A NEW APPROACH TO CATEGORY SCALES OF INTENSITY I: TRADITIONAL VERSUS RANK-RATING

A traditional approach to intensity scaling, using ratings on a 9-point category scale was compared to a method that combined elements of ranking called Rank-Rating. The latter method forced judges to retaste stimuli whose tastes they had forgotten and accordingly reduced discrimination errors, thus increasing ability to discriminate.     

RATIO SCALES AND CATEGORY SCALES OF ODOUR INTENSITY

The relation between a ratio scale obtained by magnitude estimationand a category scale of the odour intensity of 1-butanol wasstudied, together with individual variations in the ratio scale.Series of solutions of butanol in water in small bottles werepresented to a panel for judgement, half using the method ofmagnitude estimation, the other half a category scale. Plotswere made of the category scale against the ratio scale, andthe ratio scales of individual members of the panel were analysed.A power function exponent of 0.48 was found for the panel'sratio scale, with individual values ranging from 0.25 to 0.49.The category scale was curved relative to the ratio scale; variabilityof the magnitude estimates was approximately proportional tothe magnitude estimates; and a small time-order error was found.Odour intensity exhibits the three tested characteristics ofa prothetic continuum, and the variability of individual exponentswas not as great as sometimes suggested.     

A NEW APPROACH TO CORRECTION OF D-LOOP TRANSPOSITION OF THE GREAT ARTERIES

An operative procedure is described for repair of transposition of the great arteries in which the left ventricle is the "aortic" ventricle and the right ventricle is the "pulmonic" ventricle. The technical feasibility of this procedure is supported by its successful application in experimental animals. A modified procedure, which may be applicable in certain complex forms of transposition of the great arteries and other perplexing anomalies for which there are no known repairs, is discussed.     

SYNTHETIC FLAVORS: A NEW APPROACH TO EFFICIENCY AND SAFETY

More than 1000 volatile synthetic flavor compounds are GRASfood additives. Comprehensive toxicological testing to assuretheir safety would be prohibitive in cost. Instead, their numbermight be logically reduced to a few dozen by applying thesecriteria: (1) Measurement of normal odor detection threshold,to eliminate weakly odorous compounds. (2) Assessment with specificallyodor blind persons, to delete compounds having very similarodors. As an example, 12 lower fatty acids on the permittedlist range over 2700-fold in their thresholds, yet they belongto the same sweat-like primary odor. Hence they could be replacedby just one among their number, isovaleric acid, which has thestrongest and sweatiest odor. Analogous reasoning is appliedto three new primary odors: the spermous odor of 1-pyrroline,the fishy odor of trimethylamine, and the malty odor of isobutyraldehyde.In each case the number and quantity of flavor additives requiredin food could be substantially reduced by using the more effcientprimary odors. This should result in improved safety for theconsumer.     

SCANNING ELECTRON MICROSCOPY: A NEW APPROACH TO THE DESMIDIACEAE

A camera lucida drawing, light and SEM micro-graphs of Cosmarium botrytis are contrasted with the intent of showing the advantages of SEM in systematic and morphological investigations. Several developmental questions amenable to an approach with SEM have arisen.     

ADJUSTING TASTE SCORES FOR VARIATIONS IN USE OF SCALES

A method is given for adjusting the scores of tasters when continuous graphicrating scales are used. Linear adjustments are made for both the location and scale differences of tasters.