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Based on the detailed morphological study of the type species of the genus Multisphaera Nazarov and Afanasieva, the author emends the status and diagnosis of this genus and of the subfamily Multisphaerinae Nazarov and Afanasieva. He found that the initial spicule of the type species is not multi-rayed, as initially thought, but a tetrahedral spicule. Accordingly, the genus is assigned to the former tribe Tetrentactiniini Kozur and Mostler that is herein raised to the family rank and comprises all Upper Devonian to lower Permian genera with a tetrahedral initial spicule. Consequently, the subfamily Multisphaerinae is considered a junior synonym of the family Tetrentactiniidae. To better solve the taxonomic problems of this family the author compares the morphological diversity of its members with the morphological diversity of the lower Tithonian (uppermost Jurassic) tetrahedral spicule-bearing entactinarian Radiolaria occurring in the Solnhofen area, southern Germany. Although these genera have the same type of spicule as the Paleozoic ones, they seem to belong to a new family because between the lower Tithonian and the lower Permian genera there is a long time interval of about 120 Ma in which no radiolarians with a tetrahedral initial spicule have been recorded so far. This comparison shows once more the conservative character of the initial spicule and the wide morphological diversity of the extraspicular shell.  相似文献   

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《Anthrozo?s》2013,26(4):252-256
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《Genetica》2000,109(3):283-285
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MITOP (http://www.mips.biochem.mpg.de/proj/medgen/mitop/) is a comprehensive database for genetic and functional information on both nuclear- and mitochondrial-encoded proteins and their genes. The five species files--Saccharomyces cerevisiae, Mus musculus, Caenorhabditis elegans, Neurospora crassa and Homo sapiens--include annotated data derived from a variety of online resources and the literature. A wide spectrum of search facilities is given in the overlapping sections 'Gene catalogues', 'Protein catalogues', 'Homologies', 'Pathways and metabolism' and 'Human disease catalogue' including extensive references and hyperlinks to other databases. Central features are the results of various homology searches, which should facilitate the investigations into interspecies relationships. Precomputed FASTA searches using all the MITOP yeast protein entries and a list of the best human EST hits with graphical cluster alignments related to the yeast reference sequence are presented. The orthologue tables with cross-listings to all the protein entries for each species in MITOP have been expanded by adding the genomes of Rickettsia prowazeckii and Escherichia coli. To find new mitochondrial proteins the complete yeast genome has been analyzed using the MITOPROT program which identifies mitochondrial targeting sequences. The 'Human disease catalogue' contains tables with a total of 110 human diseases related to mitochondrial protein abnormalities, sorted by clinical criteria and age of onset. MITOP should contribute to the systematic genetic characterization of the mitochondrial proteome in relation to human disease.  相似文献   

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Anthropogenic transformation of the biomes, 1700 to 2000   总被引:5,自引:0,他引:5  
Aim To map and characterize anthropogenic transformation of the terrestrial biosphere before and during the Industrial Revolution, from 1700 to 2000. Location Global. Methods Anthropogenic biomes (anthromes) were mapped for 1700, 1800, 1900 and 2000 using a rule‐based anthrome classification model applied to gridded global data for human population density and land use. Anthropogenic transformation of terrestrial biomes was then characterized by map comparisons at century intervals. Results In 1700, nearly half of the terrestrial biosphere was wild, without human settlements or substantial land use. Most of the remainder was in a seminatural state (45%) having only minor use for agriculture and settlements. By 2000, the opposite was true, with the majority of the biosphere in agricultural and settled anthromes, less than 20% seminatural and only a quarter left wild. Anthropogenic transformation of the biosphere during the Industrial Revolution resulted about equally from land‐use expansion into wildlands and intensification of land use within seminatural anthromes. Transformation pathways differed strongly between biomes and regions, with some remaining mostly wild but with the majority almost completely transformed into rangelands, croplands and villages. In the process of transforming almost 39% of earth's total ice‐free surface into agricultural land and settlements, an additional 37% of global land without such use has become embedded within agricultural and settled anthromes. Main conclusions Between 1700 and 2000, the terrestrial biosphere made the critical transition from mostly wild to mostly anthropogenic, passing the 50% mark early in the 20th century. At present, and ever more in the future, the form and process of terrestrial ecosystems in most biomes will be predominantly anthropogenic, the product of land use and other direct human interactions with ecosystems. Ecological research and conservation efforts in all but a few biomes would benefit from a primary focus on the novel remnant, recovering and managed ecosystems embedded within used lands.  相似文献   

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中国科学院院士、我们敬爱的老师卢衍豪教授 (1913- 2 0 0 0 )逝世已一年多了 ,但是他对科学事业的执着追求和奉献精神一直留在我们心中。我们深切缅怀他对我国地层古生物事业所作的杰出贡献。卢衍豪院士是国内外著名的古生物学家和地层学家 ,在我国和国际地学界享有崇高的声誉。卢衍豪教授 1913年出生于福建省永定县 ,1937年毕业于北京大学地质系 ,获理学学士学位。毕业后留校任助教 ,在葛利普和孙云铸教授的影响下 ,他从事三叶虫研究。在西南联大 (1938- 194 1)期间 ,他开始对我国西南地区早寒武世三叶虫研究 ,首次建立了我国下寒武统地层…  相似文献   

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