Short-term power sources for tokamaks and other physical experiments

The Compass-D tokamak is being planned to move from UKAEA Culham (England) be and reinstalled in IPP Prague (Czech Republic). An overview of Compass-D energetics is described in short. The new power sources have to be designed. Alternative solutions of power sources have been investigated. Ignitrons and mechanical breakers can be replaced by modern high-power semiconductors. With respect to the need of accumulated energy, new technologies of energy storage - supercapacitors and high-speed flywheels, not applied up to now in similar fusion projects, are characterized in comparison with traditional ones - capacitors and big motor-flywheel generators. It is shown that these technologies enhance possibilities in arrangement of power supplies for tokamaks as well as for other high-power demanding experiments with pulse length from fraction to tens of seconds.     

Sensitivity to Cisplatin in Head and Neck Cancer Cells Is Significantly Affected by Patient-Derived Cancer-Associated Fibroblasts

Cancer-associated fibroblasts (CAFs) are one of the most abundant and critical components of the tumor stroma. CAFs can impact many important steps of cancerogenesis and may also influence treatment resistance. Some of these effects need the direct contact of CAFs and cancer cells, while some involve paracrine signals. In this study, we investigated the ability of head and neck squamous cell carcinomas (HNSCC) patient-derived CAFs to promote or inhibit the colony-forming ability of HNSCC cells. The effect of cisplatin on this promoting or inhibiting influence was also studied. The subsequent analysis focused on changes in the expression of genes associated with cancer progression. We found that cisplatin response in model HNSCC cancer cells was modified by coculture with CAFs, was CAF-specific, and different patient-derived CAFs had a different “sensitizing ratio”. Increased expression of VEGFA, PGE2S, COX2, EGFR, and NANOG in cancer cells was characteristic for the increase of resistance. On the other hand, CCL2 expression was associated with sensitizing effect. Significantly higher amounts of cisplatin were found in CAFs derived from patients who subsequently experienced a recurrence. In conclusion, our results showed that CAFs could promote and/or inhibit colony-forming capability and cisplatin resistance in HNSCC cells via paracrine effects and subsequent changes in gene expression of cancer-associated genes in cancer cells.     

High‐Pressure Thermal Sterilization: Food Safety and Food Quality of Baby Food Puree

The benefits that high‐pressure thermal sterilization offers as an emerging technology could be used to produce a better overall food quality. Due to shorter dwell times and lower thermal load applied to the product in comparison to the thermal retorting, lower numbers and quantities of unwanted food processing contaminants (FPCs), for example, furan, acrylamide, HMF, and MCPD‐esters could be formed. Two spore strains were used to test the technique; Geobacillus stearothermophilus and Bacillus amyloliquefaciens, over the temperature range 90 to 121 °C at 600 MPa. The treatments were carried out in baby food puree and ACES‐buffer. The treatments at 90 and 105 °C showed that G. stearothermophilus is more pressure‐sensitive than B. amyloliquefaciens. The formation of FPCs was monitored during the sterilization process and compared to the amounts found in retorted samples of the same food. The amounts of furan could be reduced between 81% to 96% in comparison to retorting for the tested temperature pressure combination even at sterilization conditions of F₀‐value in 7 min.     

Application of A4F-MALS for the Characterization of Polymers Prepared by Emulsion Polymerization: Comparison of the Molecular Structure of Styrene-Acrylate and Methyl Methacrylate-Acrylate Copolymers

In this paper, organic asymmetric flow field flow fractionation coupled to a multi-angle light scattering detector is presented as a very efficient tool for the characterization of copolymers prepared by emulsion polymerization. The molar mass distribution and the extent of branching of styrene–acrylate copolymers have been compared with corresponding copolymers of methyl methacrylate. It has been found that the presence of acrylate monomer results in the increase of molar mass and formation of branched macromolecules due to intermolecular chain transfer to polymer similarly as in case of methyl methacrylate–acrylate copolymers. However, the effect is far less pronounced.     

A Novel Insight into the Cardiotoxicity of Antineoplastic Drug Doxorubicin

Doxorubicin is a commonly used antineoplastic agent in the treatment of many types of cancer. Little is known about the interactions of doxorubicin with cardiac biomolecules. Serious cardiotoxicity including dilated cardiomyopathy often resulting in a fatal congestive heart failure may occur as a consequence of chemotherapy with doxorubicin. The purpose of this study was to determine the effect of exposure to doxorubicin on the changes in major amino acids in tissue of cardiac muscle (proline, taurine, glutamic acid, arginine, aspartic acid, leucine, glycine, valine, alanine, isoleucine, threonine, lysine and serine). An in vitro interaction study was performed as a comparison of amino acid profiles in heart tissue before and after application of doxorubicin. We found that doxorubicin directly influences myocardial amino acid representation even at low concentrations. In addition, we performed an interaction study that resulted in the determination of breaking points for each of analyzed amino acids. Lysine, arginine, β-alanine, valine and serine were determined as the most sensitive amino acids. Additionally we compared amino acid profiles of myocardium before and after exposure to doxorubicin. The amount of amino acids after interaction with doxorubicin was significantly reduced (p = 0.05). This fact points at an ability of doxorubicin to induce changes in quantitative composition of amino acids in myocardium. Moreover, this confirms that the interactions between doxorubicin and amino acids may act as another factor most likely responsible for adverse effects of doxorubicin on myocardium.     

Comments on Campbell's "Reforms as experiments."

Comments on D. T. Campbell's (see record 1969-17253-001) article on the scientific evaluation of social reform and argues that the "authentic exchange of role" is important in a socialist society. When evaluating the result of reform, the opinion of the recipients is usually taken into account. Social reforms as planned social changes could be arranged so that the participants could exchange their roles with the reformers and vice versa. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

在实时控制系统中通过FlexRay同步多种器件

让我们设想这样一个控制系统:其中多个器件用于对模拟数量进行抽样,一个强大的中心器件用于处理测量值并计算控制操作,还有另外一些器件用于生成控制信号.它的一个实例就是4轮汽车主动减震系统,其传感器和驱动器件置于车轮附近,控制器位于中央位置.所有器件使用同一个通信系统.要实现这些目的,可使用FlexRay等时分多址(TDMA)通信协议(参考文献1).     

Easy to use and rapid isolation and detection of a viral nucleic acid by using paramagnetic microparticles and carbon nanotubes-based screen-printed electrodes

A method that is easy to use, rapid, with a low cost of detecting viral nucleic acid in a biological sample represents the essential tool in targeted therapy. In this study, we report the use of paramagnetic microparticles covered by streptavidin and modified by an oligonucleotide probe with a specific viral sequence labeled by biotin to detect human immunodeficiency virus (HIV) and influenza virus subtype H5N1. The viral nucleic acids were primarily detected by adsorptive transfer stripping technique coupled with square wave voltammetry using carbon paste, hanging mercury drop or carbon nanotubes-based screen-printed working electrodes. Detection limits were estimated for both sequences down to picograms per 3 μl. To isolate the viral sequences, paramagnetic microparticles covered with biotin-labeled oligonucleotides were used. We calculated the yield of isolation for H5N1 and/or HIV sequences, which was defined as “isolated concentration of viral nucleic acid sequence”/“given viral nucleic acid sequence” × 100. We estimated the yield for both sequences as 59%. Moreover, we studied the influence of human serum, dsDNA and non-complementary sequence of nucleic acids on isolation of viral nucleic acids. We also used carbon nanotubes-based screen-printed electrodes coupled with micro-flow instrument to detect viral nucleic acids. We were able to isolate and detect nanogram amounts of nucleic acids.