2,549 research outputs found

    The Optical/Near-IR Colors of Broad Absorption Line Quasars, Including the Candidate Radio-Loud BAL Quasar 1556+3517

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    A candidate radio-loud broad absorption line quasar (RLBAL) has been reported by Becker et al. (1997). We present JHK observations of this object and three other radio-detected BALs taken with the new Michigan-Dartmouth-MIT/Ohio State/Aladdin IR Camera (MOSAIC) on the KPNO 4-meter. The candidate RLBAL 1556+3517 has B-K=6.63, redder than all but one or two known z>1 quasars. This strongly suggests the observed continuum of this quasar is reddened by dust. Even when this extreme reddening is taken into account 1556+3517 is still probably radio-loud, although near-IR spectroscopy to measure its Balmer decrement will be needed to verify this. In addition, since it is a flat-spectrum object, VLBI observations to determine the extent (if any) to which beaming affects our estimate of its radio luminosity will be needed before 1556+3517 can be unequivocally declared a radio-loud BAL. We also use our data and data from the literature to show that optically selected BALs as a class have B-K colors consistent with the observed distribution for optically selected quasars as a whole. Thus there is currently no evidence that the tendency of optically selected BALs to be preferentially radio-intermediate (Hooper, Francis, & Impey 1993) is due to extinction artificially lowering estimated BAL optical luminosities. However, as most quasar surveys, both radio and optical, would be insensitive to a population of reddened radio-quiet BALs, the existence of a large population of reddened BALs similar to 1556+3517 cannot yet be ruled out.Comment: Accepted to ApJ Letters; 10 pages including 1 figure and 2 tables. This version somewhat revised from initial submission, with a better figur

    Layer by layer - Combining Monads

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    We develop a method to incrementally construct programming languages. Our approach is categorical: each layer of the language is described as a monad. Our method either (i) concretely builds a distributive law between two monads, i.e. layers of the language, which then provides a monad structure to the composition of layers, or (ii) identifies precisely the algebraic obstacles to the existence of a distributive law and gives a best approximant language. The running example will involve three layers: a basic imperative language enriched first by adding non-determinism and then probabilistic choice. The first extension works seamlessly, but the second encounters an obstacle, which results in a best approximant language structurally very similar to the probabilistic network specification language ProbNetKAT

    Far-infrared observations of young clusters embedded in the R Coronae Austrinae and RHO Ophiuchi dark clouds

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    Multicolor far infrared maps in two nearby dark clouds, R Coronae Austrinae and rho Ophiuchi, were made in order to investigate the individual contribution of low mass stars to the energetics and dynamics of the surrounding gas and dust. Emission from cool dust associated with five low mass stars in Cr A and four in rho Oph was detected; their far infrared luminosities range from 2 far infrared luminosities L. up to 40 far infrared luminosities. When an estimate of the bolometric luminosity was possible, it was found that typically more than 50% of the star's energy was radiated longward of 20 micrometers. meaningful limits to the far infrared luminosities of an additional eleven association members in Cr A and two in rho Oph were also obtained. The dust optical depth surrounding the star R Cr A appears to be asymmetric and may control the dynamics of the surrounding molecular gas. The implications of the results for the cloud energetics and star formation efficiency in these two clouds are discussed

    A double-edged sword: the merits and the policy implications of Google Translate in higher education

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    Machine translation, specifically Google Translate is freely available on a number of devices, and is improving in its ability to provide grammatically accurate translations. This development has the potential to provoke a major transformation in the internationalisation process at universities, since students may be, in the future, able to use technology to circumvent traditional language learning processes. While this is a potentially empowering move that may facilitate academic exchange and the diversification of the learner and researcher community at an international level, it is also a potentially problematic issue in two main respects. Firstly, the technology is at present unable to align to the socio-linguistic aspects of university level writing and may be misunderstood as a remedy to lack of writer language proficiency – a role it is not able to fulfil. Secondly, it introduces a new dimension to the production of academic work that may clash with Higher Education policy and, thus, requires legislation, in particular in light issues such as plagiarism and academic misconduct. This paper considers these issues against the background of English as a Global Lingua Franca, and argues two points. First of these is that HEIs need to develop an understanding and code of practice for the use of this technology. Secondly, three strands of potential future research will be presente

    Globalisation, neo-liberalism and vocational learning: the case of English further education colleges

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    Further education (FE) has traditionally been a rather unspectacular activity. Lacking the visibility of schools or the prestige of universities, for the vast majority of its existence FE has had a relatively low profile on the margins of English education. Over recent years this situation has altered significantly and further education has undergone profound change. This paper argues that a combination of related factors – neo-liberalism, globalisation, and dominant discourses of the knowledge economy – has acted in synergy to transform FE into a highly performative and marketised sector. Against this backdrop, further education has been assigned a particular role based upon certain narrow and instrumental understandings of skill, employment and economic competitiveness. The paper argues that, although it has always been predominantly working class in nature, FE is now, more than ever, positioned firmly at the lower end of the institutional hierarchy in the highly class-stratified terrain of English education

    Explaining unexplained pain to fibromyalgia patients: finding a narrative that is acceptable to patients and provides a rationale for evidence based interventions

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    As the cause of fibromyalgia is controversial, communicating with patients can be challenging, particularly if the patient adopts the narrative ‘I am damaged and so I need a more powerful pain killer’. Research shows that providing patients with alternative narratives can be helpful, but it remains unclear what particular narratives are most acceptable to patients and at the same time provide a rationale for evidence based psychological and exercise interventions. This article described the development of a new narrative and the written comments made about the narrative by fibromyalgia patients. The narrative derives from a complexity theory model and provides an alternative to biogenic and psychogenic models. The model was presented to 15 patients whose comments about comprehensibility led to the final format of the narrative. In the final form, the body is presented as ‘a very, very clever computer’ where fibromyalgia is caused by a software rather than a hardware problem. The software problem is caused by the body adapting when people have to ‘keep going’ despite ‘stop signals’, such as pain and fatigue. The narrative provides a rationale for engaging in psychological and exercise interventions as a way of correcting the body’s software. This way of explaining fibromyalgia was evaluated by a further 25 patients attending a 7-week ‘body reprogramming’ intervention, where the therapy was presented as correcting the body’s software, and included both exercise and psychological components. Attendance at the course was 85%. Thematic analysis of written patient feedback collected after each session showed that patients found the model believable and informative, it provided hope and was empowering. Patients also indicated that they had started to implement lifestyle change with perceived benefit. Fibromyalgia patients appear to respond positively to a technology-derived narrative based on the analogy of the body as a computer

    Assessing the Factorial Validity of the Attitudes and Belief Scale 2-Abbreviated Version: A Call for the Development a Gold Standard Method of Measuring Rational and Irrational Beliefs

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    Rational Emotive Behaviour Therapy (REBT) does not possess a measure of rational and irrational beliefs that meets internationally recognised standards for acceptable psychometric properties. Without such a measure the theory/practice of REBT cannot be rigorously evaluated, thus undermining its scientific veracity. The current study investigates the validity and reliability of a recently developed measure of rational and irrational beliefs: the Attitudes and Belief Scale 2-Abbreviated Version (ABS-2-AV). University students from three countries completed the ABS-2-AV (N = 397). An alternative models framework using confirmatory factor analysis indicated that a theoretically consistent eight-factor model of the ABS-2-AV provided the best fit of the data. A number of post-hoc modifications were required in order to achieve acceptable model fit results, and these modifications revealed important methodological limitations with the ABS-2-AV. Results indicated that the validity of the ABS-2-AV was undermined due to items measuring both the psychological process of interest (rational and irrational beliefs) and the context in which these beliefs processes are presented. This is a serious methodological limitation of the ABS-2 and all questionnaires derived from it, including the ABS-2-AV. This methodological limitation resulted in the ABS-2-AV possessing poor internal reliability. These limitations are discussed in relation to the broader REBT literature and the impact such problems have on research and practice. A call is made for REBT researchers to come together to develop a “gold standard” method of assessing rational and irrational beliefs that meets international standard for psychometric excellence
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