LIVING ON THE EDGE?

Housing estates, satellite cities and other formerly idealistic social housing projects are subject to certain modes of representation that often affirm the notion of centre and periphery. The analysis of two series by German photographer Tobias Zielony shot on the outskirts of Marseille, France (Quartiers Nord, 2003) and Halle, Germany (Ha Neu, 2003) shows that these representations may be challenged. By adopting a particularly individual perspective, Zielony underlines photography’s ability to inspire change in our perception of what might be marginal.     

Formation of silicon nanocrystals in SiN<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript> film on PET substrates using femtosecond laser pulses

The formation of Si nanoclusters under the action of femtosecond laser pulses in a SiN _x film containing excess silicon has been studied. The initial film was grown by plasmachemical deposition at 100°C on a PET substrate. The pulsed crystallization was effected by a Ti-sapphire laser operating at a wavelength of 800 nm and a pulse duration of about 50 fs. According to the Raman spectroscopy data, the pulsed laser annealing stimulated the accumulation of excess silicon in nanoclusters and their crystallization. The proposed approach can be used for the formation of semiconductor nanocrystals in dielectric films on various plastic (polymer) substrates.     

Parabolic Flights @ Home

We developed an unmanned air vehicle (UAV) suitable for small parabolic-flight experiments. The flight speed of 100 m s^− 1 is sufficient for zero-gravity parabolas of 16 s duration. The flight path’s length of slightly more than 1 km and 400 m difference in altitude is suitable for ground controlled or supervised flights. Since this fits within the limits set for model aircraft, no additional clearance is required for operation. Our UAV provides a cost-effective platform readily available for low-g experiments, which can be performed locally without major preparation. A payload with a size of up to 0.9 ×0.3 ×0.3 m³ and a mass of ∼5 kg can be exposed to 0 g ₀–5 g ₀, with g ₀ being the gravitational acceleration of the Earth. Flight-duration depends on the desired acceleration level, e.g. 17 s at 0.17 g ₀ (lunar surface level) or 21 s at 0.38 g ₀ (Martian surface level). The aircraft has a mass of 25 kg (including payload) and a wingspan of 2 m. It is powered by a jet engine with an exhaust speed of 450 m s^− 1 providing a thrust of 180 N. The parabolic-flight curves are automated by exploiting the advantages of sophisticated micro-electronics to minimize acceleration errors.     

Physiochemical characterization of five iron tubercles from a single drinking water distribution system: Possible new insights on their formation and growth

Physiochemical data were obtained for five iron tubercles from a single drinking water distribution system (DS). Texturally, there were two groups based on internal morphology: one with a core of soft brownish material marbled with veins of a hard black material, the other has a core consisting mostly of the hard, black material. Three iron mineral phases occur, α-FeOOH, γ-FeOOH, or Fe₃O₄. All three coexist in each tubercle but in widely varying proportions. These iron pipe tubercles exhibit a greater diversity within a single DS than previously thought. Because the chemical conditions for the formation of each material is different, water quality parameters may not be the main control of tubercle formation and growth.     

Thermal and electromagnetic parameters of a high-frequency discharge in induction heating of a gas

A procedure for determining the thermal and electrophysical parameters of an hf induction discharge burning inside a short induction heater is proposed.Kazan Technological University. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 68, No. 2, pp. 248–252, March–April, 1995.     

Role of the C-terminal extension in the interaction of S100A1 with GFAP, tubulin, the S100A1- and S100B-inhibitory peptide, TRTK-12, and a peptide derived from p53, and the S100A1 inhibitory effect on GFAP polymerization

Controversy over the efficacy of many topical wound treatments, particularly growth factors, is common, with many clinical practitioners still confused as to the real value of these agents. A serious lack of knowledge appears to exist concerning the diffusion and distribution of topically applied solutes in wounds. Without this basic understanding there seems little chance of accurately predicting the therapeutic window of drugs targeted at cellular activities, such as division and chemotaxis, and processes, such as collagen lattice deposition and contraction, occurring below the surface of the granulating layer. This study was designed to determine the absorption and distribution of a number of radiolabeled solutes (water, sodium chloride, lidocaine) and growth factors (basic fibroblast growth factor, epidermal growth factor) applied topically to full-thickness excisional wounds in rats during the early (2 d), mid (7 d), and late (12 d) stages of repair. Results showed that water and sodium penetrated deepest into wound sites and that changes in water distribution and retention in the wound paralleled the healing process. Multiple stepwise regression showed that molecular weight and tissue depth, but not day of healing, were significant factors in predicting the concentration of each solute in wound and underlying tissue sites. This finding was consistent with a tissue diffusion model developed in this study. Basic fibroblast growth factor and epidermal growth factor only penetrated slightly into the upper granulating layers of the wound site, and calculation of therapeutic doses, based on the percentage of applied solute reaching the deeper granulating layers, is presented.     

Partially reversible adsorption of annexin A1 on POPC/POPS bilayers investigated by QCM measurements, SFM, and DMC simulations

The kinetics of annexin A1 binding to solid-supported lipid bilayers consisting of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoserine (POPS; 4:1) has been investigated as a function of the calcium ion concentration in the bulk phase. Quartz crystal microbalance measurements in conjunction with scanning force microscopy, fluorescence microscopy, and computer simulations indicate that at a given Ca2+ concentration annexin A1 adsorbs irreversibly on membrane domains enriched in POPS. By contrast, annexin A1 adsorbs reversibly on the POPC-enriched phase, which is composed of single POPS molecules embedded within a POPC matrix. The overall area occupied by the POPS-enriched phase is controlled by the CaCl2 concentration. Monte Carlo simulations suggest that the area of the POPS-enriched phase increases by a factor of 7 when the Ca2+ concentration is changed from 0.01 to 1 mM.     

Dezentrale Aufbereitung und Lagerung von Speiseresten – Neue Wege zur Ressourcen- und Energiespeicherung

Organic waste, especially kitchen and canteen waste, is produced in large quantities and is subject to considerable fluctuations, both in terms of its composition and quantity, due in part to changing seasonal factors. Kitchen waste commonly undergoes biological and primarily anaerobic waste treatment (fermentation), producing both material (digestate, fertilizers and soil conditioners) and energy resources (biogas, electrical and thermal energy). The introduction of decentral collection and treatment systems promises to offer new solutions with regard to resource and energy storage, and with regard to compensating for the previously mentioned fluctuations. Within this study kitchen waste was initially pretreated and processed at laboratory scale. Subsequently, the influence of storage at 5, 20 and 30?°C for a period of 28 days was investigated. It was determined that, when stored, acidification and a corresponding drop in pH value promptly set in. The higher the temperature, the higher the level of acidification and the higher the concentration of organic acids became. In order to analyze the effects of storage on kitchen waste as an energy source, its biogas potential was measured in correlation with storage duration and temperature. Neither factor proved to have any significant influence on gas yield. Due to acidification, which can be seen as a chemical decomposition process, stored substrates produced up to 20?% higher gas yield compared to the original substrate. Accordingly, unavoidable kitchen and canteen waste can be considered valuable energy sources, which can contribute to efficient and needs-oriented energy production.