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排序方式: 共有82条查询结果,搜索用时 15 毫秒
1.
Eckhard Koch Annegret Schmitt Dietrich Stephan Carola Kromphardt Marga Jahn Hermann-Josef Krauthausen Gustaf Forsberg Sigrid Werner Tahsein Amein Sandra A. I. Wright Federico Tinivella Maria L. Gullino Steven J. Roberts Jan van der Wolf Steven P. C. Groot 《European journal of plant pathology / European Foundation for Plant Pathology》2010,127(1):99-112
The current study was initiated to evaluate the efficacy of physical methods (hot water, aerated steam, electron treatment) and agents of natural origin (resistance inducers, plant derived products, micro-organisms) as seed treatments of carrots for control of Alternaria dauci and A. radicina. Control of both Alternaria species by seed treatment with the resistance inducers was generally poor. Results were also not satisfactory with most of the formulated commercial micro-organism preparations. Based on the average of five field trials, one of these, BA 2552 (Pseudomonas chlororaphis), provided a low but significant increase in plant stand. Among the experimental micro-organisms, the best results were obtained with Pseudomonas sp. strain MF 416 and Clonostachys rosea strain IK726. A similar level of efficacy was provided by seed treatment with an emulsion (1%) of thyme oil in water. Good and consistent control was generally achieved with the physical methods aerated steam, hot water and electron treatment. Aerated steam treatment was, apart from the thiram-containing chemical standard, the best single treatment, and its performance may at least partially be due to extensive pre-testing, resulting in dosages optimally adapted to the respective seed lot. In some of the experiments the effect of the hot water treatment, which was tested at a fixed, not specifically adapted dosage, was significantly improved when combined with a Pseudomonas sp. MF 416 or C. rosea IK726 treatment. The results are discussed in relation to the outcome of experiments in which the same seed treatment methods and agents were tested in other seed-borne vegetable pathosystems. 相似文献
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Smith JD Cappa CD Wilson KR Messer BM Cohen RC Saykally RJ 《Science (New York, N.Y.)》2004,306(5697):851-853
A strong temperature dependence of oxygen K-edge x-ray absorption fine structure features was observed for supercooled and normal liquid water droplets prepared from the breakup of a liquid microjet. Analysis of the data over the temperature range 251 to 288 kelvin (-22 degrees to +15 degrees C) yields a value of 1.5 +/- 0.5 kilocalories per mole for the average thermal energy required to effect an observable rearrangement between the fully coordinated ("ice-like") and distorted ("broken-donor") local hydrogen-bonding configurations responsible for the pre-edge and post-edge features, respectively. This energy equals the latent heat of melting of ice with hexagonal symmetry (ice Ih) and is consistent with the distribution of hydrogen bond strengths obtained for the "overstructured" ST2 model of water. 相似文献
4.
Kuehner KA Marks SL Kass PH Sauter-Louis C Grahn RA Barutzki D Hartmann K 《Journal of Feline Medicine and Surgery》2011,13(4):251-258
The aim of this study was to determine the prevalence of Tritrichomonas foetus infection and associated clinical signs in purebred cats in Germany, to investigate the role of co-infection, and identify determinants of infection. Faecal specimens accompanied by epidemiological questionnaires were scored and collected from 230 purebred cats. Faeces were examined for trichomonads and other enteroparasites. The prevalence of T foetus was 15.7% among cats and 18.5% among catteries. An abnormal faecal score and history of diarrhoea were observed in 64% and 61% of T foetus-positive cats, respectively, and correlated significantly with infection. Co-infection, observed in 36% of T foetus-infected cats, was not associated with diarrhoea. Norwegian Forest cats were infected significantly more often than other breeds. No association was found with any environmental factors. This study demonstrated a high prevalence of symptomatic T foetus infections in purebred cats in Germany. Co-infection with other enteroparasites did not worsen clinical signs of trichomonosis. 相似文献
5.
Thomas Makary Rudolf Schulz Torsten Müller Carola Pekrun 《Archives of Agronomy and Soil Science》2020,66(6):847-857
ABSTRACTWinter wheat in northwestern Europe is often fertilized with several doses of calcium-ammonium-nitrate (CAN). For economy, farmers fertilize using a combination of N-doses. Here, we examined the necessity of N splitting (1–3) and application timing in experiments conducted in 2010 using a one-factorial fully randomized block design, and in 2011–2012 using a two-factorial split-plot design (four replicates). The study site, in southwestern Germany, had silty loam soil, and modern cultivars (2010: one cultivar, 2011–2012: three cultivars) with different genetic abilities to develop the yield components of interest were tested. A late first or single N application at stage BBCH 29/31 did not lead to differences in grain yields or protein contents compared to three N applications. However, a single N application at stage BBCH 25/27 resulted in a reduced protein content. Yield component development did not significantly differ among the cultivars. Early N application increased plant density but not yield. In two years, low plant densities were compensated by higher numbers of kernels per spike. Hence, under the tested conditions, the number of N applications could be reduced, as the high compensation ability of modern cultivars allows N fertilization consisting of two or even one application. 相似文献
6.
Radiative absorption enhancements due to the mixing state of atmospheric black carbon 总被引:3,自引:0,他引:3
CD Cappa TB Onasch P Massoli DR Worsnop TS Bates ES Cross P Davidovits J Hakala KL Hayden BT Jobson KR Kolesar DA Lack BM Lerner SM Li D Mellon I Nuaaman JS Olfert T Petäjä PK Quinn C Song R Subramanian EJ Williams RA Zaveri 《Science (New York, N.Y.)》2012,337(6098):1078-1081
Atmospheric black carbon (BC) warms Earth's climate, and its reduction has been targeted for near-term climate change mitigation. Models that include forcing by BC assume internal mixing with non-BC aerosol components that enhance BC absorption, often by a factor of ~2; such model estimates have yet to be clearly validated through atmospheric observations. Here, direct in situ measurements of BC absorption enhancements (E(abs)) and mixing state are reported for two California regions. The observed E(abs) is small-6% on average at 532 nm-and increases weakly with photochemical aging. The E(abs) is less than predicted from observationally constrained theoretical calculations, suggesting that many climate models may overestimate warming by BC. These ambient observations stand in contrast to laboratory measurements that show substantial E(abs) for BC are possible. 相似文献
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Ramspott S Hartmann K Sauter-Louis C Weber K Wehner A 《Journal of Feline Medicine and Surgery》2012,14(4):262-266
Adrenal function may be altered in animals with hyperthyroidism. The aim of the study was to assess adrenal function of hyperthyroid cats (n = 17) compared to healthy cats (n = 18) and cats with chronic diseases (n = 18). Adrenal function was evaluated by adrenocorticotropic hormone (ACTH) stimulation test and the urinary cortisol to creatinine ratio (UCCR) was determined. Length and width of both adrenal glands were measured via ultrasound. Hyperthyroid cats had significantly higher cortisol levels before and after stimulation with ACTH than the other groups. However, the UCCR was not elevated in hyperthyroid cats. The size of the adrenal glands of hyperthyroid cats was not significantly different from the size of those of healthy cats. The results indicate that cats with hyperthyroidism have a higher cortisol secretory capacity in a hospital setting. The normal size of the adrenal glands suggests that cortisol levels may not be increased permanently. 相似文献
9.
Englert T Lutz H Sauter-Louis C Hartmann K 《Journal of Feline Medicine and Surgery》2012,14(6):392-398
Most studies that investigate the prevalence of infections with feline leukemia virus (FeLV) are based on the detection of p27 antigen in blood, but they do not detect proviral DNA to identify the prevalence of regressive FeLV infections. The aim of the present study was to assess the prevalence and status of FeLV infection in cats in Southern Germany. P27 antigen enzyme-linked immunosorbent assay (ELISA), anti-p45 antibody ELISA, DNA polymerase chain reaction (PCR) of blood and RNA PCR of saliva were performed. Nine out of 495 cats were progressively (persistently) infected (1.8%) and six were regressively (latently) infected (1.2%). Cats with regressive infections are defined as cats that have been able to overcome antigenemia but provirus can be detected by PCR. Twenty-two unvaccinated cats likely had abortive infections (regressor cats), testing FeLV antigen- and provirus-negative but anti-p45 antibody-positive. Most of the FeLV-vaccinated cats did not have anti-FeLV antibodies. Both progressive, as well as regressive infections seem to be rare in Germany today. 相似文献
10.
Eduardo P. Cappa Alvin D. Yanchuk Charlie V. Cartwright 《Annals of Forest Science》2012,69(5):627-640