Application of the Trend Filtering Algorithm on the MACHO Database

Due to the strong effect of systematics/trends in variable star observations, we employ the Trend Filtering Algorithm (TFA) on a subset of the MACHO database and search for variable stars. TFA has been applied successfully in planetary transit searches, where weak, short-lasting periodic dimmings are sought in the presence of noise and various systematics (due to, e.g., imperfect flat fielding, crowding, etc). These latter effects introduce colored noise in the photometric time series that can lead to a complete miss of the signal. By using a large number of available photometric time series of a given field, TFA utilizes the fact that the same types of systematics appear in several/many time series of the same field. As a result, we fit each target time series by a (least-square-sense) optimum linear combination of templates and frequency-analyze the residuals. Once a signal is found, we reconstruct the signal by employing the full model, including the signal, systematics and noise. We apply TFA on the brightest ~5300 objects from subsets of each of the MACHO Large Magellanic Cloud fields #1 and #79. We find that the Fourier frequency analysis performed on the original data detect some 60% of the objects as trend-dominated. This figure decreases essentially to zero after using TFA. Altogether, We detect 387 variables in the two fields, 183 of which would have remained undetected without using TFA. Where possible, we give preliminary classification of the variables found.Comment: 12 pages, 15 figures, 3 tables with online material; to appear in Astronomy and Astrophysic

Upper limits on liquid water in the Venus atmosphere

Upper limits on liquid water in Venus atmosphere due to presence of hydrogen chlorid

Response of mouse epidermal cells to single doses of heavy-particles

The survival of mouse epidermal cells to heavy-particles has been studied In Vivo by the Withers clone technique. Experiments with accelerated helium, lithium and carbon ions were performed. The survival curve for the helium ion irradiations used a modified Bragg curve method with a maximum tissue penetration of 465 microns, and indicated that the dose needed to reduce the original cell number to 1 surviving cell/square centimeters was 1525 rads with a D sub o of 95 rads. The LET at the basal cell layer was 28.6 keV per micron. Preliminary experiments with lithium and carbon used treatment doses of 1250 rads with LET's at the surface of the skin of 56 and 193 keV per micron respectively. Penetration depths in skin were 350 and 530 microns for the carbon and lithium ions whose Bragg curves were unmodified. Results indicate a maximum RBE for skin of about 2 using the skin cloning technique. An attempt has been made to relate the epidermal cell survival curve to mortality of the whole animal for helium ions

Non-thermal X-ray Emission: An Alternative to Cluster Cooling Flows?

We report the results of experiments aimed at reducing the major problem with cooling flow models of rich cluster X-ray sources: the fact that most of the cooled gas or its products have not been found. Here we show that much of the X-ray emission usually attributed to cooling flows can, in fact, be modeled by a power-law component which is indicative of a source(s) other than thermal bremsstrahlung from the intracluster medium. We find that adequate simultaneous fits to ROSAT PSPCB and ASCA GIS/SIS spectra of the central regions of ten clusters are obtained for two-component models that include a thermal plasma component that is attributable to hot intracluster gas and a power-law component that is likely generated by compact sources and/or extended non-thermal emission. For five of the clusters that purportedly have massive cooling flows, the best-fit models have power-law components that contribute $\sim$ 30 % of the total flux (0.14 - 10.0 keV) within the central 3 arcminutes. Because cooling flow mass deposition rates are inferred from X-ray fluxes, our finding opens the possibility of significantly reducing cooling rates.Comment: 11 pages, 3 figures, emulateapj style. Accepted for publication in Ap

Large angle Beamstrahlung as a beam-beam monitoring tool

A novel method to measure the beam-beam interaction in e+e- colliders is presented.Comment: 17 pages, four figures, to be published in Nuclear Instruments and Method

Music in early education and care settings for communication and language support

Musical activities are often an integral part of the home life of young children and their caregivers. Activities include songs and rhymes that coordinate the daily routine, as well as opportunities for learning and engagement in a wider world. Music groups for caregivers and young children are also included within programmes of activities for families in early education and care settings. Additionally, such settings may have specific targets and outcomes that seek to improve the life chances of young children in disadvantaged circumstances; one key target may be the development of young children’s communication skills. There is the suggestion, based on evidence from large-scale studies, that young children from disadvantaged backgrounds lag behind their more advantaged peers in language skills. Music can help children develop language and the associated skills necessary to be ready for school. In the early education and care setting context, it can be seen that music group sessions may serve various non-music targets and outcomes. This chapter overviews the evidence that appropriate musical activities are beneficial to learning and language development, challenging a view that words are the best starting point for communication. It seeks to offer a model of an effective musical pedagogical approach, developed through action research with an interdisciplinary team of early childhood music-arts practitioners and speech and language therapists for caregivers and young children in early care settings. The chapter aids reflection on children’s emerging communication through musical activities, as well as some practical ideas for working with children with communication difficulties. Finally, the main findings from two projects are presented as practical implications, seeking to contribute new knowledge about working with children and their caregivers through music in early education and care settings

The preparation of music teachers in Brazil and England: reflections on teaching practice models

This paper examines and compares teaching practice models of three music teacher training courses originating from Brazil and England, as well as addressing issues regarding the initial preparation of the music teacher in both countries. Activity theory was employed as a theoretical framework to explain the related factors involved in both models’ implementation. A number of challenges were indentified such as: (i) how to balance the theoretical and practical dimensions of the curriculum; (ii) the quest for mechanisms for the transferral of the pedagogical and musical instrument knowledge acquired by students to music teaching practice contexts; and (iii) the absence of a specialist music teacher as mentors in some educational contexts. Findings showed that there is diversity in teaching practice models due to different educational and technological contexts employed

Carbon dioxide tolerance studies

Human tolerance to exposure of carbon dioxide environmen