Indikatorenbasierte Evaluierung von Fischhabitaten in alpinen Fließgewässern

The EU Water Framework Directive commits member states to achieve good ecological status in all waterbodies. Artificial or heavily modified waterbodies must reach at least its good ecological potential. In view of these requirements, simple and feasible methods are required in order to evaluate habitat suitability for relevant target species in larger river reaches. Well-developed models for determining the relationship between stream flows and habitat for target species mainly based on micro- and meso-scale already exist. However, the application of such models is complex and time-consuming and consequently limited to relatively short river segments. The objective of this study is to develop a simplified applicable assessment model to evaluate habitat conditions for selected target fish. This model uses hydro-morphological indicators for the habitat assessment and relies on correlative relations between habitat suitability and hydro-morphological features of river stretches (average Froude-number, relative flow width, mean bed slope, relative water depth and flow velocity). The indicators were determined as reach-related averages, derived from 2D model simulations (hydraulic and habitat-specific). Particular emphasis was laid on using a wide range of river stretches with different hydro-morphological characteristics (hydrology, bed substratum, bed structures, degree of braiding, sinuosity of the river course, mean bed width and bed slope). As a result, a set of model equations enables the evaluation of fish habitat conditions in river stretches as a function of flow and morphology. The habitat suitability assessment focuses on four preselected target species: brown trout, European grayling and for low slope rivers common nase and barbel.     

BioPACE

While developing the specifications for electronically enabled Machine Readable Travel Documents, the ICAO paid significant attention to security aspects related to the digital information stored in this type of electronic document. This has resulted in Passive and Active Authentication, Basic Access Control and Extended Access Control. The goal of Basic Access Control (BAC) is preventing unauthorized access to the chip data stored on eMRTDs. The PACE protocol has been developed as a future-proof method to overcome the limitations of BAC and to replace BAC in the future. In this paper the BioPACE protocol is proposed as a supplement to the PACE protocol. Besides verifying if the document holder is indeed the rightful owner, the BioPACE protocol provides a higher convenience for the bearer of the document.     

Anonymous attestation with user-controlled linkability

This paper is motivated by the observation that existing security models for direct anonymous attestation (DAA) have problems to the extent that insecure protocols may be deemed secure when analysed under these models. This is particularly disturbing as DAA is one of the few complex cryptographic protocols resulting from recent theoretical advances actually deployed in real life. Moreover, standardization bodies are currently looking into designing the next generation of such protocols. Our first contribution is to identify issues in existing models for DAA and explain how these errors allow for proving security of insecure protocols. These issues are exhibited in all deployed and proposed DAA protocols (although they can often be easily fixed). Our second contribution is a new security model for a class of “pre-DAA scheme”, that is, DAA schemes where the computation on the user side takes place entirely on the trusted platform. Our model captures more accurately than any previous model the security properties demanded from DAA by the trusted computing group (TCG), the group that maintains the DAA standard. Extending the model from pre-DAA to full DAA is only a matter of refining the trust models on the parties involved. Finally, we present a generic construction of a DAA protocol from new building blocks tailored for anonymous attestation. Some of them are new variations on established ideas and may be of independent interest. We give instantiations for these building blocks that yield a DAA scheme more efficient than the one currently deployed, and as efficient as the one about to be standardized by the TCG which has no valid security proof.     

Ruthenium- and Osmium-Arene Complexes of 2-Substituted Indolo[3,2-c]quinolines: Synthesis, Structure, Spectroscopic Properties, and Antiproliferative Activity

The synthesis of new modified indolo[3,2-c]quinoline ligands L(1)-L(8) with metal-binding sites is reported. By coordination to ruthenium- and osmium-arene moieties 16 complexes of the type [(η(6)-p-cymene)M(L)Cl]Cl (1a,b-8a,b), where M is Ru(II) or Os(II) and L is L(1)-L(8), have been prepared. All compounds were comprehensively characterized by elemental analysis, electrospray ionization mass spectrometry, IR, UV-vis, and NMR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction (2a, 4a, 4b, 5a, 7a, and 7b). The complexes were tested for antiproliferative activity in vitro in three human cancer cell lines, namely, CH1 (ovarian carcinoma), SW480 (colon adenocarcinoma), and A549 (non-small-cell lung cancer), yielding IC(50) values in the submicromolar or low micromolar range.     

Development of organosilicone–polyurethanes as stone preservation and consolidation materials

Two organosilicone-modified polyurethanes are investigated as potential materials for the conservation and consolidation of natural stones. The materials are low molecular weight oligomers at the application stage and react with the humidity of the air to give polymers, forming continuous microlayers. The two differ in the length of the organosilicone chain, resulting in pronounced differences in their physical state: one forms a brittle glassy material (T_g ≈ 70°C). and the other, a soft rubbery material (T_g ≈ −100°C). The rate of the polymerization of the prepolymers was investigated at different conditions, showing a strong dependence on the presence of a catalyst and air humidity. Both these favorable conditions exist probably in the natural stone pores, enhancing the formation of the protective hydrophobic internal microlayer. © 1996 John Wiley & Sons, Inc.     

Solid-Phase Microextraction (SPME) of Pyrazines in Model Reaction Systems

Headspace solid-phase microextraction (HS-SPME) combined with gas chromatography (GC) was used for isolating and analysing pyrazines formed in a model system. This system consisted of an aqueous mixture of glucose, glycine and sodium hydroxide. Pyrazine formation was accelerated by heating in a microwave oven. Results were compared with our earlier ones using conventional techniques for isolation of pyrazines. HS-SPME-GC showed several advantages over traditional methods. The method is rapid, sensitive, easy to use and reproducible. Headspace and liquid of the model reaction were extracted and the results obtained using headspace sampling showed good agreement with the methylene chloride extraction method. In all cases, coefficients of variation of 5% or lower were obtained when the SPME extraction time was consistent.