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1.
Julien Cucherousset Line E. Sundt-Hansen Mathieu Buoro Libor Závorka Rémy Lassus Knut A. E. Bækkelie Ian A. Fleming Björn Thrandur Björnsson Jörgen I. Johnsson Kjetil Hindar 《Journal of fish biology》2021,99(6):1978-1989
Use of fast-growing domesticated and/or genetically modified strains of fish is becoming increasingly common in aquaculture, increasing the likelihood of deliberate or accidental introductions into the wild. To date, their ecological impacts on ecosystems remain to be quantified. Here, using a controlled phenotype manipulation by implanting growth hormone in juvenile Atlantic salmon (Salmo salar), we found that growth-enhanced fish display changes in several phenotypic traits known to be important for ecosystem functioning, such as habitat use, morphology and excretion rate. Furthermore, these phenotypic changes were associated with significant impacts on the invertebrate community and key stream ecosystem functions such as primary production and leaf-litter decomposition. These findings provide novel evidence that introductions of growth-enhanced fish into the wild can affect the functioning of natural ecosystems and represent a form of intraspecific invasion. Consequently, environmental impact assessments of growth-enhanced organisms need to explicitly consider ecosystem-level effects. 相似文献
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Nataliia Rudenko Maryna Golovchenko Václav H?nig Nadja Mallátová Lenka Krbková Peter Mikulá?ek Natalia Fedorova Natalia M. Belfiore Libor Grubhoffer Robert S. Lane James H. Oliver Jr. 《Applied and environmental microbiology》2013,79(5):1444-1453
Comparative analysis of ospC genes from 127 Borrelia burgdorferi sensu stricto strains collected in European and North American regions where Lyme disease is endemic and where it is not endemic revealed a close relatedness of geographically distinct populations. ospC alleles A, B, and L were detected on both continents in vectors and hosts, including humans. Six ospC alleles, A, B, L, Q, R, and V, were prevalent in Europe; 4 of them were detected in samples of human origin. Ten ospC alleles, A, B, D, E3, F, G, H, H3, I3, and M, were identified in the far-western United States. Four ospC alleles, B, G, H, and L, were abundant in the southeastern United States. Here we present the first expanded analysis of ospC alleles of B. burgdorferi strains from the southeastern United States with respect to their relatedness to strains from other North American and European localities. We demonstrate that ospC genotypes commonly associated with human Lyme disease in European and North American regions where the disease is endemic were detected in B. burgdorferi strains isolated from the non-human-biting tick Ixodes affinis and rodent hosts in the southeastern United States. We discovered that some ospC alleles previously known only from Europe are widely distributed in the southeastern United States, a finding that confirms the hypothesis of transoceanic migration of Borrelia species. 相似文献
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Nataliia Rudenko Maryna Golovchenko Libor Grubhoffer James H. Oliver Jr. 《Applied and environmental microbiology》2013,79(4):1403-1406
The rare ospC allele L was detected in 30% of Borrelia burgdorferi sensu stricto strains cultured from a tick species, Ixodes affinis, and two rodent host species, Peromyscus gossypinus and Sigmodon hispidus, collected in a coastal plain area of Georgia and South Carolina, in the southeastern United States. 相似文献
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Do individual Activity Patterns of Brown Trout (Salmo trutta) alter the Exposure to Parasitic Freshwater Pearl Mussel (Margaritifera margaritifera) Larvae? 下载免费PDF全文
Niklas Wengström Fredrik Wahlqvist Joacim Näslund David Aldvén Libor Závorka Martin E Österling Johan Höjesjö 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(9):769-778
The hypothesis that interindividual differences in the activity of brown trout alter the exposure to parasitic freshwater pearl mussel glochidia was tested in a Swedish stream. Wild yearling brown trout (N = 103) were caught, individually tagged for identification and scored for open‐field activity during standardized laboratory tests in June. Fifty gravid freshwater pearl mussels were relocated to the stream, where after the trout were released back into the stream. The fish were recaptured in October (N = 35), checked for glochidia encystment (infested individuals: n = 6) and re‐scored for open‐field activity traits. Swimming velocity during the test was higher in fish infected with glochidia, suggesting that high activity could increase their exposure to glochidia. Potentially, as metabolism rate and ventilation rate typically increase with activity, elevated activity may lead to an increased likelihood of glochidia passing over the gills. This novel finding suggests that glochidia infestation is non‐random and that the behaviour of the host fish can influence the likelihood of glochidia infestation. 相似文献
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Karhánek D Kacer P Kuzma M Splíchalová J Cervený L 《Journal of molecular modeling》2007,13(9):1009-1016
Theoretical investigation of Pt(0)-olefin organometallic complexes containing tertiary phosphine ligands was focused on the
strength of platinum-olefin electronic interaction. DFT theoretical study of electronic effects in a substantial number of
ethylene derivatives was evaluated in terms of the Pt-olefin binding energy using MP2 correlation theory. Organometallics
bearing coordinated olefins with general formula (R1R2C = CR3R4)Pt(PH3)2 [R = various substituents] had been selected, including olefins containing both electron-donor substituents as well as electron-withdrawing
groups. The stability of the corresponding complexes increases with a strengthening electron-withdrawal ability of the olefin
substituents.
Figure Representation of (CH2 = CHR)Pt(PPh3)2 and the stability chart 相似文献
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A rapid and simple method has been developed for the electroporation of Clostridium perfringens with plasmid DNA. The new improvements, harvesting cells early in the logarithmic stage of growth, keeping the cells at room temperature and the absence of post-shock incubation on ice increased transformation efficiency by one order of magnitude. 相似文献
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Marili Laas Kalev Adamson Irene Barnes Josef Janouek Martin S. Mullett Katarína Adam
íkov Mitsuteru Akiba Ludwig Beenken Helena Braganca Timur S. Bulgakov Paolo Capretti Thomas Cech Michelle Cleary Rasmus Enderle Luisa Ghelardini Libor Jankovský Svetlana Markovskaja Iryna Matsiakh Joana B. Meyer Funda Oskay Barbara Pikur Kristina Raitelaityt Duan Sadikovi Rein Drenkhan 《Molecular Plant Pathology》2022,23(11):1620
Lecanosticta acicola is a pine needle pathogen causing brown spot needle blight that results in premature needle shedding with considerable damage described in North America, Europe, and Asia. Microsatellite and mating type markers were used to study the population genetics, migration history, and reproduction mode of the pathogen, based on a collection of 650 isolates from 27 countries and 26 hosts across the range of L. acicola. The presence of L. acicola in Georgia was confirmed in this study. Migration analyses indicate there have been several introduction events from North America into Europe. However, some of the source populations still appear to remain unknown. The populations in Croatia and western Asia appear to originate from genetically similar populations in North America. Intercontinental movement of the pathogen was reflected in an identical haplotype occurring on two continents, in North America (Canada) and Europe (Germany). Several shared haplotypes between European populations further suggests more local pathogen movement between countries. Moreover, migration analyses indicate that the populations in northern Europe originate from more established populations in central Europe. Overall, the highest genetic diversity was observed in south‐eastern USA. In Europe, the highest diversity was observed in France, where the presence of both known pathogen lineages was recorded. Less than half of the observed populations contained mating types in equal proportions. Although there is evidence of some sexual reproduction taking place, the pathogen spreads predominantly asexually and through anthropogenic activity. 相似文献