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[reaction: see text] Irradiation of isoquinolinium hydroxytris(pentafluorophenyl)borate, 1, and phenanthridium hydroxytris(pentafluorophenyl)borate, 2, in either CH2Cl2 or CH3CN resulted in C6F5 transfer to the isoquinolinium and phenanthridium cations, generating 2-methyl-1-(2,3,4,5,6-pentafluorophenyl)-1,2-dihydroisoquinoline, 3, and 2-methyl-1-(2,3,4,5,6-pentafluorophenyl)-1,2-dihydrophenanthridine, 4, respectively. In addition, photogeneration of H2O x B(C6F5)3 resulted from 1. Photogeneration of C6F5-C6F4H from HO-B(C6F5)3(-) and of C6H5-C6F4H from C6H5-B(C6F5)3(-) was discovered.

Abstract:Histological and mycological studies made on the shot-hole borer beetle (Xyleborus fornicat~rs) galleries of tea stems a t different developmer~tal stages showed that there was dense growth and sporulation of Mo~zcrcrosporirrr,, tr~n.brosi~rm on the outer cell layers of the gallery surface, during thc initial stages, when the beetle lives inside the galleries. The fungus fo1~11s intracellular mycelium in the xylem vessels, apparently by gaining entry through the pits. Intercellular mycelium was not observed. I-Iistochemicnl tests showed the presence of tannins and lignins in some xylem and ray parenchyma cells of beetle infested stems. The tannin content was more in beetle infested stems than in healthy stems of both clones, but a significant difference was not observed in the lignin content. More tannin and globular materials, as well as lesser fungal growth were observed in the tea clone TRI 2023 (reported to be the least susceptible to attack by the shot-hole borer beetle) than in the clone TRI 2025 (most susceptible to attaclr by t h e beetle). There is a gradual reduction in growth of M. anrhrosiu~n and beginning of colonization of the old galleries by other fungal species after the beetle vacates the gallery. None of the fungi isolated from the olcler galleries is lcnown to be involved in woocl rotting of tea although the sten1 borer attack generally leacls to wood rotting.

Fluorescence resonance energy transfer (FRET) is a powerful tool used in a wide range of applications due to its high sensitivity and many other advantages. Co-encapsulation of a donor and an acceptor in nanoparticles is a useful strategy to bring the donor-acceptor pair in proximity for FRET. A highly efficient FRET system based on BODIPY-BODIPY (BODIPY:  boron-dipyrromethene) donor-acceptor pair in nanoparticles was synthesized. Nanoparticles were formed by co-encapsulating a green emitting BODIPY derivative (FRET donor, lmax = 501 nm) and a red emitting BODIPY derivative (FRET acceptor, lmax = 601 nm) in an amphiphilic polymer using the precipitation method. Fluorescence measurements of encapsulated BODIPY in water following 501 nm excitation caused a 3.6 fold enhancement of the acceptor BODIPY emission at 601 nm indicating efficient energy transfer between the green emitting donor BODIPY and the red emitting BODIPY acceptor with a 100 nm Stokes shift. The calculated FRET efficiency was 96.5%. Encapsulated BODIPY derivatives were highly stable under our experimental conditions.

While extensive studies of virus capsid assembly in environments mimicking in vivo conditions have led to an understanding of the thermodynamic driving forces at work, applying this knowledge to virus assembly in other solvents than aqueous buffers has not been attempted yet. In this study, Brome mosaic virus (BMV) capsid proteins were shown to preserve their self-assembly abilities in an aprotic polar solvent, dimethyl sulfoxide (DMSO). This facilitated protein cage encapsulation of nanoparticles and dye molecules that favor organic solvents, such as β-NaYF 4 -based upconversion nanoparticles and BODIPY dye. Assembly was found to be robust relative to a surprisingly broad range of DMSO concentrations. Cargos with poor initial stability in aqueous solutions were readily encapsulated at high DMSO concentrations and then transferred to aqueous solvents, where they remained stable and preserved their function for months.