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Energy confinement comparable with tokamak quality is achieved in the Madison Symmetric Torus (MST) reversed field pinch (RFP) at a high beta and low toroidal magnetic field. Magnetic fluctuations normally present in the RFP are reduced via parallel current drive in the outer region of the plasma. In response, the electron temperature nearly triples and beta doubles. The confinement time increases tenfold (to ∼10 ms), which is comparable with Land H-mode scaling values for a tokamak with the same plasma current, density, heating power, size and shape. Runaway electron confinement is evidenced by a 100-fold increase in hard x-ray bremsstrahlung. Fokker-Planck modelling of the x-ray energy spectrum reveals that the high energy electron diffusion is independent of the parallel velocity, uncharacteristic of magnetic transport and more like that for electrostatic turbulence. The high core electron temperature correlates strongly with a broadband reduction of resonant modes at mid-radius where the stochasticity is normally most intense. To extend profile control and add auxiliary heating, rf current drive and neutral beam heating are in development. Low power lower-hybrid and electron Bernstein wave injection experiments are underway. Dc current sustainment via ac helicity injection (sinusoidal inductive loop voltages) is also being tested. Low power neutral beam injection shows that fast ions are well-confined, even in the presence of relatively large magnetic fluctuations.

Background Routinely recorded primary care data have been used for many years by sentinel networks for surveillance. More recently, real world data have been used for a wider range of research projects to support rapid, inexpensive clinical trials. Because the partial national lockdown in the United Kingdom due to the coronavirus disease (COVID-19) pandemic has resulted in decreasing community disease incidence, much larger numbers of general practices are needed to deliver effective COVID-19 surveillance and contribute to in-pandemic clinical trials. Objective The aim of this protocol is to describe the rapid design and development of the Oxford Royal College of General Practitioners Clinical Informatics Digital Hub (ORCHID) and its first two platforms. The Surveillance Platform will provide extended primary care surveillance, while the Trials Platform is a streamlined clinical trials platform that will be integrated into routine primary care practice. Methods We will apply the FAIR (Findable, Accessible, Interoperable, and Reusable) metadata principles to a new, integrated digital health hub that will extract routinely collected general practice electronic health data for use in clinical trials and provide enhanced communicable disease surveillance. The hub will be findable through membership in Health Data Research UK and European metadata repositories. Accessibility through an online application system will provide access to study-ready data sets or developed custom data sets. Interoperability will be facilitated by fixed linkage to other key sources such as Hospital Episodes Statistics and the Office of National Statistics using pseudonymized data. All semantic descriptors (ie, ontologies) and code used for analysis will be made available to accelerate analyses. We will also make data available using common data models, starting with the US Food and Drug Administration Sentinel and Observational Medical Outcomes Partnership approaches, to facilitate international studies. The Surveillance Platform will provide access to data for health protection and promotion work as authorized through agreements between Oxford, the Royal College of General Practitioners, and Public Health England. All studies using the Trials Platform will go through appropriate ethical and other regulatory approval processes. Results The hub will be a bottom-up, professionally led network that will provide benefits for member practices, our health service, and the population served. Data will only be used for SQUIRE (surveillance, quality improvement, research, and education) purposes. We have already received positive responses from practices, and the number of practices in the network has doubled to over 1150 since February 2020. COVID-19 surveillance has resulted in tripling of the number of virology sites to 293 (target 300), which has aided the collection of the largest ever weekly total of surveillance swabs in the United Kingdom as well as over 3000 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serology samples. Practices are recruiting to the PRINCIPLE (Platform Randomised trial of INterventions against COVID-19 In older PeopLE) trial, and these participants will be followed up through ORCHID. These initial outputs demonstrate the feasibility of ORCHID to provide an extended national digital health hub. Conclusions ORCHID will provide equitable and innovative use of big data through a professionally led national primary care network and the application of FAIR principles. The secure data hub will host routinely collected general practice data linked to other key health care repositories for clinical trials and support enhanced in situ surveillance without always requiring large volume data extracts. ORCHID will support rapid data extraction, analysis, and dissemination with the aim of improving future research and development in general practice to positively impact patient care. International Registered Report Identifier (IRRID) DERR1-10.2196/19773

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An ongoing study utilizes outcrop-scale seismic data and lithofacies data from cores and platform borings collected from the east Texas continental shelf to test assumptions and models that relate sedimentary facies patterns and sequence stratigraphy. The current data base consists of nearly 15 000 km of high-resolution seismic data and lithological data from hundreds of sediment cores and platform borings. The Texas shelf is ideally suited for this work because sediment supply during the Pleistocene was high enough to keep pace with the relatively rapid rise and fall in sea level, thus producing sequences that can be imaged on highresolution seismic records. Furthermore, sediment supply, shelf gradient, and the degree of diapirism and faulting vary across the shelf, so the relative roles of these agents in controlling the overall packaging of facies into systems tracts can be evaluated.Strong contrasts exist between low-sediment-supply (Trinity/Sabine) and high-sedimentsupply (Brazos and Colorado) fluvial systems and their associated systems tracts. The predominant difference is that sediment delivered to the shelf by the Trinity/Sabine fluvial system was, for the most part, deposited within the incised fluvial valleys. Only during lowstands did the Trinity/Sabine system deliver sediment directly to shelf-margin deltas and slope minibasins. Reincision, associated with fifth-order eustatic fluctuations, flushes the valley of sediments deposited during the previous transgression and highstand, thus large quantities of sediment are delivered from this valley system during lowstands. Transgressive shelf sand bodies occur adjacent to the Trinity and Sabine incised valleys and are scattered widely across the shelf. Backstepping parasequences, the product of the episodic nature of glacial eustatic sea-level rise, characterize the incised valley fill. The highstand systems tract is thin to absent in interfluve areas.The Brazos and Colorado rivers have much larger sediment supplies than the Trinity and Sabine rivers. They have filled their incised valleys with fluvial deposits and abandoned them to occupy several more shallow valleys. The result of this fluvial avulsion has been the sequestering of a significant part of the sediments delivered by these rivers to fluvial valleys on the shelf. Both the Colorado and Brazos rivers constructed large shelf-margin deltas during the lowstand, but these deltas differ in terms of their overall morphology and sediment facies. The ancient Colorado delta is sandy and it directly sourced two slope fans during the maximum lowstand. The Brazos shelf-margin delta consists mainly of mud and there is little evidence of significant bypass during the lowstand. During initial transgression, the Brazos/Colorado shelf-margin deltas backstepped onto the outer shelf. Rapid transgression and associated erosion removed the delta-plain beds. Continued transgression led to decapitation of sandy fluvial and deltaic facies, reworking the sands into widespread shelf sand bodies, and further backstepping...