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LGBTQ+ Health-a Novel Course for Undergraduate Students.
The concept of providing focused, competency-based LGBTQ+ health education outside the setting of health professional programs, specifically for undergraduates, is quite uncharted. However, the issue at the core of our rationale is one shared by those with and without clinical exposure: how to best support the development of cultural competence in providers who are or will be caring for LGBTQ+ patients. Traditional health professional education programs have enacted a number of curricular initiatives in this regard, designed for advanced learners. By focusing specifically on the undifferentiated learner, we offer a new perspective on the timing of LGBTQ+ health-related education. Our course is not intended to supplant the critical learning and application that must occur in the clinic or hospital room. Rather, we present a framework for cultivating understanding of the healthcare issues faced by the LGBTQ+ community that may help a learner to acquire and apply skills subsequently with greater cultural competence
The a priori Tan Theta Theorem for spectral subspaces
Let A be a self-adjoint operator on a separable Hilbert space H. Assume that
the spectrum of A consists of two disjoint components s_0 and s_1 such that the
set s_0 lies in a finite gap of the set s_1. Let V be a bounded self-adjoint
operator on H off-diagonal with respect to the partition spec(A)=s_0 \cup s_1.
It is known that if ||V||<\sqrt{2}d, where d=\dist(s_0,s_1), then the
perturbation V does not close the gaps between s_0 and s_1 and the spectrum of
the perturbed operator L=A+V consists of two isolated components s'_0 and s'_1
grown from s_0 and s_1, respectively. Furthermore, it is known that if V
satisfies the stronger bound ||V||< d then the following sharp norm estimate
holds: ||E_L(s'_0)-E_A(s_0)|| \leq sin(arctan(||V||/d)), where E_A(s_0) and
E_L(s'_0) are the spectral projections of A and L associated with the spectral
sets s_0 and s'_0, respectively. In the present work we prove that this
estimate remains valid and sharp also for d \leq ||V||< \sqrt{2}d, which
completely settles the issue.Comment: v3: some typos fixed; Examples adde
Static and Dynamic Properties of Type-II Composite Fermion Wigner Crystals
The Wigner crystal of composite fermions is a strongly correlated state of
complex emergent particles, and therefore its unambiguous detection would be of
significant importance. Recent observation of optical resonances in the
vicinity of filling factor {\nu} = 1/3 has been interpreted as evidence for a
pinned Wigner crystal of composite fermions [Zhu et al., Phys. Rev. Lett. 105,
126803 (2010)]. We evaluate in a microscopic theory the shear modulus and the
magnetophonon and magnetoplasmon dispersions of the composite fermion Wigner
crystal in the vicinity of filling factors 1/3, 2/5, and 3/7. We determine the
region of stability of the crystal phase, and also relate the frequency of its
pinning mode to that of the corresponding electron crystal near integer
fillings. These results are in good semiquantitative agreement with experiment,
and therefore support the identification of the optical resonance as the
pinning mode of the composite fermions Wigner crystal. Our calculations also
bring out certain puzzling features, such as a relatively small melting
temperature for the composite fermion Wigner crystal, and also suggest a higher
asymmetry between Wigner crystals of composite fermion particles and holes than
that observed experimentally.Comment: Composite Fermion Wigner Crystal; 14 pages, 9 figure
AEGIS-X: The Chandra Deep Survey of the Extended Groth Strip
We present the AEGIS-X survey, a series of deep Chandra ACIS-I observations
of the Extended Groth Strip. The survey comprises pointings at 8 separate
positions, each with nominal exposure 200ks, covering a total area of
approximately 0.67 deg2 in a strip of length 2 degrees. We describe in detail
an updated version of our data reduction and point source detection algorithms
used to analyze these data. A total of 1325 band-merged sources have been found
to a Poisson probability limit of 4e-6, with limiting fluxes of 5.3e-17
erg/cm2/s in the soft (0.5-2 keV) band and 3.8e-16 erg/cm2/s in the hard (2-10
keV) band. We present simulations verifying the validity of our source
detection procedure and showing a very small, <1.5%, contamination rate from
spurious sources. Optical/NIR counterparts have been identified from the DEEP2,
CFHTLS, and Spitzer/IRAC surveys of the same region. Using a likelihood ratio
method, we find optical counterparts for 76% of our sources, complete to
R(AB)=24.1, and, of the 66% of the sources that have IRAC coverage, 94% have a
counterpart to a limit of 0.9 microJy at 3.6 microns (m(AB)=23.8). After
accounting for (small) positional offsets in the 8 Chandra fields, the
astrometric accuracy of the Chandra positions is found to be 0.8 arcsec RMS,
however this number depends both on the off-axis angle and the number of
detected counts for a given source. All the data products described in this
paper are made available via a public website.Comment: 17 pages, 9 figures. Accepted for publication in ApJS. Data products
are available at http://astro.imperial.ac.uk/research/aegis
Donor-specific Cell-based Assays in Studying Sensitivity to Low-dose Radiation: A Population-based Perspective
Currently, a linear no-threshold model is used to estimate health risks associated with exposure to low-dose radiation, a prevalent exposure in the general population, because the direct estimation from epidemiological studies suffers from uncertainty. This model has been criticized based on unique biology of low-dose radiation. Whether the departure from linearity is toward increased or decreased risk is intensely debated. We present an approach based on individual radiosensitivity testing and discuss how individual radiosensitivity can be assessed with the goal to develop a quantifiable measure of cellular response that can be conducted via high-throughput population testing
Quantum tunneling of superconducting string currents
We investigate the decay of current on a superconducting cosmic string
through quantum tunneling. We construct the instanton describing tunneling in a
simple bosonic string model, and estimate the decay rate. The tunneling rate
vanishes in the limit of a chiral current. This conclusion, which is supported
by a symmetry argument, is expected to apply in general. It has important
implications for the stability of chiral vortons.Comment: 16 pages, 2 figure
Wind Tunnel Results of the B-52B with the X-43A Stack
A low-speed wind-tunnel test was performed with a three-percent-scale model of a booster rocket mated to an X-43A research vehicle, a combination referred to as the Hyper-X launch vehicle. The test was conducted both in free-stream air and in the presence of a partial model of the B-52B airplane. The objectives of the test were to obtain force and moment data to generate structural loads affecting the pylon of the B-52B airplane and to determine the aerodynamic influence of the B-52B airplane on the Hyper-X launch vehicle to evaluate launch separation characteristics. The wind-tunnel test was conducted at a low-speed wind tunnel in Hampton, Virginia. All moments and forces reported are based either on the aerodynamic influence of the B-52B airplane or are for the Hyper-X launch vehicle in free-stream air. Overall, the test showed that the B-52B airplane imparts a strong downwash onto the Hyper-X launch vehicle, reducing the net lift of the Hyper-X launch vehicle. Also, pitching and rolling moments are imparted onto the booster and are a strong function of the launch-drop angle of attack
Bogoliubov angle and visualization of particle-hole mixture in superconductors
Superconducting excitations --Bogoliubov quasiparticles -- are the quantum
mechanical mixture of negatively charged electron (-e) and positively charged
hole (+e). Depending on the applied voltage bias in STM one can sample the
particle and hole content of such a superconducting excitation. Recent Scanning
Tunneling Microscope (STM) experiments offer a unique insight into the inner
workings of the superconducting state of superconductors. We propose a new
observable quantity for STM studies that is the manifestation of the
particle-hole dualism of the quasiparticles. We call it a {\em Bogoliubov
angle}. This angle measures the relative weight of particle and hole amplitude
in the superconducting (Bogoliubov) quasiparticle. We argue that this quantity
can be measured locally by comparing the ratio of tunneling currents at
positive and negative biases. This Bogoliubov angle allows one to measure
directly the energy and position dependent particle-hole admixture and
therefore visualize robustness of superconducting state locally. It may also
allow one to measure the particle-hole admixture of excitations in normal state
above critical temperature and thus may be used to measure superconducting
correlations in pseudogap state.Comment: 16 pages, latex file, 9 eps figure
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