1,194 research outputs found

    Substorms on Mercury?

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    Qualitative similarities between some of the variations in the Mercury encounter data and variations in the corresponding regions of the earth's magnetosphere during substorms are pointed out. The Mariner 10 data on Mercury show a strong interaction between the solar wind and the plant similar to a scaled down version of that for the earth's magnetosphere. Some of the features observed in the night side Mercury magnetosphere suggest time dependent processes occurring there

    State-trace analysis: dissociable processes in a connectionist network?

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    Some argue the common practice of inferring multiple processes or systems from a dissociation is flawed (Dunn, 2003). One proposed solution is state-trace analysis (Bamber, 1979), which involves plotting, across two or more conditions of interest, performance measured by either two dependent variables, or two conditions of the same dependent measure. The resulting analysis is considered to provide evidence that either (a) a single process underlies performance (one function is produced) or (b) there is evidence for more than one process (more than one function is produced). This article reports simulations using the simple recurrent network (SRN; Elman, 1990) in which changes to the learning rate produced state-trace plots with multiple functions. We also report simulations using a single-layer error-correcting network that generate plots with a single function. We argue that the presence of different functions on a state-trace plot does not necessarily support a dual-system account, at least as typically defined (e.g. two separate autonomous systems competing to control responding); it can also indicate variation in a single parameter within theories generally considered to be single-system accounts

    Pre-bit hackamore training (1993)

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    Hackamores are used to start colts in training. An untrained colt makes many mistakes, and the trainer needs to correct them. This publication gives instructions on how to use a hackamore

    The DCU laser ion source

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    Laser ion sources are used to generate and deliver highly charged ions of various masses and energies. We present details on the design and basic parameters of the DCU laser ion source (LIS). The theoretical aspects of a high voltage (HV) linear LIS are presented and the main issues surrounding laser-plasma formation, ion extraction and modeling of beam transport in relation to the operation of a LIS are detailed. A range of laser power densities (I ∼ 108–1011 W cm−2) and fluences (F = 0.1–3.9 kJ cm−2) from a Q-switched ruby laser (full-width half-maximum pulse duration ∼ 35 ns, λ = 694 nm) were used to generate a copper plasma. In “basic operating mode,” laser generated plasma ions are electrostatically accelerated using a dc HV bias (5–18 kV). A traditional einzel electrostatic lens system is utilized to transport and collimate the extracted ion beam for detection via a Faraday cup. Peak currents of up to I ∼ 600 μA for Cu+ to Cu3+ ions were recorded. The maximum collected charge reached 94 pC (Cu2+). Hydrodynamic simulations and ion probe diagnostics were used to study the plasma plume within the extraction gap. The system measured performance and electrodynamic simulations indicated that the use of a short field-free (L = 48 mm) region results in rapid expansion of the injected ion beam in the drift tube. This severely limits the efficiency of the electrostatic lens system and consequently the sources performance. Simulations of ion beam dynamics in a “continuous einzel array” were performed and experimentally verified to counter the strong space-charge force present in the ion beam which results from plasma extraction close to the target surface. Ion beam acceleration and injection thus occur at “high pressure.” In “enhanced operating mode,” peak currents of 3.26 mA (Cu2+) were recorded. The collected currents of more highly charged ions (Cu4+–Cu6+) increased considerably in this mode of operation

    Local ciliate communities associated with aquatic macrophytes

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    This study, based within the catchment area of the River Frome, an important chalk stream in the south of England, compared ciliated protozoan communities associated with three species of aquatic macrophyte common to lotic habitats: Ranunculus penicillatus subsp. pseudofluitans, Nasturtium officinale and Sparganium emersum. A total of 77 ciliate species were counted. No species-specific ciliate assemblage was found to be typical of any one plant species. Ciliate abundance between plant species was determined to be significantly different. The ciliate communities from each plant species were unique in that the number of species increased with ciliate abundance. The community associated with R. penicillatus subsp. pseudofluitans showed the highest consistency and species richness whereas S. emersum ciliate communities were unstable. Most notably, N. officinale was associated with low ciliate abundances and an apparent reduction in biofilm formation, discussed herein in relation to the plant’s production of the microbial toxin phenethyl isothiocyanate. We propose that the results reflect differences in the quantity and quality of biofilm present on the plants, which could be determined by the different plant morphologies, patterns of plant decay and herbivore defense systems, all of which suppress or promote the various conditions for biofilm growth. [Int Microbiol 2014; 17(1):31-40]Keywords: Ranunculus · Nasturtium · toxin phenethyl isothiocyanate (PEITC) · biofilms · macrophytes · ciliates · microbial biodiversit

    Sulphur nutrition of pastures and crops Phosphorus and potassium nutrition of pastures on deep sands in the high rainfall areas

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    CONTENTS A. SULPHUR 1. Sources, rates, time of application of sulphur to legume pastures (high rainfall) - 80AL1, 80AL4, 80MA1, 80KE1. 2. Sulphur soil test on pastures (high rainfall) - 80AL12, 80AL13, 80AL14, 80BY2, 80KE2. 3. Sulphur rundown on sulphur absorbing soils of the high rainfall areas - 80BY1. 4. Sulphur requirements of pasture in low rainfall areas - 80JE17, 80M020. 5. Residual value of 1979 applied sulphur. Rates of fine gypsum applied 1980 - 79AL2, 79AL18, 79AL22, 79AL23, 79AL25, 79AL41, 78BA8 B, 79BY3, 79BY4, 79HA2, 79KE3, 79KE7, 79M020. 6. Sulphur requirements of wheat - 80JE16, 80M09. B. PHOSPHORUS 7. Sources, rates, time of application of phosphorus to legume pastures - 80AL2, 80AL5, 80AL15, 80MA2. C. POTASSIUM 8. Sources, rates, time of application of potassium to legume pastures - 80AL3, 80AL6, 80MA3. D. SLOW RELEASE P,S,K FERTILIZERS - 1979 TRIALS 9. Phosphorus sulphur and potassium slow release fertilizers on pastures 1980 results - 79AL1, 79KE2, 79MA2. E. APPENDIX P.R.D./Albany Regional Office PKS collaborative trials, sulphur results. (sulphur soil test on pastures) - 80AL44, 80AL46, 80AL47, 80AL72

    Sulphur nutrition of pastures and crops, Phosphorus and potassium nutrition of high rainfall pastures on deep sands, Soil acidity - high rainfall pastures

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    A. SULPHUR - HIGH RAINFALL 1. Rates and time of application of superphosphate to pastures. 79AK2, 79AL23, 79AL25, 79AL41, 81BY1, 81KE1. 2. Sulphur soil test calibration on pastures. 79AL18, 80BY2, 80KE2. 3. Sulphur soil test calibration on pastures: Co-operative PKS soil test project on pastures on duplex soils of the east Albany area (PRD/ARO). Sulphur results. 80 AL44, 46, 47, 48, 72, 73 81AL51, 53, 55 4. Sulphur on adsorbing soils receiving no current S input. 80BY1., 80AL16. 5. Sources, rates, time of application of sulphur on pastures. 80AL1, 80AL4, 81AL3, 81AL4, 80KE1, 80MA1 B. SULPHUR - LOW RAINFALL 1. Sulphur on pastures. 80JE17, 80M020. 2. Sulphur on cereals 80JE16, 80M09. C. PHOSPHORUS 1. Sources, rates time of application of phosphorus on high rainfall pastures on deep sands. 79AL1, 80AL2, 80AL5, 80AL15, 81AL5, 81AL6, 81KE2, 79MA2, 80MA2, 81MA4. D. POTASSIUM 1. Sources, rates, time of application of potassium on high rainfall pastures on deep sand. 80AL3, 80AL6, 81AL7, 81AL8, 81MA3. E. SOIL ACIDITY 1. High rainfall soil pH survey - 2. Lime on old lan·d pastures (high 81AL10, 81ALll, 81AL12, 81AL13, Albany Region - Summary rainfall) 81AL14, 81AL15, 81AL16 3. Topdressed vs incorporated lime on new land acid peat. 81AL9 4. Lime on new land pastures: 1981 results from 1979-80 commenced trials by Albany Regional Office staff. 79AL14, 79AL16, 80AL50, 80AL51, 80AL52, 80AL53, 80AL54

    Sulphur nutrition of pastures. Potassium nutrition of high rainfall pastures on deep sands

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    A. Sulphur - High Rainfall – 80AL1, 80AL4 (1980), 80AL4 B (established 1983). Sulphur rundown on heavy soils - 80BY1. Sources, rates, time of application of sulphur to pastures - 80AL1, 80AL4, 80AL4B. Sources, rates, time of application of sulphur to legume pastures – 80AL1, 80AL4, 80AL4B. Sulphur nutrition of pastures. 83PE36. B. Sulphur - Low Rainfall – 82AL9, 80JE16/17 82KA4. Sulphur on pastures - 80JE16/17, 82AL9, 82KA4. Sulphur on absorbing soils receiving no current S input – 80BY1. C. Potassium. Sources, rates, time of application of potassium on high rainfall deep sand pastures - 80AL3, 80AL6
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