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Wool fabrics treated for shrinkage control by applying a novel two-step ARS process3 involving an activated peroxide bleach followed by enzyme treatment were dyed at lower temperatures within shorter dyeing times than conventional dyeing with acid dyes which require 90 ° C or higher for 60 minutes or longer. The shrinkage control process involved bleaching pretreatment with dicyandiamide in alkaline hydrogen peroxide and with gluconic acid additive at 30 ° C (86 ° F) for 30 minutes followed by sulfite-assisted serine protease treatment for biopolishing and shrinkage prevention at 45 ° C (113 ° F) for 40 minutes. Dye uptake with time over the temperature range of dyeing showed that untreated fabrics and pretreated fabrics exhibited sigmoidal dyeing behavior with exhaustion within 55–70 minutes at 55–60 ° C. Fabrics pretreated and subsequently treated with enzyme exhibited exponential dyeing behavior with exhaustion within 20–30 minutes at 30–55 ° C. We attributed low temperature dyeing with reduced dyeing times to changes in wool morphology and chemical structure as documented by both scanning electron and confocal fluorescent microscopy. The ARS process provides shrinkage control with greater ease of bleaching and dyeing.

In this manuscript we present a modified kinetic model for pathogen capture efficiency (E) variation with mixing time (Tmix) which is applicable for most combinations of immuno-magnetic bead (IMB)-target organism concentrations (e.g., [IMB] ˜ 8 × 106 IMB mL-1; Salmonella enterica serovar Enteritidis, [SE] ˜ 102-108 CFU mL-1). We found that as the ratio of [IMB] to [SE] was decreased from more than 105 to ca. 10-1, the average number of cells captured per IMB SE complex increased from ca. 1 to 4 ± 1. Concurrently, using a modified kinetic model for fitting E variation with Tmix, the maximum possible level of capture (§) was observed to decline from ˜ 100% (§˜ 1; [IMB] > > [SE]) to 23% (§˜ 0.23; [IMB]:[SE] ˜ 0.1). Using a purely kinetic approach we also found that an empirical mass transport term (yobs= (3.1 ± 1.2) × 10-9 mL IMB-1 min 1; averaged across all [SE] tested: [IMB]:[SE] ˜ 200000, 200, 3, and 0.1) did not differ much from yobs reported in earlier work (3.35 ± 0.2 × 10-9 mL min-1 IMB-1) at extremely low [SE] (e.g., ± 100 CFU mL-1). Upon inserting the classically-derived equation for γ into the kinetic model and solving for the effective IMB radius (rIMB), we found that the rIMB was 2.3 ± 0.16 μ (§ S; averaged across all [IMB]:[SE]) which was only 0.5–0.9 μ greater than the rIMB reported by the manufacturer (1.4 ± 0.2 μ). These results support previous work which showed a similar small rIMB deviation possibly due to the hydro-dynamic behavior of the IMBs in relatively dilute buffer suspensions ([IMB ˜ 8 × 106 IMB mL-1) and argues that IMB-based cell capture is almost exclusively a function of mass transport.

Size distributions of extracts derived from starch were investigated to aid in elucidating structure-function relationships of these polymers in water. Starch granules derived from waxy maize and amylomaize VII were dissolved in water by microwave heating in a high pressure vessel. Transmission electron microscopy of starch deposited from dilute solution and rotary shadowed with platinum, revealed that amylopectin imaged from waxy maize could be broadly classified as about 28% circular space filling patches containing branched clusters and 72% asymmetric linear containing branched clusters. Lengths of asymmetric linear amylopectin components ranged from about 37 to 980 nm whereas the diameter of circular amylopectin components ranged from about 44 to 200 nm. Although the starch in amylomaize VII is about 70% amylose, its narrow asymmetric structure when visualized by microscopy enabled us to image amylose even though amylopectin was present. Lengths of components ranged from about 46 to 254 nm. After smoothing and curve fitting, we found that all size distributions investigated could be treated as if they were multimodal in nature. The most abundant amylose component had a linear density of 8.2 × 103 molar mass units/ nm. This value could be explained if amylose had an aggregation number of about 5.9.

High-performance, size-exclusion chromatography columns were calibrated in average root-mean-square radii of gyration (μ R gz ) by a combination of commercial “narrow” pullulan and “broad” dextran standards. The nonlinear calibration-curves were fitted by a computer-aided, iterative, least-squares procedure. Values of (μ R gz ), obtained from a point-by-point transformation of the respective pullulan and dextran chromatograms by utilizing universal calibration, were compared with inputted μ R gz calibration values. For standards ranging in μ R gz value from 20.1 to 389 A, the accuracy ranged from 1 to 15.3%. Furthermore, from relationships in the literature, μ R gz values were transformed to μ M w . These values of μ M w were comparable to, but generally less accurate than, μ M w values from direct, molecular-weight calibration.