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We showed successful detection of 200 or more copies of the S gene sequence of SARS-CoV-2 RNA within 5-30 min. We applied our one-tube assay to 46 upper respiratory swab samples for COVID-19 diagnosis, and the results from both fluorescence intensity measurements and end-point visualization were consistent with those of RT-qPCR analysis. The strategy and technique improve the sensitivity and speed of RT-RPA and CRISPR-Cas12a assays, potentially useful for both semi-quantitative and point-of-care analyses of RNA molecules.The production of cellulose nanofibrils (CNFs) continues to receive considerable attention because of their desirable material characteristics for a variety of consumer applications. There are, however, challenges that remain in transitioning CNFs from research to widespread adoption in the industrial sectors, including production cost and material performance. This Review covers CNFs produced from nonconventional fibrillation methods as a potential alternative solution. Pretreating biomass by biological, chemical, mechanical, or physical means can render plant feedstocks more facile for processing and thus lower energy requirements to produce CNFs. CNFs from nonconventional fibrillation methods have been investigated for various applications, including films, composites, aerogels, and Pickering emulsifiers. Continued research is needed to develop protocols to standardize the characterization (e.g., degree of fibrillation) of the lignocellulosic fibrillation processes and resulting CNF products to make them more attractive to the industry for specific product applications.Traumatic brain injury (TBI) induces a pathophysiologic state that can be worsened by secondary injury. [https://www.selleckchem.com/products/SB-203580.html Selleck SB203580] Monitoring brain metabolism with intracranial microdialysis can provide clinical insights to limit secondary injury in the days following TBI. Recent enhancements to microdialysis include the implementation of continuously operating electrochemical biosensors for monitoring the dialysate sample stream in real time and dexamethasone retrodialysis to mitigate the tissue response to probe insertion. Dexamethasone-enhanced continuous-online microdialysis (Dex-enhanced coMD) records long-lasting declines of glucose after controlled cortical impact in rats and TBI in patients. The present study employed retrodialysis and fluorescence microscopy to investigate the mechanism responsible for the decline of dialysate glucose after injury of the rat cortex. Findings confirm the long-term functionality of Dex-enhanced coMD for monitoring brain glucose after injury, demonstrate that intracranial glucose microdialysis is coupled to glucose utilization in the tissues surrounding the probes, and validate the conclusion that aberrant glucose utilization drives the postinjury glucose decline.ConspectusMolecular recognition is of paramount importance for modern chemical processes and has now been achieved for small molecules using well-established host-guest chemistry and adsorption-science principles. link2 In contrast, technologies for recognizing polymer structure are relatively undeveloped. Conventional polymer separation methods, which are mostly limited in practice to size-exclusion chromatography and reprecipitation, find it difficult to recognize minute structural differences in polymer structures as such small structural alterations barely influence the polymer characteristics, including molecular size, polarity, and solubility. Therefore, most of the polymeric products being used today contain mixtures of polymers with different structures as it is challenging to completely control polymer structures during synthesis even with state-of-the-art substitution and polymerization techniques. In this context, development of novel techniques that can resolve the challenges of polymer recognition and jection equilibrium at the liquid/solid interface, exhibited excellent polymer separation capability. The polymer recognition principle described in this study thus has a high probability for realizing previously unfeasible polymer separations based on monomer composition and sequences, stereoregularity, regioregularity, helicity, and block sequences in synthetic polymers and biomacromolecules.Developing hard carbon with a high initial Coulombic efficiency (ICE) and very good cycling stability is of great importance for practical sodium-ion batteries (SIBs). Defects and oxygen-containing groups grown along either the carbon edges or the layers, however, are inevitable in hard carbon and can cause a tremendous density of irreversible Na+ sites, decreasing the efficiency and therefore causing failure of the battery. Thus, eliminating these unexpected defect structures is significant for enhancing the battery performance. Herein, we develop a strategy of applying a soft-carbon coating onto free-standing hard-carbon electrodes, which greatly hinders the formation of defects and oxygen-containing groups on hard carbon. The electrochemical results show that the soft-carbon-coated, free-standing hard-carbon electrodes can achieve an ultrahigh ICE of 94.1% and long cycling performance (99% capacity retention after 100 cycles at a current density of 20 mA g-1), demonstrating their great potential in practical sodium storage systems. The sodium storage mechanism was also investigated by operando Raman spectroscopy. Our sodium storage mechanism extends the "adsorption-intercalation-pore filling-deposition" model. We propose that the pore filling in the plateau area might be divided into two parts (1) sodium could fill in the pores near the inner wall of the carbon layer; (2) when the sodium in the inner wall pores is close to saturation, the sodium could be further deposited onto the existing sodium.As a secondary Li-ion battery with high energy density, lithium-sulfur (Li-S) batteries possess high potential development prospects. One of the important ingredients to improve the safety and energy density in Li-S batteries is the solid-state electrolyte. However, the poor ionic conductivity largely limits its application for the commercial market. At present, the gel electrolyte prepared by combining the electrolyte or ionic liquid with the all-solid electrolyte is an effective method to solve the low ion conductivity of the solid electrolyte. We present a cross-linked gel polymer electrolyte with fluoroethylene carbonate (FEC) as a solid electrolyte interface (SEI) film formed for Li-S quasi-solid-state batteries, which can be simply synthesized without initiators. This gel polymer electrolyte with FEC as an additive (GPE@FEC) possesses high ionic conductivity (0.830 × 10-3 S/cm at 25 °C and 1.577 × 10-3 S/cm at 85 °C) and extremely high Li-ion transference number (tLi+ = 0.674). In addition, the strong ability toward anchoring polysulfides resulting in the high electrochemical performance of Li-S batteries was confirmed in GPE@FEC by the diffusion experiment, X-ray photoelectron spectroscopy analysis (XPS), and scanning electron microscopy (SEM) mapping of the S element. Such a high ion conductivity (IC) gel polymer electrolyte enables a competitive specific capacity of 940 mAh/g at 0.2C and supreme cycling performance for 180 cycles at 0.5C, which is far beyond that of conventional poly(ethylene oxide)-based quasi-solid-state Li-S batteries.MicroRNAs (miRNAs) play key roles in biological processes in plants, such as stress resistance, yet can hardly be quantified by an enzyme-involved terminal polymerization process due to their 2'-O-methyl modifications at the 3'-terminal. Herein, we proposed a CRISPR/Cas14a-based rolling circle amplification (termed Cas14R) assay, allowing reverse transcription-free and demethylation-free detection of plant miRNAs with single-nucleotide resolution. The employment of target-templated rolling circle amplification circumvents the extension of the unaccessible 2'-O-methyl group at the 3'-terminal. Particularly, the activated Cas14a confers the trans-cleavage activity for identifying target single-stranded DNA sequences without the necessity of the protospacer adjacent motif, generalizing the detection of miRNA sequences and the integration of different isothermal amplification techniques. Ultimately, the Cas14R assay has been applied to profile miR156a to evaluate the ripeness process of banana, indicating its feasibility in analyzing the roles of miRNAs in biological processes of plants.Atomically thin silicon nanosheets (SiNSs), such as silicane, have potential for next-generation computing paradigms, such as integrated photonics, owing to their efficient photoluminescence emission and complementary-metal-oxide-semiconductor (CMOS) compatibility. To be considered as a viable material for next-generation photonics, the SiNSs must retain their structural and optical properties at operating temperatures. However, the intersheet disorder of SiNSs and their nanoscale structure makes structural characterization difficult. Here, we use synchrotron X-ray diffraction and atomic pair distribution function (PDF) analysis to characterize the anisotropic disorder within SiNSs, demonstrating they exhibit disorder within the intersheet spacing, but have little translational or rotational disorder among adjacent SiNSs. Furthermore, we identify changes in their structural, chemical, and optical properties after being heated in an inert atmosphere up to 475 °C. We characterized changes of the annealed SiNSs using synchrotron-based total X-ray scattering, infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, electron paramagnetic resonance, absorbance, photoluminescence, and excited-state lifetime. We find that the silicon framework is robust, with an onset of amorphization at ∼300 °C, which is well above the required operating temperatures of photonic devices. Above ∼300 °C, we demonstrate that the SiNSs begin to coalesce while keeping their translational alignment to yield amorphous silicon nanosheets. In addition, our DFT results provide information on the structure, energetics, band structures, and vibrational properties of 11 distinct oxygen-containing SiNSs. Overall, these results provide critical information for the implementation of atomically thin silicon nanosheets in next-generation CMOS-compatible integrated photonic devices.α-Synuclein (αS) is an intrinsically disordered protein whose aggregation and deposition in Lewy bodies is involved in the progression of Parkinson's disease (PD) and other related disorders. The aggregation process of αS is also triggered by mutations like A53T and E46K in the SNCA gene and disruption in metal-ion homeostasis. Currently, there is no obviating therapy available in the market that could effectively prevent the progression of the disease. In this backdrop, there exists an emerging need to consider naturally occurring polyphenols and flavonoids as potential therapeutic agents against PD. In this study, we demonstrate the modulatory effect of ellagic acid (EA) against wild-type as well as mutation and metal-induced aggregation of αS. Thioflavin T (ThT) fluorescence assay suggests that EA acts on the nucleation phase of αS fibrillization, thereby increasing the lag phase from 21.33 ± 3.01 to 48.20 ± 5.05 h and reducing the fibrils growth rate from 4.60 ± 2.06 to 0.890 ± 0.36 h-1. link3 8-Anilino-1-naphthalene sulfonic acid (ANS), Congo red (CR), and intrinsic fluorescence studies indicate that the interaction of EA with αS facilitates the structural changes in the protein that lead to inhibition of fibril formation.