6,438 research outputs found
The Scalar Meson f0(980) in Heavy-Meson Decays
A phenomenological analysis of the scalar meson f0(980) is performed that
relies on the quasi-two body decays D and Ds -> f0(980)P, with P=pi, K. The
two-body branching ratios are deduced from experimental data on D or Ds -> pi
pi pi, K Kbar pi and from the f0(980) -> pi+ pi- and f0(980) -> K+ K- branching
fractions. Within a covariant quark model, the scalar form factors F0(q2) for
the transitions D and Ds -> f0(980) are computed. The weak D decay amplitudes,
in which these form factors enter, are obtained in the naive factorization
approach assuming a quark-antiquark state for the scalar and pseudoscalar
mesons. They allow to extract information on the f0(980) wave function in terms
of u-ubar, d-dbar and s-sbar pairs as well as on the mixing angle between the
strange and non-strange components. The weak transition form factors are
modeled by the one-loop triangular diagram using two different relativistic
approaches: covariant light-front dynamics and dispersion relations. We use the
information found on the f0(980) structure to evaluate the scalar and vector
form factors in the transitions D and Ds -> f0(980), as well as to make
predictions for B and Bs -> f0(980), for the entire kinematically allowed
momentum range of q2.Comment: 45 pages, 9 figures and 9 tables. The use of dispersion relations to
calculate the weak transition form factors is better justified. A more
extensive discussion on the strange and non-strange flavor content mixing is
introduced. Results unchanged. Version to appear in Phys. Rev.
Post-Foucauldian governmentality: what does it offer critical social policy analysis?
This article considers the theoretical perspective of post-Foucauldian governmentality, especially the insights and challenges it poses for applied researchers within the critical social policy tradition. The article firstly examines the analytical strengths of this approach to understanding power and rule in contemporary society, before moving on to consider its limitations for social policy. It concludes by arguing that these insights can be retained, and some of the weaknesses overcome, by adopting a ârealist governmentalityâ approach (Stenson 2005, 2008). This advocates combining traditional discursive analysis with more ethnographic methods in order to render visible the concrete activity of governing, and unravel the messiness, complexity and unintended consequences involved in the struggles around subjectivity
Neonatal research:the parental perspective
Objectives: To investigate the recollections of parents consenting for their infants to be research subjects and determine their views about the need for consent. Subjects: Parents of 154 sick newborn infants enrolled in a randomised trial in the early neonatal period. All parents had given written consent and received printed information. Methods: A questionnaire and accompanying letter was sent to the parental home 18 months later. Non-responders were sent a further questionnaire and letter. Results: Response rate was 64% (99/154). Some respondents (12%) did not remember being asked to consent to their baby joining a study, and a further 6% were unsure. Most of the respondents (79%) were happy, 13% neutral, and 8% unhappy with their decision to give consent. None felt heavy pressure to agree. Entering the trial caused 24% of respondents to feel more anxious, 56% neutral, and 20% less anxious about their baby. Most of the respondents (83%) would be unhappy to forgo the consent process for trials passed by the institutional ethics committee. Conclusions: A significant proportion of parents who give written consent for a trial in the early neonatal period do not later remember having done so. Parents who have had experience of neonatal research would be unhappy for their baby to be enrolled in a study that had ethics committee approval without their consent being obtained
Atlantic water variability on the SE Greenland continental shelf and its relationship to SST and bathymetry
Author Posting. Š American Geophysical Union, 2013. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 118 (2013): 847â855, doi:10.1029/2012JC008354.Interaction of warm, Atlantic-origin water (AW) and colder, polar origin water (PW) advecting southward in the East Greenland Current (EGC) influences the heat content of water entering Greenland's outlet glacial fjords. Here we use depth and temperature data derived from deep-diving seals to map out water mass variability across the continental shelf and to augment existing bathymetric products. We compare depths derived from the seal dives with the IBCAO Version 3 bathymetric database over the shelf and find differences up to 300âm near several large submarine canyons. In the vertical temperature structure, we find two dominant modes: a cold mode, with the typical AW/PW layering observed in the EGC, and a warm mode, where AW is present throughout the water column. The prevalence of these modes varies seasonally and spatially across the continental shelf, implying distinct AW pathways. In addition, we find that satellite sea surface temperatures (SST) correlate significantly with temperatures in the upper 50âm (Râ=â0.54), but this correlation decreases with depth (Râ=â0.22 at 200âm), and becomes insignificant below 250âm. Thus, care must be taken in using SST as a proxy for heat content, as AW mainly resides in these deeper layers.Funding for this work came from National
Science Foundation OPP grant 0909373 and OCE grant 1130008, plus the
WHOI Arctic Research Initiative. The Greenland Institute of Natural
Resources and the Department of Fisheries and Oceans, Canada, supported
the seal tagging logistics.2013-08-2
Who are these youths? Language in the service of policy
In the 1990s policy relating to children and young people who offend developed as a result of the interplay of political imperatives and populist demands. The âresponsibilisationâ of young offenders and the âno excusesâ culture of youth justice have been âmarketedâ through a discourse which evidences linguistic changes. This article focuses on one particular area of policy change, that relating to the prosecutorial decision, to show how particular images of children were both reflected and constructed through a changing selection of words to describe the non-adult suspect and offender. In such minutiae of discourse can be found not only the signifiers of public attitudinal and policy change but also the means by which undesirable policy developments can be challenged
Seasonal variability of the warm Atlantic Water layer in the vicinity of the Greenland shelf break
The warmest water reaching the east and west coast of Greenland is found between 200?m and 600?m. Whilst important for melting Greenland's outlet glaciers, limited winter observations of this layer prohibit determination of its seasonality. To address this, temperature data from Argo profiling floats, a range of sources within the World Ocean Database and unprecedented coverage from marine-mammal borne sensors have been analysed for the period 2002-2011. A significant seasonal range in temperature (~1-2?°C) is found in the warm layer, in contrast to most of the surrounding ocean. The phase of the seasonal cycle exhibits considerable spatial variability, with the warmest water found near the eastern and southwestern shelf-break towards the end of the calendar year. High-resolution ocean model trajectory analysis suggest the timing of the arrival of the year's warmest water is a function of advection time from the subduction site in the Irminger Basin
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