Organic crystals are generally brittle and tend to crack under applied stress. Doped organic crystals are even more brittle because of lattice defects. Herein, the first doped organic crystals 1d@2d, ...which display elastic bending ability under applied stress, are reported. Moreover, the potential applications of elastic‐doped crystals 1d@2d in flexible optoelectronics are impressively demonstrated. The elastic crystals 1d@2d with high quality and large size are crystalized by a simple and unique “self‐doping” process, which is a regular solution evaporation of crude product 1d (2,5‐dihydro‐3,6‐bis(octylamino)terephthalate) containing a minute amount of 2d (3,6‐bis(octylamino)terephthalate) as the oxidized byproduct. The host 1d is easily crystallized to form elastic crystals but is nonfluorescent, while the guest 2d has poor crystallinity and is highly emissive. The doping approach integrates the advantages of both 1d and 2d, and thus endows doped crystals 1d@2d with good elasticity as well as intense orange fluorescence. Taking these advantages, the application potentials of these doped crystals 1d@2d are evaluated by measuring optical waveguide and amplified spontaneous emission in both the straight and bent states.
Elastic‐doped organic crystals 1d@2d are crystalized by a simple and unique “self‐doping” process. Taking advantage of the good elasticity and intense fluorescence, a flexible optical waveguide and amplified spontaneous emission are realized in bent crystals 1d@2d, highlighting the feature of elasticity and the potential applications in flexible optoelectronics.
Understanding of the structure-mechanical properties relationship in organic crystals can potentially facilitate the design of crystals with desired mechanical properties through crystal engineering. ...To understand and predict crystal mechanical properties, including tableting behavior, a number of computational methods have been developed to analyze crystal structure. These include visualization, attachment energy calculation, topological analysis, energy framework, and elasticity tensor calculation. However, different methods often lead to conflicting predictions. There is a need for a computational tool kit for predicting crystal mechanical properties from crystal structures. Using α-oxalic acid anhydrous (OAA) and dihydrate (OAD) as a model system, we have systematically compared their predictive accuracy of the mechanical properties, experimentally determined using powder compaction and nanoindentation. We have found that crystal plasticity can be accurately predicted based on energy framework combined with topological analysis and DFT calculated elasticity tensor. Although very useful in characterizing crystal packing features, structure visualization, topology analysis, and attachment energy calculations alone are insufficient for accurately identifying the slip planes and predicting mechanical properties and tableting behavior of organic crystals.
Visual perception refers to the process of organizing, identifying, and interpreting visual information in environmental awareness and understanding. With the rapid progress of multimedia acquisition ...technology, research on visual perception has been a hot topic in the academical field and industrial applications. Especially after the introduction of artificial intelligence theory, intelligent visual perception has been widely used to promote the development of industrial production towards intelligence. In this article, we review the previous research and application of visual perception in different industrial fields such as product surface defect detection, intelligent agricultural production, intelligent driving, image synthesis, and event reconstruction. The applications basically cover most of the intelligent visual perception processing technologies. Through this survey, it will provide a comprehensive reference for research on this direction. Finally, this article also summarizes the current challenges of visual perception and predicts its future development trends.
Stimulation emission depletion (STED) microscopy enables ultrastructural imaging of organelle dynamics with a high spatiotemporal resolution in living cells. For the visualization of the ...mitochondrial membrane dynamics in STED microscopy, rationally designed mitochondrial fluorescent markers with enhanced photostability are required. Herein, we report the development of a superphotostable fluorescent labeling reagent with long fluorescence lifetime, whose design is based on a structurally reinforced naphthophosphole fluorophore that is conjugated with an electron-donating diphenylamino group. The combination of long-lived fluorescence and superphotostable features of the fluorophore allowed us to selectively capture the ultrastructures of the mitochondrial cristae with a resolution of ∼60 nm when depleted at 660 nm. This chemical tool provides morphological information of the cristae, which has so far only been observed in fixed cells using electron microscopy. Moreover, this method gives information about the dynamic ultrastructures such as the intermembrane fusion in different mitochondria as well as the intercristae mergence in a single mitochondrion during the apoptosis-like mitochondrial swelling process.
With the growing shortage of fossil energy and the increasing of concerns over global climate changes and environmental problems have driven the development of alternative energy sources. Recently, ...great interest has been oriented towards the development of sustainable resources, especially the utilization of lignocellulosic biomass, a renewable and the most abundant source of biomass originating from plant photosynthesis in nature. Catalytic conversion of renewable cellulosic biomass can produce a series of compounds such as 5-hydroxymethylfurfural (HMF) and 2,5-dimethylfuran (DMF) which are important platform compounds and ideal renewable alternative to fossil fuels. To obtain the renowned bio-based platform molecules, various catalysts and reaction systems have been used in the past decade years. To fully understand current biomass to HMF and DMF development, it is necessary to have an overview and comparison of different homogeneous and heterogeneous catalysts. The reaction systems also exhibit a remarkable impact on the yield and distribution of products with different catalysts. General trends and future research directions of using biomass for HMF, DMF production are also discussed systematically.
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•Shifting from fossil resources to sustainable biomass for chemicals production is important in both academic and our society.•A comprehensive review about the catalytic conversion of biomass into HMF and DMF have been presented.•Catalysts, and reaction systems for the production of HMF and DMF developed in the last few years are discussed.•The scale-up conversion of biomass and the process economy analysis of HMF and DMF production are also discussed.
Early diagnosis and monitoring of SARS-CoV-2 virus is essential to control COVID-19 outbreak. In this study, we propose a promising surface enhanced Raman scattering (SERS)-based COVID-19 biosensor ...for ultrasensitive detection of SARS-CoV-2 virus in untreated saliva. The SERS-immune substrate was fabricated by a novel oil/water/oil (O/W/O) three-phase liquid-liquid interfaces self-assembly method, forming two layers of dense and uniform gold nanoparticle films to ensure the reproducibility and sensitivity of SERS immunoassay. The detection was performed by an immunoreaction between the SARS-CoV-2 spike antibody modified SERS-immune substrate, spike antigen protein and Raman reporter-labeled immuno-Ag nanoparticles. This SERS-based biosensor was able to detect the SARS-CoV-2 spike protein at concentrations of 0.77 fg mL−1 in phosphate-buffered saline and 6.07 fg mL−1 in untreated saliva. The designed SERS-based biosensor exhibited excellent specificity and sensitivity for SARS-CoV-2 virus without any sample pretreatment, providing a potential choice for the early diagnosis of COVID-19.
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•A new SERS-based COVID-19 biosensor was developed for ultrasensitive detection of SARS-CoV-2 virus.•A novel three-phase interfaces self-assembly method was applied for fabricating the SERS-immune substrate.•The SERS-immune substrate assembled by highly dense and uniform Au NPs can improve the reproductivity of SERS immunoassay.•The biosensor can detect the SARS-CoV-2 spike protein at ultra-low concentration of 6.07 fg mL−1 in untreated saliva.•The biosensor exhibits excellent specificity and sensitivity for SARS-CoV-2 virus without any sample pretreatment.
STING (stimulator of interferon genes) is a central molecule that binds to cyclic dinucleotides produced by the cyclic GMP-AMP synthase (cGAS) to activate innate immunity against microbial infection. ...Here we report that STING harbors classic LC-3 interacting regions (LIRs) and mediates autophagy through its direct interaction with LC3. We observed that poly(dA:dT), cGAMP, and HSV-1 induced STING-dependent autophagy and degradation of STING immediately after TBK1 activation. STING induces non-canonical autophagy that is dependent on ATG5, whereas other autophagy regulators such as Beclin1, Atg9a, ULK1, and p62 are dispensable. LIR mutants of STING abolished its interaction with LC3 and its activation of autophagy. Also, mutants that abolish STING dimerization and cGAMP-binding diminished the STING-LC3 interaction and subsequent autophagy, suggesting that STING activation is indispensable for autophagy induction. Our results thus uncover dual functions of STING in activating the immune response and autophagy, and suggest that STING is involved in ensuring a measured innate immune response.
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•The co-pyrolysis of lignin and waste cooking oil yielded up to 82.6% mono-aromatics.•The highest synergistic extent for mono-aromatic production was 52.1%.•Lignin-derived model ...compounds were selected for co-pyrolysis to study the mechanism.•Guaiacol was more active to be converted to aromatics than o-cresol and phenol.•The mechanism of catalytic co-pyrolysis of lignin and waste cooking oil was proposed.
Lignin and waste cooking oil are wastes from paper and food industries, respectively. In this work, the catalytic fast co-pyrolysis of lignin and waste cooking oil for the production of aromatics in a pyroprobe was investigated with an aim to improve the utilization of lignin waste and waste cooking oil. Furthermore, lignin-derived monomers, including phenol, o-cresol, and guaiacol, were also used as model feedstock for the catalytic co-pyrolysis in order to study the mechanism underlying aromatic formation. The mechanistic study helped lay theoretical foundation for the industrial application of the co-pyrolysis process. The effects of catalyst and waste cooking oil addition on co-pyrolysis product fractional yield and selectivity were studied. High amount of waste cooking oil in the feedstock with appropriate catalyst-to-feedstock ratio (3:1) contributed to high peak-area yields of the total detected compounds and aromatics. The alkylation and demethoxylation of phenols were enhanced at high ratios of catalyst to feedstock and waste cooking oil to lignin. When the ratio of waste cooking oil to lignin was 1:1, the highest mono-aromatic selectivity (82.6%) and synergistic extent (52.1%) for mono-aromatic production were obtained. The catalytic co-pyrolysis of the lignin-derived monomers and waste cooking oil showed that guaiacol was the most active compound to be converted to aromatics, followed by o-cresol, and phenol. The reaction mechanism underlying the formation of aromatics from the synergistic conversion of aliphatics and phenolics was elaborated.
Manganese (Mn) is essential for many physiological processes, but its functions in innate immunity remain undefined. Here, we found that Mn2+ was required for the host defense against DNA viruses by ...increasing the sensitivity of the DNA sensor cGAS and its downstream adaptor protein STING. Mn2+ was released from membrane-enclosed organelles upon viral infection and accumulated in the cytosol where it bound directly to cGAS. Mn2+ enhanced the sensitivity of cGAS to double-stranded DNA (dsDNA) and its enzymatic activity, enabling cGAS to produce secondary messenger cGAMP in the presence of low concentrations of dsDNA that would otherwise be non-stimulatory. Mn2+ also enhanced STING activity by augmenting cGAMP-STING binding affinity. Mn-deficient mice showed diminished cytokine production and were more vulnerable to DNA viruses, and Mn-deficient STING-deficient mice showed no increased susceptibility. These findings indicate that Mn is critically involved and required for the host defense against DNA viruses.
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•Mn2+ is released from organelles and accumulates in the cytosol upon virus infection•Mn2+ activates anti-viral innate immunity via the cGAS-STING pathway•Mn2+ increases the sensitivity of cGAS to dsDNA and promotes STING activation•Mn-deficient mice are more vulnerable to DNA viruses
The cGAS-STING pathway is required for host defense against DNA viruses. Wang et al. find that upon virus infection, Manganese (Mn2+) is released from organelles into the cytosol and facilitates the activation of cGAS and STING. Their findings identify a role for Mn in innate immune activation and host anti-viral defense.
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