7,329 research outputs found
Wodzicki residue and anomalies of current algebras
The commutator anomalies (Schwinger terms) of current algebras in
dimensions are computed in terms of the Wodzicki residue of pseudodifferential
operators; the result can be written as a (twisted) Radul 2-cocycle for the Lie
algebra of PSDO's. The construction of the (second quantized) current algebra
is closely related to a geometric renormalization of the interaction
Hamiltonian in gauge theory.Comment: 15 pages, updated version of a talk at the Baltic School in Field
Theory, September 199
Spin-dependent structure functions and for inclusive spin-half baryon production in electron-positron annihilation
Two spin-dependent structure functions and for the
inclusive spin-half baryon production in electron-positron annihilation are
studied in the context of QCD factorization as well as in the naive quark
parton model. As a result, it is found that the sum of and is related to and , two quark fragmentation functions
defined by Jaffe and Ji. In connection with the measurement of quark
fragmentation functions, the possible phenomenological consequences are
discussed.Comment: RevTex, four Ps figures, to appear in Phys. Rev.
Phenex: Ontological Annotation of Phenotypic Diversity
Phenex is a platform-independent desktop application designed to facilitate efficient and consistent annotation of phenotypic variation using Entity-Quality syntax, drawing on terms from community ontologies for anatomical entities, phenotypic qualities, and taxonomic names. Despite the centrality of the phenotype to so much of biology, traditions for communicating information about phenotypes are idiosyncratic to different disciplines. Phenotypes seem to elude standardized descriptions due to the variety of traits that compose them and the difficulty of capturing the complex forms and subtle differences among organisms that we can readily observe. Consequently, phenotypes are refractory to attempts at data integration that would allow computational analyses across studies and study systems. Phenex addresses this problem by allowing scientists to employ standard ontologies and syntax to link computable phenotype annotations to evolutionary character matrices, as well as to link taxa and specimens to ontological identifiers. Ontologies have become a foundational technology for establishing shared semantics, and, more generally, for capturing and computing with biological knowledge
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