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End date: 2021 × Start date: 2021 × Type: Article × Version: submittedVersion ×

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    Open Access im Blick! Mehr Sichtbarkeit von Open-Access-Publikationen in der Bibliothek – Projekt visOA
    (Berlin : De Gruyter, 2020) Geith, Uwe; Kraß, Thomas
    In order to bring Open Access publications more into the perception of library users, it is necessary to make them more visible. In the visOA project, carried out by the NTNM library of the INM, Open Access publications were clearly highlighted in the OPAC as well as in the Discovery System and in the publication lists of the INM. A self-programmed virtual journal display (VIDIJO) also offers a subject-specific selection of Open Access journals. The effectiveness of the measures taken in the project was verified by accompanying research.
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    Compact representations for efficient storage of semantic sensor data
    (Dordrecht : Springer Science + Business Media B.V, 2021) Karim, Farah; Vidal, Maria-Esther; Auer, Sören
    Nowadays, there is a rapid increase in the number of sensor data generated by a wide variety of sensors and devices. Data semantics facilitate information exchange, adaptability, and interoperability among several sensors and devices. Sensor data and their meaning can be described using ontologies, e.g., the Semantic Sensor Network (SSN) Ontology. Notwithstanding, semantically enriched, the size of semantic sensor data is substantially larger than raw sensor data. Moreover, some measurement values can be observed by sensors several times, and a huge number of repeated facts about sensor data can be produced. We propose a compact or factorized representation of semantic sensor data, where repeated measurement values are described only once. Furthermore, these compact representations are able to enhance the storage and processing of semantic sensor data. To scale up to large datasets, factorization based, tabular representations are exploited to store and manage factorized semantic sensor data using Big Data technologies. We empirically study the effectiveness of a semantic sensor’s proposed compact representations and their impact on query processing. Additionally, we evaluate the effects of storing the proposed representations on diverse RDF implementations. Results suggest that the proposed compact representations empower the storage and query processing of sensor data over diverse RDF implementations, and up to two orders of magnitude can reduce query execution time.
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    Das #vBIB20-Experiment: spontan, agil und virtuell
    (Heidelberg : Universitätsbibliothek, 2020) Bielesch, Stefan; Engelkenmeier, Ute; Kösters, Jens; Petri, Nicole; Stöhr, Matti; Stummeyer, Sabine
    After the cancellation of the 109th German Librarians' Day in Hannover, the #vBIB20 took place from 26-28 May 2020 as an alternative planned at short notice, which was conducted as a web conference. The article briefly examines from the point of view of the organisation (TIB Hannover, Association of Information and Library Professionals BIB) the challenges and experiences in the implementation of the pure online conference, which was unprecedented in the German-speaking library community on this scale.
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    Possibilities and Limitations of Photoactivatable Cytochalasin D for the Spatiotemporal Regulation of Actin Dynamics
    (Washington, D.C. : American Chemical Society, 2020) Nair, Roshna V.; Zhao, Shifang; Terriac, Emmanuel; Lautenschläger, Franziska; Hetmanski, Joseph H.R.; Caswell, Patrick T.; del Campo, Aranzazu
    The study of the actin cytoskeleton and related cellular processes requires tools to specifically interfere with actin dynamics in living cell cultures, ideally with spatiotemporal control and compatible with real time imaging. A phototriggerable derivative of the actin disruptor Cytochalasin D (CytoD) is described and tested here. It includes a nitroveratryloxycarbonyl (Nvoc) photoremovable protecting group (PPG) at the hydroxyl group at C7 of CytoD. The attachment of the PPG renders Nvoc-CytoD temporarily inactive, and enables light-dosed delivery of the active drug CytoD to living cells. This article presents the full structural and physicochemical characterization, the toxicity analysis. It is complemented with biological tests to show the time scales (seconds) and spatial resolution (cellular level) achievable with a UV source in a regular microscopy setup
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    Enhancing Virtual Ontology Based Access over Tabular Data with Morph-CSV
    (Amsterdam : IOS Press, 2020) Chaves-Fraga, David; Ruckhaus, Edna; Priyatna, Freddy; Vidal, Maria-Esther; Corchio, Oscar
    Ontology-Based Data Access (OBDA) has traditionally focused on providing a unified view of heterogeneous datasets, either by materializing integrated data into RDF or by performing on-the fly querying via SPARQL query translation. In the specific case of tabular datasets represented as several CSV or Excel files, query translation approaches have been applied by considering each source as a single table that can be loaded into a relational database management system (RDBMS). Nevertheless, constraints over these tables are not represented; thus, neither consistency among attributes nor indexes over tables are enforced. As a consequence, efficiency of the SPARQL-to-SQL translation process may be affected, as well as the completeness of the answers produced during the evaluation of the generated SQL query. Our work is focused on applying implicit constraints on the OBDA query translation process over tabular data. We propose Morph-CSV, a framework for querying tabular data that exploits information from typical OBDA inputs (e.g., mappings, queries) to enforce constraints that can be used together with any SPARQL-to-SQL OBDA engine. Morph-CSV relies on both a constraint component and a set of constraint operators. For a given set of constraints, the operators are applied to each type of constraint with the aim of enhancing query completeness and performance. We evaluate Morph-CSV in several domains: e-commerce with the BSBM benchmark; transportation with a benchmark using the GTFS dataset from the Madrid subway; and biology with a use case extracted from the Bio2RDF project. We compare and report the performance of two SPARQL-to-SQL OBDA engines, without and with the incorporation of MorphCSV. The observed results suggest that Morph-CSV is able to speed up the total query execution time by up to two orders of magnitude, while it is able to produce all the query answers.