Cue-induced smoking urges deplete cigarette smokers' self-control resources

Background: Exposure to smoking-related cues leads to increased urge to smoke in regular cigarette smokers and resisting these urges requires considerable self-control. Purpose: Adopting a resource depletion model, two studies tested the hypothesis that resisting smoking urges depletes self-control resources. Methods: Adopting a within-participants randomized cross-over design, participants (study 1, N = 19; study 2, N = 32) were exposed to smoking-related (study 1: smoking images; study 2: cigarette cue-exposure task) and neutral (study 1: neutral images; study 2: drinking-straw task) cues with presentation order randomized. After each cue set, participants completed self-control tasks (study 1: handgrip task; study 2: handgrip and Stroop tasks), performance on which constituted dependent measures of self-control.Results: Self-control task performance was significantly impaired when exposed to smoking-related cues compared to neutral cues. No significant presentation-order effects, or interaction effects between stimulus and presentation order, were found. Conclusions: Findings corroborate our hypothesis that resisting smoking urges depletes cigarette smokers’ self-control resources and suggests that self-control capacity is governed by a limited resource

Next generation sequencing reveals widespread trypanosome diversity and polyparasitism in marsupials from Western Australia

In Western Australia a number of indigenous Trypanosoma spp. infect susceptible native marsupials, such as the woylie (Bettongia penicillata), brushtail possum (Trichosurus vulpecula), and chuditch (Dasyurus geoffroii). Two genotypes of Trypanosoma copemani (identified as G1 and G2) have been found in the woylie, and G2 has been implicated in the decline of this host species, making its presence of particular interest. Here we used targeted amplicon next generation sequencing (NGS) of the Trypanosoma 18S rDNA loci on 70 Trypanosoma-positive marsupial blood samples, to identify T. copemani genotypes and multiple Trypanosoma infections (polyparasitism) in woylies and cohabiting species in Western Australia. Polyparasitism with Trypanosoma spp. was found in 50% of the wildlife sampled, and within species diversity was high, with 85 zero-radius operational taxonomic units (ZOTUs) identified in nine putative parasite species. Trypanosoma copemani was assigned 17 ZOTUs and was identified in 80% of samples. The most abundant ZOTU isolated (63%) differed slightly from the published genotype of G1, and G2 was the second most abundant ZOTU (14%). Trypanosome diversity was significantly greater in woylies than in brushtail possums, and parasite community composition also differed significantly between these host species. One novel Trypanosoma spp. genotype (Trypanosoma sp. ANU2) was found in 20% of samples. A species of Crithidia was detected in a woylie, and two avian trypanosomes (Trypanosoma avium and Trypanosoma sp. AAT) were identified in woylies for the first time

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

Direct Detection of Pure ac Spin Current by X-Ray Pump-Probe Measurements.

PublishedThis is the author accepted manuscript. The final version is available from American Physical Society via the DOI in this record.There is another ORE record for this article: http://hdl.handle.net/10871/22513Despite recent progress in spin-current research, the detection of spin current has mostly remained indirect. By synchronizing a microwave waveform with synchrotron x-ray pulses, we use the ferromagnetic resonance of the Py (Ni_{81}Fe_{19}) layer in a Py/Cu/Cu_{75}Mn_{25}/Cu/Co multilayer to pump a pure ac spin current into the Cu_{75}Mn_{25} and Co layers, and then directly probe the spin current within the Cu_{75}Mn_{25} layer and the spin dynamics of the Co layer by x-ray magnetic circular dichroism. This element-resolved pump-probe measurement unambiguously identifies the ac spin current in the Cu_{75}Mn_{25} layer.We acknowledge helpful discussion with Arne Brataas. Financial support from the National Science Foundation Grant No. DMR-1504568, Future Materials Discovery Program through the National Research Foundation of Korea (Grant No. 2015M3D1A1070467), and Science Research Center Program through the National Research Foundation of Korea (Grant No. 2015R1A5A1009962) is gratefully acknowledged. The Advanced Light Source is supported by the U.S. Department of Energy under Award No. DE-AC02-05CH11231. J. D. acknowledges fellowship support from the China Scholarship Council and National Science Foundation of China under Grant No. 51331006. L. R. S., P. S. K., and R. J. H. acknowledge the support of the Engineering and Physical Sciences Research Council (EPSRC) through Grants No. EP/J018767/1 and No. EP/ I038470/1. G. v. d. L. acknowledges support of the EPSRC through Grant No. EP/J018767/1

Domain-wall pinning, nonadiabatic spin-transfer torque, and spin-current polarization in permalloy wires doped with vanadium

Copyright © 2010 The American Physical SocietyUsing pulsed-current measurements we investigate the domain-wall depinning via spin-transfer torque from pinning potentials in V-doped Ni80Fe20 wires. The domain-wall depinning boundary, showing the variation of threshold current density with longitudinal magnetic field is measured and reproduced using micromagnetic simulations. This method allows us to determine the spin-current polarization and nonadiabaticity parameter in these materials. By increasing the V concentration we show that the nonadiabaticity parameter is increased while the Gilbert damping is unaffected. On the other hand the spin-current polarization is decreased, resulting in larger threshold current densities

Implicit versus explicit attitude to doping: which better predicts athletes’ vigilance towards unintentional doping?

Objectives: This preliminary study examined whether implicit doping attitude, explicit doping attitude, or both, predicted athletes’ vigilance towards unintentional doping. Design: A cross-sectional correlational design. Methods: Australian athletes (N = 143; Mage = 18.13, SD = 4.63) completed measures of implicit doping attitude (brief single-category implicit association test), explicit doping attitude (Performance Enhancement Attitude Scale), avoidance of unintentional doping (Self-Reported Treatment Adherence Scale), and behavioural vigilance task of unintentional doping (reading the ingredients of an unfamiliar food product). Results: Positive implicit doping attitude and explicit doping attitude were negatively related to athletes’ likelihood of reading the ingredients table of an unfamiliar food product, and positively related to athletes’ vigilance toward unintentional doping. Neither attitude measures predicted avoidance of unintentional doping. Overall, the magnitude of associations by implicit doping attitude appeared to be stronger than that of explicit doping attitude. Conclusions: Athletes with positive implicit and explicit doping attitudes were less likely to read the ingredients table of an unknown food product, but were more likely to be aware of the possible presence of banned substances in a certain food product. Implicit doping attitude appeared to explain athletes’ behavioural response to the avoidance of unintentional doping beyond variance explained by explicit doping attitude

Publisher Correction: Graphene overcoats for ultra-high storage density magnetic media.

Publisher Correction: Graphene overcoats for ultra-high storage density magnetic media

Analysis of the Collective Behavior of a 10 by 10 Array of Fe3O4 Dots in a Large Micromagnetic Simulation

We report a full (3D) micromagnetic simulation of a set of 100 ferrite (Fe$_3$O$_4$) cylindrical dots, arranged in a 10 by 10 square (planar) array of side 3.27 $\mu$m, excited by an external in-plane magnetic field. The resulting power spectrum of magnetic excitations and the dynamical magnetization field at the resulting resonance modes were investigated. The absorption spectrum deviates considerably from that of a single particle reference simulation, presenting a mode-shifting and splitting effect. We found an inversion symmetry through the center of the array, in the sense that each particle and its inversion counterpart share approximately the same magnetization mode behavior. Magnonic designs aiming at synchronous or coherent tunings of spin-wave excitations at given spatially separated points within a regular square array may benefit from the new effects here described.Comment: 22 pages, 4 figures; accepted for publication in Physica E: Low-Dimensional Systems and Nanostructure

Graphene overcoats for ultra-high storage density magnetic media

Hard disk drives (HDDs) are used as secondary storage in digital electronic devices owing to low cost and large data storage capacity. Due to the exponentially increasing amount of data, there is a need to increase areal storage densities beyond~1Tb/in^2. This requires the thickness of carbon overcoats (COCs) to be<2 nm. However, friction, wear, corrosion, and thermal stability are critical concerns below 2 nm, limiting current technology, and restricting COC integration with heat assisted magnetic recording technology (HAMR). Here we show that graphene-based overcoats can overcome all these limitations, and achieve two-fold reduction in friction and provide better corrosion and wear resistance than state-of-the-art COCs, while withstanding HAMR conditions. Thus, we expect that graphene overcoats may enable the development of 4-10 Tb/in^2 areal density HDDs when employing suitable recording technologies, such as HAMR and HAMR+bit patterned media