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L.?-M.?HerborgEmail author S.?P.?Rushton A.?S.?Clare M.?G.?Bentley 《Biological invasions》2005,7(6):959-968
Owing to its catadromous lifestyle, the Chinese mitten crab, Eriocheir sinensis, allows comparison between a coastal and an inland biological invasion of the same species. Information about the distribution
of this species in the United Kingdom has been collected from sightings made by governmental agencies, The Natural History
Museum (London) collection, literature, and from the general public. This information indicated that the range of the species
has expanded since the species’ arrival in 1973. The spread has been most marked along the east coast northwards to the river
Tyne, on the south coast westwards to the river Teign. The expansion range was quantified and compared using geographic information
software, and then compared to recorded spread in Europe. Mitten crabs dispersed along the coast at an average rate of 78 km
per year (1976–1999), with a recent sharp increase to 448 km per year (1997–1999). These values are comparable with the historic
outbreak in continental Europe where the average rate of dispersion along the Baltic Sea coast (1928–1935) was 416 km per
year. Comparable figures for the North Sea coast (1923–1954) were 75 km per year with a peak of 168 km per year in 1927–1937.
The upstream spread along rivers in the United Kingdom was 16 km per year in 1973–1998 with a marked increase since 1995 to
49 km per year (1995–1998). These data, in combination with population data published for the river Thames, indicate that
the population has been increasing since the early 1990s, causing further range expansion into previously uninvaded river
systems. The comparison of the spreading behaviour of the ongoing invasion in the United Kingdom with the historic invasion
in northern Europe suggests that E. sinensis in future has the potential to establish itself in all major UK estuaries. 相似文献
123.
Tim?Lu Christine?M?Costello Peter?JP?Croucher Robert?H?sler Günther?Deuschl Stefan?SchreiberEmail author 《BMC bioinformatics》2005,6(1):37
Background
Normalization is the process of removing non-biological sources of variation between array experiments. Recent investigations of data in gene expression databases for varying organisms and tissues have shown that the majority of expressed genes exhibit a power-law distribution with an exponent close to -1 (i.e. obey Zipf's law). Based on the observation that our single channel and two channel microarray data sets also followed a power-law distribution, we were motivated to develop a normalization method based on this law, and examine how it compares with existing published techniques. A computationally simple and intuitively appealing technique based on this observation is presented. 相似文献124.
Engineering plants with increased disease resistance: how are we going to express it? 总被引:1,自引:0,他引:1
Precise control of transgene expression is pivotal to the engineering of plants with increased disease resistance. Many early attempts to boost disease resistance used constitutive overexpression of defence components but frequently this resulted in poor quality plants. It is now clear that the extensive cellular reprogramming associated with defence will reduce yields if uncontrolled defence reactions are activated in uninfected cells. Therefore, for many strategies pathogen-inducible promoters might be the most useful as they limit the cost of resistance by restricting expression to infection sites. Although progress to date has been hindered by a lack of suitable promoters, new research should reveal more potentially useful native promoters. Additionally, the first steps towards 'designer' synthetic promoters have proved encouraging. 相似文献
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