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151.
Katja Voss Dr med vet Diplomate ECVS Luca Galeandro Dr med vet Thomas Wiestner BS El Eng Michael Haessig Prof Dr med vet Pierre M. Montavon Prof Dr med vet 《Veterinary surgery : VS》2010,39(7):863-869
Objective: To evaluate the relationship of body weight (BW) and size, dog velocity, and vertical ground reaction forces (GRF) from a large number of dogs of various sizes. Study Design: Clinical research. Animals: Orthopedically healthy dogs (n=129) Methods: BW and dog size, represented as height at the withers (WH), were obtained. Stance times (ST), vertical impulses (VI), and peak vertical forces (PVF) of thoracic and pelvic limbs were measured on a force plate at controlled trotting speed. They were evaluated against BW and WH using linear regression analysis in absolute (nonnormalized) values, and when normalized to BW and/or body size according to the theory of dynamic similarity. Relative velocities were calculated for each dog. Results: Absolute ST, VI, and PVF showed strong positive correlations with BW and/or body size. When GRFs were normalized to BW, correlations with body size were markedly reduced, but remained positive for VI, and turned negative for PVF. Normalizing the time‐dependent variables (ST and VI) also to WH eliminated most size influence. A small dependency of fully normalized GRF on body size remained that was because of differences in relative velocity between dogs of different sizes. Reference values for the fully normalized data are given. Conclusions: The inherent relationship between BW, body size, dog velocity, and vertical GRF was demonstrated. Clinical Relevance: BW, body size, and relative dog velocity must be accounted for when wanting to obtain GRF variables that are comparable between different dogs. 相似文献
152.
Retrospective evaluation of 155 adult equids and 21 foals with tetanus from Western,Northern, and Central Europe (2000–2014). Part 2: Prognostic assessment 
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下载免费PDF全文 Gaby van Galen DVM PhD DECEIM Joke Rijckaert DVM Tim Mair BVSc PhD DECEIM Helene Amory DVM PhD DECEIM Lara Armengou DVM PhD DECEIM Barbora Bezdekova DVM PhD DECEIM Inge Durie DVM DECEIM Rikke Findshøj Delany DVM Nathalie Fouché DVM Laura Haley MVB Michael Hewetson BVSc DECEIM Rene van den Hoven DVM PhD DECEIM Anna Kendall DVM DECEIM Fernando Malalana DVM DECEIM MRCVS Jessika Muller Cavalleri DVM DECEIM PhD Tresemiek Picavet DVM DECEIM Katja Roscher DVM DECEIM Denis Verwilghen DVM PhD DECVS Cornélie Westermann DVM PhD DECEIM Claude Saegerman DVM PhD DECVPH 《Journal of Veterinary Emergency and Critical Care》2017,27(6):697-706
153.
Geertje?J.?PronkEmail author Katja?Heister Cordula?Vogel Doreen?Babin J?rg?Bachmann Guo-Chun?Ding Franziska?Ditterich Martin?H.?Gerzabek Julia?Giebler Michael?Hemkemeyer Ellen?Kandeler Yamuna?Kunhi Mouvenchery Anja?Miltner Christian?Poll Gabriele?E.?Schaumann Kornelia?Smalla Annelie?Steinbach Irina?Tanuwidjaja Christoph?C.?Tebbe Lukas?Y.?Wick Susanne?K.?Woche Kai?U.?Totsche Michael?Schloter Ingrid?K?gel-Knabner 《Biology and Fertility of Soils》2017,53(1):9-22
Our understanding of the interactions between minerals, organic matter, and microorganisms at so-called biogeochemical interfaces in soil is still hampered by the inherent complexity of these systems. Artificial soil maturation experiments can help to bridge a gap in complexity between simple abiotic sorption experiments and larger-scale field experiments. By controlling other soil-forming factors, the effect of a particular variable can be identified in a simplified system. Here, we review the findings of a series of artificial soil incubation experiments with the aim of revealing general trends and conclusions. The artificial soils were designed to determine the effect of mineral composition and charcoal presence on the development of abiotic and biotic soil properties during maturation. In particular, the development of soil aggregates, organic matter (OM) composition and turnover, sorption properties, and the establishment of microbial community composition and function were considered. The main objectives of the research were to determine (1) how surface properties and sorption of chemicals modify biogeochemical interfaces; (2) how much time is required to form aggregates from mixtures of pure minerals, OM, and a microbial inoculum; and (3) how the presence of different mineral and charcoal surfaces affects aggregation, OM turnover, and the development of microbial community composition. 相似文献
154.
Katja Oing Alexander Gröngröft Annette Eschenbach 《Journal of Soils and Sediments》2018,18(9):3020-3030
Purpose
The utilization of dredged material in dike construction as a substitute for traditionally used aged marsh sediment is considered an advisable option with respect to ecological as well as economic aspects. As a prerequisite to the application, the equivalency with respect to soil physical and mechanical properties of the materials has to be verified. Previous investigations on the compactibility of dredged materials used for dike construction had shown that the bulk densities of these materials were considerably lower than bulk densities of aged marsh sediments. The aim of the investigations presented in this paper was to analyze whether the compactibility of the processed dredged material could be improved by enhanced dewatering of the material prior to construction. It was hypothesized that a decreased water content of the material would allow higher bulk densities to be achieved during construction and hence the soil physical properties would become more comparable to those of the aged marsh sediments.Materials and methods
To examine whether the compactibility of dredged material can be enhanced by pre-drying, Proctor tests were carried out at different initial water contents. Moreover, it was examined whether the temperature of oven-drying at 30 and 105 °C affects the compactibility of these materials and whether ripening, i.e., the repeated drying and wetting of the dredged material under natural and laboratory conditions, can improve their compactibility.Results and discussion
The investigations on the effect of the various further processing methods showed that the compactibility and therefore the suitability of processed dredged material for dike construction can be improved by air-drying. A linear relationship between dehydration and Proctor density was found. Air-drying to water contents of 10% dry weight (DW) resulted in an improvement of the Proctor density of up to 11%. However, the tests on the effect of the drying temperature on the compactibility showed that oven-drying had no additional effect on the compactibility of the dredged materials. Ripening under laboratory and natural conditions did not lead to statistically significant changes in the compactibility of the processed dredged material either.Conclusions
Air-drying of processed dredged material to water contents less than 10% DW is considered to be a useful pre-treatment option to improve the compaction behavior of processed dredged material and to obtain a better functional equivalency with traditionally used dike construction materials such as fine-grained aged marsh sediments.155.
Rachele Weintraub Etzel Garrido Katja Poveda 《American Journal of Potato Research》2018,95(6):642-649
Tolerance is a type of defense that allows plants to attenuate the negative effects of herbivory. Tolerance has been shown to be context-dependent, contingent on abiotic and biotic factors such as nutrients and plant age. Here, we determine the simultaneous effect of herbivory at different phenological stages and nitrogen regimen on the potato’s ability to tolerate herbivory. We subjected young and blooming plants of two potato varieties to 50% injury by Colorado Potato Beetle in low and high nitrogen environments to determine their effects on tuber yield and plant tolerance. All plants in the high nitrogen treatment expressed higher yield and tolerance compared to those in the low nitrogen treatment. Control plants expressed higher yield than plants in either herbivory treatment. There was a variety by phenological stage of herbivory interaction showing that phenological-based tolerance expression within species is genotype dependent. 相似文献
156.
Lothar Beyer Katja Tielbrger Hans-P. Blume Ulrich Pfisterer Kristina Pingpank Dieter Podlech 《植物养料与土壤学杂志》1998,161(4):347-356
Soils are suggested to be an important factor influencing the vegetation pattern. In order to prove this hypothesis in an arid and sandy Negev ecosystem of longitudinal dunes and interdune corridors near Nizzana, Israel, the distribution of soil units and plant communities were compared on a very small-distance level. The Nizzana site has a size of nearly 100 ha. 250 soil pits with 3–5 horizons were mapped and sampled within the soil geographical monitoring. Soil water capacity and cation exchange capacity were estimated from the field data. In addition 176 plots of 100 m2 were established around the soil pits with emphasis on plants, coveting the environmental gradient across the dune ridges. Plant mapping plots were arranged into groups with the same dominating perennial species and a key for the vegetation mapping was developed. In the investigated desert site topography, soil surface crust, soil texture and salt content partly can explain the distribution of plant communities. A soil classification proposal is based on these parameters and is a useful tool to indicate correlations between soil units and the vegetation pattern. Nevertheless, dependent on topography and surface and/or subsurface water flow as well as the occurrence of “fertile islands” the moisture and nutrient regimes influence the vegetation pattern with respect to plant growth to a greater extent than the soils themselves. 相似文献
157.
Spatial occurrence of major tree species groups in Europe derived from multiple data sources 总被引：1，自引：0，他引：1
Pan-European distribution maps have been compiled for six main species groups in Europe. The aim was to combine detailed tree species information from plot data of the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) with other existing spatial and statistical information on forests. The applied method involves the interpolation of the plot data using the geo-statistical interpolation method kriging and a scaling and calibration procedure which makes the maps correspond both to the Forest map of Europe on pixel level and to national forest inventory statistics at regional or national level. Output is a set of European-wide maps with a resolution of 1 km, showing the proportion of the main tree species groups as a percent of the total land area. The maps are considered to be potentially valuable input for various applications in the forestry and biodiversity field at a pan-European scale. 相似文献
158.
159.
Katja Mustonen Anneli Niemi Marja Raekallio Mari Heinonen Olli AT Peltoniemi Mari Palviainen Mia Siven Marikki Peltoniemi Outi Vainio 《Acta veterinaria Scandinavica》2012,54(1):55
Background
Ketoprofen is a non-steroidal anti-inflammatory drug which has been widely used for domestic animals. Orally administered racemic ketoprofen has been reported to be absorbed well in pigs, and bioavailability was almost complete. The objectives of this study were to analyze R- and S-ketoprofen concentrations in plasma after oral (PO) and intra muscular (IM) routes of administration, and to assess the relative bioavailability of racemic ketoprofen for both enantiomers between those routes of administration in growing pigs.Methods
Eleven pigs received racemic ketoprofen at dose rates of 4 mg/kg PO and 3 mg/kg IM in a randomized, crossover design with a 6-day washout period. Enantiomers were separated on a chiral column and their concentrations were determined by liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were calculated and relative bioavailability (Frel) was determined for S and R –ketoprofen.Results
S-ketoprofen was the predominant enantiomer in pig plasma after administration of the racemic mixture via both routes. The mean (± SD) maximum S-ketoprofen concentration in plasma (7.42 mg/L ± 2.35 in PO and 7.32 mg/L ± 0.75 in IM) was more than twice as high as that of R-ketoprofen (2.55 mg/L ± 0.99 in PO and 3.23 mg/L ± 0.70 in IM), and the terminal half-life was three times longer for S-ketoprofen (3.40 h ± 0.91 in PO and 2.89 h ± 0.85 in IM) than R-ketoprofen (1.1 h ± 0.90 in PO and 0.75 h ± 0.48 in IM). The mean (± SD) relative bioavailability (PO compared to IM) was 83 ± 20% and 63 ± 23% for S-ketoprofen and R-ketoprofen, respectively.Conclusions
Although some minor differences were detected in the ketoprofen enantiomer concentrations in plasma after PO and IM administration, they are probably not relevant in clinical use. Thus, the pharmacological effects of racemic ketoprofen should be comparable after intramuscular and oral routes of administration in growing pigs. 相似文献160.