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Knowledge of aerosol radiative effects in the Tibetan Plateau (TP) is limited due to the lack of reliable aerosol optical properties, especially the single scattering albedo (SSA). We firstly reported in situ measurement of SSA in Lhasa using a cavity enhanced albedometer (CEA) at λ = 532 nm from 22nd May to 11th June 2021. Unexpected strong aerosol absorbing ability was observed with an average SSA of 0.69. Based on spectral absorptions measured by Aethalometer (AE33), black carbon (BC) was found to be the dominated absorbing species, accounting for about 83% at λ = 370 nm, followed by primary and secondary brown carbon (BrCpri and BrCsec). The average direct aerosol radiative forcing at the top of atmosphere (DARFTOA) was 2.83 W/m2, indicating aerosol warming effect on the Earth‐atmosphere system. Even though aerosol loading is low, aerosol heating effect plays a significant role on TP warming due to strong absorbing ability. Plain Language Summary: The Tibetan Plateau (TP) has experienced rapid warming over the past decades, but the key factors affecting TP climate change haven't yet been clearly understood. Aerosol single scattering albedo (SSA) is a key optical parameter determining aerosol warming or cooling effect; however, reliable SSA measurement is scarce in TP. This study firstly reported in situ measurement of SSA in Lhasa and explored the direct radiative effect of aerosol on TP warming. Strong aerosol absorption, mainly contributed by black carbon (BC), was observed with an average SSA value of 0.69 in this city. Besides Lhasa, other sites over TP were also reported with low SSA (≤0.77) from surface measurement. The strong aerosol absorption could cause heating effect on the Earth‐atmosphere system. To relieve TP warming, reasonable pollutant emission control strategies should be taken urgently to weaken aerosol absorbing ability. Key Points: Unexpected low aerosol single scattering albedo was observed in Lhasa via in situ measurement of multiple optical parameters simultaneouslyBlack carbon was the dominant contributor (∼83%) to aerosol absorption at 370 nm, followed by primary and secondary brown carbonThe strong absorption in Lhasa exerted positive direct aerosol radiative forcing (warming effect) at the top of atmosphere [ABSTRACT FROM AUTHOR]

Pluripotent stem cell‐derived small extracellular vesicles (PSC‐sEVs) have demonstrated great clinical translational potential in multiple aging‐related degenerative diseases. Characterizing the PSC‐sEVs is crucial for their clinical applications. However, the specific marker pattern of PSC‐sEVs remains unknown. Here, the sEVs derived from two typical types of PSCs including induced pluripotent stem cells (iPSC‐sEVs) and embryonic stem cells (ESC‐sEVs) were analysed using proteomic analysis by liquid chromatography with tandem mass spectrometry (LC‐MS/MS), and surface marker phenotyping analysis by nanoparticle flow cytometry (NanoFCM). A group of pluripotency‐related proteins were found to be enriched in PSC‐sEVs by LC‐MS/MS and then validated by Western Blot analysis. To investigate whether these proteins were specifically expressed in PSC‐sEVs, sEVs derived from seven types of non‐PSCs (non‐PSC‐sEVs) were adopted for analysis. The results showed that PODXL, OCT4, Dnmt3a, and LIN28A were specifically enriched in PSC‐sEVs but not in non‐PSC‐sEVs. Then, commonly used surface antigens for PSC identification (SSEA4, Tra‐1‐60 and Tra‐1‐81) and PODXL were gauged at single‐particle resolution by NanoFCM for surface marker identification. The results showed that the positive rates of PODXL (>50%) and SSEA4 (>70%) in PSC‐sEVs were much higher than those in non‐PSC‐sEVs (<10%). These results were further verified with samples purified by density gradient ultracentrifugation. Taken together, this study for the first time identified a cohort of specific markers for PSC‐sEVs, among which PODXL, OCT4, Dnmt3a and LIN28A can be detected with Western Blot analysis, and PODXL and SSEA4 can be detected with NanoFCM analysis. The application of these specific markers for PSC‐sEVs identification may advance the clinical translation of PSCs‐sEVs. [ABSTRACT FROM AUTHOR]

Recently, eutectogels have gained significant attention as promising materials for wearable devices. However, developing eutectogels with integrated stretchability, good toughness, self‐healing, and self‐adhesive properties through non‐covalent scaffold assembly is a major challenge. In this study, a fully physically crosslinked double‐network (DN) eutectogel was fabricated by exploiting the high solubility and gelation of gellan gum in a deep eutectic solvent (DES) to form the first physically crosslinked network and combining it with supramolecular poly (2‐hydroxyethyl acrylate‐choline chloride, HEA‐ChCl). The resulting gel showed high stretchability (1835 %), toughness (7.65 MJ m−3), desirable ionic conductivity (0.41 mS cm−1), adhesion, and high transparency. Assembling the gel into strain sensors allows precise monitoring of human motion (finger, wrist, elbow, and knee). The results of this study suggest that gellan gum/poly (ChCl‐HEA) DN eutectogels have significant potential as highly sensitive and reliable strain sensors for wearable technology applications. [ABSTRACT FROM AUTHOR]

Owing to the advantages of temperature resistance, low cost, and biocompatibility, deep eutectic solvent (DES)‐based ionic conductive gels have attracted increasing research interest for flexible devices in recent years. However, current DES gels are all based on hydrophilic DES, which tend to absorb a large amount of environmental moisture, resulting in gel softening and adversely affecting the durability of the device. In this work, we highlight for the first time that N,N‐dimethylacrylamide monomer, and the obtained polymer can form hydrogen‐bonding networks with hydrophobic DES, methyl trioctyl ammonium chloride/ethyl 4‐hydroxybenzoate (1:2), thereby obtaining a hydrophobic DES‐based gel through photo‐polymerization. The resultant DES gel displays high stretchability (~900%), toughness (341.14 kJ m−3), anti‐fatigue property (recovery after 500 compression cycles), desirable conductivity (0.12 mS cm−1), adhesiveness and high transparency (>90% visible light transmittance). Notably, the hydrophobic DES‐based gel absorbs only 2 wt% water but exhibits significant water‐induced stiffening after exposing in ambient air for 1 week. These properties lead to the successful realization of the DES gels as wearable sensors to precisely monitor human motion. This work may open new avenues for the development of hydrophobic DES‐based gel ionotronics with functional performance. [ABSTRACT FROM AUTHOR]

Bacterial biofilms are associated with chronic infectious diseases and are highly resistant to conventional antibiotics. Antimicrobial bacteriocins are alternatives to conventional antibiotics and are characterized by unique cell‐killing mechanisms, including pore formation on cell membranes, nuclease activity, and cell wall synthesis inhibition. Here, we used cell‐free protein synthesis to rapidly evaluate the anti‐biofilm activities of colicins E1, E2, and E3. We found that E2 (with DNase activity) most effectively killed target biofilm cells (i.e., the K361 strain) while leaving nontargeted biofilms intact. We then engineered probiotic Escherichia coli microorganisms with genetic circuits to controllably synthesize and secrete colicin E2, which successfully inhibited biofilms and killed preformed indicator biofilms. Our findings suggest that colicins rapidly and selectively kill target biofilm cells in multispecies biofilms and demonstrate the potential of using microorganisms engineered to produce antimicrobial colicin proteins as live therapeutic strategies to treat biofilm‐associated infections. [ABSTRACT FROM AUTHOR]

A direct strategy for the iron‐catalyzed oxidative coupling C2‐functionalization of benzofurans with unactivated diarylmethanes has been established. The developed procedure provides a straightforward access to C2‐benzylation of benzofurans from simple and abundant starting materials without the need for pre‐functionalization or specific substituted functional groups of both, substrates and coupling partners. [ABSTRACT FROM AUTHOR]

Photonic elastomers (PEs) that can tune their colors through adjusting the lattice spacing of incorporated colloidal particles during mechanical deformation have shown great promise in visualized strain/stress sensors. However, the unsatisfactory structural color and narrow‐spectrum responsiveness limit their broad applications. Herein, carbon‐coated Fe3O4 nanoparticles (Fe3O4@C NPs) with a high refractive index (RI) and broad light absorption are employed for the construction of PEs with brilliant colors and broad‐spectrum responsiveness by incorporating the Fe3O4@C NPs into amino‐terminated poly(dimethylsiloxane) (amino‐PDMS) polymer through supramolecular interactions. The inherent light‐absorbing property, high RI, and supramolecular‐induced short‐range ordered arrangement of Fe3O4@C NPs imparts the PEs with brilliant and angle‐independent structural color. By optimizing the content of Fe3O4@C NPs in the PEs, broad‐spectrum responsiveness (stopband shifting ≈223 nm) and excellent recovery properties under a large strain can be achieved. The dynamic and reversible interaction endows the PEs with a healable capability. More interestingly, the incorporated Fe3O4@C NPs with photothermal capability can effectively absorb light and convert it into heat under light irradiation (solar light or near‐infrared laser), accelerating healing of the damaged PEs. This study provides a new strategy for bioinspired construction of PEs for applications in the fields of sensing, colorful coating, and display. [ABSTRACT FROM AUTHOR]