Two pairs of enantiomers, (−) and (+)-securidanes A (1 and 2) and B (3 and 4) featuring unprecedented triarylmethane (TAM) skeletons, were isolated from Securidaca inappendiculata. Their structures were established by spectroscopic data, X-ray crystallography, and CD analysis. A plausible biosynthetic pathway for 1−4 based on the co-isolated precursors was proposed. Bioinspired total synthesis of 1−4 was completed in high yield, which in turn corroborated the biosynthetic hypothesis. Compounds 1−4 showed good inhibition against protein tyrosine phosphatase 1B (PTP1B). The molecular docking demonstrated that the strongest inhibitor 3 (IC₅₀ = 7.52 μM) reaches deeper into the binding pocket and has an additional H-bond.

The assembly of superstructures from building blocks is of fundamental importance for engineering materials with distinct morphologies and properties, and deepening our understanding of self-assembly processes in nature. Up to now, it is still a great challenge in materials science to construct multiple-component superstructure with unprecedented architectural complexity and symmetry from molecular. Here, we demonstrate an improved one-pot hydrothermal carbonization of biomass strategy that is capable of fabricating unprecedented asymmetric carbonaceous bivalve-like superstructures with in suit generated solid particles and ordered porous polymers as two kinds of building blocks. In our system, different building blocks can be controllably generated, and they will assemble into complex superstructures through a proposed “cooperative assembly of particles and ordered porous polymers” mechanism. We believe that this assembly principle will open up new potential fields for the synthesis of superstructures with diverse morphologies, compositions, and properties.

The search for artificial structure with tunable topological properties is an interesting research direction of today’s topological physics. Here, we introduce a scheme to realize topological nodal states with a three-dimensional periodic inductor-capacitor (LC) circuit lattice, where the topological nodal line state and Weyl state can be achieved by tuning the parameters of inductors and capacitors. A tight-binding-like model is derived to analyze the topological properties of the LC circuit lattice. The key characters of the topological states, such as the drumhead-like surface bands for nodal line state and the Fermi arc-like surface bands for Weyl state, are found in these systems. We also show that the Weyl points are stable with the fabrication errors of electric devices.

Upon initiation at a start codon, the ribosome must maintain the correct reading frame for hundreds of codons in order to produce functional proteins. While some sequence elements are able to trigger programmed ribosomal frameshifting (PRF), very little is known about how the ribosome normally prevents spontaneous frameshift errors that can have dire consequences if uncorrected. Using high resolution ribosome profiling data sets, we discovered that the translating ribosome uses the 3′ end of 18S rRNA to scan the AUG-like codons after the decoding process. The postdecoding mRNA:rRNA interaction not only contributes to predominant translational pausing, but also provides a retrospective mechanism to safeguard the ribosome in the correct reading frame. Partially eliminating the AUG-like “sticky” codons in the reporter message leads to increased +1 frameshift errors. Remarkably, mutating the highly conserved CAU triplet of 18S rRNA globally changes the codon “stickiness”. Further supporting the role of “sticky” sequences in reading frame maintenance, the codon composition of open reading frames is highly optimized across eukaryotic genomes. These results suggest an important layer of information embedded within the protein-coding sequences that instructs the ribosome to ensure reading frame fidelity during translation.

Visible-light color filters using patterned nanostructures have attracted much interest due to their various advantages such as compactness, enhanced stability, and environmental friendliness compared with traditional pigment or dye-based optical filters. While most existing studies are based on planar nanostructures with lateral variation in size, shape, and arrangement, the vertical dimension of structures is a long-ignored degree of freedom for the structural colors. Herein, we demonstrate a synthetic platform for transmissive color filter array by coordinated manipulations between height-varying nanocavities and their lateral filling fractions. The thickness variation of those nanocavities has been fully deployed as an alternative degree of freedom, yielding vivid colors with wide gamut and excellent saturation. Experimental results show that the color-rendering capability of the pixelated nanocavities can be still retained as pixels are miniaturized to 500 nm. Crosstalk between closely spaced pixels of a Bayer color filter arrangement was calculated, showing minimal crosstalk for 1  µm² square subpixels. Our work provides an approach to designing and fabricating ultracompact color filter arrays for various potential applications including stained-glass microprints, microspectrometers, and high-resolution image sensing systems.

An effective, value-added use of the large amounts of olefinic compounds produced in the processing of petroleum, aside from ethylene and propylene, has been a long outstanding challenge. Here, we developed a novel heterogeneous polymerization method, beyond emulsion/dispersion/suspension, termed self-stabilized precipitation (2SP) polymerization, which involves the nucleation and growth of nanoparticles (NPs) of a well-defined size without the use of any stabilizers and multifunctional monomers (crosslinker). This technique leads to two revolutionary advances: (1) the generation of functional copolymer particles from single olefinic monomer or complex olefinic mixtures (including C4/C5/C9 fractions) in large quantities, which open a new way to transform huge amount of unused olefinic compounds in C4/C5/C9 fractions into valuable copolymers, and (2) the resultant polymeric NPs possess a self-limiting size and narrow size distribution, therefore being one of the most simple, efficient, and green strategies to produce uniform, size-tunable, and functional polymeric nanoparticles. More importantly, the separation of the NPs from the reaction medium is simple and the supernatant liquid can be reused; hence this new synthetic strategy has great potential for industrial production.

Nanoparticle bioreactivity critically depends upon interaction between proteins and nanomaterials (NM). The formation of the “protein corona” (PC) is the effect of such nanoprotein interactions. PC has a wide usage in pharmaceuticals, drug delivery, medicine, and industrial biotechnology. Therefore, a detailed in-vitro, in-vivo, and in-silico understanding of nanoprotein interaction is fundamental and has a genuine contemporary appeal. NM surfaces can modify the protein conformation during interaction, or NMs themselves can lead to self-aggregations. Both phenomena can change the whole downstream bioreactivity of the concerned nanosystem. The main aim of this review is to understand the mechanistic view of NM-protein interaction and recapitulate the underlying physical chemistry behind the formation of such complicated macromolecular assemblies, to provide a critical overview of the different models describing NM induced structural and functional modification of proteins. The review also attempts to point out the current limitation in understanding the field and highlights the future scopes, involving a plausible proposition of how artificial intelligence could be aided to explore such systems for the prediction and directed design of the desired NM-protein interactions.