Identification of the origin of commercial enological tannins by the analysis of monosaccharides and polyalcohols

The monosaccharide and polyalcohol composition of 28-samples of different commercial tannins, including oak wood, grape seed and skin, plant gall, chestnut, quebracho and gambier, has been evaluated by gas chromatography–mass spectrometry after derivatization into their trimethylsilyl ethers. Quercitol was found to be characteristic of oak tannins, whereas gall plant tannins could be differentiated by their content of pinitol. Myo-inositol and arabitol were detected in tannins from quebracho. These polyalcohols, together with muco-inositol and chiro-inositol, were found in tannins from chestnut while bornesitol was found to be characteristic of tannins from gambier. Monosaccharide composition also helped to distinguish among tannin origins: arabinose, xylose, fructose and glucose were quantified in oak, quebracho and chestnut tannins, whereas only fructose and glucose were detected in plant gall and grape tannins. These results imply that the qualitative study of monosaccharides and polyalcohols could help to determine and control the authenticity of enological tannins.     

DETERMINATION OF β-GLUCAN IN WORT AND BEER BY ITS BINDING WITH CALCOFLUOR,USING A FLUORIMETRIC FLOW-INJECTION-ANALYSIS (FIA) METHOD

The FIA-fluorimetric methods for the determination of β-glucan in worts and beers have been investigated, modified and improved. Fluorescence is excited by using a mercury lamp and a 338 nm band-pass excitation filter, and detected using a 425 nm long-pass emission filter. It has been found that an increase of the ionic strength of the eluent, up to a maxium of 1% Sodium Chloride, increases the range of β-glucan molecular weights effectively bound by Calcofluor. The influence of the low molecular weight components of wort and beer: dextrins, aminoacids, etc, has been studied and found that their effect is negligible. The interference of wort and beer colour on the measurement of β-glucan has been quantified and several approaches are given to overcome it. Thirty-six European beers have been analyzed for β-glucan content. The possible detection of the addition of exogenous β-glucanases to wort and beer is discussed.     

Disconnecting outcomes and evaluations: The role of negotiator focus.

Three experiments explored the role of negotiator focus in disconnecting negotiated outcomes and evaluations. Negotiators who focused on their target prices, the ideal outcome they could obtain, achieved objectively superior outcomes compared with negotiators who focused on their lower bound (e.g., reservation price). Those negotiators who focused on their targets, however, were less satisfied with their objectively superior outcomes. In the final experiment, when negotiators were reminded of their lower bound after the negotiation, the satisfaction of those negotiators who had focused on their target prices was increased, with outcomes and evaluations becoming connected rather than disconnected. The possible negative effects of setting high goals and the temporal dimensions of the disconnection and reconnection between outcomes and evaluations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nanocrystallization of Fe73.5Si13.5B9Nb3Cu1 soft-magnetic alloy from amorphous precursor in a magnetic field

The effect of a magnetic field on the nature of nanocrystallization from a melt-spun Fe_73.5Si_13.5B₉Nb₃Cu₁ amorphous precursor has been studied with the aim of controlling microstructures and magnetic properties. Annealing for magnetic crystallization was carried out at temperatures between the Curie temperature of the amorphous phase (586 K) and that of the crystalline phase (920 K). It was found that the {110} texture component in crystallized α-Fe(Si) phase increased in importance with increasing magnetic-field strength. An X-ray diffraction analysis based on the Shultz method revealed that the magnetic field caused preferential formation of {110}-oriented nuclei. In addition, the applied field enhanced crystallization kinetics, particularly the nucleation rate. No significant difference in grain growth behavior was observed as a result of applying a magnetic field. We therefore conclude that the development of the {110} texture by magnetic crystallization is predominantly attributable to preferential nucleation, rather than preferential growth, of {110}-oriented nuclei. The saturation magnetization of nanocrystallized specimens, evaluated using a vibrating sample magnetometer (VSM), was increased by the application of a magnetic field up to 4T during nanocrystallization.     

Computer-based automation of concentration measurements with ion-selective electrodes

An integrated computer system consisting of an expandable ionanalyzer and a PC has been used to automate concentration measurements with ion-selective electrodes (ISEs). The ionanalyzer determines ionic concentrations using a reference electrode coupled with an ISE. The measurements and calibrations are carried out in a thermostated sample changer equipped with a flow cell. The data obtained by the ionanalyzer are sent via a standard RS 232-C interface to a microcomputer. In this paper, we describe the automatic data acquisition system and the subsequent processing of the measurements. One program (Transorion) automatically collects the measurements carried out by the ionanalyzer, giving a real-time graphic representation of the measurement on the computer screen. A second program (Graforion) facilitates the management of the data stored by the first program, and listing and graphics of these can be obtained on the printer/plotter. The method has been used to study continuous concentration changes in an aqueous solution of potassium iodide.     

High-Fat Diet Alters Serum Fatty Acid Profiles in Obesity Prone Rats: Implications for In Vitro Studies

High‐fat diets (HFD) are commonly used in rodents to induce obesity, increase serum fatty acids and induce lipotoxicity in various organs. Invitro studies commonly utilize individual free fatty acids (FFA) to study lipid exposure in an effort to model what is occurring in vivo; however, these approaches are not physiological as tissues are exposed to multiple fatty acids in vivo. Here we characterize circulating lipids in obesity‐prone rats fed an HFD in both fasted and fed states with the goal of developing physiologically relevant fatty acid mixtures for subsequent in vitro studies. Rats were fed an HFD (60 % kcal fat) or a control diet (10 % kcal fat) for 3 weeks; liver tissue and both portal and systemic blood were collected. Fatty acid profiles and absolute concentrations of triglycerides (TAG) and FFA in the serum and TAG, diacylglycerol (DAG) and phospholipids in the liver were measured. Surprisingly, both systemic and portal serum TAG were ~40 % lower in HFD‐fed compared to controls. Overall, compared to the control diet, HFD feeding consistently induced an increase in the proportion of circulating polyunsaturated fatty acids (PUFA) with a concomitant decline in monounsaturated fatty acids (MUFA) and saturated fatty acids (SFA) in both serum TAG and FFA. The elevations of PUFA were mostly attributed to increases in n‐6 PUFA, linoleic acid and arachidonic acid. In conclusion, fatty acid mixtures enriched with linoleic and arachidonic acid in addition to SFA and MUFA should be utilized for in vitro studies attempting to model lipid exposures that occur during in vivo HFD conditions.     

Integrating community engagement and children's voices into design and planning education

This article shares outcomes from a year-long participatory planning process – one that brought together children and youth engagement, city planning, campus planning, and a university environmental design course to explore child-friendly, dense and affordable housing for a city of approximately 100,000 residents. This process of engagement asked design students to include youth participation and child-friendly cities as an integrated component of sustainable cities. The article shows varying degrees of transformation, views of children as credible participants, and values gained from the project. Many undergraduates changed their thinking about the role of young people in design processes and outcomes.     

Spectral study and classification of worldwide locations considering several multijunction solar cell technologies

Multi‐junction solar cells are widely used in high‐concentration photovoltaic systems (HCPV) attaining the highest efficiencies in photovoltaic energy generation. This technology is more dependent on the spectral variations of the impinging Direct Normal Irradiance (DNI) than conventional photovoltaics based on silicon solar cells and consequently demands a deeper knowledge of the solar resource characteristics. This article explores the capabilities of spectral indexes, namely, spectral matching ratios (SMR), to spectrally characterize the annual irradiation reaching a particular location on the Earth and to provide the necessary information for the spectral optimization of a MJ solar cell in that location as a starting point for CPV module spectral tuning. Additionally, the relationship between such indexes and the atmosphere parameters, such as the aerosol optical depth (AOD), precipitable water (PW), and air mass (AM), is discussed using radiative transfer models such as SMARTS to generate the spectrally resolved DNI. The network of ground‐based sun and sky‐scanning radiometers AErosol RObotic NETwork (AERONET) is exploited to obtain the atmosphere parameters for a selected bunch of 34 sites worldwide. Finally, the SMR indexes are obtained for every location, and a comparative analysis is carried out for four architectures of triple junction solar cells, covering both lattice match and metamorphic technologies. The differences found among cell technologies are much less significant than among locations. Copyright © 2016 John Wiley & Sons, Ltd.     

Experimental study and modelling of an azo colourant dynamic adsorption onto functional cross-linked chitosan/ceramic particles in a fixed bed column

The use of azo dyes in industrial activities generates a large volume of contaminated wastewater; these pollutants in water bodies affect aquatic biota and human health. A functional biocomposite sorbent material was synthesized using cross-linked chitosan with oxalic acid that forms a coating on alumina ceramic particles (AOCh). The removal of Reactive Red 195, a reactive azo dye, using a fixed-bed adsorption column filled with this material was tested. AOCh was physico-chemically characterized by Fourier transform infrared spectroscopy–total attenuated reflection (FTIR-ATR), scanning electron microscopy–energy dispersion spectrometry X-ray (SEM-EDS), X-ray diffraction (XDR), thermo-gravimetric analysis (TGA), and Z-potential. The dynamic adsorption performance was analyzed from experimental breakthrough curves obtained in fixed-bed columns by modifying different operating conditions (bed depth, volumetric flow rate, and dye inlet concentration). Equilibrium adsorption isotherms were determined under dynamic conditions and compared with batch results. The maximum adsorption capacity of the dynamic equilibrium isotherm obtained from the continuous assays was 331 mg/g; this value was the highest in comparison to other tested materials reported in the literature. Different dynamic adsorption models were applied to fit experimental data, including Thomas, Bohart–Admas, Yoon–Nelson, logistic general model, bed depth surface time (BDST), and modified dose response (Yan) models. A critical analysis of these equations was presented, showing the equivalences and the relationship among the coefficients. The Yan model achieved the highest level of agreement between the experimental and predicted values of the breakthrough curves. The use of this model enables scaling-up the industrial process for dye removal. The present work proposed a novel biosorbent material and contributes to the analysis of industrial dye removal under dynamic conditions.