413 research outputs found

    Experimental observation of high-order quantum accelerator modes.

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    Using a freely falling cloud of cold cesium atoms periodically kicked by pulses from a vertical standing wave of laser light, we present the first experimental observation of high-order quantum accelerator modes. This confirms the recent prediction by Fishman, Guarneri, and Rebuzzini [Phys. Rev. Lett.10.1103/PhysRevLett.89.084101 89, 084101 (2002)]. We also show how these accelerator modes can be identified with the stable regions of phase space in a classical-like chaotic system, despite their intrinsically quantum origin

    An updated measurement of the Hubble constant from near-infrared observations of Type Ia supernovae

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    We present a measurement of the Hubble constant (H0H_0) using type Ia supernova (SNe Ia) in the near-infrared (NIR) from the recently updated sample of SNe Ia in nearby galaxies with distances measured via Cepheid period-luminosity relations by the SHOES project. We collect public near-infrared photometry of up to 19 calibrator SNe Ia and further 57 SNe Ia in the Hubble flow (z>0.01z>0.01), and directly measure their peak magnitudes in the JJ and HH band by Gaussian processes and spline interpolation. Calibrator peak magnitudes together with Cepheid-based distances are used to estimate the average absolute magnitude in each band, while Hubble-flow SNe are used to constrain the zero-point intercept of the magnitude-redshift relation. Our baseline result of H0H_0 is 72.3±1.472.3\pm1.4 (stat) ±1.4\pm1.4 (syst) km s1^{-1} Mpc1^{-1} in the JJ band and 72.3±1.372.3\pm1.3 (stat) ±1.4\pm1.4 (syst) km s1^{-1} Mpc1^{-1} in the HH band, where the systematic uncertainties include the standard deviation of up to 21 variations of the analysis, the 0.7\% distance scale systematic from SHOES Cepheid anchors, a photometric zeropoint systematic, and a cosmic variance systematic. Our final measurement represents a measurement with a precision of 2.8\% in both bands. The variant with the largest change in H0H_0 is when limiting the sample to SNe from CSP and CfA programmes, noteworthy because these are the best calibrated, yielding H075H_0\sim75 km s1^{-1} Mpc1^{-1} in both bands. We demonstrate stretch and reddening corrections are still useful in the NIR to standardize SN Ia NIR peak magnitudes. Based on our results, in order to improve the precision of the H0H_0 measurement with SNe Ia in the NIR in the future, we would need to increase the number of calibrator SNe Ia, be able to extend the Hubble-Lema\^itre diagram to higher-z, and include standardization procedures to help reducing the NIR intrinsic scatter.Comment: 15 pages, 8 figures. Accepted in A&

    Mental Health of Parents and Life Satisfaction of Children: A Within-Family Analysis of Intergenerational Transmission of Well-Being

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    This paper addresses the extent to which there is an intergenerational transmission of mental health and subjective well-being within families. Specifically it asks whether parents’ own mental distress influences their child’s life satisfaction, and vice versa. Whilst the evidence on daily contagion of stress and strain between members of the same family is substantial, the evidence on the transmission between parental distress and children’s well-being over a longer period of time is sparse. We tested this idea by examining the within-family transmission of mental distress from parent to child’s life satisfaction, and vice versa, using rich longitudinal data on 1,175 British youths. Results show that parental distress at year t-1 is an important determinant of child’s life satisfaction in the current year. This is true for boys and girls, although boys do not appear to be affected by maternal distress levels. The results also indicated that the child’s own life satisfaction is related with their father’s distress levels in the following year, regardless of the gender of the child. Finally, we examined whether the underlying transmission correlation is due to shared social environment, empathic reactions, or transmission via parent-child interaction

    Menstruation as a Weapon of War – The Politics of the Bleeding Body for Women on Political Protest at Armagh Prison Northern Ireland.

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    This article draws on the voices of women political prisoners who were detained at Armagh Prison during the period of the Troubles or the Conflict in Northern Ireland. It focuses on women who undertook an extraordinary form of protest against the prison authorities during the 1980s, known as the No Wash Protest. As the prisoners were prevented from leaving their cells by prison officer either to wash or to use the toilet, the women, living in the midst of their own dirt and body waste, added menstrual blood as a form of protest

    Control of Dynamical Localization

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    Control over the quantum dynamics of chaotic kicked rotor systems is demonstrated. Specifically, control over a number of quantum coherent phenomena is achieved by a simple modification of the kicking field. These include the enhancement of the dynamical localization length, the introduction of classical anomalous diffusion assisted control for systems far from the semiclassical regime, and the observation of a variety of strongly nonexponential lineshapes for dynamical localization. The results provide excellent examples of controlled quantum dynamics in a system that is classically chaotic and offer new opportunities to explore quantum fluctuations and correlations in quantum chaos.Comment: 9 pages, 7 figures, to appear in Physical Review

    Discourse markers activate their, <i>like</i>, cohort competitors

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    Speech in everyday conversations is riddled with discourse markers (DMs), such as well, you know, and like. However, in many lab-based studies of speech comprehension, such DMs are typically absent from the carefully articulated and highly controlled speech stimuli. As such, little is known about how these DMs influence online word recognition. The present study specifically investigated the online processing of DM like and how it influences the activation of words in the mental lexicon. We specifically targeted the cohort competitor (CC) effect in the Visual World Paradigm: Upon hearing spoken instructions to “pick up the beaker,” human listeners also typically fixate—next to the target object—referents that overlap phonologically with the target word (cohort competitors such as beetle; CCs). However, several studies have argued that CC effects are constrained by syntactic, semantic, pragmatic, and discourse constraints. Therefore, the present study investigated whether DM like influences online word recognition by activating its cohort competitors (e.g., lightbulb). In an eye-tracking experiment using the Visual World Paradigm, we demonstrate that when participants heard spoken instructions such as “Now press the button for the, like … unicycle,” they showed anticipatory looks to the CC referent (lightbulb)well before hearing the target. This CC effect was sustained for a relatively long period of time, even despite hearing disambiguating information (i.e., the /k/ in like). Analysis of the reaction times also showed that participants were significantly faster to select CC targets (lightbulb) when preceded by DM like. These findings suggest that seemingly trivial DMs, such as like, activate their CCs, impacting online word recognition. Thus, we advocate a more holistic perspective on spoken language comprehension in naturalistic communication, including the processing of DMs

    The Gestalt of functioning in autism revisited: First revision of the International Classification of Functioning, Disability and Health Core Sets

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    Functioning is a construct capturing how an individual’s engagement in everyday life emerges from the interaction between the individual and their environment. The World Health Organization’s International Classification of Functioning, Disability and Health (ICF) provides a biopsychosocial framework of functioning. Previously, the ICF was adapted for use in autism by developing Core Sets, a selection of ICF codes from the entire classification for specific conditions. Here, we present the first revision of the ICF of the Core sets for autism from a Delphi-like technique, based on evidence from Core Sets validation/linking studies, stakeholder feedback, and the development and piloting of the autism ICF Core Sets platform. Two ICF second-level codes were removed, and 12 were added to the comprehensive autism Core Set. The added codes reflect body functions in various sensory domains, fine hand use, and environmental factors. Changes were extensive for the age-appropriate brief Core Sets where ICF codes from the initial Core Sets were added or removed. The revisions conducted indicate a continued need for regularly updating Core Sets, based on empirical evidence and stakeholder involvement. We recommend the updated Core Sets for future use in autism research and practice in different age groups and contexts

    The challenge of rural life nostalgia: barriers in redevelopment of Malay Reserve Land (MRL) in Klang Valley

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    The development of Malay reserve land is a nationwide issue which can be overcome through better understanding of the existing barriers. While many barriers have been examined, the challenges relating to land owner expectations and preferences has not been thoroughly examined. Using Kg Sungai Penchala in the capital city Kuala Lumpur as a case, this research used a structured interview survey of 258 respondents representing both owners and tenants. Statistical analysis demonstrates that majority of the land owners (individuals) rejected the idea to further develop the land. The land owners preferred to maintain the village status quo and they were satisfied with the current development level in the village. Only a minority of respondents agreed that the land should be developed and instead perceived that re-development of this Malay Reserve Land of Kg Sungai Penchala would be able to raise their quality of life. The restriction is much preferred by the land owners who preferred the current style of village living. Thus, immediate re-development of the area is not warranted and the preference of the land owners represents a strong barrier
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