35 research outputs found
Linking early-life NMDAR hypofunction and oxidative stress in schizophrenia pathogenesis.
Molecular, genetic and pathological evidence suggests that deficits in GABAergic parvalbumin-positive interneurons contribute to schizophrenia pathophysiology through alterations in the brain's excitation-inhibition balance that result in impaired behaviour and cognition. Although the factors that trigger these deficits are diverse, there is increasing evidence that they converge on a common pathological hub that involves NMDA receptor hypofunction and oxidative stress. These factors have been separately linked to schizophrenia pathogenesis, but evidence now suggests that they are mechanistically interdependent and contribute to a common schizophrenia-associated pathology
Identifying Consistent Statements about Numerical Data with Dispersion-Corrected Subgroup Discovery
Existing algorithms for subgroup discovery with numerical targets do not
optimize the error or target variable dispersion of the groups they find. This
often leads to unreliable or inconsistent statements about the data, rendering
practical applications, especially in scientific domains, futile. Therefore, we
here extend the optimistic estimator framework for optimal subgroup discovery
to a new class of objective functions: we show how tight estimators can be
computed efficiently for all functions that are determined by subgroup size
(non-decreasing dependence), the subgroup median value, and a dispersion
measure around the median (non-increasing dependence). In the important special
case when dispersion is measured using the average absolute deviation from the
median, this novel approach yields a linear time algorithm. Empirical
evaluation on a wide range of datasets shows that, when used within
branch-and-bound search, this approach is highly efficient and indeed discovers
subgroups with much smaller errors.Comment: significance of empirical results tested; additional illustrations;
table of used notation
Analysis of parapoxvirus genomes.
Eight stomatitis papulosa (SP), four orf and two milker's nodes (MN) virus isolates were compared by restriction enzyme analysis. Considerable genetic heterogeneity was found not only between isolates belonging to the three different taxonomic groups but also between members of the same group. This heterogeneity precludes classification of parapoxviruses simply by comparison of their DNA cleavage patterns. Restriction maps were therefore prepared for 12 parapoxvirus DNAs. Fragments from defined regions of the genome were then selected and used as probes for cross-hybridizations to all other parapoxvirus DNAs. DNA fragments derived from an internal region of the genome hybridized strongly to all parapoxvirus isolates examined. In contrast, cross-hybridization of the end region of the DNA molecule was observed only between members of the same virus group. Molecular hybridization as a means of classifying parapoxvirus isolates is discussed