Alternate bearing in 'Hass' avocado: fruit load-induced changes in bud auxin homeostasis are associated with flowering repression.

In 'Hass' avocado (Persea americana), fruit presence reduces next season flowering. Recent fruit tree studies proposed that heavy fruit load (HFL) generates an auxin (indole-3-acetic acid, IAA) signal in the buds that represses flowering. However, the nature of this signal remains unknown.

Stochastic Sensing of Chloride Anions Using an α-Hemolysin Pore with a semiaza-Bambusuril Adapter.

Pores containing molecular adapters provide internal selective binding sites, thereby allowing the stochastic sensing of analytes. Herein, we demonstrate that semiaza-bambusuril (BU) acts as a non-covalent molecular adapter when lodged within the lumen of the wild-type α-hemolysin (WT-αHL) protein pore. Because the bambusurils are recognized as anion receptors, the anion binding site within the adapter-nanopore complex allows the detection of chloride anions, thus converting a non-selective pore into an anion sensor.

Selective Perchlorate Sensing Using Electrochemical Impedance Spectroscopy with Self-Assembled Monolayers of semiaza-Bambusurils.

In the last two decades, perchlorate salts have been identified as environmental pollutants and recognized as potential substances affecting human health. We describe self-assembled monolayers (SAMs) of novel semiaza-bambus[6]urils (semiaza-BUs) equipped with thioethers or disulfide (dithiolane) functionalities as surface-anchoring groups on gold electrodes. Cyclic voltammetry (CV) with Fe(CN) as a redox probe, together with X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and ellipsometry, were employed to characterize the interactions at the interface between the anchoring groups and the metal substrate.

-Bambusurils are anion-specific transmembrane transporters.

-Bambus[6]urils efficiently transport anions across lipid membranes. A systematic modification of their lipophilic side chains to include various alkyl groups and thioethers reveals that the most efficient chloride transporters are those that agree with Lipinski's rule-of-lipophilicity, exhibiting clog  values close to 5. Furthermore, vesicle anion-transport assays show that the new anion-transporters are independent of the cation identity but exhibit high anion selectivity, NO > Br > Cl > SO, in agreement with the Hofmeister series.

Flat corannulene: when a transition state becomes a stable molecule.

Flat corannulene has been considered so far only as a transition state of the bowl-to-bowl inversion process. This study was driven by the prediction that substituents with strong steric repulsion could destabilize the bowl-shaped conformation of this molecule to such an extent that the highly unstable planar geometry would become an isolable molecule. To examine the substituents' effect on the corannulene bowl depth, optimized structures for the highly-congested decakis(-butylsulfido)corannulene were calculated.