The daily autumn and winter ultraviolet-A (320-400 nm) (UVA) exposures and 6 min UVA irradiance data for a southern hemisphere subtropical site (Toowoomba, Australia, 27.6 degrees S, 151.9 degrees E) are presented. This data is used to quantify the effect of cloud on UVA using an integrated sky camera and radiation system. Additionally, an estimate of the effect of enhanced UVA exposure on huma...

Dietary phenolics may play a protective role in UV-mediated skin pigmentation through their antioxidant and UV-absorbing actions. In this study, we investigated whether genetic silencing of Nrf2, regulating the transcription of antioxidant genes, affected melanogenesis in primary human epidermal melanocytes (HEMn) and B16F10 melanoma cells subjected to UVA (8J/cm(2)) exposure. Then, we explored...

UVA (315-400 nm), which constitutes approximately 95% of the UV irradiation in natural sunlight, represents a major environmental challenge to the skin and is clearly associated with human skin cancer. Here, we show that a low, nonlethal dose of UVA induces dose-dependent cell cycle progression in human HaCaT keratinocytes. We found that UVA induced cyclin D1 accumulation, whereas siRNA knockdo...

In songbirds, nucleus Uvaeformis (Uva) is the sole thalamic input to the telencephalic nucleus HVC (used as a proper name), a sensorimotor structure essential to learned song production that also exhibits state-dependent responses to auditory presentation of the bird's own song (BOS). The role of Uva in influencing HVC auditory activity is unknown. Using in vivo extracellular and intracellular ...

Nanoscale titanium dioxide is an important physical sun-block material and is widely used in sunscreen. In our test, the influences of the particle size and crystal structure on light absorbance were examined. The experiment shows that the absorbance (Abs) of nanoscale titanium dioxide in UV-ray district is much higher than it in visible light district under the same concentration (0.04 g/L). T...

UVA is a major bio-active component in solar irradiation, and is shown to have immunomodulatory and anti-inflammatory effects. The detailed molecular mechanism of UVA action in regard to calcium signaling in mast cells, however, is not fully understood. In this study, it was found that UVA induced ROS formation and cytosolic calcium oscillations in individual rat mast cells. Exogenously added H...

BACKGROUND People tend to feel better after exposure to ultraviolet (UV) radiation. This study was performed to investigate the impact of UVA exposure on psychological and neuroendocrine parameters. METHODS Fifty-three volunteers were separated into 42 individuals who had UVA exposure and 11 individuals who had no UVA exposure. The UVA-exposed volunteers had irradiation sessions six times in ...

A prototype UVA dosimeter that is responsive to the UVA wavelengths only has been developed for measurement of personal exposures. The chemical phenothiazine, cast in thin film form and which is responsive to both the UVA (320400 nm) and UVB (280-320 nm) part of the spectrum was used and filtered with mylar. This combined system responded to the UVA wavelengths only and underwent a change in op...

The risks incurred from increased exposure to UVA II (320-340 nm) (i.e. during sunscreen use and extended outdoor exposure, tanning parlors) are not well understood. Therefore, we explored the effects of UVA II on skin immune responses in humans. After a single local exposure (4 minimum erythemal dose [MED]) using a xenon are lamp filtered with a narrow bandpass filter (335 +/- 5 nm full width ...