3,032 research outputs found
Interplanetary Coronal Mass Ejections observed by MESSENGER and Venus Express
Interplanetary coronal mass ejections (ICMEs) observed by the MESSENGER (MES)
and Venus Express (VEX) spacecraft have been catalogued and analysed. The ICMEs
were identified by a relatively smooth rotation of the magnetic field direction
consistent with a flux rope structure, coinciding with a relatively enhanced
magnetic field strength. A total of 35 ICMEs were found in the surveyed MES
data (primarily from March 2007 to April 2012), and 84 ICMEs in the surveyed
VEX data (from May 2006 to December 2013). The ICME flux rope configurations
have been determined. Ropes with northward leading edges were about four times
more common than ropes with southward leading edges, in agreement with a
previously established solar cycle dependence. Ropes with low inclinations to
the solar equatorial plane were about four times more common than ropes with
high inclinations, possibly an observational effect. Left and right-handed
ropes were observed in almost equal numbers. In addition, data from MES, VEX,
STEREO-A, STEREO-B and ACE were examined for multipoint signatures of the
catalogued ICMEs. For spacecraft separations below 15{\deg} in heliocentric
longitude, the second spacecraft observed the ICME flux rope in 82% of cases;
this percentage dropped to 49% for separations between 15 and 30{\deg}, to 18%
for separations between 30 and 45{\deg}, and to 12% for separations between 45
and 60{\deg}. As spacecraft separation increased, it became increasingly likely
that only the sheath and not the flux rope of the ICME was observed, in
agreement with the notion that ICME flux ropes are smaller in longitudinal
extent than the shocks or discontinuities that they often drive. Furthermore,
this study has identified 23 ICMEs observed by pairs of spacecraft close to
radial alignment. A detailed analysis of these events could lead to a better
understanding of how ICMEs evolve during propagation.Comment: 28 pages, 7 figure
Recommended from our members
On the magnetospheric ULF wave counterpart of substorm onset
One nearâubiquitous signature of substorms observed on the ground is the azimuthal structuring of the onset auroral arc in the minutes prior to onset. Termed auroral beads, these optical signatures correspond to concurrent exponential increases in ground ultralow frequency (ULF) wave power and are likely the result of a plasma instability in the magnetosphere. Here, we present a case study showing the development of auroral beads from a Time History of Events and Macroscale Interactions during Substorms (THEMIS) allâsky camera with near simultaneous exponential increases in auroral brightness, ionospheric and conjugate magnetotail ULF wave power, evidencing their intrinsic link. We further present a survey of magnetic field fluctuations in the magnetotail around substorm onset. We find remarkably similar superposed epoch analyses of ULF power around substorm onset from space and conjugate ionospheric observations. Examining periods of exponential wave growth, we find the groundâ and spaceâbased observations to be consistent, with average growth rates of âŒ0.01 sâ1, lasting for âŒ4 min. Crossâcorrelation suggests that the spaceâbased observations lead those on the ground by approximately 1â1.5 min. Meanwhile, spacecraft located premidnight and âŒ10 RE downtail are more likely to observe enhanced wave power. These combined observations lead us to conclude that there is a magnetospheric counterpart of auroral beads and exponentially increasing ground ULF wave power. This is likely the result of the linear phase of a magnetospheric instability, active in the magnetotail for several minutes prior to auroral breakup
A randomised controlled feasibility trial of the Graded Repetitive Arm Strengthening Programme delivered to survivors of stroke at home
BACKGROUND/AIMS:
This randomised controlled feasibility trial evaluated the recruitment, engagement and effect of the Graded Repetitive Arm Strengthening Programme in a community rehabilitation setting in London, UK.
METHODS: A parallel design was used to ascertain the effect of the Graded Repetitive Arm Strengthening Programme plus standard care compared to standard care only over four weeks. Eleven participants were randomised using permuted blocks randomisation following discharge, with six participants allocated to the Graded Repetitive Arm Strengthening Programme (study) group and five to the standard care (control) group. The primary outcome was the Wolf Motor Function Test. Secondary outcomes were the Motor Activity Log and grip strength.
RESULTS:
A total of five participants in each group were analysed as one person withdrew from the study group. Participants in the study group gave more time to supplementing their exercise time independently (160% more vs 42% more). Most Wolf Motor Function Test tasks' time and function data showed a small difference in favour of the Graded Repetitive Arm Strengthening Programme. Results were re-examined using a Bayesian structural equation model to quantify changes in the underlying impairment. This showed significant differences: 40% faster task completion (P<0.001, 95% confidence level [CI] 30â49%), mean improvement of 0.54 on the five-point functional ability score (P<0.001, 95% CI 0.39â0.68), odds ratio of 0.05 for non-completion of task (P<0.001, 95% CI 0.02â0.14).
CONCLUSIONS: This study has shown that implementing the Graded Repetitive Arm Strengthening Programme is feasible and may have a greater effect on outcomes when delivered as part of care in a community rehabilitation setting. The analysis of the Wolf Motor Function Test was also critiqued
Rules of Engagement: Journalistsâ attitudes to industry influence in health news reporting.
Health-related industries use a variety of methods to influence health news, including the formation and maintenance of direct relationships with journalists. These interactions have the potential to subvert news reporting such that it comes to serve the interests of industry in promoting their products, rather than the public interest in critical and accurate news and information. Here we report the findings of qualitative interviews conducted in Sydney, Australia, in which we examined journalistsâ experiences of, and attitudes towards, their relationships with health-related industries. Participantsâ belief in their ability to manage industry influence and their perceptions of what it means to be unduly influenced by industry raise important concerns relating to the psychology of influence and the realities of power relationships between industry and journalists. The analysis also indicates ways in which concerned academics and working journalists might establish more fruitful dialogue regarding the role of industry in health-related news and the extent to which increased regulation of journalist-industry relationships might be needed.NHMR
Power and control in interactions between journalists and health-related industries â the view from industry.
The mass media is a major source of health information for the public, and as such the quality and independence of health news reporting is an important concern. Concerns have been expressed that journalists reporting on health are increasingly dependent on their sources â including representatives of industries responsible for manufacturing health-related products â for story ideas and content. Many critics perceive an imbalance of power between journalists and industry sources, with industry being in a position of relative power, however the empirical evidence to support this view is limited. The analysis presented here â which is part of a larger study of industry-journalist relationships â draws on in-depth, semi-structured interviews with representatives of health-related industries in Australia to inductively examine their perceptions of power relations between industry and journalists. Participants painted a picture in which journalists, rather than themselves, were in a position to control the nature, extent, and outcome of their interactions with industry sources. Our results resonate with the concept of âmediatisationâ as it has been applied in the domain of political reporting. It appears that, from the perspective of industry representatives, the imposition of media logic on health-related industries may inappropriately influence the information that the public receives about health-related products.
KEYWORDS: journalism, ethics, power, public health, qualitative researchNHMR
Views of health journalists, industry employees and news consumers about disclosure and regulation of industry-journalist relationships: An empirical ethical study
Bioethicists and policymakers are increasingly concerned about the effects on health journalism of relationships between journalists and private corporations. The concern is that relationships between journalists and manufacturers of medicines, medical devices, complementary medicines, and food can and do distort health reporting. This is a problem because health news is known to have a major impact on the publicâs health-related expectations and behaviour. Commentators have proposed two related approaches to protecting the public from potential harms arising from industry-journalist interactions: greater transparency and external regulation. To date, few empirical studies have examined stakeholdersâ views of industry-journalist relationships and how these should be managed. We conducted interviews with 13 journalists and 12 industry employees, and two focus groups with consumers. Our findings, which are synthesised here, provide empirical support for the need for greater transparency and regulation of industry-journalist relationships. Our findings also highlight several likely barriers to instituting such measures, which will need to be overcome if transparency and regulation are to be accepted by stakeholder and have their intended effect on both the quality of journalism and the actions of news consumers.NHMR
Analytic structure of the S-matrix for singular quantum mechanics
The analytic structure of the S-matrix of singular quantum mechanics is examined within a multichannel framework, with primary focus on its dependence with respect to a parameter (Ω) that determines the boundary conditions. Specifically, a characterization is given in terms of salient mathematical and physical properties governing its behavior. These properties involve unitarity and associated current-conserving Wronskian relations, time-reversal invariance, and Blaschke factorization. The approach leads to an interpretation of effective nonunitary solutions in singular quantum mechanics and their determination from the unitary family.Fil: Camblong, Horacio E.. University of San Francisco; Estados UnidosFil: Epele, Luis Nicolas. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata. Instituto de FĂsica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de FĂsica La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de FĂsica. Laboratorio de FĂsica TeĂłrica; ArgentinaFil: Fanchiotti, Huner. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata. Instituto de FĂsica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de FĂsica La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de FĂsica. Laboratorio de FĂsica TeĂłrica; ArgentinaFil: GarcĂa Canal, Carlos Alberto. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata. Instituto de FĂsica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de FĂsica La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de FĂsica. Laboratorio de FĂsica TeĂłrica; Argentin
Strange Decays of Nonstrange Baryons
The strong decays of excited nonstrange baryons into the final states Lambda
K, Sigma K, and for the first time into Lambda(1405) K, Lambda(1520) K,
Sigma(1385) K, Lambda K*, and Sigma K*, are examined in a relativized quark
pair creation model. The wave functions and parameters of the model are fixed
by previous calculations of N pi and N pi pi, etc., decays. Our results show
that it should be possible to discover several new negative parity excited
baryons and confirm the discovery of several others by analyzing these final
states in kaon production experiments. We also establish clear predictions for
the relative strengths of certain states to decay to Lambda(1405) K and
Lambda(1520) K, which can be tested to determine if a three-quark model of the
Lambda(1405) K is valid. Our results compare favorably with the results of
partial wave analyses of the limited existing data for the Lambda K and Sigma K
channels. We do not find large Sigma K decay amplitudes for a substantial group
of predicted and weakly established negative-parity states, in contrast to the
only previous work to consider decays of these states into the strange final
states Lambda K and Sigma K.Comment: 25 pages, 8 figures, RevTe
Widening the debate about conflict of interest: addressing relationships between journalists and the pharmaceutical industry
The phone-hacking scandal that led to the closure of the News of the World newspaper in Britain has prompted international debate about media practices and regulation. It is timely to broaden the discussion about journalistic ethics and conduct to include consideration of the impact of media practices upon the populationâs health. Many commercial organizations cultivate relationships with journalists and news organizations with the aim of influencing the content of health-related news and information communicated through the media. Given the significant influence of the media on the health of individuals and populations, we should be alert to the potential impact of industry-journalist relationships on health care, health policy and public health. The approach taken by the medical profession to its interactions with the pharmaceutical industry provides a useful model for management of industry influence.
Keywords
Journalism, mass media, pharmaceutical industry, conflict of interest, ethics, media regulationNHMR
Health journalistsâ perceptions of their professional roles and responsibilities for ensuring the veracity of reports of health research
Health industries attempt to influence the public through the news media and through
their relationships with expert academics and opinion leaders. This paper reports the
results of a study of journalistsâ perceptions of their professional roles and
responsibilities with regard to relationships between industry and academia.
Journalists believed that responsibility for the validity of their reports rested with
academics and systems of peer review. However this fails to account for the extent
these interactions and the failures of peer review. Health journalistsâ retention of a
critical stance regarding industry-academia relationships will include advocacy for
and adoption of mandatory reporting of these relationships
- âŠ