In recent years, drug-induced photosensitivity as a side effect has been an increasing problem. To examine the effectiveness of broad-spectrum sunscreens in preventing the disease, we quantitatively assessed efficiency of some sunscreens in suppressing the photosensitized reactions with sparfloxacin, a fluoroquinolone antibacterial agent. Some broad-spectrum sunscreens suppressed sparfloxacin-photosensitized formation of strand-breakage in plasmid pBR322 DNA. The present findings suggest that the use of broad-spectrum sunscreens contributes to the prevention of drug-induced photosensitivity. In addition, the suppressive effects showed a linear relation with the effective UV-A quanta absorbed by the tested sunscreens independent of the product types and manufacturers. Therefore, we propose that the indication of UV-A absorption spectrum in addition to PA classification (protection grade of UV-A) as factors for assessing for the ability of sunscreens to prevent drug-induced photosensitivity. An in vitro method to assess quantitatively the effectiveness of broad-spectrum sunscreens in preventing drug-induced photosensitivity was also presented.

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In designing the color of outdoor industrial products such as cars and bridges, the optical balance of its model and background photograph (or each frame of the video sequence) needs to be maintained. To irradiate incident light onto a model, obtaining the accurate luminance, L_C, of the sun and skylight distribution from all azimuths using luminance signal, E_Y, but also video signal, (E_R, E_G, E_B) is important. We propose how to measure skylight luminance distribution promptly with a highly accurate HDR (high dynamic range) according to video signal (E_R, E_G, E_B), whose value is in an appropriate range each other, is guaranteed for different chromaticity of each pixel and luminance signal, E_Y. Our method is unlike traditional HDR targeting the luminance distribution of skylight without considering appropriate range of individual video signal (E_R, E_G, E_B) and excluding intensity of direct sunlight. That is, we use portable ND filters together with a digital camera fitted with a fisheye lens to meet the requirements mentioned above. We propose how to calculate 1) highly accurate luminance, L_C, in an experiment and 2) the whole range of luminance, L_C, of skylight in all azimuths including direct sunlight according to video signal (E_R, E_G, E_B). Then, we display some field experimental results for showing the effectiveness of our method.

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We developed a method for optimizing lighting design using the genetic algorithm. The floor illuminance of a room was obtained by superimposing the distributions that each light source produced. The illuminance distribution of each light source was calculated using the Monte Carlo Simulation and was stored in a database. The desirable illuminance distribution is obtained by selecting the light sources from the database by genetic algorithm. An optimization condition is represented by the fitness function of a genetic algorithm. To obtain a uniform illuminance distribution, we used the standard deviation of the floor illuminance. The standard deviation of the floor illuminance can be used as an index that represents the uniformity of the illuminance distribution. The lighting design in a simple cubic room is shown as an example. The illuminace distribution yielded by the location of the light sources that were selected using this technique was compared with that of evenly-spaced light sources on the ceiling plane. Although the room that we used was simple, the illuminace distribution obtained by using the technique almost corresponded to the target condition. This technique is practical for optimizing the arrangement of light sources inside a room. Moreover, this technique has various applications such as daylighting by choosing and constructing an applicable fitness function.

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A method for performing bi-directional conversion between luminance and brightness images was devised by using a wavelet transform. The method was similar to a contrast profile method, which can be used to analyze the luminance contrast in complex luminance distributions. We found that a brightness image could be obtained from a luminance image by applying a decomposition and reconstruction procedure on an orthogonal mother wavelet. A bi-directional conversion system was developed using a nearly symmetrical orthogonal wavelet, ‘Symlet 6,’ and the practical uses for the system were discussed.

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Wrong:There are some errors of equations at p.455.
Right:There are some errors of equations at p.455. See the revised one here.

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