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121.
Terry A. Dick 《Ecology of Freshwater Fish》2011,20(4):646-655
Abstract – Stable δ13C and δ15N isotopes, diet and parasites demonstrated that the prey consumed by ninespine stickleback Pungitius pungitius in a small lake on Baffin Island changed during the summer and also revealed intraspecific variation in their ecological niche. In July, there were differences in the diets of male and female ninespine stickleback as indicated by the stable isotopes, differences corroborated by the data on diet composition and the parasite fauna. Differences suggested that the sexes occupied different habitats during spawning. During July, females utilise the shallower littoral areas consuming zooplankton and benthic organisms, while males occupy deeper areas of the littoral zone feeding mainly on pelagic zooplankton. Parasite data support these observations as males had higher infections of copepod‐transmitted parasites than females. There appeared to be no segregation of resources between males and females in late August, although the diet of both male and female ninespine stickleback shifted towards more benthic organisms, compared with July. Differences in δ13C isotope, diet composition and infections of co‐occurring parasites demonstrated that sympatric ninespine stickleback and Arctic char Salvelinus alpinus captured in the littoral zone occupied separate niches. Ninespine stickleback preyed mainly on zooplankton and chironomids, while Arctic char consumed a greater variety of prey items, including zooplankton and larger‐sized prey such as insects and ninespine stickleback. The multifaceted approach improved our understanding of the trophic ecology of ninespine stickleback in southern Baffin Island and quantified resource use and dietary overlap with Arctic char. 相似文献
122.
123.
Serum amyloid A (SAA) is an acute-phase protein in cats likely to be useful for diagnosing and monitoring inflammatory diseases,
especially if rapid, reliable and automated assays can be made available. A commercially available automated human SAA turbidimetric
immunoassay (SAA-TIA) was evaluated for determination of SAA in cats. Intra-assay and inter-assay imprecisions were in the
ranges 2.1–9.9% and 7.0–12.5%, respectively, and without significant inaccuracy. Eighty-eight cats were divided into groups
according to (A) the presence or absence of an acute-phase response (APR) (n = 23 and 65, respectively) and (B) clinical diagnosis (clinically healthy cats, cats diagnosed with inflammatory/infectious
diseases, endocrine/metabolic diseases, neoplastic diseases, and miscellaneous disorders (n=43, 13, 8, 4 and 20, respectively)). The observed SAA concentrations were, as expected, different for (A) cats with and without
an APR and (B) cats with inflammatory/infectious diseases compared to other diagnostic groups, except neoplastic diseases.
In conclusion, the SAA concentration in cats could be measured reliably using the commercially available TIA designed for
measuring human SAA, which should facilitate implementation of the parameter for routine diagnostic purposes.
Hansen, A.E., Schaap, M.K. and Kjelgaard-Hansen, M., 2006. Evaluation of a commercially available human serum amyloid A (SAA)
turbidimetric immunoassay for determination of feline SAA concentration. Veterinary Research Communications, 30(8), 863–872 相似文献
124.
To reduce S emissions, petroleum coke with a high concentration of S was combusted with limestone in a circulating fluidized bed (CFB) boiler. The combustion process creates a bed product that has potential for agricultural uses. This CFB product is often alkaline and enriched in S and other essential plant nutrients, but also contains high concentrations of Ni and V. Agricultural land application of CFB product is encouraged, but little information is available related to plant responses and environmental impacts. CFB product and agricultural lime (ag-lime) were applied at rates of 0, 0.5, 1.0, and 2.0 times the soil's lime requirement (LR) to an acidic soil (Wooster silt loam). The 2.0x LR application rate of CFB product was equivalent to 67.2 Mg ha(-1). Alfalfa yield was increased 4.6 times by CFB product and 3.8 times by ag-lime compared to untreated control. Application of CFB product increased the concentration of V in soil and alfalfa tissue, but not in soil water, and increased the concentration of Ni in soil and soil water, but not in alfalfa tissue. However, these concentrations did not reach levels that might cause environmental problems. 相似文献
125.
Anna J. M. Hopkins Margaret A. Dick Colleen A. Carlson Patricia E. Crane 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(4):537-548
Nectria flute canker is a disease of Pinus radiata stems caused by the pathogen Neonectria fuckeliana occurring in the southern parts of New Zealand. In Northern Hemisphere countries where N. fuckeliana is endemic, it is commonly found in Picea and Abies spp. Open wounds, dead attached branches and branch stubs have been identified as the primary infection courts. Although
in New Zealand the development of Nectria flute canker disease is associated with pruned branch stubs, recent studies suggest
that this is not the only possible entry method as the fungus has been found in trees prior to pruning. Three field trials
were established to examine the potential infection mechanisms for N. fuckeliana in P. radiata in New Zealand; including stem wounds and branch stubs. The difference between inoculations into the stem and into branch
wood was clear. Inoculation of deep stem wounds resulted in the greatest fluting with 76% of trees inoculated developing cankers.
Inoculation directly into stubs resulted in only small stem depressions that occurred in 17% of cases and the fungus was largely
contained within the branch trace. Tree response to inoculation with either ascospores or conidia of the Acremonium anamorph gave similar results in terms of canker development and fungal spread within the stem. Tree response to inoculation
was highly variable however: in one study 6% of trees did not respond to inoculation at all, while 26% produced severe cankers
regardless of inoculation method. A more thorough understanding of the infection mechanisms of N. fuckeliana will contribute to the development of better disease management protocols to prevent infection and disease development in
future plantation stock. 相似文献
126.
Recent plant diversity changes on Europe's mountain summits 总被引:2,自引:0,他引:2
Pauli H Gottfried M Dullinger S Abdaladze O Akhalkatsi M Benito Alonso JL Coldea G Dick J Erschbamer B Fernández Calzado R Ghosn D Holten JI Kanka R Kazakis G Kollár J Larsson P Moiseev P Moiseev D Molau U Molero Mesa J Nagy L Pelino G Puşcaş M Rossi G Stanisci A Syverhuset AO Theurillat JP Tomaselli M Unterluggauer P Villar L Vittoz P Grabherr G 《Science (New York, N.Y.)》2012,336(6079):353-355
In mountainous regions, climate warming is expected to shift species' ranges to higher altitudes. Evidence for such shifts is still mostly from revisitations of historical sites. We present recent (2001 to 2008) changes in vascular plant species richness observed in a standardized monitoring network across Europe's major mountain ranges. Species have moved upslope on average. However, these shifts had opposite effects on the summit floras' species richness in boreal-temperate mountain regions (+3.9 species on average) and Mediterranean mountain regions (-1.4 species), probably because recent climatic trends have decreased the availability of water in the European south. Because Mediterranean mountains are particularly rich in endemic species, a continuation of these trends might shrink the European mountain flora, despite an average increase in summit species richness across the region. 相似文献
127.
Marcel A. J. Toonen Chris Maliepaard Theo H. Reijmers Hilko van der Voet H. Dick Mastebroek Hetty C. van den Broeck Michel J. M. Ebskamp Waltraud Kessler Rudolf W. Kessler 《Euphytica》2004,140(1-2):39-45
Summary Fibre formation in hemp (Cannabis sativa L.) is a dynamic process. In order to follow this process, the chemical composition of the hemp stem was studied during plant development using the acid and neutral detergent fibre and lignin methods. Additionally, near infra-red spectroscopy was carried out. To predict the chemical composition of the stem samples partial least square (PLS) analysis was carried out. The developed PLS models can predict the level of %ADF and %NDF in the hemp bast and core samples. For %ADL, the models are only suited for either core or bast tissues and can not be used for both tissues simultaneously. 相似文献
128.
Dick Goossens 《CATENA》1985,12(4):373-402
A physical model, describing and predicting the lateral diffusion of a non-consolidated dust mass that settles down freely in air, is presented. It appears that in the total diffusion process a distinction has to be made between two (in origin totally different) types of diffusion. In the case of the first diffusion type, the settling dust mass acts as a closed system and all the particles fall with the same velocity. In the second diffusion type, the dust mass no longer acts as a closed system and each particle settles with its own fall velocity. Both of these diffusion types are investigated. The result is a set of four equations: the first and the second describe the starting point of the lateral diffusion, the third describes the lateral diffusion of the first type and the fourth describes the lateral diffusion of the second type. The equations are tested in six diffusion experiments and their validity seems to be very high.The physical and mathematical construction of the model allows extension of the formulae so that the frame of the model can be used in several other sedimentological, fluid dynamical or geomorphological research domains.The model shows clearly that the classical sedimentation techniques, which are very frequently used in grain size distribution measurements, can lead to completely wrong results if no extreme care is observed in connection with the concentration of the settling sediment. 相似文献
129.
Dick Wright 《Australian veterinary journal》1992,69(5):111-111
Book reviewed in this article:
Large Animal Neurology, A Handbook for Veterinary Clinicians, I G Mayhew 相似文献
Large Animal Neurology, A Handbook for Veterinary Clinicians, I G Mayhew 相似文献
130.