606 research outputs found
Bullying Prevention Program: Possible Impact on Academic Performance
The research conducted sought to find the effect of the implementation of the Olweus Bullying Prevention Program on the academic performance of students in the third through eighth grade. The study examined the relationship between the implementation of the Olweus Bullying Prevention Program and the change in academic performance, as measured by the Measures of Academic Progress (MAP) assessment. The post-test scores of third through fifth grade students from one elementary school which had implemented the prevention program were compared with the post-test scores for the same grade levels at an elementary school that had not implemented a bullying prevention program. The same comparison was made between a middle school that had implemented the Olweus program and a middle school that had not implemented a prevention program. The surveys from the two schools that had implemented the Olweus program demonstrated that both of the schools had experienced a significant decrease in the intensity and frequency of reported bullying behavior at the conclusion of the first year of the program. The reduction was most significant in the elementary school. A one-way analysis of covariance (ANCOVA) was conducted and the difference in adjusted means of the post assessment scores between the control and experimental groups was found to be significant. For the students that had not been involved in the bullying prevention program, the adjusted mean score was 215.64, while those involved in the prevention program had an adjusted mean score of 217.01
A Kerr-microresonator optical clockwork
Kerr microresonators generate interesting and useful fundamental states of
electromagnetic radiation through nonlinear interactions of continuous-wave
(CW) laser light. Using photonic-integration techniques, functional devices
with low noise, small size, low-power consumption, scalable fabrication, and
heterogeneous combinations of photonics and electronics can be realized. Kerr
solitons, which stably circulate in a Kerr microresonator, have emerged as a
source of coherent, ultrafast pulse trains and ultra-broadband
optical-frequency combs. Using the f-2f technique, Kerr combs support
carrier-envelope-offset phase stabilization for optical synthesis and
metrology. In this paper, we introduce a Kerr-microresonator optical clockwork
based on optical-frequency division (OFD), which is a powerful technique to
transfer the fractional-frequency stability of an optical clock to a lower
frequency electronic clock signal. The clockwork presented here is based on a
silicon-nitride (SiN) microresonator that supports an optical-frequency
comb composed of soliton pulses at 1 THz repetition rate. By electro-optic
phase modulation of the entire SiN comb, we arbitrarily generate
additional CW modes between the SiN comb modes; operationally, this
reduces the pulse train repetition frequency and can be used to implement OFD
to the microwave domain. Our experiments characterize the residual frequency
noise of this Kerr-microresonator clockwork to one part in , which
opens the possibility of using Kerr combs with high performance optical clocks.
In addition, the photonic integration and 1 THz resolution of the SiN
frequency comb makes it appealing for broadband, low-resolution liquid-phase
absorption spectroscopy, which we demonstrate with near infrared measurements
of water, lipids, and organic solvents
An Integrated-Photonics Optical-Frequency Synthesizer
Integrated-photonics microchips now enable a range of advanced
functionalities for high-coherence applications such as data transmission,
highly optimized physical sensors, and harnessing quantum states, but with
cost, efficiency, and portability much beyond tabletop experiments. Through
high-volume semiconductor processing built around advanced materials there
exists an opportunity for integrated devices to impact applications cutting
across disciplines of basic science and technology. Here we show how to
synthesize the absolute frequency of a lightwave signal, using integrated
photonics to implement lasers, system interconnects, and nonlinear frequency
comb generation. The laser frequency output of our synthesizer is programmed by
a microwave clock across 4 THz near 1550 nm with 1 Hz resolution and
traceability to the SI second. This is accomplished with a heterogeneously
integrated III/V-Si tunable laser, which is guided by dual
dissipative-Kerr-soliton frequency combs fabricated on silicon chips. Through
out-of-loop measurements of the phase-coherent, microwave-to-optical link, we
verify that the fractional-frequency instability of the integrated photonics
synthesizer matches the reference-clock instability for a 1
second acquisition, and constrain any synthesis error to while
stepping the synthesizer across the telecommunication C band. Any application
of an optical frequency source would be enabled by the precision optical
synthesis presented here. Building on the ubiquitous capability in the
microwave domain, our results demonstrate a first path to synthesis with
integrated photonics, leveraging low-cost, low-power, and compact features that
will be critical for its widespread use.Comment: 10 pages, 6 figure
Architecture for the photonic integration of an optical atomic clock
Laboratory optical atomic clocks achieve remarkable accuracy (now counted to 18 digits or more), opening possibilities to explore fundamental physics and enable new measurements. However, their size and use of bulk components prevent them from being more widely adopted in applications that require precision timing. By leveraging silicon-chip photonics for integration and to reduce component size and complexity, we demonstrate a compact optical-clock architecture. Here a semiconductor laser is stabilized to an optical transition in a microfabricated rubidium vapor cell, and a pair of interlocked Kerr-microresonator frequency combs provide fully coherent optical division of the clock laser to generate an electronic 22 GHz clock signal with a fractional frequency instability of one part in 10^(13). These results demonstrate key concepts of how to use silicon-chip devices in future portable and ultraprecise optical clocks
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Terahertz-Rate Kerr-Microresonator Optical Clockwork
Kerr microresonators generate interesting and useful fundamental states of electromagnetic radiation through nonlinear interactions of continuous-wave (CW) laser light. With photonic-integration techniques, functional devices with low noise, small size, low-power consumption, scalable fabrication, and heterogeneous combinations of photonics and electronics can be realized. Kerr solitons, which stably circulate in a Kerr microresonator, have emerged as a source of coherent, ultrafast pulse trains and ultra-broadband optical-frequency combs. Using the f−2f technique, Kerr combs can support carrier-envelope-offset phase stabilization to enable optical synthesis and metrology. Here, we introduce a Kerr-microresonator optical clockwork, which is a foundational device that distributes optical-clock signals to the mode-difference frequency of a comb. Our clockwork is based on a silicon-nitride (Si3N4) microresonator that generates a Kerr-soliton frequency comb with a repetition frequency of 1 THz. We measure our terahertz clockwork by electro-optic modulation with a microwave signal, enabling optical-based timing experiments in this wideband and high-speed frequency range. Moreover, by EO phase modulation of our entire Kerr-soliton comb, we arbitrarily generate additional CW modes between the 1-THz modes to reduce the repetition frequency and increase the resolution of the comb. Our experiments characterize the absolute frequency noise of this Kerr-microresonator clockwork to one part in 1017, which is the highest accuracy and precision ever reported with this technology and opens the possibility of measuring high-performance optical clocks with Kerr combs.</p
Crop Updates 2006 - Cereals
This session covers twenty nine papers from different authors:
PLENARY
1. The 2005 wheat streak mosaic virus epidemic in New South Wales and the threat posed to the Western Australian wheat industry, Roger Jones and Nichole Burges, Department of Agriculture
SOUTH COAST AGRONOMY
2. South coast wheat variety trial results and best options for 2006, Mohammad Amjad, Ben Curtis and Wal Anderson, Department of Agriculture
3. Dual purpose winter wheats to improve productivity, Mohammad Amjad and Ben Curtis, Department of Agriculture
4. South coast large-scale premium wheat variety trials, Mohammad Amjad and Ben Curtis, Department of Agriculture
5. Optimal input packages for noodle wheat in Dalwallinu â Liebe practice for profit trial, Darren Chitty, Agritech Crop Research and Brianna Peake, Liebe Group
6. In-crop risk management using yield prophetÂź, Harm van Rees1, Cherie Reilly1, James Hunt1, Dean Holzworth2, Zvi Hochman2; 1Birchip Cropping Group, Victoria; 2CSIRO, Toowoomba, Qld
7. Yield ProphetÂź 2005 â On-line yield forecasting, James Hunt1, Harm van Rees1, Zvi Hochman2,Allan Peake2, Neal Dalgliesh2, Dean Holzworth2, Stephen van Rees1, Trudy McCann1 and Peter Carberry2; 1Birchip Cropping Group, Victoria; 2CSIRO, Toowoomba, Qld
8. Performance of oaten hay varieties in Western Australian environments, Raj Malik and Kellie Winfield, Department of Agriculture
9. Performance of dwarf potential milling varieties in Western Australian environments, Kellie Winfield and Raj Malik, Department of Agriculture
10. Agronomic responses of new wheat varieties in the Southern agricultural region of WA, Brenda Shackley and Judith Devenish, Department of Agriculture
11. Responses of new wheat varieties to management factors in the central agricultural region of Western Australia, Darshan Sharma, Steve Penny and Wal Anderson,Department of Agriculture
12. Sowing time on wheat yield, quality and $ - Northern agricultural region, Christine Zaicou-Kunesch, Department of Agriculture
NUTRITION
13.The most effective method of applying phosphorus, copper and zinc to no-till crops, Mike Bolland and Ross Brennan, Department of Agriculture
14. Uptake of K from the soil profile by wheat, Paul Damon and Zed Rengel, Faculty of Natural and Agricultural Sciences, University of Western Australia
15. Reducing nitrogen fertiliser risks, Jeremy Lemon, Department of Agriculture
16. Yield ProphetÂź and canopy management, Harm van Rees1, Zvi Hochman2, Perry Poulton2, Nick Poole3, Brooke Thompson4, James Hunt1; 1Birchip Cropping Group, Victoria; 2CSIRO, Toowoomba, Qld; 3Foundation for Arable Research, New Zealand; 4Cropfacts, Victoria
17. Producing profits with phosphorus, Stephen Loss, CSBP Ltd, WA
18. Potassium response in cereal cropping within the medium rainfall central wheatbelt, Jeff Russell1, Angie Roe2 and James Eyres2, Department of Agriculture1, Farm Focus Consultants, Northam2
19. Matching nitrogen supply to wheat demand in the high rainfall cropping zone, Narelle Simpson, Ron McTaggart, Wal Anderson, Lionel Martin and Dave Allen, Department of Agriculture
DISEASES
20. Comparative study of commercial wheat cultivars and differential lines (with known Pm resistance genes) to powdery mildew response, Hossein Golzar, Manisha Shankar and Robert Loughman, Department of Agriculture
21. On farm research to investigate fungicide applications to minimise leaf disease impacts in wheat â part II, Jeff Russell1, Angie Roe2and James Eyres2, Department of Agriculture1, and Farm Focus Consultants, Northam2
22. Disease resistance update for wheat varieties in WA, Manisha Shankar, John Majewski, Donna Foster, Hossein Golzar, Jamie Piotrowski, Nicole Harry and Rob Loughman, Department of Agriculture
23. Effect of time of stripe rust inoculum arrival on variety response in wheat, Manisha Shankar, John Majewski and Rob Loughman, Department of Agriculture
24. Fungicide seed dressing management of loose smut in Baudin barley, Geoff Thomas and Kith Jayasena, Department of Agriculture
PESTS
25. How to avoid insect contamination in cereal grain at harvest, Svetlana Micic, Paul Matson and Tony Dore, Department of Agriculture
ABIOTIC
26. Environment â is it as important as variety in sprouting tolerance? Thomas (Ben) Biddulph1, Dr Daryl Mares1, Dr Julie Plummer1 and Dr Tim Setter2, School of Plant Biology, University of Western Australia1 and Department of Agriculture2
27. Frost or fiction, Garren Knell, Steve Curtin and Wade Longmuir, ConsultAg Pty Ltd, WA
28. High moisture wheat harvesting in Esperance 2005, Nigel Metz, South East Premium Wheat Growers Association (SEPWA) Projects Coordinator, Esperance, WA
SOILS
28. Hardpan penetration ability of wheat roots, Tina Botwright Acuña and Len Wade, School of Plant Biology, University of Western Australia
MARKETS
29. Crop shaping to meet predicted market demands for wheat in the 21st Century, Cindy Mills and Peter Stone,Australian Wheat Board, Melbourn
Astrophysics with the Laser Interferometer Space Antenna
Laser Interferometer Space Antenna (LISA) will be a transformative experiment for gravitational wave astronomy as it will offer unique opportunities to address many key astrophysical questions in a completely novel way. The synergy with ground-based and other space-based instruments in the electromagnetic domain, by enabling multi-messenger observations, will add further to the discovery potential of LISA. The next decade is crucial to prepare the astrophysical community for LISA's first observations. This review outlines the extensive landscape of astrophysical theory, numerical simulations, and astronomical observations that are instrumental for modeling and interpreting the upcoming LISA datastream. To this aim, the current knowledge in three main source classes for LISA is reviewed: ultra-compact stellar-mass binaries, massive black hole binaries, and extreme or intermediate mass ratio inspirals. The relevant astrophysical processes and the established modeling techniques are summarized. Likewise, open issues and gaps in our understanding of these sources are highlighted, along with an indication of how LISA could help make progress in the different areas. New research avenues that LISA itself, or its joint exploitation with studies in the electromagnetic domain, will enable, are also illustrated. Improvements in modeling and analysis approaches, such as the combination of numerical simulations and modern data science techniques, are discussed. This review is intended to be a starting point for using LISA as a new discovery tool for understanding our Universe
Search for R-Parity Breaking Sneutrino Exchange at LEP
We report on a search for R--parity breaking effects due to supersymmetric tau--sneutrino exchange in the reactions e+e- to e+e- and e+e- to mu+mu- at centre--of--mass energies from 91~{\GeV} to 172~{\GeV}, using the L3 detector at LEP. No evidence for deviations from the Standard Model expectations of the measured cross sections and forward--backward asymmetries for these reactions is found. Upper limits for the couplings and for sneutrino masses up to m_{\SNT} \leq 190~\GeV are determined from an analysis of the expected effects due to tau sneutrino exchange
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