Improved Management of the Existing Stock - The Case of Poland

This paper traces the changes which have occurred in housing provision and management in Poland during the period of transition to the market system. It suggests that the changes that have occurred have been greatly influenced by the environment within which the reforms have taken place. It claims that changes in housing management are restricted by historic attitudes yet have proceeded due to financial constraints imposed as part of the government's policy for restructuring the economy in the early 1990s. At the same time these restrictions have worked against the developmentof the housing market and investment in the existing housing stock. While the planned programmaticand legislative tasks in the reform of Polish housing are concluded, there is still a need for major shifts in the attitudes of consumers and providers to effect these changes.     

Rheology of starch dispersions at high temperatures

In the food industry, many food products experience extreme processing conditions of high temperature and high shear stresses. The measurements of sample behavior for water-based formulations above 100°C is extremely challenging due to changes in material composition from the boiling of volatile ingredients. We have developed a high-sensitivity, pressurized starch pasting cell (up to 5 bar) which utilizes a design free of mechanical bearings and seals, resulting in an order-of-magnitude improvement in torque sensitivity (1 μN.m in oscillatory and 10 μN.m in shear flows) compared to traditional pressure cells. A pressurized atmosphere in the cell suppresses boiling of the volatile components, allowing the characterization of the structure–property relationships of the sample over a range of testing conditions (−5 to 150°C) which simulate industrial processing and storage conditions. This cell is employed to investigate the pasting properties of a commercial starch dispersed in water. In situ gelatinization of starch dispersions of varying starch particle weight fractions (ϕ) subjected to a high temperature (120°C) at elevated pressure and at a fixed shear rate is studied. A phase transition, from an initial flowable starch slurry to a paste, takes place during which the viscosity evolves by several orders of magnitude. Typical parameters associated with the viscosity evolution during gelatinization such as onset temperature, peak temperature, and peak viscosity are analyzed to probe the impact of high temperature on the gelation process and the rheological properties of the final starch paste. Furthermore, yield stresses of the final paste, measured at 120°C, are examined for varying ϕ through traditional rheological methods such as flow ramps, oscillatory shear, and stress growth, demonstrating the capabilities of this cell for studies of steady shear and nonlinear viscoelastic behavior of the starch pastes. The yield stress values are found to be in good agreement when comparing various testing methods. Yield stresses range from 0.25 to 6.5 Pa for ϕ between 0.05 and 0.15, with 0.05 being the minimum starch weight fraction for which there is any measurable yield stress. The yield stress and the paste viscosity both scale with starch particle weight fraction as (ϕ − ϕ_c) ^m, where ϕ_c = 0.04 as no yield stress is observed for ϕ ≤ 0.04. The exponent, m, for yield stress is found to be in the range of 1.15–1.4 depending on the analytical method used and the definition of yield stress while for peak and breakdown viscosities it is noted to be 1.6 and 1.1, respectively. The Herschel-Bulkley model is found to fit the flow curves well. The starch pastes are found to exhibit shear-thinning and significant thixotropic behavior.     

Stem Cell Therapy Enhances Motor Activity of Triceps Surae Muscle in Mice with Hereditary Peripheral Neuropathy

Impaired motor and sensory functions are the main features of Charcot–Marie–Tooth disease. Mesenchymal stem cell (MSCs) therapy is one of the possible treatments for this disease. It was assumed that MSCs therapy can improve the contractile properties of the triceps surae (TS) muscles in mice with hereditary peripheral neuropathy. Murine adipose-derived mesenchymal stromal cells (AD-MSCs) were obtained for transplantation into TS muscles of FVB-C-Tg(GFPU)5Nagy/J mice. Three months after AD-MSCs transplantation, animals were subjected to electrophysiological investigations. Parameters of TS muscle tension after intermittent high frequency electrical sciatic nerve stimulations were analyzed. It was found that force of TS muscle tension contraction in animals after AD-MSCs treatment was two-time higher than in untreated mice. Normalized values of force muscle contraction in different phases of electrical stimulation were 0.3 ± 0.01 vs. 0.18 ± 0.01 and 0.26 ± 0.03 vs. 0.13 ± 0.03 for treated and untreated animals, respectively. It is assumed that the two-fold increase in TS muscle strength was caused by stem cell therapy. Apparently, AD-MSCs therapy can promote nerve regeneration and partial restoration of muscle function, and thus can be a potential therapeutic agent for the treatment of peripheral neuropathies.     

An investigation into the surface fatigue of materials and thin layers using a sliding diamond spherical segment

Methods for testing the surface fatigue of materials or thin layers normally involve configurations with two or more rolling balls or discs. Such equipment and test specimens are quite complicated, and for a large number of experiments, costly. Testing could be considerably simplified if the stressing of the material surface were performed with a sliding natural diamond spherical segment. A diamond on steel (or any different material) friction pair has the particular attribute that sliding wear is absent. Under these circumstances, after a certain number of strain cycles, fatigue failure of the investigated surface or layers appears. A particularly relevant application is investigation of the adhesion of a DLC layer.     

Activation of Drosophila melanogaster TRPA1 Isoforms by Citronellal and Menthol

Background: The transient receptor potential ankyrin 1 (TRPA1) cation channels function as broadly-tuned sensors of noxious chemicals in many species. Recent studies identified four functional TRPA1 isoforms in Drosophila melanogaster (dTRPA1(A) to (D)), but their responses to non-electrophilic chemicals are yet to be fully characterized. Methods: We determined the behavioral responses of adult flies to the mammalian TRPA1 non-electrophilic activators citronellal and menthol, and characterized the effects of these compounds on all four dTRPA1 channel isoforms using intracellular Ca²⁺ imaging and whole-cell patch-clamp recordings. Results: Wild type flies avoided citronellal and menthol in an olfactory test and this behavior was reduced in dTrpA1 mutant flies. Both compounds activate all dTRPA1 isoforms in the heterologous expression system HEK293T, with the following sensitivity series: dTRPA1(C) = dTRPA1(D) > dTRPA1(A) ≫ dTRPA1(B) for citronellal and dTRPA1(A) > dTRPA1(D) > dTRPA1(C) > dTRPA1(B) for menthol. Conclusions: dTrpA1 was required for the normal avoidance of Drosophila melanogaster towards citronellal and menthol. All dTRPA1 isoforms are activated by both compounds, but the dTRPA1(B) is consistently the least sensitive. We discuss how these findings may guide further studies on the physiological roles and the structural bases of chemical sensitivity of TRPA1 channels.     

Investigating the effects of reduced size on the properties of ferroelectrics

A series of experiments has been undertaken to understand more about the fundamental origin of the thickness-induced permittivity collapse often observed in conventional thin film ferroelectric heterostructures. The various experiments are discussed, highlighting the eventual need to examine permittivity collapse in thin film single crystal material. It has been seen that dielectric collapse is not a direct consequence of reduced size, and neither is it a consequence of unavoidable physics associated with the ferroelectric-electrode boundary. Research on three-dimensional shape-constrained ferroelectrics, emphasizing self-assembled structures based on nanoporous alumina templates and on FIB-milled single crystals, is also presented, and appears to represent an exciting area for ongoing research.     

Rarefied gas dynamics aspects of pharmaceutical freeze-drying

Freeze-drying is a low-pressure, low-temperature condensation pumping process widely used in manufacture of bio/pharmaceutical products. Because of the need to avoid the aggressive evaporation drying, typical operating pressures in freeze-drying are below 100 Pa. Understanding relevant rarefied flow physics can help improve freeze-drying systems and processes. The paper presents various rarefied gas dynamics aspects of freeze-drying including thermal creep and conduction, pressure and concentration-gradient driven flows and sonic expansion flows with icing. In particular, flow through the duct where the Knudsen number is small enough is modeled using conventional CFD techniques. The effect of the hardware on flow in the duct is discussed in detail. Furthermore, flow and icing in the freeze-drying condenser is modeled using the direct simulation Monte Carlo (DSMC) technique. The effect of duct length on the uniformity of mass flux and ice accretion rates are discussed. It is found that by increasing the duct length, there is a trade-off between increased residual pressure and improved uniformity. The simulations show that by augmenting the DSMC method with conventional CFD technique in appropriate regimes, the gas dynamics in the entire freeze-dryer system can be modeled numerically for given sublimation rate and geometry.     

On-line laser-induced breakdown spectroscopy determination of magnesium coating thickness on electrolytically galvanized steel in motion

The application of laser-induced breakdown spectroscopy (LIBS) for online analysis of novel Zn based alloy coatings during continuous production of galvannealed steel has been demonstrated. Field trials were carried out at the ThyssenKrupp Steel (TKS) pilot plant in Dortmund, Germany. For this purpose, a portable LIBS demonstrator was constructed and evaluated, based on a dual-pulse Q-switched Nd:YAG laser, operated at 1064 nm. This system was used to generate plasmas on the moving sample surface after the annealing process, in order to control on-line the thickness of Mg on electrolytically galvanized steel. For variable Mg thicknesses (depending on strip speed of the pilot line, 100-1200 nm), and for steel sheets with a predetermined and constant Zn thickness (of 2 or 9 μm), a satisfactory agreement between plant LIBS measurements and data from laboratory chemical analysis (dissolution of the metallic coating and subsequent inductively coupled plasma-optical emission spectroscopy (ICP-OES) analysis) of Mg coating thicknesses has been obtained. The effects of environmental conditions on field measurements (strip temperature, mechanical vibrations, moisture on surface, etc.) have been demonstrated to be negligible, whereas minimal damage (crater diameters less than 150 μm) to the sample surface was caused.