Behavioral evidence of olfactory imprinting during embryonic and larval stages in lake sturgeon.

Many migratory fishes are thought to navigate to natal streams using olfactory cues learned during early life stages. However, direct evidence for early-life olfactory imprinting is largely limited to Pacific salmon, and other species suspected to imprint show life history traits and reproductive strategies that raise uncertainty about the generality of the salmonid-based conceptual model of olfactory imprinting in fishes. Here, we studied early-life olfactory imprinting in lake sturgeon (), which have a life cycle notably different from Pacific salmon, but are nonetheless hypothesized to home via similar mechanisms.

Unraveling an Alternative Mechanism in Polymer Self-Assemblies: An Order-Order Transition with Unusual Molecular Interactions between Hydrophilic and Hydrophobic Polymer Blocks.

Polymer self-assembly leading to cooling-induced hydrogel formation is relatively rare for synthetic polymers and typically relies on H-bonding between repeat units. Here, we describe a non-H-bonding mechanism for a cooling-induced reversible order-order (sphere-to-worm) transition and related thermogelation of solutions of polymer self-assemblies. A multitude of complementary analytical tools allowed us to reveal that a significant fraction of the hydrophobic and hydrophilic repeat units of the underlying block copolymer is in close proximity in the gel state.

Solid microemulsion preconcentrates on pH responsive metal-organic framework for tableting.

Poorly water-soluble drugs are frequently formulated with lipid-based formulations including microemulsions and their preconcentrates. We detailed the solidification of drug-loaded microemulsion preconcentrates with the acid-sensitive metal-organic framework ZIF-8 by X-ray powder diffraction and solid-state nuclear magnetic resonance spectroscopy. Adsorption and desorption dynamics were analyzed by fluorescence measurement, high-performance liquid chromatography, dynamic light scattering and H-DOSY experiments using the model compounds Nile Red, Vitamin K, and Lumefantrine.

Mechanistic insights into template-driven polyoxovanadate self-assembly: the role of internal and external templates.

The self-assembly of molecular metal oxides, polyoxometalates (POMs), can be controlled using internal or, more rarely, external templates. Here, we explore how the interplay between internal templates (halides, oxoanions) and organic external templates (protonated cyclene species) affect the self-assembly of a model polyoxovanadate cluster, [VOX] (X = Cl, Br, NO). A combination of crystallographic analyses, spectroscopic studies and as well as solid-state V NMR spectroscopy provide critical insights into the initial formation of an intermediate vanadate species formed during the process.