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1.
W. Hofmann 《Forstwissenschaftliches Centralblatt》1960,79(7-8):202-206
Der Verfasser führte in den Jahren 1957 und 1958 im Rahmen eines Forschungsauftrages der Deutschen Forschungsgemeinschaft als wissenschaftliche Hilfskraft von Herrn Prof. Dr.H. Zeidier (Botanisches Institut der Universität Würzburg) vegetationskundliche und bodenkundliche Untersuchungen an Laubwäldern in der näheren und weiteren Umgebung von Würzburg durch. Dabei hatte er Gelegenheit, sich einen Überblick über die Vegetations- und Bodenverhältnisse dieses Gebietes zu beschaffen. So konnte er nach dem starken Sturm am 1. August 1958 Beobachtungen über den Zusammenhang zwischen Bodenverhältnissen und Windwurfschäden im Gramschatzer und Guttenberger Wald bei Würzburg sammeln, die für waldbauliche Fragen von Interesse sein dürften. 相似文献
2.
Christoph Hofmann 《Forstwissenschaftliches Centralblatt》1939,61(5):137-142
Ohne Zusammenfassung 相似文献
3.
4.
Dr. Ch. Hofmann 《Journal of pest science》1935,11(11):129-130
Ohne Zusammenfassung 相似文献
5.
6.
A survey of Newcastle disease in Swiss laying-hen flocks using serological testing and simulation modelling 总被引:1,自引:0,他引:1
Newcastle disease (ND) is a highly contagious viral disease of birds particularly domestic poultry. Switzerland is currently declared free from ND; since vaccination is prohibited, the detection of antibodies against ND virus (NDV) results in the destruction of the respective flock (stamping-out policy). However, in 1995 and 1996, antibody-positive flocks were detected and sporadic ND outbreaks even occurred in Switzerland. Therefore, a serosurvey was done to look for evidence of NDV infections in Swiss laying-hen flocks. The survey was designed to provide 95% confidence of detecting at least one seropositive flock if the flock prevalence were 1%. Thirty blood samples from each of 260 commercial laying-hen flocks were collected during 1996 in a central poultry slaughterhouse. Sera were screened for NDV antibodies with a commercial blocking enzyme-linked immunosorbent assay (ELISA). Samples with a questionable or positive test result were retested with the same ELISA. A stochastic computer model was applied to define a cut-off number of test-positive samples to help to differentiate between true- and false-positive flocks and to estimate the true flock prevalence of infection. Four flocks were identified as NDV-seropositive and the NDV true seroprevalence among commercial laying-hen flocks in Switzerland was most likely between 1.35 and 1.55%. This indicates that Swiss laying-hen and parental flocks with more than 150 animals have been in contact with strains of NDV that cause subclinical infection in chicken, because no clinical symptoms have been observed. In this context, computer simulation was a useful technique to interpret survey results. 相似文献
7.
Frank O Blumberg S Krümpel G Hofmann T 《Journal of agricultural and food chemistry》2008,56(20):9581-9585
Recent investigations on the bitterness of coffee as well as 5- O-caffeoyl quinic acid roasting mixtures indicated the existence of another, yet unknown, bitter lactone besides the previously identified bitter compounds 5- O-caffeoyl- muco-gamma-quinide, 3- O-caffeoyl-gamma-quinide, 4- O-caffeoyl- muco-gamma-quinide, 5- O-caffeoyl- epi-delta-quinide, and 4- O-caffeoyl-gamma-quinide. In the present study, this orphan bitter lactone was isolated from the reaction products generated by dry heating of 5- O-caffeoylquinic acid model, and its structure was determined as the previously unreported 3- O-caffeoyl- epi-gamma-quinide by means of liquid chromatography-mass spectrometry (LC-MS) and one-/two-dimensional NMR experiments. The occurrence of this bitter lactone, exhibiting a low bitter recognition threshold of 58 micromol/L, in coffee beverages could be confirmed by LC-MS/MS (negative electrospray ionization) operating in the multiple reaction monitoring mode. 相似文献
8.
Fan S Baets R Petrov A Yu Z Joannopoulos JD Freude W Melloni A Popović M Vanwolleghem M Jalas D Eich M Krause M Renner H Brinkmeyer E Doerr CR 《Science (New York, N.Y.)》2012,335(6064):38; author reply 38
We show that the structure demonstrated by Feng et al. (Reports, 5 August 2011, p. 729) cannot enable optical isolation because it possesses a symmetric scattering matrix. Moreover, one cannot construct an optical isolator by incorporating this structure into any system as long as the system is linear and time-independent and is described by materials with a scalar dielectric function. 相似文献
9.
Nespeca G Grest P Rosenkrantz WS Ackermann M Favrot C 《American journal of veterinary research》2006,67(12):2036-2041
OBJECTIVE: To detect and partially characterize papillomavirus (PV) DNA in squamous cell carcinoma (SCC) tumor specimens from cats. SAMPLE POPULATION: 54 formalin-fixed paraffinembedded skin biopsy specimens were examined. Specimens originated from Bowenoid in situ SCC (BISC; n = 21), invasive SCC (22), and skin affected by miscellaneous nonneoplastic conditions (11). PROCEDURES: Samples from each tissue block underwent DNA extraction after deparaffinization, and PCR assays were performed. Two sets of primers derived from PV E1 were used. The first set of primers was designed for the narrow-range PCR assay and was able to generate amplification products of feline PV (FePV), canine oral PV, or closely related PVs. The second set of primers was selected for the broad-range PCR assay because of its ability to amplify DNA from 64 human PVs. Sequence analysis of each amplified DNA was performed. RESULTS: 1 of the 21 specimens of BISC was positive for PV DNA on the basis of narrow-range PCR assay results, whereas all the other specimens (BISC, invasive SCC, and controls) had negative results for PV DNA. In contrast, 5 of 21 BISC specimens and 4 of 22 invasive SCC specimens were positive for PV DNA on the basis of broad-range PCR assay results. Sequence analysis revealed that only 1 specimen was infected by a virus closely related to classic FePV. In the 8 other specimens positive for PV DNA, DNA of unknown PVs was uncovered. CONCLUSIONS AND CLINICAL RELEVANCE: Bowenoid in situ SCC and invasive SCC of cats may be associated with PVs of genetic diversity. 相似文献
10.
Wolfgang Ahlf Henner Hollert Helga Neumann-Hensel Mathias Ricking 《Journal of Soils and Sediments》2002,2(1):37-42
The recommendations presented in this paper use an integrated hierarchical approach combining toxicological, chemical and
ecological information to assess and evaluate the quality of sediments. For this reason, biological methods, in combination
with the tools of chemical analysis, are given priority when examining the quality of the sediment to establish adverse effects.
The trigger is the biotest, instead of chemical methods commonly used. The individual methods are presented for a German approach
and can be adopted to other countries by applying ISO, OECD methods. Support is provided on how to best integrate data generated
using different assessment tools. Keywords: Bioassays; biological and chemical analysis; ecotoxicology; integrated assessment;
sediment assessment; sediment quality; stepwise strategy 相似文献