1,190 research outputs found
The Many Faces of Lyme Disease
Lyme disease is the most common vector-borne disease in the United States today, and cases
continue to grow every year. Lyme disease can be challenging to diagnose due to the many
presenting symptoms. This independent study is meant to describe symptoms of Lyme Jess
traditionally discussed in medical and nursing literature when considering how and when to
~ diagnose Lyme disease. It is also meant to examine common diagnostic problems in pediatric,
maternal, and elderly populations. This was accomplished with the use of a literature review, ~ resulting in the development of a white paper and educational brochure for dissemination to the health care providers and the general public. Lyme disease presents without the well-known
bull\u27s eye rash more often than providers may suspect. In some endemic areas, the most
common reason for a presenting complaint of meningitis, arthritis or facial palsies in children is
the Lyme bacteria. Elderly patients may present with neurological symptoms of Lyme disease ~that are mistaken for other neurological diagnoses. Treating these complaints with common
antibiotics and other treatments may not correctly treat Lyme disease. Therefore, health care
providers and patients need to be aware of these different symptoms to avoid delayed diagnosis
and unnecessary or costly treatments. The literature review was limited by the limited amount of
studies that focus on this particular topic. Pieces that were included focused on symptoms of
Lyme other than erythema migraine
Clinical features of alcoholic hepatitis in latinos and caucasians: A single center experience.
AimTo study differences of presentation, management, and prognosis of alcoholic hepatitis in Latinos compared to Caucasians.MethodsWe retrospectively screened 876 charts of Caucasian and Latino patients who were evaluated at University of California Davis Medical Center between 1/1/2002-12/31/2014 with the diagnosis of alcoholic liver disease. We identified and collected data on 137 Caucasians and 64 Latinos who met criteria for alcoholic hepatitis, including chronic history of heavy alcohol use, at least one episode of jaundice with bilirubin ≥ 3.0 or coagulopathy, new onset of liver decompensation or acute liver decompensation in known cirrhosis within 12 wk of last drink.ResultsThe mean age at presentation of alcoholic hepatitis was not significantly different between Latinos and Caucasians. There was significant lower rate of overall substance abuse in Caucasians compared to Latinos and Latinos had a higher rate of methamphetamine abuse (12.5% vs 0.7%) compared to Caucasians. Latinos had a higher mean number of hospitalizations (5.3 ± 5.6 vs 2.7 ± 2.7, P = 0.001) and mean Emergency Department visits (9.5 ± 10.8 vs 4.5 ± 4.1, P = 0.017) for alcohol related issues and complications compared to Caucasians. There was significantly higher rate of complications of portal hypertension including gastrointestinal bleeding (79.7% vs 45.3%, P < 0.001), spontaneous bacterial peritonitis (26.6% vs 9.5%, P = 0.003), and encephalopathy (81.2% vs 55.5%, P = 0.001) in Latinos compared to Caucasians.ConclusionLatinos have significant higher rates of utilization of acute care services for manifestations alcoholic hepatitis and complications suggesting poor access to outpatient care
Relaxation time in a non-conserving driven-diffusive system with parallel dynamics
We introduce a two-state non-conserving driven-diffusive system in
one-dimension under a discrete-time updating scheme. We show that the
steady-state of the system can be obtained using a matrix product approach. On
the other hand, the steady-state of the system can be expressed in terms of a
linear superposition Bernoulli shock measures with random walk dynamics. The
dynamics of a shock position is studied in detail. The spectrum of the transfer
matrix and the relaxation times to the steady-state have also been studied in
the large-system-size limit.Comment: 10 page
Noise-induced dynamical transition in systems with symmetric absorbing states
We investigate the effect of noise strength on the macroscopic ordering
dynamics of systems with symmetric absorbing states. Using an explicit
stochastic microscopic model, we present evidence for a phase transition in the
coarsening dynamics, from an Ising-like to a voter-like behavior, as the noise
strength is increased past a nontrivial critical value. By mapping to a thermal
diffusion process, we argue that the transition arises due to locally-absorbing
states being entered more readily in the high-noise regime, which in turn
prevents surface tension from driving the ordering process.Comment: v2 with improved introduction and figures, to appear in PRL. 4 pages,
4 figure
Shock in a Branching-Coalescing Model with Reflecting Boundaries
A one-dimensional branching-coalescing model is considered on a chain of
length L with reflecting boundaries. We study the phase transitions of this
model in a canonical ensemble by using the Yang-Lee description of the
non-equilibrium phase transitions. Numerical study of the canonical partition
function zeros reveals two second-order phase transitions in the system. Both
transition points are determined by the density of the particles on the chain.
In some regions the density profile of the particles has a shock structure.Comment: Contents modified and new references added, to appear in Physics
Letters
Dyck Paths, Motzkin Paths and Traffic Jams
It has recently been observed that the normalization of a one-dimensional
out-of-equilibrium model, the Asymmetric Exclusion Process (ASEP) with random
sequential dynamics, is exactly equivalent to the partition function of a
two-dimensional lattice path model of one-transit walks, or equivalently Dyck
paths. This explains the applicability of the Lee-Yang theory of partition
function zeros to the ASEP normalization.
In this paper we consider the exact solution of the parallel-update ASEP, a
special case of the Nagel-Schreckenberg model for traffic flow, in which the
ASEP phase transitions can be intepreted as jamming transitions, and find that
Lee-Yang theory still applies. We show that the parallel-update ASEP
normalization can be expressed as one of several equivalent two-dimensional
lattice path problems involving weighted Dyck or Motzkin paths. We introduce
the notion of thermodynamic equivalence for such paths and show that the
robustness of the general form of the ASEP phase diagram under various update
dynamics is a consequence of this thermodynamic equivalence.Comment: Version accepted for publicatio
Single microwave photon detection in the micromaser
High efficiency single photon detection is an interesting problem for many
areas of physics, including low temperature measurement, quantum information
science and particle physics. For optical photons, there are many examples of
devices capable of detecting single photons with high efficiency. However
reliable single photon detection of microwaves is very difficult, principally
due to their low energy. In this paper we present the theory of a cascade
amplifier operating in the microwave regime that has an optimal quantum
efficiency of 93%. The device uses a microwave photon to trigger the stimulated
emission of a sequence of atoms where the energy transition is readily
detectable. A detailed description of the detector's operation and some
discussion of the potential limitations of the detector are presented.Comment: 8 pages, 5 figure
Free energy landscapes, dynamics and the edge of chaos in mean-field models of spin glasses
Metastable states in Ising spin-glass models are studied by finding iterative
solutions of mean-field equations for the local magnetizations. Two different
equations are studied: the TAP equations which are exact for the SK model, and
the simpler `naive-mean-field' (NMF) equations. The free-energy landscapes that
emerge are very different. For the TAP equations, the numerical studies confirm
the analytical results of Aspelmeier et al., which predict that TAP states
consist of close pairs of minima and index-one (one unstable direction) saddle
points, while for the NMF equations saddle points with large indices are found.
For TAP the barrier height between a minimum and its nearby saddle point scales
as (f-f_0)^{-1/3} where f is the free energy per spin of the solution and f_0
is the equilibrium free energy per spin. This means that for `pure states', for
which f-f_0 is of order 1/N, the barriers scale as N^{1/3}, but between states
for which f-f_0 is of order one the barriers are finite and also small so such
metastable states will be of limited physical significance. For the NMF
equations there are saddles of index K and we can demonstrate that their
complexity Sigma_K scales as a function of K/N. We have also employed an
iterative scheme with a free parameter that can be adjusted to bring the system
of equations close to the `edge of chaos'. Both for the TAP and NME equations
it is possible with this approach to find metastable states whose free energy
per spin is close to f_0. As N increases, it becomes harder and harder to find
solutions near the edge of chaos, but nevertheless the results which can be
obtained are competitive with those achieved by more time-consuming computing
methods and suggest that this method may be of general utility.Comment: 13 page
Exact Solution of a Reaction-Diffusion Model with Particle Number Conservation
We analytically investigate a 1d branching-coalescing model with reflecting
boundaries in a canonical ensemble where the total number of particles on the
chain is conserved. Exact analytical calculations show that the model has two
different phases which are separated by a second-order phase transition. The
thermodynamic behavior of the canonical partition function of the model has
been calculated exactly in each phase. Density profiles of particles have also
been obtained explicitly. It is shown that the exponential part of the density
profiles decay on three different length scales which depend on total density
of particles.Comment: 7 pages, REVTEX4, Contents updated and new references added, to
appear in Physical Review
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