A Continuous 100-mK Helium-Light Cooling System for MUSCAT on the LMT

The MUSCAT instrument is a large-format camera planned for installation on the Large Millimeter Telescope (LMT) in 2018. MUSCAT requires continuous cooling of several large-volume stages to sub-Kelvin temperatures, with the focal plane cooled to 100 mK. Through the use of continuous sorption coolers and a miniature dilution refrigerator, the MUSCAT project can fulfil its cryogenic requirements at a fraction of the cost and space required for conventional dilution systems. Our design is a helium-light system, using a total of only 9 litres of helium-3 across several continuous cooling systems, cooling from 4 K to 100 mK. Here we describe the operation of both the continuous sorption and the miniature dilution refrigerator systems used in this system, along with the overall thermal design and budgeting of MUSCAT. MUSCAT will represent the first deployment of these new technologies in a science-grade instrument and will prove the concept as a viable option for future large-scale experiments such as CMB-S4.Comment: Presented at 17th International Workshop on Low-Temperature Detectors. Published in Journal of Low Temperature Physics, 201

Pre-cooling a 3He/4He dilutor module with a sealed closed-cycle continuous cooler

A continuous closed cycle cooler to operate at a base temperature below 300 mK has been successfully designed and tested by Chase Research Cryogenics in collaboration with Cardiff University Astronomical Instrumentation Group. This compact, relatively low-cost unit has temperature and heat load capability of around 200 µW at 340 mK, and 400 µW at 450 mK. Here we discuss the suitability of this unit for precooling a miniature self-contained dilution module to produce a cryogen-free cooling platform capable of achieving a useful cooling power at temperatures of less than 100 mK

The Central Singularity in Spherical Collapse

The gravitational strength of the central singularity in spherically symmetric space-times is investigated. Necessary conditions for the singularity to be gravitationally weak are derived and it is shown that these are violated in a wide variety of circumstances. These conditions allow conclusions to be drawn about the nature of the singularity without having to integrate the geodesic equations. In particular, any geodesic with a non-zero amount of angular momentum which impinges on the singularity terminates in a strong curvature singularity.Comment: 17 pages; revised and corrected with improved result

A Characterisation of Strong Wave Tails in Curved Space-Times

A characterisation of when wave tails are strong is proposed. The existence of a curvature induced tail (i.e. a Green's function term whose support includes the interior of the light-cone) is commonly understood to cause backscattering of the field governed by the relevant wave equation. Strong tails are characterised as those for which the purely radiative part of the field is backscattered. With this definition, it is shown that electromagnetic waves in asymptotically flat space-times and fields governed by tail-free propagation have weak tails, but minimally coupled scalar fields in a cosmological scenario have strong tails.Comment: 17 pages, Revtex, to appear in Classical and Quantum Gravit

The acquisition of Sign Language: The impact of phonetic complexity on phonology

Research into the effect of phonetic complexity on phonological acquisition has a long history in spoken languages. This paper considers the effect of phonetics on phonological development in a signed language. We report on an experiment in which nonword-repetition methodology was adapted so as to examine in a systematic way how phonetic complexity in two phonological parameters of signed languages — handshape and movement — affects the perception and articulation of signs. Ninety-one Deaf children aged 3–11 acquiring British Sign Language (BSL) and 46 hearing nonsigners aged 6–11 repeated a set of 40 nonsense signs. For Deaf children, repetition accuracy improved with age, correlated with wider BSL abilities, and was lowest for signs that were phonetically complex. Repetition accuracy was correlated with fine motor skills for the youngest children. Despite their lower repetition accuracy, the hearing group were similarly affected by phonetic complexity, suggesting that common visual and motoric factors are at play when processing linguistic information in the visuo-gestural modality

A Comparison of the Effects of Child Management and Planned Activities Training in Five Parenting Environments

This study compared the effects of two procedures designed to enhance the extra training effects of behavioral parent training. Twenty parents of oppositional children were randomly assigned to either a child management training condition or a combined child management plus planned activities condition. A further 10 non-problem children and their parents served as a social validation group. Observations of both parent and child behavior were conducted in each of five home observation settings (breakfast time, kindy (kindergarten) or school exit, a structured playtime, bathtime, and bedtime). Both training procedures resulted in changes in both child oppositional and parent aversive behavior in all observation settings. In addition, desired positive parenting behaviors also improved in all settings. Treatment effects were maintained in all settings at 3-month follow-up. Comparisons between oppositional children following treatment and children in the social validation group showed that they each displayed similarly low levels of oppositional behavior in all settings. The implications of the results for facilitating generalized changes in behavioral parent training are discussed

Incorporating mindfulness: questioning capitalism

This paper engages with Buddhist critiques of capitalism and consumerism; and it challenges the capitalist appropriations of Buddhist techniques. We show how Buddhist modernism and Marxism/socialism can align, and how Engaged Buddhism spawns communalism and socially revolutionary impulses for sustainability and ecological responsibility within the framework of Buddhist thought and mindfulness traditions. Our case study of the Thai Asoke community exemplifies Buddhist communal mindfulness-in-action, explores successes and idiosyncrasies, and shows how communal principles can operate in such work-based communities

Sheep Updates 2005 - Part 2

This session covers seven papers from different authors: CONCURRENT SESSIONS - STRATEGIC MANAGEMENT 1.Finishing Pastoral Lambs, Peter Tozer, Patricia Harper, Janette Drew, Department of Agriculture Western Australia 2. Coating Improves Wool Quality under Mixed Farming Conditions, KE Kemper, ML Hebart, FD Brien, KS Grimson, DH Smith AMM Ramsay, South Australian Research and Development Institute 3. J. S. Richards, K.D. Atkins, T. Thompson, W. K. Murray, Australian Sheep Industry Co-operative Research Centre and NSW Department of Primary Industries, Orange Agricultural Institute, Forest Rd. Orange 4. Strategic Risk Management in the Sheep Industry, J.R.L. Hall, ICON Agriculture (JRL Hall & Co) 5. Joining Prime Lambs for the Northern End of the Market - a Systems Approach, Chris Carter, Peter Tozer, Department of Agriculture Western Australia 6. Lifetime Wool - Dry feed budgeting tool, Mike Hyder, department of Agriculture Western Australia, John Young, Farming Systems Analysis Service, Kojonup, Western Australia 7. Influence of ultrafine wool fibre curvature and blending with cashmere on attributes of knitwear, B. A. McGregor, Primary Industries Research Victoria, Department of Primary Industries, Victori

Haemoglobin mass and running time trial performance after recombinant human erythropoietin administration in trained men

<p>Recombinant human erythropoietin (rHuEpo) increases haemoglobin mass (Hbmass) and maximal oxygen uptake (v˙ O2 max).</p> <p>Purpose: This study defined the time course of changes in Hbmass, v˙ O2 max as well as running time trial performance following 4 weeks of rHuEpo administration to determine whether the laboratory observations would translate into actual improvements in running performance in the field.</p> <p>Methods: 19 trained men received rHuEpo injections of 50 IUNkg21 body mass every two days for 4 weeks. Hbmass was determined weekly using the optimized carbon monoxide rebreathing method until 4 weeks after administration. v˙ O2 max and 3,000 m time trial performance were measured pre, post administration and at the end of the study.</p> <p>Results: Relative to baseline, running performance significantly improved by ,6% after administration (10:3061:07 min:sec vs. 11:0861:15 min:sec, p,0.001) and remained significantly enhanced by ,3% 4 weeks after administration (10:4661:13 min:sec, p,0.001), while v˙ O2 max was also significantly increased post administration (60.765.8 mLNmin21Nkg21 vs. 56.066.2 mLNmin21Nkg21, p,0.001) and remained significantly increased 4 weeks after rHuEpo (58.065.6 mLNmin21Nkg21, p = 0.021). Hbmass was significantly increased at the end of administration compared to baseline (15.261.5 gNkg21 vs. 12.761.2 gNkg21, p,0.001). The rate of decrease in Hbmass toward baseline values post rHuEpo was similar to that of the increase during administration (20.53 gNkg21Nwk21, 95% confidence interval (CI) (20.68, 20.38) vs. 0.54 gNkg21Nwk21, CI (0.46, 0.63)) but Hbmass was still significantly elevated 4 weeks after administration compared to baseline (13.761.1 gNkg21, p<0.001).</p> <p>Conclusion: Running performance was improved following 4 weeks of rHuEpo and remained elevated 4 weeks after administration compared to baseline. These field performance effects coincided with rHuEpo-induced elevated v˙ O2 max and Hbmass.</p&gt