6,809 research outputs found
Study of perturbed periodic systems of differential equations - The Stroboscopic method
Stroboscopic method for solving perturbed periodic systems of differential equation
The effect of flight line spacing on radioactivity inventory and spatial feature characteristics of airborne gamma-ray spectrometry data
Airborne Gamma Spectrometry (AGS) is well suited to the mapping of radioactivity in the environment. Flight parameters (e.g. speed and line spacing) directly affect the rate of area coverage, cost, and data quality of any survey. The influences of line spacing have been investigated for data from inter‐tidal, coastal and upland environments with a range of <sup>137</sup>Cs activity concentrations and depositional histories. Estimates of the integrated <sup>137</sup>Cs activity (‘inventory’) within specified areas and the shapes of depositional features were calculated for subsets of the data at different line spacings. Features with dimensions greater than the line spacing show variations in inventory and area of less than 3%, and features with dimensions less than the line spacing show larger variations and a decreased probability of detection. The choice of line spacing for a task is dependent on the dimensions of the features of interest and required edge definition. Options for line spacing for different tasks are suggested. It is noted that for regional mapping, even 5–10 km line spacing can produce useful data
Dysfunctional transcripts are formed by alternative polyadenylation in OPMD
Molecular Technology and Informatics for Personalised Medicine and HealthFunctional Genomics of Muscle, Nerve and Brain Disorder
A data-linkage study of suspected seizures in the urgent and emergency care system in the UK
Introduction
The urgent and emergency care system (UEC) is struggling with increased demand, some of which is clinically unnecessary. Patients suffering suspected seizures commonly present to emergency departments, but most seizures are self-limiting and have low risk of short-term adverse outcomes. We aimed to investigate the flow of suspected seizure patients through the UEC system using datalinkage to facilitate development of new models of care.
Methods
We used a two-stage process of deterministic linking to perform a cross-sectional analysis of data from adults in a large region in England (population 5.4 million) during 2014. The core dataset
comprised a total of 739,436 ambulance emergency incidents, 1,033,778 ED attendances and 362,358 admissions.
Results
A high proportion of cases were successfully linked (86.9% ED-inpatient, 77.7% ED-ambulance). Suspected seizures represented 2.8% of all ambulance service incidents. 61.7% of these incidents led to dispatch of a rapid-response ambulance (8 minutes) and 72.1% were conveyed to hospital. 37 patients died before being conveyed to hospital and 24 died in the ED (total 61; 0.3%). The in-patient death rate was 0.4%. Suspected seizures represented 0.71% of ED attendances, 89.8% of these
arrived by emergency ambulance, 45.4% were admitted and 44.5% of these admissions lasted under 48 hours.
Conclusions
This study confirms previously published data from smaller unlinked datasets, validating the linkage method, and provides new data for suspected seizures. There are significant barriers to realising the full potential of data-linkage. Collaborative action is needed to create facilitative governance frameworks and improve data quality and analytical capacity
Effects of QCD Resummation on Distributions of Leptons from the Decay of Electroweak Vector Bosons
We study the distributions of leptons from the decay of electroweak vector
bosons produced in hadron collisions. The effects of the initial state multiple
soft-gluon emission, using the Collins--Soper resummation formalism, are
included. The resummed results are compared with the next-to-leading-order
results for the distributions of the transverse momentum, rapidity asymmetry,
and azimuthal angle of the decay leptons.Comment: 12 pages, 3 figures uuencoded, LaTeX, uses epsf.tex for figures. (Was
replaced on 5/2/95 because of mailer problems.
Mixed-mode oscillations and interspike interval statistics in the stochastic FitzHugh-Nagumo model
We study the stochastic FitzHugh-Nagumo equations, modelling the dynamics of
neuronal action potentials, in parameter regimes characterised by mixed-mode
oscillations. The interspike time interval is related to the random number of
small-amplitude oscillations separating consecutive spikes. We prove that this
number has an asymptotically geometric distribution, whose parameter is related
to the principal eigenvalue of a substochastic Markov chain. We provide
rigorous bounds on this eigenvalue in the small-noise regime, and derive an
approximation of its dependence on the system's parameters for a large range of
noise intensities. This yields a precise description of the probability
distribution of observed mixed-mode patterns and interspike intervals.Comment: 36 page
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