The Canadian Hydrogen Intensity Mapping Experiment (CHIME) is a transit interferometer currently being built at the Dominion Radio Astrophysical Observatory (DRAO) in Penticton, BC, Canada. We will use CHIME to map neutral hydrogen in the frequency range 400 -800 MHz over half of the sky, producing a measurement of baryon acoustic oscillations (BAO) at redshifts between 0.8 -2.5 to probe dark energy. We have deployed a pathfinder version of CHIME that will yield constraints on the BAO power spectrum and provide a test-bed for our calibration scheme. I will discuss the CHIME calibration requirements and describe instrumentation we are developing to meet these requirements.
Microglia abnormalities may contribute to epileptogenesis in the context of neuronal involvement in TSC mouse models, but selective Tsc1 gene inactivation in microglia alone may not be sufficient to cause epilepsy, suggesting that microglia have more supportive roles in the pathogenesis of seizures in TSC.
Home range is commonly understood to be the distance from home that children are allowed to go in the outdoor environment with the term being used within various academic disciplines. Different factors influence children's home range including traffic, age, parental fears and understandings of what it means to be a good parent. Research addressing home range over different generations has identified a context of changes in the built environment, demography and technology. This paper reports results from three generations of two families in Sheffield in the north of England and confirms a reduction in four major domains: home range, variety of outdoor spaces visited; range of activities undertaken and the number of companions. Defining home rangeThe concept and term home range has been used for over forty years, originated from the field of environmental psychology (Gaster, 1995) and is generally understood as a mechanism to describe children's engagement with their outdoor environment. Some have suggested that home range is 'the distance children travel away from their home in the course of their outdoor play and leisure pursuits' (Matthews, 1992 p ) or that it is 'the sum of children's independent, voluntary encounters with the world centring on the dwelling' (Gaster, 1995,p35). Taking an understanding relating more to frequency of use Moore and Young (1978) suggested the terms habitual, frequented and occasional range. Hart identified that home range was often not imposed by parents but was 'a product of negotiation and understanding between parent and child' (Hart, 1979, p. 46). He recognised the complexity of the concept and suggested three sub-headings of free range, range with permission and range with permission and with other children. It is this complex definition that forms the basis of the research reported in this paper.The term home range seemed to fall out of use in academic discourse being replaced, to some extent,by studies about what is now called Children's Independent Mobility (CIM) with the research of Hillman et al. (1990) leading in this area. This has been followed by others exploring activity range, territorial range, daily contact space, distances children travel and places children travel to (see e.g. Spilsbury, 2005;Mackett et al., 2007;Tranter and Sharpe, 2012, Villaneuva et al. 2012).
We report on a detailed abundance study of the fairly bright slow rotators HD 30085 (A0 IV), HD 30963 (B9 III) and HD 174567 (A0 V), hitherto reported as normal stars and the sharp-lined χ Lupi A (B9 IV HgMn). In the spectra of HD 30085, HD 30963, the Hg II line at 3984Å line is conspicuous and numerous lines of silicon, manganese, chromium, titanium, iron, strontium, yttrium and zirconium appear to be strong absorbers. A comparison of the mean spectra of HD 30085 and HD 30963 with a grid of synthetic spectra for selected unblended lines having reliable updated atomic data reveals large overabundances of phosphorus, titanium, chromium, manganese, strontium, yttrium, and zirconium, barium, platinum and mercury and underabundances of helium, magnesium, scandium, nickel. The surface abundances of χ Lupi A have been rederived on the same effective temperature scale and using the same atomic data for consistency and comparison for HD 30085 and HD 30963. For HD 174567, milder deficiencies and excesses are found. The abundances of sodium, magnesium and calcium have been corrected for NLTE effects. The effective temperatures, surface gravities, low projected rotational velocities and the peculiar abundance patterns of HD 30085 and HD 30963 show that these stars are 2 new HgMn stars and should be reclassified as such. HD 174567 is most likely a new marginally Chemically Peculiar star. A list of the identifications of lines absorbing more than 2 % in the spectrum of HD 30085 is also provided.HD 30085 was ascribed a spectral type A0 IV by Cowley et al. (1969) in their survey of 1700 bright northern B9 to A9 stars with a prismatic dispersion of 125Å mm −1 around H γ . At that time, Cowley et al. (1969) did not mention any peculiarity of the spectrum. In his study of helium-weak stars, Molnar (1972) classified HD 30085 as a B9 III from 63Å mm −1 plates centered on H γ using slightly different MK criteria to assign the temperature and the luminosity class than Cowley et al. (1969) did. He did not comment on any peculiarity of the lines of Si, Sr and the metals in the spectrum of HD 30085 around H γ . HD 30085 has been detected as a fairly bright UV source with TD1 (Jamar et al. 1976), its flux steadily rising towards shorter wavelength, suggesting the star is indeed a late B star rather than an early A star. Ramella et al. (1989) report on structures in the core of the Mg II doublet at 4481Å from 12.4Å mm −1 dispersion plates. More recently, Monier et al. (2015) have reported on the presence of the Hg II line at 3984Å and several strong Mn II in the high resolution spectra of HD 30085 and provided overabundances for Mn, Fe and Hg only based on the spectrum synthesis of a few lines which clearly established the HgMn nature of this star. HD 30963 was ascribed a B9 III spectral type by Huang et al. (
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