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PubMed2002

The relationship between raw broiler breast meat color and composition.

Experiments were conducted to compare the chemical composition of broiler breast meat that was naturally lighter than normal, normal, and darker than normal. In each of three separate replicated trials (wk), fillets were obtained from three commercial processing plants. Approximately 25 fillets of each color group were selected based on International Commission on Illumination (CIE) lightness values as follows: lighter than normal (L* > 53), normal (48 < L* < 51), and darker than normal (L* < 46). The fillets from each replicate, plant, and color group were ground and mixed together, and samples for the 27 treatment groups subjected to color, pH, and chemical analyses (protein, ash, moisture, total lipids, iron, glycogen, and fatty acids profile). The whole fillets had significantly different color values for the three color groups at 0 and 24 h prior to grinding. Of the ground meat samples, there were significant treatment and plant differences in composition. There were no color treatment effects on moisture, lipid, glycogen, iron, ash, or fatty acid ratios. Meat from the light group had significantly lower protein values than the normal or dark meat and lower ash than the dark group. The light group also had significantly higher levels of C16:1 and lower levels of C18:0 and C20:4 fatty acids than the dark group. Among the three plants, there were significant effects for breast meat color and composition. Results indicated that, although plant had more effect on composition, differences by color group might indicate that extreme variation in color may be due to long-term genetic factors as well as short-term antemortem stress.

Animals↗

PubMed1987

Effect of filters upon object color naming.

Color constancy refers to the phenomenon that the perceived colors of objects are largely unaltered by changes in the illuminant or by viewing through colored filters. Deviations from perfect constancy, induced by filters similar to ophthalmic tints, were investigated in this study. Munsell color chips were forced-choice categorized into R, Y, G, or B. This accurately located the boundaries between these colors on the chip color circle. Testing was performed through 23 different adaptive conditions and chromaticity shifts created by filters. The technique simulates real world situations in which the chromaticity of the objects and the adaptation of the observer both change. Generally, color constancy held quite well. The boundaries between the four colors shifted for some filters, indicating some deviation from perfect constancy. Red filters resulted in more color chips appearing red, blue and green filters resulted in more chips appearing blue, and filters along the Planckian locus resulted in more chips appearing green.

Adult↗

PubMed2006

Combining color and shape information for illumination-viewpoint invariant object recognition.

In this paper, we propose a new scheme that merges color- and shape-invariant information for object recognition. To obtain robustness against photometric changes, color-invariant derivatives are computed first. Color invariance is an important aspect of any object recognition scheme, as color changes considerably with the variation in illumination, object pose, and camera viewpoint. These color invariant derivatives are then used to obtain similarity invariant shape descriptors. Shape invariance is equally important as, under a change in camera viewpoint and object pose, the shape of a rigid object undergoes a perspective projection on the image plane. Then, the color and shape invariants are combined in a multidimensional color-shape context which is subsequently used as an index. As the indexing scheme makes use of a color-shape invariant context, it provides a high-discriminative information cue robust against varying imaging conditions. The matching function of the color-shape context allows for fast recognition, even in the presence of object occlusion and cluttering. From the experimental results, it is shown that the method recognizes rigid objects with high accuracy in 3-D complex scenes and is robust against changing illumination, camera viewpoint, object pose, and noise.

Algorithms↗

PubMed2007

Selection and fusion of color models for image feature detection.

The choice of a color model is of great importance for many computer vision algorithms (e.g., feature detection, object recognition, and tracking) as the chosen color model induces the equivalence classes to the actual algorithms. As there are many color models available, the inherent difficulty is how to automatically select a single color model or, alternatively, a weighted subset of color models producing the best result for a particular task. The subsequent hurdle is how to obtain a proper fusion scheme for the algorithms so that the results are combined in an optimal setting. To achieve proper color model selection and fusion of feature detection algorithms, in this paper, we propose a method that exploits nonperfect correlation between color models or feature detection algorithms derived from the principles of diversification. As a consequence, a proper balance is obtained between repeatability and distinctiveness. The result is a weighting scheme which yields maximal feature discrimination. The method is verified experimentally for three different image feature detectors. The experimental results show that the fusion method provides feature detection results having a higher discriminative power than the standard weighting scheme. Further, it is experimentally shown that the color model selection scheme provides a proper balance between color invariance (repeatability) and discriminative power (distinctiveness).

Algorithms↗

PubMed2001

Perspective: Evolution of flower color in the desert annual Linanthus parryae: Wright revisited.

Linanthus parryae, a diminutive desert annual with white or blue flowers, has been the focus of a long-standing debate among evolutionary biologists. At issue is whether the flower color polymorphism in this species is the product of random genetic drift, as Sewall Wright argued, or of natural selection, as proposed by Carl Epling and his colleagues. Our long-term studies of three polymorphic populations in the Mojave Desert demonstrate that flower color is subject to selection that varies in both time and space in its direction and magnitude. For all sites taken together, blue-flowered plants produced more seeds than white-flowered plants in years of relatively low seed production, whereas white-flowered plants had higher fitness in years of high seed production. Evidence of selection on flower color was found in two of the three study sites. Differences in fitness between the color morphs were sometimes large, with selection coefficients as high as 0.60 in some years. Our longest period of observations was at Pearblossom site 1, where plants reached appreciable densities in seven of the 11 years of study. Here we found significant differences in the seed production of the color morphs in six years, with three years of blue advantage and three years of white advantage. For all sites taken together, total spring precipitation (March and April) was positively correlated with both absolute and relative seed production of the color morphs. At Pearblossom site 1, blue-flowered plants typically had a fitness advantage in years of low spring precipitation, whereas white-flowered plants had a fitness advantage in years of high spring precipitation. This temporal variation in selection may contribute to the maintenance of the flower-color polymorphism at Pearblossom site 1, whereas gene flow from neighboring populations is proposed as the principal factor maintaining the polymorphism at the other study sites. We found no significant differences between the color morphs in pollinator visitation rate or in their carbon isotope ratio, a measure of water-use efficiency. Although the mechanism of selection remains elusive, our results refute Wright's conclusion that the flower color polymorphism in L. parryae is an example of isolation by distance, a key component of his shifting balance theory of evolution.

Adaptation, Physiological↗

PubMed2006

Skin color of Koreans: statistical evaluation of affecting factors.

BACKGROUND: The L*a*b* three-dimensional coordinate system is the most popular system used to measure skin color. The purpose of this study was to collect standard quantified data on Korean skin color using a chromameter CR-300, and to investigate the relationships among skin color and the general and individual factors that affect it. METHODS: The 600 subjects used in this study were selected using a three-stage proportionate stratified and quota sampling method. We examined the color of 12 body parts of each subject and calculated the E* value (total color difference between two objects). This study also analyzed factors that may affect skin color. RESULTS: The average L*a*b* values for the 12 body parts were 61.7462, 9.5618 and 17.0778, respectively. The site of lightest skin was the medial arm (L=63.9249), whereas the darkest was on the forehead (L=58.0044). Redness was highest on the cheek (a=11.8694) and lowest on the medial arm (a=8.1844). Skin color was lighter and more yellow in females than in males, whereas redness was higher in males. In the case of total color difference between two specific sites, the medial upper arm and forearm were the most similar (E=3.23), and the forehead and medial upper arm were the most different in color (E=7.99). CONCLUSION: The factors that significantly (P<0.01) influenced L* were sex, work place and sunbathing, factors that influenced a* were sex, work place and smoking; and the factors that influenced b* were sunbathing and age.

Asian People↗

PubMed2006

Object color affects identification and repetition priming.

We investigated the influence of color on the identification of both non-studied and studied objects. Participants studied black and white and color photos of common objects and memory was assessed with an identification test. Consistent with our meta-analysis of prior research, we found that objects were easier to identify from color than from black and white photos. We also found substantial priming in all conditions, and study-to-test changes in an object's color reduced the magnitude of priming. Color-specific priming effects were large for color-complex objects, but minimal for color-simple objects. The pattern and magnitude of priming effects was not influenced either by the extent to which an object always appears in the same color (i.e., whether a color is symptomatic of an object) or by the object's origin (natural versus fabricated). We discuss the implications of our findings for theoretical accounts of object perception and repetition priming.

Color Perception↗

PubMed2006

Color vision and macular recovery time in epileptic adolescents treated with valproate and carbamazepine.

Visual dysfunction has been reported in patients diagnosed with epilepsy. Some of these visual disturbances may be attributable to either the disease process, or the anticonvulsant therapy prescribed to control the seizures. The aims of our study were to evaluate whether color vision and macular function are impaired in epileptic adolescents, to study if the monotherapy with valproic acid (VPA) and carbamazepine (CBZ) can affect color vision and macular function and to determine the possible relationship between color vision, retinal function and antiepileptic drugs (AEDs) dosage and their serum concentrations. We examined 45 (16 male and 29 female, mean age +/- SD, 15.71 +/- 2.01 years) Caucasian epileptic patients suffering from various types of cryptogenic epilepsy before the beginning of therapy and after 1 year of VPA or CBZ monotherapy and 40 sex- and age-matched healthy controls. Color vision was assessed by Farnsworth Munsell (FM) 100-hue test and total error score (TES) was evaluated. This test consists of colored caps: the testee has to arrange the caps according to their colors macular function was assessed by nyctometry evaluating initial recovery time (IRT) and summation method (SM). This test evaluates visual acuity after a period of intense illumination of macula. Analysis of variance was used to evaluate the difference between controls and patients; moreover, Pearson's correlation test have been performed. Before the beginning of therapy, there were no differences in color vision and macular function between controls and epileptic patients. After 1 year, the patients, treated with VPA or CBZ, showed a deficit in FM 100-hue test. At nyctometry, all patients showed no significant variation of macular function between baseline evaluation and second evaluation at end of the follow-up. Our study demonstrates that, in our group of epileptic patients, epilepsy per se does not affect color vision and retinal function. In contrast, after 1 years of therapy with VPA and CBZ these patients showed a deficit in FM 100-hue test although nyctometry evaluation continued to be normal allowing to exclude an impairment in macular function. Further investigations are required to determine the pathophysiological alteration(s) that are at the basis of color perception defects.

Adolescent↗

PubMed2005

Necrotizing enterocolitis: assessment of bowel viability with color doppler US.

PURPOSE: To determine whether absence of bowel wall perfusion at color Doppler ultrasonography (US) is indicative of bowel necrosis in neonates with necrotizing enterocolitis (NEC). MATERIALS AND METHODS: This study was approved by the research ethics board, and informed consent was obtained. Sixty-two neonates enrolled in the prospective study underwent US of the bowel wall. Neonates were divided into two groups. Group A included 30 control subjects with gestational ages (GAs) ranging from 24 to 41 weeks. Group B included 32 neonates with GAs ranging from 24 to 40 weeks who were clinically proved to have or suspected of having NEC. All neonates in group B underwent abdominal radiography. Normative values were calculated in group A. In group B, the sensitivities and specificities of color Doppler US and abdominal radiography for detection of bowel necrosis were computed by using the modified Bell staging criteria for NEC as the reference standard. RESULTS: Two neonates were excluded from group B; thus, a total of 60 neonates were included in the study. In group A, bowel wall thickness ranged from 1.1 to 2.6 mm. Bowel wall perfusion was detected with color Doppler US in all 30 neonates. Color Doppler signals ranged from one to nine dots per square centimeter. Twenty-two of 30 neonates in group B received a diagnosis of NEC. Mild to moderate NEC was diagnosed in 12 neonates. Color Doppler US depicted an isolated segment of bowel-absent blood flow in two neonates; this finding was confirmed with laparotomy. In 10 neonates with severe NEC, color Doppler US depicted isolated or multiple segments of bowel with absent perfusion. Pneumoperitoneum was present in only four neonates. The remaining eight neonates at risk for NEC had no evidence of loops without perfusion at color Doppler US. The sensitivity of free air at abdominal radiography as a positive sign for severe NEC with necrotic bowel was 40% compared with the 100% sensitivity of absence of flow at color Doppler US (P = .03). CONCLUSION: Color Doppler US is more accurate than abdominal radiography in depicting bowel necrosis in NEC.

Enterocolitis, Necrotizing↗

PubMed1994

Broad-tuned chromatic inputs to color-selective neurons in the monkey visual cortex.

1. Input mechanisms of 21 color-selective cells in cytochrome oxidase-rich blobs in layer II/III of the anesthetized and paralyzed monkey primary visual cortex were studied by an iontophoretic administration of the GABAergic receptor antagonist bicuculline methiodide (BMI). 2. Color-selective blob cells become responsive to originally nonresponsive colors of stimuli or brightness contrast stimuli during removal of intracortical inhibition. 3. The magnitudes of the cells' responses to color stimuli during BMI administration were larger than the expected value of response calculated from the previously reported color tuning of color-selective geniculate cells and emission spectra of color stimulus. 4. These results suggest that color-selective blob cells receive a convergence of different types of chromatic inputs and that intracortical inhibition confers selectivity for a given color on them.

Animals↗

PubMed1996

Echocardiographic quantification of regional left ventricular wall motion with color kinesis.

BACKGROUND: Color kinesis is a new technology for the echocardiographic assessment of left ventricular wall motion based on acoustic quantification. This technique automatically detects endocardial motion in real time by using integrated backscatter data to identify pixel transitions from blood to tissue during systole on a frame-by-frame basis. In this study, we evaluated the feasibility and accuracy of quantitative segmental analysis of color kinesis images to provide objective evaluation of regional systolic endocardial motion. METHODS AND RESULTS: Two-dimensional echocardiograms were obtained in the short-axis and apical four-chamber views in 20 normal subjects and 40 patients with regional wall motion abnormalities. End-systolic color overlays superimposed on the gray scale images were obtained with color kinesis to color encode left ventricular endocardial motion throughout systole on a frame-by-frame basis. These color-encoded images were divided into segments by use of custom software. In each segment, pixels of different colors were counted and displayed as stacked histograms reflecting the magnitude and timing of regional endocardial excursion. In normal subjects, histograms were found to be highly consistent and reproducible. The patterns of contraction obtained in normal subjects were used as a reference for the objective automated interpretation of regional wall motion abnormalities, defined as deviations from this pattern. The variability in the echocardiographic interpretation of wall motion between two experienced readers was similar to the diagnostic variability between the consensus of the two readers and the automated interpretation. CONCLUSIONS: Color kinesis is a promising new tool that may be used clinically to improve the qualitative and quantitative evaluation of spatial and temporal aspects of global and regional wall motion. In this initial study, segmental analysis of color kinesis images provided accurate, automated, and quantitative diagnosis of regional wall motion abnormalities.

Adult↗

PubMed2005

When blue is larger than red: colors influence numerical cognition in synesthesia.

In synesthesia, certain stimuli ("inducers") may give rise to perceptual experience in additional modalities not normally associated with them ("concurrent"). For example, color-grapheme synesthetes automatically perceive achromatic numbers as colored (e.g., 7 is turquoise). Although synesthetes know when a given color matches the one evoked by a certain number, colors do not automatically give rise to any sort of number experience. The behavioral consequences of synesthesia have been documented using Stroop-like paradigms, usually using color judgments. Owing to the unidirectional nature of the synesthetic experience, little has been done to obtain performance measures that could indicate whether bidirectional cross-activation occurs in synesthesia. Here it is shown that colors do implicitly evoke numerical magnitudes in color-grapheme synesthetes, but not in nonsynesthetic participants. It is proposed that bidirectional coactivation of brain areas is responsible for the links between color and magnitude processing in color-grapheme synesthesia and that unidirectional models of synesthesia might have to be revised.

Adult↗

PubMed2006

Coming unbound: disrupting automatic integration of synesthetic color and graphemes by transcranial magnetic stimulation of the right parietal lobe.

In some individuals, a visually presented letter or number automatically evokes the perception of a specific color, an experience known as color-grapheme synesthesia. It has been suggested that parietal binding mechanisms play a role in the phenomenon. We used a noninvasive stimulation technique, transcranial magnetic stimulation (TMS), to determine whether the posterior parietal lobe is critical for the integration of color and shape in color-grapheme synesthesia, as it appears to be for normal color-shape binding. Using a color-naming task with colored letters that were either congruent or incongruent with the synesthetic photism, we demonstrate that inhibition of the right posterior parietal lobe with repetitive TMS transiently attenuates synesthetic binding. These findings suggest that synesthesia (the induction of color from shape) relies on similar mechanisms as found in normal perception (where the perception of color is induced by wavelength).

Adult↗

PubMed2002

Subjective color from apparent motion.

In an effect we call color from motion (CFM), apparent motion is accompanied by subjective color spread seen in physically achromatic regions. Here we report that physical lights can cancel the subjective color seen in CFM. As measured by cancellation, the saturation of the subjective color spread increases as the luminance of the test elements increase. Without luminance differences between test and surround elements, chromaticity differences alone can result in the perception of subjective color spread. In this case, subjective color spread is seen without seeing a subjective contour, suggesting that CFM does not require contour formation and that color - independent of contour - can be recovered in tandem with seeing motion. There are two modes in which CFM is perceived, either (1) as a localized change of illumination, a colored spotlight or shadow, moving over a textured surface or (2) as a moving, colored object seen through holes in an occluding surface. The mode in which CFM is seen depends on figural cues and on regional differences in luminance contrast between the chromatic elements and the achromatic background. Regions with distinct figural cues are always seen as moving; and CFM is seen in the first mode if the regions are of lower luminance contrast and in the second mode if the regions are of higher luminance contrast. Without figural cues, the regions of lower luminance contrast are always seen to move and CFM is seen in the first mode.

Color Perception↗

PubMed2002

Color opponent neurons in V1: a review and model reconciling results from imaging and single-unit recording.

The signals in visual cortex that ultimately give rise to color perception remain poorly understood. Controversy has particularly surrounded one aspect of color's encoding in the visual system-opponent processing in primary visual cortex. Early single-unit studies suggested that V1 contains relatively few color-opponent neurons. Neuroimaging measurements, however, have suggested that such neurons might be relatively numerous. Here, we reconcile these apparently discrepant results and conclude that V1 contains relatively large numbers of color-opponent neurons. We first review results from each method and find that most neuroimaging studies provide evidence of substantial color opponency in V1, and that despite apparent controversy, most single-unit studies agree that relatively large numbers of V1 neurons show some sort of color opponency. To reconcile the results from different techniques more formally, we used electrophysiological data to predict the outcomes of neuroimaging experiments. We simulated the expected fMRI response in V1 to spatial patterns of different color, based on the neurons' properties, as reported in Johnson, Hawken, and Shapley, (2001). The simulated responses to stimuli used in Engel, Zhang, and Wandell, (1997) agree well with the actually observed fMRI results. The model identifies several factors that led to the apparent discrepancy between techniques, and makes testable predictions about how these factors influence the magnitude of color-opponent signals. fMRI and single-unit data converge to show that large numbers of color-opponent neurons exist in V1.

Color Perception↗

PubMed1982

Color analysis of dental modifying porcelains.

Sintered samples of modifying porcelains of various colors and manufacturers were analyzed using reflectance spectrophotometry. Color designations are reported according to practices of the Commission Internationale de l'Eclairage (International Commission for Illumination), and color names were assigned based on a method developed through a joint effort of the Inter-Society Color Council and the United States National Bureau of Standards (ISCC-NBS). Within samples labeled by the same color, differences among manufacturers were found in the color designations and names. These differences were noted in part by plots of the chromaticity coordinates of the samples. The ISCC-NBS method of designating colors is proposed as a uniform and descriptive color-naming method for modifier porcelain. Consistent color naming is a step in improving communication over the use of modifying porcelains.

Color↗

PubMed2004

An evaluation of UV protection imparted by cotton fabrics dyed with natural colorants.

BACKGROUND: The ultraviolet properties of textiles dyed with synthetic dyes have been widely reported in literature. However, no study has investigated the ultraviolet properties of natural fabrics dyed with natural colorants. This study reports the Ultraviolet Protection Factor (UPF) of cotton fabrics dyed with colorants of plant and insect origins. METHODS: Three cotton fabrics were dyed with three natural colorants. Fabrics were characterized with respect to fabric construction, weight, thickness and thread count. Influence of fabric characteristics on Ultraviolet Protection Factor was studied. Role of colorant concentration on the ultraviolet protection factor was examined via color strength analysis. RESULTS: A positive correlation was observed between the weight of the fabric and their UPF values. Similarly, thicker fabrics offered more protection from ultraviolet rays. Thread count appears to negatively correlate with UPF. Dyeing with natural colorants dramatically increased the protective abilities of all three fabric constructions. Additionally, within the same fabric type UPF values increased with higher depths of shade. CONCLUSION: Dyeing cotton fabrics with natural colorants increases the ultraviolet protective abilities of the fabrics and can be considered as an effective protection against ultraviolet rays. The UPF is further enhanced with colorant of dark hues and with high concentration of the colorant in the fabric.

Animals↗

PubMedDate not supplied

Skin discoloration with blue food coloring.

OBJECTIVE: To describe a pediatric patient who developed a clinical cyanotic appearance after receiving an excessive amount of blue food coloring. CASE SUMMARY: An 11-year-old white girl with cerebral palsy was admitted for unresolving aspiration pneumonia and dehydration. Antibiotics and intravenous fluids were administered. During the hospital course, enteral nutrition containing blue food coloring was also administered. Twelve hours after the start of enteral nutrition, the patient appeared cyanotic despite a regular respiratory rate and normal oxygen saturation. The pediatric code response team was called. Enteral nutrition was stopped and then restarted without blue food coloring. Over the next 24 hours, the cyanotic appearance resolved and no further complications developed. DISCUSSION: At our institution, blue food coloring is used with enteral nutrition for detecting aspiration of stomach contents. The dietary department supplies food coloring to each nursing unit in pint-sized medicine bottles. Nurses place an unstandardized amount of blue food coloring into each enteral nutrition bag. This child received an unspecified amount of FD&C Blue No. 1 food coloring. No toxicity studies exist for acute or human ingestion, but the National Academy of Sciences lists 363 mg/d of FD&C Blue No. 1 as a safe level for humans. We estimated this child ingested 780-3,940 mg of dye over a 12-hour period. CONCLUSIONS: This is the first known report of an adverse effect from blue food coloring. To prevent similar occurrences within our institution, the blue food coloring for tube feedings will be dispensed by the pharmacy department in standardized units.

Child↗