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Trondal, Jarle, Robyn Keast, David Noble und Rómulo Pinheiro (Hrsg.) (2022) : Governing Complexity in Times of Turbulence : Cheltenham/Northampton: Edward Elgar Publishing. 296 Seiten. £ 105.00
No full textDie Herausforderungen, mit denen Regierungen und Verwaltungen im 21. Jahrhundert konfrontiert sind, lassen sich als multiple Krisen beschreiben. Sie resultieren aber auch aus einer zunehmenden und dauerhaften Komplexität der Gesellschaft und Turbulenzen in deren Entwicklung. Christopher Ansell definierte in einem 2016 erschienenen Buchbeitrag Turbulenz als „situations where demands interact in a highly variable, inconsistent, unexpected, and/or unpredictable manner“. Turbulenz, so seine Schlussfolgerung, erfordere eine anpassungsfähige Politik in flexiblen, d. h. multiplexen, redundanten und lose gekoppelten Organisationen und Institutionen. Der hier vorzustellende Band greift diese theoretischen Überlegungen auf mit dem Ziel, sie in exemplarische Fallstudien zu konkretisieren
Stahlhut, Björn/Lammert, Martin (Hrsg.): Gesamtstaatliche Sicherheitsvorsorge – gerüstet für den Ernstfall!?, 200 S., BWV, Berlin 2022.
No full textDas Sicherheitsumfeld Deutschlands und Europas ist im dynamischen Wandel begriffen. Als Antwort auf die daraus erwachsenen Herausforderungen wurde in den vergangenen Jahren wiederholt eingefordert, staatliche Ansätze müssten „interministeriell“, „ressortübergreifend“, „vernetzt“, „gesamtstaatlich“, oder gar „resilient“ sein. Der Sammelband „Gesamtstaatliche Sicherheitsvorsorge – gerüstet für den Ernstfall!?“ reiht sich somit in eine langwierige Debatte ein. Im Titel stellt er immerhin die zentrale Frage: Ist die Sicherheitsarchitektur Deutschlands in der Praxis fähig, den vielfältigen Bedrohungen der Gegenwart und Zukunft zu begegnen
Investigation of permanent magnet synchronous machines with buried magnets and carbon fiber sleeve for automotive application
Full text linkDue to the limited space available in vehicles, traction drives with high torque densities are a key objective of machine design in the automotive sector. In order to be able to dispense with a multispeed transmission and still achieve high vehicle end speeds, there is also the design objective of a high motor speed. Therefore, permanent magnet synchronous machines with buried magnets are preferred. In the following, a rotor concept is presented as a combination of buried rotor magnets and a carbon fiber sleeve in order to eliminate the radial and tangential rotor iron ribs. The resulting reduction in magnetic flux leakage, in combination with high mechanical strength, leads to an increased magnet utilization for the air-gap field and, thus, allows for a high torque density as well as high maximum speed. A disadvantage, however, is the increased manufacturing effort required for the production and assembly of the carbon fiber sleeve
Zur Debatte über die Einhegung eines Cyberwars: Analyse militärischer Cyberaktivitäten im Krieg Russlands gegen die Ukraine
No full textDer Überfall Russlands auf die Ukraine und der sich anschließende Krieg haben neben vielen anderen sicherheitspolitischen Gewissheiten auch zum ersten Mal die Rolle des Cyberspace in einem offenen Angriffskrieg demonstriert und bedenkenswerte Entwicklungen offenbart. Ziel dieses Beitrags ist es, die militärischen Aktivitäten im Cyberspace im Rahmen des Krieges Russlands gegen die Ukraine auf der Grundlage der öffentlich verfügbaren Informationen zu analysieren und im Hinblick auf die bis dato gängigen Vorstellungen eines Cyberwars zu bewerten. Darauf aufbauend werden mögliche Schlussfolgerungen betrachtet, zum einen mit Blick auf die zukünftige Bedeutung von Cyberaktivitäten für Russland, hinsichtlich des generellen militärischen Einsatzes von Cyberwirkmitteln und dessen weiterer Entwicklung, und in Bezug auf zukünftige internationale Debatten zur Einhegung von Cyberwars und des schädigenden Einsatzes von Cyberwirkmitteln
„Diego ist tot, es lebe Diego!“ – Soziologische Beobachtungen zur ungebrochenen Popularität Maradonas in Argentinien
No full textIm November 2020 starb Diego Armando Maradona. Das öffentliche Trauergeschehen und die Kommunikation in Reaktion auf seinen Tod verdeutlichen den außerordentlichen Symbolwert Maradonas in Argentinien auf besondere Weise. Betrachtet man jedoch die Vielzahl an Eskapaden, Regelverstößen, Gesetzesbrüchen und sonstigen Grenzüberschreitungen Maradonas, erscheinen seine fast ungebrochene Popularität und regelrecht sakrale Überhöhung zu Lebzeiten und über den Tod hinaus in einem anderen Licht. Neben seinen beiden Dopingfällen, Schlägereien auf dem Fußballplatz oder obszönen Gesten gegen sportliche Kontrahenten ist gerade auch die Liste seiner außersportlichen Verfehlungen lang. Erklärungsbedürftig ist dabei nicht nur, wie Maradona trotz aller Skandale Held bleiben konnte, sondern auch, in welchem Maße die Widersprüche, Ambivalenzen und Unzulänglichkeiten seinen Heldenstatus erst erzeugten. Aus diesem Grund werden im vorliegenden Beitrag die Leitsemantiken, Legitimationsrhetoriken, Neutralisierungstechniken, Rechtfertigungsgeschichten und sonstigen Präfigurationen identifiziert, die im allgemeinen Reden über Maradona wiederkehrend auftauchen. Es wird gezeigt, wie Gemeinschaftsfiktionen, Protestsymbole, Geniekonzept, Opfernarrative und Gottessemantik seinen Heldenstatus kommunikativ immunisieren, kontrafaktisch stabilisieren und zusätzlich befördern
Epistemic bricolage: Hans-Jörg Rheinberger: Spalt und Fuge: Eine Phänomenologie des Experiments. Frankfurt: Suhrkamp, 2021, 289pp, 22€ PB
No full textThere are two things one can count on in Hans-Jörg Rheinberger’s books, including this latest one, Spalt und Fuge: Eine Phänomenologie des Experiments (Split and Joint: A Phenomenology of Experiment). First, they cultivate the reader’s sensibility for the phenomenology or “micro-epistemology” (Bachelard’s term) of experimentation. Second, they operate with philosophically provocative assumptions. Here, one of these provocations appears early on, with a critique of Latour’s concept of “technoscience” which Rheinberger takes to imply the identification of science and technology: “I will show that it is worth our while to distinguish rather than blur the technological and epistemological aspects of the sciences, and to study their interplay. This will render visible how the technical (Technisches) and the epistemic (Epistemisches) condition and promote each other—and how precisely through this they reaffirm the differences between them” (19)
Turning a blind eye on the black sheep: when are voters loyal to corrupt politicians?
No full textWhen do voters turn a blind eye on corrupt politicians? Recent research suggests that voters might be willing to support corrupt politicians due to a lack of a ‘viable and clean alternative,’ i.e., voters prefer supporting a corrupt politician when the alternative is to support a politician who takes a fundamentally different policy stance. Following this argument, it has also been argued that especially corrupt politicians from radical parties are less likely to be punished by their voters as these voters are more hostile toward other parties. In other words, voters of radical parties are more likely to lack viable alternatives. Based on a survey experiment conducted in Germany, we put these hypotheses to an empirical test. We find evidence for the expected patterns. Supporters of radical parties are indeed less likely to switch their vote to a different party. However, our experiment also shows that this is because voters of radical parties are more likely to lack a viable alternative. When supporters of radical parties evaluate a clean alternative favorable, they are just as likely as voters of mainstream parties to switch away from the corrupt candidate. Finally, we show how strengths of partisan attachment affect voting for corrupt candidates
Quasi-real-time range monitoring by in-beam PET: a case for ¹⁵O
Full text linkA fast and reliable range monitoring method is required to take full advantage of the high linear energy transfer provided by therapeutic ion beams like carbon and oxygen while minimizing damage to healthy tissue due to range uncertainties. Quasi-real-time range monitoring using in-beam positron emission tomography (PET) with therapeutic beams of positron-emitters of carbon and oxygen is a promising approach. The number of implanted ions and the time required for an unambiguous range verification are decisive factors for choosing a candidate isotope. An experimental study was performed at the FRS fragment-separator of GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany, to investigate the evolution of positron annihilation activity profiles during the implantation of ¹⁴O and ¹⁵O ion beams in a PMMA phantom. The positron activity profile was imaged by a dual-panel version of a Siemens Biograph mCT PET scanner. Results from a similar experiment using ion beams of carbon positron-emitters ¹¹C and ¹⁰C performed at the same experimental setup were used for comparison. Owing to their shorter half-lives, the number of implanted ions required for a precise positron annihilation activity peak determination is lower for ¹⁰C compared to ¹¹C and likewise for ¹⁴O compared to ¹⁵O, but their lower production cross-sections make it difficult to produce them at therapeutically relevant intensities. With a similar production cross-section and a 10 times shorter half-life than ¹¹C, ¹⁵O provides a faster conclusive positron annihilation activity peak position determination for a lower number of implanted ions compared to ¹¹C. A figure of merit formulation was developed for the quantitative comparison of therapy-relevant positron-emitting beams in the context of quasi-real-time beam monitoring. In conclusion, this study demonstrates that among the positron emitters of carbon and oxygen, ¹⁵O is the most feasible candidate for quasi-real-time range monitoring by in-beam PET that can be produced at therapeutically relevant intensities. Additionally, this study demonstrated that the in-flight production and separation method can produce beams of therapeutic quality, in terms of purity, energy, and energy spread
High-throughput synthesis of CeO₂ nanoparticles for transparent nanocomposites repelling Pseudomonas aeruginosa biofilms
Full text linkPreventing bacteria from adhering to material surfaces is an important technical problem and a major cause of infection. One of nature’s defense strategies against bacterial colonization is based on the biohalogenation of signal substances that interfere with bacterial communication. Biohalogenation is catalyzed by haloperoxidases, a class of metal-dependent enzymes whose activity can be mimicked by ceria nanoparticles. Transparent CeO₂/polycarbonate surfaces that prevent adhesion, proliferation, and spread of Pseudomonas aeruginosa PA14 were manufactured. Large amounts of monodisperse CeO₂ nanoparticles were synthesized in segmented flow using a high-throughput microfluidic benchtop system using water/benzyl alcohol mixtures and oleylamine as capping agent. This reduced the reaction time for nanoceria by more than one order of magnitude compared to conventional batch methods. Ceria nanoparticles prepared by segmented flow showed high catalytic activity in halogenation reactions, which makes them highly efficient functional mimics of haloperoxidase enzymes. Haloperoxidases are used in nature by macroalgae to prevent formation of biofilms via halogenation of signaling compounds that interfere with bacterial cell–cell communication (“quorum sensing”). CeO₂/polycarbonate nanocomposites were prepared by dip-coating plasma-treated polycarbonate panels in CeO₂ dispersions. These showed a reduction in bacterial biofilm formation of up to 85% using P. aeruginosa PA14 as model organism. Besides biofilm formation, also the production of the virulence factor pyocyanin in is under control of the entire quorum sensing systems P. aeruginosa. CeO₂/PC showed a decrease of up to 55% in pyocyanin production, whereas no effect on bacterial growth in liquid culture was observed. This indicates that CeO₂ nanoparticles affect quorum sensing and inhibit biofilm formation in a non-biocidal manner
Sphagnoid spores as tracers of environmental and climatic changes in peatland habitats of the early Eocene
Full text linkPeat mosses have been an important part of the lignite forming vegetation in the early Eocene of the Helmstedt Lignite Mining District. Three genera of Sphagnum-type spores can be distinguished: Tripunctisporis, Distancoraesporis and Sphagnumsporites. The distribution of these sphagnoid spores is traced through seven lignite seams including most of the known hyperthermal events from the PETM to the EECO. In general, Sphagnum-type spores increase in importance from base to top in each seam as a result of acidification and nutrient depletion during peat accumulation. The proportion of Tripunctisporis increases from Main Seam to Seam 6. The lower three seams are characterized by assemblages typical for coastal plain swamp forests including tree stumps and charcoal in distinct layers and lenses. The upper seams, in which Tripunctisporis is dominant and woody material is rare, are thin-bedded with charcoal in numerous thin drapes on bedding planes. The palynomorph assemblages here indicate a low growing mainly herbaceous vegetation typical of ombrogenous bogs. The change from topogenous swamp forests to open ombrogenous bogs takes place along with the hyperthermals of the early Eocene from the PETM to the EECO. The change from a swamp forest to a shrub forest in the middle of the Main Seam coincides with the isotope excursion of the PETM. Similar changes in other seams independent of thermal events indicate that thermal events merely amplify changes in vegetation, which are primarily imposed by edaphic constraints. It is rather the rapid accumulation of hyperthermals during the EECO that exerts sufficient environmental stress to fundamentally alter the peat forming vegetation