341 research outputs found
Interspecific competition between Drosophila melanogaster and Drosophila simulans: temperature effect on competitive ability and fitness components
International audienc
Linkage disequilibrium between enzymatic loci in natural populations of Drosophila simulans
International audienc
Palladium-Catalyzed Allylation/Benzylation of H-Phosphinate Esters with Alcohols
The Pd-catalyzed direct alkylation of H-phosphinic acids and hypophosphorous acid with allylic/benzylic alcohols has been described previously. Here, the extension of this methodology to H-phosphinate esters is presented. The new reaction appears general, although its scope is narrower than with the acids, and its mechanism is likely different. Various alcohols are examined in their reaction with phosphinylidene compounds R1R 2P(O)H
Methyl (2′S,3′S)-3,4-O-(2′,3′-dimethoxybutane-2′,3′-diyl)-α-l-rhamnopyranoside: a glycosyl acceptor
The title compound, C13H24O7, is the product of the ketalization of methyl l-(+)-rhamnopyranoside with 2,3-butanedione. It crystallizes with two molecules in the asymmetric unit, which are connected by O—H⋯O hydrogen bonds. The C-3,4 diequatorial hydroxy groups of the methyl l-(+)-rhamnopyranoside were protected, leaving the C-2 hydroxy group free. The l-(+)-rhamnopyranoside and 2′,3′-dimethoxybutane-2′,3′-diyl rings adopt chair conformations and all methoxy groups are in axial positions. The absolute configuration was assumed from the synthesis
Benzyl(methyl)phosphinic acid
The title compound, C8H11O2P, is a phosphinic compound with a tetracoordinate pentavalent P atom. The phosphinic function plays a predominant role in the cohesion of the crystal structure, both by forming chains along the b axis via strong intermolecular O—H⋯O hydrogen bonds and by cross-linking these chains perpendicularly via weak intermolecular C—H⋯O hydrogen bonds, generating a two-dimensional network parallel to (001)
Distorted Sex Ratios: A Window into RNAi-Mediated Silencing
Some species ofDrosophila have unequal ratios of males to females, and now two genes--one responsible for such sex-ratio distortion and one that suppresses it--have been identified in one of these species
Resistance to natural and synthetic gene drive systems
Scientists are rapidly developing synthetic gene drive elements intended for release into natural populations. These are intended to control or eradicate disease vectors and pests, or to spread useful traits through wild populations for disease control or conservation purposes. However, a crucial problem for gene drives is the evolution of resistance against them, preventing their spread. Understanding the mechanisms by which populations might evolve resistance is essential for engineering effective gene drive systems. This review summarizes our current knowledge of drive resistance in both natural and synthetic gene drives. We explore how insights from naturally occurring and synthetic drive systems can be integrated to improve the design of gene drives, better predict the outcome of releases and understand genomic conflict in general
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