Schrödinger

About: Schrödinger is a based out in . It is known for research contribution in the topics: Sputtering & Ion. The organization has 1621 authors who have published 2200 publications receiving 81554 citations.

Desorption of nanoclusters from gold nanodispersed layers by 72 keV Au400 ions: Experiment and molecular dynamics simulation

Abstract: The interaction of 72 keV Au 400 ions (with a diameter of approximately 2 nm) with nanodispersed gold targets has been studied. These interactions are dominated by elastic collisions. The gold nanodispersed target with 2–12 nm nanoislets was bombarded with a fluence of 1.7 × 10 12 ions/cm 2 . The desorbed nanoclusters were collected on carbon foils supported by TEM-grids. Intact 29 nm gold nanoclusters were found on the collectors. The desorption yield (normalized to the total cross-section of the projectile-cluster interaction) was estimated to be 0.62 nanocluster/projectile. Preliminary estimates were made using molecular dynamic simulations for comparison with the experimental results.

Two sets of RNAi components are required for heterochromatin formation in trans triggered by truncated transgenes.

Abstract: Across kingdoms, RNA interference (RNAi) has been shown to control gene expression at the transcriptional- or the post-transcriptional level. Here, we describe a mechanism which involves both aspects: truncated transgenes, which fail to produce intact mRNA, induce siRNA accumulation and silencing of homologous loci in trans in the ciliate Paramecium We show that silencing is achieved by co-transcriptional silencing, associated with repressive histone marks at the endogenous gene. This is accompanied by secondary siRNA accumulation, strictly limited to the open reading frame of the remote locus. Our data shows that in this mechanism, heterochromatic marks depend on a variety of RNAi components. These include RDR3 and PTIWI14 as well as a second set of components, which are also involved in post-transcriptional silencing: RDR2, PTIWI13, DCR1 and CID2. Our data indicates differential processing of nascent un-spliced and long, spliced transcripts thus suggesting a hitherto-unrecognized functional interaction between post-transcriptional and co-transcriptional RNAi. Both sets of RNAi components are required for efficient trans-acting RNAi at the chromatin level and our data indicates similar mechanisms contributing to genome wide regulation of gene expression by epigenetic mechanisms.

Tetraphosphacyclopentadienyl‐ und Triphosphaallyl‐Liganden in Eisenkomplexen

Abstract: Vielseitige Phosphorchemie: Die Reaktion des Bicyclotetraphosphan-Komplexes 1 mit PCtBu lieferte gleich zwei neuartige Produkte mit Polyphosphorliganden: den Triphosphaallyl-verbruckten Zweikernkomplex 2 und das 1,2,3,4-Tetraphosphaferrocen 3. Cp=5-C5H2tBu3.

Cyanphosphorverbindungen, 8. Das ungewöhnliche Anion P2C10N102–

Abstract: Die Reaktion P(CN)3 + CN− (als [18]Krone-6-Natriumsalz) fuhrt uber das nur spektroskopisch erkennbare P(CN) zur Disproportionierung PIII PI + PV. Als Produkte konnen (mit Ph3PCHPPh3 + als Kation) P(CN) und P2C10N102− (1) gefast werden. In letzterem sind ein Dicyanphosphino-und ein Pentacyanophosphatrest, –P(CN)2 bzw. – P(CN)5−, uber eine anionische Aminomalononitrilbrucke miteinander verbunden. Cyanophosphorus Compounds, 8. The Unusual Anion P2C10N102− The reaction P(CN)3 + CN− (as [18]crown-6-sodium salt) leads via the spectroscopically identified P(CN)4− to a disproportionation PIII PI + PV. P(CN)2− and P2C10N102− (1) have been isolated as products (with Ph3PCHPPh3+ as counter ion). In the latter an anionic aminomalononitrile bridge connects a dicyanophosphino and a pentacyanophosphate group, –P(CN)2 and – P(CN)5−, respectively.