A flexible proton beam imaging energy spectrometer (PROBIES) for high repetition rate or single-shot high energy density (HED) experiments (invited).

The PROBIES diagnostic is a new, highly flexible, imaging and energy spectrometer designed for laser-accelerated protons. The diagnostic can detect low-mode spatial variations in the proton beam profile while resolving multiple energies on a single detector or more. When a radiochromic film stack is employed for "single-shot mode," the energy resolution of the stack can be greatly increased while reducing the need for large numbers of films; for example, a recently deployed version allowed for 180 unique energy measurements spanning ∼3 to 75 MeV with <0.4 MeV resolution using just 20 films vs 180 for a comparable traditional film and filter stack. When utilized with a scintillator, the diagnostic can be run in high-rep-rate (>Hz rate) mode to recover nine proton energy bins. We also demonstrate a deep learning-based method to analyze data from synthetic PROBIES images with greater than 95% accuracy on sub-millisecond timescales and retrained with experimental data to analyze real-world images on sub-millisecond time-scales with comparable accuracy.

Nonlinear wave evolution with data-driven breaking.

Wave breaking is the main mechanism that dissipates energy input into ocean waves by wind and transferred across the spectrum by nonlinearity. It determines the properties of a sea state and plays a crucial role in ocean-atmosphere interaction, ocean pollution, and rogue waves. Owing to its turbulent nature, wave breaking remains too computationally demanding to solve using direct numerical simulations except in simple, short-duration circumstances. To overcome this challenge, we present a blended machine learning framework in which a physics-based nonlinear evolution model for deep-water, non-breaking waves and a recurrent neural network are combined to predict the evolution of breaking waves. We use wave tank measurements rather than simulations to provide training data and use a long short-term memory neural network to apply a finite-domain correction to the evolution model. Our blended machine learning framework gives excellent predictions of breaking and its effects on wave evolution, including for external data.

Parents' experiences of participating in health-promoting activities at a family centre for preschool children in Sweden.

In Sweden, the family centre is a meeting place for families in a neighbourhood. It is a place for families to meet and exchange experiences and is a confidence-filled place for preschool children to play and develop. The staff at the family centre collaborate on early prevention strategies to promote health. Since 2014, the Public Dental Health Service in Södra Ryd, Skövde, has been a collaborative partner with the family centre. OBJECTIVES: To explore and describe the parents' experiences of participating in health-promoting activities at the family centre. BASIC RESEARCH DESIGN: A qualitative design based on interviews, analysed using a phenomenograpic approach. PARTICIPANTS: Six focus groups with two to six participants in each group. RESULTS: Three themes, all describing parents' experiences of visiting the family centre, emerged in the analysis. The themes were as follows; "Social fellowship", "A secure place" and "A learning environment". Each theme contained three categories, which represent the parents' different conceptions. CONCLUSIONS: The present study showed that the parents who visit the family centre found that the collaboration is perceived as positive and has many benefits. The participants found that the family centre is an institution that increases social interaction. Furthermore, meeting dental professionals in an arena outside the clinic creates confidence and makes people feel secure. Parents also learn both from the staff and from each other. According to these findings, the family centre is a suitable arena to work on health-promotion activities.

Experience of collaboration at a family centre for preschool children in Sweden.

In 2014, the Public Dental Health Service in Södra Ryd, Skövde, started a collaboration at the local family centre with the aim of performing health-promoting activities. Personnel at the family centre can play an important role in promoting children's health, including oral health, by testing preventive guidance. OBJECTIVES: To describe the personnel's experience of collaboration. BASIC RESEARCH DESIGN: Qualitative interviews with transcripts analysed using the phenomenographic approach. PARTICIPANTS: Seven staff with experience of collaboration. All were female, aged 34-62 and were dental nurses, child health-care nurses, preschool teacher or family centre co-ordinators. RESULTS: Three themes describing personnel's experience of collaboration at the family centre emerged: Collaboration produces an holistic approach, Co-location creates added value and Working methods result in development. Each theme was represented by three to four categories that represent different conceptions of collaboration at a family centre. CONCLUSIONS: The staff had found that the way of working was positive, mainly because it gave an increased overall view and that the co-location created added value. It also created development through mutual learning and new methods. However, it took time to establish collaboration and required permissive leadership.

The effect of bed roughness uncertainty on tidal stream power estimates for the Pentland Firth.

Uncertainty affects estimates of the power potential of tidal currents, resulting in large ranges in values reported for sites such as the Pentland Firth, UK. Kreitmair et al. (2019, R. Soc. open sci. 6, 180941. (doi:10.1098/rsos.191127)) have examined the effect of uncertainty in bottom friction on tidal power estimates by considering idealized theoretical models. The present paper considers the role of bottom friction uncertainty in a realistic numerical model of the Pentland Firth spanned by different fence configurations. We find that uncertainty in removable power estimates resulting from bed roughness uncertainty depends on the case considered, with relative uncertainty between 2% (for a fully spanned channel with small values of mean roughness and input uncertainty) and 44% (for an asymmetrically confined channel with high values of bed roughness and input uncertainty). Relative uncertainty in power estimates is generally smaller than (input) relative uncertainty in bottom friction by a factor of between 0.2 and 0.7, except for low turbine deployments and very high mean values of friction. This paper makes a start at quantifying uncertainty in tidal stream power estimates, and motivates further work for proper characterization of the resource, accounting for uncertainty inherent in resource modelling.

The effect of uncertain bottom friction on estimates of tidal current power.

Uncertainty affects estimates of the power potential of tidal currents, resulting in large ranges in values reported for a given site, such as the Pentland Firth, UK. We examine the role of bottom friction, one of the most important sources of uncertainty. We do so by using perturbation methods to find the leading-order effect of bottom friction uncertainty in theoretical models by Garrett & Cummins (2005 Proc. R. Soc. A 461, 2563-2572. (doi:10.1098/rspa.2005.1494); 2013 J. Fluid Mech. 714, 634-643. (doi:10.1017/jfm.2012.515)) and Vennell (2010 J. Fluid Mech. 671, 587-604. (doi:10.1017/S0022112010006191)), which consider quasi-steady flow in a channel completely spanned by tidal turbines, a similar channel but retaining the inertial term, and a circular turbine farm in laterally unconfined flow. We find that bottom friction uncertainty acts to increase estimates of expected power in a fully spanned channel, but generally has the reverse effect in laterally unconfined farms. The optimal number of turbines, accounting for bottom friction uncertainty, is lower for a fully spanned channel and higher in laterally unconfined farms. We estimate the typical magnitude of bottom friction uncertainty, which suggests that the effect on estimates of expected power lies in the range -5 to +30%, but is probably small for deep channels such as the Pentland Firth (5-10%). In such a channel, the uncertainty in power estimates due to bottom friction uncertainty remains considerable, and we estimate a relative standard deviation of 30%, increasing to 50% for small channels.

Stokes drift.

During its periodic motion, a particle floating at the free surface of a water wave experiences a net drift velocity in the direction of wave propagation, known as the Stokes drift (Stokes 1847 Trans. Camb. Philos. Soc.8, 441-455). More generally, the Stokes drift velocity is the difference between the average Lagrangian flow velocity of a fluid parcel and the average Eulerian flow velocity of the fluid. This paper reviews progress in fundamental and applied research on the induced mean flow associated with surface gravity waves since the first description of the Stokes drift, now 170 years ago. After briefly reviewing the fundamental physical processes, most of which have been established for decades, the review addresses progress in laboratory and field observations of the Stokes drift. Despite more than a century of experimental studies, laboratory studies of the mean circulation set up by waves in a laboratory flume remain somewhat contentious. In the field, rapid advances are expected due to increasingly small and cheap sensors and transmitters, making widespread use of small surface-following drifters possible. We also discuss remote sensing of the Stokes drift from high-frequency radar. Finally, the paper discusses the three main areas of application of the Stokes drift: in the coastal zone, in Eulerian models of the upper ocean layer and in the modelling of tracer transport, such as oil and plastic pollution. Future climate models will probably involve full coupling of ocean and atmosphere systems, in which the wave model provides consistent forcing on the ocean surface boundary layer. Together with the advent of new space-borne instruments that can measure surface Stokes drift, such models hold the promise of quantifying the impact of wave effects on the global atmosphere-ocean system and hopefully contribute to improved climate projections.This article is part of the theme issue 'Nonlinear water waves'.

Benchmark data from the literature for evaluation of new glucose sensing technologies.

New glucose sensors based on various technologies are being developed to provide information for improved therapy in diabetes. There is a need to establish rational performance standards for these sensors. Frequently sampled, direct blood glucose recordings representative of blood glucose excursions in diabetes are the "gold standard." An extensive literature search revealed a limited number of diabetic and nondiabetic blood glucose recordings suitable for this purpose. Certain blood glucose recordings reflect the diversity of glycemic dynamics and provide sufficient challenge for evaluation of sensor systems. These recordings were converted into an accessible electronic format. An example is given of the use of these benchmark data to estimate aliasing error, or the error due to insufficient sampling frequency, based on a hypothetical sensor system having some properties of conventional "fingerstick" systems. Discrete sampling systems accumulate substantial aliasing error as the sampling period increases.

Immobilized glucose oxidase in implantable glucose sensor technology.

Glucose oxidase has had a central role in previous glucose sensing methods and is key to the development of certain new glucose sensors. The immobilized enzyme is specific for glucose and sufficiently long-lived for many sensor applications, but new glucose sensing applications may place increased demands on the enzyme.

Is blood glucose predictable from previous values? A solicitation for data.

An important question about blood glucose control in diabetes is, Can present and future blood glucose values be predicted from recent blood glucose history? If this is possible, new continuous blood glucose monitoring technologies under development may lead to qualitatively better therapeutic capabilities. Not only could continuous monitoring technologies alert a user when a hypoglycemic episode or other blood glucose excursion is underway, but measurements may also provide sufficient information to predict near-future blood glucose values. A predictive capability based only on recent blood glucose history would be advantageous because there would be no need to involve models of glucose and insulin distribution, with their inherent requirement for detailed accounting of vascular glucose loads and insulin availability. Published data analyzed here indicate that blood glucose dynamics are not random, and that blood glucose values can be predicted, at least for the near future, from frequently sampled previous values. Data useful in further exploring this concept are limited, however, and an appeal is made for collection of more.

Telefacsimile from a user perspective.

A study conducted at Montana State University compared telefacsimile service with mail delivery. Recipients of telefax materials who answered questions about the purpose, timeliness, and quality of the materials were generally well pleased. Telefacsimile was found to be a cost-effective and efficient method of document delivery over long distances.