitrary shape. An indication is given that by employing a higher
dimensional torus, rather than a single compact dimension, the total critical
dimension above which the nature of the black-brane black-hole phase transition
changes from sudden to smooth could be as low as .Comment: 1+14 pages, 2 eps figures. Replaced with the published versio
Weak Values, Quantum Trajectories, and the Stony-Brook Cavity QED experiment
Weak values as introduced by Aharonov, Albert and Vaidman (AAV) are ensemble
average values for the results of weak measurements. They are interesting when
the ensemble is preselected on a particular initial state and postselected on a
particular final measurement result. I show that weak values arise naturally in
quantum optics, as weak measurements occur whenever an open system is monitored
(as by a photodetector). I use quantum trajectory theory to derive a
generalization of AAV's formula to include (a) mixed initial conditions, (b)
nonunitary evolution, (c) a generalized (non-projective) final measurement, and
(d) a non-back-action-evading weak measurement. I apply this theory to the
recent Stony-Brook cavity QED experiment demonstrating wave-particle duality
[G.T. Foster, L.A. Orozco, H.M. Castro-Beltran, and H.J. Carmichael, Phys. Rev.
Lett. {85}, 3149 (2000)]. I show that the ``fractional'' correlation function
measured in that experiment can be recast as a weak value in a form as simple
as that introduced by AAV.Comment: 6 pages, no figures. To be published in Phys. Rev.
The Uncertainty Relation in "Which-Way" Experiments: How to Observe Directly the Momentum Transfer using Weak Values
A which-way measurement destroys the twin-slit interference pattern. Bohr
argued that distinguishing between two slits a distance s apart gives the
particle a random momentum transfer \wp of order h/s. This was accepted for
more than 60 years, until Scully, Englert and Walther (SEW) proposed a
which-way scheme that, they claimed, entailed no momentum transfer. Storey,
Tan, Collett and Walls (STCW) in turn proved a theorem that, they claimed,
showed that Bohr was right. This work reviews and extends a recent proposal
[Wiseman, Phys. Lett. A 311, 285 (2003)] to resolve the issue using a
weak-valued probability distribution for momentum transfer, P_wv(\wp). We show
that P_wv(\wp) must be wider than h/6s. However, its moments can still be zero
because P_wv(\wp) is not necessarily positive definite. Nevertheless, it is
measurable in a way understandable to a classical physicist. We introduce a new
measure of spread for P_wv(\wp): half of the unit-confidence interval, and
conjecture that it is never less than h/4s. For an idealized example with
infinitely narrow slits, the moments of P_wv(\wp) and of the momentum
distributions are undefined unless a process of apodization is used. We show
that by considering successively smoother initial wave functions, successively
more moments of both P_wv(\wp) and the momentum distributions become defined.
For this example the moments of P_wv(\wp) are zero, and these are equal to the
changes in the moments of the momentum distribution. We prove that this
relation holds for schemes in which the moments of P_wv(\wp) are non-zero, but
only for the first two moments. We also compare these moments to those of two
other momentum-transfer distributions and \hat{p}_f-\hat{p}_i. We find
agreement between all of these, but again only for the first two moments.Comment: 14 pages, 6 figures, submitted to J. Opt.
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