Search Results
Results 701 - 750 of 1224
< 10 11 12 13 14 15 16 17 18 19 20 >
Sanio M - - 1999
First experimental results from a direct-view display made from bacteriorhodopsin (BR) are presented. A dielectric mirror in direct contact with the photoactive BR layer forms the core of the BR display. The dielectric layer both decreases the light intensity necessary for writing and protects the observer from transmitted laser light. ...
Gimeno O - - 1999
A Spanish type of dry fermented sausage, Chorizo de Pamplona, was manufactured with a mixture of (2.29%) different salts (NaCl, KCl, and CaCl(2)) with an equivalent ionic strength to that of the control manufactured with 2.6% NaCl. The use of this salt mixture affected the texture profile analysis (TPA), giving ...
Gorea A - - 1999
In a texture pair (TP) yielding a vertical or horizontal edge, the local (luminance or color) contrast or the local orientation of the individual textels is traded off with the global strength of the luminance-, color-, or orientation-defined TP edge so as to keep the latter at the detection threshold. ...
Anicho U M - - 1999
BACKGROUND: Paremyd, a mydriatic formulation of 0.25% tropicamide and 1.0% hydroxyamphetamine hydrobromide provides adequate dilation for binocular indirect ophthalmoscopy in young Caucasians. We studied the clinical effectiveness of Paremyd in dilating heavily pigmented eyes by comparing its mydriatic efficacy in Blacks, Asians and Caucasians with light and dark brown irides. ...
Kraft J M - - 1999
Saturation of two sets of stimuli was scaled by 21 color-normal observers (ten younger and 11 older observers, mean ages: 30 and 73 years). Circular fields, 1.2 degrees in diameter, were presented in Maxwellian view as 1.5-s flashes with 3-s interstimulus intervals. Stimuli were mixtures of broadband light [CIE(x, y) ...
Mullen K T - - 1999
We have measured the spatial bandwidths of the bandpass red-green chromatic and luminance mechanisms at four locations in the nasal visual field (0, 10, 20 and 30 degrees) using a method of notch filtered noise masking which effectively removes the artifact of off-frequency looking for our stimuli. Detection thresholds were ...
Kraft J M - - 1999
Color constancy is our ability to perceive constant surface colors despite changes in illumination. Although color constancy has been studied extensively, its mechanisms are still largely unknown. Three classic hypotheses are that constancy is mediated by local adaptation, by adaptation to the spatial mean of the image, or by adaptation ...
Gowdy P D - - 1999
Kelly ((1975) Science, 188, 371-372) showed that a centrally-fixated, contrast-reversing edge has a very different effect on the detection of luminance and red-green flicker. Red-green flicker sensitivity was approximately 3-fold greater for a uniform field than for a 'split' field with the two sides flickering out-of-phase. Just the opposite effects ...
Cocilovo A - - 1999
Light therapy has a long history, dating from ancient Egypt to the contemporary treatment of seasonal affective disorder. In the early half of this century, Dinshah Ghadiali, MD PhD, refined a sophisticated system of color therapy. Influenced by a strong background in mathematics and physics, he determined specific "attributes" of ...
Friedman H S HS Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, MD 21218, - - 1999
Color filling-in is a phenomenon in which the color of an object appears to be filled-in by the color of the surrounding field. We have studied the question of whether monkeys perceive color filling-in with near-foveal stimuli under steady fixation. Two monkeys were trained to fixate steadily and to attend ...
Gómez-Barrena E - - 1999
We studied variations in gold chloride techniques to elicit neural elements within articular samples, after "in toto" staining. These techniques attempt the differentiation of neural and vascular structures. Major changes in differential staining were observed when the gold chloride concentration was empirically modified. After the rest of the technique was ...
Keller L M - - 1998
Published reports on the effects of viewed color on physical strength are compromised by failure to specify each of the three dimensions of the color stimuli used. The present study investigated the relationship between color and grip strength by independently measuring the effects of the three dimensions of color. 80 ...
Khurana B - - 1998
Recent evidence challenges the view that attention acts on the outputs of early filters dedicated to processing motion, color, and orientation. Instead, "proto-objects" specified by shading, depth, direction of lighting, and surface information are thought to provide input to attentional processing. These findings are extended here to the parsing of ...
Giulianini F - - 1998
The post-receptoral mechanisms that mediate detection of stimuli in the (delta L/L, delta M/M) plane of color space were characterized using noise masking. Chromatic masking noises of different chromaticities and spatial configurations were used, and threshold contours for the detection of Gaussian and Gabor tests were measured. The results do ...
Schneider N - - 1998
Color and lightness constancy with respect to changing illumination was studied with three different perceptual tasks: ranking of colored papers according (1) to their lightness and (2) to their chromatic similarity in photopic, mesopic, and scotopic states of adaptation, and (3) recognition of remembered colored papers after changes of illumination ...
Guenther H - - 1998
We explored a number of factors affecting the properties relevant to holographic optical data storage by using a two-color recording scheme in reduced, near-stoichiometric lithium niobate. Two-color, or photon-gated, recording is achieved by use of 852-nm information-carrying beams and 488-nm gating light. Readout at 852 nm is nondestructive, with a ...
Paramei G V - - 1998
Small-field color-naming performance of two protanopes over a 4-log luminance range was impoverished in comparison with that of normal trichromats, and was more strongly affected by changes in luminance. At 200 cd/m2 responses to mid-spectral lights were dominated by 'yellow'; with lowering luminance, 'green' and 'red' were increasingly used. In ...
Collin C A - - 1998
Several luminance-matching methods, such as flicker fusion and the minimum motion technique (MMT), are capable of detecting certain forms of abnormal color vision. We present evidence that the heterochromatic fusion nystagmus (HFN) luminance matching technique can discriminate among normal trichromats, protanopes, and deuteranomals. The HFN luminance matching technique has the ...
Arikawa H - - 1998
OBJECTIVES: The purpose of this study was: (1) to examine the light transmittance characteristics of various shades of light-cured composite resins, and (2) to evaluate the effect of light transmittance characteristics on the color of the resins. METHODS: Eleven shades of two composite resins were used. Specimens with four different ...
Kuriki I - - 1998
We examined the relationship between the ambient illuminant chromaticity and changes in the sensitivity balance of the visual system, using illuminants of various chromaticities. The sensitivity of observers was measured in a room with a variable-chromaticity illuminant. The observer's state of chromatic adaptation was measured with unique-white settings. Our results ...
Pisella L L Institut National de la Santé Et de la Recherche Médicale, Unité 94: Vision et Motricité, Bron, - - 1998
In this study, the use of color and location as stimulus attributes manipulated during a simple action was aimed at comparing how dorsal (location) and ventral (color) features are integrated in action and the timing of their processing. Eighteen subjects were presented with a green dot on a computer screen, ...
Sakamoto Y Y Department of Pathology, Wakayama Medical College, - - 1998
To evaluate the color of cytoplasm stained by Papanicolaou staining quantitatively. Cytoplasm photographed under the same conditions was measured for spectral reflection by colorimetry, and the color of the cytoplasm was shown by the L*a*b* color specification. This method enabled us to specify the color of cytoplasm, which was classified ...
Bergamin O - - 1998
BACKGROUND: This study was carried out to investigate the effect of iris color on the pupillary light reflex (PLR) in normal healthy volunteers. METHODS: Pupil perimetry was performed on 50 healthy volunteers with the Octopus 1-2-3 automated perimeter. Within the 30-deg visual field, 33 test locations were investigated four times. ...
Cavanagh P - - 1998
It is widely held that color and motion are processed by separate parallel pathways in the visual system, but this view is difficult to reconcile with the fact that motion can be detected in equiluminant stimuli that are defined by color alone. To examine the relationship between color and motion, ...
Uchida H - - 1998
STATEMENT OF PROBLEM: The selection of shade of composites for restorative applications may have a significant effect on color degradation through environmental exposure. PURPOSE: This study characterized the color changes in composites as a function of shade through environmental effects such as ultraviolet light exposure. MATERIAL AND METHODS: Five shades ...
Vingrys A J - - 1998
We investigated the nature of color and luminance processes under threshold and suprathreshold conditions in normal trichromatic observers. Detection and discrimination contours as well as threshold-vs-contrast (Tvc) functions were measured in the Derrington-Krauskopf-Lennie (DKL) color space using a masking paradigm. Such contours revealed substantial threshold asymmetries along the three cardinal ...
Sassen K - - 1998
The topical meeting on light and color in the open air was held 9-12 February 1997 in Santa Fe, New Mexico. The series of papers that follows represents the fruition of this meeting, revealing the range of current scientific explorations into the play of light and color in nature.
Douglas R D - - 1998
STATEMENT OF PROBLEM: Application of technology that quantify color and color differences is currently used in esthetic restorative materials research. However, parameters for the size of perceptible and acceptable color differences in metal ceramic crowns have not been determined. PURPOSE: The CIELAB colorimetric system was used to study the relationship ...
Sandusky C L - - 1998
Instrument values were compared to sensory perception of ground breast and thigh meat color. Different patty thicknesses (0.5, 1.5, and 2.0) and background colors (white, pink, green, and gray), previously found to cause differences in instrument-measured color, were used. Sensory descriptive analysis scores for lightness, hue, and chroma were compared ...
Sohmiya T - - 1998
When certain elements in a pattern are replaced by colored lines, a spreading of neon-like color can be seen around the lines. Using a variety of neon displaying patterns, we hypothesize that two conditions are critical to the neon effect. One is the occurrence of illusory contours and another a ...
Woods D L - - 1998
The time required to conjoin stimulus features in high-rate serial presentation tasks was estimated in auditory and visual modalities. In the visual experiment, targets were defined by color, orientation, or the conjunction of color and orientation features. Responses were fastest in color conditions, intermediate in orientation conditions, and slowest in ...
Bednarz James - - 1998
Color kinesis is a new echocardiographic technique that aids in the assessment of global and regional left ventricular performance during either systole or diastole. Color kinesis uses automated border detection technology based on backscatter data to display both the magnitude and timing of endocardial motion in real time. The color ...
Albert M K - - 1998
If the mouths of the pacmen of a Kanizsa square are colored, for example red, then an illusory red transparent square is seen. In many visual theories such 'neon color spreading' is explained by assimilation of chromatic and achromatic color. In this paper the achromatic case was investigated. In a ...
Adams R J - - 1998
Groups of newborn human infants (N = 180) were habituated to large 16 degrees achromatic ("white") lights of varying luminance (0.35 to 1.16 log cd/m2) and then tested for recovery of habituation to 16 degrees green (dominant lambda = 545 nm), yellow (dominant lambda = 585 nm) or red (dominant ...
Cheng F H - - 1998
Colors in a scene change under different illuminants. By adopting models that are used to describe human color constancy, the maximum-spectral-value method is proposed to estimate the illuminant from the maximum distribution of reflected lights in an image. From the experimental results, the proposed method recovers colors well with different ...
Baker C L CL - - 1998
Previous research has demonstrated two categorically distinct mechanisms mediating apparent motion of kinematograms composed of eccentricity-confined, randomly placed Gabor micropatterns: a quasi-linear mechanism operating for high micropattern densities and short time separations, and a nonlinear mechanism operating at low micropattern densities or longer time separations. Here we compare the performance ...
Vimal R L - - 1998
The existence of nonoriented cells but not of sustained orthogonal masking for achromatic stimuli led to an investigation of the spatial-frequency (SF) tuning of sustained nonoriented color units. For this purpose the Red-Green channel was isolated by the minimum flicker and hue cancellation techniques. Chromatic contrast sensitivity functions (CSF's), threshold ...
Flach J M - - 1997
In 3 experiments altitude control was examined as a function of texture type and forward speed. Four texture types were used: grid (rectangular grid with neutral colored cells); dot (small triangles distributed randomly on the ground surface); splay (rows of colored texture parallel to the direction of motion); and depression ...
Webster M A - - 1997
Color perception depends profoundly on adaptation processes that adjust sensitivity in response to the prevailing pattern of stimulation. We examined how color sensitivity and appearance might be influenced by adaptation to the color distributions characteristic of natural images. Color distributions were measured for natural scenes by sampling an array of ...
Polzella D J - - 1997
135 university undergraduates heard 12 preludes from J. S. Bach's Well-tempered Clavier (Vol. 1) while viewing alternating red, yellow, green, and blue colored lights. Their task was to rank-order the lights according to how well they "matched" the music. Preferences for combinations of color and music differed depending on whether ...
Allan L G - - 1997
In the typical induction of the orientation-contingent color aftereffect (CCAE), the stimuli are composed of elements that differ in both color and luminance. Three experiments are reported that show that chromatic contrast between stimulus elements is insufficient for the induction of the orientation-CCAE and that luminance contrast is necessary. These ...
Brown R O - - 1997
BACKGROUND: The perceived color at each point in a visual scene depends on the relationship between light signals from that point, and light signals from surrounding areas of the scene. In the well known phenomenon of simultaneous color contrast, changing the overall brightness or hue of an object's surround induces ...
Kelly A P - - 1997
This article focuses on the aesthetic cutaneous considerations in analyzing and treating the aging face in patients of color. Initially some of the physiologic differences between dark and light pigmented skin are elucidated. Hair conditions that lead to aesthetic unacceptance are discussed as are facial enhancing cosmetic procedures, with special ...
Zaidi Q - - 1997
For a visual system to possess color constancy across varying illumination, chromatic signals from a scene must remain constant at some neural stage. We found that photoreceptor and opponent-color signals from a large sample of natural and man-made objects under one kind of natural daylight were almost perfectly correlated with ...
Winckler J R - - 1997
This paper deals with a luminous electric discharge that forms in the mesospheric region between thundercloud tops and the ionosphere at 90-km altitude. These cloud-ionosphere discharges (CIs), following visual reports dating back to the 19th century, were finally imaged by a low-light TV camera as part of the "SKYFLASH" program ...
Yamasaki K - - 1997
In order to investigate the physical, economical, physiological and psychological aspects regarding ancient lighting, two series of experiment were performed. At first a darkroom (1.3 x 4.5 m, Ht: 2.7 m) was constructed. In experiment I, illuminance and consumption rate of fuel were measured. The Japanese classic candle, plant oil ...
Zehong W - - 1997
PURPOSE: To objectively evaluate the clinical application of color pattern reversal visual evoked potential (CPR-VEP) on primary open angle glaucoma (POAG). METHODS: CPR-VEP and FM 100-hue test were performed in 31 eyes with POAG and 33 normal eyes. Color pattern stimulation was presented by color monitor controlled by computer program. ...
Poenar D P - - 1997
Antireflection filters based on multilayer stacks of dielectric and polysilicon films on monocrystalline silicon combined with charge collection in different (poly)Si layers can be used to realize sensors with a programmable spectral response controlled by weighted summing of the photocurrents detected in the polysilicon and the substrate. Thus, employing both ...
Latanov A V - - 1997
Discrimination of colors was studied using an instrumental learning paradigm in monkeys (Macaque rhesus) and fishes (Carpio cyprinus L.). The confusion matrices composed of probabilities of instrumental responses were treated by factor analysis. The spherical structure of perceptual color space revealed in both animals was similar to that in humans. ...
Allen C D - - 1997
Experiments were conducted to compare the shelf-life of dark-colored and light-colored broiler breast meat. In each of three trials, 100 breast fillets were obtained from a commercial processing plant and subjectively categorized as "dark" or "light". The 100 fillets were then objectively evaluated for C.I.E. color values (lightness, redness, and ...
< 10 11 12 13 14 15 16 17 18 19 20 >