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Until recently, the advancement of the conservation plan of the critically endangered European sturgeon (Acipenser sturio) was limited since the attempts to reproduce fish of the ex situ stock were not very successful. From 2007 to 2010, 32 females reached maturity but reproduction trials provided limited numbers of individuals. From 2011, the situation has evolved positively. In 2011 the progenies of five out of nine females were obtained: a total of about 270,000 larvae. In 2012 and 2013, the results were even better with respectively 830,000 and 530,000 larvae, obtained from 16 out of 25 hormonally stimulated females. That success was probably linked to a combination of several improvements: (i) diet in quality and quantity ensuring a normal gonad development, (ii) control of the environment (i.e., salinity and temperature), (iii) more extended monitoring of oocytes’ morphometric characteristics and physiological state of ovarian follicles, (iv) new protocol of individual hormonal stimulation. Most of the juveniles produced were released in nature to support the remaining population. The others were included in the ex situ stock.  相似文献   

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Representative specimens of the EuropeanGladiolus species (excl.G. palustris) were used to study variability and relationships. 25 characters were measured for cluster, principal component and Wells hybrid analyses (Figs. 1–3). Three (with PCA) respective five (cluster analysis) main groups are revealed. Bulb characteristics appear to be very useful for indentification. The subspecific status ofG. communis subsp.byzantinus is confirmed. Hybrids of four different parental combinations were detected in our collection. Most species include polyploid series. Partly 3x, 4x, 6x, 8x, 12x and aneuploid cytotypes but no diploids were found. Polyploids as pioneers and hybridization of sympatric species are apparently linked to migrations during the glacial periods.  相似文献   

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New Late Permian fishes combining features characteristic of several classes are analyzed and redescribed. They were assigned to the family Discordichthyidae of the order Discordichthyiformes comprising three genera and four species: Mutovinia stella Minich, Geryonichthys longus A. Minich, G. burchardi A. Minich, and Discordichthys spinifer A. Minich (Minikh, 1998). A new species, Mutovinia sennikovi sp. nov., is described. Due to rapid evolutionary replacement, discordichthyids are rather useful stratigraphically. The photographs of the skeleton and membrane bones of these fishes are published for the first time.  相似文献   

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The European Bioinformatics Institute (EBI) databases.   总被引:5,自引:2,他引:3       下载免费PDF全文
The European Bioinformatics Institute (EBI) maintains and distributes the EMBL Nucleotide Sequence database, Europe's primary nucleotide sequence data resource. The EBI also maintains and distributes the SWISS-PROT Protein Sequence database, in collaboration with Amos Bairoch of the University of Geneva. Over fifty additional specialist molecular biology databases, as well as software and documentation of interest to molecular biologists are available. The EBI network services include database searching and sequence similarity searching facilities.  相似文献   

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The European Bioinformatics Institute (EBI) databases.   总被引:4,自引:3,他引:1       下载免费PDF全文
This paper describes the databases and services of the European Bioinformatics Institute (EBI). In collaboration with DDBJ and GenBank/NCBI, the EBI maintains and distributes the EMBL Nucleotide Sequence Database, Europe's primary nucleotide sequence data resource. The EBI also maintains and distributes the SWISS-PROT Protein Sequence Database, in collaboration with Amos Bairoch of the University of Geneva. Over thirty additional specialist molecular biology databases, as well as software and documentation of interest to molecular biologists, are also available. The EBI network services include database searching, entry retrieval, and sequence similarity searching facilities.  相似文献   

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We describe a new method for the sex determination of tissue originating from Oryctolagus cuniculus (European rabbit), Lepus europaeus (European brown hare) and Lepus timidus (mountain hare) based on PCR-RFLP analysis of point mutations that differentiate the ZFX and ZFY gene sequences. Among several applications, this PCR-RFLP method could be used to investigate gender ratio and evaluate the population dynamics of these species using samples collected when sex cannot be identified.  相似文献   

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The oceans and coastal seas provide mankind with many benefits including food for around a third of the global population, the air that we breathe and our climate system which enables habitation of much of the planet. However, the converse is that generation of natural events (such as hurricanes, severe storms and tsunamis) can have devastating impacts on coastal populations, while pollution of the seas by pathogens and toxic waste can cause illness and death in humans and animals. Harmful effects from biogenic toxins produced by algal blooms (HABs) and from the pathogens associated with microbial pollution are also a health hazard in seafood and from direct contact with water. The overall global burden of human disease caused by sewage pollution of coastal waters has been estimated at 4 million lost person-years annually. Finally, the impacts of all of these issues will be exacerbated by climate change. A holistic systems approach is needed. It must consider whole ecosystems, and their sustainability, such as integrated coastal zone management, is necessary to address the highly interconnected scientific challenges of increased human population pressure, pollution and over-exploitation of food (and other) resources as drivers of adverse ecological, social and economic impacts. There is also an urgent and critical requirement for effective and integrated public health solutions to be developed through the formulation of politically and environmentally meaningful policies. The research community required to address “Oceans & Human Health” in Europe is currently very fragmented, and recognition by policy makers of some of the problems, outlined in the list of challenges above, is limited. Nevertheless, relevant key policy issues for governments worldwide include the reduction of the burden of disease (including the early detection of emerging pathogens and other threats) and improving the quality of the global environment. Failure to effectively address these issues will impact adversely on efforts to alleviate poverty, sustain the availability of environmental goods and services and improve health and social and economic stability; and thus, will impinge on many policy decisions, both nationally and internationally. Knowledge exchange (KE) will be a key element of any ensuing research. KE will facilitate the integration of biological, medical, epidemiological, social and economic disciplines, as well as the emergence of synergies between seemingly unconnected areas of science and socio-economic issues, and will help to leverage knowledge transfer across the European Union (EU) and beyond. An integrated interdisciplinary systems approach is an effective way to bring together the appropriate groups of scientists, social scientists, economists, industry and other stakeholders with the policy formulators in order to address the complexities of interfacial problems in the area of environment and human health. The Marine Board of the European Science Foundation Working Group on “Oceans and Human Health” has been charged with developing a position paper on this topic with a view to identifying the scientific, social and economic challenges and making recommendations to the EU on policy-relevant research and development activities in this arena. This paper includes the background to health-related issues linked to the coastal environment and highlights the main arguments for an ecosystem-based whole systems approach.  相似文献   

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Beetle remains from the Triassic Khey-Yaga locality, Nenets National District, Korotaikha Basin, Nyadeita Formation, Olenekian-Anisian are described. Only isolated elytra have been found. Tetracoleus tshalyshevi gen. et sp. nov. and T. minimus sp. nov. are described and assigned to Tricoleidae, and six new species are described in formal taxa. Tetracoleus is close to Permian tricoleids just found in the Newcastle Group of Australia and the Vyatkian Aristovo locality of northern European Russia. The composition of elytra in the locality is closer to that of Lower Triassic localities than other Middle Triassic localities and characterizes the beginning of a recovery after the Permian-Triassic ecological crisis. Longxianocupes Hong in Liu, Liu et Hong, 1985 is shown to be a junior synonym of Sogdelytron Ponomarenko, 1969. The species Palademosyne ovum Ponomarenko, 2004, P. elongatum Ponomarenko, 2004, and P. latum Ponomarenko, 2004 are transferred to the genus Pseudochrysomelites Handlirsch, 1906.  相似文献   

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Summary Gap-detection thresholds were determined for single units in the cochlear ganglion and in auditory nerve fibres of the starling from responses to two broad-band noise bursts separated by a temporal gap of between 0.4 and 204.8 ms. All 35 units showed a threshold within the range of gap sizes tested. The median minimum-detectable gap was 12.8 ms with the minimum being 1.6 ms. A multiple regression analysis revealed that the size of the minimum-detectable gap was not significantly correlated with the neuron's CF, with its sharpness of tuning as given by its bandwidth 10 dB above threshold, or with its Q10dB value. Only the level of stimulation above the neuron's threshold showed a significant negative correlation with the size of the minimum-detectable gap. These results are discussed with respect to theoretical considerations of limits posed on temporal resolution by the characteristics of peripheral filters. These findings are also discussed in the context of the coding of gaps at different levels of the starling's auditory system and in relation to psychoacoustic results in the starling on gap detection and time resolution described by temporal modulation transfer functions.  相似文献   

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The European light dosimeter network of over 40 stations has been established in Europe and other continents equipped with three-channel filter dosimeters to measure solar radiation in three channels, UV-B (280–315 nm), UV-A (315–400 nm) and photosynthetically active radiation (PAR). The recorded data have been evaluated, and the monthly doses in all three channels show a strong latitudinal dependence from northern Sweden to the Canary Islands. There are a few remarkable exceptions such as the data recorded at the high mountain station on the Zugspitze (German Alps) and unequal doses at stations at comparable latitudes which indicate the impact of local weather conditions and mean sunshine hours. While generally peak values are recorded in the months of June and July, the UV-B maxima are shifted later into the year, which is due to the antagonistic functions of decreasing solar angles and increasing transparency of the atmosphere as the total column ozone decreases in the second half of the year for the Northern Hemisphere. This is supported by comparison with modelled total column ozone and satellite-based measurements. Also the ratios of UV-B:UV-A and UV-B:PAR as well as UV-A:PAR peak during the summer months, with the exception of the northernmost station at Abisko (north Sweden) where the UV-A:PAR ratio peaks in the winter months which is due to the specific photoclimatic conditions north of the polar circle. The penetration of solar radiation into the water column was found to strongly depend on the transparency of the water column. In Gran Canaria more than 10% of the surface UV-B penetrated to 4–5 m depth. The path of the solar eclipse on 11 August 1999 could be followed in several stations with different degrees of occlusion of the sun disk. Received in revised form: 12 May 2000 Electronic Publication  相似文献   

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