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Biochips, of the microarray type, are fast becoming the default tool for combinatorial chemical and biological analysis in environmental and medical studies. Programmable biochips are miniaturized biochemical labs that are physically and/or electronically controllable. The technology combines digital photolithography, microfluidics and chemistry. The precise positioning of the samples (e.g., DNA solutes or proteins) on the surface of the chip in pico liter to nano liter volumes can be done either by means of external forces (active devices) or by specific geometric patterns (passive devices). The active devices which will be considered here are nano liter fluidic biochips where the core of the technology are nano pumps featuring surface acoustic waves generated by electric pulses of high frequency. These waves propagate like a miniaturized earthquake, enter the fluid filled channels on top of the chip and cause an acoustic streaming in the fluid which provides the transport of the samples. The mathematical model represents a multiphysics problem consisting of the piezoelectric equations coupled with multiscale compressible Navier-Stokes equations that have to be treated by an appropriate homogenization approach. We discuss the modeling approach and present algorithmic tools for numerical simulations as well as visualizations of simulation results. [ABSTRACT FROM AUTHOR]

The telecommunication market and, with it, telecommunication product design has undergone drastic changes in the past years. As a consequence, modeling and simulation are confronted with new challenges. In this paper we outline some requirement changes for simulation design. We believe that the focus must be on rapidity, robustness, simplicity and intuitiveness and are willing to sacrifice exactness to some extent. We base our statements on the assumption that modeling and simulation ultimately serve to facilitate decision making and that the most important decisions are made in the early design phase. We also stress that managers, who take decisions, prefer robust decisions to optimal decisions for singular cases. That is, they prefer decisions that are valid for a number of imaginable scenarios. Starting from the requirement of rapidity, robustness, simplicity and intuitiveness we suggest a strategy to tackle modeling and simulation: HALDA - heterogeneous abstraction level design approach, where we develop ideas from system test and system integration test and carry them over to the early design phase. [ABSTRACT FROM AUTHOR]

In Germany about 11 million t/a of municipal solid waste is incinerated giving 3 million t/a of ashes (slags). The assessment of the ashes and their possible usage get increasing attention worldwide. Several leaching tests have been developed. However, most of them consider the total concentrations of soluble species only. [ABSTRACT FROM AUTHOR]

Automotive system design demands frequent exchange of data between different parties and tools. In order to improve the interoperability, standardization bodies and partnerships have put high effort in defining XML based languages for system descriptions. However, the mere existence of a standardized XML based data exchange format doesn't guarantee seamless interoperability. The validation possibilities given by XML DTD or Schema are not sufficient. Additionally, the maintenance of XML formats for the growing complexity of today's systems is an increasing challenge. This paper describes the experiences with the model-driven approach taken by the automotive initiative AUTOSAR. It illustrates the limitations of designing data exchange formats in XML and shows how a higher level of abstraction increases the interoperability between tools. A powerful concept for mapping a metamodel to XML schema allows for integrating legacy XML formats. Furthermore, current activities on improving interoperability by automatically generating a tool framework for AUTOSAR and other automotive tools are explained. [ABSTRACT FROM AUTHOR]

1202 patients suffering from Parkinson's disease switched from other dopamine agonists to pramipexole under open conditions either abruptly or in an overlapping, gradual manner. Mostly insufficient effectiveness motivated the switch. The investigators gave equal preference to either an abrupt or an overlapping switch to pramipexole in this observational study. There was a tendency in favour of the overlapping switch procedure in those patients who were on a relatively higher dose of a dopamine agonist before the switch. The switch was performed because the investigators expected the effect of pramipexole on tremor, motor functions and depression/anhedonia to be better compared with previous dopamine agonists. The main reasons for switching to pramipexole (anti-tremor effect, anti-depressive/anti-anhedonic effect) as given by the physicians at baseline came up to expectations. The switch to pramipexole mostly yielded further improvements irrespective of the mode of switching. [ABSTRACT FROM AUTHOR]

Industry research tends to be product oriented. Simulations are expected to mimic the behavior of a specific product, a product that is often in the design phase. The product's features, in turn, depend on ever changing market forecasts. At the same time, reliability is a must, since business decisions are based on simulation results. We look at the example of tool design for UMTS system level simulations to highlight the challenges of simulation tool development in the telecommunication industry and to discuss solution strategies. [ABSTRACT FROM AUTHOR]

We have demonstrated for the first time that element-selective laser ionization in combination with ultra-high resolution mass spectrometry can be used to prepare isomerically pure ion ensembles. Together with β-γ coincidence studies this method allowed a determination of the low-energy structure and the unambiguous identification of triple β-decaying isomerism in 70Cu. By selective resonant ionization and measurement of the masses of these three states using ISOLTRAP at ISOLDE/CERN with a relative uncertainty of δm/m ≈ 5 · 10−8 a clear state-to-mass assignment was possible which resolved the assignment puzzle in 70Cu. [ABSTRACT FROM AUTHOR]

The resonance ionization laser ion source (RILIS) of the ISOLDE on-line isotope separation facility is based on the method of laser step-wise resonance ionization of atoms in a hot metal cavity. The atomic selectivity of the RILIS complements the mass selection process of the ISOLDE separator magnets to provide beams of a chosen isotope with greatly reduced isobaric contamination. Using a system of dye lasers pumped by copper vapour lasers, ion beams of 24 elements have been generated at ISOLDE with ionization efficiencies in the range of 0.5-15%. As part of the ongoing RILIS development off-line resonance ionization spectroscopy studies carried out in 2003 and 2004 have determined the optimal three-step ionization schemes for scandium, antimony, dysprosium and yttrium. [ABSTRACT FROM AUTHOR]

The ongoing progress in establishing a reference sequence as part of the Human Genome Project (1) has revealed a new challenge: the large-scale identification and detection of intraspecies sequence variations, either between individuals or populations. The information drawn from those studies will lead to a detailed understanding of genetic and environmental contributions to the etiology of complex diseases. [ABSTRACT FROM AUTHOR]

The ongoing progress in establishing a reference sequence as part of the Human Genome Project (1) has revealed a new challenge: the large-scale identification and detection of intraspecies sequence variations, either between individuals or populations. The information drawn from those studies will lead to a detailed understanding of genetic and environmental contributions to the etiology of complex diseases. [ABSTRACT FROM AUTHOR]

ISOL beams of 19−22O were produced at ISOLDE and GANIL. At ISOLDE the neutron-rich oxygen isotopes are produced by 1.4 GeV proton-induced reactions in a UCx/graphite target. The target is connected via a water-cooled transfer line (to retain all non-volatile isobars) to an ISOLDE type FEBIAD ion source where the released CO is dominantly ionized as CO+. 19−22O beams were also produced at SPIRAL (GANIL). A 77.5 MeV/nucleon 36S beam was fragmented in a thick graphite target, coupled by a cold transfer tube to an ECR ion source which ionizes the released CO dominantly as O+ and CO+. [ABSTRACT FROM AUTHOR]