Knowledge Questions from Knowledge Graphs

We address the novel problem of automatically generating quiz-style knowledge questions from a knowledge graph such as DBpedia. Questions of this kind have ample applications, for instance, to educate users about or to evaluate their knowledge in a specific domain. To solve the problem, we propose an end-to-end approach. The approach first selects a named entity from the knowledge graph as an answer. It then generates a structured triple-pattern query, which yields the answer as its sole result. If a multiple-choice question is desired, the approach selects alternative answer options. Finally, our approach uses a template-based method to verbalize the structured query and yield a natural language question. A key challenge is estimating how difficult the generated question is to human users. To do this, we make use of historical data from the Jeopardy! quiz show and a semantically annotated Web-scale document collection, engineer suitable features, and train a logistic regression classifier to predict question difficulty. Experiments demonstrate the viability of our overall approach

Measuring Conceptual Similarity in Ontologies: How Bad is a Cheap Measure?

Abstract. Several attempts have been made to develop similarity mea-sures for ontologies. Motivated by finding problems in existing measures, we design a new family of measures to address these problems. We carry out an empirical study to explore how good the new measures are and to investigate how likely it is to encounter specific task-oriented problems when using a bad similarity measure.

Localized TWIST1 and TWIST2 basic domain substitutions cause four distinct human diseases that can be modeled in C. elegans

Twist transcription factors, members of the basic helix-loop-helix family, play crucial roles in mesoderm development in all animals. Humans have two paralogous genes, TWIST1 and TWIST2, and mutations in each gene have been identified in specific craniofacial disorders. Here we describe a new clinical entity, Sweeney-Cox syndrome, associated with distinct de novo amino acid substitutions (p.Glu117Val and p.Glu117Gly) at a highly conserved glutamic acid residue located in the basic DNA binding domain of TWIST1, in two subjects with frontonasal dysplasia and additional malformations. Although about one hundred different TWIST1 mutations have been reported in patients with the dominant haploinsufficiency Saethre-Chotzen syndrome (typically associated with craniosynostosis), substitutions uniquely affecting the Glu117 codon were not observed previously. Recently, subjects with Barber-Say and Ablepharon-macrostomia syndromes were found to harbor heterozygous missense substitutions in the paralogous glutamic acid residue in TWIST2 (p.Glu75Ala, p.Glu75Gln, and p.Glu75Lys). To study systematically the effects of these substitutions in individual cells of the developing mesoderm, we engineered all five disease-associated alleles into the equivalent Glu29 residue encoded by hlh-8, the single Twist homolog present in C. elegans. This allelic series revealed that different substitutions exhibit graded severity, in terms of both gene expression and cellular phenotype, which we incorporate into a model explaining the various human disease phenotypes. The genetic analysis favors a predominantly dominant-negative mechanism for the action of amino acid substitutions at this highly conserved glutamate residue and illustrates the value of systematic mutagenesis of C. elegans for focused investigation of human disease processes

Localized TWIST1 and TWIST2 basic domain substitutions cause four distinct human diseases that can be modeled in C. elegans

Twist transcription factors, members of the basic helix-loop-helix family, play crucial roles in mesoderm development in all animals. Humans have two paralogous genes, TWIST1 and TWIST2, and mutations in each gene have been identified in specific craniofacial disorders. Here we describe a new clinical entity, Sweeney-Cox syndrome, associated with distinct de novo amino acid substitutions (p.Glu117Val and p.Glu117Gly) at a highly conserved glutamic acid residue located in the basic DNA binding domain of TWIST1, in two subjects with frontonasal dysplasia and additional malformations. Although about one hundred different TWIST1 mutations have been reported in patients with the dominant haploinsufficiency Saethre-Chotzen syndrome (typically associated with craniosynostosis), substitutions uniquely affecting the Glu117 codon were not observed previously. Recently, subjects with Barber-Say and Ablepharon-macrostomia syndromes were found to harbor heterozygous missense substitutions in the paralogous glutamic acid residue in TWIST2 (p.Glu75Ala, p.Glu75Gln, and p.Glu75Lys). To study systematically the effects of these substitutions in individual cells of the developing mesoderm, we engineered all five disease-associated alleles into the equivalent Glu29 residue encoded by hlh-8, the single Twist homolog present in C. elegans. This allelic series revealed that different substitutions exhibit graded severity, in terms of both gene expression and cellular phenotype, which we incorporate into a model explaining the various human disease phenotypes. The genetic analysis favors a predominantly dominant-negative mechanism for the action of amino acid substitutions at this highly conserved glutamate residue and illustrates the value of systematic mutagenesis of C. elegans for focused investigation of human disease processes

Computing Minimal Projection Modules for ELHr -Terminologies

International audienceFor the development of large-scale representations of knowledge , the application of methodologies and design principles becomes relevant. The knowledge may be organized in ontologies in a modular and hierarchical fashion. An upper-level (reference) ontology typically provides specifications of requirements, functions, design or standards that are to be complied with by domain ontologies for a specific task on a lower level (task ontology) in the hierarchy. Verifying whether and how specifications have been implemented by a task ontology becomes a challenge when relevant axioms of the domain ontology need to be inspected. We consider specifications to be defined using entailments of certain queries over a given vocabulary. For selecting the relevant axioms from task ontologies, we propose a novel module notion called projection module that entails the queries that follow from a reference ontology. We develop algorithms for computing minimal projection modules of Description Logic terminologies for subsumption, instance and conjunctive queries