Spectral properties of Eu(III) complexes with heteropolyanions immobilised in xerogel matrices

Eu³⁺ complexes with two heteropolymetalates (HPMs) were entrapped in various xerogel matrices by the sol-gel process. The spectral behaviour of these complexes in the rigid xerogel was studied by means of absorption and emission spectra. The luminescence emission experiments prove that photoexcitation of the HPM lattices (tungstate and molybdate) induced the energy transfer from the oxygen-to-metal charge transfer {O→M (= W, Mo)} triplet states to Eu³⁺ (⁷F_0,1,2→⁵D_0,1). Among the studied matrices with the Eu(III) complexes the best results, i.e. highest relative intensity and longest lifetime, were observed for methylated silicate (SiO₂-polydimethylsiloxane) and silica. In both the cases intensity of the emission could be improved by drying at elevated temperature. The studied materials consisting of complexes Eu³⁺ with the HPMs exhibit in practice stable emission intensity during UV irradiation.     

Do the levels of selected metals differ significantly between the roots of carious and non-carious teeth?

Since the metals deposited in teeth during formation and mineralization processes are to a large extent retained, human teeth receive a considerable attention as the indicators of the heavy metal exposure. The use of permanent teeth is limited because the extraction of healthy permanent teeth just for this purpose is hardly acceptable. As the issue of the loss of elements from a carious lesion in the coronal part of a tooth remains controversial, the valuable material could only be the root of carious and fractured permanent teeth. However, to ensure the validity of the results, it should be ascertained that the levels of certain toxic and essential elements do not differ significantly between the roots of non-carious and carious teeth, and therefore this is the aim of this project. The levels of cadmium, chromium, copper, iron, manganese, lead, zinc, potassium, sodium, calcium and magnesium were determined in the roots of 344 permanent teeth (189 carious and 155 caries-free teeth) from the residents of Ruda Slaska, Poland, aged 18 to 34. No statistically significant difference between the concentration of these metals in the roots of non-carious and carious teeth was found. This finding applies to both the general population and after the grouping by donor's gender and tooth type. The concentration of lead, iron, calcium and manganese in the roots of non-carious and carious teeth exhibited dependence upon tooth type, as well as the concentration of potassium in the roots of carious teeth. Since the mineral composition of the roots of permanent teeth is similar for the non-carious, as well as the carious teeth, they can be indiscriminately selected for the tests required by a research project, as they will produce the comparable results. However, in the case of lead, iron, calcium, potassium and manganese, the comparison should be made after grouping by tooth type.     

Real-Time Fire Monitoring and Visualization for the Post-Ignition Fire State in a Building

During a fire event, environmental threats to building occupants and first responders include extreme temperatures, toxic gases, disorientation due to poor visibility coupled with unfamiliar surroundings, and a changing indoor environment. In addition to these hazards, firefighters often lack critical information for making decisions once on the scene. The lack of information coupled with the dynamics of natural fire events leads to several near-misses, injuries, and deaths each year. Additionally, these challenges slow the rescue time of building occupants and prolong the suppression of the fire. Integrating real-time measurements from sensors into the fire intervention strategy may provide an opportunity for a new technological advancement to improve the practice of firefighting. In this study, a computational framework using Lightweight Communications and Marshalling was developed for connecting real-time fire data to an event detection sub-model to demonstrate how computing can be used for fire monitoring and sensor-assisted firefighting. A post-processed example using these monitoring computations in conjunction with a building information model is provided as a demonstration for presenting real-time data in the field. This work serves as a step towards an intelligent firefighting system based on real-time computing tools.     

Differential Response of Lung Cancer Cells,with Various Driver Mutations,to Plant Polyphenol Resveratrol and Vitamin D Active Metabolite PRI-2191

Plant polyphenols and vitamins D exhibit chemopreventive and therapeutic anticancer effects. We first evaluated the biological effects of the plant polyphenol resveratrol (RESV) and vitamin D active metabolite PRI-2191 on lung cancer cells having different genetic backgrounds. RESV and PRI-2191 showed divergent responses depending on the genetic profile of cells. Antiproliferative activity of PRI-2191 was noticeable in EGFRmut cells, while RESV showed the highest antiproliferative and caspase-3-inducing activity in KRASmut cells. RESV upregulated p53 expression in wtp53 cells, while downregulated it in mutp53 cells with simultaneous upregulation of p21 expression in both cases. The effect of PRI-2191 on the induction of CYP24A1 expression was enhanced by RESV in two KRASmut cell lines. The effect of RESV combined with PRI-2191 on cytokine production was pronounced and modulated. RESV cooperated with PRI-2191 in regulating the expression of IL-8 in EGFRmut cells, while OPN in KRASmut cells and PD-L1 in both cell subtypes. We hypothesize that the differences in response to RESV and PRI-2191 between EGFRmut and KRASmut cell lines result from the differences in epigenetic modifications since both cell subtypes are associated with the divergent smoking history that can induce epigenetic alterations.     

Effiziente Herstellung von Kohlenstofffasern

Efficient production of carbon fibres using new technologies Innovative process technologies for carbonization of precursor fibres, which can substitute conventional oven technologies and raise the efficiency of carbon fibre production are presented. The process technologies are based on the substitution of convective heat transfer by microwave plasma or direct fiber heating. In microwave-assisted plasma treatment, the heating of the fibres is carried out both by microwave absorption in the fibre volume and energy input into the fibre surface by means of the plasma species. During electrical carbonization, the fibres are heated by means of an electrical current flow. The processes can be used separately, one after the other (also in combination with conventional furnace technology) or as hybrid processes.     

Kinetic studies of water uptake and loss in glass-ionomer cements

The water sorption and desorption behaviour of three commercial glass-ionomer cements used in clinical dentistry have been studied in detail. Cured specimens of each material were found to show slight but variable water uptake in high humidity conditions, but steady loss in desiccating ones. This water loss was found to follow Fick’s law for the first 4–5 h. Diffusion coefficients at 22 °C were: Chemflex 1.34 × 10⁻⁶ cm² s⁻¹, Fuji IX 5.87 × 10⁻⁷ cm² s⁻¹, Aquacem 3.08 × 10⁻⁶ cm² s⁻¹. At 7 °C they were: Chemflex 8.90 × 10⁻⁷ cm² s⁻¹, Fuji IX 5.04 × 10⁻⁷ cm² s⁻¹, Aquacem 2.88 × 10⁻⁶ cm² s⁻¹. Activation energies for water loss were determined from the Arrhenius equation and were found to be Chemflex 161.8 J mol⁻¹, Fuji IX 101.3 J mol⁻¹, Aquacem 47.1 J mol⁻¹. Such low values show that water transport requires less energy in these cements than in resin-modified glass-ionomers. Fick’s law plots were found not to pass through the origin. This implies that, in each case, there is a small water loss that does not involve diffusion. This was concluded to be water at the surface of the specimens, and was termed “superficial water”. As such, it represents a fraction of the previously identified unbound (loose) water. Superficial water levels were: Chemflex 0.56%, Fuji IX 0.23%, Aquacem 0.87%. Equilibrium mass loss values were shown to be unaffected by temperature, and allowed ratios of bound:unbound water to be determined for all three cements. These showed wide variation, ranging from 1:5.26 for Chemflex to 1:1.25 for Fuji IX.     

Formation of bubbles and droplets in parallel, coupled flow-focusing geometries

This paper describes the mechanism of formation of bubbles of nitrogen in water containing Tween 20 as a surfactant, and of droplets of water in hexadecane containing Span 80 as a surfactant. The study of these microfluidic systems compares two or four flow-focusing generators coupled through shared inlets, supplying the continuous phase, and through a common outlet channel. The processes that form bubbles in neighboring generators interact for a wide range of flow parameters; the formation of bubbles alternates in time and space, and the bubbles assemble into complex patterns in the outlet channel. The dynamics of formation of bubbles in these systems are stable for long time (at least 10 min). For a certain range of flow parameters, the coupled flow-focusing generators exhibit two stable modes of operation for a single set of flow parameters. The dynamics of formation of droplets of water in hexadecane by the coupled flow-focusing generators are simpler--the adjacent generators produce only monodisperse droplets over the entire range of flow parameters that are explored. These observations suggest that the mechanism of interaction between coupled flow-focusing generators relies on the compressibility of the dispersed phase (e.g., the gas or liquid), and on variations in pressure at the flow-focusing orifices induced by the breakup of bubbles or droplets.     

Practical application of product design method robust to disturbances

Contemporary designed and manufactured products should meet a wide range of client requirements and expectations regarding quality for conditions of use in a life cycle. Therefore, design methods, which enable an optimal choice of product parameters by decreasing product sensivity to occurrence of some disturbances in a manufacturing process, become more and more significant in industrial practice. Such a behavior probably allows getting the lowest quality loss while keeping planned production costs. In this article, a new method of products design robust to disturbances exsisting in a technological process is presented. The application of mathematical modeling and methods of parameter estimation enabled formulating an approach in which parameters and acceptable tolerance of manufacturing product parameters are calculated. The efficiency of the proposed method was verified in the machine‐building industry with the example of designing parameters of a brushless direct current motor. © 2010 Wiley Periodicals, Inc.     

Circularly Polarized Dielectric‐Loaded Antennas: Current Technology and Future Challenges

In the last few years, dielectric loaded antennas (DLAs) have emerged as a viable solution for high‐gain reception at microwave frequencies for handheld devices such as satellite phones, radios, and global positioning systems. This article compares the performance, cost, and volumetric efficiencies of the two dominant designs, namely the dielectrically loaded quadrifilar‐helix and microstrip patch antennas. The current and future material requirements for DLAs are discussed and an example is given of a recently developed castable glass ceramic based on BiNbO₄, which is suitable in terms of properties and glass formability for the single‐step fabrication of net‐shape antenna cores.