New magnetic field measurements of beta Cephei stars and Slowly Pulsating B stars

We present the results of the continuation of our magnetic survey with FORS1 at the VLT of a sample of B-type stars consisting of confirmed or candidate beta Cephei stars and Slowly Pulsating B stars. Roughly one third of the studied beta Cephei stars have detected magnetic fields. The fraction of magnetic Slowly Pulsating B and candidate Slowly Pulsating B stars is found to be higher, up to 50%. We find that the domains of magnetic and non-magnetic pulsating stars in the H-R diagram largely overlap, and no clear picture emerges as to the possible evolution of the magnetic field across the main sequence.Comment: 2 pages, 1 figure, to appear in Proceedings of IAU Symposium 259 "Cosmic Magnetic Fields: from Planets, to Stars and Galaxies", Tenerife, Spain, November 3-7, 200

Lazy Model Expansion: Interleaving Grounding with Search

Finding satisfying assignments for the variables involved in a set of constraints can be cast as a (bounded) model generation problem: search for (bounded) models of a theory in some logic. The state-of-the-art approach for bounded model generation for rich knowledge representation languages, like ASP, FO(.) and Zinc, is ground-and-solve: reduce the theory to a ground or propositional one and apply a search algorithm to the resulting theory. An important bottleneck is the blowup of the size of the theory caused by the reduction phase. Lazily grounding the theory during search is a way to overcome this bottleneck. We present a theoretical framework and an implementation in the context of the FO(.) knowledge representation language. Instead of grounding all parts of a theory, justifications are derived for some parts of it. Given a partial assignment for the grounded part of the theory and valid justifications for the formulas of the non-grounded part, the justifications provide a recipe to construct a complete assignment that satisfies the non-grounded part. When a justification for a particular formula becomes invalid during search, a new one is derived; if that fails, the formula is split in a part to be grounded and a part that can be justified. The theoretical framework captures existing approaches for tackling the grounding bottleneck such as lazy clause generation and grounding-on-the-fly, and presents a generalization of the 2-watched literal scheme. We present an algorithm for lazy model expansion and integrate it in a model generator for FO(ID), a language extending first-order logic with inductive definitions. The algorithm is implemented as part of the state-of-the-art FO(ID) Knowledge-Base System IDP. Experimental results illustrate the power and generality of the approach

“Sheep week” - giving students a taste of sheep farming and rural life in central Queensland

The location of the Townsville Campus of James Cook University, being at least 4 hours driving from any commercial sheep properties, creates significant challenges as far as the theoretical and practical teaching of small ruminant medicine and production is concerned. A week-long field trip to central west Queensland gives students the opportunity to have a first-hand look of wool, sheep and goat meat production systems. Students visit a range of high-profile producers and learn about some of the important animal health and production concerns that occur on-farm. A strong emphasis is placed on the understanding of grazing systems and grazing land management issues in western Queensland. During this field trip, the students stay at the Australian Agricultural College in Longreach. They attend a range of seminars presented by DAFF staff and local veterinarians, including several modules from the Making More from Sheep – Best Practice Manual. They also have practical skill sessions in body condition scoring, soundness evaluation, pregnancy scanning, tail docking, wool classing, and carrying out field post mortems. Time permitting, they also spend some time at DAFF’s Rosebank Research Station. For many students, this is their first experience of outback Queensland, and it is expected that this exercise will encourage students to seek employment away from metropolitan areas and be comfortable and content with working in rural locations

Current blowfly control practices in Victoria

[Extract] The planned phase-out of mulesing by 2010 has forced the development of alternative methods to control blowfly strike. At the Mackinnon Project we have taken on the challenge to optimize control strategies for blowfly strike. In order to do this, we firstly need to understand how producers manage flystrike nowadays. The last major survey on blowfly strike in south-eastern Australia was done in 1982, so there was a need to determine the current blowfly control practices in this region

Socio-economic status as a proxy for input quality in bilingual children?

This study investigates the effect of socioeconomic status (SES) as a proxy for input quality, in predicting language proficiency. Different operationalizations of SES are compared, including simple measures (parental education and parental occupation) and complex measures combining two dimensions (among parental education, parental occupation, and deprivation risk). All significantly predict overall English proficiency scores in a diverse group of 5- to 7-year-olds acquiring English and another language. The most informative SES measure in that respect is shown to be a complex measure combining parental education and parental occupation. That measure is used in a second set of analyses showing that different aspects of language are affected differently by variations in SES and in language exposure

Individual differences in the production of referential expressions: the effect of language proficiency, language exposure and executive function in bilingual and monolingual children

One hundred and seventy-two English-speaking 5- to 7-year-olds participated in a referential communication task where we manipulated the linguistic mention and the visual presence of a competitor alongside a target referent. Eighty-seven of the children were additionally exposed to a language other than English (bilinguals). We measured children’s language proficiency, verbal working memory (WM), cognitive control skills, family SES, and relative amount of cumulative exposure and use of the home language for the bilinguals. Children’s use of full Noun Phrases (NPs) to identify a target referent was predicted by the visual presence of a competitor more than by its linguistic mention. Verbal WM and proficiency predicted NP use, while cognitive control skills predicted both the ability to use expressions signalling discourse integration and sensitivity to the presence of a discourse competitor, but not of a visual competitor. Bilingual children were as informative as monolingual children once proficiency was controlled for