Extending DBMSs with satellite databases

In this paper, we propose an extensible architecture for database engines where satellite databases are used to scale out and implement additional functionality for a centralized database engine. The architecture uses a middleware layer that offers consistent views and a single system image over a cluster of machines with database engines. One of these engines acts as a master copy while the others are read-only snapshots which we call satellites. The satellites are lightweight DBMSs used for scalability and to provide functionality difficult or expensive to implement in the main engine. Our approach also supports the dynamic creation of satellites to be able to autonomously adapt to varying loads. The paper presents the architecture, discusses the research problems it raises, and validates its feasibility with extensive experimental result

New and emerging perspectives for technology assessment: Malevolent creativity and civil security

The characteristics of new technologies can cause significant harm to society. This does not only apply to unintended consequences, but even more so when the technologies are used for malicious purposes. The latter can be observed in the domain of civil security. Here, negative developments such as social polarization, increasing radicalization, and democratic regression alongside a deteriorating security situation are increasingly associated with technological innovation and malevolent creativity. As society becomes more and more aware of such correlations, technology assessment is called upon to provide orientation knowledge. This requires appropriate approaches and knowledge tools to assess the potential role of technology in relation to radicalization and political extremism.Die Eigenschaften neuer Technologien können der Gesellschaft erheblichen Schaden zufügen. Dies gilt nicht nur für unbeabsichtigte Folgen, sondern vor allem dann, wenn die Technologien für böswillige Zwecke eingesetzt werden. Letzteres ist im Bereich der zivilen Sicherheit zu beobachten. Hier werden negative Entwicklungen wie soziale Polarisierung, zunehmende Radikalisierung und demokratischer Rückschritt sowie eine sich verschlechternde Sicherheitslage zunehmend mit technologischer Innovation und malevolenter Kreativität in Verbindung gebracht. Da sich die Gesellschaft solcher Zusammenhänge mehr und mehr bewusst wird, ist die Technikfolgenabschätzung gefordert, Orientierungswissen bereitzustellen. Dazu bedarf es geeigneter Ansätze und Wissensinstrumente, um die potenzielle Rolle der Technik in Bezug auf Radikalisierung und politischem Extremismus zu bewerten

NCAM 180 Acting via a Conserved C-Terminal Domain and MLCK Is Essential for Effective Transmission with Repetitive Stimulation

SummaryNCAM 180 isoform null neuromuscular junctions are unable to effectively mobilize and exocytose synaptic vesicles and thus exhibit periods of total transmission failure during high-frequency repetitive stimulation. We have identified a highly conserved C-terminal (KENESKA) domain on NCAM that is required to maintain effective transmission and demonstrate that it acts via a pathway involving MLCK and probably myosin light chain (MLC) and myosin II. By perfecting a method of introducing peptides into adult NMJs, we tested the hypothesized role of proteins in this pathway by competitive disruption of protein-protein interactions. The effects of KENESKA and other peptides on MLCK and MLC activation and on failures in both wild-type and NCAM 180 null junctions supported this pathway, and serine phosphorylation of KENESKA was critical. We propose that this pathway is required to replenish synaptic vesicles utilized during high levels of exocytosis by facilitating myosin-driven delivery of synaptic vesicles to active zones or their subsequent exocytosis

Microdomain Ca2+ Activation during Exocytosis in Paramecium Cells. Superposition of Local Subplasmalemmal Calcium Store Activation by Local Ca2+ Influx

In Paramecium tetraurelia, polyamine-triggered exocytosis is accompanied by the activation of Ca2+-activated currents across the cell membrane (Erxleben, C., and H. Plattner. 1994. J. Cell Biol. 127:935– 945). We now show by voltage clamp and extracellular recordings that the product of current × time (As) closely parallels the number of exocytotic events. We suggest that Ca2+ mobilization from subplasmalemmal storage compartments, covering almost the entire cell surface, is a key event. In fact, after local stimulation, Ca2+ imaging with high time resolution reveals rapid, transient, local signals even when extracellular Ca2+ is quenched to or below resting intracellular Ca2+ concentration ([Ca2+]e ⩽ [Ca2+]i). Under these conditions, quenched-flow/freeze-fracture analysis shows that membrane fusion is only partially inhibited. Increasing [Ca2+]e alone, i.e., without secretagogue, causes rapid, strong cortical increase of [Ca2+]i but no exocytosis. In various cells, the ratio of maximal vs. minimal currents registered during maximal stimulation or single exocytotic events, respectively, correlate nicely with the number of Ca stores available. Since no quantal current steps could be observed, this is again compatible with the combined occurrence of Ca2+ mobilization from stores (providing close to threshold Ca2+ levels) and Ca2+ influx from the medium (which per se does not cause exocytosis). This implies that only the combination of Ca2+ flushes, primarily from internal and secondarily from external sources, can produce a signal triggering rapid, local exocytotic responses, as requested for Paramecium defense

How to Juggle Columns: An Entropy-Based Approach for Table Compression

Many relational databases exhibit complex dependencies between data attributes, caused either by the nature of the underlying data or by explicitly denormalized schemas. In data warehouse scenarios, calculated key figures may be materialized or hierarchy levels may be held within a single dimension table. Such column correlations and the resulting data redundancy may result in additional storage requirements. They may also result in bad query performance if inappropriate independence assumptions are made during query compilation. In this paper, we tackle the specific problem of detecting functional dependencies between columns to improve the compression rate for column-based database systems, which both reduces main memory consumption and improves query performance. Although a huge variety of algorithms have been proposed for detecting column dependencies in databases, we maintain that increased data volumes and recent developments in hardware architectures demand novel algorithms with much lower runtime overhead and smaller memory footprint. Our novel approach is based on entropy estimations and exploits a combination of sampling and multiple heuristics to render it applicable for a wide range of use cases. We demonstrate the quality of our approach by means of an implementation within the SAP NetWeaver Business Warehouse Accelerator. Our experiments indicate that our approach scales well with the number of columns and produces reliable dependence structure information. This both reduces memory consumption and improves performance for nontrivial queries

Malevolent creativity and civil security: The ambivalence of emergent technologies

The characteristics of new technologies can cause significant harm to society. This does not only apply to unintended consequences, but even more so when the technologies are used for malicious purposes. The latter can be observed in the domain of civil security. Here, negative developments such as social polarization, increasing radicalization, and democratic regression alongside a deteriorating security situation are increasingly associated with technological innovation and malevolent creativity. As society becomes more and more aware of such correlations, technology assessment is called upon to provide orientation knowledge. This requires appropriate approaches and knowledge tools to assess the potential role of technology in relation to radicalization and political extremism

Aktuelle Befunde aus dem Technologiemonitoring: Extremismus und Radikalisierung im Metaverse

Das vom Institut für Technikfolgenabschätzung und Systemanalyse (ITAS) am Karlsruher Institut für Technologie (KIT) verantwortete Technologiemonitoring untersucht Entwicklungspotenziale und -trends neuer Technologien, die das Potenzial haben, die Möglichkeiten extremistischer Akteur*innen zu erweitern. Eine aktuell viel diskutierte neue Technologie, welcher weitreichende Implikationen für Phänomene von Extremismus und Radikalisierung zugeschrieben werden, ist das Metaverse. Dabei handelt es sich um die Vision eines durch Virtual Reality (VR)erweiterten Internets, das sich als plattformübergreifende digitale Umwelt auf nahezu sämtliche Lebensbereiche erstrecken und dabei den Nutzer*innen immersive soziale Interaktion in Echtzeit ermöglichen soll. Bislang handelt es sich beim Metaverse nur um eine Vision, deren Verwirklichung noch weit in der Zukunft liegt, die aber zugleich den Beginn einer technologischen Entwicklung markiert und dabei Ansprüche an Funktionalität, soziale Wirkung und technologischen Prozess formuliert. Mit Hilfe der in der Technikfolgenabschätzung entwickelten Methode des Vision Assessments zeigen wir alternative Entwicklungsmöglichkeiten für ein zukünftiges Metaverse auf, um dabei auch gesellschaftliche Folgen in Bezug auf Extremismus und Radikalisierung sichtbar, diskutierbar und damit gestaltbar zu machen. Zu diesem Zweck haben wir einen Expert*innen-Workshop mit Teilnehmer*innen aus den Bereichen Extremismusforschung, Kriminologie und Technologie durchgeführt. Dort haben die Expert*innen vier Szenarien entwickelt, die Alternativen aufzeigen, wie sich extremistisches Handeln und Radikalisierung in einem Metaverse im Jahr 2040 möglicherweise verändern und - je nachdem wie dieses gestaltet sein wird - kontrolliert und abgesichert werden könnten. Als zentrale Faktoren für die Handlungsmöglichkeiten extremistischer Akteur*innen in einem Metaverse werden staatliche Regulierung, Moderation von Inhalten, Datenschutz, Jugendschutz sowie technologische Standards ausgemacht. Die Szenarien machen deutlich, dass insbesondere die Rolle des Staates und die Moderation von Inhalten wichtige Faktoren für die Einhegung extremistischer Bestrebungen im Metaverse sind. Damit sind Fragen einer angemessenen Plattform-Governance angesprochen. Hier weisen die Expert*innen auf den Bereich Gaming hin, weil es dort bereits Erfahrungen mit der Verbreitung von Extremismus in immersiven Online-Welten gibt. Weiterhin wird die die Notwendigkeit einer frühzeitigen und umfangreichen Einbindung der zukünftigen Nutzer*innen und zivilgesellschaftlicher Akteur*innen in die Entwicklung hervorgehoben, um eine demokratische Ausgestaltung des Metaverses zu unterstützen. Neben einer solchen Stärkung demokratischer Akteur*innen sollte eine gelingende Governance letztlich eine Multi-Stakeholder-Perspektive im Sinne der Beteiligung politischer Entscheidungsträger*innen, Plattformbetreibenden, Sicherheitsbehörden, Zivilgesellschaft und Forschung berücksichtigen

The metrology system of the VLTI instrument GRAVITY

The VLTI instrument GRAVITY combines the beams from four telescopes and provides phase-referenced imaging as well as precision-astrometry of order 10 microarcseconds by observing two celestial objects in dual-field mode. Their angular separation can be determined from their differential OPD (dOPD) when the internal dOPDs in the interferometer are known. Here, we present the general overview of the novel metrology system which performs these measurements. The metrology consists of a three-beam laser system and a homodyne detection scheme for three-beam interference using phase-shifting interferometry in combination with lock-in amplifiers. Via this approach the metrology system measures dOPDs on a nanometer-level.Comment: 9 pages, 5 figure

Clinical forensic radiology in strangulation victims: forensic expertise based on magnetic resonance imaging (MRI) findings

Based on only one objective and several subjective signs, the forensic classification of strangulation incidents concerning their life-threatening quality can be problematic. Reflecting that it is almost impossible to detect internal injuries of the neck with the standard forensic external examination, we examined 14 persons who have survived manual and ligature strangulation or forearm choke holds using MRI technique (1.5-T scanner). Two clinical radiologists evaluated the neck findings independently. The danger to life was evaluated based on the "classical” external findings alone and in addition to the radiological data. We observed hemorrhaging in the subcutaneous fatty tissue of the neck in ten cases. Other frequent findings were hemorrhages of the neck and larynx muscles, the lymph nodes, the pharynx, and larynx soft tissues. Based on the classical forensic strangulation findings with MRI, eight of the cases were declared as life-endangering incidents, four of them without the presence of petechial hemorrhage but with further signs of impaired brain function due to hypoxia. The accuracy of future forensic classification of the danger to life will probably be increased when it is based not only on one objective and several subjective signs but also on the evidence of inner neck injuries. However, further prospective studies including larger cohorts are necessary to clarify the value of the inner neck injuries in the forensic classification of surviving strangulation victim

Building Tomograph – From Remote Sensing Data of Existing Buildings to Building Energy Simulation Input

Existing buildings often have low energy efficiency standards. For the preparation of retrofits, reliable high-quality data about the status quo is required. However, state-of-the-art analysis methods mainly rely on on-site inspections by experts and hence tend to be cost-intensive. In addition, some of the necessary devices need to be installed inside the buildings. As a consequence, owners hesitate to obtain sufficient information about potential refurbishment measures for their houses and underestimate possible savings. Remote sensing measurement technologies have the potential to provide an easy-to-use and automatable way to energetically analyze existing buildings objectively. To prepare an energetic simulation of the status quo and of possible retrofit scenarios, remote sensing data from different data sources have to be merged and combined with additional knowledge about the building. This contribution presents the current state of a project on the development of new and the optimization of conventional data acquisition methods for the energetic analysis of existing buildings solely based on contactless measurements, general information about the building, and data that residents can obtain with little effort. For the example of a single-family house in Morschenich, Germany, geometrical, semantical, and physical information are derived from photogrammetry and quantitative infrared measurements. Both are performed with the help of unmanned aerial vehicles (UAVs) and are compared to conventional methods for energy efficiency analysis regarding accuracy of and necessary effort for input data for building energy simulation. The concept of an object-oriented building model for measurement data processing is presented. Furthermore, an outlook is given on the project involving advanced remote sensing techniques such as ultrasound and microwave radar application for the measurement of additional energetic building parameters