A facile and green route to terpene derived acrylate and methacrylate monomers and simple free radical polymerisation to yield new renewable polymers and coatings

We present new acrylic monomers derived directly from abundant naturally available terpenes via a facile, green and catalytic approach. These monomers can be polymerised to create new polymers with a wide range of mechanical properties that positions them ideally for application across the commodity and specialty plastics landscape; from packaging, cosmetic and medical, through to composites and coatings. We demonstrate their utility through formation of novel renewable polymer coatings

Reprogramming the assembly of unmodified DNA with a small molecule

The ability of DNA to store and encode information arises from base pairing of the four-letter nucleobase code to form a double helix. Expanding this DNA ‘alphabet’ by synthetic incorporation of new bases can introduce new functionalities and enable the formation of novel nucleic acid structures. However, reprogramming the self-assembly of existing nucleobases presents an alternative route to expand the structural space and functionality of nucleic acids. Here we report the discovery that a small molecule, cyanuric acid, with three thymine-like faces reprogrammes the assembly of unmodified poly(adenine) (poly(A)) into stable, long and abundant fibres with a unique internal structure. Poly(A) DNA, RNA and peptide nucleic acid all form these assemblies. Our studies are consistent with the association of adenine and cyanuric acid units into a hexameric rosette, which brings together poly(A) triplexes with a subsequent cooperative polymerization. Fundamentally, this study shows that small hydrogen-bonding molecules can be used to induce the assembly of nucleic acids in water, which leads to new structures from inexpensive and readily available materials

Observation of the triplet metastable dtate of shallow donor pairs in AlN crystals with a negative-U behavior: A high-frequency EPR and ENDOR study

Theoretical predictions about the n-type conductivity in nitride semiconductors are discussed in the light of results of a high-frequency EPR an ENDOR study. It is shown that two types of effective-mass-like, shallow donors with a delocalized wave function exist in unintentionally doped AlN. The experiments demonstrate how the transformation from a shallow donor to a deep (DX) center takes place and how the deep DX center can be reconverted into a shallow donor forming a spin triplet and singlet states. © 2008 The American Physical Society

Specific repression of Tax trans-activation by TAR RNA-binding protein TRBP

The human T-cell leukemia virus type 1 (HTLV-1)-encoded Tax protein activates transcription from the long terminal repetition via association with host cellular factors. In this study, we searched for cellular proteins that interact with Tax and modulate its activity by using the yeast two-hybrid system. One of the strongest interactors was found to be identical with TRBP, which was previously shown to bind to the RNA encoded by the Tat response element of human immunodeficiency virus type 1. Interactions are demonstrated with Escherichia coli-expressed proteins in vitro and in mammalian cells, using one- and two-hybrid systems, and with antibodies that coprecipitate Tax and TRBP at physiological TRBP concentrations. Moreover, TRBP, when directed into the cytoplasm, is capable of preventing transport of Tax into the nucleus. A 60-amino-acid polypeptide suffices for binding to Tax. TRBP inhibits activation of transcription by both Tax and GAL4-Tax fusion proteins. Inhibition is specific for Tax and is not seen with the other activators tested. Our data are consistent with the interpretation that TRBP inhibits the interplay of Tax with the transcription machinery or accessory factors.</jats:p