Silicon nanowhiskers in the diameter range of 70 to 200 nm were grown on 〈111〉-oriented silicon substrates by molecular-beam epitaxy. Assuming the so-called “vapor–liquid–solid” (VLS) growth process to operate, we initiated the growth by using small clusters of gold at the silicon interface as seeds. The in situ generation of the Au clusters as well as the growth parameters of the whiskers are discussed. The experimentally observed radius dependence of the growth velocity of the nanowhiskers is opposite to what is known for VLS growth based on chemical vapor deposition and can be explained by an ad-atom diffusion on the surface of the whiskers.

This review describes recent progress in adhesive supramolecular polymeric materials constructed from macrocycle-based host–guest interactions.

Traditional (1D, 2D, and 3D) codes are widely used to provide convenient readouts of encoded information. However, manipulating and transforming the encoded information is typically difficult to achieve. Here, the preparation of three fluorescent (blue, green, and red) hydrogels containing both tetracationic receptor-anion recognition motifs and gel-specific fluorophores is reported, which may be used as building blocks to construct through physical adhesion fluorescent color 3D codes (Code A, Code B, and Code C) that may be read out by a smartphone. As a result, parts of the individual gel components that make up Code B can be replaced with other gel building blocks to form Code A via a cut and adhesion approach. A fluorophore responsive to ammonia is further incorporated into one of the hydrogels. This allows the gel block-derived pattern that makes up Code C to be converted to Code A by chemical means. Therefore, the encoded information produced by patterns of the present hydrogels may be transformed through either physical action or by exposure to a chemical stimulus. Due to the nature of the soft materials involved, the codes can be used as wearable materials.

4-(1H-phenanthro[9,10-d]imidazol-2-yl)benzaldehyde 1 was rationally designed as a novel ratiometric fluorescent probe for cysteine and homocysteine. Upon addition of cysteine or homocysteine, notably, the probe displayed a very large (125 nm) hypsochromic shift in emission due to switching off intramolecular charge transfer. This large emission wavelength shift may allow probe 1 to be employed for quantitatively detecting Cys/Hcy.

a b s t r a c tMicroRNAs (miRNA) have emerged as key players in carcinogenesis. Here, we investigated the role of miR-137 in the pathogenesis of lung cancer. The downregulation of miR-137 in lung cancer cells could be rescued following inhibition of DNA methylation. Ectopic expression of miR-137 in lung cancer cells significantly downregulated Cdc42, Cdk6 and induced G1 cell cycle arrest, leading to a significant decrease in cell growth in vivo and in vitro. Further, both Cdc42 and Cdk6 were confirmed as targets of miR-137. Crown

Epithelial-mesenchymal transition (EMT) has an established role in promoting tumor progression and the acquisition of therapeutic resistance. Here, the EMT phenotype was detected in cisplatin-resistant ovarian cancer tissues and cell lines, and correlated with decreased miR-186 expression, increased Twist1 expression, chemoresistance and poor prognosis in epithelial ovarian cancer (EOC) patients. Introducing miR-186 into EOC cells led to a reduction in twist family bHLH transcription factor 1 (Twist1) expression along with morphological, functional and molecular changes consistent with mesenchymal-to-epithelial transition, G1 cell-cycle arrest and enhanced cell apoptosis, which consequently rendered the cells more sensitive to cisplatin in vitro and in vivo. Furthermore, luciferase reporter and rescue assay results showed that the EMT and drug resistance reversal in response to miR-186 was mediated by Twist1. Collectively, these findings implicate miR-186 as an attractive candidate for overcoming chemoresistance in ovarian cancer therapy.

We report an expanded “Texas-sized” molecular box (AzoTxSB) that incorporates photoresponsive azobenzene bridging subunits and anion recognition motifs. The shape of this box can be switched through light induced E ↔ Z photoisomerization of the constituent azobenzenes. This allows various anionic substrates to be bound and released by using different forms of the box. Control can also be achieved using other environmental stimuli, such as pH and anion competition.

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