Guidelines Towards Better Participation of Older Adults in Software Development Processes using a new SPIRAL Method and Participatory Approach

This paper presents a new method of engaging older participants in the process of application and IT solutions development for older adults for emerging IT and tech startups. A new method called SPIRAL (Support for Participant Involvement in Rapid and Agile software development Labs) is proposed which adds both sustainability and flexibility to the development process with older adults. This method is based on the participatory approach and user empowerment of older adults with the aid of a bootstrapped Living Lab concept and it goes beyond well established user-centered and empathic design. SPIRAL provides strategies for direct involvement of older participants in the software development processes from the very early stage to support the agile approach with rapid prototyping, in particular in new and emerging startup environments with limited capabilities, including time, team and resources

Direkter Elektronentransfer und Bioprozessregelung mit Dickschicht-Enzymelektroden

Die Erfassung von direktem Elektronentransfer führt zu Enzymelektroden der dritten Generation, die Aufschaltung eines relativ niedrigen Potentials kann hier Interferenzen minimieren. Die hier verwendeten Dickschicht-Elektroden eignen sich zur Produktion von amperometrischen Sensoren in großen Stückzahlen und können mit Enzymen beschichtet werden. Direkter Elektronentransfer von der Elektrode zur nativen, glykosilierten Peroxidase aus Meerrettich sowie zur rekombinant hergestellten, unglykosilierten Form dieses Enzyms wurde nachgewiesen. Der Vergleich der experimentellen Resultate mit begleitenden Modellrechnungen hinsichtlich der Orientierung der Proteine sowie Elektronentransferraten zeigte, dass bei der hier gewählten Immobilisierungsprozedur beide Peroxidasen direkten Elektronentransfer in vergleichbarem Umfang ermöglichen. Mit ausgewählten Polyelektrolyten als Additiv konnten die erzielten Stromstärken für beide Enzymvarianten deutlich erhöht werden, allerdings ergaben sich für bestimmte Additive unterschiedliche Resultate. Vermutlich handelt es sich um Stabilisierungseffekte, aufgrund der Ergebnisse konnte ein allgemeiner Ansatz zur Wirkungsweise der Additive nicht postuliert werden. Des weiteren wurde automatisiert über mehrere Wochen Bioprozessregelung von tierischen Zellen in Perfusionskultur mit einer Fliessinjektions-Analyse-Apparatur angewandt. Gemessen wurde dabei der Glukosegehalt des Mediums mit Glukoseoxidase-Elektroden.The measurement of direct electron transfer leads to third generarion enzyme electrodes. Interferences can be minimized by the use of relatively low potentials. The used thick-film electrodes are suitable for mass production of amperometric sensors and can be covered with enzymes. Direct electron transfer from the electrode to the native, glycosylated horseradish peroxidase as well as to the recombinant, unglycosylated form of this enzyme has been shown. Comparison of the experimental results with accompanying modelling calculations regarding orientation of the proteins and electron transfer rates showed that due to the used immobilisation procedure both peroxidases enable direct electron transfer in comparable range. Selected polyelectrolytes as additives could increase the resulting currents significantly. However, results differed significantly depending on the additives used. Presumably this results matter from stabilizing effects. Based on these results, a definite explanation regarding the role of the additives could not be postulated. In addition, automated bioprocess control of animal cells was performed in perfusion culture for several weeks with flow injection analysis. In this model the glucose level of the medium was measured with glucose oxidase - electrodes

Plasmon damping below the Landau regime: the role of defects in epitaxial graphene

The sheet plasmon in epitaxially grown graphene layers on SiC(0001) and the influence of surface roughness have been investigated in detail by means of low-energy electron diffraction (LEED) and electron energy loss spectroscopy (EELS). We show that the existence of steps or grain boundaries in this epitaxial system is a source of strong damping, while the dispersion is rather insensitive to defects. To the first order, the lifetime of the plasmons was found to be proportional to the average terrace length and to the plasmon wavelength. A possible reason for this surprisingly efficient plasmon damping may be the close coincidence of phase (and group) velocities of the plasmons ( almost linear dispersion) with the Fermi velocity of the electrons. Therefore, uncorrelated defects like steps only have to act as a momentum source to effectively couple plasmons to the electron-hole continuum

Characterization and first results from LACIS-T : a moist-air wind tunnel to study aerosol–cloud–turbulence interactions

The interactions between turbulence and cloud microphysical processes have been investigated primarily through numerical simulation and field measurements over the last 10 years. However, only in the laboratory we can be confident in our knowledge of initial and boundary conditions and are able to measure under statistically stationary and repeatable conditions. In the scope of this paper, we present a unique turbulent moist-air wind tunnel, called the Turbulent Leipzig Aerosol Cloud Interaction Simulator (LACIS-T) which has been developed at TROPOS in order to study cloud physical processes in general and interactions between turbulence and cloud microphysical processes in particular. The investigations take place under well-defined and reproducible turbulent and thermodynamic conditions covering the temperature range of warm, mixed-phase and cold clouds (25∘C>T>−40∘C ). The continuous-flow design of the facility allows for the investigation of processes occurring on small temporal (up to a few seconds) and spatial scales (micrometer to meter scale) and with a Lagrangian perspective. The here-presented experimental studies using LACIS-T are accompanied and complemented by computational fluid dynamics (CFD) simulations which help us to design experiments as well as to interpret experimental results. In this paper, we will present the fundamental operating principle of LACIS-T, the numerical model, and results concerning the thermodynamic and flow conditions prevailing inside the wind tunnel, combining both characterization measurements and numerical simulations. Finally, the first results are depicted from deliquescence and hygroscopic growth as well as droplet activation and growth experiments. We observe clear indications of the effect of turbulence on the investigated microphysical processes

Characterization and first results from LACIS-T: a moist-air wind tunnel to study aerosol-cloud-turbulence interactions

The interactions between turbulence and cloud microphysical processes have been investigated primarily through numerical simulation and field measurements over the last 10 years. However, only in the laboratory we can be confident in our knowledge of initial and boundary conditions and are able to measure under statistically stationary and repeatable conditions. In the scope of this paper, we present a unique turbulent moist-air wind tunnel, called the Turbulent Leipzig Aerosol Cloud Interaction Simulator (LACIS-T) which has been developed at TROPOS in order to study cloud physical processes in general and interactions between turbulence and cloud microphysical processes in particular. The investigations take place under well-defined and reproducible turbulent and thermodynamic conditions covering the temperature range of warm, mixed-phase and cold clouds (25 °C > T > −40 °C). The continuous-flow design of the facility allows for the investigation of processes occurring on small temporal (up to a few seconds) and spatial scales (micrometer to meter scale) and with a Lagrangian perspective. The here-presented experimental studies using LACIS-T are accompanied and complemented by computational fluid dynamics (CFD) simulations which help us to design experiments as well as to interpret experimental results. In this paper, we will present the fundamental operating principle of LACIS-T, the numerical model, and results concerning the thermodynamic and flow conditions prevailing inside the wind tunnel, combining both characterization measurements and numerical simulations. Finally, the first results are depicted from deliquescence and hygroscopic growth as well as droplet activation and growth experiments. We observe clear indications of the effect of turbulence on the investigated microphysical processes

Comeback of epitaxial graphene for electronics: large-area growth of bilayer-free graphene on SiC

We present a new fabrication method for epitaxial graphene on SiC which enables the growth of ultra-smooth defect- and bilayer-free graphene sheets with an unprecedented reproducibility, a necessary prerequisite for wafer-scale fabrication of high quality graphene-based electronic devices. The inherent but unfavorable formation of high SiC surface terrace steps during high temperature sublimation growth is suppressed by rapid formation of the graphene buffer layer which stabilizes the SiC surface. The enhanced nucleation is enforced by decomposition of polymer adsorbates which act as a carbon source. With most of the steps well below 0.75 nm pure monolayer graphene without bilayer inclusions is formed with lateral dimensions only limited by the size of the substrate. This makes the polymer assisted sublimation growth technique the most promising method for commercial wafer scale epitaxial graphene fabrication. The extraordinary electronic quality is evidenced by quantum resistance metrology at 4.2 K with until now unreached precision and high electron mobilities on mm scale devices.Comment: 20 pages, 6 Figure

Different assembly processes drive shifts in species and functional composition in experimental grasslands varying in sown diversity and community history

Background: The prevalence of different biotic processes (limiting similarity, weaker competitor exclusion) and historical contingency due to priority effects are in the focus of ongoing discussions about community assembly and non-random functional trait distributions. Methodology/Principal Findings: We experimentally manipulated assembly history in a grassland biodiversity experiment (Jena Experiment) by applying two factorially crossed split-plot treatments to all communities: (i) duration of weeding (never weeded since sowing or cessation of weeding after 3 or 6 years); (ii) seed addition (control vs. seed addition 4 years after sowing). Spontaneous colonization of new species in the control treatment without seed addition increased realized species richness and functional richness (FRic), indicating continuously denser packing of niches. Seed addition resulted in forced colonization and increased realized species richness, FRic, functional evenness (FEve) and functional divergence (FDiv), i.e. higher abundances of species with extreme trait values. Furthermore, the colonization of new species led to a decline in FEve through time, suggesting that weaker competitors were reduced in abundance or excluded. Communities with higher initial species richness or with longer time since cessation of weeding were more restricted in the entry of new species and showed smaller increases in FRic after seed addition than other communities. The two assembly-history treatments caused a divergence of species compositions within communities originally established with the same species. Communities originally established with different species converged in species richness and functional trait composition over time, but remained more distinct in species composition. Conclusions/Significance: Contrasting biotic processes (limiting similarity, weaker competitor exclusion) increase functional convergence between communities initially established with different species. Historical contingency with regard to realized species compositions could not be eradicated by cessation of weeding or forced colonization and was still detectable 5 years after application of these treatments, providing evidence for the role of priority effects in community assembly