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Vegetation optical depth (VOD), as a microwave-based estimate of vegetation water and biomass content, is increasingly used to study the impact of global climate and environmental changes on vegetation. However, current global operational VOD products have a coarse spatial resolution (~25 km), which limits their use for agriculture management and vegetation dynamics monitoring at regional scales (1–5 km). This study aims to retrieve high-resolution VOD from the C-band Sentinel-1 backscatter data over a grassland of the Heihe River Basin in northwestern China. The proposed approach used an analytical solution of a simplified Water Cloud Model (WCM), constrained by given soil moisture estimates, to invert VOD over grassland with 1 km spatial resolution during the 2018–2020 period. Our results showed that the VOD estimates exhibited large spatial variability and strong seasonal variations. Furthermore, the dynamics of VOD estimates agreed well with optical vegetation indices, i.e., the mean temporal correlations with normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), and leaf area index (LAI) were 0.76, 0.75, and 0.75, respectively, suggesting that the VOD retrievals could precisely capture the dynamics of grassland. [ABSTRACT FROM AUTHOR]

Due to the lack of suitable chemical tools, probing the protein‐specific glycation is highly challenging. Herein, we present a strategy based on glycation chemical reporter and proximity‐induced FRET signal readout for visualizing protein‐specific glycation in living cells. We first developed a bioorthogonal glucose analogue, 6‐azido‐6‐deoxy‐D‐glucose (6AzGlc), as a novel glycation chemical reporter. Two types of DNA probes, glycation conversion probe and protein targeting probe, were designed to attach to glycation adducts and target proteins, respectively. After the protein was glycated by 6AzGlc, two DNA probes were sequentially applied to the target protein, triggering proximity‐induced FRET signal readout. This strategy was successfully used to visualize glucose glycation of several proteins, including PD‐L1 and integrin. More importantly, this strategy allowed us to analyze corresponding biological functions of glycated protein in the native environment. [ABSTRACT FROM AUTHOR]

• IgM was tested in convalescent individuals following SARS-CoV-2 infection 1 year previously. • Of survivors, 23.9% were positive for anti-SARS-CoV-2 IgM. • Higher IgM titers were detected in convalescent individuals with severe COVID-19. • IgM testing does not replace PCR testing in detecting acute SARS-CoV-2 infection. • IgM testing should not determine the need to quarantine. [ABSTRACT FROM AUTHOR]

Cell surface receptors are important proteins that mediate communication between the cells and their outside environment, and also play essential roles in the control of a wide variety of biological processes, such as cell cycle, proliferation, communication, migration and apoptosis. Receptor oligomerization is an essential signal transduction mechanism that cell surface receptors use to transmit extracellular signals into the internal cytosol cellular machinery. Therefore, regulating receptor oligomerization provides an opportunity to customize cellular signaling and to direct cellular behavior in a user-defined manner. Some techniques have been developed for receptor oligomerization regulation, such as chemically induced dimerization (CID) and optogenetics, which involve traditional genetic engineering. However, the process of genetic manipulation is time-consuming, unpredictable and inefficient. Thus, development of nongenetic strategies for precisely regulating receptor oligomerization remains a desirable goal. Recently, along with the utilization of DNA, protein, small molecules and stimuli-responsive materials-based nongenetic engineering strategies, various receptor oligomerization and multiple cellular behaviors could be regulated, including migration, proliferation, apoptosis, differentiation and immune responses, etc. In this review, we aim to systematically introduce advances in the development of nongenetic engineering strategies for regulating receptor oligomerization, and provide insights into the existing challenges and future perspectives of this field. [ABSTRACT FROM AUTHOR]