The Experts below are selected from a list of 21 Experts worldwide ranked by ideXlab platform

T.o. Braham - One of the best experts on this subject based on the ideXlab platform.

  • DEXA Workshop - Integrating of inherit and reference links in the building of an object distributed database management system
    Database and Expert Systems Applications. 8th International Conference DEXA '97. Proceedings, 1997
    Co-Authors: T.o. Braham
    Abstract:

    The building of an object distributed database management system (ODDBMS) integrates the linked concepts of the distributed database management and the linked concepts of objects. Among the object concepts, the author focuses interest on the following two concepts: inherit link and reference link. The author studies how these links, adapted to a distributed system, influence the global request (transaction) decomposition into local sub-requests (sub-transactions). The author also studies how these links have to be taken into account during the different types of management that the distributed system has to use in order to be consistent and reliable. The originality of the proposition is that one integrates the inheritance concept in a distributed system by extending it to an aspect related to duplication. A class which inherits from another class implanted on another site sees its Inherited Attribute occurrences duplicated on its implantation site. The author proposes with an example of ODDB, an implementation of the methods used in description of classes and shows how they can be used in examples of update transactions.

  • Integrating of inherit and reference links in the building of an object distributed database management system
    Database and Expert Systems Applications. 8th International Conference DEXA '97. Proceedings, 1997
    Co-Authors: T.o. Braham
    Abstract:

    The building of an object distributed database management system (ODDBMS) integrates the linked concepts of the distributed database management and the linked concepts of objects. Among the object concepts, the author focuses interest on the following two concepts: inherit link and reference link. The author studies how these links, adapted to a distributed system, influence the global request (transaction) decomposition into local sub-requests (sub-transactions). The author also studies how these links have to be taken into account during the different types of management that the distributed system has to use in order to be consistent and reliable. The originality of the proposition is that one integrates the inheritance concept in a distributed system by extending it to an aspect related to duplication. A class which inherits from another class implanted on another site sees its Inherited Attribute occurrences duplicated on its implantation site. The author proposes with an example of ODDB, an implementation of the methods used in description of classes and shows how they can be used in examples of update transactions.

Li Kuan - One of the best experts on this subject based on the ideXlab platform.

  • THE HERBIVORY EFFECTS OF SNAIL RADIX SWINHOEI ON SUBMERGED PLANT COMMUNITY
    2020
    Co-Authors: Li Kuan
    Abstract:

    The herbivory effects by snail Radix swinhoei on submerged plant community were examined in an experimental station under artificial controlling in Taihu Lake, Jiangsu of China from May to July, 2006. The results showed that the grazing activity of the snail depressed the growth of 4 submerged plant species, and the total biomass of plant community were negatively correlated to snail density significantly. The plant community structure was clearly affected by the snail. With the snail density increasing, the summed dominance ratio decreased for Potamogeton malaianu and Vallisneria spiralis, whereas those of Elodea nuttallii and Hydrilla verticillata steadily increased. The main influential factors on the change of community structure were discussed in this paper. It was thought that the Inherited Attribute of plant decided the dominance of E. nuttallii and H. verticillata in local plant community; and the herbivory preference of the snail on P. malaianu and V. spiralis speeded up the occupancy of dominance by other 2 plants.

Quentin D. Wheeler - One of the best experts on this subject based on the ideXlab platform.

  • AN AMPLIFICATION OF THE PHYLOGENETIC SPECIES CONCEPT
    Cladistics, 1990
    Co-Authors: Kevin C. Nixon, Quentin D. Wheeler
    Abstract:

    Abstract— The goal of a phylogenetic species concept is to reveal the smallest units that are analysable by cladistic methods and interpretable as the result of phylogenctic history. We define species as the smallest aggregation of populations (sexual) or lineagcs (asexual) diagnosable by a unique combination of character states in comparable individuals (semaphoronts). A character state is an Inherited Attribute distributed among all comparable individuals (semaphoronts) of the same historical population, clade, or terminal lineage. This definition of species is character-based and pattern oriented. Evolutionary explanations of phylogenetic species are consistent with contemporary explanations of processes of speciation, but require only the assumption of nested hierarchical pattern. We discuss the compatibility of the phylogenetic species concept with various biological needs for species and justify its use at the exclusion of alternative species concepts.

Kevin C. Nixon - One of the best experts on this subject based on the ideXlab platform.

  • AN AMPLIFICATION OF THE PHYLOGENETIC SPECIES CONCEPT
    Cladistics, 1990
    Co-Authors: Kevin C. Nixon, Quentin D. Wheeler
    Abstract:

    Abstract— The goal of a phylogenetic species concept is to reveal the smallest units that are analysable by cladistic methods and interpretable as the result of phylogenctic history. We define species as the smallest aggregation of populations (sexual) or lineagcs (asexual) diagnosable by a unique combination of character states in comparable individuals (semaphoronts). A character state is an Inherited Attribute distributed among all comparable individuals (semaphoronts) of the same historical population, clade, or terminal lineage. This definition of species is character-based and pattern oriented. Evolutionary explanations of phylogenetic species are consistent with contemporary explanations of processes of speciation, but require only the assumption of nested hierarchical pattern. We discuss the compatibility of the phylogenetic species concept with various biological needs for species and justify its use at the exclusion of alternative species concepts.

Robin C. Allshire - One of the best experts on this subject based on the ideXlab platform.

  • RNAi-Mediated Chromatin Silencing in Fission Yeast
    Current Topics in Microbiology and Immunology, 2020
    Co-Authors: Sharon A. White, Robin C. Allshire
    Abstract:

    In the fission yeast Schizosaccharomyces pombe, the RNAi pathway plays an important role in the formation and maintenance of heterochromatin. Heterochromatin, or silent chromatin, is an epigenetically Inherited Attribute of eukaryotic chromosomes which is required for gene regulation, chromosome segregation and maintenance of genome stability. In S. pombe, heterochromatin forms on related repetitive DNA sequences at specific loci. These repetitive sequences, in concert with the RNAi machinery, are thought to attract several proteins including chromatin-modifying enzymes which act to promote heterochromatin formation. The purification of complexes participating in heterochromatin formation has allowed us to begin to analyse in detail the processes involved. In the future this will help us to understand how the RNAi machinery acts to induce the chromatin modifications which lead to heterochromatin assembly in fission yeast.