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In 2001 the European Register of Marine Species 1.0 was published (Costello et al. 2001 and http://erms.biol.soton.ac.uk/, and latterly: http://www.marbef.org/data/stats.php) [Costello MJ, Emblow C, White R, 2001. European register of marine species: a check list of the marine species in Europe and a bibliography of guides to their identification. Collection Patrimoines Naturels50, 463p.]. The lists of species (from fungi to mammals) were published as part of a European Union Concerted action project (funded by the European Union Marine Science and Technology (MAST) research programme) and the updated version (ERMS 2) is EU-funded through the Marine Biodiversity and Ecosystem Functioning (MARBEF) Framework project 6 Network of Excellence. Among these lists, a list of the fungi isolated and identified from coastal and marine ecosystems in Europe was included (Clipson et al. 2001) [Clipson NJW, Landy ET, Otte ML, 2001. Fungi. In@ Costelloe MJ, Emblow C, White R (eds), European register of marine species: a check-list of the marine species in Europe and a bibliography of guides to their identification. Collection Patrimoines Naturels50: 15-19.]. This article deals with the results of compiling a new taxonomically correct and complete list of all fungi that have been reported occurring in European marine waters.  相似文献   

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Parahupehsuchus longus is a new species of marine reptile from the Lower Triassic of Yuan’an County, Hubei Province, China. It is unique among vertebrates for having a body wall that is completely surrounded by a bony tube, about 50 cm long and 6.5 cm deep, comprising overlapping ribs and gastralia. This tube and bony ossicles on the back are best interpreted as anti-predatory features, suggesting that there was predation pressure upon marine tetrapods in the Early Triassic. There is at least one sauropterygian that is sufficiently large to feed on Parahupehsuchus in the Nanzhang-Yuan’an fauna, together with six more species of potential prey marine reptiles with various degrees of body protection. Modern predators of marine tetrapods belong to the highest trophic levels in the marine ecosystem but such predators did not always exist through geologic time. The indication of marine-tetrapod feeding in the Nanzhang-Yuan’an fauna suggests that such a trophic level emerged for the first time in the Early Triassic. The recovery from the end-Permian extinction probably proceeded faster than traditionally thought for marine predators. Parahupehsuchus has superficially turtle-like features, namely expanded ribs without intercostal space, very short transverse processes, and a dorsal outgrowth from the neural spine. However, these features are structurally different from their turtle counterparts. Phylogeny suggests that they are convergent with the condition in turtles, which has a fundamentally different body plan that involves the folding of the body wall. Expanded ribs without intercostal space evolved at least twice and probably even more among reptiles.  相似文献   

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In recent years conservationist NGOs, policy makers, and scientists in the tropics have expressed a fascination with marine protected areas for simultaneously achieving conservation goals and economic development. Despite their popularity, MPAs often encounter serious implementation challenges due to, at least to some extent, our limited understanding of MPA processes as influenced by neoliberal ideology and practice. By resituating MPAs in debates of neoliberal conservation, this study aims to examine social and economic changes that MPAs bring about in fishing communities. Taking a fishing village in the Philippines as a case study, it shows technocratic solution seeking led to further marginalization of small-scale fishers through unequal distribution of benefits and burdens. Here it is argued that MPAs are prone to exclusionist processes of redefining the value and legitimate users of marine resources, which further limits the opportunities for small-scale fishers to participate meaningfully in resource governance.  相似文献   

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The biotransformation reactions of α-bromoacetophenone (1), p-bromo-α-bromoacetophenone (2), and p-nitro-α-bromoacetophenone (3) by whole cells of the marine fungus Aspergillus sydowii Ce19 have been investigated. Fungal cells that had been grown in artificial sea water medium containing a high concentration of chloride ions (1.20 M) catalysed the biotransformation of 1 to 2-bromo-1-phenylethanol 4 (56%), together with the α-chlorohydrin 7 (9%), 1-phenylethan-1,2-diol 9 (26%), acetophenone 10 (4%) and phenylethanol 11 (5%) identified by GC-MS analysis. In addition, it was observed that the enzymatic reaction was accompanied by the spontaneous debromination of 1 to yield α-chloroacetophenone 5 (9%) and α-hydroxyacetophenone 6 (18%) identified by GC-FID analysis. When 2 and 3 were employed as substrates, various biotransformation products were detected but the formation of halohydrins was not observed. It is concluded that marine fungus A. sydowii Ce19 presents potential for the biotransformations of bromoacetophenone derivatives.  相似文献   

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In 1993, about 52% of the 433 698 tons of thetotal US aquaculture production came from theproduction of freshwater catfish. Excludingsalmonid culture, the percentage of marine finfishculture in total aquaculture production in the UShas been negligible. Commercial scale production ofmarine finfish in hatcheries is very limited in theUS.Studies on eggs and larvae of marine finfishspecies in the US have stemmed from theconsideration of fisheries management rather thanaquaculture. Most of the marine finfish larvaeproduced in the laboratory has been for the purposeof providing materials for other academic relatedstudies. Results of these studies can be applied inthe development of marine finfish hatcherytechnology. Hatchery technology for several marinefinfish species has been developed for stockenhancement, technology transfer and aquaculture. This paper reviews the current hatchery technologyof striped mullet (Mugil cephalus), dolphinfish (Coryphaena hippurus), red drum (Sciaenops ocellatus), and other potentialaquaculture species.  相似文献   

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The remarkable success of Escherichia coli as a model organism in molecular genetics was dependent, among other things, on its susceptibility to genetic manipulation. Many versatile and sophisticated genetic tools for molecular biology studies are derived from bacteriophage λ. However, this bacteriophage is specific for E. coli, and thus λ-based techniques have been restricted to this bacterium. Plasmids expressing the E. coli gene coding for bacteriophage λ receptor were reported previously, and introduction of such plasmids into cells of some other bacteria made them sensitive to phage λ infection. However, we found that these systems were not efficient for Vibrio harveyi, one of the most frequently investigated species of marine bacteria. Here we describe construction of a broad-host-range plasmid expressing the lamB gene. Introduction of this plasmid to V. harveyi cells and expression of lamB made this strain susceptible to bacteriophage λ adsorption and λ DNA injection. Foreign genetic material could be introduced into cells of this strain using a cosmid vector. Received August 30, 2000; accepted January 30, 2001.  相似文献   

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The Mauensee section in the Molasse Basin (North Alpine Foreland Basin) of central Switzerland represents one of the best continuously exposed outcrops of the St. Gallen Formation of the Upper Marine Molasse. A similarly well-exposed section is at Schmiedrued, situated about 15 km to the north. Biostratigraphic analysis of mammal and fish faunas shows that both sections are of Early Karpatian age. Palaeoecological analysis of the biota indicates an oligohaline intercalation within the marine part of the sections. This is additionally confirmed by the oxygen isotopic compositions of fish otoliths from the Mauensee section. The overlying marine sequence may represent a fourth cycle in the St. Gallen Formation that might perhaps indicate a Karpatian transgression from the Mediterranean Sea, which has not previously been recognized. Biostratigraphic comparison shows that the sedimentation of the Upper Freshwater Molasse began at the base of the Karpatian in southwest Germany and eastern Switzerland, and in the Middle Karpatian in central Switzerland. The presence of a Karpatian marine sedimentation area in central Switzerland may explain that the terrestrial sedimentation of the Upper Freshwater Molasse began at such different times.This paper is dedicated to Erik Flügel. He always was open and attentive for all topics of palaeontology. We will never forget him.  相似文献   

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Lipid extraction of biomass prior to stable isotope analysis is known to cause variable changes in the stable nitrogen isotopic composition (δ15N) of residual biomass. However, the underlying factors causing these changes are not yet clear. Here we address this issue by comparing the δ15N of bulk and residual biomass of several marine animal tissues (fish, crab, cockle, oyster, and polychaete), as well as the δ15N of the extracted lipids. As observed previously, lipid extraction led to a variable offset in δ15N of biomass (differences ranging from -2.3 to +1.8 ‰). Importantly, the total lipid extract (TLE) was highly depleted in 15N compared to bulk biomass, and also highly variable (differences ranging from -14 to +0.7 ‰). The TLE consisted mainly of phosphatidylcholines, a group of lipids with one nitrogen atom in the headgroup. To elucidate the cause for the 15N-depletion in the TLE, the δ15N of amino acids was determined, including serine because it is one of the main sources of nitrogen to N-containing lipids. Serine δ15N values differed by -7 to +2 ‰ from bulk biomass δ15N, and correlated well with the 15N depletion in TLEs. On average, serine was less depleted (-3‰) than the TLE (-7 ‰), possibly due to fractionation during biosynthesis of N-containing headgroups, or that other nitrogen-containing compounds, such as urea and choline, or recycled nitrogen contribute to the nitrogen isotopic composition of the TLE. The depletion in 15N of the TLE relative to biomass increased with the trophic level of the organisms.  相似文献   

11.
New data on the taxonomic composition of the algal flora of the Late Viséan of the Moscow Basin are discussed based on newly collected material. The algal assemblage comprises 24 taxa, 14 taxa identified to species, nine identified to genus, and one taxon not positively identified. Representatives of the genera Anthracoporella, Anthracoporellopsis, Asphaltina, Asphaltinella, Asteroaoujgalia, and Zidella are recorded for the first time from the Upper Viséan of the Moscow Basin. The large geographic ranges of these benthic calcareous algae suggest a relatively free exchange of the floral elements of the Late Viséan Moscow Basin with the remote basins of North America and the Paleotethys in the Aleksinian and Mikhailovian time. The new data fill an important gap in the current state of knowledge of Late Viséan marine algae.  相似文献   

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Applied Microbiology and Biotechnology - Chitinolytic enzymes are capable to catalyze the chitin hydrolysis. Due to their biomedical and biotechnological applications, nowadays chitinolytic enzymes...  相似文献   

14.
Most fungal species from marine environments also live on land. It is not clear whether these fungi reach the sea from terrestrial sources as spores or other propagules, or if there are separate ecotypes that live and reproduce in the sea. The emergence of marine diseases has created an urgency to understand the distribution of these fungi. Aspergillus flavus is ubiquitous in both terrestrial and marine environments. This species is an opportunistic pathogen in many hosts, making it a good model to study the relationship between genetic diversity and specificity of marine fungi. In this study, an intraspecific phylogeny of A. flavus isolates based on Amplified Fragment Length Polymorphisms (AFLPs) was used to determine if terrestrial and marine isolates form discrete populations, and to determine if phylogeny predicts substratum specificity. Results suggest lack of population structure in A. flavus. All isolates may compose a single population, with no clade particular to marine environments.  相似文献   

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Planning for resilience is the focus of many marine conservation programs and initiatives. These efforts aim to inform conservation strategies for marine regions to ensure they have inbuilt capacity to retain biological diversity and ecological function in the face of global environmental change--particularly changes in climate and resource exploitation. In the absence of direct biological and ecological information for many marine species, scientists are increasingly using spatially-explicit, predictive-modeling approaches. Through the improved access to multibeam sonar and underwater video technology these models provide spatial predictions of the most suitable regions for an organism at resolutions previously not possible. However, sensible-looking, well-performing models can provide very different predictions of distribution depending on which occurrence dataset is used. To examine this, we construct species distribution models for nine temperate marine sedentary fishes for a 25.7 km(2) study region off the coast of southeastern Australia. We use generalized linear model (GLM), generalized additive model (GAM) and maximum entropy (MAXENT) to build models based on co-located occurrence datasets derived from two underwater video methods (i.e. baited and towed video) and fine-scale multibeam sonar based seafloor habitat variables. Overall, this study found that the choice of modeling approach did not considerably influence the prediction of distributions based on the same occurrence dataset. However, greater dissimilarity between model predictions was observed across the nine fish taxa when the two occurrence datasets were compared (relative to models based on the same dataset). Based on these results it is difficult to draw any general trends in regards to which video method provides more reliable occurrence datasets. Nonetheless, we suggest predictions reflecting the species apparent distribution (i.e. a combination of species distribution and the probability of detecting it). Consequently, we also encourage researchers and marine managers to carefully interpret model predictions.  相似文献   

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There is increasing recognition of intraspecific diversity and population structure within marine fish species, yet there is little direct evidence of the isolating mechanisms that maintain it or documentation of its ecological extent. We analyzed depth and temperature histories collected by electronic data storage tags retrieved from 104 Atlantic cod at liberty ≥1 year to evaluate a possible isolating mechanisms maintaining population structure within the Icelandic cod stock. This stock consists of two distinct behavioral types, resident coastal cod and migratory frontal cod, each occurring within two geographically distinct populations. Despite being captured together on the same spawning grounds, we show the behavioral types seem reproductively isolated by fine-scale differences in spawning habitat selection, primarily depth. Additionally, the different groups occupied distinct seasonal thermal and bathymetric niches that generally demonstrated low levels of overlap throughout the year. Our results indicate that isolating mechanisms, such as differential habitat selection during spawning, might contribute to maintaining diversity and fine-scale population structure in broadcast-spawning marine fishes.  相似文献   

18.
The durations of the phases of the cell cycle were measured at different levels in the jejunal crypts of male Balb/c mice. A mean cell cycle time of 12.3 h was found for the whole crypt. In cell positions 1 and 2, the cell cycle time was 16.7 h, and this time steadily decreased to a value of between 10 and 11 h for cell positions above 11. It is concluded that basally situated crypt cells in the mouse are cycling relatively slowly, and that they form the functional stem cell pool for the crypt. These cells may also compose the potential stem cell pool which repopulates the crypt after death of proliferative cells.  相似文献   

19.
Tandem simple sequence repeats (SSRs) are one of the most popular molecular markers in genetic analysis owing to their ubiquitous occurrence,high reproducibility, multiallelic nature, and codominant mode. High mutability makes SSRs play a role in genome evolution and correspondingly show different patterns. Comparative analysis of genomic SSRs in different taxonomic groups usually focuses on land species, while marine animals have been neglected. This study examined the abundance of genomic SSRs with repeated unit lengths of 1–6 bp in 30 marine animals including nine taxonomic groups and further compared with the land species. More than thousands of SSRs were discovered in every organism which provided a huge resource for the development of molecular markers. Thirty marine animals showed profound differences in SSR characteristics, but some group-specific trends were also found. Both similarities and differences of repeat patterns were discovered between the land and marine species. Two taxon-specific SSR types were discovered: the pentanucleotides motif AGAGG in Euteleostei and the hexanucleotide repeats of ATGTAC in Porifera and Echinodermata. Gene ontology (GO) enrichment analysis of two representative species (Amphimedon queenslandica for Porifera and Strongylocentrotus purpuratus for Echinodermata) revealed functional preference of the ATGTAC motif associated genes, and this might hint at evolutionary significance.  相似文献   

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Examination of 12 healthy volunteers aged 20–56 years was performed to study the EEG changes caused by a tonic squeeze of the distal joint of the little finger of the left and then the right hand. This stimulation caused painful sensations of different intensity (pain on the right was stronger). Spectral power was measured in the ( 1 (8–10.5 Hz) and (2 ranges (10.5–13 Hz) under different conditions. Weak pain led to an increase in the power of the (1 and 2 ranges in the occipital regions. With strong pain, the power of 1 waves increased bilaterally in the posterior regions (O 1, O 2, T 6), as well as in the left frontal region (F 3, F 7). The powers of the 1 and 2 ranges substantially increased relative to the background level after the strong nociceptive stimulation ceased. This finding testified to a latent and inertial character of its effect on the -wave parameters.Translated from Fiziologiya Cheloveka, Vol. 31, No. 2, 2005, pp. 77–84.Original Russian Text Copyright © 2005 by Garkavenko, Gorkovenko, Mankovskaya, Shevko, Lyskov, Kostyukov.  相似文献   

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