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881.
Valentin Eckart Takuya Yamaguchi Kati Franzke Sven M. Bergmann Pierre Boudinot Edwige Quillet Motokazu Kawanobe Neila Alvarez de Haro Uwe Fischer 《Journal of fish diseases》2019,42(2):181-187
The production of piscine viruses, in particular of koi herpesvirus (KHV, CyHV‐3) and infectious salmon anaemia virus (ISAV), is still challenging due to the limited susceptibility of available cell lines to these viruses. A number of cell lines from different fish species were compared to standard diagnostic cell lines for KHV and ISAV regarding their capability to exhibit a cytopathic effect (CPE) and to accumulate virus. Two cell lines, so far undescribed, appeared to be useful for diagnostic purposes. Fr994, a cell line derived from ovaries of rainbow trout (Oncorhynchus mykiss), produced constantly high ISA virus (ISAV) titres and developed a pronounced CPE even at high cell passage numbers, while standard cell lines are reported to gradually loose these properties upon propagation. Another cell line isolated from the head kidney of common carp (Cyprinus carpio), KoK, showed a KHV induced CPE earlier than the standard cell line used for diagnostics. A third cell line, named Fin‐4, established from the fin epithelium of rainbow trout did not promote efficient replication of tested viruses, but showed antigen sampling properties and might be useful as an in vitro model for virus uptake or phagocytosis. 相似文献
882.
883.
Aloysius T.M. van Helmond Lars O. Mortensen Kristian S. Plet‐Hansen Clara Ulrich Coby L. Needle Daniel Oesterwind Lotte Kindt‐Larsen Thomas Catchpole Stephen Mangi Christopher Zimmermann Hans Jakob Olesen Nick Bailey Heidrikur Bergsson Jrgen Dalskov Jon Elson Malo Hosken Lisa Peterson Howard McElderry Jon Ruiz Johanna P. Pierre Claude Dykstra Jan Jaap Poos 《Fish and Fisheries》2020,21(1):162-189
Since the beginning of the 21st century, electronic monitoring (EM) has emerged as a cost‐efficient supplement to existing catch monitoring programmes in fisheries. An EM system consists of various activity sensors and cameras positioned on vessels to remotely record fishing activity and catches. The first objective of this review was to describe the state of play of EM in fisheries worldwide and to present the insights gained on this technology based on 100 EM trials and 12 fully implemented programmes. Despite its advantages, and its global use for monitoring, progresses in implementation in some important fishing regions are slow. Within this context, the second objective was to discuss more specifically the European experiences gained through 16 trials. Findings show that the three major benefits of EM were as follows: (a) cost‐efficiency, (b) the potential to provide more representative coverage of the fleet than any observer programme and (c) the enhanced registration of fishing activity and location. Electronic monitoring can incentivize better compliance and discard reduction, but the fishing managers and industry are often reluctant to its uptake. Improved understanding of the fisher's concerns, for example intrusion of privacy, liability and costs, and better exploration of EM benefits, for example increased traceability, sustainability claims and market access, may enhance implementation on a larger scale. In conclusion, EM as a monitoring tool embodies various solid strengths that are not diminished by its weaknesses. Electronic monitoring has the opportunity to be a powerful tool in the future monitoring of fisheries, particularly when integrated within existing monitoring programmes. 相似文献
884.
Franc-Christophe Baurens Jean-Louis Noyer Claire Lanaud Pierre Jean Laurent Lagoda 《Euphytica》1998,99(2):137-142
Alu sequences are a major repetitive element of the primate genome. To date Alu sequences have seldom been reported in plant
genomes. We report here an inter-Alu PCR like genomic profiling in banana using a single primer designed from a human Alu
sequence. The different Musa species involved in the complex genome of banana cultivars can thus be discriminated. The use
of this technique for monitoring germplasm or genotyping cultivars is discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
885.
Identification and preliminary characterization of a 75-kDa hemin- and hemoglobin-binding outer membrane protein of Actinobacillus pleuropneumoniae serotype 1
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Marie Archambault Jose Labrie Clment R. Rioux France Dumas Pierre Thibault Christopher Elkins Mario Jacques 《Canadian journal of veterinary research》2003,67(4):271-277
The reference strains representing serotypes 1 to 12 of Actinobacillus pleuropneumoniae biotype 1 were examined for their ability to utilize porcine hemoglobin (Hb) or porcine hemin (Hm) as iron sources for growth. In a growth promotion assay, all of the reference strains were able to use porcine Hb, and all strains except 2 were able to use porcine Hm. Using a preliminary characterization procedure with Hm- or Hb-agarose, Hm- and Hb-binding outer membrane proteins (OMPs) of approximately 75 kDa were isolated from A. pleuropneumoniae serotype 1 strain 4074 grown under iron-restricted conditions. Matrix-assisted laser desorption ionization/time-of-flight (MALDI-TOF) analysis revealed a number of common tryptic peptides between the Hb-agarose- and Hm-agarose-purified 75 kDa OMPs, strongly suggesting that these peptides originate from the same protein. A database search of these peptide sequences revealed identities with proteins from various Gram-negative bacteria, including iron-regulated OMPs, transporter proteins, as well as TonB-dependent receptors. Taken together, our data suggest that A. pleuropneumoniae synthesizes potential Hm- and Hb-binding proteins that could be implicated in the iron uptake from porcine Hb and Hm. 相似文献
886.
Pierre G. Bosio Edwin R. Cole Brian L. Mathews Austin P Woodbridge A. Neill Wright 《Pest management science》1982,13(1):63-71
Residue analytical studies are reported on soils from trial sites in the UK and France following applications of flamprop-isopropyl ( I ) to growing crops. The analytical procedure developed allowed the determination of I and its hydrolysis product N-benzoyl-N-(3-chloro-4-fluorophenyl)-DL -alanine ( II ). The residues in the soil often increased during some weeks after application due to transfer of I from the crop to the soil, so that measurement of the initial half-life of I in soil was unusually difficult. However, it was probably within the range 4–20 weeks. Both I and II were detected in field soils, but neither compound was persistent in soil and normally little or no carry-over of residues occurred from one season to the next, although greater persistence was found in one Kentish trial. 相似文献
887.
Pierre G. Bosio Edwin R. Cole Austin P. Woodbridge Brian L. Mathews A. Neill Wright 《Pest management science》1982,13(1):72-77
Residue data are reported for flamprop-isopropyl ( I ) in barley grain and straw samples following applications of the herbicide to crops grown in eight countries. The samples were analysed for I and its hydrolysis product N-benzoyl-N-(3-chloro-4-fluorophenyl)-DL -alanine ( II ). Following recommended applications (normally 1 kg ha?1 at Feekes scale G-I/J), residues of I and II in the grain were low (90% were <0.02 mg kg?1 for I , 86% were <0.06 mg kg?1 for II , levels which were essentially the limits of determination). Residues in straw were higher and more variable, but again 63 and 77% of samples were below 1 mg kg?1 for I and II , respectively. 相似文献
888.
S. M. Salazar A. P. Castagnaro M. E. Arias N. Chalfoun U. Tonello J. C. Díaz Ricci 《European journal of plant pathology / European Foundation for Plant Pathology》2007,117(2):109-122
In the strawberry crop area of Tucumán (north-west Argentina) the three species of Colletotrichum causing anthracnose disease (C. acutatum, C. fragariae and C. gloeosporioides) were detected. Among all isolates characterized, one of them identified as C. acutatum (M11) and another as C. fragariae (F7) were selected due to their conspicuous interaction with the strawberry cultivar Pájaro. Whereas isolate M11 produced
a strong compatible interaction in cv. Pájaro with clear disease symptoms (DSR = 5.0), the isolate F7 brought about a typical
incompatible interaction (DSR = 1.0). When plants of cv. Pájaro were inoculated with F7 prior to the inoculation with M11,
the former avirulent strain prevented the growth of the latter virulent pathogen. Experimental evidence indicated that the
time elapsed between the first inoculation with the avirulent pathogen and the second inoculation with the virulent one was
crucial to inhibit the growth of the latter. The growth of F7 on the plant without provoking damage and the fact that there
was no in vitro antagonistic effect between the pathogens, suggests that the avirulent strain triggers a plant defensive response against
M11. The defense response was further confirmed by the detection of an early oxidative burst occurring within 4 h after the
first inoculation and by the observation of anatomical changes associated with defense mechanisms that lasted 50 days after
the inoculation with F7. Results obtained support the hypothesis that the plant resistance against the virulent strain M11
is elicited by one or more diffusible(s) compound(s) produced by the avirulent strain F7. 相似文献
889.
890.
Multiscale sources of variation in ecological variables: modeling spatial dispersion,elaborating sampling designs 总被引:6,自引:0,他引:6
Detection of structured spatial variation and identification of spatial scales are important aspects of ecological studies. Spatial structures can correspond to physical features of the environment or to intrinsic characteristics of ecological processes and phenomena. Spatial variability has been approached through several techniques such as classical analysis of variance, or the calculation of fractal dimensions, correlograms or variograms. Under certain assumptions, these techniques are all closely related to one another and represent equivalent tools to characterize spatial structures.Our perception of ecological variables and processes depends on the scale at which variables are measured. We propose simple nested sampling designs enabling the detection of a wide range of spatial structures that show the relationships among nested spatial scales. When it is known that the phenomenon under study is structured as a nested series of spatial scales, this provides useful information to estimate suitable sampling intervals, which are essential to establish the relationships between spatial patterns and ecological phenomena. The use of nested sampling designs helps in choosing the most suitable solutions to reduce the amount of random variation resulting from a survey. These designs are obtained by increasing the sampling intensity to detect a wider spectrum of frequencies, or by revisiting the sampling technique to select more representative sampling units. 相似文献