Search

Two-dimensional (2D) molybdenum sulfide (MoS 2) is considered as a promising catalyst for hydrogen evolution reaction (HER), originated from its abundant hydrogen evolution active sites. However, the HER performance of MoS 2 is currently hindered by the limited exposed density of the active sites and low conductivity. Herein, we report a facile and scalable electrospinning technique to fabricate 2D MoS 2 nanoplates doped with phosphorus within one-dimensional nitrogen doped-carbon nanofibers (NCNFs-MoS 2 |P) as a highly efficient HER catalyst. The space-confined growth with the presence of NCNFs avoided the stacking and aggregation of the MoS 2 nanoplates, resulting in more exposed edge sites. The introduction of phosphorus atoms further activated the surface of MoS 2 and enhanced the electron transfer. The overpotential of NCNFs-MoS 2 |P reached 98 mV at 10 mA cm−2, exhibiting excellent HER catalytic activity. Besides, almost no decay was observed after the stability test (5000 cycles or 20 h). The density functional calculations (DFT) elucidated that the incorporation of phosphorus atoms significantly improved the electrical conductivity and decreased the H adsorption energy barrier on MoS 2 , leading to a high catalytic performance of NCNFs-MoS 2 |P. [ABSTRACT FROM AUTHOR]

[Display omitted] • A controllable hydrophilic/superhydrophobic patterned coating is reported. • The superhydrophobic pattern presents rough ridge-like microstructures and opaque state. • The hydrophilic pattern exhibits water-triggered opaque to translucent transition. • The patterned coating is successfully applied in optical information encryption/decryption. • The information revealing demonstrates long-term stability and great reusability. Anti-counterfeiting technologies are crucial for securing the authenticity and proof of commodities, in which the optical information encryption/decryption has attracted extensive attention for its overriding advantages of visibility and convenience. Inspired by the unique transparency transformation phenomenon of Diphylleia grayi petals, a controllable hydrophilic/superhydrophobic patterned coating with water-triggered opaque to translucent transition is proposed through the construction of a superhydrophobic coating, subsequent air plasma etching under a mask, and final hydrophilic modification to introduce stable invisible patterns. The superhydrophobic region exhibits great water repellency with a water contact angle (WCA) at 157°, while the hydrophilic region quickly absorbs water with a WCA at 61°. The patterned coating presents an opaque state for the serious light scattering induced by the rough microstructure and large refractive index difference between the coating and air, while the hydrophilic patterns on the coating transform to translucent after water infiltration for the reduced roughness and close refractive indexes of the coating and water. The information revealing is rapid and reversible, and demonstrates heat and long-term stability and great reusability. The findings conceivably stand out as a new methodology to fabricate controllable superwettable coatings with optical information encryption/decryption capability for application in anti-counterfeiting. [ABSTRACT FROM AUTHOR]

Barnacles are notorious marine fouling organisms. Their successful attachment to a substrate requires that they search for an appropriate habitat during their cyprid stage. A chemical cue called SIPC (Settlement-Inducing Protein Complex) has been shown to play a key role in the induction of cyprid gregarious settlement; however, the underlying biochemical mechanism remains unclear. Here, RNA-seq was used to examine the gene expression profiles of Amphibalanus amphitrite cyprids in response to SIPC and to identify SIPC-activated intracellular signaling pathways. A total of 389 unigenes were differentially expressed in response to SIPC, and cement protein genes were not among them. KEGG enrichment analysis suggested that SNARE interactions in the vesicular transport pathway were significantly influenced by SIPC treatment, indicating a possible role for SIPC in triggering protein transportation and secretion. Several genes with specific functions in metamorphosis were found among the differentially expressed genes (DEGs). GO (Gene Ontology) enrichment analysis revealed that the DEGs were significantly enriched in enamel mineralization pathways, suggesting that SIPC may also be involved in the activation of mineralization. • We observed the behaviors of cyprid antennules in SIPC supplemented FSW. • The expression of cement protein genes was not remarkably influenced by SIPC treatment. • SIPC induces highly expression of genes involved in SNARE interactions in the vesicular transport pathway. • GPCR may initiate the signal transduction cascade leading to settlement. [ABSTRACT FROM AUTHOR]

Abstract Olfactory receptors (OR), a group of classic membrane proteins, plays a vital role in insect reproduction and acclimatization. Deciphering the molecular mechanism of insect olfaction could enhance pest control and environmental protection. Studies on ORs have faced a major bottleneck due to the notoriously strong hydrophobicity of ORs, which results in difficult expression in heterologous cell systems. Here, we demonstrated that insect ORs could be functionally produced using the E. coli cell-free protein synthesis system (CFPS), in which the highest yield of total ORs is 350 μg per 1 ml reaction. We tested the effects of detergent types and concentrations on soluble expression of ORs. The ORs showed a classic α-helical infrared spectrum. Quartz crystal microbalance (QCM) was used to demonstrate that ORs fold correctly and respond to their ligands. This is the first report that insect OR42a could be functionally produced in vitro. This approach may facilitate the development of biomimetic olfactory biosensors and may also be utilized for drug positioning and development, environmental protection and agriculture. Highlights • ORCO and OR42a can be high-level expressed by an E. coli cell-free protein synthesis system. • Brij35 and Brij58 can increase soluble cell-free production for ORCO and OR42a. • ORCO and OR42a exhibit a classic α-helix secondary structure by FTIR. • Propyl acetate is able to be specifically recognized by the QCM sensor coated with ORCO and OR42a in vitro. [ABSTRACT FROM AUTHOR]

Barnacles robustly adhere themselves to diverse submarine substrates through a proteinaceous complex termed the “barnacle cement”. Previous studies have indicated that certain peptides derived from some barnacle cement proteins can self-assemble into amyloid fibrils. In this study, we assessed the self-assembly behavior of a full-length 19 kDa cement protein from Balanus albicostatus ( Bal cp19k) in different buffers. Results of Thioflavin T binding assay, transmission electron microscopy, and Fourier transform infrared spectroscopy suggested that the bacterial recombinant Bal cp19k was able to aggregate into typical amyloid fibrils. The time required for the self-assembly process was close to that required for the complete curing of barnacle cement complex. Moreover, the solubility of Bal cp19k amyloid deposits in guanidine hydrochloride and urea was same as that of the cured cement. These results indicated the inherent self-assembling nature of Bal cp19k, implying that the amyloid fibril formation plays a critical role in barnacle cement curing procedure and its insolubility. Our results should be conducive to understanding barnacle underwater adhesion mechanisms and have implications in the development of new-generation antifouling techniques and in the designing of novel wet adhesives for biomedical and technical applications. [ABSTRACT FROM AUTHOR]