9 research outputs found
Fitting the integrated Spectral Energy Distributions of Galaxies
Fitting the spectral energy distributions (SEDs) of galaxies is an almost
universally used technique that has matured significantly in the last decade.
Model predictions and fitting procedures have improved significantly over this
time, attempting to keep up with the vastly increased volume and quality of
available data. We review here the field of SED fitting, describing the
modelling of ultraviolet to infrared galaxy SEDs, the creation of
multiwavelength data sets, and the methods used to fit model SEDs to observed
galaxy data sets. We touch upon the achievements and challenges in the major
ingredients of SED fitting, with a special emphasis on describing the interplay
between the quality of the available data, the quality of the available models,
and the best fitting technique to use in order to obtain a realistic
measurement as well as realistic uncertainties. We conclude that SED fitting
can be used effectively to derive a range of physical properties of galaxies,
such as redshift, stellar masses, star formation rates, dust masses, and
metallicities, with care taken not to over-interpret the available data. Yet
there still exist many issues such as estimating the age of the oldest stars in
a galaxy, finer details ofdust properties and dust-star geometry, and the
influences of poorly understood, luminous stellar types and phases. The
challenge for the coming years will be to improve both the models and the
observational data sets to resolve these uncertainties. The present review will
be made available on an interactive, moderated web page (sedfitting.org), where
the community can access and change the text. The intention is to expand the
text and keep it up to date over the coming years.Comment: 54 pages, 26 figures, Accepted for publication in Astrophysics &
Space Scienc
The effectiveness of communication groups in day nurseries
This project, run by a speech and language therapist and a clinical psychologist, took place in three inner city day nurseries. A group of children over whose communication there was concern were assessed on both formal (verbal and nonâverbal) and informal (observational) measures. At each nursery these children were divided into two matched groups: intervention and control. The intervention consisted of communication groups run jointly with nursery staff. These small groups focused on promoting communication through play. On reassessment the children attending the communication groups had made significantly more improvement than the controls on both formal and informal measures. In particular, the number and quality of children's interactions, their underlying ability to focus on tasks and their knowledge of basic concepts appeared to benefit from the intervention. The study, therefore, provides strong evidence for the efficacy of such interventions in enhancing communication development in a realâlife setting. Cette Ă©tude, effectuĂ©e par un orthophoniste et un psychologue clinique, s'est dĂ©roulĂ©e dans trois crĂšches de jour urbaines. Un groupe d'enfants, dont la capacitĂ© Ă communiquer causait des inquiĂ©tudes, a Ă©tĂ© Ă©valuĂ© a la fois selon des critĂšres formels (verbaux at non verbaux) et informels (fondĂ©s sur l'observation). Dans chaque crĂšche ces enfants ont Ă©tĂ© divisĂ©s en deux groupes semblables: un groupe d'intervention et un de contrÇle. L'intervention consistait en l'Ă©tablissement de petits groupes de communication gĂ©rĂ©s en association avec le personnel des crĂšches. Ces petits groupes avient pour but de promouvoir la communication Ă travers l'activitĂ© ludique. Une Ă©valuation ultĂ©rieure a permis de voir des amĂ©liorations significativement plus importantes chez les enfants qui avaient pris part aux groupes de communication qu'au sein des groupes de contrÇle, en ce qui concernait tant les critĂšres formels qu'informels. En particulier, le nombre et la qualitĂ© des interactions entre enfants, leur capacitĂ© intrinsĂšque de s'appliquer Ă des tÇches et leurs connaissances de concepts fondamentaux semblent avoir bĂ©nĂ©ficiĂ© de l'intervention. Par consĂ©quent l'Ă©tude confirme nettement l'efficacitĂ© de ce type d'interventions pour le dĂ©veloppement de la communication dans le cadre de la vie rĂ©elle. Dieses Projekt wurde von einem Sprachtherapeuten und einem klinischen Psychologen in drei Kindergarten des inneren Stadtbereiches durchgefĂŒhrt. Eine Gruppe von Kindern, deren Kommunikationsvermögen zur Sorge AnlaĂ gab, wurde hinsichtlich formaler (verbal und nichtverbal) und informeller Kriterien (Beobachtungen) bewertet. In jeder TagesstĂ€tte wurden die Kinder in gepaarte Gruppen eingeteilt: Kontrollgruppe und Behandlungsgruppe. Die Behandlungfand in Kommunikationsgruppen statt, die wir zusammen mit dem Kindergartenpersonal leiteten. Ziel dieser kleinen Gruppen war die Förderung der Kommunikation beim Spiel. Eine Folgeuntersuchung zeigte eine signifikant stĂ€rkere Besserung der Kommunikation hinsichtlich der formalen und der informellen BewertungsmaĂe bei den Kindern in den Kommunikationsgruppen. Insbesondere wurden die Anzahl und die QualitĂ€t der Interaktionen, die FĂ€higkeit der Kinder, sich auf Aufgaben zu konzentrieren, und das VerstĂ€ndnis von grundlegenden Begriffen durch die Behandlung positiv beeinfluĂt. Die Untersuchung bietet daher positive Evidenz fĂŒr die Wirksamkeit solcher Behandlungsmethoden bei der Förderung der Kommunikationsentwicklung im Alltag. 1993 Royal College of Speech & Language Therapist