Partial inhibition of cholesterol oxides formation in frozen fish pre-treated with a plant extract

The formation of cholesterol oxide products (COPs) in frozen horse mackerel ( Trachurus trachurus ) fillets was studied. The effect of pre-treating the fish by soaking (45 min) in either of two concentrations of the aqueous solution of an antioxidant plant extract prior to the freezing step was determined. The fish fillets were sampled immediately after freezing and at intervals along 12 months of frozen storage (−20 °C). Two control groups consisting of untreated and water-treated fish were stored and sampled under the same conditions. During the experiment, qualitative analysis revealed the formation of the following COPs: 7α-hydroxy-cholesterol, 7β-hydroxy-cholesterol and 7-keto-cholesterol. All treatment groups showed an increase ( P  < 0.05) in the content of all three COPs with storage time. As a result of pre-freezing antioxidant treatment, COPs formation was reduced ( P  < 0.05) in comparison with both control samples. This partial inhibition was consistent with a longer shelf-life time as revealed by sensory analysis.     

Multivariate statistical analysis of botrytised wines of different origin

The study examined several types of compounds can be suitable to characterise wines made from botrytised grapes and to determine their origin and authenticity. Amines, acids, macro- and microelements of botrytised sweet wine specialities, coming from Hungary and different countries, were analysed. Measured values of twenty-one Tokaji aszú wines and twenty-three foreign botrytised wines were compared by multivariate statistical methods. Characterising the effect of Botrytis cinerea and the winemaking technology, amines were the most suitable components for determination of authenticity and origin of wines from the three types of compounds studied. However, in acids and elemental composition, differentiation of wine samples by principal component analysis was not complete but a tendency can be observed for separation according to origin. The knowledge on composition of acids and elements can support the results of amine analysis in reaching the goal to determine the origin of wines.     

Microbiological investigation of an industrial ultra pure supply water plant using cultivation-based and cultivation-independent methods

Ultra pure waters (UPW), characterized by extremely low salt and nutrient concentrations, can suffer from microbial contamination which causes biofouling and biocorrosion, possibly leading to reduced lifetime and increased operational costs. Samples were taken from an ultra pure supply water producing plant of a power plant. Scanning electron microscopic examination was carried out on the biofilms formed in the system. Biofilm, ion exchange resin, and water samples were characterized by culture-based methods and molecular fingerprinting (terminal restriction fragment length polymorphism [T-RFLP] analysis and molecular cloning). Identification of bacteria was based on 16S rDNA sequence comparison. A complex microbial community structure was revealed. Nearly 46% of the clones were related to as yet uncultured bacteria. The community profiles of the water samples were the most diverse and most of bacteria were recruited from bacterial communities of tube surface and ion exchange resin biofilms. Microbiota of different layers of the mixed bed ion exchange resin showed the highest similarity. Most of the identified taxa (dominated by β-Proteobacteria) could take part in microbially influenced corrosion.     

The h-index of h-index and of other informetric topics

In this paper we examine the applicability of the concept of h-index to topics, where a topic has index h, if there are h publications that received at least h citations and the rest of the publications on the topic received at most h citations. We discuss methodological issues related to the computation of h-index of topics (denoted h-b index by BANKS [2006]). Data collection for computing the h-b index is much more complex than computing the index for authors, research groups and/or journals, and has several limitations. We demonstrate the methods on a number of informetric topics, among them the h-index.     

Key Parameters in the Production of Medieval Luster Colors and Shines

Lusters of different color and reflectivity were obtained under controlled conditions in a laboratory using medieval recipes. In this study, we analyze the influence of paint recipes, glaze compositions, and thermal paths and atmospheres on the final aspect and characteristics of the Ag/Cu nanocomposite layer formed. The colors and reflectivity of the medieval lusters were successfully reproduced using the cinnabar-containing recipes as basic luster paints. X-ray diffraction, Optical UV-Vis spectra, and microprobe chemical analysis were carried out to determine the composition and the nature and size of the nanoparticles and their relationship with their optical properties.     

Conductive composites prepared via a propagating polymerization front

A novel material, a conducting composite with variable temperature coefficient of electrical conductivity, was prepared in a propagating front of an addition polymerization. Graphite and zinc particles were incorporated into an acrylamide-triethylene glycol dimethacrylate copolymer. Specific electric resistance values of the materials yielded were measured at room temperature and also conductivity measurements were performed in the range of 20–220°C. The basic recipe was modified by doping the conductive composite materials with microscopic-scale-size particles of several inorganic and organic compounds, resulting in significantly different conductivity features of the composite. Scanning electron microscopy was performed to study the morphology of materials yielded. No percolative patterns containing zinc particles were found to support the conductive behavior of the composite. In accordance with to the modifying effect of doping materials we suspect that the acrylamide-triethylene glycol dimethacrylate copolymer plays a specific role in the electric conductivity behavior of the composite material.     

Effect of TiO2 and 11 minor elements on the reactivity of ground-granulated blast-furnace slag in blended cements

Ground-granulated blast-furnace slags (GGBS) are glasses (>99%) of the CaO-Al₂O₃-SiO₂ compositional system and are widely used as supplementary cementitious materials. Differences in reactivity of GGBS were screened by modifying the content of 12 minor elements (namely Ba, Ce, Cs, Cr, K, Mn, P, Sn, Sr, Ti, V, and Zr). Scanning electron microscopy observations showed that most elements entered the silicate glass matrix, only Sn was reduced to its metallic form and P accumulated in minor minerals. Mortar strength tests showed that 2 day compressive strength was reduced by >50% for a TiO₂ content of 2.5 wt% in the slag. At 28 days the loss in compressive strength was still >40%. Calorimetric tests on other element additions showed that the content of network modifiers (Ba, Cs, K and Sr) and GGBS reactivity are positively correlated, whereas Ce, Cr, V, and Zr significantly decreased reactivity. Finally, it is shown that these effects can be estimated by the concentration and the weighted field strength of the added element.     

青稞酒发酵过程中生物胺动态变化

对青稞酒发酵过程中生物胺的动态变化规律进行研究。利用氨基酸自动分析液相色谱法测定青稞酒不同发酵阶段中7种生物胺的含量,来评价发酵环境以及控制合理发酵过程和发酵终产物的质量。结果表明：青稞原料中不含组胺,但是青稞酒醅及成品青稞酒中都含有组胺。传统发酵和多菌种发酵两种发酵方式青稞酒的生物胺含量变化规律是：腐胺及胍丁胺的含量变化随着发酵的进行呈下降趋势;组胺及酪胺的含量随发酵进程逐渐上升,尤其是酪胺,上升趋势明显,多菌种发酵由2.98μg/g上升至5.36μg/g,传统发酵由5.97μg/g 上升至11.67μg/g。其余各种生物胺含量变化不明显,发酵过程的生物胺总量变化也不显著。本实验检测的青稞酒醅中的生物胺总量范围在53.44～72.56μg/g,不存在生物胺安全问题。