284 research outputs found
The wallaby menace in the Kimberleys
Countless thousands of Sandy Wallabies (Macropus agilis) have long been a menace to the pastoral industry in the Kimberleys. These animals eat almost the same foods as the sheep and cattle and have substantially reduced the stock-carrying capacity of the river-frontage areas where they are found in the greatest numbers. Research into control methods was commenced in 1952 when Mr. L. A. Harrison undertook some investigations designed to ascertain the best line of approach to a poisoning campaign
11 W narrow linewidth laser source at 780nm for laser cooling and manipulation of Rubidium
We present a narrow linewidth continuous laser source with over 11 Watts of
output power at 780nm, based on single-pass frequency doubling of an amplified
1560nm fibre laser with 36% efficiency. This source offers a combination of
high power, simplicity, mode quality and stability. Without any active
stabilization, the linewidth is measured to be below 10kHz. The fibre seed is
tunable over 60GHz, which allows access to the D2 transitions in 87Rb and 85Rb,
providing a viable high-power source for laser cooling as well as for
large-momentum-transfer beamsplitters in atom interferometry. Sources of this
type will pave the way for a new generation of high flux, high duty-cycle
degenerate quantum gas experiments.Comment: 5 pages, 3 figure
A Bright Solitonic Matter-Wave Interferometer
We present the first realisation of a solitonic atom interferometer. A
Bose-Einstein condensate of atoms of rubidium-85 is loaded into a
horizontal optical waveguide. Through the use of a Feshbach resonance, the
-wave scattering length of the Rb atoms is tuned to a small negative
value. This attractive atomic interaction then balances the inherent
matter-wave dispersion, creating a bright solitonic matter wave. A Mach-Zehnder
interferometer is constructed by driving Bragg transitions with the use of an
optical lattice co-linear with the waveguide. Matter wave propagation and
interferometric fringe visibility are compared across a range of -wave
scattering values including repulsive, attractive and non-interacting values.
The solitonic matter wave is found to significantly increase fringe visibility
even compared with a non-interacting cloud.Comment: 6 pages, 4 figure
Optically guided linear Mach Zehnder atom interferometer
We demonstrate a horizontal, linearly guided Mach Zehnder atom interferometer
in an optical waveguide. Intended as a proof-of-principle experiment, the
interferometer utilises a Bose-Einstein condensate in the magnetically
insensitive |F=1,mF=0> state of Rubidium-87 as an acceleration sensitive test
mass. We achieve a modest sensitivity to acceleration of da = 7x10^-4 m/s^2.
Our fringe visibility is as high as 38% in this optically guided atom
interferometer. We observe a time-of-flight in the waveguide of over half a
second, demonstrating the utility of our optical guide for future sensors.Comment: 6 pages, 3 figures. Submitted to Phys. Rev.
Precision atomic gravimeter based on Bragg diffraction
We present a precision gravimeter based on coherent Bragg diffraction of
freely falling cold atoms. Traditionally, atomic gravimeters have used
stimulated Raman transitions to separate clouds in momentum space by driving
transitions between two internal atomic states. Bragg interferometers utilize
only a single internal state, and can therefore be less susceptible to
environmental perturbations. Here we show that atoms extracted from a
magneto-optical trap using an accelerating optical lattice are a suitable
source for a Bragg atom interferometer, allowing efficient beamsplitting and
subsequent separation of momentum states for detection. Despite the inherently
multi-state nature of atom diffraction, we are able to build a Mach-Zehnder
interferometer using Bragg scattering which achieves a sensitivity to the
gravitational acceleration of with an
integration time of 1000s. The device can also be converted to a gravity
gradiometer by a simple modification of the light pulse sequence.Comment: 13 pages, 11 figure
Impact of a brief group intervention to enhance parenting and the home learning environment for children aged 6-36 months: A cluster randomised controlled trial
This is the final version of the article. Available from the publisher via the DOI in this record.This study evaluated the effectiveness of a group parenting intervention designed to strengthen the home learning environment of children from disadvantaged families. Two cluster randomised controlled superiority trials were conducted in parallel and delivered within existing services: a 6-week parenting group (51 locations randomised; 986 parents) for parents of infants (aged 6-12 months), and a 10-week facilitated playgroup (58 locations randomised; 1200 parents) for parents of toddlers (aged 12-36 months). Each trial had three conditions: intervention (smalltalk group-only); enhanced intervention with home coaching (smalltalk plus); and 'standard'/usual practice controls. Parent-report and observational measures were collected at baseline, 12 and 32 weeks follow-up. Primary outcomes were parent verbal responsivity and home learning activities at 32 weeks. In the infant trial, there were no differences by trial arm for the primary outcomes at 32 weeks. In the toddler trial at 32-weeks, participants in the smalltalk group-only trial showed improvement compared to the standard program for parent verbal responsivity (effect size (ES) = 0.16; 95% CI 0.01, 0.36) and home learning activities (ES = 0.17; 95% CI 0.01, 0.38) but smalltalk plus did not. For the secondary outcomes in the infant trial, several initial differences favouring smalltalk plus were evident at 12 weeks, but not maintained to 32 weeks. For the toddler trial, differences in secondary outcomes favouring smalltalk plus were evident at 12 weeks and maintained to 32 weeks. These trials provide some evidence of the benefits of a parenting intervention focused on the home learning environment for parents of toddlers but not infants. TRIAL REGISTRATION: 8 September 2011; ACTRN12611000965909 .This research was commissioned and funded by the Victorian Government Department of Education and Early Childhood Development (DEECD), and designed and conducted at the Parenting Research Centre. NH, EW, SB, AS, MT, MY and JN were employees of the Parenting Research Centre when this study was conducted. EW was part-funded by the Centre for Research Excellence in Child Language at Murdoch Childrens Research Institute (NHMRC grant 1023493). NH, EW, SB and JN are funded by the Australian Communities Foundation (Coronella sub-fund) at La Trobe University. OU is supported by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula at the Royal Devon and Exeter NHS Foundation Trust. Views expressed are those of the authors and not necessarily those of DEECD, NIHR, NHS or the Department of Health
Rehabilitation of face-processing skills in an adolescent with prosopagnosia: Evaluation of an online perceptual training programme
In this paper we describe the case of EM: a female adolescent who acquired prosopagnosia following encephalitis at the age of eight. Initial neuropsychological and eye-movement investigations indicated that EM had profound difficulties in face perception as well as face recognition. EM underwent 14 weeks of perceptual training in an online programme that attempted to improve her ability to make fine-grained discriminations between faces. Following training, EM’s face perception skills had improved, and the effect generalized to untrained faces. Eye-movement analyses also indicated that EM spent more time viewing the inner facial features post-training. Examination of EM’s face recognition skills revealed an improvement in her recognition of personally-known faces when presented in a laboratory-based test, although the same gains were not noted in her everyday experiences with these faces. In addition, EM did not improve on a test assessing the recognition of newly encoded faces. One month after training, EM had maintained the improvement on the eye-tracking test, and to a lesser extent, her performance on the familiar faces test. This pattern of findings is interpreted as promising evidence that the programme can improve face perception skills, and with some adjustments, may at least partially improve face recognition skills
Recent radio talks
Recent Rural Radio Talks
Dairy Hygiene is Important; - D.C. Mickle
Farm Water Supplies; - K. Needham
Handling the Apple Crop; - K. Whitely
Renovation of Irrigated Pastures; - Dairying division
More About Lupinosis; - H. W. Bennetts
Progress in Doublegee Control; - Norman Halse
Changing Practices in Tobacco Growing in W.A.; - G. A. Pearce
Progress in doublegee control; - G.A. Pearce
Some Uses of Radio Isotopes in Agriculture; - E. N. Fitzpatrick
Guildford Grass—Sign of a Run-Down Pasture; - R. A. Bettenay
Silage and when to feed it; - R. Bettenay
Ants in the Apiary; - R. S. Coleman
Bacterial Canker of Stone Fruits; - Olga M. Goss
Poison Plants in the Home Garden; - R. D. Royce
The Cabbage White Butterfly; - C. F. H. Jenkins
Summer Treatments for San Jose Scale; - C. F. H. Jenkins
Preparations for Fodder Conservation; - H.G. Cariss
Sudan Grass Survived Dry Summer; - R.A. Bettenay
Root Maggot Flies; - J. A. Button
Fallowing for Cropping; - A.S. Wild
Feeding for Milk Quality; - L. C. Snook
The Rabbit— Friend or Foe. A. R. Tomlinso
Living environment, heating-cooling behaviours and well-being: Survey of older South Australians
At a time when the population is ageing and most people choose to live in their own home for as long as possible, it is important to consider various aspects of supportive and comfortable environments for housing. This study, conducted in South Australia, aims to provide information about the links between the type of housing in which older people live, the weather and occupants’ heating and cooling behaviours as well as their health and wellbeing. The study used a Computer-Assisted Telephone Interviewing (CATI) system to survey 250 people aged 65 years and over who lived in their own home. The respondents were recruited from three regions representing the three climate zones in South Australia: semi-arid, warm temperate and temperate. The results show that while the majority of respondents reported being in good health, many lived in dwellings with minimal shading and no wall insulation and appeared to rely on the use of heaters and coolers to achieve thermally comfortable conditions. Concerns over the cost of heating and cooling were shared among the majority of respondents and particularly among people with low incomes. Findings from this study highlight the importance of providing information to older people, carers, designers and policy makers about the interrelationships between weather, housing design, heating and cooling behaviours, thermal comfort, energy use and health and well-being, in order to support older people to age in place independently and healthily.Veronica Soebarto, Helen Bennetts, Alana Hansen, Jian Zuo, Terence Williamson, Dino Pisaniello, Joost van Hoof, Renuka Visvanatha
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