1,107 research outputs found

    Pasture Manipulaton on animal, crop and pasture production

    Get PDF
    1. Effect of Pasture Manipulation on Animal Production - 81M01 - \u27Ranfurly\u27. 2. Effect of Pasture Manipulation on Crop Production - 81M01 - \u27Ranfurly\u27. 3. Effect of Pasture Manipulation on Animal Production - 82NA29 - \u27Culford\u27. 4. Pasture Manipulation in a 1:1 Rotation at Esperance - 79El5 – \u27Esperance Downs\u27. 5. Pasture Manipulation in a 2 pasture: 1 crop Rotation – 81E35 – \u27Esperance Downs\u27. 6. Pasture Manipulation - Effects on Take-all - 82LG25 - \u27McMahons\u27

    Long term pasture manipulation trials

    Get PDF
    A.W.I.R.C Project 498/0029 Pasture manipulation on the Esperance sandplain. Introduction In 1981 a 2 pasture: 1 crop rotation trial incorporating four pasture manipulation treatments was commenced on the Esperance Sandplain to determine: 1. the effect of herbicide manipulation of pasture composition on pasture and animal production. 2. the effect of grass control on take-all levels in a following cereal crop. 3. the effect of grass control on desicantha weevil levels in a following cereal crop. Rotation trial for wheat comparing a pure clover ley with a mixed pasture ley on the Esperance sandplain - Esperance Down Research Station. The effect of chemical grass control in pastures on subsequent crop production and take-all levels - 82LG25

    A Study of Compact Radio Sources in Nearby Face-on Spiral Galaxies. II. Multiwavelength Analyses of Sources in M51

    Get PDF
    We report the analysis of deep radio observations of the interacting galaxy system M51 from the Very Large Array, with the goal of understanding the nature of the population of compact radio sources in nearby spiral galaxies. We detect 107 compact radio sources, 64% of which have optical counterparts in a deep Hα\alpha Hubble Space Telescope image. Thirteen of the radio sources have X-ray counterparts from a {\em Chandra} observation of M51. We find that six of the associated Hα\alpha sources are young supernova remnants with resolved shells. Most of the SNRs exhibit steep radio continuum spectral indices onsistent with synchrotron emission. We detect emission from the Type Ic SN 1994I nearly a decade after explosion: the emission (160±22μ160\pm22 \muJy beam−1^{-1} at 20 cm, 46±11μ46\pm11 \muJy beam−1^{-1} at 6cm, α=−1.02±0.28\alpha=-1.02\pm0.28) is consistent with light curve models for Type Ib/Ic supernovae. We detect X-ray emission from the supernova, however no optical counterpart is present. We report on the analysis of the Seyfert 2 nucleus in this galaxy, including the evidence for bipolar outflows from the central black hole.Comment: 22 pages, 8 figures (5 color) in separate files, AASTeX. Full resolution figures and preprint may be obtained by contacting [email protected]. AJ accepte

    23 GHz VLBI Observations of SN 2008ax

    Get PDF
    We report on phase-referenced 23 GHz Very-Long-Baseline-Interferometry (VLBI) observations of the type IIb supernova SN 2008ax, made with the Very Long Baseline Array (VLBA) on 2 April 2008 (33 days after explosion). These observations resulted in a marginal detection of the supernova. The total flux density recovered from our VLBI image is 0.8±\pm0.3 mJy (one standard deviation). As it appears, the structure may be interpreted as either a core-jet or a double source. However, the supernova structure could be somewhat confused with a possible close by noise peak. In such a case, the recovered flux density would decrease to 0.48±\pm0.12 mJy, compatible with the flux densities measured with the VLA at epochs close in time to our VLBI observations. The lowest average expansion velocities derived from our observations are (1.90±0.30)×105(1.90 \pm 0.30) \times 10^5 km s−1^{-1} (case of a double source) and (5.2±1.3)×104(5.2 \pm 1.3) \times 10^4 km s−1^{-1} (taking the weaker source component as a spurious, close by, noise peak, which is the more likely interpretation). These velocities are 7.3 and 2 times higher, respectively, than the maximum ejecta velocity inferred from optical-line observations.Comment: 4 pages, 3 figures. Accepted in A&A on 24/03/200

    The Insect Situation in 1968

    Get PDF
    What happened last year will have some influence on insect conditions in 1968. The authors provice some suggestions on what to look for, and how to handle both crop and livestock insect problems

    Insect and Rodent Prospects for 1962

    Get PDF
    What insects will we have this year? Insect problems depend a lot on weather conditions. Keeping this in mind and looking at the problems in 1961, here are the prospects for 1962 - and what to do about them

    Insect Control in 1967

    Get PDF
    Advances in chemical control and farming procedures will let you win the battle agaisnt the bugs, but many questions concerning these measures need to be answered for you

    Relationships Between the Nutrient Content of Irrigated Pasture on Offer and that Selected by Grazing Dairy Cows

    Get PDF
    An experiment was conducted to determine the dry matter, energy, crude protein and fibre intake by dairy cows in late lactation when grazing perennial pasture offered at allocations of 15, 20, 30 and 40 kg DM/cow.day. The cows consistently selected a diet 10% higher in digestibility than that on offer. In contrast, cows selected diets with crude protein levels increasing from 22% to 40%, above that in pasture on offer, as pasture allocation increased. A similar pattern was observed for the intake of white clover (Trifolium repens L). The increase in the concentration of crude protein in the diet (as allocation increased) was due to the consumption of white clover and a decrease in the consumption of the dead components of the sward. On the other hand, the neutral detergent fibre content of the diet selected was lower than that on offer, and declined as pasture allocation increased

    Plant and Sward Characteristics to Achieve High Intake in Ruminants

    Get PDF
    Key points Intake is affected by complex interactions between signals from the digestive tract, intermediary metabolism and energy supply, and behavioural signals associated with learned behaviours or sensory signals. The ideal sward needs to have characteristics that are similar to total mixed rations to achieve high intake and animal performance. Genetic manipulation of plants may offer an accelerated rate of plant improvement, but benefits need to be demonstrated in a systems context

    A Radio and X-Ray Study of Historical Supernovae in M83

    Full text link
    We report the results of 15 years of radio observations of the six historical supernovae (SNe) in M83 using the Very Large Array. We note the near linear decline in radio emission from SN 1957D, a type II SN, which remains a non-thermal radio emitter. The measured flux densities from SNe 1923A and 1950B have flattened as they begin to fade below detectable limits, also type II SNe. The luminosities for these three SNe are comparable with the radio luminosities of other decades-old SNe at similar epochs. SNe 1945B, 1968L, and 1983N were not detected in the most recent observations and these non-detections are consistent with previous studies. We report the X-ray non-detections of all six historical SNe using the Chandra X-ray Observatory, consistent with previous X-ray searches of other decades-old SNe, and low inferred mass loss rates of the progenitors.Comment: 3 color ps figure
    • …
    corecore