Location-based services deployment and demand: a roadmap model

The advancements in mobile, wireless and positioning technologies have enabled applications and services such as route guiding and emergency call-out assistance. These and other similar services have become known as ‘location-based services’ (LBS). The literature on LBS development and deployment addresses technological issues (for example, usability and integration) and issues related to LBS implementation—including LBS business models, adoption and customer concerns and requirements. In the study presented here LBS development and deployment were investigated from a case study perspective and the LBS landscape is explored and analyzed. The study finds that while the regulatory environment has played a critical role as a success factor in the markets investigated some of innovative business approaches may have been equally important as customer demand generators. Economies on the road to deploying LBS should therefore focus on creating a supportive environment encouraging the development of services, which meet the identified needs and requirements of the target customer market.     

Water Sorption by Carbon Fibers

Protection of Metals and Physical Chemistry of Surfaces - The degree of crystallinity of carbon fibers (CFs) of different manufacturers has been determined by means of the Raman scattering method....     

A Microfluidic 3D Endothelium-on-a-Chip Model to Study Transendothelial Migration of T Cells in Health and Disease

The recruitment of T cells is a crucial component in the inflammatory cascade of the body. The process involves the transport of T cells through the vascular system and their stable arrest to vessel walls at the site of inflammation, followed by extravasation and subsequent infiltration into tissue. Here, we describe an assay to study 3D T cell dynamics under flow in real time using a high-throughput, artificial membrane-free microfluidic platform that allows unimpeded extravasation of T cells. We show that primary human T cells adhere to endothelial vessel walls upon perfusion of microvessels and can be stimulated to undergo transendothelial migration (TEM) by TNFα-mediated vascular inflammation and the presence of CXCL12 gradients or ECM-embedded melanoma cells. Notably, migratory behavior was found to differ depending on T cell activation states. The assay is unique in its comprehensiveness for modelling T cell trafficking, arrest, extravasation and migration, all in one system, combined with its throughput, quality of imaging and ease of use. We envision routine use of this assay to study immunological processes and expect it to spur research in the fields of immunological disorders, immuno-oncology and the development of novel immunotherapeutics.     

Mechanochemical solid-phase reactions of humic acids with metal ions

The mechanochemical solid-phase reactions of humic acid with Cu²⁺, Ni²⁺, and Cd²⁺ metal ions were studied. The analysis of the mineral composition of humic acids by atomic emission spectrometry showed an increase in the concentrations of Cu²⁺, Ni²⁺, and Cd²⁺ ions after mechanical treatment.     

Medical hydrogels based on bioactive compounds. Synthesis,properties, and possible application for preparing bactericidal materials

Several physicochemical analytical methods were used to study aqueous solutions and hydrogels based on L-cysteine and silver nitrate. It was found that anions played a decisive role in forming the threedimensional gel-network in dilute silver-cysteine solutions. The ability to use silver-cysteine solutions and hydrogels to prepare bactericidal fibers and fabrics was examined.     

Mechanism of anodic oxidation of molybdenum in nearly-neutral electrolytes studied by electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy

Anodic oxidation of molybdenum in weakly acidic, nearly neutral and weakly alkaline electrolytes was studied by voltammetric and electrochemical impedance spectroscopic measurements in a wide potential and pH range. Current vs. potential curves were found to exhibit two pseudo-Tafel regions suggesting two parallel pathways of the dissolution process. Electrochemical impedance spectra indicated the presence of at least two reaction intermediates. X-ray photoelectron spectroscopic (XPS) results pointed to the formation of an oxide containing Mo(IV), Mo(V) and Mo(VI), the exact ratio between different valence states depending on potential and pH of the solution. A physico-chemical model of the processes is proposed and a set of kinetic equations for the steady-state current vs. potential curve and the impedance response are derived. The model is found to reproduce quantitatively the current vs. potential curves and impedance spectra at a range of potentials and pH and to agree qualitatively with the XPS results. Subject to further improvement, the model could serve as a starting point for the optimization of the electrochemical fabrication of functional molybdenum oxide coatings.     

Heats (enthalpies) of formation of coals and the thermodynamic evaluation of the coal formation process

An approach to the calculation of the quantity of heat consumed in the process of coal formation is presented. The variability of this parameter in a coalification series is analyzed using coals from the Kuznetsk and Tunguska Basins as an example.     

Formation of medium-range order in fluoride glasses

A possible solution to the problem of determining the medium-range order in fluoride glasses is proposed. The model of the formation of the glass network is advanced on the basis of the complex-cluster model for salt melts and the percolation hypothesis. The determination of the glass network topology reduces to the experimental determination of the percolation point and the geometric estimation of the second coordination number of a glass-former. It is shown that the functionalities of glass-formers as determined from both the percolation point and the crystal chemical constraints turn out to be identical.     

Properties of composites containing biologically active substances and the polymeric materials prepared from them

The effect of the structure of polysaccharides containing ionogenic groups on the properties of proteolytic enzymes included in the structure of polyelectrolyte complexes was investigated. A correlation was established between the composition of the polymer composites containing the proteolytic enzyme, the antimicrobial, and the modifying additives and the properties of the fibre and film materials prepared from them. Moscow State Textile Academy. Translated fromKhimicheskie Volokna, No. 4, pp. 32–38, July–August, 1999.