752 research outputs found

    Exploring the role of formal bodies of knowledge in defining a profession - The case of project management

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    Since the mid 1970s, project management associations around the world have made serious attempts to conduct themselves as professional associations. Traditional professions distinguished themselves by emphasising standards such as service to the public and competence in their field, and by ensuring that their membership meets these standards. An important element of a profession is ownership of a body of knowledge that is distinctive to the professional group. Project management associations have spent considerable time and effort in developing Bodies of Knowledge (BOKs) and their associated certification programs, and indeed the popularity of these has been notable. Yet there are problems, some relating to the broader issue of whether the project management associations really are equipped to act as professional bodies, others related to the specific challenge of agreeing the 'distinctive body of knowledge' and to the value of certification. This paper draws on insights from the rethinking project management EPSRC project as well as several separate research programs to explore the development of project management as a profession and the role of the formal BOKs in this professionalization, and to suggest a research agenda for critiquing, contributing to, and maintaining both the formal BOKs and the more general body of knowledge relevant to the needs of the discipline. © 2006

    Discovery of a Young Radio Pulsar in a Relativistic Binary Orbit

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    We report on the discovery of PSR J1141-6545, a radio pulsar in an eccentric, relativistic 5-hr binary orbit. The pulsar shows no evidence for being recycled, having pulse period P = 394 ms, characteristic age tau_c = 1.4 x 10^6 yr, and inferred surface magnetic dipole field strength B = 1.3 x 10^12 G. From the mass function and measured rate of periastron advance, we determine the total mass in the system to be (2.300 +/- 0.012) solar masses, assuming that the periastron advance is purely relativistic. Under the same assumption, we constrain the pulsar's mass to be M_p < 1.348 solar masses and the companion's mass to be M_c > 0.968 solar masses (both 99% confidence). Given the total system mass and the distribution of measured neutron star masses, the companion is probably a massive white dwarf which formed prior to the birth of the pulsar. Optical observations can test this hypothesis.Comment: 18 pages, 4 figures, Accepted for Publication in Ap

    To Binge or not To Binge: viewers’ moods and behaviors during the consumption of subscribed video streaming

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    The popularity of internet-distributed TV entertainment services, such as Netflix, has transformed TV consumption behavior. Currently, the level of control viewers have over their TV experiences, along with the release of com plete seasons at once, are some of the factors that stimulate the so-called binge watching phenomenon (the consumption of several episodes of a program in a single sitting). Most of binge-watching studies have focused on viewers’ habits and health effects. This paper presents a study that relates to viewers’ behaviors and moods. It was carried out with 13 young participants at their home, watching online content, collecting physiological, inertial, and self-reported data. We iden tify and compare binge-watching with non-binge-watching behaviors. Our results suggest that while viewers recur to online serial entertainment in pursuit of lei sure related needs, such as relaxation, relief from boredom and escapism, the act of binge-watching tends to make them feel rather unsatisfied with no change in Arousal. Nevertheless, in binge-watching the Positive Affect increases while the Negative decreases. Moreover, watching a single episode only, tends to result in increased arousal and but not necessarily in increased satisfaction. This prelimi nary finding can be the starting point of fruitful future investigations on unpack ing further motives and nuances from this outcome.info:eu-repo/semantics/publishedVersio

    Glaucoma in primates: cytochrome oxidase reactivity in parvo- and magnocellular

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    PURPOSE. To evaluate the differential effects of ganglion cell depletion from experimental glaucoma on the relative metabolic activities of neurons in the parvo (P)-and magno (M)-cellular visual pathways of the macaque visual system. METHODS. Monocular experimental glaucoma was induced in monkeys (Macaca mulatta and M. fascicularis) by applying a laser to the trabecular meshwork to increase intraocular pressure (IOP). After other behavioral and electrophysiological studies, the lateral geniculate nuclei (LGNs) and the primary visual cortices were analyzed for functional afference from surviving ganglion cells, indicated by cytochrome oxidase (CO) histochemistry. RESULTS. CO reactivity (COR) indicated a general reduction in neural metabolism with increasing severity of glaucoma. COR in the LGNs was reduced to the same degree in both the P-and M-cellular layers. In layer 4C␀ of the V1 cortex, the reactivity was always reduced more than in the layer 4C␣ division. CONCLUSIONS. Experimental glaucoma in monkeys reduces visual afference to the central nervous system, thereby reducing the metabolic drive as indicated by COR. The detrimental effect of glaucoma did not appear to be any greater for the M-cell, rather than the P-cell pathway in the LGN or in the visual cortex. Both are affected by the duration and severity of the experimental glaucoma. Overall, the alterations in metabolism of neurons in the parallel visual pathways supplied by the P␣ and P␀ ganglion cells do not suggest that tests based on the functional properties of one or the other would provide optimal assessment of glaucoma. (Invest Ophthalmol Vis Sci. 2000;41: 1791-180

    Linearized stability analysis of thin-shell wormholes with a cosmological constant

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    Spherically symmetric thin-shell wormholes in the presence of a cosmological constant are constructed applying the cut-and-paste technique implemented by Visser. Using the Darmois-Israel formalism the surface stresses, which are concentrated at the wormhole throat, are determined. This construction allows one to apply a dynamical analysis to the throat, considering linearized radial perturbations around static solutions. For a large positive cosmological constant, i.e., for the Schwarzschild-de Sitter solution, the region of stability is significantly increased, relatively to the null cosmological constant case, analyzed by Poisson and Visser. With a negative cosmological constant, i.e., the Schwarzschild-anti de Sitter solution, the region of stability is decreased. In particular, considering static solutions with a generic cosmological constant, the weak and dominant energy conditions are violated, while for a0≀3Ma_0 \leq 3M the null and strong energy conditions are satisfied. The surface pressure of the static solution is strictly positive for the Schwarzschild and Schwarzschild-anti de Sitter spacetimes, but takes negative values, assuming a surface tension in the Schwarzschild-de Sitter solution, for high values of the cosmological constant and the wormhole throat radius.Comment: 16 pages, 10 figures, LaTeX2e, IOP style files. Accepted for publication in Classical and Quantum Gravit

    Bayesian inference reveals positive but subtle effects of experimental fishery closures on marine predator demographics

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    Global forage-fish landings are increasing, with potentially grave consequences for marine ecosystems. Predators of forage fish may be influenced by this harvest, but the nature of these effects is contentious. Experimental fishery manipulations offer the best solution to quantify population-level impacts, but are rare. We used Bayesian inference to examine changes in chick survival, body condition and population growth rate of endangered African penguins Spheniscus demersus in response to 8 years of alternating time–area closures around two pairs of colonies. Our results demonstrate that fishing closures improved chick survival and condition, after controlling for changing prey availability. However, this effect was inconsistent across sites and years, highlighting the difficultly of assessing management interventions in marine ecosystems. Nevertheless, modelled increases in population growth rates exceeded 1% at one colony; i.e. the threshold considered biologically meaningful by fisheries management in South Africa. Fishing closures evidently can improve the population trend of a forage-fish-dependent predator—we therefore recommend they continue in South Africa and support their application elsewhere. However, detecting demographic gains for mobile marine predators from small no-take zones requires experimental time frames and scales that will often exceed those desired by decision makers

    Spectroscopy and Time Variability of Absorption Lines in the Direction of the Vela Supernova Remnant

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    We present high resolution (R~75,000), high signal-to-noise (S/N~100) Ca II λ\lambda3933.663 and Na I λλ\lambda\lambda5889.951, 5895.924 spectra of 68 stars in the direction of the Vela supernova remnant. The spectra comprise the most complete high resolution, high S/N, optical survey of early type stars in this region of the sky. A subset of the sight lines has been observed at multiple epochs, 1993/1994 and 1996. Of the thirteen stars observed twice, seven have spectra revealing changes in the equivalent width and/or velocity structure of lines, most of which arise from remnant gas. Such time variability has been reported previously for the sight lines towards HD 72089 and HD 72997 by Danks & Sembach (1995) and for HD 72127 by Hobbs et al. (1991). We have confirmed the ongoing time variability of these spectra and present new evidence of variability in the spectra of HD 73658, HD 74455, HD 75309 and HD 75821. We have tabulated Na I and Ca II absorption line information for the sight lines in our sample to serve as a benchmark for further investigations of the dynamics and evolution of the Vela SNR.Comment: 8 pages of text, 4 tables, 16 pages of figures Accepted and to be published in ApJ

    Evaluating the effectiveness and cost effectiveness of the ‘strengthening families, strengthening communities’ group-based parenting programme: study protocol and initial insights

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    Background: Up to 20% of UK children experience socio-emotional difficulties which can have serious implications for themselves, their families and society. Stark socioeconomic and ethnic inequalities in children’s well-being exist. Supporting parents to develop effective parenting skills is an important preventive strategy in reducing inequalities. Parenting interventions have been developed, which aim to reduce the severity and impact of these difficulties. However, most parenting interventions in the UK focus on early childhood (0–10 years) and often fail to engage families from ethnic minority groups and those living in poverty. Strengthening Families, Strengthening Communities (SFSC) is a parenting programme designed by the Race Equality Foundation, which aims to address this gap. Evidence from preliminary studies is encouraging, but no randomised controlled trials have been undertaken so far. Methods/design: The TOGETHER study is a multi-centre, waiting list controlled, randomised trial, which aims to test the effectiveness of SFSC in families with children aged 3–18 across seven urban areas in England with ethnically and socially diverse populations. The primary outcome is parental mental well-being (assessed by the Warwick-Edinburgh Mental Well-Being Scale). Secondary outcomes include child socio-emotional well-being, parenting practices, family relationships, self-efficacy, quality of life, and community engagement. Outcomes are assessed at baseline, post intervention, three- and six-months post intervention. Cost effectiveness will be estimated using a cost-utility analysis and cost-consequences analysis. The study is conducted in two stages. Stage 1 comprised a 6-month internal pilot to determine the feasibility of the trial. A set of progression criteria were developed to determine whether the stage 2 main trial should proceed. An embedded process evaluation will assess the fidelity and acceptability of the intervention. Discussion: In this paper we provide details of the study protocol for this trial. We also describe challenges to implementing the protocol and how these were addressed. Once completed, if beneficial effects on both parental and child outcomes are found, the impact, both immediate and longer term, are potentially significant. As the intervention focuses on supporting families living in poverty and those from minority ethnic communities, the intervention should also ultimately have a beneficial impact on reducing health inequalities. Trial registration: Prospectively registered Randomised Controlled Trial ISRCTN15194500
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