Determinations of minimum light thresholds as a function of time in the dark have been made for four color normal, three deuteranopic (or deuteranomalous), and four protanopic (or protanomalous) subjects. Measurements were made with red, reddish orange, yellow, green, violet, and white test lights. Dark adaptation curves for the deuteranopes and deuteranomalous are essentially identical with th...

This week Arikawa et al. find that in the small white butterfly, the sexes actually see the world differently. The authors compared the male and female eyes of Pieris rapae crucivora that are equipped with three classes of photoreceptors sensitive to short-wavelength light. In both sexes, the authors detected mRNAs for three novel opsins, one per type of photoreceptor. Intracellular recordings ...

Cellular identification of color receptors in crayfish compound eyes has been made by selective adaptation at 450 nm and 570 nm, wavelengths near the lambda(max)'s of the two retinular cell classes previously demonstrated. By utilizing earlier evidence, the concentration of lysosome-related bodies (LRB) was used to measure relative light adaptation and thus wavelength sensitivity in 665 retinul...

Response functions used in crop simulation models are usually different for different physiological processes and cultivars, resulting in many unknown coefficients in the response functions. This is the case of African violet (Saintpaulia ionantha Wendl.), where a generalized temperature response for leaf growth and development has not been developed yet. The objective of this study was to deve...

Under the circumstances of experimentation described, the sporangiophores of Phycomyces are found to be most sensitive to stimulation by light in the violet between 400 and 430 mmicro. Toward the red, sensitivity falls to nearly zero near 580 mmicro, while in the near ultra-violet around 370 mmicro, sensitivity is still high. The previous experiments of Blaauw had placed the point of greatest s...

The aim of this study was to determine the effect of violet laser stimulation on three acupuncture points in anesthetized rats and to test the hypothesis that violet laser light can modulate neurovegetative parameters like heart rate (HR), heart rate variability (HRV), and mean arterial blood pressure (MAP). Recordings were performed in 10 male anesthetized rats under three conditions in Beijin...

Photoactivatable fluorescent proteins bring new dimension to the analysis of protein dynamics in the cell. Protein tagged with a photoactivatable label can be visualized and tracked in a spatially and temporally defined manner. Here, we describe a basic rational design strategy to develop monomeric photoactivatable proteins using site-specific mutagenesis of common monomeric red-shifted fluores...

The visible light spectrum is wide, and it can be hypothesized that all the wavelengths between 400-700 nm do not induce the same photobiological effects on pigmentation. We assessed the potential pro-pigmenting effects of two single wavelengths located at both extremities of the visible spectrum: the blue/violet line (λ = 415 nm) and the red line (λ = 630 nm). We made colorimetric, clinical, a...