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  • 1
    Electronic Resource
    Electronic Resource
    Propulsion efficiency and cost of transport for copepods: a hydromechanical model of crustacean swimming (1985)
    Springer
    Marine biology 86 (1985), S. 283-295 
    Details
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the absence of direct measurement, costs of locomotion to small swimming Crustacea (〈10 mm) have been derived exclusively through application of the fluid dynamic theory. Results indicate very low swimming costs, and contradict experimental data on larger Crustacea (15 to 100 mm) that suggest a three-fold increase in metabolic rate with increasing swimming speed. This paper introduces a swimming model that analyzes the hydrodynamic forces acting on a crustacean swimming at non-steady velocity. The model treats separately the hydrodynamic forces acting on the body and the swimming appendages, approximating the simultaneous solution of equations quantifying the drag and added-mass forces on each by stepwise integration. Input to the model is a time-series of instantaneous swimming-appendage velocities. The model output predicts a corresponding time-series of body velocities as well as the mechanical energy required to move the swimming appendages, dissipated kinetic energy, and metabolic cost of swimming. Swimming of the calanoid copepod Pleuromamma xiphias (Calanoida) was analyzed by extrapolating model parameters from data available in the literature. The model predictions agree well with empirical observations reported for larger crustaceans, in that swimming for copepods is relatively costly. The ratio of active to standard metabolism for P. xiphias was 〉3. Net cost of transport was intermediate to the values found experimentally for fish and larger crustaceans. This was a consequence of the predicted mechanical efficiency (34%) of the copepod's paddle propulsion, and of increased parasitic resistance resulting from non-steady velocity swimming.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00397515
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  • 2
    Electronic Resource
    Electronic Resource
    Biology of the Acacia gall rust, Uromycladium tepperianum (1987)
    Oxford, UK : Blackwell Publishing Ltd
    Plant pathology 36 (1987), S. 0 
    Details
    ISSN: 1365-3059
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Germinating teliospores of Uromycladium tepperianum formed penetration pegs, which directly penetrated host epidermal cells, on the tip cell of three-celled germ tubes. Diploid nuclei within teliospores appeared to divide soon after germination commenced. Only one of the daughter nuclei moved out of the teliospores with the developing germ tubes. Reactions of seedlings inoculated with teliospores from different host species and differences in teliospore dimensions indicated that distinct genotypes of U. tepperianum adapted to particular host species occur in Australia. Limited hyphal growth occurred in two of 20 African Acacia spp. inoculated with teliospores from Acacia saligna. Fungal development was, however, restricted by necrosis of surrounding host cells. U. tepperianum appears to be suitably host-specific for use as a biological control agent against Ac. saligna, a weed in South Africa.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-3059.1987.tb02183.x
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  • 3
    Electronic Resource
    Electronic Resource
    A method for controlling Hakea sericea Schrad. seedlings using the fungus Colletotrichum gloeosporioides (Penz.) Sacc (1989)
    Oxford, UK : Blackwell Publishing Ltd
    Weed research 29 (1989), S. 0 
    Details
    ISSN: 1365-3180
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary. The shrub Hakea sericea Schrad. is a major weed in the southern and south-western Cape Province of South Africa. A dried formulation on wheat bran of the fungus Colletotrichum gloeosporioides (Penz.) Sacc. was sprinkled onto plots of young H. sericea seedlings at three sites in the southwestern Cape Province. Following periods of rain, the fungus sporulated profusely on the bran and rain-splash dispersal of conidia from the bran resulted in infection of seedlings which consequently died back from the stem tips. Applications of bran inoculum during early winter when seedlings were in the cotyledonary to 20-leaf stage were more effective (93–98% mortality) than later applications (30–36% mortality).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-3180.1989.tb01317.x
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  • 4
    Electronic Resource
    Electronic Resource
    Stimulus-Evoked Changes in Extracellular Calcium in Optic Tectum of the Goldfish: Possible Role in Neuroplasticity (1986)
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 481 (1986), S. 0 
    Details
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-6632.1986.tb27169.x
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  • 5
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    Providing Business Information to Production Workers: Correlates of Compensation and Profitability (1988)
    Ithaca, N.Y. : Periodicals Archive Online (PAO)
    Industrial and Labor Relations Review. 41:4 (1988:July) 605 
    Details
    ISSN: 0019-7939
    Topics: Economics
    URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pao:&rft_dat=xri:pao:article:3121-1988-041-04-000009
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  • 6
    Electronic Resource
    Electronic Resource
    Structure of {4,4'-[iminobis(1,3-propanediylnitrilo)]-di-2-pentanonato-N,N',N'',O,O'}copper (1987)
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 43 (1987), S. 2056-2058 
    Details
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0108270187089017
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  • 7
    Electronic Resource
    Electronic Resource
    Linkage disequilibrium and gametophytic self-incompatibility (1986)
    Springer
    Theoretical and applied genetics 73 (1986), S. 102-112 
    Details
    ISSN: 1432-2242
    Keywords: Linkage ; Linkage disequilibrium ; Gametophytic self-incompatibility ; Sheltering of lethals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The approach to linkage equilibrium of a locus linked to the locus determining gametophytic self-incompatibility (S) is considered. For the simplest case of three alleles at the S locus and two at the linked locus it is necessary to consider 3 measures of linkage disequilibrium. These are found to approach their equilibrium value of zero in one of three ways: 1) steadily declining to zero; 2) oscillating as decline proceeds; 3) a combination: 2) followed by 1). Linkage equilibrium may be established before genotype frequencies reach their expectation under random crossing. Earlier studies (Li 1951; Moran 1962) of the approach to S allele equilibrium have been based on the assumption that all types of pollen take part in fertilizations equally frequently. Such an assumption leads to simpler expressions for changes in S gene frequencies but is extremely unrealistic and, in particular, leads to a different rate of approach to equilibrium from the more comprehensive model. It is shown that even in the absence of selection it is not possible to predict the equilibrium gene frequency of a linked locus until S allele equilibrium is reached. This frequency may be either higher or lower than that calculated from a gene count in the starting genotype pool. However, these two gene frequencies may stabilize long before linkage equilibrium is achieved. An examination of selection against one genotype at the linked locus is undertaken. If linkage is complete, lethality can be less effective at reducing the gene frequency than is less intense selection (in only a few generations of selection). Here too linkage equilibrium may be established with selection still effective in bringing about a decline in gene frequency. An examination of the analysis and conclusions of Rasmuson (1980) shows that because these were based on the inadequate formulae previously discussed and exclude phenomena discussed above, they are misleading. The possibility of a gametophytic self-incompatibility system providing a sufficient condition for the sheltering of lethals in the absence of the condition of complete linkage to the S locus (r=0) is shown to be unlikely.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00273726
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  • 8
    Electronic Resource
    Electronic Resource
    The reactive chemisorption of carbon dioxide at magnesium and copper surfaces at low temperature (1988)
    Springer
    Catalysis letters 1 (1988), S. 11-19 
    Details
    ISSN: 1572-879X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract X-ray photoelectron spectroscopic studies reveal that the following species are present when carbon dioxides reactively chemisorbed at magnesium and copper surfaces: CO2(phys) CO3(a), CO 2 − (a) CO(a) and C(a). At Mg(0001) surfaces, it has been shown that there is a step-wise process, with a whole range of metastable species formed above 80 K. By contrast, at copper surfaces the chemistry is less complex, the most significant species being CO 2 − (a); these form preferentially under conditions which favour high surface concentrations of CO2(a) and therefore co-operative effects within the adlayer. The need to develop experimental methods for studying surface processes at high pressures is well recognised, however the present work shows that for some systems low temperatures (and pressures) offer a possible alternative strategy for delineating the step-wise nature of the reaction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00765348
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  • 9
    Electronic Resource
    Electronic Resource
    Crystallization embrittlement of Ni-Ti-B glasses (1988)
    Springer
    Journal of materials science 23 (1988), S. 3519-3527 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract While metallic glasses have excellent toughness and ductility in the as-cast and unrelaxed state, the process of crystallization leads to a nearly continuous and significant embrittlement. This change is examined on three Ni-Ti-B glasses and related to the morphology and distribution of the crystals obtained. For the partially crystallized materials, failure still occurs after intense shear on one well-defined shear plane, and it is shown how the crystals act as stress and strain incompatibilities causing localized crack or cavity formation. The relationships between sample mechanical properties, fracture surface characteristics and crystal distributions allow an analysis of cavity nucleation and growth rates, and thereby make it possible to suggest microstructures which may maintain reasonable toughness.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00540490
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  • 10
    Electronic Resource
    Electronic Resource
    Post-compaction heat-treatment response of dynamically-compacted Inconel 718 powder (1987)
    Springer
    Journal of materials science 22 (1987), S. 1509-1516 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Dynamically-compacted Inconel 718 powder has been heat treated in order to examine the evolution of microstructural recovery and hardness, recrystallization and grain coarsening, and interparticle-adhesion and fracture response. Following dynamic compaction the compacted powders are imperfectly bonded and the material is fairly brittle; the shock wave has caused significant hardening; local microstructures and properties are variable from particle surface to interior. Following annealing at 900 to 1000° C, virtually complete recrystallization occurs giving rise to a material which is softened and has a fine-scale microstructure. Little improvement in fracture response occurs, however, because the oxidized prior-particle surfaces do not weld together. Shock-wave consolidation offers the possibility of producing monolithic, microstructurally-fine materials, providing suitable post-consolidation thermo-mechanical processes are developed to overcome the limited bonding problem.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01233155
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