Long-term changes in Al thin-film extreme ultraviolet filters.

Thin-film Al filters are very popular owing to their high transmittance in the wavelength range of 17-67 nm and low transmittance in the visible and near-UV regions; however, they are prone to oxidation. The amorphous layers on the Al surfaces have much smaller transmittance than the bulk Al material; therefore, they strongly influence the total transmittance of the filter. This paper not only provides the transmittance of very old Al filters but also maps the transmittance development of Al filters over two years since their delivery (in 2016) in an uncontrolled atmosphere.

Beyond identity: Understanding the contribution of the 5' nucleotide of the antisense strand to RNAi activity.

In both the pharmaceutical and agricultural fields, RNA-based products have capitalized upon the mechanism of RNA interference for targeted reduction of gene expression to improve phenotypes and traits. Reduction in gene expression by RNAi is the result of a small interfering RNA (siRNA) molecule binding to an ARGONAUTE (AGO) protein and directing the effector complex to a homologous region of a target gene's mRNA. siRNAs properties that govern RNA-AGO association have been studied in detail.

Topically delivered 22 nt siRNAs enhance RNAi silencing of endogenous genes in two species.

22 nt siRNAs applied to leaves induce production of transitive sRNAs for targeted genes and can enhance local silencing. Systemic silencing was only observed for a GFP transgene. RNA interference (RNAi) is a gene silencing mechanism important in regulating gene expression during plant development, response to the environment and defense.

Systemic GFP silencing is associated with high transgene expression in Nicotiana benthamiana.

Gene silencing in plants using topical dsRNA is a new approach that has the potential to be a sustainable component of the agricultural production systems of the future. However, more research is needed to enable this technology as an economical and efficacious supplement to current crop protection practices. Systemic gene silencing is one key enabling aspect.