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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.

Conventional methods of fabric inspection are tedious and require close association. In this work, digital image analysis for fabric assessment (DIAFA) is applied to modem and historic fabrics. Fabric images are divided into arrays of pixels with peak intensities distributed over gray scale ranges (histograms) and along constructed lines (line profiles). Fabric cover is measured by segmenting a histogram's B/w pixels, yarn spacing, and yarn thickness from moving point averages by calculating the breadth of a peak corresponding to an individual yarn at half the maximum peak height for a given line profile. The results show very good agreement with known values ( r = 0.919, n = 30, p < 0.01). Fourier power spectra provide facile measurements of yarn parameters in close agreement with the results from line profiling. With DIAFA, a small tool kit is developed to assist in the objective analysis of the structural integrity of fabrics in the museum environment, and it could be very useful in advancing automated fabric inspection.

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.

Conventional most probable number (MPN) methods seek a calculated value for microbial concentration (Δ, mL-1) which induces the total binomial probability function (Ptotal) to approach its maximum limit. In fact, such techniques are the only statistically compelling procedures available for determining MPN when utilizing a small set of observations per dilution (e.g., n = 3–8). However, as n approaches a large value, statistical routines which assume a normal distribution might be applied to ascertain the MPN. With this in mind, we produce herein a modified Gauss-Newton “linearization” (curve fitting) algorithm for determining Δ (n = 96) from binomial micro-plate assays which are readily automated using 96-well micro-plate readers. This technique, an iterative protocol, is less cumbersome than many traditional MPN procedures and has certain advantages. Data derived from this method were not only close to MPN estimations using a direct technique based on the conventional maximum probability resolution (MPR) concept but also displayed more favorable chi-squared (X2) statistics.

A method for estimating immobilized enzyme reaction progress curves, using simultaneous non-linear regression analysis of 2–3 substrate concentrations with time, is presented. These facile procedures involve using nested Gauss–Newton curve fitting algorithms on a Microsoft EXCEL spreadsheet. We refer to our technique as "nested" because the analysis consists of two or three mutually parameter-dependent sets of computations associated with bi- or termolecular enzyme-catalyzed reactions, respectively. We have applied the method to immobilized glucose oxidase-catalyzed reactions ([ d -glucose] and [O 2 ] with time) and found that the kinetic parameters from initial velocity data were similar to those determined by the nested curve fitting method discussed herein.

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.

A simplified explanation of the modified Gauss-Newton linearization (curve-fitting) procedure is presented by translating this algorithm into a spreadsheet with examples from various single- and multiple-pulse NMR experiments. Comparisons are made with linear regression analysis of mathematically manipulated data.

The structural organization of alkaline soluble peach pectin was investigated over size ranges extending from micrometers to tenths of nanometers. Analysis was by electron microscopy and high-performance anion-exchange chromatography (HPAEC). Superimposed and individual circular microgels in the micrometer size range were isolated from mesocarp tissue of cell walls and visualized by rotary shadowing. Dilute NaCl and 50% aqueous glycerol disaggregated these microgels into rods, segmented rods, and kinked rods, which collectively comprised the internal gel network of the microgels. Image analysis of the shadowed specimens before and after disaggregation followed by curve fitting of the smoothed distributions revealed a multimodal distribution of lengths. HPAEC revealed that the multimodal aggregates were stable for the most part to further dissociation by increasing ionic strength.

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.

By explicit calculation it is shown that the eigenfunctions of a particular Hamiltonian are complete. The Hamiltonian considered is that for a particle moving in one dimension with a Dirac delta function potential.

The first successful application of Faddeev-UPE theory to the binding energy of the ground state of three 4He atoms interacting through realistic intermolecular potentials is reported. (4He)3 is probably bound by about 0.1 K.

Laser-Raman spectra of L-α-dimyristoylphosphatidylcholine (DMPC) liposomes in the spectral range 1000–1200 cm −1 were obtained as a function of temperature from −80 to +50°C. The triplet found in this spectral region was resolved into Lorentzian components by means of an iterative computer program. The peak intensities, band widths, and band areas of the resolved 1062 cm −1 and 1130 cm −1 bands, assigned to CC stretching vibrations of trans segments, were evaluated as a function of temperature. While the peak intensities of the bands decrease substantially with temperature, the band widths show a considerable increase. The change in band areas is therefore smaller than the change in peak heights. Experiments with all trans carboxylic acids showed that in these compounds the area of the Raman bands at 1062 cm −1 and 1130 cm −1 is proportional to the number of trans bonds. The variation with temperature of the number of trans and gauche bonds in the studied phospholipid is reflected by the change of the area of the 1130 cm −1 Raman band.

Using 25 accurately known bond-stretching force constants and bond lengths for 23 molecules, a relation of the form: F = 37.3 r −5.35 has been obtained for carbon—nitrogen bonds. The root-mean-square deviation between the force constant values reported in the literature and those calculated from the equation above is 4.09 %. Fourteen of the molecules studied have a rotational symmetry axis that coincides with the carbon-to-nitrogen bond. The remaining molecules have lower symmetry. The observed force constant—bond length relationship gives quite satisfactory results for both groups of molecules.

On the basis of a Faddeev calculation, an Efimov state is predicted to exist in $^{4}\mathrm{He}_{3}$. This discovery represents the first manifestation of the Efimov effect and may have farreaching consequences in the statistical mechanics of $^{4}\mathrm{He}$ gas at low temperatures.