132 research outputs found
Task Shifting: The Use of Laypersons for Acquisition of Vital Signs Data for Clinical Decision Making in the Emergency Room Following Traumatic Injury
Importance: In resource-limited settings, identification of successful and sustainable task-shifting interventions is important for improving care. Objective: To determine whether the training of lay people to take vital signs as trauma clerks is an effective and sustainable method to increase availability of vital signs in the initial evaluation of trauma patients. Design: We conducted a quasi-experimental study of patients presenting with traumatic injury pre- and post-intervention. Setting: The study was conducted at Kamuzu Central Hospital, a tertiary care referral hospital, in Lilongwe, Malawi. Participants: All adult (age ≥ 18 years) trauma patients presenting to emergency department over a six-month period from January to June prior to intervention (2011), immediately post-intervention (2012), 1 year post-intervention (2013) and 2 years post-intervention (2014). Intervention: Lay people were trained to take and record vital signs. Main outcomes and measures: The number of patients with recorded vital signs pre- and post-intervention and sustainability of the intervention as determined by time-series analysis. Results: Availability of vital signs on initial evaluation of trauma patients increased significantly post-intervention. The percentage of patients with at least one vital sign recorded increased from 23.5 to 92.1%, and the percentage of patients with all vital signs recorded increased from 4.1 to 91.4%. Availability of Glasgow Coma Scale also increased from 40.3 to 88.6%. Increased documentation of vital signs continued at 1 year and 2 years post-intervention. However, the percentage of documented vital signs did decrease slightly after the US-trained medical student and surgeon who trained the trauma clerks were no longer available in country, except for Glasgow Coma Scale. Patients who died during emergency department evaluation were significantly less likely to have vital signs recorded. Conclusions and relevance: The training of lay people to collect vital signs and Glasgow Coma Scale is an effective and sustainable method of task shifting in a resource-limited setting
Injury Characteristics and Outcomes in Elderly Trauma Patients in Sub-Saharan Africa
Background: Traumatic injury in the elderly is an emerging global problem with an associated increase in morbidity and mortality. This study sought to describe the epidemiology of elderly injury and outcomes in sub-Saharan Africa. Methods: We conducted a retrospective analysis of adult patients (≥ 18 years) with traumatic injuries presenting to the Kamuzu Central Hospital (KCH) in Lilongwe, Malawi, over 5 years (2009–2013). Elderly patients were defined as adults aged ≥65 years and compared to adults aged 18–44 and 45–64 years. We used propensity score matching and logistic regression to compare the odds of mortality between age groups using the youngest age group as the reference. Results: 42,816 Adult patients with traumatic injuries presented to KCH during the study period. 1253 patients (2.9 %) were aged ≥65 years with a male preponderance (77.4 %). Injuries occurred more often at home as age increased (25.3, 29.5, 41.1 %, p < 0.001) and falls were more common (14.1, 23.8, 36.3 %, p < 0.001) for elderly patients. Elderly age was associated with a higher proportion of hospital admissions (10.6, 21.3, 35.2 %, p < 0.001). Upon propensity score matching and logistic regression analysis, the odds ratio of mortality for patients aged ≥65 was 3.15 (95 % CI 1.45, 6.82, p = 0.0037) compared to the youngest age group (18–44 years). Conclusions: Elderly trauma in a resource-poor area in sub-Saharan Africa is associated with a significant increase in hospital admissions and mortality. Significant improvements in trauma systems, pre-hospital care, and hospital capacity for older, critically ill patients are imperative
The ground state energy of the Edwards-Anderson spin glass model with a parallel tempering Monte Carlo algorithm
We study the efficiency of parallel tempering Monte Carlo technique for
calculating true ground states of the Edwards-Anderson spin glass model.
Bimodal and Gaussian bond distributions were considered in two and
three-dimensional lattices. By a systematic analysis we find a simple formula
to estimate the values of the parameters needed in the algorithm to find the GS
with a fixed average probability. We also study the performance of the
algorithm for single samples, quantifying the difference between samples where
the GS is hard, or easy, to find. The GS energies we obtain are in good
agreement with the values found in the literature. Our results show that the
performance of the parallel tempering technique is comparable to more powerful
heuristics developed to find the ground state of Ising spin glass systems.Comment: 30 pages, 17 figures. A new section added. Accepted for publication
in Physica
The Approach to Ergodicity in Monte Carlo Simulations
The approach to the ergodic limit in Monte Carlo simulations is studied using
both analytic and numerical methods. With the help of a stochastic model, a
metric is defined that enables the examination of a simulation in both the
ergodic and non-ergodic regimes. In the non-ergodic regime, the model implies
how the simulation is expected to approach ergodic behavior analytically, and
the analytically inferred decay law of the metric allows the monitoring of the
onset of ergodic behavior. The metric is related to previously defined measures
developed for molecular dynamics simulations, and the metric enables the
comparison of the relative efficiencies of different Monte Carlo schemes.
Applications to Lennard-Jones 13-particle clusters are shown to match the model
for Metropolis, J-walking and parallel tempering based approaches. The relative
efficiencies of these three Monte Carlo approaches are compared, and the decay
law is shown to be useful in determining needed high temperature parameters in
parallel tempering and J-walking studies of atomic clusters.Comment: 17 Pages, 7 Figure
Magnetic Catalysis: A Review
We give an overview of the magnetic catalysis phenomenon. In the framework of
quantum field theory, magnetic catalysis is broadly defined as an enhancement
of dynamical symmetry breaking by an external magnetic field. We start from a
brief discussion of spontaneous symmetry breaking and the role of a magnetic
field in its a dynamics. This is followed by a detailed presentation of the
essential features of the phenomenon. In particular, we emphasize that the
dimensional reduction plays a profound role in the pairing dynamics in a
magnetic field. Using the general nature of underlying physics and its
robustness with respect to interaction types and model content, we argue that
magnetic catalysis is a universal and model-independent phenomenon. In support
of this claim, we show how magnetic catalysis is realized in various models
with short-range and long-range interactions. We argue that the general nature
of the phenomenon implies a wide range of potential applications: from certain
types of solid state systems to models in cosmology, particle and nuclear
physics. We finish the review with general remarks about magnetic catalysis and
an outlook for future research.Comment: 37 pages, to appear in Lect. Notes Phys. "Strongly interacting matter
in magnetic fields" (Springer), edited by D. Kharzeev, K. Landsteiner, A.
Schmitt, H.-U. Yee. Version 2: references adde
Measurement of Atmospheric Neutrino Oscillations with the ANTARES Neutrino Telescope
The data taken with the ANTARES neutrino telescope from 2007 to 2010, a total
live time of 863 days, are used to measure the oscillation parameters of
atmospheric neutrinos. Muon tracks are reconstructed with energies as low as 20
GeV. Neutrino oscillations will cause a suppression of vertical upgoing muon
neutrinos of such energies crossing the Earth. The parameters determining the
oscillation of atmospheric neutrinos are extracted by fitting the event rate as
a function of the ratio of the estimated neutrino energy and reconstructed
flight path through the Earth. Measurement contours of the oscillation
parameters in a two-flavour approximation are derived. Assuming maximum mixing,
a mass difference of eV is
obtained, in good agreement with the world average value.Comment: 9 pages, 5 figure
A First Search for coincident Gravitational Waves and High Energy Neutrinos using LIGO, Virgo and ANTARES data from 2007
We present the results of the first search for gravitational wave bursts
associated with high energy neutrinos. Together, these messengers could reveal
new, hidden sources that are not observed by conventional photon astronomy,
particularly at high energy. Our search uses neutrinos detected by the
underwater neutrino telescope ANTARES in its 5 line configuration during the
period January - September 2007, which coincided with the fifth and first
science runs of LIGO and Virgo, respectively. The LIGO-Virgo data were analysed
for candidate gravitational-wave signals coincident in time and direction with
the neutrino events. No significant coincident events were observed. We place
limits on the density of joint high energy neutrino - gravitational wave
emission events in the local universe, and compare them with densities of
merger and core-collapse events.Comment: 19 pages, 8 figures, science summary page at
http://www.ligo.org/science/Publication-S5LV_ANTARES/index.php. Public access
area to figures, tables at
https://dcc.ligo.org/cgi-bin/DocDB/ShowDocument?docid=p120000
Whole genome analysis of a schistosomiasis-transmitting freshwater snail
Biomphalaria snails are instrumental in transmission of the human blood fluke Schistosoma mansoni. With the World Health Organization's goal to eliminate schistosomiasis as a global health problem by 2025, there is now renewed emphasis on snail control. Here, we characterize the genome of Biomphalaria glabrata, a lophotrochozoan protostome, and provide timely and important information on snail biology. We describe aspects of phero-perception, stress responses, immune function and regulation of gene expression that support the persistence of B. glabrata in the field and may define this species as a suitable snail host for S. mansoni. We identify several potential targets for developing novel control measures aimed at reducing snail-mediated transmission of schistosomiasis
Searches for clustering in the time integrated skymap of the ANTARES neutrino telescope
This paper reports a search for spatial clustering of the arrival directions of high energy muon neutrinos detected by the ANTARES neutrino telescope. An improved two-point correlation method is used to study the autocorrelation of 3058 neutrino candidate events as well as cross-correlations with other classes of astrophysical objects: sources of high energy gamma rays, massive black holes and nearby galaxies. No significant deviations from the isotropic distribution of arrival directions expected from atmospheric backgrounds are observed
- …