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The mussel Sinanodonta woodiana (Lea, 1834), which is an alien species to European malacofauna, was introduced in Europe in the early 1960s (Romania, Hungary) from Asia along with stocking material of herbivorous fishes. Subsequently, the species expanded to Austria, France, Yugoslavia, Poland, Slovakia, the Czech Republic, and Germany. For over a dozen years, the only site in Poland where this mussel was documented was the heated lake system near Konin. In 2003, Sinanodonta woodiana was found in the warm water canal of the Szczecin power plant, and from 2002 to 2006 it was observed in basins with natural thermal regime, including fish ponds in Great Poland and the Warta-Gop³o Canal near Konin. In recent years, the species has also been recorded from the eastern and southern European countries through which the Danube River flows.
In the mid 1980s, the Chinese clam Sinanodonta woodiana (Lea, 1834) from SE. Asia was accidentally introduced in the Konin heated lake system (central Poland) from Hungary, along with fish stocking material. Currently, it inhabits abundantly the littoral zones of the five lakes that comprise the system, the initial cooling basin, and most of the associated intake and discharge canals. The considerable heterogeneity of its habitats in the system affects the morphological variation of its shells. The shell morphology, size, colour and growth rate are shaped by environmental factors, of which temperature, water flow intensity, and substrate type are the most important. The largest and heaviest specimens were found in the warmest habitats with the fastest water flow. Specimens with shells up to 160 mm long constituted most of the population, while in moderately heated areas the length was upto 125 mm, and in the coolest areas – 115 mm. The maximum individual weight was 900 g.
The samples of water, fish and of the sea bottom residuals taken in years 1982, 1985, 1987 and 1988 from the Baltic were assessed for the presence of Pseudomonas spp. and gram-negative non-fermentative bacterial strains. A total of 361 strains was isolated from fish, i.e. 224 strains from diseased fish, 137 from normal fish and in addition 176 from water and 214 from residuals of the sea bottom. A total of 751 strains was examined biochemically. From fish most often there were isolated: Ps. aeruginosa (30 strains), Ps. fluorescens (21), Ps. alcaligenes (18), Ps. pseudoalcaligenes (7), Ps. testosteroni (4), Ps. cepacia (1), A. calcoaceticus lwoffi (6) and A. calcoaceticus alcaligenes (4). From water and residuals of the sea bottom apart from the above baceria there were noted mostly Ps. putrefaciens (7 and 4 respectively), Ps. diminuta (7), Ps. stutzeri (3), Ps. vesicularis (3) and M. osloensis (8). It was found that the strains under study were identical or very similar to those isolated from human and animals.
In the mid 1980s the southeast Asian mussel Sinanodonta woodiana (Lea, 1834) was introduced into a lake system that is heated by power plant discharge waters (near Konin in central Poland) along with fish stocking material from Hungary. Currently, this species is abundant in the littoral zones of the five lakes in the system, the initial water cooling reservoir, as well as most of the intake and discharge canals. This species prefers a habitat with a moderate water flow rate (0.05–0.30 m s⁻¹) and a relatively high water temperature (10–30ºC), and it usually forms aggregations. It avoids strong water turbulence and coarse sediments, although it does occur sporadically in the direct vicinity of water intake pumps and water discharge as well as on gravel substrates. The largest aggregation of Sinanodonta woodiana occurred at depths of 1.5–2.5 m. The highest number and biomass of this species was noted in the discharge canal and initial cooling reservoir where the water was the warmest. Population density sometimes exceeded 60 ind m⁻², while mussel biomass (including the shell) reached as much as 25 kg m⁻².
This review gives a short account of selected aspects of oligoribonucleotide synthesis via the H-phosphonate method. It includes: (i) recent methods for the preparation of suitably protected ribonucleoside 3'-H-phosphonates (the phosphonylation step), (ii) some chemical and stereochemical features of the formation of H-phosphonate internucleosidic linkages, and (iii) stereoselective synthesis of oligoribonucleoside phosphorothioates using chemo-enzymatic approach.
The Chinese mussel Anodonta woodiana was accidentally introduced into the heated Konin lakes system in the mid 1980's. It inhabits the littoral of the five lakes of the complex, a preliminary cooling reservoir, and most of the discharge and inflow channels. It prefers habitats of an increased flow velocity and of rather high temperature. It has been found to be the dominant benthic species in most of the habitats. At times, its biomass exceeded 10 kg m⁻² , and it numbered more than 40 individuals per m².
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