‘Octupolar’ molecules are of particular interest in the field of nonlinear optics due to their potentially large quadratic nonlinearities. Within this framework, we have designed
organic chromophores ...of
tetrahedral symmetry and investigated their quadratic nonlinearities by performing harmonic light scattering (HLS) experiments in solutions. Issues related to the molecular engineering of the nonlinearity-transparency trade-off have been addressed. As a result, molecules combining significant quadratic hyperpolarizabilities and excellent transparency have been identified.
From a library of DNA fragments associated with Ultrabithorax protein in vivo, we have isolated
nessy, a new Drosophila gene that encodes a putative transmembrane protein conserved in evolution from
...Caenorhabditis elegans, to human. Zygotic expression occurs transiently in mesectodermal cells at gastrulation, proceeds in mesoderm and endoderm lineages during germ band movements and becomes then restricted to anterior and posterior domains in the visceral mesoderm. The Hox proteins Ultrabithorax, Antennapedia and AbdominalA are likely acting simultaneously to repress
nessy in the other parts of the visceral mesoderm.
The scent of roses (Rosa x hybrida) is composed of hundreds of volatile molecules.Monoterpenes represent up to 70% percent of the scent content in some cultivars, such asthe Papa Meilland rose. ...Monoterpene biosynthesis in plants relies on plastid-localizedterpene synthases. Combining transcriptomic and genetic approaches, we show thatthe Nudix hydrolase RhNUDX1, localized in the cytoplasm, is part of a pathway for thebiosynthesis of free monoterpene alcohols that contribute to fragrance in roses. TheRhNUDX1 protein shows geranyl diphosphate diphosphohydrolase activity in vitro andsupports geraniol biosynthesis in planta.
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