357 research outputs found
British surfers and their attitudes and values toward the environment
The purpose of this study was to examine the attitudes of British surfers toward their environment. Eight surfers were interviewed and their views analyzed using an inductive thematic analysis to explore their perceptions of the factors that have influenced their engagement in proenvironmental behaviors. The findings suggest that surfers (in this sample), while motivated to engage in proenvironmental behaviors, are also influenced by a range of factors and appear to be primarily motivated by their identification and a need to maintain their experience of that sport. This reveals an inherent dilemma. Through their sport surfers are able to observe the effects of environmental degradation on the environment (e.g., polluted water), the ecosystem, and on their personal health. However, they are also aware of the trade-offs required in pursuing their sport that may damage the environment (e.g., toxic material involved in sport kit manufacture). When questioned, surfers stated they would be unwilling to give up their sport even at the cost of the environment in which those activities are experienced. This highlights a possibly common problem among environmentally minded outdoor enthusiasts: when do personal benefits outweigh the responsibilities of environmental stewardship? The value of these findings is discussed in relation to the promotion of proenvironmental behaviors and engagement with proenvironmental groups
Double and single recycled pulsars: an evolutionary puzzle?
We investigate the statistics of isolated recycled pulsars and double neutron
star binaries in the Galactic disk. Since recycled pulsars are believed to form
through accretion and spinup in close binaries, the isolated objects presumably
originate from disrupted progenitors of double neutron stars. There are a
comparable number of double neutron star systems compared to isolated recycled
pulsars. We find that standard evolutionary models cannot explain this fact,
predicting several times the number of isolated recycled pulsars than those in
double neutron star systems. We demonstrate, through population synthesis
calculations, that the velocity distribution of isolated recycled pulsars is
broader than for binary systems. When this is accounted for in a model for
radio pulsar survey selection effects, which include the effects of Doppler
smearing for the double neutron star binaries, we find that there is a small
(25%) bias towards the detection of double neutron star systems. This bias,
however, is not significant enough to explain the observational discrepancy if
standard (sigma = 265 km/s) neutron star natal kick velocities are invoked in
binary population syntheses. Population syntheses in which the 1D Maxwellian
velocity dispersion of the natal kick is sigma=170 km/s are consistent with the
observations. These conclusions further support earlier findings the neutron
stars formed in close interacting binaries receive significantly smaller natal
kicks than the velocities of Galactic single pulsars would seem to indicate.Comment: 12 pages, MNRAS (accepted
Radio Pulses along the Galactic Plane
We have surveyed 68 deg^2 along the Galactic Plane for single, dispersed
radio pulses. Each of 3027 independent pointings was observed for 68 s using
the Arecibo telescope at 430 MHz. Spectra were collected at intervals of 0.5 ms
and examined for pulses with duration 0.5 to 8 ms. Such single pulse analysis
is the most sensitive method of detecting highly scattered or highly dispersed
signals from pulsars with large pulse-to-pulse intensity variations. A total of
36 individual pulses from five previously known pulsars were detected, along
with a single pulse not associated with a previously known source. Follow-up
observations discovered a pulsar, PSR J1918+08, from which the pulse
originated. This pulsar has period 2.130 s and dispersion measure 30 pc cm^-3,
and has been seen to emit single pulses with strength up to 8 times the
average.Comment: 14 pages, 5 figures, AASTeX, accepted by the Astrophysical Journa
Experts react: Macron and Le Pen advance to the run-off in the French presidential election
France held the first round of its presidential election on 23 April, with Emmanuel Macron and Marine Le Pen making it to the second round. The centrist Macron is projected to have won 23.8 percent of the vote, while the Front National’s leader Le Pen came second with 21.5 percent. For the first time since the 1970s, no candidate from either mainstream party has made it through to the run-off, pointing at the possibility of a radical realignment in French politics. Keep an eye on this page for more expert reactions coming in throughout the day. Marta Lorimer: “Macron is expected to win the election, but it is still unclear whether he will be able to govern” Thomas Vitiello: “The recomposition of the French left has started” David Lees: “It would be unwise to write off Le Pen just yet” Andrew Glencross: “Neither candidate would have made it this far if it was not for the confluence of short-term and long-term crises in French society” Nick Parsons: “The blurring of ideological divisions may make the run-off vote closer than expected
Rethinking clinical trials of transcranial direct current stimulation: Participant and assessor blinding is inadequate at intensities of 2mA
Copyright @ 2012 The Authors. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and 85 reproduction in any medium, provided the original author and source are credited. The article was made available through the Brunel University Open Access Publishing Fund.Background: Many double-blind clinical trials of transcranial direct current stimulation (tDCS) use stimulus intensities of 2 mA despite the fact that blinding has not been formally validated under these conditions. The aim of this study was to test the assumption that sham 2 mA tDCS achieves effective blinding. Methods:
A randomised double blind crossover trial. 100 tDCS-naĂŻve healthy volunteers were incorrectly advised that they there were taking part in a trial of tDCS on word memory. Participants attended for two separate sessions. In each session, they completed a word memory task, then received active or sham tDCS (order randomised) at 2 mA stimulation intensity for 20 minutes and then repeated the word memory task. They then judged whether they believed they had received active stimulation and rated their confidence in that judgement. The blinded assessor noted when red marks were observed at the electrode sites post-stimulation. Results: tDCS at 2 mA was not effectively blinded. That is, participants correctly judged the stimulation condition greater than would be expected to by chance at both the first session (kappa level of agreement (Îş) 0.28, 95% confidence interval (CI) 0.09 to 0.47 p = 0.005) and the second session (Îş = 0.77, 95%CI 0.64 to 0.90), p = <0.001) indicating inadequate participant blinding. Redness at the reference electrode site was noticeable following active stimulation more than sham stimulation (session one, Îş = 0.512, 95%CI 0.363 to 0.66, p<0.001; session two, Îş = 0.677, 95%CI 0.534 to 0.82) indicating inadequate assessor blinding. Conclusions: Our results suggest that blinding in studies using tDCS at intensities of 2 mA is inadequate. Positive results from such studies should be interpreted with caution.GLM is supported by the National Health & Medical Research Council of Australia ID 571090
Profile instabilities of the millisecond pulsar PSR J1022+1001
We present evidence that the integrated profiles of some millisecond pulsars
exhibit severe changes that are inconsistent with the moding phenomenon as
known from slowly rotating pulsars. We study these profile instabilities in
particular for PSR J1022+1001 and show that they occur smoothly, exhibiting
longer time constants than those associated with moding. In addition, the
profile changes of this pulsar seem to be associated with a relatively
narrow-band variation of the pulse shape. Only parts of the integrated profile
participate in this process which suggests that the origin of this phenomenon
is intrinsic to the pulsar magnetosphere and unrelated to the interstellar
medium. A polarization study rules out profile changes due to geometrical
effects produced by any sort of precession. However, changes are observed in
the circularly polarized radiation component. In total we identify four
recycled pulsars which also exhibit instabilities in the total power or
polarization profiles due to an unknown phenomenon (PSRs J1022+1001,
J1730-2304, B1821-24, J2145-0750).
The consequences for high precision pulsar timing are discussed in view of
the standard assumption that the integrated profiles of millisecond pulsars are
stable. As a result we present a new method to determine pulse times-of-arrival
that involves an adjustment of relative component amplitudes of the template
profile. Applying this method to PSR J1022+1001, we obtain an improved timing
solution with a proper motion measurement of -17 \pm 2 mas/yr in ecliptic
longitude. Assuming a distance to the pulsar as inferred from the dispersion
measure this corresponds to an one-dimensional space velocity of 50 km/s.Comment: 29 pages, 12 figures, accepted for publication in Ap
Effect of types and anatomical arrangement of painful stimuli on conditioned pain modulation
Reduced pain perception during painful stimulation to another body region (ie, conditioned pain modulation [CPM]) is considered important for pain modulation and development of pain disorders. The various methods used to study CPM limit comparison of findings. We investigated the influence of key methodologic variations on CPM and the properties of CPM when the back is used for the test stimulus or the conditioning stimulus (CS). Two different test stimuli (pressure pain threshold and pain response to suprathreshold heat [Pain-45, ie, pain rated at 45 on a 0–100 numeric rating scale]) were assessed before and during application of a noxious or non-noxious (sham) CS. Eight blocks of trials varied the anatomic location (back and forearms) and arrangement (body side) of the stimuli. Pressure pain threshold (as the test stimulus) increased during application of noxious, but not non-noxious, CS when stimuli were applied to opposite body sides or heterotopic sites on one body side. Inconsistent with pain-induced CPM, Pain-45 decreased during both noxious and non-noxious CS. These findings indicate that 1) pressure pain threshold can be more confidently interpreted with respect to CPM evoked by a painful stimulus than Pain-45, 2) the back and forearm are equally effective as sites for stimuli, and 3) stimuli arrangement does not influence CPM, except for identical anatomic regions on the same body side
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