“Anything that makes life’s journey better.” Exploring the use of digital technology by people living with motor neurone disease

Our aim was to explore the attitudes of those living with motor neuron disease towards digital technology. Postal and online questionnaires surveyed 83 people with MND (pwMND) and 54 friends and family members (fMND). Five pwMND and five fMND underwent semi-structured interviews. 82% of pwMND and 87% of fMND use technology every day with iPads and laptops being the devices most commonly used. pwMND used technology to help them continue to participate in everyday activities such as socialising, entertainment and accessing the internet. The internet provided peer support and information about MND but information could be distressing or unreliable. Participants preferred information from professionals and official organisations. Participants were generally supportive of using of technology to access medical care. Barriers to technology, such as lack of digital literacy skills and upper limb dysfunction, and potential solutions were identified. More challenging barriers included language and cognitive difficulties, and the fear of becoming dependent on technology. Addressing the barriers identified in this research could help pwMND access technology. However, as healthcare delivery becomes more reliant on digital technology, care should be taken to ensure that those who are unable or unwilling to use technology continue to have their needs met in alternative ways

Clinical aspects of motor neurone disease

© 2016. Motor neurone disease (MND) is a disabling and ultimately fatal disease of the motor system, with few effective treatments. Considerable heterogeneity is observed in the clinical motor features of MND, with extra-motor manifestations now also recognized as part of the condition. Diagnosis remains clinical, with appropriate investigations to exclude mimics. The multidisciplinary team approach is at the centre of holistic management of patients and families and can improve survival and quality of life. Although the disease remains incurable, survival benefit has been observed with the use of non-invasive ventilation and riluzole. Recent identification of genetic causes of MND, particularly the . C9orf72 hexanucleotide repeat expansion, adds to the expanding knowledge on aetiology and pathogenesis. However, the challenge of elucidating the underlying causes and establishing effective disease-modifying therapies continues through active research. We review MND, focusing on clinical features, diagnosis and management

A Bayesian analysis of regularised source inversions in gravitational lensing

Strong gravitational lens systems with extended sources are of special interest because they provide additional constraints on the models of the lens systems. To use a gravitational lens system for measuring the Hubble constant, one would need to determine the lens potential and the source intensity distribution simultaneously. A linear inversion method to reconstruct a pixellated source brightness distribution of a given lens potential model was introduced by Warren & Dye. In the inversion process, a regularisation on the source intensity is often needed to ensure a successful inversion with a faithful resulting source. In this paper, we use Bayesian analysis to determine the optimal regularisation constant (strength of regularisation) of a given form of regularisation and to objectively choose the optimal form of regularisation given a selection of regularisations. We consider and compare quantitatively three different forms of regularisation previously described in the literature for source inversions in gravitational lensing: zeroth-order, gradient and curvature. We use simulated data with the exact lens potential to demonstrate the method. We find that the preferred form of regularisation depends on the nature of the source distribution.Comment: 18 pages, 10 figures; Revisions based on referee's comments after initial submission to MNRA

Diagnosis of spinal xanthomatosis by next-generation sequencing: identifying a rare, treatable mimic of hereditary spastic paraparesis.

Cerebrotendinous xanthomatosis is an autosomal recessive disorder of bile acid metabolism causing a range of progressive neurological symptoms. Even in the presence of the classical triad of neurological dysfunction, tendon xanthoma and early onset cataracts, the diagnosis is often missed. It can mimic more common conditions such as hereditary spastic paraparesis or multiple sclerosis, particularly if the phenotype is spinal xanthomatosis where the disease causes a spastic paraplegia. Early recognition and treatment with chenodeoxycholic acid may prevent irreversible neurological damage. The introduction of next-generation sequencing to screen for a large number of genetic disorders associated with progressive spastic paraparesis will allow earlier identification and treatment of these patients and their families, and will particularly help in atypical cases such as the patient described here

Hexagonal dielectric resonators and microcrystal lasers

We study long-lived resonances (lowest-loss modes) in hexagonally shaped dielectric resonators in order to gain insight into the physics of a class of microcrystal lasers. Numerical results on resonance positions and lifetimes, near-field intensity patterns, far-field emission patterns, and effects of rounding of corners are presented. Most features are explained by a semiclassical approximation based on pseudointegrable ray dynamics and boundary waves. The semiclassical model is also relevant for other microlasers of polygonal geometry.Comment: 12 pages, 17 figures (3 with reduced quality

A pseudointegrable Andreev billiard

A circular Andreev billiard in a uniform magnetic field is studied. It is demonstrated that the classical dynamics is pseudointegrable in the same sense as for rational polygonal billiards. The relation to a specific polygon, the asymmetric barrier billiard, is discussed. Numerical evidence is presented indicating that the Poincare map is typically weak mixing on the invariant sets. This link between these different classes of dynamical systems throws some light on the proximity effect in chaotic Andreev billiards.Comment: 5 pages, 5 figures, to appear in PR

Evanescent wave approach to diffractive phenomena in convex billiards with corners

What we are going to call in this paper "diffractive phenomena" in billiards is far from being deeply understood. These are sorts of singularities that, for example, some kind of corners introduce in the energy eigenfunctions. In this paper we use the well-known scaling quantization procedure to study them. We show how the scaling method can be applied to convex billiards with corners, taking into account the strong diffraction at them and the techniques needed to solve their Helmholtz equation. As an example we study a classically pseudointegrable billiard, the truncated triangle. Then we focus our attention on the spectral behavior. A numerical study of the statistical properties of high-lying energy levels is carried out. It is found that all computed statistical quantities are roughly described by the so-called semi-Poisson statistics, but it is not clear whether the semi-Poisson statistics is the correct one in the semiclassical limit.Comment: 7 pages, 8 figure

Optimal Inverse Design of Magnetic Field Profiles in a Magnetically Shielded Cylinder

Magnetic shields that use both active and passive components to enable the generation of a tailored low-field environment are required for many applications in science, engineering, and medical imaging. Until now, accurate field nulling, or field generation, has only been possible over a small fraction of the overall volume of the shield. This is due to the interaction between the active field-generating components and the surrounding high-permeability passive shielding material. In this paper, we formulate the interaction between an arbitrary static current flow on a cylinder and an exterior closed high-permeability cylinder. We modify the Green’s function for the magnetic vector potential and match boundary conditions on the shield’s interior surface to calculate the total magnetic field generated by the system. We cast this formulation into an inverse optimization problem to design active–passive magnetic field shaping systems that accurately generate any physical static magnetic field in the interior of a closed cylindrical passive shield. We illustrate this method by designing hybrid systems that generate a range of magnetic field profiles to high accuracy over large interior volumes, and simulate them in real-world shields whose passive components have finite permeability, thickness, and axial entry holes. Our optimization procedure can be adapted to design active–passive magnetic field shaping systems that accurately generate any physical user-specified static magnetic field in the interior of a closed cylindrical shield of any length, enabling the development and miniaturization of systems that require accurate magnetic shielding and control

Spectral properties of quantized barrier billiards

The properties of energy levels in a family of classically pseudointegrable systems, the barrier billiards, are investigated. An extensive numerical study of nearest-neighbor spacing distributions, next-to-nearest spacing distributions, number variances, spectral form factors, and the level dynamics is carried out. For a special member of the billiard family, the form factor is calculated analytically for small arguments in the diagonal approximation. All results together are consistent with the so-called semi-Poisson statistics.Comment: 8 pages, 9 figure

Process evaluation and exploration of telehealth in motor neuron disease in a UK specialist centre

Objectives To evaluate the processes involved in using a novel digitally enabled healthcare system (telehealth in motor neuron disease (TiM)) in people living with motor neuron disease (MND) and their informal carers. We examined TiM implementation, potential mechanisms of impact and contextual factors that might influence TiM implementation or impact. Design An 18-month, single-centre process evaluation within a randomised, pilot and feasibility study. Intervention TiM plus usual care versus usual care alone. Setting A specialist UK MND care centre. Participants 40 patients with MND and 37 primary informal carers. Primary and secondary outcome measures Patient, carer and staff outcomes and experiences using semistructured interviews. Descriptive data on implementation and use of TiM. Results The TiM was acceptable and accessible to patients, carers and staff. Intervention uptake and adherence were good: 14 (70%) patients completed a TiM session at least fortnightly. Barriers to TiM use (such as technology experience and disability) were overcome with well-designed technology and face-to-face training. Reported potential benefits of TiM included improved communication and care coordination, reassurance, identification of complications and the potential for TiM to be an alternative or addition to clinic. Benefits depended on patients’ current level of needs or disability. The main challenges were the large number of alerts that were generated by TiM, how the clinicians responded to these alerts and the mismatch between patient/carer expectations and nurses actions. This could be improved by better communication systems and adjusting the alerts algorithm. Conclusion TiM has the potential to facilitate access to specialist care, but further iterative developments to the intervention and process evaluations of the TiM in different services are required