1,476 research outputs found

    An AC electric trap for ground-state molecules

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    We here report on the realization of an electrodynamic trap, capable of trapping neutral atoms and molecules in both low-field and high-field seeking states. Confinement in three dimensions is achieved by switching between two electric field configurations that have a saddle-point at the center of the trap, i.e., by alternating a focusing and a defocusing force in each direction. AC trapping of 15ND3 molecules is experimentally demonstrated, and the stability of the trap is studied as a function of the switching frequency. A 1 mK sample of 15ND3 molecules in the high-field seeking component of the |J,K>=|1,1> level, the ground-state of para-ammonia, is trapped in a volume of about 1 mm^3

    Dissociable Processes of Cognitive Control during Error and Non-Error Conflicts: A Study of the Stop Signal Task

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    Conflict detection and subsequent behavioral adjustment are critical to daily life, and how this process is controlled has been increasingly of interest. A medial cortical region which includes the anterior cingulate cortex (ACC) has been theorized to act as a conflict detector that can direct prefrontal activity for behavioral adjustments. This conflict monitoring hypothesis was supported by many imaging studies of the Stroop task, with a focus on non-error processes. Here we sought to examine whether this circuit could be generalized to the stop signal task (SST), another behavioral paradigm widely used to study cognitive control. In particular, with a procedure to elicit errors in the SST, we examined whether error and non-error control were mediated by the same pathways.In functional magnetic resonance imaging of 60 healthy adults, we demonstrated that the medial cortical activity during stop success (SS) as compared to go success (G) trials is correlated with increased prefrontal activity in post-stop SS as compared to post-go SS trials, though this correlation was not specific to the medial cortical region. Furthermore, thalamic and insular rather than medial cortical activation during stop error (SE) as compared to G trials correlated with increased prefrontal activity in post-stop SS as compared to post-go SS trials.Taken together, these new findings challenge a specific role of the ACC and support distinct pathways for error and non-error conflict processing in cognitive control

    Young people today: news media, policy and youth justice

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    The new sociology of childhood sees children as competent social agents with important contributions to make. And yet the phase of childhood is fraught with tensions and contradictions. Public policies are required, not only to protect children, but also to control them and regulate their behaviour. For children and young people in the UK, youth justice has become increasingly punitive. At the same time, social policies have focused more on children's inclusion and participation. In this interplay of conflict and contradictions, the role the media play is critical in contributing to the moral panic about childhood and youth. In this article, we consider media representations of “antisocial” children and young people and how this belies a moral response to the nature of contemporary childhood. We conclude by considering how a rights-based approach might help redress the moralised politics of childhood representations in the media

    Studies on Soil Transmitted Helminthic Infection Among Coal Miners in Sawah Lunto, West Sumatra

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    Prevalensi cacing Perut diantara karyawan tambang batu bara Ombilin Sawah Lunto adalah 91,2 persen, 39,8 persen dan 13,persen masing-masing untuk cacing tambang, Ascaris lumbricoides dan Trichuris trichiura. Sebagian besar karyawan tambang bati bara ini menderita anemia (hanya 13,3 persen diantara mereka yang mempunyai kadar haemoglobin dalam batas-batas normal). Ukuran persen diantara mereka yang mempunyai kadar haemoglobin dalam batas-batas normal). Ukuran Unthropometrik menunjukkan bahwa hanya 62,5 persen berat badak untuk tinggi badan karyawan tambang ini termasuk kategori 90 persen atau lebih Standard nasional yang diusulkan. Percobaan pengobatan dengan menggunakan tetramisole (ascaridil) menunjukkan bahwa obat ini memberikan hasil yang memuaskan hanya untuk infestasi A. lumbricoides

    Discovery of a New Pulsar Wind Nebula in the Large Magellanic Cloud

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    We present new high-resolution radio and X-ray observations of the supernova remnant (SNR) B0453-685 in the Large Magellanic Cloud, carried out with the Australia Telescope Compact Array and the Chandra X-ray Observatory respectively. Embedded in the SNR shell is a compact central nebula producing both flat-spectrum polarized radio emission and non-thermal X-rays; we identify this source as a pulsar wind nebula (PWN) powered by an unseen central neutron star. We present a new approach by which the properties of a SNR and PWN can be used to infer upper limits on the initial spin period and surface magnetic field of the unseen pulsar, and conclude that this star was an initial rapid rotator with current properties similar to those of the Vela pulsar. As is the case for other similarly-aged sources, there is currently an interaction taking place between the PWN and the SNR's reverse shock.Comment: 4 pages of text plus 2 embedded EPS figures. Minor changes following referee's report. ApJ Letters, in pres
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