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This study introduces a novel approach for synthesizing Benzoxazine‐centered Polychiral Polyheterocycles (BPCPHCs) via an innovative asymmetric carbene‐alkyne metathesis‐triggered cascade. Overcoming challenges associated with intricate stereochemistry and multiple chiral centers, the catalytic asymmetric Carbene Alkyne Metathesis‐mediated Cascade (CAMC) is employed using dirhodium catalyst/Brønsted acid co‐catalysis, ensuring precise stereo control as validated by X‐ray crystallography. Systematic substrate scope evaluation establishes exceptional diastereo‐ and enantioselectivities, creating a unique library of BPCPHCs. Pharmacological exploration identifies twelve BPCPHCs as potent Nav ion channel blockers, notably compound 8 g. In vivo studies demonstrate that intrathecal injection of 8 g effectively reverses mechanical hyperalgesia associated with chemotherapy‐induced peripheral neuropathy (CIPN), suggesting a promising therapeutic avenue. Electrophysiological investigations unveil the inhibitory effects of 8 g on Nav1.7 currents. Molecular docking, dynamics simulations and surface plasmon resonance (SPR) assay provide insights into the stable complex formation and favorable binding free energy of 8 g with C5aR1. This research represents a significant advancement in asymmetric CAMC for BPCPHCs and unveils BPCPHC 8 g as a promising, uniquely acting pain blocker, establishing a C5aR1‐Nav1.7 connection in the context of CIPN. [ABSTRACT FROM AUTHOR]

A molecular probe is demonstrated to be an effective semi‐invasive technique to measure the local environments of biomaterials. Environmental probes based on fluorescence intensity and lifetime are well studied as temperature sensors. However, usually both fluorescence intensity and lifetime of reported molecular probes depend on various local environments, such as temperature, pH, and ionic strength. It is a big challenge to distinguish the specific environmental effects on the fluorescence. Herein, the violet phosphorus quantum dots (VPQDs) are demonstrated to be effective fluorescence molecular probes to distinguish temperature or pH environment variation. The fluorescence intensity and bandwidth of VPQDs are demonstrated to be linearly correlated to a wide range of temperatures (283–363 K), while the fluorescence lifetime of VPQDs is demonstrated to be temperature‐independent. However, the fluorescence lifetime is demonstrated to be linearly correlated to pH value. Additionally, good water dispersibility, superior photo‐ and thermal stability, and excellent reversibility are also obtained by VPQDs. More importantly, the high sensitivity of fluorescence intensity to temperature instead of pH environments and the high sensitivity of fluorescence lifetime to pH environments instead of temperature allow VPQDs to be distinguishable biosensors to temperature and pH environments. [ABSTRACT FROM AUTHOR]

Semiconducting layered violet phosphorus, the most stable phosphorus allotrope, has recently been successfully produced with large single crystal sizes and high yields. A promising anisotropy is expected by the reduced symmetry of violet phosphorus in various properties. The in‐plane crystallographic anisotropy and cleavage edge orientation are especially important to the exfoliated 2D structures for their electronic, photonic, magnetic, and mechanic applications. However, the anisotropy of violet phosphorus has not been studied. Here, a fast and nondestructive way is reported to identify the crystallographic orientation of 2D violet phosphorus nanoflakes by a single polarized Raman spectrum. The 2D violet phosphorus nanoflakes have been found to have preferred in‐plane cleavage edges along ‐[P2][P8][P2][P9]‐ tubular strands with <1, 1, 0> edge alignment. The b‐axis (a‐axis) direction has been demonstrated to be easily identified that forms an angle of 45° or 135° from the cleavage edge by the intensity of Ag mode, especially the appearance or disappearance of 491 cm–1, under parallel configuration using polarized Raman scattering. A simple and fast method has been developed to identify the crystallographic orientation of violet phosphorus nanoflakes by a single Raman spectrum to obtain the corresponding a‐axis and b‐axis. [ABSTRACT FROM AUTHOR]

Herein, the effects of heat treatment on the microstructure, tensile properties, and low‐cycle fatigue properties of the LZ91 Mg–Li alloy are investigated. The results indicate that after heat treatment, the α‐phase undergoes spheroidization, and a portion of the needle‐like α‐phase is distributed at the β‐phase grain boundary; in addition, the ultimate tensile strength (UTS) and elongation of the material increase by 9.6% and 20%, respectively, and the low‐cycle fatigue life is improved. The increase in the UTS of the specimen is attributed to the precipitation of the needle‐like α‐phase, whereas that in material plasticity is attributed to α‐phase spheroidization after heat treatment. It is observed that fatigue cracks all originate on the surface of the specimens, predominantly in the β‐phase. The needle‐like α‐phase suppresses the initiation of macro fatigue cracks, and the increased α‐phase microhardness decelerates the crack growth rate, thereby improving the low‐cycle fatigue life of the alloy. [ABSTRACT FROM AUTHOR]

Illness as the result of ingesting bacterially contaminated foodstuffs represents a significant annual loss of human quality of life and economic impact globally. Significant research investment has recently been made in developing new materials that can be used to construct food contacting tools and surfaces that might minimize the risk of cross‐contamination of bacteria from one food item to another. This is done to mitigate the spread of bacterial contamination and resultant foodborne illness. Internet‐based literature search tools such as Web of Science, Google Scholar, and Scopus were utilized to investigate publishing trends within the last 10 years related to the development of antimicrobial and antifouling surfaces with potential use in food processing applications. Technologies investigated were categorized into four major groups: antimicrobial agent–releasing coatings, contact‐based antimicrobial coatings, superhydrophobic antifouling coatings, and repulsion‐based antifouling coatings. The advantages for each group and technical challenges remaining before wide‐scale implementation were compared. A diverse array of emerging antimicrobial and antifouling technologies were identified, designed to suit a wide range of food contact applications. Although each poses distinct and promising advantages, significant further research investment will likely be required to reliably produce effective materials economically and safely enough to equip large‐scale operations such as farms, food processing facilities, and kitchens. [ABSTRACT FROM AUTHOR]

The chemical stability of 2D MXene nanosheets in aqueous dispersions must be maintained to foster their widespread application. MXene nanosheets react with water, which results in the degradation of their 2D structure into oxides and carbon residues. The latter detrimentally restricts the shelf life of MXene dispersions and devices. However, the mechanism of MXene degradation in aqueous environment has yet to be fully understood. In this work, the oxidation kinetics is investigated of Ti3C2Tx and Ti2CTx in aqueous media as a function of initial pH values, ionic strengths, and nanosheet concentrations. The pH value of the dispersion is found to change with time as a result of MXene oxidation. Specifically, MXene oxidation is accelerated in basic media by their reaction with hydroxyl anions. It is also demonstrated that oxidation kinetics are strongly dependent on nanosheet dispersion concentration, in which oxidation is accelerated for lower MXene concentrations. Ionic strength does not strongly affect MXene oxidation. The authors also report that citric acid acts as an effective antioxidant and mitigates the oxidation of both Ti3C2Tx and Ti2CTx MXenes. Reactive molecular dynamic simulations suggest that citric acid associates with the nanosheet edge to hinder the initiation of oxidation. [ABSTRACT FROM AUTHOR]