Effect Of Ambient Light Research Articles

Chemically and mechanically resistant carbon dioxide optrode based on a covalently immobilized pH indicator

An optical chemical sensor for dissolved carbon dioxide has been developed whose dynamic range was adjusted to CO 2 partial pressures ranging from 0 to 100 hPa. The change in the pH of a buffer layer, caused by the diffusion of carbon dioxide through a hydrophobic membrane, is indicated by the colour change of a covalently immobilized dye, and monitored through optical fibers. The sensor also incorporates an optical insulation with a resplendent pigment to increase the reflectivity and to reduce adverse effects of straylight and ambient light. Two methods for layer manufacturing (spreading and spin coating) are described. The sensor membrane is fully LED compatible. The optrode shows a promising performance with respect to chemical and mechanical long term stability, reproducibility, and sterilizability.

An initial investigation of bright light and depression: A neuropsychological perspective

The effects of bright and dim light on finger-tapping rate and on focused and nonfocused dichotic listening performance were evaluated in 21 nondepressed and 21 mildly depressed women. Previous research had proposed decreased left hemisphere (LH) activation in clinically depressed subjects, and pilot data projected a selective activating effect of ambient light on the LH. It was expected that those in the depressed group would have lower base rates of finger tapping, with right-hand rates affected most. The effect for groups was not significant. Bright light exposure was expected to increase the right-hand tapping rate in both groups, with a pronounced effect on depressed subjects. Group × effector × context interactions were not significant. Depressed subjects were expected to have a decreased right-ear advantage (REA) for dichotic consonant-vowel combinations; a main effect of groups was nonsignificant, but in the hypothesized direction. The depressed group also found it more difficult, but not reliably so, to focus attention on stimuli entering the right ear. Neither group experienced the predicted increase in REA in the bright light context. However, the expected increase in the depressed group’s ability to shift focus to the right ear was seen. Longer periods of light exposure, male subjects, and clinically significant populations may yield statistically significant results.

111. シャウカステンの散光のカラー化における画像の周辺光の影響について (第 2 報)(第 49 回総会学術大会一般研究発表予稿)

111. シャウカステンの散光のカラー化における画像の周辺光の影響について (第 2 報)(第 49 回総会学術大会一般研究発表予稿)

Some aspects of the use of laser Doppler flow meters for recording tissue blood flow.

Laser Doppler flow meters are used to provide continuous records of blood flow in tissues. An account is given of their principles of operation and of the differences between two of the commercially available instruments: the Periflux model PF3 and the Moor blood flow monitor model MBF3D. The Periflux tended to have higher noise levels and to drift more than the Moor. The principal disadvantage of these instruments is that they cannot be calibrated in absolute units of blood flow. It is suggested that the method of standardization adopted for the Periflux be used with other machines, based on the signal produced by the Brownian motion of a 0.5% suspension of 0.48 micron diameter polystyrene microspheres at 20 degrees C. The signal representing zero flow in a tissue can be obtained by recording with the same light intensity from a stationary reflector. In model systems the instruments are linear with red cell volume fractions up to only 1%, which is below that likely to be encountered in many tissues. The effects of ambient light and the origin of movement artifacts are also considered.

111. シャウカステンの散光のカラー化における画像の周辺光の影響について (第 2 報)(画像工学-1 画像処理)

111. シャウカステンの散光のカラー化における画像の周辺光の影響について (第 2 報)(画像工学-1 画像処理)

159. シャウカステンの散光のカラー化における画像の周辺光の影響について(画像理論-3 視覚評価)

159. シャウカステンの散光のカラー化における画像の周辺光の影響について(画像理論-3 視覚評価)

Multiquantum well structure with an average electron mobility of 4.0×106 cm2/V s

We report a modulation-doped multiquantum well structure which suppresses the usual ambient light effect associated with modulation doping. Ten GaAs quantum wells 300-Å wide are symmetrically modulation doped using Si δ doping at the center of 3600-Å-wide Al0.1Ga0.9As barriers. The low field mobility of each well is 4.0×106 cm/V s at a density of 6.4×1010 cm−2 measured at 0.3 K either in the dark, or during, or after, exposure to light. This mobility is an order of magnitude improvement over previous work on multiwells.

The effects of low level blue ambient lighting and stimulus size on the classification of colours on displays : Kaufmann, R., and O'Neill, M.C. In: Proc 23rd Ann Conf of the Human Factors Assoc of Canada, Ottawa, Ontario, 26–28 Sep 1990. The Association, Mississauga, Ontario, 1990, pp 209–213, 22 refs

The effects of low level blue ambient lighting and stimulus size on the classification of colours on displays : Kaufmann, R., and O'Neill, M.C. In: Proc 23rd Ann Conf of the Human Factors Assoc of Canada, Ottawa, Ontario, 26–28 Sep 1990. The Association, Mississauga, Ontario, 1990, pp 209–213, 22 refs

101. EL 発光パネル上における画像の周辺光の影響について (第 2 報)(装置-3 注入器他)

101. EL 発光パネル上における画像の周辺光の影響について (第 2 報)(装置-3 注入器他)

159. シャウカステンの散光のカラー化における画像の周辺光の影響について(第 20 回秋季学術大会一般研究発表予稿)

159. シャウカステンの散光のカラー化における画像の周辺光の影響について(第 20 回秋季学術大会一般研究発表予稿)

How does the rat (Rattus norvegicus) adjust food -carrying responses to the influences of distance, effort, predatory odor, food size, and food availability?

Foraging animals will behave in such a way that they maximize foraging efficiency while minimizing risk to predation. Using a behavioral paradigm in which laboratory rats (Rattus norvegicus) were provided with food at one end of an elevated beam and a refuge to which they could carry the food at the other end of the beam, we examined the effects of travel distance, travel difficulty, ambient lighting, predation risk, and food size on foraging behavior. Both lengthening travel distance (by increasing beam length) and increasing travel difficulty (by decreasing beam width) decreased food carrying. When plotted as a function of travel time, the effects of the two treatments appeared to be partly different. Decreasing ambient illumination decreased food carrying, although the rats still responded to distance and food size. In contrast, predator’s odor (cat) stopped foraging altogether. When a store of small food pellets was available, the rats ate for prolonged periods in the open, and eating time increased with travel distance; however, when large food pellets were also available, the rats immediately selected and carried them to the refuge. The experiments show that food-carrying behavior in the rat is influenced by a variety of independently acting factors, which include eating time, food size, travel distance, travel risk, illumination, predation, and exposure time. The varied and flexible foraging behavior of the animals is discussed in relation to optimal foraging theory.

450. EL 発光パネル上における画像の周辺光の影響について(第 47 回総会学術大会一般研究発表予稿)

450. EL 発光パネル上における画像の周辺光の影響について(第 47 回総会学術大会一般研究発表予稿)

450. EL 発光パネル上における画像の周辺光の影響について(画像理論-7 観察系)

450. EL 発光パネル上における画像の周辺光の影響について(画像理論-7 観察系)

101. EL 発光パネル上における画像の周辺光の影響について (第 2 報)(第 19 回秋季学術大会一般研究発表予稿)

101. EL 発光パネル上における画像の周辺光の影響について (第 2 報)(第 19 回秋季学術大会一般研究発表予稿)

Effects of low-level red ambient lighting and stimulus size on classification of colours on displays

Electronic display colours must be selected so that they are easily discriminated and recognized under different ambient lighting and symbol size conditions. This study investigated the effects of low-level red ambient lighting and stimulus size on the classification of a wide range of cathode ray tube colours into a set of common colour name categories. Both ambient illumination and stimulus size influenced the naming of colours. Colour naming reliability levels for each of the stimuli were plotted on the CIE diagram to provide a basis for deriving colours that are least likely to be confused under different ambient lighting and stimulus size conditions.

The release of Leu 5-enkephalin-like immunoreactivity from chicken retina is reduced by light in vitro

A superfusion system was established to examine the efflux of endogenous Leu 5-enkephalin-like immunoreactivity (LE-LI) from isolated chicken retinas. Superfusion with buffer containing high concentrations of K + (60 mM KCl) increased the efflux of LE-LI by 96%. This effect was not observed when Co 2+ (4 mM CoCl 2) was present. Exposing the retinas to light decreased the efflux of LE-LI by 59% compared to that observed during superfusion in the dark. No effect of ambient light could be detected in the presence of Co 2+. Upon reverse-phase high-performance liquid chromatography the material released by the retina comigrated with synthetic Leu 5-enkephalin. These results demonstrate that the release of LE-LI from retinal neurons is increased during the dark, and it is concluded that the lighting conditions exert their effects by modifying the state of polarization of the LE-LI amacrine cells and hence the release of LE-LI from these neurons.

Effect of ambient light on electronically displayed medical images as measured by luminance-discrimination thresholds.

The effect of ambient light on linearization of gray scales was studied in two experiments by measuring brightness-discrimination thresholds for stimuli as a function of ambient-light level. The luminance and contrast levels of stimuli were chosen to include typical instances encountered in electronically displayed medical images. Three ambient-light levels were used: 4 and 40 lx, which span the range that we found in well-controlled radiologic reading rooms set up with electronic displays, and 148 lx, which represents the low end of the ambient-light range found in light-box reading rooms. In the first experiment, discriminability of some test stimuli was found to change as ambient light increased. The pattern of results suggests that a single linearization function would be clinically acceptable in a reading room with ambient light ranging from 4 up to, at least, 40 lx. At 148 lx, however, the just-noticeable-difference versus intensity function is different enough to require a gray-scale linearization function other than our standard one, which is based on 4-lx ambient light. We attribute these changes in stimulus discriminability to changes in the displayed image produced by ambient light, not to changes in the visual sensitivity of the observer. In the second experiment, which controlled for the display changes produced by ambient light, we found no change in stimulus discriminability as a function of ambient light.

Age-related differences in the effects of d-amphetamine and illumination on fixed-interval responding of rats.

The effects of d-amphetamine (0.0, 0.4, and 0.8 mg/kg) on fixed-interval responding in light and dark sensory conditions were examined in rats that were 25, 100, and 200-days-old at the beginning of the experiment. In the youngest and oldest groups, the drug increased responding in light more than in dark. The drug increased responding of the middle age group in the light, but decreased operant rates in the dark. These data appear to support the notion that d-amphetamine reduces the effects of ambient light on behavior in rats.

Development of an optical displacement transducer for the measurement of soil surface profiles

The transducer is a fast response opto-electronic displacement monitor with a working range of ±150 mm about a point 600 mm from the sensing head. Although developed for the measurement of soil surface profiles, the transducer will operate on any diffusely reflecting surface. The device collects light from an illuminated spot on the target surface and focuses this on to a position-sensing photodiode, giving an output related to the position of the target. The signal-conditioning circuitry discriminates against the effects of ambient light and compensates for changes in surface reflectivity; a simple technique is included to give an output directly linear with distance. The frequency response is flat up to 40 Hz.

EEG sensitivity to television: Effects of ambient lighting

The effect of ambient lighting on EEG sensitivity to television has been tested in 16 photosensitive epileptic patients. Those who were not sensitive to 50 Hz IPS responded to TV at a viewing distance of 1 m or less and showed a consistent increase of EEG activation by television when the room was brightly lit. Most of those who were sensitive to 50 Hz IPS were also TV-sensitive at viewing distances greater than 1 m and the effect was most marked with lights off. The results are discussed in the context of previous work showing that some patients with TV epilepsy respond to the raster pattern of the screen and some, at greater distance, to 50 Hz flicker.