Acute upper respiratory tract infections and indications for tonsillectomy in children. I. Immunoglobulin synthesis in the palatine tonsil tissue

Current viewpoints and practice concerning indications for tonsillectomy are presented. The annual specific risk for upper respiratory infection in children aged up to 15 is 1.1. The risk is higher in the youngest age group, in whom it rises to 1.8, decreasing with age and being lowest among children aged 12-15 years (0.5). The proportion of tonsillitis among acute upper respiratory tract infections is highest in the age group up to 3 years (36.9%); at the age of 4-5 years it is 37.1%, and is lowest among children aged 12-15 years (21.9%). The risk of tonsillitis caused by streptococci is highest among children aged up to 5 years. Statistical significance of differences in the synthesis of immunoglobulins (G, M, A and sA) and lysozymes in the palatine tonsil tissue of tonsillectomized children and healthy volunteers was tested by non-parametric tests for independent samples. Significant differences of the above mentioned syntheses were found in all entities studied. Any contribution to the documentation on the nature and cause of each tonsillitis in childhood is of great clinical value, because it is the only basis for rational consideration of indications for tonsillectomy.     

Enhanced Inhibition of Bladder Cancer Cell Growth by Simultaneous Knockdown of Antiapoptotic Bcl-xL and Survivin in Combination with Chemotherapy

The overexpression of antiapoptotic genes, such as Bcl-xL and survivin, contributes to the increased survival of tumor cells and to the development of treatment resistances. In the bladder cancer cell lines EJ28 and J82, the siRNA-mediated knockdown of survivin reduces cell proliferation and the inhibition of Bcl-xL sensitizes these cells towards subsequent chemotherapy with mitomycin C and cisplatin. Therefore, the aim of this study was to analyze if the simultaneous knockdown of Bcl-xL and survivin might represent a more powerful treatment option for bladder cancer than the single inhibition of one of these target genes. At 96 h after transfection, reduction in cell viability was stronger after simultaneous inhibition of Bcl-xL and survivin (decrease of 40%–48%) in comparison to the single target treatments (decrease of 29% at best). Furthermore, simultaneous knockdown of Bcl-xL and survivin considerably increased the efficacy of subsequent chemotherapy. For example, cellular viability of EJ28 cells decreased to 6% in consequence of Bcl-xL and survivin inhibition plus cisplatin treatment whereas single target siRNA plus chemotherapy treatments mediated reductions down to 15%–36% only. In conclusion, the combination of simultaneous siRNA-mediated knockdown of antiapoptotic Bcl-xL and survivin—a multitarget molecular-based therapy—and conventional chemotherapy shows great potential for improving bladder cancer treatment.     

Hybrid Dynamic Control Algorithm for Humanoid Robots Based on Reinforcement Learning

In this paper, hybrid integrated dynamic control algorithm for humanoid locomotion mechanism is presented. The proposed structure of controller involves two feedback loops: model-based dynamic controller including impart-force controller and reinforcement learning feedback controller around zero-moment point. The proposed new reinforcement learning algorithm is based on modified version of actor-critic architecture for dynamic reactive compensation. Simulation experiments were carried out in order to validate the proposed control approach.The obtained simulation results served as the basis for a critical evaluation of the controller performance.     

In situ image processing method to investigate performance and stability of dye solar cells

A simple and non-destructive method is introduced using image processing to investigate changes in the performance of the dye solar cells (DSCs). The main principle is based on the fact that the most important DSC components (dye, electrolyte, catalyst) have a specific color which often changes as result of degradation. Here the imaging technique is demonstrated in the case of exposing DSCs on very harsh conditions (85 °C temperature and UV + Visible light). The aging of the cells was recorded with a color sensitive camera in a well regulated setup and the photographs were processed using image analysis techniques. A key factor in making the imaging method quantitative and suitable for aging studies is color calibration which is explained in detail. The image analysis of different cell configurations revealed that the bleaching reactions of the electrolyte were related to reactions between TiO₂ and the electrolyte. The dye layer on the TiO₂ was shown slow down the degradation. Furthermore the comparison of image analysis and current–voltage curves indicated that the performance degradation of the cells was only partly due to loss of tri-iodide. The loss of photocurrent and photovoltage was apparently largely due to the harmful effect of the by-products of the bleaching and/or the degradation of the dye. In addition, a small recovery effect due to the generation of tri-iodide under reverse bias condition was seen in both image analysis and electrical measurements.     

Optical tweezers to measure the interaction between poly(acrylic acid) brushes

Optical tweezers are employed to measure the forces of interaction within single pairs of poly(acrylic acid) (PAA) grafted colloids with an extraordinary resolution of ±0.5 pN. Parameters varied are the concentration and valency of the counterions (KCl, CaCl₂) of the surrounding medium as well as its pH. The data are quantitatively described by a recently published model of Jusufi et al. [Colloid Polym Sci 2004; 282:910] for spherical polyelectrolyte brushes which takes into account the entropic effect of the counterions. For the scaling of the brush height a power law is found having an exponent of 0.25 ± 0.02 which ranges between the values expected for spherical and planar brushes. From the model the ionic concentration inside the brush is estimated in reasonable agreement with the literature.     

Effects of alkylresorcinols on volume and structure of yeast-leavened bread

BACKGROUND: Alkylresorcinols (AR) are amphiphilic phenolic compounds found in high amounts in wheat, durum wheat and rye, with different homologue composition for each cereal. The effect of different amounts of added AR from these cereals on bread volume, height, porosity and microstructure was studied. Breads with added rye bran (with high levels of AR) or acetone‐extracted rye bran (with low levels of AR) were also baked, as well as breads with finely milled forms of each of these brans. RESULTS: Breads with high amounts of added AR, irrespective of AR homologue composition, had a lower volume, a more compact structure and an adverse microstructure compared with breads with no or low levels of added AR. AR were also shown to inhibit the activity of baker's yeast. There was no difference in bread volume and porosity between bread baked with rye bran and acetone‐extracted rye bran or with brans of different particle size. CONCLUSION: Irrespective of homologue composition, AR had a negative effect on wheat bread properties when added in high amounts as purified extracts from wheat, durum wheat and rye. Natural levels of AR in rye bran, however, did not affect the volume and porosity of yeast‐leavened wheat breads. Copyright © 2010 Society of Chemical Industry     

Transition from the Steady to the Oscillatory Thermocapillary Convection in a Rectangular Container Under Various Cold Wall Temperature Effects

The transition from the steady to the oscillatory thermocapillary flow of high Prandtl number fluid in the rectangular container configuration under various cold wall temperatures effects have been studied experimentally. The fluid is heated by a thin wire placed along the free surface. The effects of buoyancy on the transport phenomenon are carefully assessed. The thermocapillary flow field is described based on a flow visualization and temperature measurement. The critical temperature difference for the onset of oscillations varies when the cold wall temperature is varied. The heat loss at the liquid free surface is identified to be responsible for this effect.     

Co-firing of biomass in coal-fired utility boilers

Co-firing tests with sawdust and coal have been carried out at FORTUM's Naantali-3 CHP power plant (315 MW_fuel). The Naantali-3 plant is a tangentially-fired pulverised-coal unit with a Sulzer once-through boiler that produces 79 MW electricity, 124 MW district heat and 70 MW steam. Naantali-3 is equipped with roller coal mills (Loesche), modern low-NO_x-burners (IVO RI-JET), over-fire air (OFA), electrostatic precipitator (ESP) and flue-gas desulphurization plant (FGD). Coal and sawdust were blended in the coal yard, and the mixture fed into the boiler through coal mills. Tests were carried out for three months during the April 1999 to April 2000 period with pine sawdust (50-65% moisture as received). During the tests, sawdust proportions of 2.5–8% (from the fuel input) were examined. The co-firing tests were successful in many ways, but the behaviour of the coal mills caused some problems, and therefore the simultaneous feed will not be the solution in a long-term use. Fortum has developed a new concept for co-firing coal and biofuels in large pulverised-coal fired boilers. The experiences gained from the Naantali co-firing tests and a good knowledge of low-NO_x burning and combustion behaviour of different fuels at Fortum, was used when the new co-firing concept was developed. This concept consists of a separate biofuel grinding system and bio- or bio-coal-burners. By using this system, it is possible to utilize many kinds of biofuels in PC-boilers as well as increase the share of biofuels, compared to the simultaneous feed of biofuel and coal.     

Hydrocarbon condensation in heavy-duty diesel exhaust

The semivolatile mass fraction of diesel exhaust particles was studied using size-resolved on-line techniques (DMA-ELPI; TDMA-ELPI). The average density of the semivolatile liquid on the particles was measured to be approximately 0.8 g/cm3. The measured size resolved values of mass transfer imply that condensation, or diffusion-limited mass transfer, plays a major role in driving the volatile matter to the diesel exhaust particles. The measured mass change values correspond to highly size dependent mass fractions for the semivolatile component, ranging from approximately 20-80%. Integrated over particle size distribution, the volatile mass fractions were 25 and 45% for the two load points studied. Calculation, based on the measured particle properties, indicates that only 10% volatile mass fraction could be explained by monolayer adsorption. The size resolved changes in particle effective density, fractal dimension, volatile mass fractions and mass are all in agreement with theoretical considerations of condensation.