Early Seizure Detection Based on Cardiac Autonomic Regulation Dynamics

Epilepsy is a neurological disorder that causes changes in the autonomic nervous system. Heart rate variability (HRV) reflects the regulation of cardiac activity and autonomic nervous system tone. The early detection of epileptic seizures could foster the use of new treatment approaches. This study presents a new methodology for the prediction of epileptic seizures using HRV signals. Eigendecomposition of HRV parameter covariance matrices was used to create an input for a support vector machine (SVM)-based classifier. We analyzed clinical data from 12 patients (9 female; 3 male; age 34.5 ± 7.5 years), involving 34 seizures and a total of 55.2 h of interictal electrocardiogram (ECG) recordings. Data from 123.6 h of ECG recordings from healthy subjects were used to test false positive rate per hour (FP/h) in a completely independent data set. Our methodological approach allowed the detection of impending seizures from 5 min to just before the onset of a clinical/electrical seizure with a sensitivity of 94.1%. The FP rate was 0.49 h−1 in the recordings from patients with epilepsy and 0.19 h−1 in the recordings from healthy subjects. Our results suggest that it is feasible to use the dynamics of HRV parameters for the early detection and, potentially, the prediction of epileptic seizures

Data augmentation using generative networks to identify dementia

Data limitation is one of the most common issues in training machine learning classifiers for medical applications. Due to ethical concerns and data privacy, the number of people that can be recruited to such experiments is generally smaller than the number of participants contributing to non-healthcare datasets. Recent research showed that generative models can be used as an effective approach for data augmentation, which can ultimately help to train more robust classifiers sparse data domains. A number of studies proved that this data augmentation technique works for image and audio data sets. In this paper, we investigate the application of a similar approach to different types of speech and audio-based features extracted from interactions recorded with our automatic dementia detection system. Using two generative models we show how the generated synthesized samples can improve the performance of a DNN based classifier. The variational autoencoder increased the F-score of a four-way classifier distinguishing the typical patient groups seen in memory clinics from 58% to around 74%, a 16% improvement

What Does Free Space Lambda-Lambda Interaction Predict for Lambda-Lambda Hypernuclei?

Data on Lambda-Lambda hypernuclei provide a unique method to learn details on the strangeness S =-2 sector of the baryon-baryon interaction. From the free space Bonn-Julich potentials, determined from data on baryon-baryon scattering in the S=0,-1 channels, we construct an interaction in the S =-2 sector to describe the experimentally known Lambda-Lambda hypernuclei. After including short--range (Jastrow) and RPA correlations, we find masses for these Lambda-Lambda hypernuclei in a reasonable agreement with data, taking into account theoretical and experimental uncertainties. Thus, we provide a natural extension, at low energies, of the Bonn-Julich OBE potentials to the S =-2 channel.Comment: 4 pages, 2 figures, revtex4 style. Minor changes in conclusions. References updated. Accepted in Phys. Rev. Let

Economic liberalization and the antecedents of top management teams: evidence from Turkish 'big' business

There has been an increased interest in the last two decades in top management teams (TMTs) of business firms. Much of the research, however, has been US-based and concerned primarily with TMT effects on organizational outcomes. The present study aims to expand this literature by examining the antecedents of top team composition in the context of macro-level economic change in a late-industrializing country. The post-1980 trade and market reforms in Turkey provided the empirical setting. Drawing upon the literatures on TMT and chief executive characteristics together with punctuated equilibrium models of change and institutional theory, the article develops the argument that which firm-level factors affect which attributes of TMT formations varies across the early and late stages of economic liberalization. Results of the empirical investigation of 71 of the largest industrial firms in Turkey broadly supported the hypotheses derived from this premise. In the early stages of economic liberalization the average age and average organizational tenure of TMTs were related to the export orientation of firms, whereas in later stages, firm performance became a major predictor of these team attributes. Educational background characteristics of teams appeared to be under stronger institutional pressures, altering in different ways in the face of macro-level change

Pion-Lambda-Sigma Coupling Extracted from Hyperonic Atoms

The latest measurements of the atomic level width in Sigma-hyperonic Pb atom offer the most accurate datum in the region of low-energy Sigma-hyperon physics. Atomic widths are due to the conversion of Sigma-nucleon into Lambda-nucleon. In high angular momentum states this conversion is dominated by the one-pion exchange. A joint analysis of the data of the scattering of negative-Sigma on proton converting into a Lambda and a neutron and of the atomic widths allows to extract a pseudovector pion-hyperon-Sigma coupling constant of 0.048 with a statistical error of +-0.005 and a systematic one of +-0.004. This corresponds to a pseudoscalar coupling constant of 13.3 with a statistical uncertainty of 1.4 and a systematic one of 1.1.Comment: 12 pages, 1 figure, Use of Revtex.st

The hyperon-nucleon interaction: conventional versus effective field theory approach

Hyperon-nucleon interactions are presented that are derived either in the conventional meson-exchange picture or within leading order chiral effective field theory. The chiral potential consists of one-pseudoscalar-meson exchanges and non-derivative four-baryon contact terms. With regard to meson-exchange hyperon-nucleon models we focus on the new potential of the Juelich group, whose most salient feature is that the contributions in the scalar--isoscalar (\sigma) and vector--isovector (\rho) exchange channels are constrained by a microscopic model of correlated \pi\pi and KKbar exchange.Comment: 28 pages, 8 figures, submitted to Lecture Notes in Physic

SS-matrix poles near the ΛN\Lambda N and ΣN\Sigma N Thresholds in the Coupled \\ΛN−ΣN\Lambda N-\Sigma N System

We search $t$-matrix poles for $\Lambda N-\Sigma N$ coupling interactions using two soft core models of the Nijmegen group which bind the hypertriton at the correct binding energy, and hard core models which are still influential in hypernuclear physics. To treat the hard core potentials, a useful method for calculating the off-shell $t$-matrix is proposed. We find poles close to the $\Sigma N$ threshold in the second or third quadrant of the complex plane of the $\Sigma N$ relative momentum. The relation between the poles and the shape of the $\Lambda N$ elastic total cross section is discussed based on a so-called uniformization by which two-channel $t$-matrices become single-valued on a complex valuable. We also find poles near the $\Lambda N$ threshold. These are correlated to the $S$-wave $\Lambda N$ scattering lengths, the values of which have yet to be determined.Comment: 18 pages, 7 figures, Revte

Oro-mucosal midazolam maleate: Use and effectiveness in adults with epilepsy in the UK.

BACKGROUND: Oro-mucosal midazolam maleate (OMM) with suitable training to family and carers is being increasingly recognized as the treatment of choice to mitigate the development of status epilepticus in non-hospital community settings. There are no studies to describe the use, effectiveness, and suitable dosing of OMM in adults with epilepsy in community settings. PURPOSE: To describe the use, effectiveness, and dosing of OMM in the emergency treatment of epileptic seizures in community settings. METHODS: A retrospective observational study (2016-17) design was used with participant recruitment from four UK NHS secondary care outpatient clinics providing epilepsy management. Study sample was of adult people with epilepsy (PWE) having had a recent seizure requiring OMM. Data on patient demographics, patient care plans, details of a recent seizure requiring emergency medication, and dose of OMM were collected from medical records. RESULTS: Study data from 146 PWE were included. The mean age of PWE was 41.0 years (SD 15.2) and mean weight was 64.8Kg (SD 18.2). Fifty-three percent of PWE were recorded as having intellectual disability. The most frequently used concomitant medications were lamotrigine (43%). The majority of seizures occurred at people's homes (n = 92, 63%). OMM was most often administered by family/professional care-givers (n = 75, 48.4%). Generalized (tonic/clonic) seizures were recorded in most people (n = 106, 72.6%). The most common initial dose of OMM was 10 mg (n = 124, 84.9%). The mean time to seizure cessation after administration of this initial dose was 5.5 minutes (SD = 4.5, Median 5.0, IQR 2.1-5.0). Only a minority of seizures led to ambulance callouts (n = 18, 12.3%) or hospital admissions (n = 13, 9%). CONCLUSION: This is the first observational study describing the use and effectiveness of OMM in adults in community settings. Minimal hospital admissions were reported in this cohort and the treatment was effective in ending seizures in adults in community settings

Physio4FMD: protocol for a multicentre randomised controlled trial of specialist physiotherapy for functional motor disorder

Background Patients with functional motor disorder (FMD) experience persistent and disabling neurological symptoms such as weakness, tremor, dystonia and disordered gait. Physiotherapy is usually considered an important part of treatment; however, sufficiently-powered controlled studies are lacking. Here we present the protocol of a randomised controlled trial (RCT) that aims to evaluate the clinical and cost effectiveness of a specialist physiotherapy programme for FMD. Methods/design The trial is a pragmatic, multicentre, single blind parallel arm randomised controlled trial (RCT). 264 Adults with a clinically definite diagnosis of FMD will be recruited from neurology clinics and randomised to receive either the trial intervention (a specialist physiotherapy protocol) or treatment as usual control (referral to a community physiotherapy service suitable for people with neurological symptoms). Participants will be followed up at 6 and 12 months. The primary outcome is the Physical Function domain of the Short Form 36 questionnaire at 12 months. Secondary domains of measurement will include participant perception of change, mobility, health-related quality of life, health service utilisation, anxiety and depression. Health economic analysis will evaluate the cost impact of trial and control interventions from a health and social care perspective as well as societal perspective. Discussion This trial will be the first adequately-powered RCT of physical-based rehabilitation for FMD. Trial registration International Standard Randomised Controlled Trials Number ISRCTN56136713. Registered 27 March 2018