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On the magnetospheric ULF wave counterpart of substorm onset
One nearāubiquitous 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) allāsky 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 groundā and spaceābased observations to be consistent, with average growth rates of ā¼0.01 sā1, lasting for ā¼4 min. Crossācorrelation suggests that the spaceābased observations lead those on the ground by approximately 1ā1.5 min. Meanwhile, spacecraft located premidnight and ā¼10 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
Pharmacist intervention in primary care to improve outcomes in patients with left ventricular systolic dysfunction
<b>Background</b> Meta-analysis of small trials suggests that pharmacist-led collaborative review and revision of medical treatment may improve outcomes in heart failure.<p></p>
<b>Methods and results</b> We studied patients with left ventricular systolic dysfunction in a cluster-randomized controlled, event driven, trial in primary care. We allocated 87 practices (1090 patients) to pharmacist intervention and 87 practices (1074 patients) to usual care. The intervention was delivered by non-specialist pharmacists working with family doctors to optimize medical treatment. The primary outcome was a composite of death or hospital admission for worsening heart failure. This trial is registered, number ISRCTN70118765. The median follow-up was 4.7 years. At baseline, 86% of patients in both groups were treated with an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. In patients not receiving one or other of these medications, or receiving less than the recommended dose, treatment was started, or the dose increased, in 33.1% of patients in the intervention group and in 18.5% of the usual care group [odds ratio (OR) 2.26, 95% CI 1.64ā3.10; P< 0.001]. At baseline, 62% of each group were treated with a Ī²-blocker and the proportions starting or having an increase in the dose were 17.9% in the intervention group and 11.1% in the usual care group (OR 1.76, 95% CI 1.31ā2.35; P< 0.001). The primary outcome occurred in 35.8% of patients in the intervention group and 35.4% in the usual care group (hazard ratio 0.97, 95% CI 0.83ā1.14; P = 0.72). There was no difference in any secondary outcome.<p></p>
<b>Conclusion</b> A low-intensity, pharmacist-led collaborative intervention in primary care resulted in modest improvements in prescribing of disease-modifying medications but did not improve clinical outcomes in a population that was relatively well treated at baseline
Isospin Splitting in the Baryon Octet and Decuplet
Baryon mass splittings are analyzed in terms of a simple model with general
pairwise interactions. At present, the masses are poorly known from
experiments. Improvement of these data would provide an opportunity to make a
significant test of our understanding of electromagnetic and quark-mass
contributions to hadronic masses. The problem of determining resonance masses
from scattering and production data is discussed.Comment: 9 pages, LATEX inc. 2 LATEX "pictures", CMU-HEP91-24-R9
Measured Sensitivity of the First Mark II Phased Array Feed on an ASKAP Antenna
This paper presents the measured sensitivity of CSIRO's first Mk. II phased
array feed (PAF) on an ASKAP antenna. The Mk. II achieves a minimum
system-temperature-over-efficiency of 78 K at 1.23 GHz
and is 95 K or better from 835 MHz to 1.8 GHz. This PAF was designed for the
Australian SKA Pathfinder telescope to demonstrate fast astronomical surveys
with a wide field of view for the Square Kilometre Array (SKA).Comment: 5 pages, 2 figures, accepted for publication in Electromagnetics in
Advanced applications (ICEAA), 2015 International Conference o
N-methyl-N-alkylpyrrolidinium nonafluoro-1-butanesulfonate salts : Ionic liquid properties and plastic crystal behaviour
A series of N-methyl-N-alkylpyrrolidinium nonafluoro-1-butanesulfonate salts were synthesised and characterised. The thermophysical characteristics of this family of salts have been investigated with respect to potential use as ionic liquids and solid electrolytes. N-Methyl-N-butylpyrrolidinium nonafluoro-1-butanesulfonate (p1,4NfO) has the lowest melting point of the family, at 94 °C. Electrochemical analysis of p1,4 NfO in the liquid state shows an electrochemical window of ~6 V. All compounds exhibit one or more solid–solid transitions at sub-ambient temperatures, indicating the existence of plastic crystal phases.<br /
The Functions of Groups: A Psychometric Analysis of the Group Resources Inventory
What do groups do for their members? A functional model that assumes groups satisfy a number of basic survival, psychological, informational, interpersonal, and collective needs is offered. The authors examined the comprehensiveness of the model by asking members of various types of naturally occurring groups to describe the benefits they gained through membership. Analysis of those descriptions identified 16 key interpersonal functions of groups (such as social comparison, social exchange, social control, social esteem, social identity, and social learning), and individuals\u27 evaluations of the quality of their group were systematically related to their ratings of the group\u27s functionality. The authors discuss possible applications of these findings for improving groups but have concluded that additional work is needed to determine the applicability of the functions model to psychotherapeutic groups
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