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We report a case of a 60-year-old Asian male who developed radiation retinopathy 23 years after initial radiotherapy for nasopharyngeal carcinoma and was successfully treated with yellow pattern 577-nm micropulse laser. Secondary macular edema and visual acuity improved following a single treatment session with minimal scarring. Yellow pattern micropulse laser is a safe and effective treatment for macular edema secondary to radiation retinopathy. [ABSTRACT FROM AUTHOR]

Arsenic (As) turnover in rice paddy agro-ecosystems has received much attention because As can enter the food chain through its accumulation in rice, thereby affecting human health. Returning straw to soil is a common practice to retain nutrients for soil and crops, but it also cycles As within the rice paddy field ecosystems. However, there is still a lack of detailed understanding of the fate of As in rice straw, and how or to what extent it is recycled back into the soil environment. This study aims to elucidate the relationship between the microstructure of rice straw and the release of As during rice straw decomposition. The microstructure of rice straw was found to comprise both organic and silica (phytolith) components. These two constituents are inter-embedded to form a composite-like structure that contains up to 6.48 mg As Kg−1. The 30-day batch experiments revealed that the biochemical release of As simultaneously depends upon the decomposition of the organic component and the desilicification of the silica component. Accompanying the release of As was the release of other elements such as Fe, Al, P and S. These elements can further interact with As to form less mobile compounds. The introduction of either Trichoderma harzianum or Bacillus velezensis was expected to accelerate the decomposition of rice straw, and enhance the silica dissolution, hence contributing to an increase in the As release. Despite these expectations, our observations showed the opposite effects. Microorganisms presumably have facilitated the change in solution chemistry or the inclusion of As into the newly-formed precipitates. The biochemical decomposition process can reduce straw particle size, while the negatively-charge surface will involve microsized straw particles in the electrostatic interaction, thereby favoring the dispersibility state. Therefore, the co-transport of micro-sized straw particles with As under field conditions should not be neglected. [Display omitted] • Microstructure of rice straw was found to comprise an organic and silica composite. • The composite structure that contains up to 6.48 mg As Kg−1. • Release of As depends upon the destruction of the organic-silica composite. • The release rate of As can be interfered with by microbial activities. • Dispersibility of the microsized straw paticles can increase the mobility of As. [ABSTRACT FROM AUTHOR]