The nanoscale structures inspired by the natural catenaries can achromatically spin light wave.

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In this paper we report the conjugation of an aromatic moiety (pyrene (P), fluorene (F), or naphthalene (N)) to pentapeptides GAGAS (1), GVPVP (2), VPGVG (3), VTEEI (4), VYGGG (5), and YGFGG (6) to afford peptidic derivatives for exploring pentapeptide-based hydrogels as potential biomaterials. Most of these compounds (1F, 1P, 2F, 2P, 4F, 4P, 4N, 5F, 5N, 6F, 6P, and 6N) behave as molecular hydrogelators and can form hydrogels at minimum concentrations of gelation from 0.5 to 2.8 wt %. The fluorescence spectra of the hydrogels exhibit a significant red shift, indicating the interactions between the aromatic moieties in those hydrogels. The circular dichroism spectra indicate that the self-assembly of the hydrogelators affords helical or beta-sheet-like structures. Transmission and scanning electron microscopic examination reveals the nanofiber networks of these hydrogelators. In addition, rheological measurements show fair to excellent viscoelastic properties of these hydrogels. The balance of intermolecular aromatic-aromatic interactions and hydrogen bonds of these hydrogelators leads to their self-assembly in water and the formation of nanofibers as the matrixes of hydrogels. A total of 6 of these 18 pentapeptide derivatives--1N, 2N, 3F, 3P, 3N, and 5P--fail to form hydrogels under the conditions tested, likely due to unbalanced intermolecular interactions. This work suggests that aromatic-aromatic interactions are useful and favorable forces for creating molecular nanofibers and supramolecular hydrogels.

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The control of polarization and wavefront plays an important role in many optical systems. In this work, a monolayer metasurface is proposed to simultaneously realize circular asymmetric transmission (AT) and wavefront shaping based on asymmetric spin-orbit interactions. Circularly polarized incidence, accompanied with arbitrary wavefront modulation, experiences spin-selected destructive or constructive interference. An extinction ratio of ≈10:1 and an AT parameter of ≈0.69 at 9.6 µm, as well as a full width halfmaximum of ≈2.9 µm (≈30% of the peak wavelength), are measured with the designed metasurface. These measured results are more than four times of those achieved with previous monolayer chiral structures. As far as it is known, this is the first report on the realization of simultaneous giant AT and arbitrary wavefront modulation with only one metasurface. Due to its fabrication simplicity and the multifunctionality of the designed metasurface, this work may provide a promising route to replace bulky cascading optical components with only one ultrathin metasurface for chiroptical spectroscopy, chiral imaging, optical communication, and so forth.

The present survey aims to study the prevalence and clinical characteristics of non-carious cervical lesions (NCCLs) and cervical dentine hypersensitivity (CDH), as well as their possible risk factors in a general population in China. A total of 1023 subjects were included in the present study. Each subject completed a structured interview, and all teeth of each subject were examined by a practitioner to determine NCCLs and CDH. Teeth with NCCLs and CDH were diagnosed according to the tooth wear index and by a blast of air from a triple syringe, respectively. Binary logistic regression was completed by analysing the association of risk factors with the occurrence of NCCLs and CDH. Loss of attachment (LOA) and gingival recession (GR) of teeth with NCCLs and/or CDH were measured using Williams periodontal probe. The diagnoses of NCCLs and CDH established following a clinical assessment yielded an overall prevalence of 61·7% and 27·1%, respectively. The 60-69 age group had the greatest proportion of subjects with NCCLs or CDH. The pre-molars were the most commonly affected teeth type with NCCLs or CDH. The proportion of teeth with CDH associated with NCCLs increased significantly with age, but the proportion of teeth with CDH only associated with LOA or GR decreased slowly with age. The single variables and interactive effects of variables associated with the occurrence of NCCLs include the following: age group, occupation type, method of toothbrushing, frequency and method of toothbrushing, and method of toothbrushing and duration of a toothbrush used. Gender, age group, occupation type and frequency of toothbrushing were associated with the occurrence of CDH. The current study presented higher prevalence of NCCLs and CDH in a general Chinese population. Both diseases were closely associated with age and periodontal status. The portion of the population with NCCLs or CDH had different risk factors.

We synthesized a group of silole regioisomers 1(x,y), whose photoluminescence varied dramatically with its regiostructure. By internally hindering the intramolecular rotation, we succeeded in creating a novel silole (1(3,4)) that is strongly luminescent in solutions and whose fluorescence quantum yield in acetone is as high as 83%. We revealed that 1(3,4) was a sensitive chemosensor capable of optically discriminating nitroaromatic regioisomers of p-, o-, and m-nitroanilines. Against general belief, crystal formation of 1(2,4) blue-shifted its emission color and boosted its emission efficiency. The light-emitting diode based on the crystal of 1(2,4) emitted a strong blue light (464 nm) in a high current efficiency (5.86 cd/A).