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1672. Alien fish species in the Czech Republic and their impact on the native fish fauna
- Creator:
- Lusk, Stanislav, Lusková, Věra, and Hanel, Lubomír
- Type:
- article and TEXT
- Subject:
- introduction, translocation, and invasion
- Language:
- English
- Description:
- Over the past 150 years, the waters of the Czech Republic were experimentally stocked or invaded by a total of 41 alien (non-native) fish species. The following species have become fully naturalized and produced self-sustained populations: Carassius gibelio, Pseudorasbora parva, Ameiurus nebulosus and Gasterosteus aculeatus, which produced stable populations in several spatially limited localities. In some cases Oncorhynchus mykiss, Salvelinus fontinalis and Coregonus maraena will produce instable temporary populations based on released material obtained from fish farms and ponds. The occurrence of the remaining acclimatized alien species (Coregonus peled, Ctenopharyngodon idella, Hypophthalmichthys molitrix, Aristichthys nobilis) in natural ecosystems and fishponds depends on stocking fish obtained from artificial spawning and cultures. The documented annual average production of alien species fit for human consumption amounts to around 2 000 tonnes, i.e. 8.2 % of the annual average production of marketable fish cultures in the Czech Republic. A significant negative impact of the introduced species on native ichthyofauna has been ascertained as regards its ecological, biological properties, biodiversity and health. Considered a typical invasive alien species, Carassius gibelio heavily depressed the occurrence and numbers of indigenous Carassius carassius populations and also contributed to the decreased numbers of Tinca tinca, Leucaspius delineatus and other native cyprinid fish. P. parva and A. nebulosus show a much weaker and limited impact. The introduction of C. idella was accompanied by the introduction of the tapeworm species, Bothriocephalus gowkongensis, which subsequently caused heavy losses in cultures of Cyprinus carpio. In 2008, Neogobius melanostomus was recorded for the first time in this country at the confluence of the Morava and Dyje rivers.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
1673. Alien flora of Europe: species diversity, temporal trends, geographical patterns and research needs
- Creator:
- Lambdon, Philip W., Pyšek, Petr, Basnou, Corina, Hejda, Martin, Arianoutsou, Margarita, Essl, Franz, Jarošík, Vojtěch, Pergl, Jan, Winter, Marten, Anastasiu, Paulina, Andriopoulos, Pavlos, Bazos, Ioannis, Brundu, Giuseppe, Celesti-Grapow, Laura, Chassot, Philippe, Delipetrou, Pinelopi, Josefsson, Melanie, Kark, Salit, Klotz, Stefan, Kokkoris, Yannis, Kühn, Ingolf, Marchante, Hélia, Perglová, Irena, Pino, Joan, Vilà, Montserrat, Zikos, Andreas, Roy, David, and Hulme, Philip E.
- Type:
- article and TEXT
- Subject:
- alien plants, biogeographical pattern, donor regions, Europe, habitat affinity, naturalization, neophytes, plant invasions, residence time, and temporal trends
- Language:
- English
- Description:
- The paper provides the first estimate of the composition and structure of alien plants occurring in the wild in the European continent, based on the results of the DAISIE project (2004–2008), funded by the 6th Framework Programme of the European Union and aimed at “creating an inventory of invasive species that threaten European terrestrial, freshwater and marine environments”. The plant section of the DAISIE database is based on national checklists from 48 European countries/regions and Israel; for many of them the data were compiled during the project and for some countries DAISIE collected the first comprehensive checklists of alien species, based on primary data (e.g., Cyprus, Greece, F. Y. R. O. Macedonia, Slovenia, Ukraine). In total, the database contains records of 5789 alien plant species in Europe (including those native to a part of Europe but alien to another part), of which 2843 are alien to Europe (of extra-European origin). The research focus was on naturalized species; there are in total 3749 naturalized aliens in Europe, of which 1780 are alien to Europe. This represents a marked increase compared to 1568 alien species reported by a previous analysis of data in Flora Europaea (1964–1980). Casual aliens were marginally considered and are represented by 1507 species with European origins and 872 species whose native range falls outside Europe. The highest diversity of alien species is concentrated in industrialized countries with a tradition of good botanical recording or intensive recent research. The highest number of all alien species, regardless of status, is reported from Belgium (1969), the United Kingdom (1779) and Czech Republic (1378). The United Kingdom (857), Germany (450), Belgium (447) and Italy (440) are countries with the most naturalized neophytes. The number of naturalized neophytes in European countries is determined mainly by the interaction of temperature and precipitation; it increases with increasing precipitation but only in climatically warm and moderately warm regions. Of the nowadays naturalized neophytes alien to Europe, 50% arrived after 1899, 25% after 1962 and 10% after 1989. At present, approximately 6.2 new species, that are capable of naturalization, are arriving each year. Most alien species have relatively restricted European distributions; half of all naturalized species occur in four or fewer countries/regions, whereas 70% of non-naturalized species occur in only one region. Alien species are drawn from 213 families, dominated by large global plant families which have a weedy tendency and have undergone major radiations in temperate regions (Asteraceae, Poaceae, Rosaceae, Fabaceae, Brassicaceae). There are 1567 genera, which have alien members in European countries, the commonest being globally-diverse genera comprising mainly urban and agricultural weeds (e.g., Amaranthus, Chenopodium and Solanum) or cultivated for ornamental purposes (Cotoneaster, the genus richest in alien species). Only a few large genera which have successfully invaded (e.g., Oenothera, Oxalis, Panicum, Helianthus) are predominantly of non-European origin. Conyza canadensis, Helianthus tuberosus and Robinia pseudoacacia are most widely distributed alien species. Of all naturalized aliens present in Europe, 64.1% occur in industrial habitats and 58.5% on arable land and in parks and gardens. Grasslands and woodlands are also highly invaded, with 37.4 and 31.5%, respectively, of all naturalized aliens in Europe present in these habitats. Mires, bogs and fens are least invaded; only approximately 10% of aliens in Europe occur there. Intentional introductions to Europe (62.8% of the total number of naturalized aliens) prevail over unintentional (37.2%). Ornamental and horticultural introductions escaped from cultivation account for the highest number of species, 52.2% of the total. Among unintentional introductions, contaminants of seed, mineral materials and other commodities are responsible for 1091 alien species introductions to Europe (76.6% of all species introduced unintentionally) and 363 species are assumed to have arrived as stowaways (directly associated with human transport but arriving independently of commodity). Most aliens in Europe have a native range in the same continent (28.6% of all donor region records are from another part of Europe where the plant is native); in terms of species numbers the contribution of Europe as a region of origin is 53.2%. Considering aliens to Europe separately, 45.8% of species have their native distribution in North and South America, 45.9% in Asia, 20.7% in Africa and 5.3% in Australasia. Based on species composition, European alien flora can be classified into five major groups: (1) north-western, comprising Scandinavia and the UK; (2) west-central, extending from Belgium and the Netherlands to Germany and Switzerland; (3) Baltic, including only the former Soviet Baltic states; (4) east-central, comprizing the remainder of central and eastern Europe; (5) southern, covering the entire Mediterranean region. The clustering patterns cut across some European bioclimatic zones; cultural factors such as regional trade links and traditional local preferences for crop, forestry and ornamental species are also important by influencing the introduced species pool. Finally, the paper evaluates a state of the art in the field of plant invasions in Europe, points to research gaps and outlines avenues of further research towards documenting alien plant invasions in Europe. The data are of varying quality and need to be further assessed with respect to the invasion status and residence time of the species included. This concerns especially the naturalized/casual status; so far, this information is available comprehensively for only 19 countries/regions of the 49 considered. Collating an integrated database on the alien flora of Europe can form a principal contribution to developing a European-wide management strategy of alien species.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
1674. Alien invasive fish species in Polish waters
- Creator:
- Grabowska, Joanna, Kotusz, Jan, and Witkowski, Andrzej
- Type:
- article and TEXT
- Subject:
- non-indigenous species, introduction, invasion, and impact of exotic species
- Language:
- English
- Description:
- For the last 800 years, 35 alien fish species have been introduced, mainly intentionally, in Polish inland waters. The paper reviews the present state of alien fish fauna in Poland, with special attention paid to those considered to be invasive. Till now 26 species have been reported as naturalized, acclimatized or casual and it means that 34% of fish fauna are non-indigenous species. The majority came from North America, Eastern Asia and Siberia or different regions of Europe. More than 65 % of all introductions took place in the last 60 years. After the World War II the rapid expansion was noted specially for brown bullhead, Ameiurus nebulosus and gibel, Carassius gibelio. In the recent decade similar explosive spread has been observed for three Neogobius species (round goby, N. melanostomus, racer goby, N. gymnotrachelus, monkey goby, N. fluviatilis), Amur sleeper, Perccottus glenii and topmouth gudgeon, Pseudorasbora parva. The occurrence of introduced fish species resulted in several negative changes in aquatic environments. Some of them are as follows: hybridisation with native species, destruction of spawning grounds and habitats for many freshwater organisms, decrease of native fish reproduction success due to predation on eggs and offspring and finally the aliens might be vectors for parasites and diseases.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
1675. Alien vascular plants recorded from the Barentsburg and Pyramiden settlements, Svalbard
- Creator:
- Liška , Jiří and Soldán , Zdeněk
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- adventive, allochtonous, Arctic, flora, introduced, non-indigenous, plant invasions, Spitsbergen, and Svalbard
- Language:
- English
- Description:
- A list of alien plant species recorded from Svalbard in the summer of 1988 is presented. Two localities, the Russian settlements of Barentsburg and Pyramiden on the Isfjorden, Spitsbergen, were studied. Prior to this study, almost 60 alien species were recorded from Svalbard by other investigators. During the research reported here, 44 taxa were found, 14 of which are new records for the Svalbard archipelago. Six species are considered to be possibly naturalized; however, it is difficult to assess their naturalization status because of the severity of the climate in the study area. A complete list of species is presented, with information on height and phenological stage of particular specimens. Most of the alien plants recorded at the two settlements belong to the family Brassicaceae.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1676. Alkaline phosphatase activity of duodenal enterocytes after neonatal administration of monosodium glutamate to rats
- Creator:
- Mozeš, Š., Ľudovít Lenhardt, and Martinková, A.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, obezita, obesity, alkaline phosphatase activity, duodenal enterocytes, monosodium glutamate, rat, 14, and 612
- Language:
- English
- Description:
- In the present work neonatal male and female Wistar rats were treated intraperitoneally with monosodium glutamate (MSG 2 mg/kg b.w.) or saline (controls) daily for 4 day after birth. At the age of 30 and 80 days, the alkaline phosphatase activity (AP) in the brush border of individual enterocytes, the body fat content and Lee´s index of obesity were analyzed. Microdensitometrical quantification of AP was significantly increased on day 30 in males (P<0.01) and on day 80 in MSG-treated male and female rats (P<0.001) as compared to the controls. MSG administration also increased the body fat weight and the obesity index significantly (P<0.001) in 80-day-old animals, but was without any significant effect on their food intake. Our results showed that a) neonatal MSG-treatment may significantly change the intestinal function and b) the investigation of the intestinal enzyme activities may be important in further studies on MSG-induced and other forms of obesity., Š. Mozeš, Ľ. Lenhardt, A. Martinková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1677. Alkaline phosphatase as marker of Schistosoma monsoni egg viability
- Creator:
- Giboda, M. and Žďárská, Z.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Schistosoma mansoni, eggs, viability, and alkaline phosphalase
- Language:
- English
- Description:
- A reliable assessment of the viability of schistosome eggs trapped in host tissues is difficult. The use of a coupling azo dye method for the detection of alkaline phosphatase (A1P) in Schistosoma mansoni ova was found to be a specific and sensitive method for differentiating between viable and dead eggs, and can be used in both immature and mature eggs. In fully developed miracidia within an egg, A1P activity was demonstrated in germ cells and in the sensory endings of the neural cells. The embryonating miracidia displayed A1P activity on the body surface and in von Lichienberg’s envelope. The alkaline phosphatase test for egg viability shows increased sensitivity when compared with the more conventional Oogram and Hatching tests.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1678. ALKB-8, a 2-oxoglutarate-dependent dioxygenase and S-adenosine methionine-dependent methyltransferase modulates metabolic events linked to lysosome-related organelles and aging in C. elegans
- Creator:
- Kollárová, J., Kostrouchová, M., and Benda, A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- lysosome-related organelle, methyltransferase, multifunctional enzyme, Nile red, oxidoreductase, RNA-binding, and transferase
- Language:
- English
- Description:
- ALKB-8 is a 2-oxoglutarate-dependent di-oxygenase homologous to bacterial AlkB, which oxidatively demethylates DNA substrates. The mammalian AlkB family contains AlkB homologues denominated ALKBH1 to 8 and FTO. The C. elegans genome includes five AlkB-related genes, homologues of ALKBH1, 4, 6, 7, and 8, but lacks homologues of ALKBH2, 3, and 5 and FTO. ALKBH8 orthologues differ from other AlkB family members by possessing an additional methyltransferase module and an RNA binding N-terminal module. The ALKBH8 methyltransferase domain generates the wobble nucleoside 5-methoxycarbonylmethyluridine from its precursor 5-carboxymethyluridine and its (R)- and (S)-5-methoxycarbonylhydroxymethyluridine hydroxylated forms in tRNAArgUCG and tRNAGlyUCC. The ALKBH8/ALKB-8 methyltransferase domain is highly similar to yeast TRM9, which selectively modulates translation of mRNAs enriched with AGA and GAA codons under both normal and stress conditions. In this report, we studied the role of alkb-8 in C. elegans. We show that downregulation of alkb-8increases detection of lysosome-related organelles visualized by Nile red in vivo. Reversely, forced expression of alkb-8 strongly decreases the detection of this compartment. In addition, overexpression of alkb-8 applied in a pulse during the L1 larval stage increases the C. elegans lifespan. and Corresponding author: Marta Kostrouchová
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1679. All about 1895: An Ideological Analysis of TV Serials from the Two Sides of the Taiwan Strait /
- Creator:
- Lee, Pei-Ling
- Type:
- text and studie
- Subject:
- Dějiny civilizace. Kulturní dějiny, vztahy čínsko-tchajwanské, ideologie, vztahy čínsko-japonské, seriály televizní, kinematografie, Tchaj-wan, světové dějiny od r. 1918 do současnosti, and divadlo, film, fotografie
- Language:
- English
- Rights:
- unknown
1680. All graphs in which each pair of distinct vertices has exactly two common neighbors
- Creator:
- Stevanović, Dragan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- graphs, adjacency matrix, eigenvalues of a graph, and common neighbours
- Language:
- English
- Description:
- We find all connected graphs in which any two distinct vertices have exactly two common neighbors, thus solving a problem by B. Zelinka.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public