259 research outputs found

    ENRICHMENT AND POPULATION OF A GEOSPATIAL ONTOLOGY FOR SEMANTIC INFORMATION EXTRACTION

    Get PDF
    The massive amount of user-generated content available today presents a new challenge for the geospatial domain and a great opportunity to delve into linguistic, semantic, and cognitive aspects of geographic information. Ontology-based information extraction is a new, prominent field in which a domain ontology guides the extraction process and the identification of pre-defined concepts, properties, and instances from natural language texts. The paper describes an approach for enriching and populating a geospatial ontology using both a top-down and a bottom-up approach in order to enable semantic information extraction. The top-down approach is applied in order to incorporate knowledge from existing ontologies. The bottom-up approach is applied in order to enrich and populate the geospatial ontology with semantic information (concepts, relations, and instances) extracted from domain-specific web content

    Gender differences in online collaborative learning groups promoting affective education and social capital

    Get PDF
    This paper reports the results of a study aimed to establish whether the amount and types of conflicts vary in all male, all female and mixed gender groups working in asynchronous collaborative learning online settings. Sixty psychology majors were divided into three groups conducted online by the same teacher. The study show that the levels of participation in the three groups varied in relation to gender composition. Further the results evidenced all female group did have more conflicts then male and mixed groups, but primarily they did not have interpersonal. The female groups´ conflicts seem to be related to goal-oriented process of work

    Superantigenicity of streptococcal M protein.

    Full text link

    Extracting invariant characteristics of sketch maps: Towards place query-by-sketch

    Get PDF
    In geography, invariant aspects of sketches are essential to study because they reflect the human perception of real-world places. A person's perception of a place can be ex-pressed in sketches. In this article, we quantitatively and qualitatively analyzed the characteristics of single objects and characteristics among objects in sketches and the real world to find reliable invariants that can be used to establish references/correspondences between sketch and world in a matching process. These characteristics include category, shape, name, and relative size of each object. Moreover, quantity and spatial relationships—such as topological, or-dering, and location relationships—among all objects are also analyzed to assess consistency between sketched and actual places. The approach presented in this study extracts the reliable invariants for query-by-sketch and prioritizes their relevance for a sketch-map matching process

    Comparative one-month safety and effectiveness of five leading new-generation devices for transcatheter aortic valve implantation

    Get PDF
    Transcatheter aortic valve implantation (TAVI) for aortic stenosis is becoming an appealing alternative to surgical aortic valve replacement in high-risk patients and to medical therapy for inoperable ones. Several new-generation TAVI devices have been recently introduced, but comparative analyses are lacking. We aimed to compare 1-month outcomes associated with such five leading new-generation TAVI devices exploiting data collected in the prospective observational RISPEVA (Registro Italiano GISE sull’impianto di Valvola Aortica Percutanea) Study. We queried the dataset of the ongoing RISPEVA study to retrieve baseline, procedural and 1-month outcome details of patients undergoing TAVI with Acurate, Evolut, Portico, Lotus, and Sapien3. Analysis was based on unadjusted and propensity score-adjusted methods. We included 1976 patients, 234 (11.8%) treated with Acurate, 703 (35.6%) with Evolut, 151 (7.6%) with Lotus, 347 (17.6%) with Portico, and 541 (27.4%) with Sapien3. Unadjusted analysis for baseline features highlighted several significant differences, and other discrepancies were found for procedural features. Despite these differences, device and procedural success were similarly high (ranging from 98.0% to 99.4%, p > 0.05). However, procedural valve migration appeared more common with Acurate (p = 0.007), and major bleeding with Sapien3 (p = 0.002). Unadjusted analysis for 1-month outcomes also highlighted significant differences in the composite of death, stroke, myocardial infarction, major vascular complication, major bleeding, or renal failure (favoring Portico, p < 0.001), major vascular complications (favoring Lotus, p < 0.001), renal failure (favoring Portico, p = 0.035), and permanent pacemaker implantation (favoring Acurate, p < 0.001). Propensity score-adjusted analyses showed lower rates of major adverse events with Evolut and Portico (p < 0.05), major vascular complications with Lotus and Portico (p < 0.05), renal failure with Sapien3 (p < 0.05) and permanent pacemaker implantation with Acurate (p < 0.05). In conclusion, new-generation TAVI devices have different profiles of early comparative safety and efficacy. These findings should be taken into account for individualized decision making and patient management

    A RasGAP SH3 Peptide Aptamer Inhibits RasGAP-Aurora Interaction and Induces Caspase-Independent Tumor Cell Death

    Get PDF
    The Ras GTPase-activating protein RasGAP catalyzes the conversion of active GTP-bound Ras into inactive GDP-bound Ras. However, RasGAP also acts as a positive effector of Ras and exerts an anti-apoptotic activity that is independent of its GAP function and that involves its SH3 (Src homology) domain. We used a combinatorial peptide aptamer approach to select a collection of RasGAP SH3 specific ligands. We mapped the peptide aptamer binding sites by performing yeast two-hybrid mating assays against a panel of RasGAP SH3 mutants. We examined the biological activity of a peptide aptamer targeting a pocket delineated by residues D295/7, L313 and W317. This aptamer shows a caspase-independent cytotoxic activity on tumor cell lines. It disrupts the interaction between RasGAP and Aurora B kinase. This work identifies the above-mentioned pocket as an interesting therapeutic target to pursue and points its cognate peptide aptamer as a promising guide to discover RasGAP small-molecule drug candidates

    Polymorphisms in Toll-like receptor genes influence antibody responses to cytomegalovirus glycoprotein B vaccine

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Congenital Cytomegalovirus (CMV) infection is an important medical problem that has yet no current solution. A clinical trial of CMV glycoprotein B (gB) vaccine in young women showed promising efficacy. Improved understanding of the basis for prevention of CMV infection is essential for developing improved vaccines.</p> <p>Results</p> <p>We genotyped 142 women previously vaccinated with three doses of CMV gB for single nucleotide polymorphisms (SNPs) in TLR 1-4, 6, 7, 9, and 10, and their associated intracellular signaling genes. SNPs in the platelet-derived growth factor receptor (PDGFRA) and integrins were also selected based on their role in binding gB. Specific SNPs in TLR7 and IKBKE (inhibitor of nuclear factor kappa-B kinase subunit epsilon) were associated with antibody responses to gB vaccine. Homozygous carriers of the minor allele at four SNPs in TLR7 showed higher vaccination-induced antibody responses to gB compared to heterozygotes or homozygotes for the common allele. SNP rs1953090 in IKBKE was associated with changes in antibody level from second to third dose of vaccine; homozygotes for the minor allele exhibited lower antibody responses while homozygotes for the major allele showed increased responses over time.</p> <p>Conclusions</p> <p>These data contribute to our understanding of the immunogenetic mechanisms underlying variations in the immune response to CMV vaccine.</p
    • …
    corecore