Yeast diversity investigation of wine-related samples from two different Slovakian wine-producing areas through a multistep procedure

A multistep procedure was applied in order to investigate the yeasts diversity during the must fermentation of two wine varieties Frankovka Modra (Blaufränkisch) and Veltlinske Zelene (Grüner Veltliner) from two different Slovakian wine-producing areas. The procedure combined a cultivation step with a PCR-based selection step (f-ITS PCR; fluorescence internal transcribed spacer 2 polymerase chain reaction), and a final identification step oriented to the sequencing of ITS1-5.8S rDNA-ITS2 region of the selected yeasts. The strategy demonstrated to be suitable for the rapid analysis of a large panel of isolates. The f-ITS PCR was able to discriminate the isolated yeasts by one PCR run and capillary electrophoresis separation. The investigation showed the presence of non-Saccharomyces strains on grapes and during the initial and middle stages of must fermentation. Members of the genus Saccharomyces appeared only during the middle fermentation stage and they were the predominant species until the final phase of the process. The presented simple and reliable multistep procedure can be useful for the investigation of the yeast microflora from any wine-producing area and also for studying other kinds of food environments.     

DockVis: Visual Analysis of Molecular Docking Trajectories

Computation of trajectories for ligand binding and unbinding via protein tunnels and channels is important for predicting possible protein–ligand interactions. These highly complex processes can be simulated by several software tools, which provide biochemists with valuable information for drug design or protein engineering applications. This paper focuses on aiding this exploration process by introducing the DockVis visual analysis tool. DockVis operates with the multivariate output data from one of the latest available tools for the prediction of ligand transport, CaverDock. DockVis provides the users with several linked views, combining the 2D abstracted depictions of ligands and their surroundings and properties with the 3D view. In this way, we enable the users to perceive the spatial configurations of ligand passing through the protein tunnel. The users are initially visually directed to the most relevant parts of ligand trajectories, which can be then explored in higher detail by the follow-up analyses. DockVis was designed in tight collaboration with protein engineers developing the CaverDock tool. However, the concept of DockVis can be extended to any other tool predicting ligand pathways by the molecular docking. DockVis will be made available to the wide user community as part of the Caver Analyst 3.0 software package ( www.caver.cz ).     

The influence of dopants on loss tangent of polycrystalline alumina ceramics

Polycrystalline aluminas with various concentrations of oxide dopants CaO, MgO, and TiO₂, ranging from 0.05 wt.% to 5 wt.%, as well as pure alumina references were prepared by slip casting from suspensions with various solid loading (30, 35, and 40 vol.% of Al₂O₃), and sintered at 1350 °C for 1 h as low loss tangent electroceramics. As the key parameter for intended application the loss tangents were measured at room temperature in the frequency range between 1 and 200 kHz. In the case of pure alumina the lowest value of loss tangent was achieved in the materials with minimum residual porosity. The values of loss tangents of doped materials were influenced by the concentration of dopants. The addition of 0.05 and 0.5 wt.% of MgO and CaO decreased the value of loss tangent in the whole frequency range. The effect was related to more homogenous microstructure with lower concentration of defects (pores) resulting from the addition of dopants. The increased values of loss tangent in the materials with higher level of additives (5 wt.%) are related to lower density of the materials, and the presence of residual porosity. Other contributing factors are the formation of secondary phases (calcium, magnesium and titanium aluminates), and the increased concentration of lattice defects due to incorporation of atoms with different valencies to alumina crystal lattice.     

Advantageous mechanochemical synthesis of copper(Ⅰ)selenide semiconductor,characterization,and properties

Copper(I)selenide-nanocrystalline semiconductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball mill.The kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se mixtures.The X-ray diffraction confirmed the orthorhombic crystal structure of Cu₂Se with the crystallite size～25 nm.The surface chemical structure was studied by X-ray photoelectron spectroscopy,whereby the binding energy of the Cu 2p and Se 3d signals corresponded to Cu⁺and Se^2?oxidation states.Transmission electron microscopy revealed agglomerated nanocrystals and confirmed their orthorhombic structure,as well.The optical properties were studied utilizing ultraviolet-visible spectroscopy and photoluminescence spectroscopy.The direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size effect.This type of Cu₂Se synthesis can be easily adapted to production dimensions using an industrial vibratory mill.The advantages of mechanochemical synthesis represent the potential for inexpensive,environmentally-friendly,and waste-free manufacturing of Cu₂Se.     

Rational Pricing of Water as an Instrument of Improving Water Use Efficiency in the Agricultural Sector: A Case Study in Gujarat,India

The agricultural sector in India accounts for over 85% of the total water used for various purposes in the country. However, the efficiency of water use in agriculture is very low, approximately 40% for surface irrigation and 60% for groundwater irrigation. Part of the reason for the low efficiency is the highly subsidized price of irrigation water that encourages the excessive application of water to crops. This paper is based on a case study conducted in the command area of a public irrigation canal in the state of Gujarat, India. It attempts to explore the role of the rational pricing of canal irrigation water in motivating farmers to use water judiciously and thereby enhance the water use efficiency in irrigated agriculture. The paper contends that farmers are sensitive to an increase in irrigation water charges, but unless the administered price is increased to the level that would prevail in a free market, it will not have its intended effect on irrigators.     

SiN/bamboo like carbon nanotube composite electrodes for lithium ion rechargeable batteries

A dual stage technique employing hot filament chemical vapor deposition (HFCVD) and radio frequency sputtering was used to synthesize SiN/BCNTs (bamboo like carbon nanotubes) on copper substrates. The films were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Electron field emission studies (EFE), charge-discharge, and cyclic voltammetry. The comprehensive characterization is consistent with a nanolayer of amorphous SiN on BCNTs. Field emission experiments confirm the excellent contact of the SiN nanolayer with the surface of the BCNTs necessary for fabrication of a coin cell. Electrochemical testing shows that SiN/BCNT electrode can deliver an initial discharge capacity of 2000 mAh g⁻¹ which is higher than the capacity of graphite and the reversible capacity after ten cycles is 300 mAh g⁻¹. The cyclic voltammetry results suggest good reversibility with Li during cycling.     

Culture-independent detection of microorganisms in traditional Slovakian bryndza cheese

In order to investigate the microflora of Slovakian bryndza cheese (a cheese containing unpasteurized or pasteurized ewes' milk component) by a culture-independent method, DNA was extracted directly from 7 bryndza samples and analysed by an innovative method. Using the universal prokaryotic and fungal primers, ribosomal DNA internal transcribed spacer (ITS) regions with variable length were amplified. The standard universal reverse primer L1 aligning to bacterial 23 s rDNA was found unsuitable for some lactic acid bacteria and other species based on in silico analysis. Therefore, L1 primer was replaced by a combination of novel primers GplusR and GminusR aligning to the adjacent, more conserved DNA region. The amplification profiles were visualised by both standard electrophoresis and by fluorescent capillary gel electrophoresis. From representative samples, major amplicons were excised from the gel, cloned and sequenced. Sequencing revealed that the samples contained Lactobacillus delbrueckii, Lactobacillus brevis, Streptococcus thermophilus, Lactococcus lactis, Lactococcus raffinolactis, Streptococcus macedonicus, Leuconostoc pseudomesenteroides, Debaromyces hansenii, Mucor fragilis, Yarrowia lipolytica and Galactomyces geotrichum. These results represent an extension of the knowledge on the microflora of Slovakian bryndza cheese. The introduced automated ribosomal DNA intergenic spacer analysis of the bacterial and fungal genomes proved to be very effective in the application of studying microflora of cheese.     

Simultaneous Determination of Phenolic Acids and Scopoletin in Brandies Using Synchronous Fluorescence Spectrometry Coupled with Partial Least Squares

Brandy, a spirit drink produced from wine (grape), is rich in phenolic acids due to its maturation in wooden barrels. Phenolic acids play a significant role in defining the sensorial characteristics of wines and brandies, and therefore, it is very useful to determine them. Synchronous fluorescence spectra of mixtures containing phenolic acids (gallic, vanillic, syringic and ferulic) and scopoletin have been used for the determination of these compounds by partial least squares (PLS)2. Synchronous fluorescence spectra were collected by simultaneously scanning the excitation and emission monochromator in the excitation wavelength range 200–500 nm, with constant wavelength difference 100 nm between them. The leave-one-out cross-validation method was used to select the optimum number of five PLS2 components (latent variables). The PLS2 model captured for 100 % of variance in the spectral block, and it accounted for 99.34 % of variance in the concentration block. The performance of the model was evaluated by means of root mean square error of cross-validation, root mean square error of prediction and coefficient of determination. The best model was used for the determination of the above-mentioned compounds in brandy samples at concentration levels 2–74 mg L^?1 for phenolic acids and 0.06–0.43 mg L^?1 for scopoletin. The PLS2 results were found to be in good agreement with those obtained by HPLC method.     

Dietary advanced glycation endproducts (AGEs) and their health effects--PRO

Thermal processing of food results in the formation of various novel compounds, among others advanced glycation endproducts (AGEs). AGEs result from nonenzymatic glycation reactions between reducing sugars and free amino groups of proteins, peptides, or amino acids. Due to their potential noxious effects, alimentary AGEs are also called glycotoxins. This review provides a summary of the available evidence on the health effects of exaggerated intake of thermally treated food. Data from experimental studies in rodents and from clinical studies in healthy volunteers and in patients suffering from selected diseases in which AGEs are of pathogenetic importance (diabetes, chronic renal failure) are summarized. It is concluded that, an exaggerated intake of thermally processed foods may exert in vivo diabetogenic and nephrotoxic effects, induce low-grade inflammation, enhance oxidative stress, and promote atherosclerosis.