Fluorescent modification of serum albumin by lipid peroxidation

Peroxidation of fatty acids bound to human serum albumin results in the production of fluorescent chromophores in the protein when it is stored in the liquid, powdered or crystalline state. Peroxidizing polyunsaturated fatty acid esters, and carbonyls derived from peroxidizing lipids react with amino groups of protein to give products that have fluorescence spectra very similar to those observed for stored commercial preparations of serum albumin.     

Predicting runoff-induced pesticide input in agricultural sub-catchment surface waters: linking catchment variables and contamination

An urgent need exists for applicable methods to predict areas at risk of pesticide contamination within agricultural catchments. As such, an attempt was made to predict and validate contamination in nine separate sub-catchments of the Lourens River, South Africa, through use of a geographic information system (GIS)-based runoff model, which incorporates geographical catchment variables and physicochemical characteristics of applied pesticides. We compared the results of the prediction with measured contamination in water and suspended sediment samples collected during runoff conditions in tributaries discharging these sub-catchments. The most common insecticides applied and detected in the catchment over a 3-year sampling period were azinphos-methyl (AZP), chlorpyrifos (CPF) and endosulfan (END). AZP was predominantly found in water samples, while CPF and END were detected at higher levels in the suspended particle samples. We found positive (p<0.002) correlations between the predicted average loss and the concentrations of the three insecticides both in water and suspended sediments (r between 0.87 and 0.94). Two sites in the sub-catchment were identified as posing the greatest risk to the Lourens River mainstream. It is assumed that lack of buffer strips, presence of erosion rills and high slopes are the main variables responsible for the high contamination at these sites. We conclude that this approach to predict runoff-related surface water contamination may serve as a powerful tool for risk assessment and management in South African orchard areas.     

100% Clean Energy: The California Conundrum

The state of California has embarked on an ambitious effort to achieve very high levels of clean energy in the interest of minimizing greenhouse gas (GHG) emissions. California Senate Bill 100 (SB100), enacted in September 2018, increased the statewide required Renewable Portfolio Standard (RPS)¹ for electric utilities from 50% to 60% by 2030. It further established an aspirational goal of 100% clean energy in all sectors by 2045. Achieving 60% to 70% or more in the electric sector is projected to be achievable at reasonable cost, if current planning assumptions prove true.However, getting all the way to the ideal 100% is a different matter, based on current technology projections, system configurations and costs. The challenges are two-fold. First, what to do with the renewables over-generation that will inevitably occur when necessarily large levels of installed and non-dispatchable renewable capacity produces in hours when there is no need for it?Second, without backup from fossil resources, reliability of the electric grid is a risk. Batteries have a bright future in helping integrate the intermittency of renewable resources on an hourly operating basis going forward. But at currently-projected storage durations and costs, the projected cost of using batteries to ensure installed resource adequacy and grid reliability in a 100% renewable, zero-fossil world is prohibitive without further technological advances and associated cost reductions.This article describes the unique challenges for California and potential solutions for them as the quest for 100% clean energy in California and other states continues.     

High temperature solar electrothermal processing—Zinc from zinc oxide

We examined the feasibility of using sunlight to reduce the amount of electric power and/or fossil fuel needed to win metals from their ores and other compounds. The uniqueness of highly concentrated sunlight as a source of high-temperature process heat makes it attractive. We also examined, in some detail, ZnO as a candidate substance for exploratory experimental studies. We have mapped out, in temperature-pressure coordinates, the properties of the working substance and the thermodynamic performance of an archetype device as a guide to the temperature-pressure regime in which experimental studies might most profitably be undertaken.     

Behaviour of lead electrodes in sulphate electrolytes. I. Effect of electrode preparation on discriminant curve cyclic voltammograms

A new technique called discriminant curve cyclic voltammetry (DCCV) has been developed to study the cycling behaviour of battery plate materials. The method is used to investigate the effect of various electrode pretreatments on the cycling behaviour of pure lead in sulphate electrolytes. It is found that three distinctive patterns of response are observed depending upon the surface condition of the lead. The results are correlated with photographic evidence obtained by scanning electron microscopy.     

A mechanical analysis of the physical bonding properties of soft lining materials to PMMA

The bonding properties of soft liners to acrylic denture bases are characterized by their variable resistance to external loading. This resistance depends on the nature of the load, the chemistry and mode of polymerization of the liner, and the topography of the acrylic surface to which the liner is applied. The results obtained indicate that heat-curing acrylic soft liners are superior to silicone rubber materials; and that light smoothing of the acrylic surface prior to processing the liner has a beneficial effect on bonding.     

Recovery of Salmonella from retail broilers by a whole-carcass enrichment procedure

Fresh whole broiler carcasses were purchased from grocery stores over a 20-week period. Carcasses were selected on the basis of their having intact packages and unique U.S. Department of Agriculture (USDA) plant numbers and sell-by dates, such that each bird represented a single processing plant-processing day combination. Carcasses were tested for Salmonella with a rinse aliquot obtained after whole-bird incubation in the rinse media for 24 h. On the basis of the number of unique processing plants (USDA plant numbers) and expiration dates involved, the number of birds available each week ranged from 6 to 17. Over the 20-week period, 251 independent carcasses from 14 processing plants were tested. The percentages of carcasses testing positive for Salmonella ranged from 0 (for 1 week) to >60% (for 3 weeks). For only 4 of the 20 weeks was an incidence of Salmonella-positive carcasses of <20% found. For the entire 20-week study, 85 (33.9%) of the 251 carcasses tested were found to be Salmonella positive. For those processing plants from which >10 carcasses were obtained, the percentages of carcasses testing positive for Salmonella ranged from <20 (two plants) to >40% (four plants). These results indicate that a whole-carcass enrichment may be more sensitive for the detection of Salmonella-positive carcasses than the traditional whole-carcass rinse followed by immediate testing of a subsample aliquot when small numbers of Salmonella are expected.     

Inference by Eye: Confidence Intervals and How to Read Pictures of Data.

Wider use in psychology of confidence intervals (CIs), especially as error bars in figures, is a desirable development. However, psychologists seldom use CIs and may not understand them well. The authors discuss the interpretation of figures with error bars and analyze the relationship between CIs and statistical significance testing. They propose 7 rules of eye to guide the inferential use of figures with error bars. These include general principles: Seek bars that relate directly to effects of interest, be sensitive to experimental design, and interpret the intervals. They also include guidelines for inferential interpretation of the overlap of CIs on independent group means. Wider use of interval estimation in psychology has the potential to improve research communication substantially. (PsycINFO Database Record (c) 2010 APA, all rights reserved)