1,773 research outputs found
Plasma composition in a sigmoidal anemone active region
Using spectra obtained by the EIS instrument onboard Hinode, we present a
detailed spatially resolved abundance map of an active region (AR)-coronal hole
(CH) complex that covers an area of 359 arcsec x 485 arcsec. The abundance map
provides first ionization potential (FIP) bias levels in various coronal
structures within the large EIS field of view. Overall, FIP bias in the small,
relatively young AR is 2-3. This modest FIP bias is a consequence of the AR
age, its weak heating, and its partial reconnection with the surrounding CH.
Plasma with a coronal composition is concentrated at AR loop footpoints, close
to where fractionation is believed to take place in the chromosphere. In the
AR, we found a moderate positive correlation of FIP bias with nonthermal
velocity and magnetic flux density, both of which are also strongest at the AR
loop footpoints. Pathways of slightly enhanced FIP bias are traced along some
of the loops connecting opposite polarities within the AR. We interpret the
traces of enhanced FIP bias along these loops to be the beginning of
fractionated plasma mixing in the loops. Low FIP bias in a sigmoidal channel
above the AR's main polarity inversion line where ongoing flux cancellation is
taking place, provides new evidence of a bald patch magnetic topology of a
sigmoid/flux rope configfiuration.Comment: For on-line animation, see
http://www.mssl.ucl.ac.uk/~db2/fip_intensity.gif. Accepted by Ap
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mHealth: providing a mindfulness app for women with chronic pelvic pain in gynaecology outpatient clinics: qualitative data analysis of user experience and lessons learnt
OBJECTIVES: To determine whether a pre-existing smartphone app to teach mindfulness meditation is acceptable to women with chronic pelvic pain (CPP) and can be integrated into clinical practice within the National Health Service (NHS) CPP pathways, and to inform the design of a potential randomised clinical trial.
DESIGN: A prestudy patient and public involvement (PPI) group to collect feedback on the acceptability of the existing app and study design was followed by a three-arm randomised feasibility trial. In addition, we undertook interviews and focus groups with patients and staff to explore app usability and acceptability. We also obtained participant comments on the research process, such as acceptability of the study questionnaires.
SETTING: Two gynaecology clinics within Barts Health NHS, London, UK.
PARTICIPANTS: Patients with CPP lasting ≥6 months with access to smartphone or personal computer and understanding of basic English.
INTERVENTION: The intervention was mindfulness meditation content plus additional pain module delivered by a smartphone app. Active controls received muscle relaxation content from the same app. Passive (waiting list) controls received usual care.
MAIN OUTCOME MEASURES: Themes on user feedback, app usability and integration, and reasons for using/not using the app.
RESULTS: The use of the app was low in both active groups. Patients in the prestudy PPI group, all volunteers, were enthusiastic about the app (convenience, content, portability, flexibility, ease of use). Women contributing to the interview or focus group data (n=14), from a 'real world' clinic (some not regular app users), were less positive, citing as barriers lack of opportunities/motivation to use the app and lack of familiarity and capabilities with technology. Staff (n=7) were concerned about the potential need for extra support for them and for the patients, and considered the app needed organisational backing and peer acceptance.
CONCLUSION: The opinions of prestudy PPI volunteers meeting in their private time may not represent those of patients recruited at a routine clinic appointment. It may be more successful to codesign/codevelop an app with typical users than to adapt existing apps for use in real-world clinical populations.
TRIAL REGISTRATION NUMBER: ISRCTN10925965
Understanding recruitment and retention in the NHS community pharmacy stop smoking service: perceptions of smoking cessation advisers
NIHR Programme Grants for Applied Research Programme
(RP-PG-0609-10181
Expansion of magnetic clouds in the outer heliosphere
A large amount of magnetized plasma is frequently ejected from the Sun as
coronal mass ejections (CMEs). Some of these ejections are detected in the
solar wind as magnetic clouds (MCs) that have flux rope signatures. Magnetic
clouds are structures that typically expand in the inner heliosphere. We derive
the expansion properties of MCs in the outer heliosphere from one to five
astronomical units to compare them with those in the inner heliosphere. We
analyze MCs observed by the Ulysses spacecraft using insitu magnetic field and
plasma measurements. The MC boundaries are defined in the MC frame after
defining the MC axis with a minimum variance method applied only to the flux
rope structure. As in the inner heliosphere, a large fraction of the velocity
profile within MCs is close to a linear function of time. This is indicative
of} a self-similar expansion and a MC size that locally follows a power-law of
the solar distance with an exponent called zeta. We derive the value of zeta
from the insitu velocity data. We analyze separately the non-perturbed MCs
(cases showing a linear velocity profile almost for the full event), and
perturbed MCs (cases showing a strongly distorted velocity profile). We find
that non-perturbed MCs expand with a similar non-dimensional expansion rate
(zeta=1.05+-0.34), i.e. slightly faster than at the solar distance and in the
inner heliosphere (zeta=0.91+-0.23). The subset of perturbed MCs expands, as in
the inner heliosphere, at a significantly lower rate and with a larger
dispersion (zeta=0.28+-0.52) as expected from the temporal evolution found in
numerical simulations. This local measure of the expansion also agrees with the
distribution with distance of MC size,mean magnetic field, and plasma
parameters. The MCs interacting with a strong field region, e.g. another MC,
have the most variable expansion rate (ranging from compression to
over-expansion)
Monolithically integrated heterodyne optical phase-lock loop with RF XOR phase detector
We present results for an heterodyne optical phase-lock loop (OPLL), monolithically integrated on InP with external phase detector and loop filter, which phase locks the integrated laser to an external source, for offset frequencies tuneable between 0.6 GHz and 6.1 GHz. The integrated semiconductor laser emits at 1553 nm with 1.1 MHz linewidth, while the external laser has a linewidth less than 150 kHz. To achieve high quality phase locking with lasers of these linewidths, the loop delay has been made less than 1.8 ns. Monolithic integration reduces the optical path delay between the laser and photodiode to less than 20 ps. The electronic part of the OPLL was implemented using a custom-designed feedback circuit with a propagation delay of similar to 1 ns and an open-loop bandwidth greater than 1 GHz. The heterodyne signal between the locked slave laser and master laser has phase noise below. 90 dBc/Hz for frequency offsets greater than 20 kHz and a phase error variance in 10 GHz bandwidth of 0.04 rad(2). (C) 2011 Optical Society of Americ
Stellar Iron Abundances at the Galactic Center
We present measurements of [Fe/H] for six M supergiant stars and three giant
stars within 0.5 pc of the Galactic Center (GC) and one M supergiant star
within 30 pc of the GC. The results are based on high-resolution (lambda /
Delta lambda =40,000) K-band spectra, taken with CSHELL at the NASA Infrared
Telescope Facility.We determine the iron abundance by detailed abundance
analysis,performed with the spectral synthesis program MOOG.The mean [Fe/H] of
the GC stars is determined to be near solar,[Fe/H] = +0.12 0.22. Our
analysis is a differential analysis, as we have observed and applied the same
analysis technique to eleven cool, luminous stars in the solar neighborhood
with similar temperatures and luminosities as the GC stars. The mean [Fe/H] of
the solar neighborhood comparison stars, [Fe/H] = +0.03 0.16, is similar
to that of the GC stars. The width of the GC [Fe/H] distribution is found to be
narrower than the width of the [Fe/H] distribution of Baade's Window in the
bulge but consistent with the width of the [Fe/H] distribution of giant and
supergiant stars in the solar neighborhood.Comment: 41 pages, 9 figures, ApJ, in pres
Teaching Threshold Concepts in Virtual Reality: Exploring the Conceptual Requirements for Systems Design.
In a complex world students need to be equipping with a range of capabilities that will enable them to be critical and flexible learners and citizens. The central research objective in this paper is to explore the argument that virtual reality (VR) technologies, collaborative learning approaches and recognition of the values and importance of thresholds to learning are components that can equip students in and for the future. Threshold concepts are specific concepts which are identified as essential in the acquisition of thinking, learning and communication of understanding within a specific subject of learning. Threshold experiences occur when learners identify moments of “learning leaps” which are cognitive transformations or changes in conceptual role for the learner, enabling them to work at higher levels of abstraction and creativity. Virtual reality technology is increasingly applied in education and can be used to test multiple threshold concepts and applied to open problems that allow for low-stress and real-time interactions as well as supporting collaborative groups with rapid interactions. Applications built on VR can engage, immerse, and guide learners in ways not yet undertaken in the education of threshold concepts. Through literature review we explore the definitions of threshold concepts, VR technologies, and the opportunities for teaching threshold concepts using VR technologies. We additionally predict possible limitations of the technologies. Further, we propose a systems design approach as informed by our literature review
Educating professionals to support self-management in people with asthma or diabetes: protocol for a systematic review and scoping exercise
This report is independent research funded by the National Institute
for Health Research (Programme Development Grants, Implementing
supported asthma self-management in routine clinical care: designing,
refining, piloting and evaluating a whole systems implementation within an
MRC Phase IV programme of research, RP-DG-1213-10008). The views
expressed in this publication are those of the author(s) and not necessarily
those of the NHS, the National Institute for Health Research or the
Department of Health. This work is sponsored by the University of Edinburgh.
The funder and sponsor have not had any role in developing the protocol
Integrating Rocketbox Avatars with the Ubiq Social VR platform
Having a truly ethical, unbiased technology, requires people devel-oping and using this technology to have an equal opportunity to participate in its creation. In this sense, open-access tools are a way to share best practices and enhance collaboration. In this paper, we will present the integration of the Microsoft Rocketbox avatar library into the Unity networking library Ubiq. We will see how they may contribute to the research in the field of populated virtual environments
The Influence of Avatar Realism and Similarity in Shaping Group Dynamics in Collaborative Virtual Environments
Given the increasing use of social virtual reality applications, it is crucial to understand the impact of avatar design on social dynamics in populated virtual environments. This study investigates the impact of avatar realism and avatar similarity on dyadic relationships, with participants embodying either cartoony or realistic avatars. Participants interact with counterparts using the same or opposite avatar type, resulting in three conditions across pairs: realistic avatars group, cartoony avatars group, and mixed avatars group (one using a realistic avatar, the other a cartoony avatar). Through collaboration on puzzle tasks designed to foster interaction and cooperation, participants' experiences are assessed using a blend of questionnaires and behavioural metrics. The findings suggest that dyads perform better at collaborative tasks in the realistic avatars group condition, while the mixed avatars group outperforms the cartoony avatars group. These results provide valuable insights for optimizing avatar design and avatar similarity to enhance collaborative virtual environments
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