4D Additive-Subtractive Manufacturing of Shape Memory Ceramics.

The development of high-temperature structural materials, such as ceramics, is limited by their extremely high melting points and the difficulty in building complicated architectures. Four-dimensional (4D) printing helps enhance the geometrical flexibility of ceramics. However, ceramic 4D printing systems are limited by the separate processes for shape and material transformations, low accuracy of morphing systems, low resolution of ceramic structures, and their time-intensive nature. Here, a paradigm for a one-step shape/material transformation, high-2D/3D/4D-precision, high-efficiency, and scalable 4D additive-subtractive manufacturing of shape memory ceramics is developed. Original/reverse and global/local multimode shape memory capabilities are achieved using macroscale SiOC-based ceramic materials. The uniformly deposited Al2 O3 -rich layer on the printed SiOC-based ceramic lattice structures results in an unusually high flame ablation performance of the complex-shaped ceramics. The proposed framework is expected to broaden the applications of high-temperature structural materials in the aerospace, electronics, biomedical, and art fields.

Anti-Melanogenic Effect from Submerged Mycelial Cultures of Ganoderma weberianum.

Compounds from Lingzhi has been demonstrated the ability for inhibiting tyrosinase (a key enzyme in melanogenesis) activity. In this study, we investigated the anti-melanogenic activity from the submerged mycelial culture of Ganoderma weberianum and elucidated the skin lightening mechanism by B16-F10 murine melanoma cells. From the cellular context, several fractionated mycelium samples exhibited anti-melanogenic activity by reducing more than 40% extracellular melanin content of B16-F10 melanoma cells. In particular, the fractionated chloroform extract (CF-F3) inhibited both secreted and intracellular melanin with the lowest dosage (25 ppm). Further analysis demonstrated that CF-F3 inhibited cellular tyrosinase activity without altering its protein expression. Taken together, our study has demonstrated that the chemical extracts from submerged mycelial culture of G. weberianum have the potential to serve as an alternative anti-melanogenic agent.

Tyrosinase-based TLC Autography for anti-melanogenic drug screening.

Tyrosinase-based TLC (thin layer chromatography) was developed for screening of anti-melanogenic drugs. In particular, this technique enables researchers to identify melanogenic inhibitor(s) in tested mixtures with the naked eye. In comparison with traditional colorimetric screening assays for tyrosinase inhibitor(s), not only is tyrosinase-based TLC a more cost-effective option (nearly one-tenth the enzyme cost of colorimetric methods) but also is a more sensitive detection approach for kojic acid (KA), a standard anti-melanogenic drug. The detection limit of tyrosinase-based TLC and colorimetric tyrosinase assay for KA was 0.0125 and 1.25 µg, respectively, demonstrating that the former was 100-fold more sensitive than the latter to determine the tyrosinase inhibitory rate of KA. Furthermore, the results of this method have demonstrated excellent precision by Gage Repeatability and Reproducibility (Gage R&R), with the variation of total Gage R&R being 28.24%. To verify the applicability of tyrosinase-based TLC, this platform was employed to screen melanogenic inhibitor(s) from Ganoderma formosanum extracts and two of all fractions (GFE-EA F4, F5) obtained showed depigmenting activity. It is noteworthy that these two fractions also exerted anti-melanogenesis activity on zebrafish, therefore verifying the credibility of tyrosinase-based TLC. In sum, this technique provides new insight into the discovery of novel melanogenic inhibitor(s).

Translation and validation study of the Chinese version Iconographical Falls Efficacy Scale-Short Version (Icon-FES).

BACKGROUND: The 30-item Iconographical Falls Efficacy Scale (Icon-FES) is the first instrument developed to assess older people's concern about falling using pictures. The short version of Icon-FES (10-item Icon-FES) was translated and adapted to a local Chinese version, and its psychometric properties was evaluated in Chinese older people. METHODS: A forward-backward translation procedure was used, followed by an expert panel review to finalize the 10-item Chinese Icon-FES. One hundred and sixteen Hong Kong Chinese older people (65-95 years) were assessed using the 10-item Chinese Icon-FES in conjunction with the Chinese version 7-item Falls Efficacy Scale-International (FES-I (Ch)). RESULTS: Five of the 10 items in the Icon-FES were modified to achieve the conceptual and cultural relevance in local context. The final Chinese Icon-FES had excellent internal consistency (Cronbach's alpha = 0.91) and test-retest reliability (intra-class correlation coefficient ICC = 0.93). High correlation was found between the Chinese Icon-FES and FES-I (Ch) (r = .75, p < .001). Construct validity was supported by its ability to discriminate between groups related to demographic and fall risk factors. CONCLUSIONS: The Chinese Icon-FES is a valid, efficient and easy-to-use instrument for understanding of local Chinese older people's concerns about falling in Hong Kong.