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Sensitizing students to information security and privacy awareness with analogue gamification
No full textMany studies and investigations in the area of information security reveal a careless handling of sensitive data and insufficient information security awareness. Despite increasing digitization, which has a huge impact on society as a whole, we tend not to pay enough attention to the risks associated with it. But research shows that the mere transfer of knowledge is not enough to cause behavioural changes. Rather, a systemic approach that can bring about the necessary emotionalization and reflection through analogue game-based learning is helpful.Viele Studien und Untersuchungen im Bereich der Informationssicherheit zeigen einen nachlässigen Umgang mit sensiblen Daten und ein unzureichendes Bewusstsein der Menschen für die Informationssicherheit. Trotz der zunehmenden Digitalisierung, die die Gesellschaft insgesamt stark beeinflusst, neigen wir dazu, den damit verbundenen Risiken nicht genügend Aufmerksamkeit zu schenken. Sensibilisierung der Menschen ist nötig und soll zu ihren Verhaltensänderungen in der IT-Sicherheit führen. Untersuchungen zeigen jedoch, dass der bloße Wissenstransfer nicht ausreicht, um Verhaltensänderungen zu bewirken. Vielmehr ist ein systemischer Ansatz hilfreich, der durch analoges, spielbasiertes Lernen die notwendige Emotionalisierung für Austausche von Erfahrung und eine Reflexion der Menschen herbeiführen kann. Digitales, spielbasiertes Lernen in der IT-Sicherheit sollte ebenfalls die Emotionalisierung der Menschen adressieren
The in vivo mechanics of the magnetotactic backbone as revealed by correlative FLIM-FRET and STED microscopy
No full textProtein interaction and protein imaging strongly benefit from the advancements in time-resolved and superresolution fluorescence microscopic techniques. However, the techniques were typically applied separately and ex vivo because of technical challenges and the absence of suitable fluorescent protein pairs. Here, we show correlative in vivo fluorescence lifetime imaging microscopy Förster resonance energy transfer (FLIM-FRET) and stimulated emission depletion (STED) microscopy to unravel protein mechanics and structure in living cells. We use magnetotactic bacteria as a model system where two proteins, MamJ and MamK, are used to assemble magnetic particles called magnetosomes. The filament polymerizes out of MamK and the magnetosomes are connected via the linker MamJ. Our system reveals that bacterial filamentous structures are more fragile than the connection of biomineralized particles to this filament. More importantly, we anticipate the technique to find wide applicability for the study and quantification of biological processes in living cells and at high resolution
Raman lasers for trace gas detection
No full textThe emission of commercial solid-state lasers is shifted by Raman lasers to selected wavelengths suitable for trace gas detection. High power Raman lasers based on Ba(NO3)2, diamond and silicon detect CO2, O3 and H2O. Raman lasers base on the physical effect of stimulated Raman scattering. Two new Raman crystals (Spodumene and LuAlO3) are investigated and their SRS-spectra is shown
A new triple system DNA-Nanosilver-Berberine for cancer therapy
No full textThe isoquinoline quaternary alkaloid Berberine possesses a variety of pharmacological properties that suggests its promising application for an anticancer delivery system design utilizing its ability to intercalate DNA. In the current work, we have investigated the effects of Berberine on the human T cell leukemia cell line in vitro. Fluorescent microscopy of leukemic cells revealed Berberine nuclear localization. The results showed that Berberine inhibited leukemic cell growth in a time- and dose-dependent manner, that was associated with reactive oxygen species production intensification and caspase 3/7 activity increase with followed apoptosis induction. Berberine was used as a toxic and phototoxic agent for triple system synthesis along with DNA as a carrier and nanosilver as a plasmonic accelerator of Berberine electronic transitions and high energy emission absorbent centers. The proposed method allows to obtain the complex of DNA with Berberine molecules and silver nanoparticles. The optical properties of free components as well as their various combinations, including the final triple system DNA-Nanosilver-Berberine, were investigated. Obtained results support the possibility to use the triple system DNA-Nanosilver-Berberine as an alternative therapeutic agent for cancer treatment
The Role of Substrate Temperature and Magnetic Filtering for DLC by Cathodic Arc Evaporation
Get PDFDiamond-like carbon (DLC) films were deposited using two different types of high current arc evaporation. The first process used a magnetic particle filter to remove droplets from the plasma. For the second process, the samples were put into a metallic cage which was placed directly above the plasma source. For both processes, we varied the substrate temperature from 21 to 350 °C in order to investigate the temperature effect. The samples were characterized using SEM, AFM, XPS, Raman Spectroscopy, Ellipsometry, Photometry, and Nano Indentation in order to compare both methods of deposition and provide a careful characterization of such DLC films. We found that the sp3 content and the hardness can be precisely adjusted by changing the substrate temperature. Furthermore, in the case of unfiltered deposition, the optical constants can be shifted in the direction of higher absorbance in order to produce black and hard carbon coatings
Preservation Planning for Digital Audio-Visual Material at the German National Library of Science and Technology (TIB) – Developing a Catalogue of Criteria and a Migration Plugin
Get PDFThe German Nation Library of Science and Technology (TIB) runs a digital archive in order to preserve its digital holdings which consists amongst others of audio-visual material. In order to identify obsolete audio-visual file formats a catalogue of criteria is developed and file formats which represent the majority of TIB’s audio-visual holdings are examined. The assessment reveals that the examined file formats are not a preferred file format for digital preservation, but on the other hand they are not at risk to become obsolete to TIB’s designated community. Furthermore, a migration plugin for the digital archive’s software environment is developed and successfully deployed. The migration plugin can be used during preservation planning in order to migrate the examined formats into TIB’s chosen archival file format if a migration becomes necessary
The Future of Layer-by-Layer Assembly: A Tribute to ACS Nano Associate Editor Helmuth Möhwald
No full textLayer-by-layer (LbL) assembly is a widely used tool for engineering materials and coatings. In this Perspective, dedicated to the memory of ACS Nano associate editor Prof. Dr. Helmuth Möhwald, we discuss the developments and applications that are to come in LbL assembly, focusing on coatings, bulk materials, membranes, nanocomposites, and delivery vehicles
Erweiterung eines landmarkenbasierten Innenraumortungsverfahrens für Mobilgeräte mit ARCore
No full textDie Lokalisierung in Innenräumen, die sich nicht auf Satellitennavigation wie GPS verlassen kann, ist nach wie vor eine Herausforderung. Viele Methoden zur Lokalisierung in Innenräumen beruhen auf Funksignalen oder anderen Sendern (z.B. Infrarot), die eine kostenintensive Infrastruktur erfordern, die in einem Gebäude installiert werden muss. Außerdem sind diese Techniken ungenau, wenn Reflexionen der Signale in einem Gebäude auftreten. Die Forschungsgruppe Telematik der TH Wildau hat für diese Problemstellung ein optisches Verfahren zur Innenraumlokalisierung entwickelt, das die Kamera eines mobilen Geräts verwendet. Dieser Ansatz erfordert nur die Verfügbarkeit von mehreren identifizierbaren Landmarken, die kostengünstig in einem Gebäude installiert werden können. In diesem Beitrag soll eine Möglichkeit vorgestellt werden, dieses landmarkenbasierte Verfahren mit der Augmented Reality-Bibliothek ARCore von Google zu erweitern, um eine kontinuierliche Positionsermittlung zu ermöglichen, auch wenn vorübergehend keine Landmarken durch die Gerätekamera erfasst werden können.Indoor localization, which cannot rely on satellite navigation such as GPS, remains a challenge. Many indoor localization methods depend on radio signals or other transmitters (e.g. infrared) that require a costly infrastructure to be installed in a building. In addition, these techniques are inaccurate when reflections of the signals occur in a building. The telematics research group at TH Wildau has developed an optical method for indoor localization for this problem that uses the camera of a mobile device. This approach only requires the availability of several identifiable landmarks that can be installed cost-effectively in a building. In this article, a way is presented to extend this landmark based method with Google's Augmented Reality library ARCore to enable continuous position tracking even if no landmarks can be captured by the device camera temporarily
Comparative Study of Nano-Slot Silicon Waveguides Covered by Dye Doped and Undoped Polymer Cladding
No full textNonlinear optical dyes doped in optical polymer matrices are widely used for electro-optical devices. Linear optical properties change with dye concentration, which leads to a change in modal properties, especially in nano-structured integrated waveguides such as silicon slot-waveguides. Here, we investigate the influence of a nonlinear optical dye on the performance of a silicon-organic hybrid slot-waveguide. A simulation study of the modal and optical confinement properties is carried out and dependence of the structural parameters of the slot-waveguide and the organic cladding material is taken into account. As cladding material, a guest-host polymer system is employed comprising the nonlinear optical dye Disperse Red 1 (DR1) doped in a poly[methyl methacrylate] (PMMA) matrix. The refractive indices of doped and undoped PMMA were deduced from ellipsometric data. We present a guideline for an optimized slot-waveguide design for the fabrication in silicon-on-insulator technology giving rise to scalable, high-performance integrated electro-optical modulators
On-Chip Dispersion Measurement of the Quadratic Electro-Optic Effect in Nonlinear Optical Polymers Using a Photonic Integrated Circuit Technology
Get PDFA novel method to determine the dispersion of the quadratic electro-optic effect in nonlinear optical materials by using a silicon-on-insulator microring resonator is presented. The microring consists of a silicon slot waveguide enabling large dc electric field strength at low applied voltages. The dispersion of third-order hyperpolarizability of a linear conjugated dye is approximated by using a two-level model for the off-resonant spectral region. As an example, the dispersion of the resonance wavelength of the resonator filled with a dye doped polymer was measured in dependence of the applied dc voltage. The polymer was poly (methylmethacrylate) doped with 5 wt% disperse red 1 (DR1), and the measurements have been carried out at the telecommunication wavelength band around 1550 nm (optical C-band). The described measurements represent a new technique to determine the dispersion of the third-order susceptibility and molecular hyperpolarizability of the material filled into the slot of the ring-resonator