Interactive Science Fiction Prototyping in Virtual Worlds: Fundamentals and Applications

Science Fiction Prototyping (SFP) is a powerful tool to imagine, explore, and exploit future technologies, science, and environments and it can be a valuable asset for education, multimedia, and research. This article explores SFP in interactive, flexible, immersive, and collaborative settings, which introduced as Interactive Science Fiction Prototyping (ISFP) and allows new forms of experiencing and reflecting on prototypes. We investigate how to integrate the ISFP process into an existing collaborative virtual world platform and outline required integration steps. Furthermore, we discuss different application scenarios for ISFP in educational, artistic, and business domains and conclude with future ideas and challenges to explore modern scientific ideas

Direct electrical modulation of surface response in a single plasmonic nanoresonator

Classical electrodynamics describes the optical response of macroscopic systems, where the boundaries between materials is treated as infinitesimally thin. However, due to the quantum nature of electrons, interfaces acquires a finite thickness. To include non-classical surface effects in the framework of Maxwell's equations, surface-response functions can be introduced, also known as Feibelman $d$-parameters. Surface response impacts systems with strong field localization at interfaces, which is encountered in noble metal nanoparticles supporting surface plasmon polaritons. However, studying surface response is challenging as it necessitates sub-nanometer control of geometric features, e.g. the gap size in a dimer antenna, while minimizing uncertainties in morphology. In contrast, electrical gating is convenient since the static screening charges are confined exclusively to the surface, which alleviates the need for precise control over the morphology. Here, we study the perturbation of Feibelman $d$-parameters by direct electric charging of a single plasmonic nanoresonator and investigate the resulting changes of the resonance in experiment and theory. The measured change of the resonance frequency matches the theory by assuming a perturbation of the tangential surface current. However, we also observe an unforeseen narrowing in the resonance width when adding electrons to the surface of a plasmonic nanoresonator. These reduced losses cannot be explained by electron spill-out within the local-response approximation (LRA). Such an effect is likely caused by nonlocality and the anisotropy of the perturbed local permittivity. Our findings open up possibilities to reduce losses in plasmonic resonators and to develop ultrafast and extremely small electrically driven plasmonic modulators and metasurfaces by leveraging electrical control over non-classical surface effects.Comment: 10 pages, 3 figures, 15 pages Supplementar

In vivo investigation of open-pored magnesium scaffolds LAE442 with different coatings in an open wedge defect

The magnesium alloy LAE442 showed promising results as a bone substitute in numerous studies in non-weight bearing bone defects. This study aimed to investigate the in vivo behavior of wedge-shaped open-pored LAE442 scaffolds modified with two different coatings (magnesium fluoride (MgF2, group 1)) or magnesium fluoride/calcium phosphate (MgF2/CaP, group 2)) in a partial weight-bearing rabbit tibia defect model. The implantation of the scaffolds was performed as an open wedge corrective osteotomy in the tibia of 40 rabbits and followed for observation periods of 6, 12, 24, and 36 weeks. Radiological and microcomputed tomographic examinations were performed in vivo. X-ray microscopic, histological, histomorphometric, and SEM/EDS analyses were performed at the end of each time period. µCT measurements and X-ray microscopy showed a slight decrease in volume and density of the scaffolds of both coatings. Histologically, endosteal and periosteal callus formation with good bridging and stabilization of the osteotomy gap and ingrowth of bone into the scaffold was seen. The MgF2 coating favored better bridging of the osteotomy gap and more bone-scaffold contacts, especially at later examination time points. Overall, the scaffolds of both coatings met the requirement to withstand the loads after an open wedge corrective osteotomy of the proximal rabbit tibia. However, in addition to the inhomogeneous degradation behavior of individual scaffolds, an accumulation of gas appeared, so the scaffold material should be revised again regarding size dimension and composition

In vivo investigation of open-pored magnesium scaffolds LAE442 with different coatings in an open wedge defect

The magnesium alloy LAE442 showed promising results as a bone substitute in numerous studies in non-weight bearing bone defects. This study aimed to investigate the in vivo behavior of wedge-shaped open-pored LAE442 scaffolds modified with two different coatings (magnesium fluoride (MgF2, group 1)) or magnesium fluoride/calcium phosphate (MgF2/CaP, group 2)) in a partial weight-bearing rabbit tibia defect model. The implantation of the scaffolds was performed as an open wedge corrective osteotomy in the tibia of 40 rabbits and followed for observation periods of 6, 12, 24, and 36 weeks. Radiological and microcomputed tomographic examinations were performed in vivo. X-ray microscopic, histological, histomorphometric, and SEM/EDS analyses were performed at the end of each time period. µCT measurements and X-ray microscopy showed a slight decrease in volume and density of the scaffolds of both coatings. Histologically, endosteal and periosteal callus formation with good bridging and stabilization of the osteotomy gap and ingrowth of bone into the scaffold was seen. The MgF2 coating favored better bridging of the osteotomy gap and more bone-scaffold contacts, especially at later examination time points. Overall, the scaffolds of both coatings met the requirement to withstand the loads after an open wedge corrective osteotomy of the proximal rabbit tibia. However, in addition to the inhomogeneous degradation behavior of individual scaffolds, an accumulation of gas appeared, so the scaffold material should be revised again regarding size dimension and composition

Comparison of two pore sizes of LAE442 scaffolds and their effect on degradation and osseointegration behavior in the rabbit model

The magnesium alloy LAE442 emerged as a possible bioresorbable bone substitute over a decade ago. In the present study, using the investment casting process, scaffolds of the Magnesium (Mg) alloy LAE442 with two different and defined pore sizes, which had on average a diameter of 400 μm (p400) and 500 μm (p500), were investigated to evaluate degradation and osseointegration in comparison to a ß‐TCP control group. Open‐pored scaffolds were implanted in both greater trochanter of rabbits. Ten scaffolds per time group (6, 12, 24, and 36 weeks) and type were analyzed by clinical, radiographic and μ‐CT examinations (2D and 3D). None of the scaffolds caused adverse reactions. LAE442 p400 and p500 developed moderate gas accumulation due to the Mg associated in vivo corrosion, which decreased from week 20 for both pore sizes. After 36 weeks, p400 and p500 showed volume decreases of 15.9 and 11.1%, respectively, with homogeneous degradation, whereas ß‐TCP lost 74.6% of its initial volume. Compared to p400, osseointegration for p500 was significantly better at week 2 postsurgery due to more frequent bone‐scaffold contacts, higher number of trabeculae and higher bone volume in the surrounding area. No further significant differences between the two pore sizes became apparent. However, p500 was close to the values of ß‐TCP in terms of bone volume and trabecular number in the scaffold environment, suggesting better osseointegration for the larger pore size

Legitimacy in the Multilevel European Polity

In order to be simultaneously effective and liberal, governments must normally be able to count on voluntary compliance – which, in turn, depends on the support of socially shared legitimacy beliefs. In Western constitutional democracies, such beliefs are derived from the distinct but coexistent traditions of “republican” and “liberal” political philosophy. When judged by these criteria, the European Union – if considered by itself – appears as a thoroughly liberal polity which, however, lacks all republican credentials. But this view (which seems to structure the debates about the “European democratic deficit”) ignores the multilevel nature of the European polity, where the compliance of citizens is requested, and needs to be legitimated by member states – whereas the Union appears as a “government of governments” which is entirely dependent on the voluntary compliance of its member states. What matters primarily, therefore, is the compliance-legitimacy relationship between the Union and its member states – which, however, is normatively constrained by the basic compliance-legitimacy relationship between member governments and their constituents. Given the high consensus requirements of European legislation, member governments could and should be able to assume political responsibility for European policies in which they had a voice, and to justify them in “communicative discourses” in the national public space. This is not necessarily true of “non-political” policy choices imposed by the European Court of Justice. By enforcing its “liberal” program of liberalization and deregulation, the ECJ may presently be undermining the “republican” bases of member-state legitimacy. Where this is the case, open non-compliance is a present danger, and political controls of judicial legislation may be called for.Um gleichzeitig effektiv und liberal sein zu können, ist staatliche Herrschaft auf freiwillige Folgebereitschaft angewiesen – die ihrerseits der Unterstützung durch sozial geteilte Legitimitätsüberzeugungen bedarf. In den demokratischen Verfassungsstaaten des Westens werden solche Überzeugungen aus den unterschiedlichen, aber komplementär zusammenwirkenden Traditionen der „republikanischen“ und der „liberalen“ politischen Philosophie hergeleitet. An diesen Kriterien gemessen erscheint die Europäische Union – wenn man sie für sich betrachtet – als eine „liberale“ politische Ordnung, der jedoch alle „republikanischen“ Legitimitätsmerkmale fehlen. Aber eine solche Sichtweise, die auch die derzeitige Diskussion über ein „europäisches Demokratiedefizit“ bestimmt, verkennt den Mehrebenencharakter des europäischen Gemeinwesens. In ihm sind es die Mitgliedstaaten, die Entscheidungen der Union gegenüber den eigenen Bürgern durchsetzen und auch legitimieren müssen, während es für die Union ihrerseits auf die freiwillige Folgebereitschaft ihrer Mitgliedstaaten ankommt. Dabei werden diese jedoch durch die normativen Grundlagen ihrer eigenen Legitimität begrenzt. Politische Entscheidungen auf europäischer Ebene setzen breiten Konsens voraus, und die Regierungen sollten sie deshalb auch gegenüber den eigenen Bürgern in „kommunikativen Diskursen“ vertreten und dafür die politische Verantwortung übernehmen können. Dies gilt jedoch nicht notwendigerweise auch für Entscheidungen der europäischen Politik, die im nichtpolitischen Modus ohne Beteiligung des Rates und des Parlaments vom Europäischen Gerichtshof bestimmt werden. Mit der gegenwärtigen Radikalisierung seines „liberalen“ Programms der Liberalisierung und Deregulierung des nationalen Rechts könnte der Gerichtshof in der Tat die „republikanischen“ Grundlagen der mitgliedstaatlichen Legitimität unterminieren. In diesem Falle könnte die Union sich nicht länger auf die Folgebereitschaft ihrer Mitgliedstaaten verlassen. Um diese Gefahr für die europäische Integration zu vermeiden, sollte eine stärkere politische Kontrolle der richterlichen Rechtsetzung erwogen werden.1 Legitimacy Republican and liberal legitimating discourses Constitutional democracies – and the EU? 2 Legitimacy in multilevel polities 3 Legitimating member state compliance Political modes of policy making Non-political policy making 4 The need for justification 5 The Court is pushing against the limits of justifiability 6 The liberal undermining of republican legitimacy 7 Needed: A political balance of community and autonomy Reference

Ubiquitous Web Application Development - A Framework for Understanding

E-commerce and m-commerce have dramatically boosted the demand for services which enable ubiquitous access. Ubiquity with its anytime/anywhere/anymedia nature requiring context-aware computing and personalisation calls for new engineering techniques supporting these kind of services. In this paper, we propose the notion of customisation as the uniform mechanism to provide the necessary flexibility with respect to both context-aware computing and personalisation. Customisation is realised in terms of a reflective architecture consisting of context, profile and customisation rule management

Ubiquitous Web Application Development - A Framework for Understanding

E-commerce and m-commerce have dramatically boosted the demand for services which enable ubiquitous access. Ubiquity with its anytime/anywhere/anymedia nature requiring contextaware computing and personalisation calls for new engineering techniques supporting these kind of services. In this paper, we propose the notion of customisation as the uniform mechanism to provide the necessary flexibility with respect to both contextaware computing and personalisation. Customisation is realised in terms of a reflective architecture consisting of context, profile and customisation rule management

Effect of pore size on tissue ingrowth and osteoconductivity in biodegradable Mg alloy scaffolds

Magnesium has mechanical properties similar to those of bone and is being considered as a potential bone substitute. In the present study, two different pore sized scaffolds of the Mg alloy LAE442, coated with magnesium fluoride, were compared. The scaffolds had interconnecting pores of either 400 (p400) or 500 µm (p500). ß-TCP served as control. Ten scaffolds per time group (6, 12, 24, 36 weeks) were implanted in the trochanter major of rabbits. Histological analyses, µCT scans, and SEM/EDX were performed. The scaffolds showed slow volume decreases (week 36 p400: 9.9%; p500: 7.5%), which were accompanied by uncritical gas releases. In contrast, ß-TCP showed accelerated resorption (78.5%) and significantly more new bone inside (18.19 ± 1.47 mm3). Bone fragments grew into p400 (0.17 ± 0.19 mm3) and p500 (0.36 ± 0.26 mm3), reaching the centrally located pores within p500 more frequently. In particular, p400 displayed a more uneven and progressively larger surface area (week 36 p400: 253.22 ± 19.44; p500: 219.19 ± 4.76 mm2). A better osseointegration of p500 was indicated by significantly more trabecular contacts and a 200 µm wide bone matrix being in the process of mineralization and in permanent contact with the scaffold. The number of macrophages and foreign body giant cells were at an acceptable level concerning resorbable biomaterials. In terms of ingrown bone and integrative properties, LAE442 scaffolds could not achieve the results of ß-TCP. In this long-term study, p500 appears to be a biocompatible and more osteoconductive pore size for the Mg alloy LAE442