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11.
Stefan Fleck Nathalie Cools Bruno De Vos Henning Meesenburg Richard Fischer 《Annals of Forest Science》2016,73(4):945-957
Key message
Aggregated, consolidated, and derived soil physicochemical data of 286 ICP Forests Level II plots were completed with soil hydraulic properties for integrated use with forest monitoring data. Database access should be requested at http://icp-forests.net . Metadata associated available at https://metadata-afs.nancy.inra.fr/geonetwork/apps/georchestra/?uuid=153e599e-6624-4e2b-b862-8124386ea9cd&hl=engContext
The ICP Forests database is one of the most comprehensive forest ecosystem datasets in Europe and contains the accumulated results of more than two decades of harmonised forest monitoring all over Europe.Aims
The aim of this paper is to share knowledge on the ICP Forests Level II soil data for broader use among forest scientists.Methods
After standard analysis, quality checks, aggregation, and calculation of derived variables (e.g. nutrient stocks, base saturation, C:N ratio, and water retention parameters), data have been gathered into a static database (AFSCDB.LII.2.2), which will be updated to new versions as soon as new measurements become available.Results
The database provides a basis for the combined evaluation of up to 130 unique soil variables of 286 plots with dynamic data on tree growth, ground vegetation, foliar chemistry, crown condition, tree phenology, leaf area index, ozone injury, litterfall, soil solution chemistry, deposition, ambient air quality, and meteorological data assessed on the same plots.Conclusion
The unprecedented comprehensiveness and level of detail in this newly aggregated database may overcome existing restrictions so far impeding the realisation of large-scale forest ecosystem studies in Europe.12.
Inductively coupled plasma mass‐spectrometric determination of platinum in excretion products of client‐owned pet dogs 下载免费PDF全文
T. Janssens E. E. M. Brouwers J. P. de Vos N. de Vries J. H. M. Schellens J. H. Beijnen 《Veterinary and comparative oncology》2015,13(2):124-132
Residues of antineoplastic drugs in canine excretion products may represent exposure risks to veterinary personnel, owners of pet dogs and other animal care‐takers. The aim of this study was to measure the extent and duration of platinum (Pt) excretion in pet dogs treated with carboplatin. Samples were collected before and up to 21 days after administration of carboplatin. We used validated, ultra‐sensitive, inductively coupled plasma‐mass spectrometry assays to measure Pt in canine urine, faeces, saliva, sebum and cerumen. Results showed that urine is the major route of elimination of Pt in dogs. In addition, excretion occurs via faeces and saliva, with the highest amounts eliminated during the first 5 days. The amount of excreted Pt decreased over time but was still quantifiable at 21 days after administration of carboplatin. In conclusion, increased Pt levels were found in all measured excretion products up to 21 days after administration of carboplatin to pet dogs, with urine as the main route of excretion. These findings may be used to further adapt current veterinary guidelines on safe handling of antineoplastic drugs and treated animals. 相似文献
13.
The biochemical, morphological and virulence profiles of Bacillus anthracis isolated in the Kruger National Park 总被引:1,自引:0,他引:1
M W Odendaal P M Pieterson V de Vos A D Botha 《The Onderstepoort journal of veterinary research》1991,58(1):21-26
The biochemical, morphological and virulence profiles of 44 Bacillus anthracis isolates, obtained from various localities and carcass remains of wild animals in the Kruger National Park, South Africa, were examined. The morphological characteristics tested for included: the formation of capsules on bicarbonate agar, the motility of the vegetative organism, the presence of haemolysis on blood tryptose agar, the sensitivity of the vegetative organism to bacteriophage, the production of lecithinase on egg yolk agar, the liquefaction (hydrolysis) of gelatine and the capability of each isolate to produce mucoid colonies when grown on bicarbonate agar with horse serum in an atmosphere containing CO2. The API 50CHB and 20E systems were used to evaluate the biochemical activity of each isolate. The virulence of each isolate was determined by its LD50, using an inbred line of Balb/C mice. A clear pattern in the biochemical reactions emerged that appeared to be specific for each isolate. On the API 50CHB test strip, only 2 of the 44 isolates gave a 100% positive reaction to all 10 of the biochemical substances to which it was supposed to react, 9 gave positive results to 90%, 19 were positive to 80%, and 14 were positive to 70%. The reactions on the API 20E were completely different from what was expected, with only 1 of the biochemical activities (gelatinase production) showing a positive reaction to all the isolates. The virulence test indicated that 27/44 isolates could be regarded as highly virulent with a LD50 of less than 1,000 organisms, and the rest of the isolates as virulent with a LD 50 of 1,001-10,000 organisms.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
14.
T F Müller P Schuster A C Vos T Selhorst U D Wenzel A M Neubert 《American journal of veterinary research》2001,62(7):1154-1158
OBJECTIVE: To determine effect of maternal antibodies on immune response to oral vaccination against rabies in young foxes. ANIMALS: 250 cubs from 48 vixens. PROCEDURE: Sera were obtained from cubs of 36 vaccinated (maternally vaccinated [MV+]) and 12 nonvaccinated (MV-) vixens between 23 and 71 days of age and tested for neutralizing antibodies. Seventy-one MV+ cubs and 33 MV-cubs were vaccinated orally with modified-live virus vaccine SAD B19. Geometric mean titer (GMT) was determined in these cubs approximately 21, 39, and 57 days after vaccination. In a subsequent experiment, 10 vaccinated MV+ cubs, 6 vaccinated MV- cubs, and 6 control cubs were challenge inoculated with virulent rabies virus approximately 100 days after vaccination. RESULTS: Serum GMT of nonvaccinated MV cubs (0.23 U/ml) was significantly greater than that of non-vaccinated MV- cubs (0.15 U/ml). The GMT of vaccinated MV+ cubs 21, 39, and 57 days after vaccination were 2.85, 2.11, and 0.79 U/ml, respectively, and were significantly less than those of vaccinated MV- cubs (12.19, 6.76, and 4.02 U/ml, respectively). All challenge-inoculated cubs with GMT < 0.5 U/ml succumbed to rabies. CONCLUSION AND CLINICAL RELEVANCE: Partially impaired immune response in cubs < 8 weeks old from vaccinated vixens causes insufficient protection against rabies. Inhibition of the immune response persists longer than the period during which maternal antibodies are detectable. Thus, oral vaccination campaigns for young foxes in areas where vaccination has been performed need to be reconsidered. 相似文献
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17.
Small-scale landscape elements, such as ditch banks are an important remaining source of biodiversity in many agricultural landscapes, including the Western Peat District in the Netherlands. Unfortunately, plant species richness is declining even in these habitats. To understand the factors threatening biodiversity, we studied demographic traits (occupancy, trend, colonisation and extinction) for a large number of plant species, in a 25-year long data set. We developed a method to investigate the relative importance of colonisation and extinction for species increase and decrease in multi-species assemblages. We show that colonisation has been more important for determining species trends than extinction. Decreasing species were small and characterised by low nutrient tolerance and high light requirements, indicating that competitive ability influences species trends. The mechanism by which high nutrient levels reduce plant diversity appears to be closely related to colonisation (germination and seedling establishment). Local management should therefore continue to focus on nutrient reduction and the creation of regeneration sites. Yet, these measures will be insufficient for restoring species richness since isolation also hampers species increase. Therefore, to maximise the effects of local management, additional regional management solutions are required to improve seed dispersal for example, from nature reserves. 相似文献
18.
The sex organs of the male are more resistant to dietary deficiencies, the animals showing only retrogression along with a significant loss in weight. Testosterone and gonadotropic hormone (of pregnant mare serum) produce a small but definite restorative effect. Oral administration of estrin to females depresses the food intake, while testosterone, and less so the gonadotropic hormone in males produces the opposite effect. This effect can be regarded as evidence of the dietary significance of these two hormones. The expenses of the present investigation were defrayed by the U. S. Vitamin Corporation, of New York City. 相似文献
19.
Sound velocities in dense hydrogen and the interior of jupiter 总被引:1,自引:0,他引:1
Sound velocities in fluid and crystalline hydrogen were measured under pressure to 24 gigapascals by Brillouin spectroscopy in the diamond anvil cell. The results provide constraints on the intermolecular interactions of dense hydrogen and are used to construct an intermolecular potential consistent with all available data. Fluid perturbation theory calculations with the potential indicate that sound velocities in hydrogen at conditions of the molecular layer of the Jovian planets are lower than previously believed. Jovian models consistent with the present results remain discrepant with recent free oscillation spectra of the planet by 15 percent. The effect of changing interior temperatures, the metallic phase transition depth, and the fraction of high atomic number material on Jovian oscillation frequencies is also investigated with the Brillouin equation of state. The present data place strong constraints on sound velocities in the Jovian molecular layer and provide an improved basis for interpreting possible Jovian oscillations. 相似文献
20.
Dimerization of the extracellular domain of the human growth hormone receptor by a single hormone molecule 总被引:51,自引:0,他引:51
B C Cunningham M Ultsch A M De Vos M G Mulkerrin K R Clauser J A Wells 《Science (New York, N.Y.)》1991,254(5033):821-825
Human growth hormone (hGH) forms a 1:2 complex with the extracellular domain of its receptor-binding protein (hGHbp) as studied by crystallization, size exclusion chromatography, calorimetry, and a previously undescribed fluorescence quenching assay. These and other experiments with protein engineered variants of hGH have led to the identification of the binding determinants for two distinct but adjacent sites on hGH for the hGHbp, and the data indicated that there are two overlapping binding sites on the hGHbp for hGH. Furthermore, the binding of hGH to the hGHbp occurred sequentially; a first hGHbp molecule bound to site 1 on hGH and then a second hGHbp bound to site 2. Hormone-induced receptor dimerization is proposed to be relevant to the signal transduction mechanism for the hGH receptor and other related cytokine receptors. 相似文献