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The induction and development of chiral supramolecular structures from hierarchical self-assembly of achiral compounds is closely related to the evolution of life and the chiral amplification found in nature. Here we show that the combination of achiral tetraphenylethene (TPE) an AIE-active luminophore bearing four long alkyl chains via amide linkage allows the entire process of induction and control of supramolecular chirality into well-defined uniform right-handed twisted superstructures via solvent composition and polarity, i.e. solvophobic effect. We showed that the degree of twist and the pitch of the ribbons can be controlled to one-handed helical structure via solvophobic effects. The twisted superstructure assembly was visualised by scanning electron microscope (SEM) and transmission electron microscopy (TEM), furthermore, circular dichroism (CD) confirms used to determine controlled right-handed assembly. This controlled assembly of an AIE-active molecule can be of practical value; for example, as templates for helical crystallisation, catalysis and a chiral mechanochromic luminescent superstructure formation.

The present study was conducted on the tongues of six Punjab white quails. The tissues from the apex, body and root of the tongue were processed for paraffin sectioning and scanning electron microscopy studies. The tongue was triangular in shape having an apex, body and root. The dorsal surface of the apex and body was smooth whereas large lingual conical papillae were located symmetrically and converging in median line between the body and the root. There was an additional layer of conical papillae composed of two large papillae behind the main row of papillae. The tongue was lined by stratified squamous epithelium which was keratinised at the apex. The anterior lingual salivary glands were mainly serous type whereas the posterior salivary glands were mucous type. There were topographical differences in the size, shape and appearance of the exfoliated superficial cells of the dorsal surface epithelium in the apex and body of the tongue.

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