1,722,262 research outputs found
Solutions for certain classes of the Riccati differential equation
No full textWe derive some analytic closed-form solutions for a class of Riccati equations y'(x) - lambda(0)(x) y(x) +/- y(2)(x) = +/- s(0)(x) where lambda(0)( x), s(0)( x) are C-infinity- functions. We show that if delta(n) = lambda(n)s(n-1) - lambda(n-1)s(n) = 0, where lambda(n) = lambda(')(n-1) + s(n-1) + lambda(0)lambda(n-1) and s(n) = s(n-1)(')+ s(0)lambda(k-1) , n = 1, 2, ... , then the Riccati equation has a solution given by y( x) = -/+ s(n-1)(x)/ lambda(n-1)(x). Extension to the generalized Riccati equation y'(x) + P(x) y(x) + Q(x) y(2)(x) = R(x) is also investigated
The potential of the fungus, Verticillium Lecanii as a control agent of glasshouse aphid pests
No full textThe ecology of the fungus, Vertlciilium lecanii, and its potential as a microbiological insect cide against the aphids, MyzuS persicae, Macrosiphoniella sanborni and Brachycaudus helichrysz, on glasshouse chrysanthemums have been examined.To achieve reproducibility, a single-spore isolate of V. lecanii, C-3, was used and designated as standard. It produced conidiospores on solid media and, more abundantly and readily, blastospores in liquid media. In nutritional studies, submerged production of conidiospores was not achieved. In aqueous suspension, conidiospores survived longer than blastospores. Conidiospores exposed below 80% relative humidity soon died, the speed of death depending on the spore microenvironment.A bioassay technique was developed and is believed to be the first statistically reliable method of quantifying fungal spore pathogenicity towards insects. With M. sanborni.the semi-weighted mean lethal concentration 50% of 28 assays was 1.83 x 10"' spore /ml suspension (fiducial limits, 1.45 and 2.31). All but one of 15 V„ lecanii strains, some pathogens of other insects and some probable hynerparasxtes of rust fungi, were similar in pathogenicity to C-3, Five other strains, all from rust or mildew fungi, were apathogenxc. B ..astospores of C—3 were approximately twice as pathogenic as conidiosporeso With single- and multi-spore isolates, repeated passage through apaids or subcu, ture on agars scarcely altered pathogenicity, but subculture greatly chanced colonial morphology.In glasshouses, blastospores and conidiospores produced similar levels of aphid control. Spore sprays established excellent control of My. persicae within 2-3 weeks, maintaining control for up to 8 weeks. Also, B. helichrysi was controlled in vegetative plant tips but not on tightly closed flower buds. Control of M. sanborni was usually unsatisfactory. In laboratory bioassays, all 3 aphid species were equally susceptible to V. lecariii suggesting that behavioural and ecological factors explain differences in glasshouses. V. lecanii could be used advantageously in integrated control systems on chrysanthemums.<br/
Hall (Richard) : Stanley. An adventurer explored
No full textChrétien Jean-Pierre. Hall (Richard) : Stanley. An adventurer explored. In: Revue française d'histoire d'outre-mer, tome 65, n°240, 3e trimestre 1978. p. 448
Hall (Richard) : Stanley. An adventurer explored
No full textChrétien Jean-Pierre. Hall (Richard) : Stanley. An adventurer explored. In: Revue française d'histoire d'outre-mer, tome 65, n°240, 3e trimestre 1978. p. 448
Hall, Richard H. 1968: Professionalization and Bureaucratization.
No full textSchwarting R. Hall, Richard H. 1968: Professionalization and Bureaucratization. In: Kühl S, ed. Schlüsselwerke der Organisationsforschung. Wiesbaden: VS Verlag für Sozialwissenschaften; 2015: 324-328
Hall, Richard J, WX5262
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/389834Surname: HALL. Given Name(s) or Initials: RICHARD J. Military Service Number or Last Known Location: WX5262. Missing, Wounded and Prisoner of War Enquiry Card Index Number: 42747.214405
Item: [2016.0049.22127] "Hall, Richard J, WX5262
The development of accident predictive models for junctions
No full textSIGLEAvailable from British Library Document Supply Centre- DSC:DX92277 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Unidentified man, Warner Hall, Richard C. Foster, Hayes Tucker, and Hill Ferguson sitting on stage
No full textAn unidentified man, Warner Hall, Richard C. Foster, Hayes Tucker, and Hill Ferguson are sitting on a stage around 1940
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