bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aldosterone blockade in post‐acute myocardial infarction heart failure
Authors: Pitt Bertram , Ferrari Roberto , Gheorghiade Mihai , van Veldhuisen Dirk J. , Krum Henry , McMurray John , Lopez‐Sendon Jose 
Published: June 2007

AbstractDevelopment of heart failure (HF) or left ventricular systolic dysfunction (LVSD) significantly increases mortality post acute myocardial infarction (AMI). Aldosterone contributes to the development and progression of HF post AMI, and major guidelines now recommend aldosterone blockade in this setting. However, lack of practical experience with aldosterone blockade may make clinicians hesitant to use these therapies. This review is based on a consensus cardiology conference that occurred in May 2005 (New York City) concerning these topics. Potential barriers to the use of aldosterone blockade are discussed and an algorithm for appropriate in‐hospital pharmacologic management of AMI with LVSD and/or HF is presented.
The Specification of Colour Appearance. I. Concepts and Terms
Authors: Hunt R. W. G. 
Published: June 2007

AbstractConcepts necessary for the specification of the appearance of colours are described, and the corresponding colour terms collected. Psychometric and psychoquantitative terms are listed that correlate with the perceptual and psychophysical terms used. The perceptual term colourfulness is proposed to denote the attribute of a visual sensation according to which an area appears to exhibit more or less chromatic colour; for a given chromaticity, as the luminance increases, colourfulness generally increases. For related colours, the CIE 1976 Colour Spaces are used to systematize some psychometric variables that are independent of absolute luminance level, including metric saturation, metric purity, and metric chroma, and formulae are given for calculating their amounts. (In Part II, to appear in the next issue, the effects of changes in viewing conditions will be discussed).
Additivity failures in heterochromatic brightness matching
Authors: Kaiser Peter K. , Wyszecki Gunter 
Published: June 2007

AbstractThe often poor correlation between luminance and perceived brightness has been attributed to the facts that first, the CIE standard luminous efficiency function V(Λ) does not represent adequately heterochromatic brightness matching of monochromatic stimuli, and second, the additivity law does not always hold in heterochromatic brightness matching. By means of a variation of the traditional experimental procedures, Guth found that two types of additivity failure can occur: additivity failures of the enhancement type and of the cancellation type. It is shown here that the two types of additivity failure can also be deduced by calculation from brightness‐matching data obtained by the traditional experimental procedure. However, the magnitude of the additivity failures and sometimes the type of failure seem to depend strongly upon the individual observers involved. New experimental data confirm Guth's results except in the middle region of the spectrum. Whereas Guth's observers find additivity failures of the cancellation type between 500 and 600 nm, the new data suggest that in that region additivity holds fairly well.
The Gamut of Real Surface Colours
Authors: Pointer M. R. 
Published: June 2007

AbstractA maximum gamut for real surface colours has been derived from the analysis of the colour coordinates of 4089 samples. The gamut has been derived in both the CIE 1976 L* u* v* colour space and the CIE 1976 L* a* b* colour space. The data are compared with the gamut produced by a typical dye set used in a photographic colour paper, and with the gamut of a typical television‐receiver display tube. Comparison with printing inks is difficult because of the large number available, but a large set of ink colours was used in deriving the maximum real‐colour gamut.
Who invented the color wheel?
Authors: Parkhurst Charles , Feller Robert L. 
Published: June 2007

AbstractPrevious research, published and unpublished, has shown that early references to color‐circle diagrams go back at least to 1611. Scientific records before that date trace four aspects of this history: circles based on seven colors, circles based on four colors, circles organized for a red‐yellow‐blue mixing system, and historical relationships between pigment primaries and spectral primaries. We conclude that color organization diagrams are at least as old as the 13th century, with the seven‐color circle possibly the oldest found, the four‐color next (14th‐15th centuries), and the red‐yellow‐blue circle the most recent (18th century). Each evidently rests on antecedent color theories. Although no graphic records of circular systems earlier than 1611 have yet been identified, some may be inferred from extant scientific texts and reconstructed.
Identification of organic pigments by solution spectrophotometry
Authors: Billmeyer Fred W. , Saltzman Max , Kumar Romesh 
Published: June 2007

AbstractOrganic pigments can be extracted readily into organic solvents from paints, plastics, inks, and other colored samples. If visible (in some cases near‐infrared) wave‐length spectrophotometric data are obtained from the resulting solutions using a log‐absorbance presentation, the pigments can be identified by matching curve shapes to those in a library of reference curves. Pigment identification is recognized as an important aid in industrial color matching. This article describes research leading to analytical schemes for the solution spectrophotometry of organic pigments, and to the development of an available library of reference curves. The advantages of the logabsorbance presentation are illustrated. A curve‐shape index is described for searching the reference library. The solution‐spectrophotometry method is compared with common alternatives; it is simple and rapid, usable on a micro scale, relatively free from interferences by other constituents of the samples, capable of identifying impure samples and the components of mixtures, and applicable with readily available equipment.
A proposal of new standard deviate observers
Authors: Nayatani Yoshinobu , Takahama Kotaro , Sobagaki Hiroaki 
Published: June 2007

AbstractThe method of singular‐value decomposition analysis of matrices is used to analyze the 20 color‐matching functions of Stiles's observers. It is confirmed that the 20 color‐matching functions are well reconstituted by the first three decomposed components. A new deviate observer is derived from the first decomposed component. It is shown that the new deviate observer can be used well in the computation of observer‐metamerism indices. Furthermore, an optimized deviate observer is developed by modifying the color‐matching functions of the new deviate observer slightly. Both the new and the optimized deviate observer give a basis for the further study of the evaluation of observer metamerism.
Brightness of colored self‐luminous displays
Authors: Kinney Jo Ann S. 
Published: June 2007

AbstractThis article summarizes the work of TC‐1.4 of the CIE in its attempt to improve the measurement of the quantity of light. It has become apparent in recent years that there are a number of instances in which two lights that measure the same do not look equally bright or have the same effectiveness for vision. These inconsistencies stem directly from our definition of light, radiant power evaluated by V(Λ), the luminous efficiency function of the human eye. since under certain conditions the use of this function to evaluate spectral irradiance may be inappropriate. A number of examples of the incorrect use of V(Λ) are given and particular emphasis is placed upon the evaluation of self‐luminous colored displays. A variety of techniques for solving the problems is discussed.
Trichromatic theories before young
Authors: Lang Heinwig 
Published: June 2007

AbstractTrichromatic theory is connected today with the names of Young and Helmholtz. But in the century before Young it had already become a widespread and intensely discussed issue in color science. This article shows (a) that trichromatic theories were so successful because their validity was strikingly demonstrated by the new technique of three‐color printing, (b) that trichromacy was believed to be a property of light and therefore seemed to contradict Newton's theory, (c) that the assumptions made to reconcile both theories remained unsuccessful, and (d) that Young's interpretation of trichromacy as being a consequence of the structure of our visual system was so inconvenient to contemporary scientific thought that another 50 years had to pass before it was accepted.
Color order systems and architectural color design
Authors: Spillmann Werner 
Published: June 2007

AbstractIn its first part, this article traces some outlines of the history of color order systems which bear upon the question of aesthetic color combinations (syntactic aspect). The second part defines the position of color in the field of architectural design (psychological, contextual, and structural aspect). The function and usefulness of color order systems in the process of architectural color planning and realization (pragmatic aspect) are discussed in the third and last part.
The fifteen causes of color: The physics and chemistry of color
Authors: Nassau Kurt 
Published: June 2007

AbstractThe fifteen causes of color derived from a variety of physical and chemical mechanisms are summarized in five Croups in this article. Vibrations and simple excitations explain the colors of incandescence (e.g., flames), gas excitations (neon tube, aurora), and vibrations and rotations (blue ice and water). Ligand‐field‐effect colors are seen in transition‐metal compounds (turquoise, chrome‐oxide green) and impurities (ruby, emerald). Molecular orbitals explain the colors of organic compounds (indigo, chlorophyll) and charge‐transfer compounds (blue sapphire, lapis lazuli). Energy bands are involved in the colors of metals and alloys (gold, brass), of semiconductors (cadmium yellow, vermillion), doped semiconductors (blue and yellow diamond), and color centers (amethyst, topaz). Geometrical and physical optics are involved in the colors derived from dispersive refraction (rainbow, green flash), scattering(blue sky, blue eyes, red sunset), interference (soap bubbles, iridescent beetles), and diffraction (the corona aureole, opal).
Judd's 1951 color‐mixture diagram
Authors: Fry Glenn A. 
Published: June 2007

AbstractVos demonstrated that the Judd 1951 color‐mixture diagram is a projective transformation of the CIE 1931 mixture diagram. He has provided transformation formulas for computing values of x′ and y′ from x and y, but he does not explain how the one set of data is derived from the other. Neither does Judd. Judd wanted the CIE to replace the 1931 V(Λ) curve with a new V(Λ) curve and to replace the 1931 XYZ diagram with a new X′Y′Z′ diagram. I have assumed that Judd started with the CIE 1931 RGB diagram. His X′Y′Z′ diagram can be derived from the RGB diagram if we use a different set of luminosity coefficients than those specified by the CIE. This change in luminosity coefficients was no doubt intended to compensate for the use of a new V(Λ) curve, but Judd has ignored the effect that this change in the luminosity coefficients should have on the alychne of the RGB diagram and the locus of spectral colors. This makes Judd's X′Y′Z′ diagram inappropriate for use in colorimetry and for use in building color‐vision models. I have proposed a new solution to this problem.
A model of colour vision for predicting colour appearance in various viewing conditions
Authors: Hunt R. W. G. 
Published: June 2007

AbstractA previously published model of colour vision predicted the hues, lightnesses, saturations, and chromas of colours seen under a medium photopic level of illumination. This model has now been extended to provide, in addition, predictions of brightness and colourfulness, for both related and unrelated colours, at any level of illumination, whether photopic, mesopic, or scotopic. The model has also been extended to cover a wider range of stimulus intensities and the use of various backgrounds.
Quantifying color appearance visually and instrumentally
Authors: Billmeyer Fred W. 
Published: June 2007

AbstractColor appearance can be measured visually or instrumentally. Visually, the color sample of interest is compared to similar samples from an atlas associated with an equally visually spaced color order system. The illumination, and thus chromatic adaptation, must be controlled, and simultaneous‐contrast effects must be avoided during the comparison. The task is thus quite different from the everyday evaluation of colors in a complex scene. If instrumental measurement is used, one of the recently developed models of chromatic adaptation must be combined with an appropriate model of color vision and an analytical description of an adequate uniform color space to provide measures of color appearance. Progress in solving these difficult problems, mostly documented in previous articles in this journal, is described in the present review article.
Color constancy and color rendering: Concomitant engineering of illuminants and reflectances
Authors: Brill Michael H. 
Published: June 2007

AbstractA strategy for cooperative illumination and reflectance design to produce color‐stable environments includes reduction of metamerism and paramerism, followed by attempts at color constancy. Given a model of color constancy based on linear basis‐function expansions of illuminant and reflectance spectra, all these goals could be served by designing reflectances and illuminants to inhabit certain compatible subspaces of spectral functions. Such linear models suggest two new indices of metamerism, one for designing illuminants and the other for designing reflectances. Implications are noted for designing color atlases. Finally, a physiological model of color constancy is described that is nonlinear and hence may add challenge to the concomitant design.
An artist's preference for the pope color system
Authors: Heila Ethel 
Published: June 2007

AbstractFor the practice of painting and for teaching color theory the Pope color system has distinct advantages over other color systems. Within the Pope color solid all the visual attributes of color are clearly represented and can be visually displayed depending on where the solid is sliced. This helps clarify color terminology and facilitates understanding color relationships. It also has practical advantages for the artist who must have some knowledge of color both conceptually and visually in order to realize the possibilities of their arrangement in a painting.
The effect of stimulus duration on the luminous efficiency functions for brightness
Authors: Tamura Tohru , Ikeda Mitsuo , Uchikawa Keiji 
Published: June 2007

AbstractSpectral luminous efficiency functions were obtained by direct heterochromatic brightness matching for four different stimulus durations: namely, 10‐ms, 200‐ms, 1‐s, and continuous presentation. The functions clearly changed in their shape, depending on the stimulus duration for two of three subjects. They showed usual double peaks at about 540 and 600 nm, which were greatly enhanced when the duration was 1 s. The enhancement decreased both with longer and shorter duration. Linear combinations of cone outputs model was applied to our results. The logR‐logG type mechanism in the long‐wavelength region and the logG‐logR‐logB type mechanism in the middle‐wavelength region were found for brightness perception. For the short‐wavelength region, by lifting up the short‐wavelength portion of the logR‐logG mechanism, luminous efficiency functions could be expressed. In the long‐ and middle‐wavelength region, the effects of the stimulus duration were explained by changing the negative input (originating from R or G cones) to the positive input as the stimulus duration increased from 10 ms to 1 s. The amount of the short‐wavelength sensitive cones' contribution in the middle‐wavelength region were small and there were no systematic changes for the stimulus durations. For the short‐wavelength region, the amount of the shift of the logR‐logG type mechanism was largest at the 1‐s duration.
Results of iscc questionnaire on metamerism. ISCC Committee on Indices of Metamerism
Authors: Billmeyer Fred W. 
Published: June 2007

AbstractAn analysis was made of the responses of nearly 300 color scientists and industrial colorists to a questionnaire circulated in 1982 by the Inter‐Society Color Council Project Committee on Indices of Metamerism. The responses to most of the questions were far from unanimous, with a consensus that occasionally included 90–95% of the respondents, but often with a strongly dissenting minority. In most responses the following major conclusions were evident: It was not possible for most respondents to separate the concept of color match from that of metamerism; in most instances, they were willing to accept that an approximate match was enough to allow the presence of metamerism; they confused the concept of metamerism, which defines a relation between two samples, with color constancy, a property of a single sample; they accepted identity of tristimulus values plus different spectral curves as a physical definition of metamerism, but they did not feel that this definition would solve all industrial problems; they felt that new terms and definitions were needed; and they considered color difference adequate as an index of metamerism, with total color difference the best descriptor, followed in order by differences in hue and chroma, the lightness difference being unimportant. Differences among industry groups, while occasionally significant, did not contradict any of these majority conclusions.
A fallacy in the definition of ΔH*
Authors: Huntsman James R. 
Published: June 2007

AbstractWhen a color differs from the reference, it is desirable to ascribe the difference to differences in the perceptual attributes of hue, chroma, and/or lightness through psychometric correlates of these attributes. To this end, the CIE has recommended the quantity ΔH* as a psychometric correlate of hue as defined by ΔH* = [(ΔE*)2 ‐ (ΔL*)2 ‐ (ΔC*)2]1/2, where the correlates correspond to either the 1976 CIELAB or CIELUV color spaces. Since ΔH* is defined as a “leftover,” this definition is valid only to the extent that ΔE* comprises exclusively ΔL*, ΔC*, and ΔH* and that ΔL*, ΔC*, and ΔH* are mutually independent compositionally, both psychophysically and psychometrically. It will be shown that as now defined ΔH* lacks psychometric independence of chroma and always leads to incorrect hue difference determination. Such a deficiency causes problems, especially in the halftone color printing industry, since it can suggest an incorrect adjustment for the hue of the inks. A revised definition herein of ΔH* provides a psychometric hue difference independent of chroma, valid for large and small psychometric color differences regardless of chroma. However, for small chromas, the seldom used metric ΔC might be a better color difference metric than ΔH* because complex appearance effects make the perceptual discrimination of lightness, chroma, and hue components more difficult than for high chromas.
Nulling of apparent motion as a method for assessing sensation luminance: An additivity test
Authors: Kaiser Peter K. , Vimal Ram L. P. , Cowan William B. , Hibino Haruo 
Published: June 2007

AbstractAn experiment was performed to test the additive properties of the Nulling of Apparent Motion Method. Small additivity failures were found, thus casting a theoretical question as to this method's role to measure sensation luminance. For practical purposes, the additivity failures were small enough to justify the use of this method.
Category effects in color memory
Authors: Boynton Robert M. , Fargo Lee , Olson Conrad X. , Smallman Harvey S. 
Published: June 2007

AbstractCategorical color perception has previously been tested using a naming method, and the data from 27 subjects so examined in several experiments have been combined to yield a “categorical color difference index” (CCDI) that can be computed for any pair of colors in the OSA set of 424 samples. A new experiment is performed in which categorical color perception is encouraged without the explicit use of names by allowing 10 seconds to elapse between the presentation of two stimuli before they are judged same or different. All of the colors being compared are either identical or nearest neighbors in the orange region of the OSA space. Nearest neighbors, which are separated by 2 OSA units, clearly differ when presented simultaneously; with the delay, errors (“same” responses) sometimes occur. These errors decrease as CCDI increases, suggesting that categorization occurs when colors must be remembered. Response time, on the other hand, is independent of CCDI and therefore may reflect color differences based upon discrimination, rather than identification.
Correlation between visual and instrumental colour differences of metallic paint films
Authors: Saris H. J. A. , Gottenbos R. J. B. , Van Houwelingen H. 
Published: June 2007

AbstractBecause of the importance of metallic paints particularly in the automobile industry, there is a need for colour measurement techniques which show a high correlation with visual judgments. The present study uses recently developed spectrophotometers with variable geometries to optimize this correlation. Visual and instrumental data have been analyzed by means of statistical techniques. The investigations have led to the conclusion that three different geometries are sufficient to describe the optical behaviour of metallic paint films, provided that the geometries are well distributed with respect to the angle between the direction of observation and the direction of the specular component. In addition to this measurement technique a calculation procedure has been developed that yields judgments that highly correlate with visual judgments.
Serial position curves for colored light patches
Authors: Avons S. E. , Daley Shelley A. 
Published: June 2007

AbstractPrevious studies have shown a distinction between short‐term and long‐term visual memory by measuring serial position curves for achromatic visual patterns. Three experiments are reported in which serial position curves were measured for homogeneous colored light patches displayed on a color monitor. In experiment 1 three color patches were displayed in series followed by reverse serial order recognition testing. Experiment 2 used the same paradigm but with different colors and with four items in the presentation series. The results of both experiments showed a recency effect confined to the last item, but no evidence of any primacy effect. These results correspond to those observed with achromatic patterns, suggesting that similar memory processes are used for color and pattern information. In experiment 3, the presentation series of four colors was followed by a single a recognition probe for one of these colors, chosen randomly. Under these conditions, the pronounced recency effect disappeared. The results are consistent with the view that both color memory and achromatic pattern memory utilise a voluntary visualization strategy. This has important implications for theories of visual memory, and practical issues concerning color matching by visual inspection.