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The presence of protein aggregates in numerous human diseases underscores the significance of detecting these aggregates to comprehend disease mechanisms and develop novel therapeutic approaches for combating these disorders. Despite the development of various biosensors and fluorescent probes that selectively target amyloid fibers or amorphous aggregates, there is still a lack of tools capable of simultaneously detecting both types of aggregates. Herein, we demonstrate the quantitative discernment of amorphous aggregates by QM‐FN‐SO3, an aggregation‐induced emission (AIE) probe initially designed for detecting amyloid fibers. This probe easily penetrates the membranes of the widely‐used prokaryotic model organism Escherichia coli, enabling the visualization of both amorphous aggregates and amyloid fibers through near‐infrared fluorescence. Notably, the probe exhibits sensitivity in distinguishing the varying aggregation propensities of proteins, regardless of whether they form amorphous aggregates or amyloid fibers in vivo. These properties contribute to the successful application of the QM‐FN‐SO3 probe in the subsequent investigation of the antiaggregation activities of two outer membrane protein (OMP) chaperones, both in vitro and in their physiological environment. Overall, our work introduces a near‐infrared fluorescent chemical probe that can quantitatively detect amyloid fibers and amorphous aggregates with high sensitivity in vitro and in vivo. Furthermore, it demonstrates the applicability of the probe in chaperone biology and its potential as a high‐throughput screening tool for protein aggregation inhibitors and folding factors. [ABSTRACT FROM AUTHOR]

Unpredictable in vivo therapeutic feedback of reactive oxygen species (ROS) efficiency is the major bottleneck of photodynamic therapy (PDT). Herein, novel PDT‐based nanotheranostics Pa–Mn&CH‐A@P are elaborately constructed for in vivo tracking biodistribution and in situ self‐reporting PDT, which innovatively unites magnetic resonance imaging (MRI) and chemiluminescence (CL) signals. Taking advantages of the versatility of lanthanide coordination chemistry and flash nanoprecipitation (FNP) technology, photosensitizers, MRI, and CL agents are unprecedently integrated within a stable and uniform nanotheranostic. Specifically, MRI signal offers detailed dose distribution of nanotheranostics with high‐spatial resolution, and CL signal timely performs in situ evaluation of ROS generation with high sensitivity. This dual‐modal MRI/CL nanotheranostic makes a breakthrough in high fidelity feedback for oral tumor, conquering the inherent unpredictable obstacles on spatially and sensitively reporting PDT. [ABSTRACT FROM AUTHOR]

Fluorescent compounds with aggregation-induced emission (AIE) characteristics (or AIEgens) have garnered significant research interest for various applications. The establishment of new AIE mechanisms coupled with quantitative prediction power is crucial to accelerate the development of novel AIE materials. Herein, we report the discovery of a new AIE mechanism, known as restriction of intramolecular bending (RIB), using computational chemistry and experimental validation. In RIB, the structural bending of the fluorophore scaffold caused by steric effects leads to fluorescence quenching in a dilute solution; fluorescence is only recovered in the aggregate state when the bending is inhibited. This RIB mechanism affords a practical guide for the quantitative molecular design of AIEgens, i.e., by converting traditional aggregation-caused quenching (ACQ) fluorophores to AIEgens through simple structural modifications. We believe that the introduction of the RIB mechanism paves a new avenue for the rational development of functional AIEgens. [ABSTRACT FROM AUTHOR]

In order to realize the dynamic analysis of regional soil moisture content in the upper reaches of Xiashan Reservoir in Weihe River Basin, Weifang City, Shandong Province, a regional soil moisture dynamic analysis model based on hyperspectral remote sensing technology is proposed. The process of predicting and deducing the soil water content through the spectral information of remote sensing images, surface parameters and other data can reflect the soil spectral information. The band sensitive to the change of soil moisture in remote sensing image is directly extracted, which is used as the independent variable input in the soil water logging inversion model, and the process of soil moisture prediction is conducted with the measured soil moisture value as the dependent variable input. The SI-1, SI-2 and other water spectral indexes that can reflect the water information are constructed, and the water spectral index used for soil water content retrieval is constructed through various relationships between bands. Compared with the spectral reflectance alone, the use of water spectral index greatly improves the retrieval accuracy. The particle filter algorithm is used to assimilate the observed data and simulated data to obtain the assimilated soil moisture. Error evaluation indicators are used to evaluate the accuracy of the obtained assimilation results and further use different particle numbers and observation errors to conduct multiple data assimilation experiments to explore the sensitivity of particle numbers and observation errors to the assimilation results. The root mean square error (RMSE), relative error (RE) and mean absolute error (MAE) are used to test and verify the effect of data assimilation. The test shows that the dynamic analysis of the regional soil moisture content in the upper reaches of Xiashan Reservoir in the Fangwei River basin by using this method the distribution map obtained by dividing the vegetation coverage are more consistent with the actual situation in terms of the proportion of different soil water salinization degrees, the regional distribution of water, etc. The idea of using hyperspectral remote sensing to retrieve soil moisture is effective. [ABSTRACT FROM AUTHOR]

Uniting photothermal therapy (PTT) with magnetic resonance imaging (MRI) holds great potential in nanotheranostics. However, the extensively utilized hydrophobicity-driven assembling strategy not only restricts the intramolecular motion-induced PTT, but also blocks the interactions between MR agents and water. Herein, we report an aggregation-induced emission luminogen (AIEgen)-mediated polyelectrolyte nanoassemblies (APN) strategy, which bestows a unique "soft" inner microenvironment with good water permeability. Femtosecond transient spectra verify that APN well activates intramolecular motion from the twisted intramolecular charge transfer process. This de novo APN strategy uniting synergistically three factors (rotational motion, local motion, and hydration number) brings out high MR relaxivity. For the first time, APN strategy has successfully modulated both intramolecular motion and magnetic relaxivity, achieving fluorescence lifetime imaging of tumor spheroids and spatio-temporal MRI-guided high-efficient PTT., (© 2023 Wiley-VCH GmbH.)

The occurrence and transmission of chirality is a fascinating characteristic of nature. However, the intermolecular transmission efficiency of circularly polarized luminescence (CPL) remains challenging due to poor through-space energy transfer. We report a unique CPL transmission from inducing the achiral acceptor to emit CPL within a specific liquid crystal (LC)-based intermolecular system through a circularly polarized fluorescence resonance energy transfer (C-FRET), wherein the luminescent cholesteric LC is employed as the chirality donor, and rationally designed achiral long-wavelength aggregation-induced emission (AIE) fluorophore acts as the well-assembled acceptor. In contrast to photon-release-and-absorption, the chirality transmission channel of C-FRET is highly dependent upon the energy resonance in the highly intrinsic chiral assembly of cholesteric LC, as verified by deliberately separating the achiral acceptor from the chiral donor to keep it far beyond the resonance distance. This C-FRET mode provides a de novo strategy concept for high-level information processing for applications such as high-density data storage, combinatorial logic calculation, and multilevel data encryption and decryption., (© 2021 Wiley-VCH GmbH.)