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Die Klausur: VWL
(2016)
Die Festsetzungspraxis des GKV-Spitzenverbands im Festbetragswesen - eine kritische Bestandsaufnahme
(2016)
The analysis of Δ9-tetrahydrocannabinol (THC) and its metabolites 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-THC), and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) from blood serum is a routine task in forensic toxicology laboratories. For examination of consumption habits, the concentration of the phase I metabolite THC-COOH is used. Recommendations for interpretation of analysis values in medical-psychological assessments (regranting of driver’s licenses, Germany) include threshold values for the free, unconjugated THC-COOH. Using a fully automated two-step liquid-liquid extraction, THC, 11-OH-THC, and free, unconjugated THC-COOH were extracted from blood serum, silylated with N-methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA), and analyzed by GC/MS. The automation was carried out by an x-y-z sample robot equipped with modules for shaking, centrifugation, and solvent evaporation. This method was based on a previously developed manual sample preparation method. Validation guidelines of the Society of Toxicological and Forensic Chemistry (GTFCh) were fulfilled for both methods, at which the focus of this article is the automated one. Limits of detection and quantification for THC were 0.3 and 0.6 μg/L, for 11-OH-THC were 0.1 and 0.8 μg/L, and for THC-COOH were 0.3 and 1.1 μg/L, when extracting only 0.5 mL of blood serum. Therefore, the required limit of quantification for THC of 1 μg/L in driving under the influence of cannabis cases in Germany (and other countries) can be reached and the method can be employed in that context. Real and external control samples were analyzed, and a round robin test was passed successfully. To date, the method is employed in the Institute of Legal Medicine in Giessen, Germany, in daily routine. Automation helps in avoiding errors during sample preparation and reduces the workload of the laboratory personnel. Due to its flexibility, the analysis system can be employed for other liquid-liquid extractions as well. To the best of our knowledge, this is the first publication on a comprehensively automated classical liquid-liquid extraction workflow in the field of forensic toxicological analysis.
Design of an Active Multispectral SWIR Camera System for Skin Detection and Face Verification
(2016)
Biometric face recognition is becoming more frequently used in different application scenarios. However, spoofing attacks with facial disguises are still a serious problem for state of the art face recognition algorithms. This work proposes an approach to face verification based on spectral signatures of material surfaces in the short wave infrared (SWIR) range. They allow distinguishing authentic human skin reliably from other materials, independent of the skin type. We present the design of an active SWIR imaging system that acquires four-band multispectral image stacks in real-time. The system uses pulsed small band illumination, which allows for fast image acquisition and high spectral resolution and renders it widely independent of ambient light. After extracting the spectral signatures from the acquired images, detected faces can be verified or rejected by classifying the material as "skin" or "no-skin". The approach is extensively evaluated with respect to both acquisition and classification performance. In addition, we present a database containing RGB and multispectral SWIR face images, as well as spectrometer measurements of a variety of subjects, which is used to evaluate our approach and will be made available to the research community by the time this work is published.
UX-Professionals stehen vor der Aufgabe ihre Fertigkeiten und Kenntnisse kontinuierlich auszubauen. Eine Möglichkeit dies zu tun sind Communities of Practice, also Gemeinschaften von Personen mit ähnlichen Aufgaben und Schwerpunkten sowie einem gemeinsamen Interesse an Lösungen. Sie agieren weitgehend selbstorganisiert und dienen dem Austausch und der gegenseitigen Unterstützung. So entstehen ein gemeinsamer Wissensschatz sowie ein Netzwerk zwischen allen UX-Interessierten. Der Aufbau einer Community of Practice für UX-Professionals wurde in einem mittelständigen Unternehmen über 18 Monate begleitet und ausgewertet. Die Ergebnisse führten zu Handlungsempfehlungen, um Hindernisse beim Aufbau zu reduzieren und einen Mehrwert für alle Beteiligten herbeizuführen.
Die für den deutschen Glücks- und Gewinnspielmarkt derzeit geltenden rechtlichen und ordnungspolitischen Rahmenbedingungen führen dazu, dass sich der nicht-regulierte Markt deutlich zu Lasten des regulierten Marktes ausweitet, was negative volkswirtschaftliche und soziale Effekte zur Folge hat. Ziel der Politik sollte es sein, einen möglichst großen Teil des bis dato nicht-regulierten Marktes (Grau- und Schwarzmarkt) in einen geregelten Rahmen zu überführen.
Getrieben durch kleiner und günstiger werdende Sensoren und der damit verbundenen Messbarmachung immer weiter reichender Teile des Alltages, hat sich die Gestaltung von Verbrauchsvisualisierunen bzw. Verbrauchsfeedbacksystemen zur Unterstützung von nachhaltigem Verhalten zu einem sehr aktiven Forschungsfeld entwickelt.
Kleinere, günstigere und effizientere Sensoren und Aktoren sowie Funkprotokolle haben dazu geführt, dass Smart Home Produkte in zunehmend auch für den privaten Massenmarkt erschwinglich werden. Damit stehen Hersteller und Anbieter vor der Herausforderung, komplexe cyber-physische Systeme für Jedermann handhabbar zu gestalten. Es fehlen allerdings empirische Erkenntnisse über die Rolle von Smart Home im Alltag. Wir präsentieren Ergebnisse aus einer Living Lab Studie, in der 14 Haushalte mit einer am Markt erhältlichen Smart Home Nachrüstlösung ausgestattet und über neun Monate empirisch begleitet wurden. Anhand der Analyse von Interviews, Beobachtungen und Co-Design Workshops in den Phasen der Produktauswahl, Installation, Konfiguration und längerfristigen Nutzung zeigen wir Herausforderungen und Potentiale von Smart Home Systemen auf. Unsere Erkenntnisse deuten darauf hin, dass das Smart Home immer noch von technischen Details dominiert wird. Zugleich fehlen Nutzern angemessene Steuerungs- und Kontrollmöglichkeiten, um weiterhin die Entscheidungshoheit im eigenen Zuhause zu behalten.
During the last 50 years, a broad range of visible light curing resin based composites (VLC RBC) was developed for restorative applications in dentistry. Correspondingly, the technologies of light curing units (LCU) have changed from UV to visible blue light, and there from quartz tungsten halogen over plasma arc to LED LCUs increasing their light intensity significantly. In this thesis, the influence of the curing conditions in terms of irradiance, exposure time and irradiance distribution of LCU on reaction kinetics as well as corresponding mechanical and viscoelastic properties were investigated.
3D-Printing is an efficient method in the field of additive manufacturing. In order to optimize the properties of manufactured parts it is essential to adapt the curing behavior of the resin systems with respect to the requirements. Thus, effects of resin composition, e.g. due to different additives such as thickener and curing agents, on the curing behavior have to be known. As the resin transfers from a liquid to a solid glass the time dependent ion viscosity was measured using DEA with flat IDEX sensors. This allows for a sensitive measurement of resin changes as the ion viscosity changes two to four decades. The investigated resin systems are based on the monomers styrene and HEMA. To account for the effects of copolymerization in the calculation of the reaction kinetics it was assumed that the reaction can be considered as a homo-polymerization having a reaction order n?1. Then the measured ion viscosity curves are fitted with the solution of the reactions kinetics - the time dependent degree of conversion (DC-function) - for times exceeding the initiation phase representing the primary curing. The measured ion viscosity curves can nicely be fitted with the DC-function and the determined fit parameters distinguish distinctly between the investigated resin compositions.
Large sections of the German society are able to buy and consume meat on a daily basis due to progress in the agri-food sector. However, the way meat is produced, traded and consumed increasingly has become an issue that is controversially discussed by the media, non-governmental organisations (NGOs), lobbyists, the industry itself and consumers – often with a negative connotation. The meat industry reacts to this. By creating information campaigns and animal welfare initiatives it aims to stress that it is going to take its corporate social responsibilities (CSR) for consumers and animal welfare seriously. But, the industry’s actions are still criticised as being not sufficient to improve animal welfare levels significantly. Much of this criticism can be observed in online news portals, where articles about the issue get published and commented by readers. This makes online portals a valuable source for information that is to be tapped in this study. It aims to better understand the multifaceted discussions concerning animal welfare initiatives in online portals. By applying qualitative content analysis and web mining techniques to a sample of documents taken from three major German news sites it can be shown that online discussions refer to various aspects of sustainability and corporate social responsibility. Findings also indicate that the discussions are framed by financial aspects.
Der Beitrag stellt auf Basis einer Literaturanalyse den aktuellen Forschungsstand zu Controlling Shared Service Centern dar. Darauf aufbauend wird dieser um die praktischen Erfahrungen bei der Deutschen Telekom ergänzt. Insbesondere der Prozess des Risikomanagements wird hierzu auf seine Eignung für Shared Services auf Grundlage der etwa dreijährigen Erfahrungen des Unternehmens geprüft.
Salts and proteins comprise two of the basic molecular components of biological materials. Kosmotropic/chaotropic co-solvation and matching ion water affinities explain basic ionic effects on protein aggregation observed in simple solutions. However, it is unclear how these theories apply to proteins in complex biological environments and what the underlying ionic binding patterns are. Using the positive ion Ca2+ and the negatively charged membrane protein SNAP25, we studied ion effects on protein oligomerization in solution, in native membranes and in molecular dynamics (MD) simulations. We find that concentration-dependent ion-induced protein oligomerization is a fundamental chemico-physical principle applying not only to soluble but also to membrane-anchored proteins in their native environment. Oligomerization is driven by the interaction of Ca2+ ions with the carboxylate groups of aspartate and glutamate. From low up to middle concentrations, salt bridges between Ca2+ ions and two or more protein residues lead to increasingly larger oligomers, while at high concentrations oligomers disperse due to overcharging effects. The insights provide a conceptual framework at the interface of physics, chemistry and biology to explain binding of ions to charged protein surfaces on an atomistic scale, as occurring during protein solubilisation, aggregation and oligomerization both in simple solutions and membrane systems.
Mobilitäts- und Nachhaltigkeitsforscher sehen sich bei der Erforschung des Mobilitätsverhaltens von Personen mit einer bunten Palette an Erhebungsmethoden konfrontiert. Erweitert wird diese Vielfalt in der letzten Zeit durch die Möglichkeit, dieses Verhalten direkt über die Smartphones der Probanden zu erfassen. Um die Auswahl geeigneter Methoden zu erleichtern, liefert die vorliegende Literaturstudie einen detaillierten Überblick zu Fragestellungen, Daten und Erhebungsmethoden, die im Bereich der Mobilitätsforschung zur Erfassung von Alltagsmobilität eingesetzt werden.