bluuebunny/crossref_metadata_2025 huggingface dataset:
Peripheral levels of matrix metalloproteinase‐9, interleukin‐6, and C‐reactive protein are elevated in patients with acute coronary syndromes: Correlations with serum troponin I
Authors: Manginas Athanassios , Bei Evgenia , Chaidaroglou Antigoni , Degiannis Dimitrios , Koniavitou Katerina , Voudris Vassilis , Pavlides Gregory , Panagiotakos Demosthenis , Cokkinos Dennis V.
Published: June 2007

Background: Acute coronary syndromes (ACS) are characterized by activation of systemic and local inflammatory mediators. The interrelation between these soluble inflammatory markers and their association with markers of myocardial necrosis have not been extensively studied.

Hypothesis: The study was undertaken to evaluate the association of the systemic levels of matrix metalloproteinase‐9 (MMP‐9) and the tissue inhibitor of metalloproteinase‐1 (TIMP‐1), with C‐reactive protein (CRP), interleukin‐6 (IL‐6), and serum troponin‐I in patients admitted with ACS.

Methods: Analysis of serum concentrations of the above inflammatory markers was performed in 53 patients with unstable angina (UA) and in 15 with non‐ST‐segment elevation myocardial infarction (NSTEMI) within 48 h of admission, and 34 patients with stable coronary artery disease.

Results: Compared with patients with stable angina, those with ACS had elevated admission levels of MMP‐9 (p = 0.04), CRP (p< 0.001), and IL‐6 (p = 0.001), but not TIMP‐1 (p = 0.55). Compared with patients with UA, those with NSTEMI also had higher levels of IL‐6 (p< 0.001), CRP (p = 0.002), and MMP‐9 (p = 0.05).

Conclusions: In patients with ACS, the admission levels of inflammatory mediators, including MMP‐9, CRP, and IL‐6 are significantly elevated, specifically in association with serum troponin I. Systemic and local markers of inflammatory activity may be directly associated with myocardial injury.
Combination niacin and statin therapy in primary and secondary prevention of cardiovascular disease
Authors: Levy Deborah R. , Pearson Thomas A.
Published: June 2007

Statin monotherapy may not be sufficient to reach serum lipid goals in many patients, especially in those with combined lipid abnormalities. Statins cause only a modest increase in high‐density lipoprotein cholesterol (HDL)—an established independent protective factor for coronary heart disease (CHD)—and a modest decrease in triglycerides (TG). Niacin is an effective pharmacologic agent for increasing HDL, as well as lowering TG. Used in combination with a statin, niacin provides an option to help patients attain their low‐density lipoprotein cholesterol (LDL‐C) goals, non‐HDL goals, and HDL goals. Based on the National Health and Nutrition Examination Survey, 1999 to 2000, only 12% of the surveyed adult population were under treatment for diagnosed hypercholesterolemia. Furthermore, only 5.4% of the surveyed population had attained goal total cholesterol levels of <5.2 mmol/l (< 200 mg/dl). Combination therapy offers a means to get more people to goal. This paper reviews the impact of lipid‐modifying combination therapy with niacin plus a statin on lipid profile outcomes.
The significance of elevated troponin T in patients with nondialysis‐dependent renal insufficiency: A validation with coronary angiography
Authors: Heitner John F. , Curtis Jeptha P. , Haq Salman A. , Corey G. Ralph , Newby L. Kristin , Jollis James G.
Published: June 2007

Background: Patients with elevated troponin are at high risk of adverse outcomes, future cardiac events, and are more likely to have hemodynamically significant coronary artery stenoses. Elevated troponin T (cTnT) in patients with poor renal function portends a poor prognosis; however, findings of significant coronary artery disease (CAD) by coronary angiography have not been demonstrated in patients with poor renal function and elevated cTnT.

Hypothesis: The purpose of this study was to correlate the angiographic findings of patients with elevated cTnT with respect to renal function in patients with nondialysis‐dependent renal insufficiency.

Methods: We retrospectively identified 342 patients with elevated cTnT who underwent coronary angiography in the setting of acute coronary syndrome. Patients were divided into poor (< 40 ml/min) and normal (> 40 ml/min) renal function by measuring their glomerular filtration rate. Our primary outcome was CAD stenosis, defined as epicardial stenosis ≥ 70%. Secondary outcomes were rates of contrast nephropathy, initiation of hemodialysis, revascularization, length of stay (LOS), and in‐hospital mortality.

Results: There was no significant difference in the prevalence of CAD between patients who had positive cTnT with poor renal function versus patients with positive cTnT and normal renal function (87.1 vs. 89.7%, p = 0.54). This finding persisted after stratifying by age. Patients with impaired renal function had a higher mortality, longer LOS, and a higher rate contrast nephropathy requiring hemodialysis.

Conclusion: The association between elevated cTnT and significant CAD stenosis does not vary with renal function.
Peripheral edema due to heart disease: Diagnosis and outcome
Authors: Shah Maulik G. , Cho Shaun , Atwood J. Edwin , Heidenreich Paul A.
Published: June 2007

Background: The purpose of this study was to determine whether baseline physical examination and history are useful in identifying patients with cardiac edema as defined by echocardiography, and to compare survival for patients with cardiac and noncardiac causes of edema.

Hypothesis: Physical examination and history data can help to identify patients with edema who have significant cardiac disease.

Methods: We reviewed the medical records of 278 consecutive patients undergoing echocardiography for evaluation of peripheral edema. We classified cardiac edema as the presence of any of the following: left ventricular ejection fraction <45%, systolic pulmonary artery pressure >45 mmHg, reduced right ventricular function, enlarged right ventricle, and a dilated inferior vena cava.

Results: The mean age of the 243 included patients was 67 ±12 years and 92% were male. A cardiac cause of edema was found in 56 (23%). Independent predictors of a cardiac cause of edema included chronic obstructive pulmonary disease (COPD, odds ratio [OR] 1.74, 95% confidence interval [CI] 1.14–2.60) and crackles (OR 1.98, 95% CI 1.26–3.10). The specificity for a cardiac cause of edema was high (91% for COPD, 93% for crackles); however, the sensitivity was quite low (27% for COPD, for 24% crackles). Compared with patients without a cardiac cause of edema, those with a cardiac cause had increased mortality (25 vs. 8% at 2 years, p < 0.01), even after adjustment for other characteristics (hazard ratio 1.55, 95% CI 1.08–2.24).

Conclusions: A cardiac cause of edema is difficult to predict based on history and examination and is associated with high mortality.
Aspirin resistance, an emerging, often overlooked, factor in the management of patients with coronary artery disease
Authors: Makaryus Amgad N.
Published: June 2007

Aspirin is the most widely used medication in patients with cardiovascular disease. It has had a greater effect on patients with cardiovascular disease than any other drug. With the importance of aspirin now known for decades, it is recently becoming clearer that some patients do not derive as great a benefit from this “wonder drug” secondary to their resistance to its effects. Aspirin resistance, its prevalence, its identification, and how to overcome or avert it with other medications then becomes a central topic of discussion as important, if not more so, than the importance of aspirin itself as a cornerstone in the treatment of patients with cardiovascular disease. This review explores the current understanding of the mechanism of aspirin resistance with regard to its prevalence and the magnitude of its clinical significance. It also examines the therapeutic implications of a diagnosis of aspirin resistance.
The cardiovascular patient's perceptions of complementary and alternative medicine
Authors: Krasuski Richard A. , Michaelis Kyle , Eckart Robert E.
Published: June 2007

Background: Complementary and alternative medicine (CAM) use is common among patients with cardiovascular disorders and is generally underrecognized by physicians. The attitudes of these patients regarding these therapies and their perceptions of safety and efficacy have not been well defined.

Methods: A written survey was received from a cohort of outpatients seen at a large outpatient cardiovascular clinic in Texas. Over 75% of patients responded, with more than 90% of returned surveys adequate for analysis.

Results: Of the 210 respondents 113 admitted to CAM use, with Vitamins E and C being the most frequently utilized agents. Women were significantly more likely to take CAM than men (69 vs. 46%, p = 0.002), particularly those taking hormone replacement therapy. Over half of patients surveyed stated their cardiologist was unaware of their use of CAM. Only 15% of patients felt that CAM was more efficacious than their traditional medications, but almost half felt it was significantly safer. A similar number were unaware of any interactions between CAM and their other medications.

Conclusions: Use of CAM is common in cardiology outpatients, and many patients remain unaware of potential health risks. Physicians should routinely question patients about use of CAM and attempt to educate users regarding potential health risks.
Implantable cardiac arrhythmia devices—part I: Pacemakers
Authors: Kusumoto Fred M. , Goldschlager Nora
Published: June 2007

Implantable cardiac devices have become firmly entrenched as important therapeutic tools for a variety of cardiac conditions. The first part of this two‐part review will discuss the contemporary use and follow‐up of pacemakers, while the second part will address the use of implantable cardioverter defibrillators and implantable loop recorders. Pacemakers are the only available treatment for symptomatic bradycardia not due to reversible causes. Large randomized studies have demonstrated a small but statistically significant reduction in atrial fibrillation associated with pacing modes that maintain atrioventricular synchrony. In contrast, pacing mode appears to have a less dramatic effect in patients with atrioventricular block. Cardiac resynchronization with specialized left ventricular leads has been shown to reduce symptoms and improve survival in patients with symptomatic heart failure, systolic dysfunction, and widened QRS complexes. For all patients, careful follow‐up is necessary to ensure optimal therapeutic benefit of pacing systems.
Safety and efficacy with drug‐eluting stent in st‐segment elevation and non‐ST‐segment elevation myocardial infarction
Authors: Park Chang‐Bum , Lee Cheol Whan , Lee Bong‐Ki , Kim Young‐Hak , Hong Myeong‐Ki , Kim Jae‐Joong , Park Seong‐Wook , Park Seung‐Jung
Published: June 2007

Background: Drug‐eluting stents (DES) have been shown to reduce the need for repeat revascularization compared with bare metal stents (BMS). However, there is little information regarding the safety and long‐term efficacy of DES in patients with acute myocardial infarction (AMI).

Hypothesis: The aim of this study was to evaluate the safety and efficacy of DES in patients with AMI.

Methods: Data from 211 consecutive patients with AMI treated with DES were compared with those from 228 consecutive patients with AMI treated with BMS. All patients were treated within 7 days of symptom onset. The incidence of major adverse cardiovascular events ([MACE]: death, reinfarction, and target vessel revascularization) was evaluated at 30 days and 1 year.

Results: Baseline clinical and angiographic characteristics were similar for both stent groups. However, patients who received DES had longer lesion lengths (23.0 ± 12.7 vs. 18.8 ± 10.6 mm, respectively; p<0.001) and smaller reference diameters (2.97 ± 0.52 vs. 3.19 ± 0.63 mm, respectively, p<0.001). At 30 days, the incidence rates of MACE (DES vs. BMS: 2.2 vs. 1.9%, p = 1.000) and stent thrombosis (BMS vs. DES: 0.9 vs. 1.7%; p = 0.434) did not differ significantly between the groups. At 1 year, patients with DES had a lower rate of MACE (BMS vs. DES: 14.0 vs. 6.6%; p = 0.011) primarily due to a lower target vessel revascularization rate (BMS vs. DES: 9.6 vs. 4.8%; p = 0.028).

Conclusions: The DES appear to be superior to the BMS in reducing the risk of MACE in patients with AMI.
Adiponectin produced in coronary circulation regulates coronary flow reserve in nondiabetic patients with angiographically normal coronary arteries
Authors: Date Haruhiko , Imamura Takuroh , Ideguchi Takeshi , Kawagoe Junji , Sumi Takahiro , Masuyama Hiroyuki , Onitsuka Hisamitsu , Ishikawa Tetsunori , Nagoshi Toshiro , Eto Tanenao
Published: June 2007

Background: Epicardial adipose tissue expresses adiponectin protein, and its expression is significantly lower in patients with severe coronary artery disease (CAD) than in those without CAD. Transcoronary adiponectin levels are significantly decreased in nondiabetic but not in diabetic patients with CAD. Adiponectin is also an important adipocytokine that is linked to insulin resistance and reduces coronary microvascular function.

Hypothesis: Adiponectin may play a significant role in the localized coronary circulation. The present study examines the local dynamics of adiponectin in the coronary circulation in nondiabetic individuals with normal coronary arteries and the relationship between adiponectin and coronary microvasculature function.

Methods: We examined 22 consecutive nondiabetic patients whose coronary arteries were angiographically normal. Plasma levels of adiponectin were measured in blood samples that were simultaneously collected from the orifice of the left coronary artery (LCA) and the great cardiac vein (GCV). To evaluate the function of the coronary microcirculation, we measured coronary flow velocity at maximal hyperemia using a Doppler wire. Coronary flow reserve (CFR) was obtained from the ratio of hyperemia to the baseline coronary flow velocity.

Results: Plasma adiponectin levels in the GCV (median 6.95 μg/ml) were significantly higher than those in the LCA (median 6.60 μg/ml, p<0.0005). The difference in plasma adiponectin levels between GCV and LCA significantly correlated with CFR (R = 0.451, p<0.05).

Conclusions: Adiponectin is locally produced in the coronary circulation. This protein may participate in modulating the coronary circulation of nondiabetic patients with angiographically normal coronary arteries.
Coronary arterial revascularization: Past, present, future: Part I—historical trials
Authors: Gupta Anuj , Burke James , Bove Alfred
Published: June 2007

Advances in coronary artery revascularization have been accompanied by clinical trials evaluating these advances. From the Coronary Artery Surgery Study and Bypass Angioplasty Revascularization Investigation to the more recent Arterial Revascularization Therapy Study (ARTS1) and the Medicine, Angioplasty, or Surgery Study (MASS2), these clinical trials provide us with a rationale for the way we conduct clinical practice. This paper reviews the data supporting historical revascularization strategies for our patients, including medical therapy, angioplasty, and bare metal stents. Several recurrent themes emerge. These include a need for increased revascularization in patients who undergo percutaneous treatments, the durability of surgical arterial revascularization, and the importance of medical therapy as the mainstay of treatment. Part II will address newer therapies.
Elevations of troponin in patients with epileptic seizures? What do they mean?
Authors: Parvulescu‐Codrea Simona , Britton Jeffrey W. , Bruce Charles J. , Cascino Gregory D. , Jaffe Allan S.
Published: June 2007

Cardiac troponin concentrations are important sensitive and specific markers for myocardial injury in clinical medicine. Troponin (TnT) elevations have been noted in some series in the setting of acute neurologic disease. We have previously reported that solitary seizures do not evoke elevations in TnT. The importance of this negative finding is exemplified by a patient who arrived at our clinic following a new onset seizure and in whom the cardiac TnT level was observed to rise. Triggered by this observation and by the knowledge that seizures alone would not do this, a subsequent targeted cardiologic workup documented what was believed to be an extension of a previously unrecognized myocardial infarction, with a seizure as its clinical presentation. Elevations of troponin should not be considered to be due to isolated seizures. This case illustrates the importance of having data concerning the response of troponin in various emergency and clinical situations.
Respiratory changes in the pulse‐oximetry waveform associated with pericardial tamponade
Authors: Stone Maj Kenneth E. , Bauch Terry D. , Rubal Bernard J.
Published: June 2007

Background: Timely identification of hemodynamic compromise in patients with acute pericardial effusion and tamponade is critical in patient management. Respiratory variability in pulse‐oximetry waveforms has been correlated with pulsus paradoxus, but has not been reported with cardiac tamponade in adult patients.

Hypothesis: This study describes changes in respiratory variability in pulse‐oximetry waveform pre and post pericardiocentesis in patients with hemodynamically significant pericardial effusions.

Methods: A single‐center, catheterization laboratory hemodynamic database was reviewed for all patients who underwent pericardiocentesis for clinically suspected tamponade and had continuous digital pulse‐oximetry, electrocardiographic, and respiration waveforms recorded during the procedure. Phasic respiratory changes in pulse‐oximetry waveform amplitude (maxima‐minima) were expressed as an expiratory/inspirato‐ry ratio and compared pre and post pericardiocentesis.

Results: The study population consisted of 12 patients (6 men:6 women, age 60 ± 10 years) with pericardial effusion documented by echocardiography on the day of pericardiocentesis. Phasic respiratory variability in the pulse‐oximetry waveform was evident in all patients prior to aspiration (respiratory ratio = 1.9 ± 0.5). Following pericardiocentesis (aspirated volume: 650 ±300 ml), the respiratory ratio decreased in all patients (1.2 ± 0.1, p = 0.001). Receiver operator characteristic curve analysis suggests that pulse‐oximetry respiratory ratios > 1.5 should raise suspicion of hemodynamic compromise in high‐risk populations.

Conclusions: Pulse‐oximetry is a commonly used tool for monitoring critically ill patients. The present study suggests that increased respiratory variability in the pulse‐oximetry waveform should raise suspicion for hemodynamic compromise in patients at risk for pericardial effusion.
Prognostic significance of hemoglobin level in patients with congestive heart failure and normal ejection fraction
Authors: Varadarajan Padmini , Gandhi Siddharth , Sharma Sanjay , Umakanthan Branavan , Pai Ramdas G.
Published: June 2007

Background: Previous studies have shown low hemoglobin (Hb) to have an adverse effect on survival in patients with congestive heart failure (CHF) and reduced left ventricular (LV) ejection fraction (EF); but its effect on survival in patients with CHF and normal EF is not known.

Hypothesis: This study sought to determine whether low Hb has an effect on survival in patients with both CHF and normal EF.

Methods: Detailed chart reviews were performed by medical residents on 2,246 patients (48% with normal EF) with a discharge diagnosis of CHF in a large tertiary care hospital from 1990 to 1999. The CHF diagnosis was validated using the Framingham criteria. Mortality data were obtained from the National Death Index. Survival analysis was performed using Kaplan‐Meier and Cox regression models.

Results: By Kaplan‐Meier analysis, low Hb (< 12 gm/dl) compared with normal hemoglobin was associated with a lower 5‐year survival in patients with CHF and both normal (38 vs. 50%, p = 0.0008) and reduced (35 vs. 48%, p = 0.0009) EF. Using the Cox regression model, low Hb was an independent predictor of mortality after adjusting for age, gender, renal dysfunction, diabetes mellitus, hypertension, and EF in both groups of patients.

Conclusion: Low Hb has an independent adverse effect on survival in patients with CHF and both normal and reduced EF.
Acute improvement of aortic mechanics following hemodialysis in patients with chronic renal failure
Authors: Soubassi Lygeri P. , Tousoulis Dimitris , Antoniades Charalambos , Lambrou Spyros , Aggeli Constantina , Chaniotis Dimitris , Soubassi Sofia , Pitsavos Christos , Stefanadis Christodoulos , Soubassis Pavlos , Toutouzas Pavlos
Published: June 2007

Background: Evidence suggests that distensibility of the aorta is decreased in patients with end‐stage renal failure, while the underlying mechanisms are unclear.

Hypothesis: The purpose of the study was to evaluate the distensibility of the aorta in patients at the end stage of chronic renal failure before and after hemodialysis (HD).

Methods: The diameter of the ascending aorta and distensibility were assessed in 48 patients on HD (31 men, 17 women, aged 45 ± 14 years) and in 27 normal subjects (17 men, 10 women, aged 44 ± 14 years). The diameter of the aorta was evaluated by M‐mode in the parasternal long‐axis view.

Conclusions: Aortic distensibility in patients with end‐stage renal disease is significantly lower than in normal subjects, and it is significantly improved after HD.

Results: Aortic distensibility was significantly lower in patients on HD before HD (1.9 ± 0.7 cm2·dyn−110−6) than in normal control subjects (3.8 ± 1.0 cm2·dyn−1 106, p< 0.0001). After dialysis, it increased to 2.6 ± 1.2 (p < 0.05 compared with baseline, p < 0.001 compared with controls). The change of aortic distensibility correlated with age (R2 = 0.629 p < 0.001) and ultrafiltration volume (R2 = 0.168, p < 0.01).
Proceedings of the Inter‐Society Color Council Technical Conference “Instrumental Colorant Formulation 1976” Williamsburg, Virginia. III Problems of Fluorescence in Colorant Formulation
Authors: Ganz Ernst
Published: June 2007

The presence of fluorescence in samples to be matched and in dyes to be used for matching requires precautions in measurement and in computation. Measurement of conventional reflectance may cause serious errors of formulation. Standard procedures for calculating matches are usually based on the additivity of the K/S values. In contrast, contributions of fluorescence have to be added to the spectral radiance factors. Specifications for a rigorous procedure are presented. Merits and shortcomings of currently used methods are discussed. An approximation making use of negative Kubelka‐Munk coefficients is set forth. It is valid only for applications of a single fluorescent colorant which may be shaded slightly by minor additions of other colorants.
An Analysis of the HATRA Acceptability Data
Authors: Kuehni Rolf G.
Published: June 2007

Data on the acceptability as matches of textile samples determined and published by the Hosiery and Allied Trades Research Association (HATRA) are analyzed by near‐optimal fitting of ellipsoids to the colorimetric data in CIE color space. The resulting ellipsoids are compared to those of similar data published earlier.
The Specification of Colour Appearance. II. Effects of Changes in Viewing Conditions
Authors: Hunt R. W. G.
Published: June 2007

The effects on colour appearance of changes in surround, illuminant colour, absolute luminance level, and field size are considered. Methods are discussed whereby existing formulae can be used or modified, and new formulae devised, to obtain measures that correlate with the colour attributes involved. Examples of the application of such formulae to practical problems in illuminating engineering and in television are considered briefly. (In Part I the basic concepts and terms necessary for the specification of colour were considered.)
Grids for Assessing Colour Appearance
Authors: Pointer M. R. , Ensell J. S. , Bullock L. M.
Published: June 2007

A technique of subjective magnitude estimation has been used to assess a set of pseudosurface colours, each having a luminance equal to half that of its adapting surround. Five observers scaled each of the colours three times in each of two adaptation conditions corresponding to daylight and tungsten light at 120 cd/m2. Loci of constant hue and saturation were derived in u', v' chromaticity space for daylight and tungsten light. These grids enable the appearance of a colour to be specified from a knowledge of its chromaticity coordinates and they enable such effects as colour constancy and colour fidelity to be investigated in terms of perceived colour appearance.
Effect of Subtense and Surround Luminance on the Perception of a Coloured Field
Authors: Troscianko T. S.
Published: June 2007

It is recognized that a coloured field in a dark surround is perceived as having a lower saturation than that same colour viewed in a light surround, but that this effect is diminished in magnitude if the colour forms part of a complex scene. The object of the present study is to show how the desaturating effect of a dark surround varies as (a) the surround is separated from the coloured field by a uniform grey field, and (b) the angular subtense of the chromatic field is reduced. It is shown that both these factors have a significant effect on the perceived saturation, but that the extent of the change depends on the luminance of the chromatic field. There is some indication that the extent of desaturation is dependent on which colour‐difference mechanism is predominantly excited when the coloured area is viewed. Practical applications of the results, particularly with reference to the viewing of photographs, are considered. The variability inherent in the experiment, in which there was no satisfactory control over the observer's state of adaptation, means that the results described in this paper should be regarded as those of a pilot study. Work is currently in progress to further quantify the effects described here.
Correlated Color‐Temperature Calculations in the CIE 1976 Chromaticity Diagram
Authors: Schanda J. , Danyi M.
Published: June 2007

In 1976 the CIE recommended the adoption of two new color spaces: CIELUVand CIELAB. The first of these is only a minor modification of the CIE 1964 color space, and includes a new u'v' chromaticity diagram replacing the 1960 uv diagram. Correlated color temperature can be calculated using the new diagram, leading to somewhat different results than those calculated according to the CIE 1960 uv diagram. This paper shows the differences for the correlated color temperatures of different phases of daylight.
New Equipment for the Measurement of Color‐Matching Functions
Authors: Viénot Françoise
Published: June 2007

This paper describes equipment designed to measure the color‐matching functions of a human observer, together with the results obtained. Its future potentialities are discussed, as well as its limitations, accúracy, and reliability. The results obtained are in close agreement with the CIE 1964 Standard Colorimetric Observer data and will enable a statistical study of individual color‐matching characteristics to be made.
Influence of Spatial Structure of Adaptation Fields on Parafoveal Colour Matches
Authors: Nunn Brian J.
Published: June 2007

An effect is described in which colour matches established under spatially uniform conditions are disturbed by the introduction of spatial modulation in one half of the adaptation field, even though the mean illumination level and spectral composition of the spatially non‐uniform adaptation field was the same as that of the uniform adaptation field. The effect was studied for a range of monochromatic test and adaptation wavelengths, and its variation with adapting intensity and frequency of spatial modulation is examined. The origin of the effect is discussed.
Color stability of artists' vehicles
Authors: Levison Henry W.
Published: June 2007

The change in color of artists' oil paints caused by the vehicle was determined by normal aging and by an accelerated method. Two cycles causing yellowing followed by exposure to normal room illumination were conducted. Color is reported by the ASTM D 1925 Yellowness Index. Tested were linseed and safflower oils and alkyd, damar, and copal resins. Safflower oil and medium‐oil‐length alkyds yellowed the least. If linseed oil is predominant, the rest of the vehicle has little effect.
Colorimetric measurement of retroreflecting materials. II. Daytime conditions
Authors: Asher L. B. , Harrington T. L. , Stephenson H. F.
Published: June 2007

An international intercomparison of the results of chromaticity and photometric measurements on retroreflecting materials was made to assess the accuracy of such measurements with current laboratory techniques. A representative group of 44 samples in six colours, including both enclosed and encapsulated constructions, was circulated to ten laboratories in Europe and the USA for measurement under closely defined conditions simulating nighttime use. A selection of 15 of the samples was also measured under simulated daytime conditions. This paper describes the daytime measurements and complements and earlier paper which gave the nighttime results. The measured chromaticities show a large overall spread covering an appreciable fraction of the chromaticity regions likely to be permitted in specifications. Spectrophotometric methods gave results in closer agreement than tristimulus measurements. Research into improved measuring techniques is needed to reduce the spread between laboratories to an acceptable level.
Long‐term repeatability of color‐measuring instrumentation: Storing numerical standards
Authors: Marcus Robert T.
Published: June 2007

A major problem in the coatings industry is the preparation and maintenance of standards to be used in the shading of colored products. With the introduction of color‐measuring instrumentation interfaced directly to dedicated digital computers, the storing of reflectance data as numerical color standards becomes feasible. For this technique to be practical, the color instrumentation must be stable and repeatable over a long period of time. Long‐term (up to 719 days) repeatability data were obtained for seven Diano Chromascan Colorimeter‐Abridged Spectrophotometers, interfaced to Digital Equipment Corporation PDP/11 computers, by measuring a set of five color‐stable tiles supplied by the instrument manufacturers. Average repeatabilities of below 0.50, 0.25, 0.30, 0.30 and 0.60 FMC‐2 color‐difference units were found for the black, blue, green, yellow, and red tiles which make up the set. Since this is of the same order of magnitude as the uncertainties found for other systems of standards maintenance, the storing of reflectance data for use as numerical standards may be considered as a viable alternative to maintaining physical standards.
Calculating correlated color temperature with a desktop programmable calculator
Authors: Schanda J. , Mészáros M. , Czibula G.
Published: June 2007

The chromaticities of Planckian radiators in an x, y diagram can be approximated with two polynomials coupling x to the inverse temperature and y to x. The correlated color temperature (cct) of a source can be calculated by using these (xP, yP) values and a simple algorithm to find that particular (xP, yP) point that lies nearest to the chromaticity coordinates of the light source, for which the cct is computed. The temperature used in computing the (xP, yP) point with minimum distance from (x1, y1) is the cct of the source. Another simple algorithm can be used to generate the lines with constant cct for any temperature of a Planckian radiator, in the region 2000–50,000 K. Calculations using these algorithms can be performed using small desktop calculators. The computations can be automated if the memory capacity is equal to 20 registers and the program can be written in the length of 200–400 program steps, depending on the program handling possibilities of the calculator.
Relationship between perfumes and colors
Authors: Déribéré Maurice
Published: June 2007

Les sens sont des espèces d'instruments dont il faut apprendre à se servir (Voltaire—Traité de Mètaphysique).

When a stimulus is perceived by the perceptive system coupled with another sense, one is in the presence of a case of synesthesis. But pseudocases of synesthesis may exist, where it is only psychologic or affective relations which provoke or facilitate such exchanges. These have been studied by the author according to relations between vision of colors and olfactive or gustative senses.
Colorimetric and photometric properties of a 2° fundamental observer
Authors: Vos J. J.
Published: June 2007

The availability of tables with standardized data on the properties of a normal visual visual observer has been a great help in scientific communication. For daily practice these data, going back to the 1920s, still suffice. For basic science they show shortocmings, however. The present paper gives new and extended tables which are intended to be complementary to, rather than to compete with, the old CIE tables.
Determining dimensioned values of kubelka–munk scattering and absorption coefficients
Authors: Marcus Robert T.
Published: June 2007

If hiding computations are to be made in conjunction with computer color matching, the Kubelka–Munk absorption and scattering coefficients, K and S, must be dimensioned (absolute) coefficients. Two procedures for calculating the dimensioned coefficients were compared. In the first, the coefficients were calculated directly by two different methods from films applied at incomplete hiding over white and black substrates. In the second, previously calculated dimensioned coefficients for titanium dioxide formed the basis of determining the coefficients for the remaining pigments from films applied at complete hiding. Experimental results showed the second procedure superior to either method of the first procedure, except for determining dimensioned K and S for titanium dioxide.
The chemistry behind the artist's palette
Authors: Orna Mary Virginia
Published: June 2007

The origin of color in organic and inorganic artists' pigments is discussed and, where possible, is related to their physical properties such as lightfastness and brilliance. Included in the discussion are the nature of color, the types of chemical species that exhibit color, and the structural features of these compounds that make them colored. The compounds are categorized according to the structural properties that enable them to absorb visible radiation.
Proposal for an empirical approach to color reproduction
Authors: Rhodes Warren L.
Published: June 2007

This article is a review of conventional approaches to color transformations between originals and reproductions, and it explores new methods and transformations made possible by point‐by‐point scanning. “Color correction” has traditionally been based on colorimetric matching between an original and its reproduction. “Corrections” have been based either on additivity and proportionality laws or on Neugebauer's equations which assume additivity of tristimulus values. These approaches were appropriate because photographic masking and early color scanners had to rely on analog methods. Digital methods were too slow. Digital processing speeds may have increased enough to allow point‐by‐point processing of the 2 X 107 points scanned in an 8 in X 10 in. original. Several workers have proposed transformations which are not colorimetric matches. Their experiments have been constrained by the need for analog processing and by conventional process characteristics. By using point‐by‐point table lookup, any transformation, including spatial as well as colorimetric, is possible. It will be interesting to study color reproduction using this new tool.
Reply to ohta–wyszecki on location of nodes of metameric stimuli
Authors: Thornton W. A.
Published: June 2007

The simplest spectral‐power distributions of lights which match to a human observer intersect in three specific wavelength bands near 448, 537, and 612 nm. Simple lights which match to a detector intersect near the wavelength of peak spectral response of that detector. By analogy, the three specific wavelength bands must mark the peaks of spectral response of the normal human visual system. More complex spectral‐power distributions of matching lights may mask the relation between intersection behavior and visual system response.
Properties of standard materials for reflection
Authors: Erb W. , Budde W.
Published: June 2007

This article gives a short survey of some literature on the calibration, suitability, properties, and use of various materials which are used as standards of reflectance. The classical ultimate reference standard, smoked magnesium oxide, is discussed briefly, and information is given on the properties of materials presently used: BaSO4, Russian opal glasses, ceramic tiles, and Halon.

Halon is a registered trade name of the Allied Chemical Corporation.

The suitability of these materials for use as transfer standards or working standards is discussed.
Changes in color appearance with variations in chromatic adaptation
Authors: Bartleson C. J.
Published: June 2007

Chromatic adaptation has been studied by applying methods of direct scaling to color appearances of invariant stimuli seen under different conditions of adaptation. The influence on color appearance of correlated color temperature of illumination, sample luminance factor, illuminance, and surround induction was studied. Perceived hue [expressed as proportions of unitary hues] varies with color temperature of illumination but not significantly with luminance factor or illuminance for the conditions of these experiments. Colorfulness varies with color temperature and also with luminance factor and illuminance, although relative colorfulness does not change significantly with illuminance. Lightness varies with luminance factor but is essentially independent of color temperature and illuminance over the ranges investigated here. Achromatic and chromatic lightnesses for samples of equal luminance differ in systematic ways that depend upon dominant wavelength and excitation purity. Color appearance data for daylight adaptation are highly correlated with Munsell Renotation specifications. The results may be used to determine corresponding colors for the adaptation conditions studied [equivalent to CIE Illuminants D65, D50, A, and dark adaptation]. They may also be used to determine color appearances under those conditions throughout a color solid. It is anticipated that they will be used as the basis for developing mathematical expressions for predictions of corresponding colors under other illumination conditions as well.
Predicting corresponding colors with changes in adaptation
Authors: Bartleson C. J.
Published: June 2007

A method is proposed for determining chromaticity coordinates of stimuli that elicit the same colors over changes in chromatic adaptation. The method uses equations derived from a recent study of the influence of chromatic adaptation on color appearance. A single set of König‐type fundamental primaries is used, and the “red” and “green” fundamentals are altered by changes in adaptation according to a coefficient rule while, in addition, the “blue” fundamental is modified through a power transform. No ulterior information is required beyond a knowledge of the chromaticities of samples and illuminants. The method agrees well with the experimental data from which it was derived, with predictions from a number of other transformation methods, and with raw data from five independent studies of chromatic adaptation. The method thus offers utility and a reasonable compromise between generality and simplicity on the one hand and accuracy on the other.
Neo‐impressionism: The most scientific of all schools of color in art
Authors: Birren Faber
Published: June 2007

This is an account of French painting immediately before and after the turn of the twentieth century. Here the scientific revelations of such men as Maxwell and Helmholtz, introduced in France by Ogden N. Rood of the United States, played an important role in color expression.
Cube‐Root Color Spaces and Chromatic Adaptation
Authors: Richter Klaus
Published: June 2007

The recommendations of the International Commission on Illumination (CIE) on the CIELUV 1976 and CIELAB 1976 color spaces are discussed. A cube‐root chromaticity diagram (a',b') for CIELAB 1976 is added. A slightly modified cube‐root chromaticity diagram (A',B') is proposed which takes care of the CIE corrections (1978) for saturated yellow and red colors in CIELAB 1976 color space. Important advantages of the corresponding cube‐root color space labeled LABHNU 1977 are shown and compared to the CIELUV 1976 and CIELAB 1976 color spaces. Chromatic adaptation can be described approximately as an equal (cube‐root) chromaticity shift for all test colors defined by the two chromaticities of the adaptation illuminants. These properties are discussed and compared to our own chromatic‐adaptation data and data published by Bartleson (1978). Color‐appearance attributes and differences are studied for CIE standard illuminants D65 and A. The Munsell data and OSA data and the main properties of different experiments of Evans and Swenholt (1968) and Pointer (1974) lead to the LABHNU 1977 color space which is evaluated for chromatic adaptation to different illuminants and is compared to the CIELAB 1976 and CIELUV 1976 color spaces.
Evaluation of Different Color‐Difference Formulae by Means of an Experiment on Color Scaling: Final Report
Authors: Lozano Roberto D.
Published: June 2007

Eleven color‐difference formulae were tested for medium and large color differences in a psychophysical experiment on color scaling. A preliminary report has been published and one more formula has been added since then. A third experiment is included in this report dealing with variations of the field size and background. The results were tested statistically for conformance to three different types of mathematical law (linear, exponential, and potential) and with a few exceptions, linear approximation showed the higher regression coefficient. For color differences as large as 17 ± 11 CIELAB units, this experiment suggests that the CIELAB formula is a good recommendation, but it is no better than the new proposal of Richter or the well‐known cube root and Adams‐Nickerson formulae.
A Color Metric from Opponent‐Color Visual Channels
Authors: Rich Danny C.
Published: June 2007

A Euclidean metric for colorimetric evaluations based on an opponent‐color system was described by Ingling and Tsou. The metric was shown to work well for predicting the results of the standard color‐discrimination experiment. The metric is applied to the surface‐color data of the Munsell collection, the Morley, Munn, and Billmeyer data, and the data from the ISCC Committee on Color Difference Problems.
Color Differences Caused by Dye Weighing Errors
Authors: Stanziola Ralph
Published: June 2007

This is the first in a series of short communications which we believe will be of immediate practical use to industrial colorists in applying color technology to their daily work. The series is edited by Ralph Stanziola, who replaces James G. Davidson as Special Editor for Industrial Applications at this time. Dr. Davidson now becomes a regular member of our Editorial Board.

Readers who wish to contribute ideas for future Industrial Notes are encouraged to contact Mr. Stanziola at the address given next to the Table of Contents—F.W.B.
Calculation of the Spectral Radiance Factors of Luminescent Samples
Authors: Billmeyer Fred W. , Chong Tak‐Fu
Published: June 2007

It is often desirable to calculate the spectral radiance factor (SRF, the sum of the reflected and fluorescent radiances) which a photoluminescent—commonly called a fluorescent—sample would exhibit if it were irradiated by a standard illuminant, such as CIE D65, which is not available as a source for direct measurement. Several methods described in the literature for calculating the desired SRF from measurements made using available sources are tested experimentally using measurements made on commonly available one‐monochromator integrating‐sphere spectrophotometers. The choice of the calculation method is shown to be less important than the closeness of the match of the spectral distribution of irradiance on the sample to that from the standard illuminant. This is influenced by both the selection of the experimental source and the effects of the integrating sphere. With all variables properly controlled, comparison of calculated and directly measured SRFs leads to color differences less than one CIELAB unit.
Three are Not Enough: An INDSCAL Analysis Suggesting that Color Space Has Seven (£1) Dimensions
Authors: Chang J. J. , Carroll J. D.
Published: June 2007

Forty‐five subjects, including color normals, protanomalous, deuteranomalous, protanopes, and deuteranopes, judged dissimilarities of 26 Munsell color chips chosen to span the full color space (i.e., all three parameters—hue, saturation, and lightness—were varied). Each of the 325 pairs of colors was mounted on a standard grey background board. They were presented to subjects in different random orders and were viewed under a Macbeth daylight lamp. For each pair the subject circled a number varying from 0 (for “identical”) to 9 (for “maximally dissimilar”). Fifty data matrices obtained from 45 subjects (5 were from the same subject on different dates and 2 were from another subject) were analyzed by the INDSCAL method. The three‐dimensional solution yielded the “standard” three dimensions (lightness, red‐green, and yellow‐blue) with the classical “color circle” emerging, in a slightly distorted form, in the plane of the second and third dimensions. Seven dimensions seemed necessary to account fully for these data, however. In seven dimensions each of the “standard” dimensions is paired with a “folded” version. Accompanying lightness is a “folded” lightness dimensions, which we have called “lightness contrast.” The light and dark colors are at one end, contrasted with medium colors at the other. Similarly, “folded” red‐green roughly contrasts red and green with blue, yellow, and the greys, while “folded” yellow‐blue contrasts blue and yellow with red, green, and the greys. The seventh dimension, which may be artifactual, was called “split yellow.” It contrasts very brilliant (high Munsell value and chroma) yellow and orange colors with all the other colors. It is speculated that some of these extra dimensions may relate to anomalous receptor processes characteristic of deviant subjects. The INDSCAL subject space enables discrimination among all five subject types. Specifically, one of the “natural planes” (the red‐green versus “folded” yellow‐blue plane) of the seven‐dimensional solution can be divided into contiguous and fairly compact regions, with each subject type occupying a unique region.
Colour‐Rendering Assessment of Ultraviolet Emission in Light Sources
Authors: Henderson S. T. , Halstead Margaret B.
Published: June 2007

A number of different ways for the assessment of the ultraviolet emission of light sources are surveyed. A method of assessment using a set of three hypothetical near‐white fluorescent samples is described in which the sum of the excitation curves for the fluorescent samples has been made to resemble the spectral emission curve of Standard Illuminant D65 when plotted on a quantum scale of ordinates. The chromaticity shift of each fluorescent sample produced when the reference illuminant D65 is replaced by the test illuminant is used to produce a special fluorescent‐rendering index in a manner analogous to that used for colour‐rendering indices. The index is scaled in such a way that values greater than 100 indicate an excess of ultraviolet for the test lamp compared with the reference illuminant. Special fluorescent‐rendering indices are given for a number of real lamps, and they accord reasonably well with the known performance of the lamps.
On the geometry of the OSA uniform color scales committee space
Authors: Billmeyer Fred W.
Published: June 2007

The arrangement in space of the sample points of the OSA Uniform Color Scales system is described and related to the cuboctahedron, a geometric figure often used to describe the system. The closest‐packed arrangement, in which each point has 12 nearest neighbors, is emphasized.