Transitory urbanites: New actors of residential change in Polish and Czech inner cities

For decades inner cities in East Central Europe have been characterised by physical dilapidation, ageing in place and selective outmigration. Post-socialist transition added to these developments by further outmigration due to suburbanisation but also provided new opportunities of residential change. In Polish and Czech second-order cities there is selective in-migration by younger households which remains so far almost hidden to the official statistics. Among them a new type of inner-city dwellers can be identified, that is transitory urbanites. They take the inner city as a perfect residential place in their current phase of life and value its characteristics both in emotional and pragmatic terms. But they do not expect to stay there for good and might leave the inner city in the future for another urban area or suburbia. However, while being present now they bring about residential change in the inner city and pave the way for future in-migrants of similar social status and age. From our material and observations, we can formulate the hypothesis that their importance has increased decisively during the last decade. Our paper draws on empirical research from in ?ód? and Brno from 2006 to 2009.     

Hydrogen and Zr-based metallic glasses: Gas/solid absorption process and structure evolution

The absorption of hydrogen by means of gas-solid reaction and its consequence on the structure have been studied for fully amorphous alloys as well as quasicrystals/glassy composite alloys based on the composition Zr₅₉Ti₃Cu₂₀Al₁₀Ni₈. The process of hydrogen absorption has been performed and monitored under 20 bar of H₂ using high pressure-differential scanning calorimetry (HP-DSC). The structure evolution of the samples has been followed by X-ray diffractometry (XRD). Results show that the nature of the surface oxide layer strongly affects the process of hydrogen absorption, especially its starting temperature. The structure evolves nevertheless along the same basic sequence, regardless of the sample: (i) the alloys keep a global amorphous structure up to roughly H/M = 0.8 and T = 350 °C; (ii) then ZrH₂ and at higher temperature Cu₂AlZr are formed. The stability of the glass is weakened and the formation of quasicrystals is inhibited under 20 bar of H₂. An heterogeneous distribution of hydrogen atoms inside the amorphous matrix has been inferred from the results.     

Contribution on the influence of transformation structures under consideration of austenite deformation

Hot forming represents a substantial part of the manufacturing process of many steel products. The crucial microstructural transformation process, which influences the characteristics of a steel considerably, is undisputed the γ/α‐transformation. A successful aid to the interpretation of possible microstructural transformation processes during cooling from the austenitizing or deformation temperature is the determination and handling of CCT diagrams. In this article two steels are examined which differ only in their titanium content. Dilatometric investigations were performed varying the three parameters' transformation temperature, strain and cooling strategy. The insights gathered are illustrated and discussed with the aid of CCT diagrams. An additional transformation below A_c1 with a brief curing reheat up to A_c3 + 20 K leads to a substantially finer structure. The exploitation of this effect may be of great industrial importance.     

Monitoring freeze/thaw cycles using ENVISAT ASAR Global Mode

Due to the high temporal sampling rate of ASAR Global Monitoring (GM) mode, it has a high application potential for analyzing the land surface freeze/thaw process in high latitudes. This study aims to develop effective methods of extracting freeze/thaw transition dates of permafrost areas from ASAR GM data sets. In order to use ASAR GM time-series for analyzing freeze/thaw states, a least square fitting of piecewise step function is introduced. The thawing date can be determined by minimizing the sum of squared residuals between measured backscattering time-series and a pre-defined step function. An experimental result for a Siberian permafrost region illustrates that it can be a promising approach in monitoring permafrost ecosystems.     

Synthesis and physical characterization of magnetite nanoparticles for biomedical applications

Iron oxide nanoparticles for biomedical applications in the size range of 15–130 nm were prepared by either oxidative hydrolysis of ferrous sulfate with KOH or precipitation from ferrous/ferric chloride solutions. The magnetite particle size is controlled by variation of pH and temperature. The synthesized magnetite nanoparticles are partially oxidized as signaled by ferrous concentrations of below 24 wt% Fe²⁺ and lattice parameters of a₀ ≤ 8.39 Å which are smaller compared to 8.39 Å for stoichiometric magnetite. The extend of oxidation increases with decreasing particle size. Heating at 150–350 °C topotactically transforms the magnetite nanoparticles into stoichiometric tetragonal maghemite (ferrous ion concentration c_Fe²⁺=0 and a₀ = 8.34 Å) without significant particle growth. The magnetite–maghemite transformation is studied with thermal analysis, XRD and IR spectroscopy. The saturation magnetizations of the magnetite and maghemite particles decrease with decreasing particle size. The variation of M_s with particle size is interpreted using a magnetic core–shell particle model. Magnetite particles with d ≤ 16 nm show superparamagnetic behavior at room temperature whereas particles with diameter >16 nm display hysteresis behavior. These particles are candidates for biomedical applications, e.g. controlled drug release or hyperthermia.     

Electrocrystallisation of metallic films under the influence of an external homogeneous magnetic field—Early stages of the layer growth

The effects of a uniform magnetic field on the early stages of Ag, Fe and CoFe alloys electrocrystallisation have been investigated. It was found for Fe and CoFe alloys, irrespective of the applied parameters, that early stages of the layer growth can be characterised by a nucleation and 3D diffusion controlled growth. The influence of the deposition parameters on the nucleation behaviour was studied on the basis of the Sharifker-Mostany (SM) model. A modification to the existing model has been proposed in order to model alloy systems. It is reported that a magnetic field superposed parallel to the electrode surface has a significant influence on the early stages of Fe and CoFe alloys growth. The growth of the nuclei is enhanced by the Lorentz-force-driven convection, while the nucleation processes remain unaffected. The hydrodynamic origin of these phenomena is confirmed by independent rotating disk electrode (RDE) investigations. Moreover, the proposed mechanism of a magnetic field influence on the 3D diffusion controlled growth is supported by a microscopic investigation of Ag deposits. It was found that Ag deposits obtained without a magnetic field superposition are characterised by a relatively large number of small 3D growth centres, whereas the deposits obtained in a field show fewer 3D centres but their size is greatly increased.     

Children's Sex-Stereotyped Self-Socialization Through Selective Exposure to Entertainment: Cross-Cultural Experiments in Germany, China, and the United States

Chinese, German, and U.S. American 4- to 6-year-old boys and girls were asked to select videos of children stories that they would most like to see. Choices were either between pairs of story videos presenting aggressive versus peaceful, nurturing content, with male or female sex of story protagonists held constant, or between pairs of videos featuring male versus female protagonists, with aggressive or peaceful story content held constant. Across countries/cultures, boys showed a strong preference for aggressive stories; girls for peaceful, nurturing ones. Again across countries/cultures, both sexes favored stories featuring protagonists of their own sex. However, the preference for same-sex story protagonists was particularly strong in American and Chinese girls. In comparison, American and Chinese boys showed only a moderate preference for male characters.