Mars riometer system

A riometer (relative ionospheric opacity meter) measures the intensity of cosmic radio noise at the surface of a planet. When an electromagnetic wave passes through the ionosphere collisions between charged particles (usually electrons) and neutral gases remove energy from the wave. By measuring the received signal intensity at the planet's surface and comparing it to the expected value (the quietday curve) a riometer can deduce the absorption (attenuation) of the trans-ionospheric signal. Thus the absorption measurements provide an indication of ionisation changes occurring in the ionosphere. To avoid the need for orbiting sounders riometers use the cosmic noise background as a signal source. Earth-based systems are not subject to the challenging power, volume and mass restriction that would apply to a riometer for Mars. Some Earth-based riometers utilise phased-array antennas in order to provide an imaging capability.UnpublishedVienna - Austria3.9. Fisica della magnetosfera, ionosfera e meteorologia spazialeope

Identification of clouds and aurorae in optical data images

In this paper we present an automatic image recognition technique used to identify clouds and aurorae in digital images, taken with a CCD all-sky imager. The image recognition algorithm uses image segmentation to generate a binary block object image. Object analysis is then performed on the binary block image, the results of which are used to assess whether clouds, aurorae and stars are present in the original image. The need for such an algorithm arises because the optical study of particle precipitation into the Earth's atmosphere by the Ionosphere and Radio Propagation Group at Lancaster generates vast data-sets, over 25 000 images/year, making manual classification of all the images impractical

Extension of SPIS to simulate dust electrostatic charging, transport and contamination of lunar probes

A modification of the Spacecraft Plasma Interaction Software has been undertaken under ESA contract 4000107327/12/NL/AK (SPIS-DUST). The primary goal is to provide mission designers with an engineering tool capable of predicting charged dust behavior in a given plasma environment involving a spacecraft / exploration unit in contact with complex topological features at various locations of the Moon’s surface. The tool also aims at facilitating dust contamination diagnostics for sensitive surfaces such as sensors optics, solar panels, thermal interfaces, etc. In this paper, the new user interface and the new numerical solvers developed in the frame of this project is presented. The pre-processing includes the building of a 3D lunar surface from a topology description (i.e. a point list), an interface to position the spacecraft and a merging interface for the spacecraft elements in contact with the lunar surface. Concerning the physical models, the new solvers have been developed in order to model the physics of the ejection of the dust from the soils, the dusts charging and transport in volume and the dust interaction and contamination of the spacecraft. The post-processing includes the standard outputs of SPIS for the electrostatic computation and the plasma plus dedicated instruments for the diagnosis of the dusts. A set of verification test cases are presented in order to demonstrate the new capabilities of this version of SPIS in realistic conditions

Assessing feasibility and acceptability of web-based enhanced relapse prevention for bipolar disorder (ERPonline): a randomized controlled trial

Background: Interventions that teach people with Bipolar Disorder (BD) to recognise and respond to early warning signs of relapse are NICE recommended but implementation in clinical practice is poor. Objective: This study tests the feasibility and acceptability of a randomised controlled trial to evaluate an online enhanced relapse prevention intervention (ERPonline), and reports preliminary evidence of effectiveness. Methods: Single blind, parallel primarily online randomised controlled trial (n=96) over 48 weeks comparing ERPonline plus usual treatment to waitlist (WL) control plus usual treatment for people with BD recruited through National Health Services, voluntary organisations, and media. Randomisation was independent, minimised on number of previous episodes (<8,8-20,21+). Primary outcomes were feasibility and acceptability assessed by rates of study recruitment and retention, levels of intervention use, adverse events and participant feedback. Process and clinical outcomes were assessed by telephone and online and compared using linear models with intention-to-treat analysis. Results: Two hundred and eighty people registered interest online, from which ninety-six met inclusion criteria, consented and were randomised (49 to WL, 47 to ERPonline) over seventeen months, with 80% retention in telephone and online follow up, except week 48 online (76%). Acceptability was high for both ERPonline and trial methods. ERPonline cost approximately £19,340 to create, and £2176 per year to host and maintain the site. Qualitative data highlighted the importance of the relationship users have with online interventions and how this is created as an extension of the relationship with the humans perceived as offering and supporting its use. Differences between the group means suggested that access to ERPonline was associated with: a more positive model of bipolar disorder at 24 (10.70 (0.90-20.5 95%CIs)) and 48 weeks (13.1 (2.44-23.93 95%CIs)); increased monitoring of early warning signs of depression at 48 weeks (-1.39 (-2.61, -.163 95%CIs)) and of (hypo)mania at 24 (-1.72 (-2.98, -0.47 95%CIs)) and 48 weeks (-1.61 (-2.92, -0.30 95%CIs)), compared to WL. There was no evidence of impact of ERPonline on clinical outcomes or medication adherence, but relapse rates across both arms were very low (15%) and the sample remained high functioning throughout. One person died by suicide prior to randomisation. Five people in ERPonline and six in WL control reported ideas of suicide or self-harm during the study. None were deemed study related by an independent Trial Steering Committee. Conclusions: ERPonline offers a cheap accessible option for people seeking ongoing support following successful treatment. However, given high functioning and low relapse rates in this study, testing clinical effectiveness for this population would require very large sample sizes. Building in human support to use ERPonline should be considere

New SPIS capabilities to simulate dust electrostatic charging, transport, and contamination of lunar probes

The spacecraft-plasma interaction simulator has been improved to allow for the simulation of lunar and asteroid dust emission, transport, deposition, and interaction with a spacecraft on or close to the lunar surface. The physics of dust charging and of the forces that they are subject to has been carefully implemented in the code. It is both a tool to address the risks faced by lunar probes on the surface and a tool to study the dust transport physics. We hereby present the details of the physics that has been implemented in the code as well as the interface improvements that allow for a user-friendly insertion of the lunar topology and of the lander in the simulation domain. A realistic case is presented that highlights the capabilities of the code as well as some general results about the interaction between a probe and a dusty environment

Simultaneous observation of auroral substorm onset in Polar satellite global images and ground-based all-sky images

Substorm onset has originally been defined as a longitudinally extended sudden auroral brightening (Akasofu initial brightening: AIB) followed a few minutes later by an auroral poleward expansion in ground-based all-sky images (ASIs). In contrast, such clearly marked two-stage development has not been evident in satellite-based global images (GIs). Instead, substorm onsets have been identified as localized sudden brightenings that expand immediately poleward. To resolve these differences, optical substorm onset signatures in GIs and ASIs are compared in this study for a substorm that occurred on December 7, 1999. For this substorm, the Polar satellite ultraviolet global imager was operated with a fixed filter (170 nm) mode, enabling a higher time resolution (37 s) than usual to resolve the possible two-stage development. These data were compared with 20-s-resolution green-line (557.7 nm) ASIs at Muonio in Finland. The ASIs revealed the AIB at 2124:50 UT and the subsequent poleward expansion at 2127:50 UT, whereas the GIs revealed only an onset brightening that started at 2127:49 UT. Thus, the onset in the GIs was delayed relative to the AIB and in fact agreed with the poleward expansion in the ASIs. The fact that the AIB was not evident in the GIs may be attributed to the limited spatial resolution of GIs for thin auroral arc brightenings. The implications of these results for the definition of substorm onset are discussed herein

A web-based, peer-supported self-management intervention to reduce distress in relatives of people with psychosis or bipolar disorder:the REACT RCT

BACKGROUND: Relatives caring for people with severe mental health problems find information and emotional support hard to access. Online support for self-management offers a potential solution. OBJECTIVE: The objective was to determine the clinical effectiveness and cost-effectiveness of an online supported self-management tool for relatives: the Relatives' Education And Coping Toolkit (REACT). DESIGN AND SETTING: This was a primarily online (UK), single-blind, randomised controlled trial, comparing REACT plus a resource directory and treatment as usual with the resource directory and treatment as usual only, by measuring user distress and other well-being measures at baseline and at 12 and 24 weeks. PARTICIPANTS: A total of 800 relatives of people with severe mental health problems across the UK took part; relatives who were aged ≥ 16 years, were experiencing high levels of distress, had access to the internet and were actively seeking help were recruited. INTERVENTION: REACT comprised 12 psychoeducation modules, peer support through a group forum, confidential messaging and a comprehensive resource directory of national support. Trained relatives moderated the forum and responded to messages. MAIN OUTCOME MEASURE: The main outcome was the level of participants' distress, as measured by the General Health Questionnaire-28 items. RESULTS: Various online and offline strategies, including social media, directed potential participants to the website. Participants were randomised to one of two arms: REACT plus the resource directory (n = 399) or the resource directory only (n = 401). Retention at 24 weeks was 75% (REACT arm, n = 292; resource directory-only arm, n = 307). The mean scores for the General Health Questionnaire-28 items reduced substantially across both arms over 24 weeks, from 40.2 (standard deviation 14.3) to 30.5 (standard deviation 15.6), with no significant difference between arms (mean difference -1.39, 95% confidence interval -3.60 to 0.83; p = 0.22). At 12 weeks, the General Health Questionnaire-28 items scores were lower in the REACT arm than in the resource directory-only arm (-2.08, 95% confidence interval -4.14 to -0.03; p = 0.027), but this finding is likely to be of limited clinical significance. Accounting for missing data, which were associated with higher distress in the REACT arm (0.33, 95% confidence interval -0.27 to 0.93; p = 0.279), in a longitudinal model, there was no significant difference between arms over 24 weeks (-0.56, 95% confidence interval -2.34 to 1.22; p = 0.51). REACT cost £142.95 per participant to design and deliver (£62.27 for delivery only), compared with £0.84 for the resource directory only. A health economic analysis of NHS, health and Personal Social Services outcomes found that REACT has higher costs (£286.77), slightly better General Health Questionnaire-28 items scores (incremental General Health Questionnaire-28 items score adjusted for baseline, age and gender: -1.152, 95% confidence interval -3.370 to 1.065) and slightly lower quality-adjusted life-year gains than the resource directory only; none of these differences was statistically significant. The median time spent online was 50.8 minutes (interquartile range 12.4-172.1 minutes) for REACT, with no significant association with outcome. Participants reported finding REACT a safe, confidential environment (96%) and reported feeling supported by the forum (89%) and the REACT supporters (86%). No serious adverse events were reported. LIMITATIONS: The sample comprised predominantly white British females, 25% of participants were lost to follow-up and dropout in the REACT arm was not random. CONCLUSIONS: An online self-management support toolkit with a moderated group forum is acceptable to relatives and, compared with face-to-face programmes, offers inexpensive, safe delivery of National Institute for Health and Care Excellence-recommended support to engage relatives as peers in care delivery. However, currently, REACT plus the resource directory is no more effective at reducing relatives' distress than the resource directory only. FUTURE WORK: Further research in improving the effectiveness of online carer support interventions is required. TRIAL REGISTRATION: Current Controlled Trials ISRCTN72019945. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 32. See the NIHR Journals Library website for further project information. Relatives of people with severe mental health problems need better access to information and emotional support. The Relatives’ Education And Coping Toolkit (REACT) is a website designed to do this. It includes lots of information presented in text and video, an online forum for relatives to share knowledge and experience, a messaging system where they can ask questions in confidence and a comprehensive directory of contact details for national organisations offering relevant support. Trained relatives support the forum and messaging. In the UK, we recruited 800 relatives of people with severe mental health problems: all were aged ≥ 16 years, had high levels of distress, had access to the internet and wanted help. We divided them into two equal groups: one group received REACT (including the resource directory), whereas the other group received the resource directory only. To ensure that there were no differences between groups at the start, relatives were allocated to the two groups randomly, so they had an equal chance of being in either group. We followed up with both groups at 12 and 24 weeks, and received data from approximately three-quarters of the participants. This trial found that REACT was acceptable, safe and inexpensive to deliver (£62.27 per relative), compared with face-to-face interventions, and that relatives using it felt well supported. However, once we accounted for missing data (relatives who dropped out of the trial or did not complete the follow-up questionnaires), there were no significant differences between the groups. There was no evidence that REACT increased relatives’ quality of life or saved money for the NHS

Reply to 'The dynamics of Van Allen belts revisited'

It is well-known that there are many wave-particle interaction processes which have the potential to affect the dynamics of the radiation belts [see e.g., the review by Mauk et al., 2013]. The issue that has continued to obstruct significant advances in our understanding of the radiation belts to the point of predictability is our ability to represent the nature of the magnetospheric processes controlling belt dynamics with sufficient accuracy to establish which dominate. In relation to the case examined here it is to determine which process or processes can act to create a third Van Allen radiation belt morphology in September 2012 as reported by Baker et al., (2013). As described in the main text of our Reply, and further expanded upon in the Supplementary Material presented here, we show that the original conclusion from Mann et al. (2016) remains valid. That is, a remnant belt and the third radiation belt morphology which arises following a subsequent flux recovery at higher L-shells, can be explained by the action of very fast outwards ULF wave radial diffusion associated with magnetopause shadowing. Contrary to the claims of the Comment by Shprits et al. (2017; hereafter S17), and the conclusions of modelling by Shprits et al. (2013; hereafter S13), the action of EMIC waves is not required

Explaining the dynamics of the ultra-relativistic third Van Allen radiation belt

Since the discovery of the Van Allen radiation belts over 50 years ago, an explanation for their complete dynamics has remained elusive. Especially challenging is understanding the recently discovered ultra-relativistic third electron radiation belt. Current theory asserts that loss in the heart of the outer belt, essential to the formation of the third belt, must be controlled by high-frequency plasma wave–particle scattering into the atmosphere, via whistler mode chorus, plasmaspheric hiss, or electromagnetic ion cyclotron waves. However, this has failed to accurately reproduce the third belt. Using a data driven, time-dependent specification of ultra-low-frequency (ULF) waves we show for the first time how the third radiation belt is established as a simple, elegant consequence of storm-time extremely fast outward ULF wave transport. High-frequency wave–particle scattering loss into the atmosphere is not needed in this case. When rapid ULF wave transport coupled to a dynamic boundary is accurately specified, the sensitive dynamics controlling the enigmatic ultra-relativistic third radiation belt are naturally explaine