Human Islet Microtissues as an In Vitro and an In Vivo Model System for Diabetes

Loss of pancreatic β-cell function is a critical event in the pathophysiology of type 2 diabetes. However, studies of its underlying mechanisms as well as the discovery of novel targets and therapies have been hindered due to limitations in available experimental models. In this study we exploited the stable viability and function of standardized human islet microtissues to develop a disease-relevant, scalable, and reproducible model of β-cell dysfunction by exposing them to long-term glucotoxicity and glucolipotoxicity. Moreover, by establishing a method for highly-efficient and homogeneous viral transduction, we were able to monitor the loss of functional β-cell mass in vivo by transplanting reporter human islet microtissues into the anterior chamber of the eye of immune-deficient mice exposed to a diabetogenic diet for 12 weeks. This newly developed in vitro model as well as the described in vivo methodology represent a new set of tools that will facilitate the study of β-cell failure in type 2 diabetes and would accelerate the discovery of novel therapeutic agents.     

Corrosion of anode current collectors in molten carbonate fuel cells

Corrosion of metallic parts is one of the life-time limiting factors in the molten carbonate fuel cell. In the reducing environment at the anode side of the cell, the corrosion agent is water. As anode current collector, a widely used material is nickel clad on stainless steel since nickel is stable in anode environment, but a cheaper material is desired to reduce the cost of the fuel cell stack. When using the material as current collector one important factor is a low resistance of the oxide layer formed between the electrode and the current collector in order not to decrease the cell efficiency. In this study, some candidates for anode current collectors have been tested in single cell molten carbonate fuel cells and the resistance of the oxide layer has been measured. Afterwards, the current collector was analysed in scanning electron microscope (SEM) equipped with energy dispersive spectrometer (EDS). The results show that the resistances of the formed oxide layers give a small potential drop compared to that of the cathode current collector.     

A Shape‐Induced Orientation Phase within 3D Nanocrystal Solids

When nanocrystals self assemble into ordered superstructures they form functional solids that may inherit the electronical properties of the single nanocrystals. To what extent these properties are enhanced depends on the positional and orientational order of the nanocrystals within the superstructure. Here, the formation of micrometer‐sized free‐standing supercrystals of faceted 20 nm Bi nanocrystals is investigated. The self‐assembly process, induced by nonsolvent into solvent diffusion, is probed in situ by synchrotron X‐ray scattering. The diffusion‐gradient is identified as the critical parameter for controlling the supercrystal‐structure as well as the alignment of the supercrystals with respect to the substrate. Monte Carlo simulations confirm the positional order of the nanocrystals within these superstructures and reveal a unique orientation phase: the nanocrystal shape, determined by the atomic Bi crystal structure, induces a total of 6 global orientations based on facet‐to‐facet alignment. This parallel alignment of facets is a prerequisite for optimized electronic and optical properties within designed nanocrystal solids.     

A study on LiCoO2-rich cathode materials for the MCFC based on the LiCoO2-LiFeO2-NiO ternary system

A study performed in LiCoO₂-rich LiCoO₂-LiFeO₂-NiO ternary materials for the molten carbonate fuel cell (MCFC) cathodes is reported in this paper. LiCoO₂-LiFeO₂-NiO ternary materials are considered as more viable alternatives to lithiated NiO, however, the work reported so far has mainly been focused on ternary compositions rich in LiFeO₂ or NiO. The present work was carried out by investigating the electrical conductivity and microstructural characteristics of the new materials first in the form of bulk pellets and then in ex situ sintered porous-gas-diffusion (PGD) cathodes. The material study reveals the ability of preparing LiCoO₂-LiFeO₂-NiO ternary compositions with adequate electrical conductivity by controlling the LiCoO₂ content. A bimodal pore structure, appropriate for the MCFC cathode, could be achieved in sintered cathodes prepared with fine powders and pore formers. Further, the cathode fabrication study indicates the nature of the compromise to be made between the electrical conductivity, phase purity, pore structure and porosity in optimization cathodes for MCFC application. The study shows the possibility of preparing LiCoO₂-rich LiCoO₂-LiFeO₂-NiO cathodes with promising electrical and pore structural characteristics for the MCFC.     

Approximate data instance matching: a survey

Approximate data matching is a central problem in several data management processes, such as data integration, data cleaning, approximate queries, similarity search and so on. An approximate matching process aims at defining whether two data represent the same real-world object. For atomic values (strings, dates, etc), similarity functions have been defined for several value domains (person names, addresses, and so on). For matching aggregated values, such as relational tuples and XML trees, approaches alternate from the definition of simple functions that combine values of similarity of record attributes to sophisticated techniques based on machine learning, for example. For complex data comparison, including structured and semistructured documents, existing approaches use both structure and data for the comparison, by either considering or not considering data semantics. This survey presents terminology and concepts that base approximated data matching, as well as discusses related work on the use of similarity functions in such a subject.     

Optimierung der Anodisierbarkeit bei Aluminiumautomatenlegierungen

Free-cutting aluminium alloys contain beside the typical strengthening alloying elements so called free-cutting phases which give benefits to the machining behaviour of the alloys. Compared to pure aluminium, they have lower melting points and less hardness. The third requirement in this context is their indissolubility in the aluminium matrix. Examples are Bi, Cd, In and Sn. For the commercial anodic treatment, most of the alloying elements are problematic. They could probably generate intermetallic phases in the anodic film, be in charge of building laminate layers, provoke the appearance of blisters, or produce other defects in the protecting layer. Current research about the anodization process at the Institute of Nonferrous Metallurgy, University of Leoben, covers a wide scope of topics, ranging from the machining processes to the final sealing step of anodic treatments and intends to optimize the whole product-chain with attention to sustainable requirements.     

Design,Synthesis and Biological Evaluation of Highly Potent Simplified Archazolids

The archazolids are potent antiproliferative compounds that have recently emerged as a novel class of promising anticancer agents. Their complex macrolide structures and scarce natural supply make the development of more readily available analogues highly important. Herein, we report the design, synthesis and biological evaluation of four simplified and partially saturated archazolid derivatives. We also reveal important structure-activity relationship data as well as insights into the pharmacophore of these complex polyketides.     

Designing social videogames for educational uses

In this paper we analyze the main areas of research into educational videogames and in the evolution of the technologies and design methodologies that are making these interactive systems increasingly natural, immersive and social. We present the design and development of a prototype for a collaborative educational videogame based on a Massively Multiplayer Online Role-Playing Game (MMORPG) engine for use in various educational contexts in (a) university education and (b) secondary education.