SPECTRORADIOMETRY AND COLORIMETRY IN THE LIGHTING INDUSTRY

Spectroradiometry is fundamental in the measurement and evaluation of color. It is used in the evaluation of new light sources, in the analysis of problem areas, and for the compilation of data for inclusion in the technical brochures describing lighting products. The basic elements of a spectroradiometer are described and the application of spectral-power distribution measurements to photometry and colorimetry is illustrated.     

Quantification of Shrimp in Shrimp-Surimi Mixtures using Urea Gel Isoelectric Focusing

A method of quantitate the percent content by weight of shrimp in surimi-pink shrimp mixtures was developed by comparing peak areas of two Alaska pollock surimi-specific (pI 7.11 and 7.17) and two shrimp-specific (pI 5.46 and 5.52) protein bands on isoelectric focusing (IEF) gels. An equation describing the linear relationship between peak areas and protein from the standard samples of surimi, shrimp and surimi-pink shrimp mixtures was also developed. Using this method, unknown mixtures containing 10.0, 12.4 and 5.7% pink shrimp, respectively, were determined in blind studies to contain 8.3, 12.0 and 4.4% shrimp and 85.7, 86.8, and 92.7% surimi, respectively.     

Identification of Red Snapper (Lutjanus campechanus) using Electrophoretic Techniques

Isoelectric focusing (IEF), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and two-dimensional (2-D) gel electrophoresis were employed to produce protein profiles for species identification of red snapper and 11 other fish species. Comparing the distinctive patterns of water-soluble sarcoplasmic proteins for each species on IEF and SDS gels, red snapper could be identified. IEF gels of ampholyte mixture of 20% pH 3–10 and 80% pH 4–6.5 resolved better than gels with ampholyte ranging from pH 3–10, 4–6.5, 6–8, or 5–6 for species identification. The 10 and 12.5% SDS-PAGE gels produced more distinctive protein profiles for identification than 7.5 and 15% gels. Thus, these techniques could be applied to identify fish species.     

Preparation of Alkyl Esters of Pectin and Pectic Acid

Alkyl esters of pectin and pectic acid have been prepared via three different synthetic routes. Enhancements of intrinsic viscosity, binding to bile acids and to isolated soy protein were shown for these novel pectin derivatives. The development of new and improved pectin-containing products may be enhanced by the ease of preparation and improved functionality of such compounds.     

Diffraction from a Natural Grain Boundary in a Magnetite Bicrystal

The structure of a natural small-angle boundary in a magnetite bicrystal was investigated by X-ray diffraction. This boundary was a "general" type with a mixed twist and tilt character. The grain-boundary reflections observed around an 040 matrix reflection were in good agreement with those predicted by Boll-mann's O-lattice theory. These extra reflections appear to arise from a predominantly planar dislocation network. The structural width of the boundary, determined from the length of the relrods of the grain-boundary reflections, was of the order of four unit cells, close to the average spacing of the expected dislocation network.     

SIGNAL-DETECTION PERFORMANCE BY SUBJECTS DIFFERING IN PREDISPOSITION TO DAYDREAMING.

SS REPRESENTING EXTREMES ON QUESTIONNAIRES OF PRIOR DISPOSITION TO DAYDREAMING FREQUENCY AND THOUGHTFULNESS ALSO DIFFERED IN REPORTS OF TASK-IRRELEVANT IMAGERY DURING RAPID-RATE AUDITORY SIGNAL-DETECTION SESSIONS. WHILE HIGH DAYDREAMERS SHOWED A SIGNIFICANT PERFORMANCE DECREMENT OVER TIME IN GENERAL, THEY DID NOT SHOW SIGNIFICANTLY MORE DETECTION ERRORS THAN DID LOW DAYDREAMERS. RESULTS SUGGEST THAT DATA OBTAINED FROM QUESTIONNAIRE RESPONSES ARE RELEVANT TO PERFORMANCE IN AN EXPERIMENTAL SITUATION AND ALSO SUPPORT A MODEL RELATING DAYDREAMING TRENDS TO CERTAIN PATTERNS OF PREFERENCE FOR INTERNAL OR EXTERNAL STIMULATION EVEN UNDER RELATIVELY DEMANDING AND ALERTING CONDITIONS OF RAPID SIGNAL PRESENTATION. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

ON THE NEED FOR RELATIVISM.

"THE PSYCHOLOGY OF THE 1ST 1/2 OF THIS CENTURY WAS ABSOLUTISTIC, OUTER DIRECTED, AND INTOLERANT OF AMBIGUITY . . . .'RELATIVISTIC' REFERS TO A DEFINITION IN WHICH CONTEXT AND THE STATE OF THE INDIVIDUAL ARE PART OF THE DEFINING STATEMENT . . . . 19TH-CENTURY PHYSICS VIEWED MASS AS AN ABSOLUTE VALUE; 20TH-CENTURY PHYSICS MADE THE DEFINITION OF MASS RELATIVE TO THE SPEED OF LIGHT . . . .(PSYCHOLOGY) IS THREATENING TO ABANDON THE SECURITY OF THE DOCTRINE OF ABSOLUTISM OF THE STIMULUS EVENT. SUCH A REORIENTATION DEMANDS NEW MEASUREMENT PROCEDURES, NOVEL STRATEGIES OF INQUIRY, AND A GREATER TOLERANCE FOR AMBIGUITY." MANY EXAMPLES OF RELATIVISM ARE INDICATED UNDER THE TOPICS OF: THE CONCEPT OF SELF, SELF-DESCRIPTIVE LABELS, AND LEARNING AND ATTENTION. (29 REF.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Time-intensity Measurement of Flavor Release from a Model Gel System: Effect of Gelling Agent Type and Concentration

Flavor release from cornstarch, gelatin or iota carrageenan gels flavored with benzaldehyde, d-limonene or ethyl butyrate was measured at three gel strengths (soft, medium, firm) by 20 trained judges using the time-intensity (TI) method. At comparable gel strengths, starch and gelatin displayed greater flavor release properties than carrageenan, i.e., mean values for perceived maximum intensity (Imax) and total duration (Tdur) of flavor were higher for starch and gelatin than for carrageenan across flavors. Firm gelatin and carrageenan gels released flavor with a lower Imax than soft or medium gels, but Imax and Tdur did not vary across starch gel strengths. Results indicate both texture (firmness) and gelling agent affect flavor release from a gel.     

An Improved Enzyme Immunoassay for the Detection of Salmonella

An enzyme immunoassay (EIA) was developed for the detection of salmonellae in foods or other samples. This assay detected Salmonella contamination within two working days after initiation, and the EIA required <2 hr to perform. The test was sensitive and specific, showing virtually no cross reactivity to other organisms. No selective enrichment was found to be necessary, as the presence of other organisms, even in much greater numbers, had no effect on the reaction. The sensitivity is such that <10⁶Salmonella/mL were detected, and the food samples studied showed no effect on the background values and did not cause false readings.     

Two Distinct Pectin Fractions from Senescent Idared Apples Extracted Using Nondegradative Methods

After removal of water-soluble pectin from senescent Idared apples, an additional sizable pectin fraction could be extracted using Na₂EDTA under nondegradative conditions. This chelator-soluble fraction did not appear to owe its insolubility in the cell wall solely to molecular charge. The galacturonic acid-rich polymers of chelator-soluble pectin were notably lower in arabinose galactose and rhamnose residues than those of water-soluble pectin.