Sensitivities of ozone and fine particulate matter formation to emissions under the impact of potential future climate change

Impact of climate change alone and in combination with currently planned emission control strategies are investigated to quantify effectiveness in decreasing regional ozone and PM2.5 over the continental U.S. using MM5, SMOKE, and CMAQ with DDM-3D. Sensitivities of ozone and PM2.5 formation to precursor emissions are found to change only slightly in response to climate change. In many cases, mass per ton sensitivities to NO(x) and SO2 controls are predicted to be greater in the future due to both the lower emissions as well as climate, suggesting that current control strategies based on reducing such emissions will continue to be effective in decreasing ground-level ozone and PM2.5 concentrations. SO2 emission controls are predicted to be most beneficial for decreasing summertime PM2.5 levels, whereas controls of NO(x) emissions are effective in winter. Spatial distributions of sensitivities are also found to be only slightly affected assuming no changes in land-use. Contributions of biogenic VOC emissions to PM2.5 formation are simulated to be more important in the future because of higher temperatures, higher biogenic emissions, and lower anthropogenic NO(x) and SO2 emissions.     

Deactivation of tannin in high tannin milo by treatment with urea

Experiments were conducted to determine the effectiveness of urea in deactivating tannin in high tannin milo. High tannin milo (Pioneer B 815, 3.4 +/- .3% tannin) was reconstituted with aqueous urea solutions to give combinations of 26, 30, and 34% moisture with 2, 3, and 4% urea (percentage of urea per dry weight of milo). All treatments were maintained at 25 degrees C and were effective in deactivating tannin with no differences among moisture or urea content. The average rate of tannin deactivation was 68 +/- 2% d-1. Temperature affected rate of tannin deactivation in milo reconstituted to 30% moisture and 3% urea when stored at 25 or 60 degrees C. Rate of tannin deactivation was 44 +/- 5 and 89 +/- 18% d-1 at 25 and 60 degrees C, respectively. Tannin in high tannin milo can be deactivated rapidly and completely by reconstitution with aqueous urea. These studies demonstrate that tannin is deactivated completely under conditions where urea is an effective preservative of high moisture milo.     

High hydrostatic pressure treatment of finfish to inactivate Anisakis simplex

High hydrostatic pressure has been demonstrated to be a useful technique for treating food to reduce the number of pathogenic organisms and to extend shelf life. Most research in this area has focused on bacteria. However, a concern in the sashimi (raw fish) industry is that nematode worms such as Anisakis simplex occur naturally in cold-water marine fish. The objectives of this research were to perform a pilot study to determine the effect of high hydrostatic pressure on the viability of Anisakis simplex larvae, commonly found in king salmon and arrowtooth flounder, and to evaluate the effects of high hydrostatic pressure on the color and texture of the fish fillets. Pieces of fish (ca. 100 g per bag) containing 13 to 118 larvae were exposed to pressures of up to 80,000 lb/in2 (552 MPa) for up to 180 s. The times and pressures required to kill 100% of the larvae were as follows: 30 to 60 s at 60,000 lb/in2 (414 MPa), 90 to 180 s at 40,000 lb/in2 (276 MPa), and 180 s at 30,000 lb/in2 (207 MPa). For all salmon treatments that killed 100% of the larvae, a significant increase in the whiteness of the flesh was observed. Although high hydrostatic pressure was effective in killing A. simplex larvae in raw fish fillets, its significant effect on the color and overall appearance of the fillet may limit its application to the processing of fish for raw-fish markets.     

Lipid-protein interactions during dough development

Radionuclide-labelled glycerol triolein has been used to follow the fate of triglyceride lipids during the mixing of wheat flour doughs. After removal of residual free lipid by petrol extraction, initial fractionation of freeze-dried dough identified the acetic acid-soluble protein as being the only component involved significantly in work-induced lipid binding during dough development under nitrogen, and also in lipid release on admission of air. Very little labelled lipid was found in either the water-soluble proteins or the starch residue. Sub-fractionation of the acetic acid-soluble protein by ammonium sulphate precipitation from acetic acid-urea-cetyltrimethyl-ammonium bromide (AUC) solvent showed bound lipid to be distributed almost entirely between high-molecular-weight glutenin and protein which remained soluble in the AUC supernatant even in the presence of 20% ammonium sulphate. Precipitated gliadins contained very little labelled lipid. However, significant levels were found in classical ethanol-extracted gliadin, and were traced predominantly to the same supernatant-protein owing to its solubility in aqueous ethanol. Examination of this AUC-supernatant fraction showed it to contain a hitherto unreported protein which had a molecular weight of about 9000, was strongly complexed with tri-glyceride lipid on a 1:1 molar basis and showed a tendency to aggregate in solution. Its amino acid frequency was found to differ significantly from both glutenin and purothionin, the latter containing in particular very much more cysteine than the supernatant-protein. Representing 10% or more of the total gluten, this small, highly interactive protein is responsible for a significant, if not the major, part of lipid binding activity in dough and may well have a fundamental role in the formation of an insoluble glutenin structure through both —SH and hydrophobic interaction. Accordingly, the name ‘Ligolin’ is proposed, from the Latin ligare: to bind, to tie.     

The effect of lipoxygenase action on the mechanical development of doughs from fat-extracted and reconstituted wheat flours

The mechanism by which soya lipoxygenase enzyme action improves the Theological properties of wheat flour doughs during mechanical development in air has been investigated further. Free-lipid extraction, reconstitution and replacement experiments have shown that the rheological effect of lipoxygenase action, which is consistent with an oxidative improvement of the dough proteins and may also result in extended mixing tolerance, only occurred in the presence of an oxidisable, polyunsaturated, free-lipid substrate. Addition of this substrate in an oxidised state (produced either by autoxidation or enzyme-oxidation) to doughs mixed from fat-extracted flour under nitrogen resulted only in a small rheological improvement, greater for the autoxidised than the enzyme-oxidised lipid, but in no way comparable with the large rheological effect of lipoxygenase action during dough mixing in air. Furthermore, the presence of an antioxidant, nordihydroguaiaretic acid (NDGA), during dough development, although greatly inhibiting peroxide formation, only marginally impaired the rheological improvement due to lipoxygenase action. Additional evidence is therefore provided for a coupled oxidation mechanism being responsible for the rheological effect, since lipoxygenase-catalysed oxidation actively occurring in the dough during mixing appears to be the fundamental requirement, irrespective of whether the primary oxidation products lead to lipid peroxides or oxidised NDGA.     

Tin naphthalocyanine complexes for infrared absorption in organic photovoltaic cells

In this work, we examine the optical properties of tin naphthalocyanine dichloride (SnNcCl₂), and its performance as an electron donor material in organic photovoltaic cells (OPVs). As an active material, SnNcCl₂ is attractive for its narrow energy gap which facilitates optical absorption past a wavelength of λ = 1100 nm. We demonstrate a power conversion efficiency of η_P = (1.2 ± 0.1)% under simulated AM1.5G solar illumination at 100 mW/cm² using the electron donor–acceptor pairing of SnNcCl₂ and C₆₀ in a bilayer device architecture. While some phthalocyanines have been previously used to improve infrared absorption, this is often realized through the formation of molecular dimers. In SnNcCl₂, the infrared absorption is intrinsic to the molecule, arising as a result of the extended conjugation. Consequently, it is expected that SnNcCl₂ could be utilized in bulk heterojunction OPVs without sacrificing infrared absorption.     

Instrumental Measurement of Strain in Nonwoven Geotextile Fabrics

Geotextile fabrics and geomembranes are subjected to considerable compressive forces in situ, which may affect their fuuctional performance or lead to premature failure. The measurement of strain developed in such fabrics is therefore of considerable practical importance. A novel approach using a quantitative image analysis technique is described, which permits rapid and accurate measurement of the localised strains developed in nonwoven geotextile fabrics when subjected to compression by stones, gravel, or other hard materials. The technique is intended to be used in conjunction with the cylinder performance test which has been previously developed to simulate the strains imposed on geotextile fabrics in the ground.     

SELECTION OF SIGNAL PROCESSING TECHNIQUES FOR EXTRACTING QUANTITATIVE INDICATORS OF PASTE QUALITY FROM EXTRUSION PRESSURE DATA

Signal processing techniques have been developed for extracting quantitative indicators of the performance of extruders processing soft-solid pastes from the data recorded by pressure transducers located near the extrusion die. Such techniques have been applied previously to isothermal ram and screw devices using retrospective methods. This article reports on the scope for application of retrospective algorithms, ideally suited to ram extrusion, to continuous systems. Novel Bayesian methods for the detection of outliers were found to be unsuitable for real-time analysis, prompting the development of a gradient-based algorithm. A number of fractal analysis techniques for quantifying the paste homogeneity were assessed and proved to be less robust than indicators based on coefficient of variance. Periodic variations related to acute, circumferential fracture were readily identified by a Bayesian model-based approach. Application to practical systems is illustrated by tests on several different paste materials following theoretical investigations on numerically generated data.     

Invertebrate drift patterns in a regulated river: dams,periphyton biomass or longitudinal patterns?

Macroinvertebrate drift was sampled at 15 sites along the Tongariro River, New Zealand above and below two hydroelectric dams. Sixty‐seven invertebrate taxa were collected in the drift. Trichoptera (31) were the most diverse, followed by Diptera (13), Ephemeroptera (8) and Plecoptera (8). However, chironomidae were the numerically dominant taxa in the drift throughout the river and represented over 80% of all animals collected. Of these, Orthocladiinae and Diamesinae were the most abundant. Taxonomic richness declined with distance downstream and peaked at sites with intermediate levels of periphyton biomass. The per cent of Ephemeroptera, Plecoptera and Trichoptera (EPT) was 3–4 times higher in the unregulated section of the river and declined exponentially with both distance downstream and increase in periphyton biomass, but densities were similar along the river. Of the measured environmental variables periphyton biomass was most closely linked with drift community structure. Periphyton biomass was six times higher in the lower section of the river than the upper unregulated section. The autocorrelation between periphyton biomass and distance downstream complicates the interpretation of results. However, because of the distinct differences between above and below dam sections of river in periphyton biomass and the strong link between it and invertebrate drift we suggest that the alteration of flow patterns by the hydroelectric dams and the associated shift in periphyton biomass is the most likely explanation for invertebrate drift patterns in the river. Copyright © 2009 John Wiley & Sons, Ltd.     

Detection of growth factor binding to gelatin and heparin using a photonic crystal optical biosensor

Drug–carrier interactions are important to protein controlled release systems to protect the protein from denaturation and ensure properly timed release. A novel photonic crystal biosensor was used to investigate a gelatin–protein controlled release system to determine the amount of protein bound to the carrier at physiological conditions. The Biomolecular Interaction Detection (BIND) system reflects a narrow band of wavelengths when white light is shone incident to the grating. As mass is deposited onto the surface, the peak wavelength value is shifted due to changes in the optical density of the biosensor. The BIND system was used to detect the binding of growth factors onto acidic gelatin, basic gelatin, and heparin on the sensor surface. Through a series of experiments, including functionalizing the sensor, adjusting the ionic strength of the solution, adjusting the substrate concentration, and minimizing non-specific signal, the adsorption of the gelatins and heparin on the sensor was enhanced. The binding interaction of recombinant human transforming growth factor (rhTGF)-β1 and bone morphogenetic protein (rhBMP)-2 with the two types of gelatin and heparin were investigated. The strength of the interaction between rhTGF-β1 and the substrates is in the following order: heparin > acidic gelatin > basic gelatin. RhBMP-2 bound to the substrates but with less intensity than TGF-β1: heparin > basic gelatin > acidic gelatin. This work provides support for the controlled release mechanism through degradation of the gelatin carrier.