229 research outputs found
The effect of men's body attitudes and motivation for gym attendance
The current study integrates men's body attitudes with implicitly and explicitly measured motivation to investigate the role of these factors in predicting gym attendance. Male participants (N = 99) who regularly attended a gym were recruited to participate in an online questionnaire. Participants completed implicit and explicit measures of motivation, explicitly-measured men's body attitudes, and reported the average number of gym visits per week. Attitudes related to body fat and explicitly-measured autonomous motivation significantly predicted typical gym attendance. Implicitly-measured motivation significantly and negatively predicted gym attendance. Results indicate some support for a dual-systems account of gym attendance. Men's body attitudes and autonomous motivation influences gym attendance; however, implicitly-measured motivation showed antagonistic effects. While individuals may explicitly state their autonomous motivation for gym attendance, attendance may be influenced at the explicit level. Health and fitness professionals may improve gym attendance by focusing on people's reasons for attending a gym, facilitating autonomous motivation in clients, and minimising the influence of controlled reasons for exercise
A behaviour sequence analysis of goal generation processes in a psychosis rehabilitation sample
Background:
It is suggested that goals are hierarchically organised, with goals at the highest level representing fundamental values and motivations. These abstract goals are said to have a series of sub-goals which represent a means of reaching higher-level goals. While a number of studies have explored goals in the context of psychosis, little is known about idiographic goal generation processes in those experiencing psychosis.
Methods:
Using a Behaviour Sequence Analysis approach, the aim of the current study was to assess the feasibility of the goal task for use with individuals experiencing psychosis. A total of 73 adults receiving care from UK rehabilitation services completed a goal task designed to elicit higher-level goals.
Results:
Results indicated that the goal task may be a feasible tool to support those experiencing psychosis to generate lower- and higher-level goals.
Conclusions:
The goal task utilised in the current study may therefore be a valuable goal generation tool for use by clinicians
Time- and vector-resolved magneto-optical Kerr effect measurements of large angle precessional reorientation in a 2×2 μ m2 ferromagnet
Copyright © 2009 American Institute of PhysicsThe precessional dynamics of a 2×2 μm2 CoFe/NiFe (4.6 nm) element stimulated by an in-plane pulsed magnetic field have been investigated using time- and vector-resolved Kerr microscopy measurements and micromagnetic simulations. The time-resolved signals were normalized to in-plane hysteresis loops obtained from the patterned material, and suggest that the magnetization reorients through an angle of 100°±10°. The simulations reveal that only the magnetization of the center region undergoes large angle reorientation, while the canted magnetization at the edges of the element remains pinned. An enhanced Gilbert damping parameter of 0.1 was required to reproduce the experimentally observed Kerr signals
Deep sequencing reveals the mitochondrial DNA variation landscapes of breast-to-brain metastasis blood samples
Use of microscale coplanar striplines with indium tin oxide windows in optical ferromagnetic resonance measurements
Copyright © 2005 American Institute of PhysicsIt is shown that a coplanar stripline structure containing indium tin oxide windows can be used to perform optical ferromagnetic resonance measurements on a sample grown on an opaque substrate, using a pulsed magnetic field of any desired orientation. The technique is demonstrated by applying it to a thin film of permalloy grown on a Si substrate. The measured precession frequency was found to be in good agreement with macrospin simulations. The phase of the oscillatory Kerr response was observed to vary as the probe spot was scanned across the coplanar stripline structure, confirming that the orientation of the pulsed field varied from parallel to perpendicular relative to the plane of the sample
Time resolved imaging of the non-linear bullet mode within an injection-locked nano-contact spin Hall nano-oscillator (article)
This is the author accepted manuscript. The final version is available from AIP Publishing via the DOI in this recordThe dataset associated with this article is located in ORE at: https://doi.org/10.24378/exe.923Injection of a radio frequency (RF) current was used to phase lock the SHNO to the TRSKM. The out of plane magnetization was detected by means of the polar magneto optical Kerr effect (MOKE). However, longitudinal MOKE images were dominated by an artifact arising from the edges of the Au NCs. Time resolved imaging revealed the simultaneous excitation of a non-linear `bullet' mode at the centre of the device, once the DC current exceeded a threshold value, and ferromagnetic resonance (FMR) induced by the RF current. However, the FMR response observed for sub-critical DC current values exhibits an amplitude minimum at the centre, which is attributed to spreading of the RF spin current due to the reactance of the device structure. This FMR response can be subtracted to yield images of the bullet mode. As the DC current is increased above threshold, the bullet mode appears to increase in size, suggesting increased translational motion. The reduced spatial overlap of the bullet and FMR modes, and this putative translational motion, may impede the injection locking and contribute to the reduced locking range observed within NC-SHNO devices. This illustrates a more general need to control the geometry of an injection-locked oscillator so that the autonomous dynamics of the oscillator exhibit strong spatial overlap with those resulting from the injected signal.We acknowledge the financial support from the Engineering and Physical Sciences Research Council (EPSRC) of the United Kingdom, via the EPSRC Centre for Doctoral Training in Metamaterials (Grant No. EP/L015331/1) and EPSRC Grants Nos. EP/I038470/1 and EP/P008550/1
Spatial mapping of torques within a spin hall nano-oscillator (article)
This is the final version. Available from American Physical Society via the DOI in this recordThe dataset associated with this article is located in ORE at: https://doi.org/10.24378/exe.1003Time-resolved scanning Kerr microscopy (TRSKM) was used to study precessional magnetization dynamics
induced by a radio frequency (RF) current within a Al2O3/Py(5 nm)/Pt(6 nm)/Au(150 nm) spin Hall nanooscillator
structure. The Au layer was formed into two needle-shaped electrical contacts that concentrated the
current in the center of a Py/Pt mesa of 4 μm diameter. Due to the spin Hall effect, current within the Pt
layer drives a spin current into the Py layer, exerting a spin transfer torque (STT). By injecting RF current
and exploiting the phase sensitivity of TRSKM and the symmetry of the device structure, the STT and Oersted
field torques have been separated and spatially mapped. The STT and torque due to the in-plane Oersted field are
observed to exhibit minima at the device center that is ascribed to spreading of RF current that is not observed for
DC current. Torques associated with the RF current may destabilize the position of the self-localized bullet mode
excited by the DC current and inhibit injection locking. The present study demonstrates the need to characterize
both DC and RF current distributions carefully.Engineering and Physical Sciences Research Council (EPSRC
Dynamic configurational anisotropy in nanomagnets
Copyright © 2007 The American Physical SocietyThe angular dependence of ultrafast magnetization dynamics in nanomagnets of square shape was studied by magneto-optical pump-probe measurements. In agreement with micromagnetic simulations, both the number of precessional modes and the values of their frequencies were observed to vary as the orientation of the external magnetic field was rotated in the element plane. We show that the observed behavior cannot be explained by the angular variation of the static effective magnetic field. Instead, it is found to originate from a new type of magnetic anisotropy-a dynamic configurational anisotropy, which is due to the variation of the dynamic effective magnetic field. Although always present, the dynamical anisotropy may dominate in nanoscale magnetic elements in which the static configurational anisotropy is suppressed
Imaging small-amplitude magnetization dynamics in a longitudinally magnetized microwire
Copyright © 2008 The American Physical SocietyWe have used time-resolved scanning Kerr microscopy to study spin waves in a magnetic microwire subjected to a bias magnetic field applied parallel to its long axis. The spin-wave spectra obtained from different points near one end of the wire reveal several normal modes. We found that modes of a higher frequency occupied regions located further from the end of the wire. This was interpreted in terms of the confinement of the spin-wave modes by a nonuniform demagnetizing field. Furthermore, at a particular distance from the end of the wire, two or more modes occupying different regions along the width of the wire were observed. This was interpreted in terms of the confinement of the spin-wave modes due to an asymmetric variation in the local angle between the static magnetization and the effective direction of the wave vector of the confined modes. Images of the dynamic magnetization that are acquired at fixed pump-probe time delays revealed stripes lying perpendicular to the long axis of the wire and, hence, to the applied magnetic field. We interpret the stripe pattern in terms of a collective mode of the quasiperiodic system of ripple domains existing within the polycrystalline sample. Cur results give an additional insight into the connection between the nonuniform static magnetic state in small magnetic elements and their precessional dynamics, which is fundamentally important for the design of future high-speed switching and spin-wave logic devices of magnonics
Driving under the influence of alcohol: a sequence analysis approach
Driving under the influence of alcohol: A sequence analysis approac
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