114 research outputs found
Older Adultsâ Uptake and Adherence to Exercise Classes: Instructorsâ Perspectives.
yesExercise classes provide a range of benefits for older adults, but adherence levels are poor. We know little of instructorsâ experiences of delivering exercise classes to older adults. Semi-structured interviews, informed by the Theory of Planned Behaviour (TPB), were conducted with instructors (n=19) delivering multi-component exercise classes to establish their perspectives on older adultsâ uptake and adherence to exercise classes. Analysis revealed âbarriersâ related to identity, choice/control, cost, venue and âsolutionsâ including providing choice, relating exercise to identity, a personal touch and social support. âBarriersâ to adherence included unrealistic expectations and social influences and âsolutionsâ identified were encouraging commitment, creating social cohesion and an emphasis on achieving outcomes. Older adultsâ attitudes were an underlying theme, which related to all barriers and solutions. The instructor plays an important, but not isolated, role in older adultsâ uptake and adherence to classes. Instructorsâ perspectives help us to further understand how we can design successful exercise classes
Dyson Pairs and Zero-Mass Black Holes
It has been argued by Dyson in the context of QED in flat spacetime that
perturbative expansions in powers of the electric charge e cannot be convergent
because if e is purely imaginary then the vacuum should be unstable to the
production of charged pairs. We investigate the spontaneous production of such
Dyson pairs in electrodynamics coupled to gravity. They are found to consist of
pairs of zero-rest mass black holes with regular horizons. The properties of
these zero rest mass black holes are discussed. We also consider ways in which
a dilaton may be included and the relevance of this to recent ideas in string
theory. We discuss accelerating solutions and find that, in certain
circumstances, the `no strut' condition may be satisfied giving a regular
solution describing a pair of zero rest mass black holes accelerating away from
one another. We also study wormhole and tachyonic solutions and how they affect
the stability of the vacuum.Comment: 41 pages LaTex, 5 figure
U(1) Gauge Field of the Kaluza-Klein Theory in the Presence of Branes
We investigate the zero mode dimensional reduction of the Kaluza-Klein
unifications in the presence of a single brane in the infinite extra dimension.
We treat the brane as fixed, not a dynamical object, and do not require the
orbifold symmetry. It seems that, contrary to the standard Kaluza-Klein models,
the 4D effective action is no longer invariant under the U(1) gauge
transformations due to the explicit breaking of isometries in the extra
dimension by the brane. Surprisingly, however, the linearized perturbation
analysis around the RS vacuum shows that the Kaluza-Klein gauge field does
possess the U(1) gauge symmetry at the linear level. In addition, the
graviscalar also behaves differently from the 4D point of view. Some physical
implications of our results are also discussed.Comment: 10 pages, revtex, no figure, version to appear in Phys. Rev. D,
possible caveats of our results due to the zero mode ansatz we used are
explained in more detai
Intensive disc-reverberation mapping of Fairall 9: First year of Swift and LCO monitoring
We present results of time-series analysis of the first year of the Fairall 9 intensive disc-reverberation campaign. We used Swift and the Las Cumbres Observatory global telescope network to continuously monitor Fairall 9 from X-rays to near-infrared at a daily to subdaily cadence. The cross-correlation function between bands provides evidence for a lag spectrum consistent with the Ï â λ4/3 scaling expected for an optically thick, geometrically thin blackbody accretion disc. Decomposing the flux into constant and variable components, the variable componentâs spectral energy distribution is slightly steeper than the standard accretion disc prediction. We find evidence at the Balmer edge in both the lag and flux spectra for an additional bound-free continuum contribution that may arise from reprocessing in the broad-line region. The inferred driving light curve suggests two distinct components, a rapidly variable (100 d) component with an opposite lag to the reverberation signal.JVHS and KH acknowledge support from the Science and Technology Facilities Council grant ST/R000824/1. RE gratefully acknowledges support from National Aeronautics and Space Administration (NASA) Swift Key Project
grant number 80NSSC19K0153. JMG gratefully acknowledges support from NASA under the ADAP award 80NSSC17K0126. AAB, KLP, and PAE acknowledge support from the UK Space Agency. Research by AJB was supported by National Science Foundation (NSF) grant AST-1907290. EMC gratefully acknowledges support from the NSF through grant AST-1909199. MV gratefully acknowledges
financial support from the Independent Research Fund Denmark via
grant number DFF 8021-00130. The authors appreciate the hard work and dedication of the Swift Observatory staff, who created a new UVOT mode in support of this project and put in considerableeffort in scheduling this large program. This work makes use of observations from the LCO network, and of the NASA/IPAC Infrared Science Archive, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. This research was made possible through the use of the AAVSO Photometric All-Sky Survey (APASS), funded by the Robert Martin Ayers Sciences Fund and
NSF AST-1412587. This research also made use of ASTROPY, a
community-developed core PYTHON package for astronomy (Astropy Collaboration et al. 2013), and MATPLOTLIB (Hunter 2007)
Dynamics of tree diversity in undisturbed and logged subtropical rainforest in Australia
In subtropical rainforest in eastern Australia, changes in the diversity of trees were compared under natural conditions and eight silvicultural regimes over 35 years. In the treated plots basal area remaining after logging ranged from 12 to 58 m2 per ha. In three control plots richness differed little over this period. In the eight treated plots richness per plot generally declined after intervention and then gradually increased to greater than original diversity. After logging there was a reduction in richness per plot and an increase in species richness per stem in all but the lightest selective treatments. The change in species diversity was related to the intensity of the logging, however the time taken for species richness to return to pre-logging levels was similar in all silvicultural treatments and was not effected by the intensity of treatment. These results suggest that light selective logging in these forests mainly affects dominant species. The return to high diversity after only a short time under all silvicultural regimes suggests that sustainability and the manipulation of species composition for desired management outcomes is possible
Womenâs beliefs about medicines and adherence to pharmacotherapy in pregnancy: Opportunities for community pharmacists?
Background During pregnancy women might weigh benefits of treatment against potential risks to the unborn child. However, non-adherence to necessary treatment can adversely affect both mother and child. To optimize pregnant womenâs beliefs and medication adherence, community pharmacists are ideally positioned to play an important role in primary care. Objective This narrative review aimed to summarize the evidence on 1) pregnant womenâs beliefs, 2) medication adherence in pregnancy, and 3) community pharmacistsâ counselling during pregnancy. Method Three search strategies were used in Medline and Embase to find original studies evaluating womenâs beliefs, medication adherence and community pharmacistsâ counselling during pregnancy. All original descriptive and analytic epidemiological studies performed in Europe, North America and Australia, written in English and published from 2000 onwards were included. Results We included 14 studies reporting on womenâs beliefs, 11 studies on medication adherence and 9 on community pharmacistsâ counselling during pregnancy. Women are more reluctant to use medicines during pregnancy and tend to overestimate the teratogenic risk of medicines. Risk perception varies with type of medicine, level of health literacy, education level and occupation. Furthermore, low medication adherence during pregnancy is common. Finally, limited evidence showed current community pharmacistsâ counselling is insufficient. Barriers hindering pharmacists are insufficient knowledge and limited access to reliable information. Conclusion Concerns about medication use and non-adherence are widespread among pregnant women. Community pharmacistsâ counselling during pregnancy is insufficient. Further education, training and research are required to support community pharmacists in fulfilling all the opportunities they have when counselling pregnant women
Achievements and Challenges in the Science of Space Weather
In June 2016 a group of 40 space weather scientists attended the workshop on Scientific Foundations of Space Weather at the International Space Science Institute in Bern. In this lead article to the volume based on the talks and discussions during the workshop we review some of main past achievements in the field and outline some of the challenges that the science of space weather is facing today and in the future.Peer reviewe
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Energetic particle influence on the Earth's atmosphere
This manuscript gives an up-to-date and comprehensive overview of the effects of energetic particle precipitation (EPP) onto the whole atmosphere, from the lower thermosphere/mesosphere through the stratosphere and troposphere, to the surface. The paper summarizes the different sources and energies of particles, principally
galactic cosmic rays (GCRs), solar energetic particles (SEPs) and energetic electron precipitation (EEP). All the proposed mechanisms by which EPP can affect the atmosphere
are discussed, including chemical changes in the upper atmosphere and lower thermosphere, chemistry-dynamics feedbacks, the global electric circuit and cloud formation. The role of energetic particles in Earthâs atmosphere is a multi-disciplinary problem that requires expertise from a range of scientific backgrounds. To assist with this synergy, summary tables are provided, which are intended to evaluate the level of current knowledge of the effects of energetic particles on processes in the entire atmosphere
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