bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of coronary angiography on residual renal function in patients on peritoneal dialysis
Authors: Weisbord Steven D. , Bernardini J Udith , Mor Maria K. , Harrwig Kathryn C. , Nicoletta Patricia J. , Palevsky Paul M. , Piraino B Eth 
Published: June 2007

AbstractBackground: The risk of intravascular radiocontrast to residual renal function (RRF) in patients on peritoneal dialysis (PD) remains largely unknown.Hypothesis: This study sought to estimate the effect of coronary angiography on RRF in patients on PD.Methods: All patients at the VA Pittsburgh Healthcare System and University of Pittsburgh who underwent coronary angiography between 1993 and 2005 while on PD and who had RRF measured prior to angiography were identified retrospectively. For patients without a postprocedure RRF recorded, medical records were reviewed to determine whether anuria had developed. The longer‐term rate of loss of RRF among cases was compared with a composite rate of decline in RRF among cases before angiography and matched controls.Results: Twenty‐nine patients with a mean preprocedure RRF of 4.4 ±3.2 ml/min/1.73m2 were evaluated. Of these patients, 23 (79%) had postangiography RRF assessments (mean clearance 3.4 ± 3.0 ml/min/1.73m2). One of the remaining six patients definitely became permanently anuric following angiography, one was lost to follow‐up, and there was no postprocedure RRF assessment in four others. The rate of decline in RRF in the cases was similar to the composite rate (0.07 ml/min/1.73m2/month vs. 0.09 ml/min/1.73m2/month, p = 0.53)Conclusion: The risk for permanent anuria in patients on PD undergoing coronary angiography appears to be quite small. Patients who do not develop anuria following coronary angiography have the same gradual rate of loss of RRF as other patients on PD. Providers should be vigilant in protecting RRF in patients on PD undergoing coronary angiography.
Ultrastructural analysis of the aberrant axoneme morphogenesis in thrips (Thysanoptera, Insecta)
Authors: Paccagnini Eugenio , Mencarelli Caterina , Mercati David , Afzelius Björn A. , Dallai Romano 
Published: June 2007

AbstractThrips spermiogenesis is characterized by unusual features in the differentiating spermatid cells. Three centrioles from which three individual short flagella are initially assembled, make the early spermatid a tri‐flagellated cell. Successively, during spermatid maturation, the three basal bodies maintain a position close to the most anterior end of the elongating nucleus, so that the three axonemes are progressively incorporated in the spermatid cytoplasm, where they run in parallel to the main nuclear axis. Finally, the three axonemes amalgamate to form a microtubular bundle. The process starts with the formation of rifts at three specific points in each axonemal circumference, corresponding to sites 1,3,7 and leads to the formation of 9 microtubular rows of different length, i.e. 3 “dyads”, 3 “triads” and 3 “tetrads”. In the spermatozoon, the nucleus, the mitochondrion and the bundle of microtubules are arranged in a helicoidal pattern. The elongation of the spermatozoon is allowed by the deep anchorage of the spermatid to the cyst cell through a dense mass of material which, at the end of spermiogenesis, becomes a long anterior cylindrical structure. This bizarre “axoneme” does not show any trace of progressive movement but it is able to beat. According to the presence of dynein arms, sliding can take place only within each row and not between the rows. The possible molecular basis underlying the peculiar instability of thrips axonemes is discussed in light of the present knowledge on the organization of the axoneme in mutant organisms carrying alterations of the tubulin molecule. Cell Motil. Cytoskeleton 2007. © 2007 Wiley‐Liss, Inc.
Prognostic value of circulating chromogranin A and soluble tumor necrosis factor receptors in advanced nonsmall cell lung cancer
Authors: Gregorc Vanesa , Spreafico Anna , Floriani Irene , Colombo Barbara , Ludovini Vienna , Pistola Lorenza , Bellezza Guido , Viganò Maria Grazia , Villa Eugenio , Corti Angelo 
Published: June 2007

AbstractBACKGROUND.Increased levels of chromogranin A (CgA), a protein secreted by many neuroendocrine cells, have been detected in sera of patients with neuroendocrine tumors or renal, hepatic, or heart failure. In patients with heart failure, serum CgA correlates with tumor necrosis factor‐α (TNF) and soluble TNF receptors (sTNF‐Rs), with important prognostic implications. The prognostic value of CgA and sTNF‐Rs was investigated in advanced nonsmall cell lung cancer (NSCLC), a histologically heterogeneous group of tumors that may undergo neuroendocrine differentiation.METHODS.CgA and sTNF‐Rs were analyzed in the sera of 88 patients with NSCLC before chemotherapy by enzyme‐linked immunoadsorbent assay (ELISA) and in tumors by immunohistochemistry.RESULTS.Thirteen percent of patients had CgA values greater than the highest value observed in normal subjects (distribution range, 9–724 ng/mL and 28–196 ng/mL, respectively). Immunohistochemical studies showed no correlation between CgA expression in tumors and serum levels. Conversely, circulating CgA was associated with worse Eastern Cooperative Oncology Group (ECOG) performance status (PS) (P = .0005), more advanced stage (P = .042), and survival, with CgA being an independent prognostic factor of poor outcome (hazards ratio [HR] 1.31 for 100 ng/mL increase; 95% confidence interval [95% CI], 1.08–1.60 [P = .0071]). sTNF‐R1 and sTNF‐R2 were also associated with ECOG PS (P = .0001 and P = .02, respectively). sTNF‐Rs was weakly correlated with circulating CgA (r = 0.39 for TNF‐R1 and r = 0.40 for TNF‐R2), suggesting a regulatory link between sTNF‐Rs and CgA secretion.CONCLUSIONS.Increased serum levels of CgA in NSCLC are independent from protein expression in tumors and more likely related to neuroendocrine response associated with worsening of patient condition. In addition to ECOG PS and stage, CgA is an independent indicator of poor prognosis. Cancer 2007. © 2007 American Cancer Society.
Location of the Nodes of Metameric Color Stimuli
Authors: Ohta Noboru , Wyszecki Gunter 
Published: June 2007

AbstractTwo metameric color stimuli have spectral‐power‐distribution curves which, in general, intersect at three or more wavelengths within the visible spectrum. One of these wavelengths is located in the short‐wavelength region, one in the middle‐wavelength region, and one in the long‐wavelength region. Recent work by Thornton puts these wavelengths at 448 ± 4 nm, 537 ± 3 nm, and 612 ± 8 nm, respectively. The rather precise locations of these nodes are examined in this paper. The method of generating metameric color stimuli is found to have a strong influence on the location as well as the frequency of occurrence of the nodes. Different methods will give different locations and frequency distributions, making it difficult to put much significance on Thornton's results.
Concept of correlated color temperature
Authors: Grum F. , Saunders S. B. , Macadam D. L. 
Published: June 2007

AbstractThe concept of color temperature has been used for many years to characterize the relative spectral distribution of energy from light sources. Since not all sources of light are blackbody radiators, the term “correlated color temperature” was devised to indicate the temperature of the blackbody with chromaticity nearest that of the source. Since the CIE has recently recommended two additional color spaces superseding the existing universally agreed system, it is important to know what effect the new recommendation will have on the correlated color temperature determination. In view of this, it has seemed appropriate to design and carry out some fundamental studies in acceptable color matching among color‐normal observers. The isotemperature lines derived from the experimental data described here are within one standard deviation of the isotemperature lines derived from the 1960 UCS diagram. Hence, there is no need to revise the isotemperature lines derived formerly.
A strategy for automatic television colur‐balance correction involving a floating white
Authors: Pearson D. E. , Ray A. K. 
Published: June 2007

AbstractExperimental comparisons are reported of sensor‐derived and picture‐derived techniques for automatic colurbalance correction in colour television. Neither technique was found to ensure point mapping of scene neutrals into display neutrals at 6500 K in all circumstances. An alternative floating‐white system was investigated; quality ratings of this system showed that it performed well over a central range of colour temperatures. The results suggest that fully automatic correctors might beneficially follow a strategy of allowing the system white to float over a limited central range, applying correction graducally outside this range.
Global Color Metrics and Color‐Appearance Systems
Authors: Indow Tarow 
Published: June 2007

AbstractThe Munsell Color System, the color‐appearance system most widely used, has been constructed primarily on the basis of local perceptual uniformity. However, when it is used as a criteron for a uniform chromaticity scale, its global structure is important as well, and this structure is examined in three ways. First, the coordinates H, V, C are shown to function as a conceptual framework in identifying colors. Second, a summary of 12 studies by multidimensional scaling methods based on large color differences is given. It shows that the main part of the Munsell space is approximately Euclidean. Third, a new method based on estimation of principal hue components in each color, 120 in an experiment, yields the same result. Chromatic response functions as in opponent‐color theories are obtained with object colors by this method. In all the results with Japanese observers, 5PB and 5B appear to be too close and both deviate toward 5G compared with the Munsell notation. Whether the finding is due to the observers is discussed.
Colorimetry of Wines
Authors: Little Angela C. 
Published: June 2007

AbstractProblems relating to the measurement and description of color of wines are discussed, with wines providing an example of problems of volume color specification in general. The limitations of conventional directional spectrophotometric transmittance measurements are considered for colloidal, minimally light‐scattering systems, where errors due to light lost through scatter can have profound consequences, particularly at shorter wavelengths. An alternative approach, referred to as transreflectometry, avoids the errors attributable to the directional geometry of conventional spectrophotometers. A review of its application to the colorimetry of wines considers three cases with different requirements to be met and different questions to be answered, from meeting strigent Federal Regulations in the case of very light white wines, to blending red and rosé wines to predetermined color requirements, to studying the kinetics of pigment degradation and colored polymer formation in red wines under controlled storage conditions. These studies demonstrate the versatility of a simple methodological approach which provides information relating to visually perceived color and at the same time to chemical and physical properties of the systems.
Absolute Identification of Colors in the Munsell Notation: Trainability and Systematic Shifts
Authors: Indow Tarow , Watanabe Mariko 
Published: June 2007

AbstractSubjects were asked to identify colors in the Munsell notation, without comparing with the samples of the Munsell Book of Color, and then were immediately told the values of H, V, and C. This training was carried out with 520 colors identified twice by each of five subjects, two experienced and three completely naive with the Munsell system. The effect of training was noticeable over the series of 1040 estimations, and the means of absolute deviations at the end were 3.1, 0.5, and 1.25 for H, V, and C, respectively. Systematic shifts of mean estimations from the Munsell notations were noted: saturated colors tend to be judged lighter when V < 5, there is a tendency to scale compression in the estimation of C, and colors of hue between 7.5B and 7.5B tend to shift toward B, and colors of 10PB and 2.5P, toward P.
The coloroid color system
Authors: Nemcsics Antal 
Published: June 2007

AbstractDeveloped over two decades at the Technical University, Budapest, the Coloroid color system is an aesthetically uniform system, in which scales of hue, saturation, and lightness appear to change uniformly over their entire length, when viewed as a whole. This is not the same as perceptually uniform in the sense of even intervals of small color differences. This article discusses the concepts and derivation of the Coloroid system, relates it to the Munsell and Ostwald systems, and derives the relations of its coordinates to those of the CIE XYZ system.
CIELAB Hue‐Angle Anomalies at Low Tristimulus Ratios
Authors: McLaren K. 
Published: June 2007

AbstractHue angles calculated using the CIELAB recommendation are usually dependent on the luminance factors of the stimulus if any tristimulus ratio is below the critical figure at which the Pauli linear function is applied. This can cause errors of up to 35° in the case of stimuli of low luminance lying on the spectrum locus or purple line. Errorrs are unlikely to occur in the case of surface colors, but in the case of transparent object colors their frequency and magnitude are such as to make CIELAB unsuitable as a color space or as a color‐difference formula whenever a tristimulus ratio is below the critical figure. Practical considerations suggest that in such cases the best solution is to use a modified Judd polynomial function, and this course is suggested for consideration by the CIE Colorimetry Committee and the committee responsible for developing an ISO Standard for the color measurement of plastics.
On exponents of a nonlinear model of chromatic adaptation
Authors: Nayatani Yoshinobu , Takahama Kotaro , Sobagaki Hiroaki , Hirono Junzo 
Published: June 2007

AbstractExponents to be used in a nonlinear model for chromatic adaptation by Nayatani, Takahama, and Sobagaki are discussed and determined as functions of the effective adapting levels by considering several experimental facts of color perception related to a change of adapting illuminance. The analyzed data refer to the color‐appearance attribute “colorfulness” studied by Hunt, the color appearance of a high‐reflectance sample studied by Hunt, the brightness studied by Stevens, and the chromatic adaptation effect between daylight and tungsten light studied by Breneman. By using the derived functions of the exponents it is shown that the model predicts quite well the following perceptual effects: (1) the chromatic adaptation effect between standard Illuminants D65 and A, (2) the dependence of effect (1) on the adapting luminance, (3) the increase of colorfulness of colored samples (the first Hunt effect), (4) the increase of blueness of high‐reflectance samples (the second Hunt effect), (5) the increase of bright and dark contrast of nonselective samples (the Stevens effect), and (6) the color perception of nonselective samples under a colored adapting illumination (the Helson effect). Effects (3)–(5) are observed by increasing the adapting luminance.
A better colorimetric standard observer for color‐vision studies: The stiles and burch 2° color‐matching functions
Authors: Estévez Oscar 
Published: June 2007

AbstractThe validity of the 1931 CIE Standard Observer color‐matching functions (c.m.f.) rests on the assumption that Vλ is a linear combination of actually measured c.m.f. It is shown here that no combination of c.m.f. can reproduce any photometric function. For research on basic questions of color vision it is suggested that the c.m.f. of the Stiles and Burch 2° preliminary study be used. These c.m.f. are reproduced here, after correction and renormalization for a calibration error in the original study. Since photometry appears to be intrinsically more complicated and less well understood than basic colorimetry, it is also suggested the two disciplines be considered as separate aspects of the visual process.
The estimation of cone spectral sensitivities
Authors: MacLeod Donald I. A. 
Published: June 2007

AbstractMethods for estimating the cone spectral sensitivities are reviewed (selectively). Techniques applied to the normal eye include measurement of flicker photometric sensitivity against colored backgrounds; creation of temporary artificial dichromacy by colored bleaches; observations of the afterimages of colored bleaching lights; and transient photopic saturation by flashed backgrounds. Results from these techniques agree well with cone sensitivities estimated from studies of congenital dichromats, and these estimates are further supported by appropriately comparing normal with anomalous trichromatic matches. The indicated sensitivities for red‐ and green‐sensitive cones peak at 566 and 543 nm, respectively. Factor analysis of color‐matching functions indicates normal variation of the order of 1–1.5‐nm standard deviation.
Differences of unique‐ yellow loci between individuals
Authors: Akita Munehira , Ejima Yoshimichi , Takahashi Shigeko 
Published: June 2007

AbstractIn a previous study we noted that a female observer, T, who was diagnosed as a normal trichromat, gave about 536 nm for her unique yellow, which was usually perceived as either green or yellowish‐green by other normal observers. To explore further these individual differences we conducted several preliminary experiments. When we assumed a less sensitive green function for T, who showed no sign of color anomalies with several kinds of color‐blindness tests, we showed that we could interpret the individual differences depicted in three kinds of measures of unique‐yellow loci, namely with colored background, in relative strength of r to g in the context of the opponentcolor theory, and by matching wavelengths to colored papers. One might think of the unique‐hue‐determination technique as being a new sensitive and simple way to investigate color mechanisms, for both normal and abnormal color vision.
Nonlinear nature of the opponent‐color channels
Authors: Yaguchi Hirohisa , Ikeda Mitsuo 
Published: June 2007

AbstractHeterochromatic brightness matches were made between bichromatic mixtures of Λ1 and Λ2, and a 100‐trolands white reference light of 2° visual angle. A remarkable brightness reduction was found in the bichromatic mixtures, showing brightness additivity failure. The failure was especially large at the luminance ratio where hue cancellation occurred. The results were explained by assuming the brightness sensation to be mediated not only by the luminance channel but also by the red‐green and yellow‐blue opponent‐color channels, and by assuming further nonlinear transformation of responses in the opponent‐color channels.
The transformation from cone to channel sensitivities
Authors: Ingling Carl R. 
Published: June 2007

AbstractZone theories of color vision transform R, G, B cone signals to a set of summing and differencing channels. Although the general principles of this transformation are well known, there are subtleties in the transformation which are not well understood. For example: (i) The r–g channel sends two kinds of signal, depending on the spatial frequencies of the stimulus. It sends a difference or hue signal at low spatial frequencies and an additive or achromatic signal in response to high spatial frequencies. (ii) The B‐cone contribution to the r–g channel is greater by a factor of 10 for desaturated stimuli. A quantitative saturation‐dependent mechanism can account for the B‐cone input to the r–g channel.
CIE activities in the measurement of retroreflection
Authors: Moerman Jan J. B. 
Published: June 2007

AbstractFollowing a description of a forthcoming CIE technical report, a general view is given of the parameters which are important in the photometry of retroreflectors and retro‐reflective materials, and of the errors which may occur in their measurement. The goniometer mechanism embodying the new CIE angular system for specifying and measuring retroreflectors is described. Attention is paid to the methods of calibration in determining the coefficient of luminous intensity. The photometry of retroreflective road markings is mentioned, and finally the measurement of the daytime and nighttime colour is dealt with.
Interior and exterior daylight illuminants for the colorimetry of fluorescent materials
Authors: Clarke F. J. J. , McKinnon Rona A. 
Published: June 2007

AbstractThe difficulties in simulating CIE Standard Illuminant D65 are considered and an interior daylight illuminant is described, Illuminant ID65, representing exterior daylight attenuated by average window glass. The benefits of Illuminant ID65 are that it represents the daylight source which most commonly occurs in the viewing of critically coloured merchandise, and that it can be practically simulated using a filtered tungsten‐halogen source. Its applicability to measurements, particularly to the assessment of fluorescent samples, is considered. The results of measurements on the two common classes of fluorescent samples are discussed and indicate that an Illuminant ID65 simulator can be used validly for the measurement of fluorescent materials, even including materials intended specifically for exterior use.
Subjective evaluation of uniform color spaces used for color‐rendering specification
Authors: Mori Leo , Fuchida Takayoshi 
Published: June 2007

AbstractThree attributes of color appearance of sixteen samples illuminated by various light sources were estimated directly by two observers. The results are plotted on a subjective chroma diagram, with which the psychometricchroma diagrams calculated from the CIELUV and CIELAB spaces are compared. The comparison and numerical evaluations show that the CIELAB space is much better than the CIELUV and U* V* W* spaces in simulating surface‐color appearance under various illuminants. Substitution of the CIELAB space for the U* V* W* space used in the CIE method of color‐rendering specification is proposed.
Applying the CIE retroreflectance geometry
Authors: Venable William H. 
Published: June 2007

AbstractAs one of its major efforts during the past three years, the Retroreflectance Subcommittee of CIE Technical Committee 2.3 has defined a system of geometrical coordinates to be used for working with retroreflection. This coordinate system, along with an associated set of defined terms, is intended to provide a common language for describing and specifying the performance of retroreflecting materials and objects.
Truncation error in colorimetric computations
Authors: Krystek W. Erb M. 
Published: June 2007

AbstractThe wavelength interval 360‐830 nm relevant in colorimetric computations is sometimes truncated by the instrument used to measure the spectral characteristic of a material, or the spectral power distribution of a source, or simply by choice. The (systematic) error resulting from this truncation has been derived. Tables are given for the calculation of the truncation error in each case.
Light‐induced colour changes in dyes and materials
Authors: van Beek H. C. A. 
Published: June 2007

AbstractThe present knowledge of the properties and reactions of photoexcited states of dyes and materials is presented and discussed. It is shown that the most probable result of the absorption of daylight by the majority of coloured products in practical use is the decomposition of the colourless substrate or additives, or their photooxidation. In both reactions, radicals are produced which can convert dyes or coloured pigments into compounds that are colourless or possess a different colour. The conclusions drawn may be useful in the interpretation of anomalous light stabilities of coloured products, and help develop products with improved lightfastness.