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The development of modern technologies has acclimatized biosensors to complicated applicable scenarios with integrated properties as a whole instead of the pursuit of a single-point breakthrough. Here, we targeted a few concerns in the development of enzyme-based biosensors, including stability, analyte enrichment, and signal transduction, and developed a general biosensing model utilizing enzymes, aggregation-induced emission (AIE) luminogens, and stimuli-responsive framework materials as the units. We propose such proof-of-concept of glucose biosensors by coencapsulating glucose oxidase and AIE-type gold nanoclusters into acid-sensitive zeolite imidazolate framework (ZIF)-8 nanocrystals. The acid-activated degradation of ZIF-8 bridges the molecular signals produced by the enzyme-catalytic reaction of glucose and the photon signals generated by ZIF-8-induced AIE effects of gold nanoclusters, resulting in the "turn-off" model nanoprobes for glucose detection with high selectivity. After embedding the nanoprobes into hollow-out tapes, the formed paper biosensors can conveniently detect glucose with the help of a smartphone.

In the published reviews of natural language pre-training technology, most literatures only elaborate neural network pre-training technologies or a brief introduction to traditional pre-training technologies, which may result in the development process of natural language pre-training dissected artificially from natural language processing. Therefore, in order to avoid this phenomenon, this paper covers the process of natural language pre-training with four points as follows. Firstly, the traditional natural language pre-training technologies and neural network pre-training technologies are introduced according to the updating route of pre-training technology. With the characteristics of related technologies analyzed, compared, this paper sums up the process of development context and trend of natural language processing technology. Secondly, based on the improved BERT (bidirectional encoder representation from transformers), this paper mainly introduces the latest natural language processing models from two aspects and sums up these models from pre-training mechanism, advantages and disadvantages, performance and so on. The main application fields of natural language processing are presented. Furthermore, this paper explores the challenges and corresponding solutions to natural language processing models. Finally, this paper summarizes the work of this paper and prospects the future development direction, which can help researchers understand the development of pre-training technologies of natural language more comprehensively and provide some ideas to design new models and new pre-training methods.

Recently, multiplexed ratiometric fluorescence sensors for detecting several analytes have received much interest because of their multifunctionality. Here, we fabricate a novel trinity fluorescent nanoprobe in which one small-molecule fluorophore, blue-emissive dityrosine (diTyr) residues, and two nanomaterial fluorophores, green-emissive CdS quantum dots (CdSQDs) and red-emissive gold nanoclusters (AuNCs), are cocaged in a bovine serum albumin (BSA) molecule. The large differences of Stokes shifts among diTyr residues, CdSQDs, and AuNCs ensure their emission at a single excitation wavelength. The nanoprobes can be facilely integrated using two-step synthetic reactions. DiTyr residues and AuNCs are formed and bound to the protein cage through the redox reaction between Au3+ and tyrosine residues of BSA, and the CdSQDs are followed to be conjugated to the modified BSA cage-templated CdS combination reaction. With established benign biocompatibility, the nanoprobes can ratiometrically detect intracellular glutathione by significantly enhancing the green emission of the conjugated CdSQDs. Likewise, the ratiometric sensing of solution alkalinity and tris(2-carboxyethyl)phosphine can be achieved using blue-emitted diTyr residues and red-emitted AuNCs as the responsive units, respectively, and the corresponding other two fluorophores as the reference signals. This study addresses a concept of trinity fluorescence ratiometric sensing system with multiple targets and optional references, which should be a promising pathway to meet the challenges from complexing biochemical environments and multivariate analysis.

We reported new findings, i.e., stimuli-responsivity, on the oligomer shell of aggregation-induced emission (AIE) type silver nanoclusters via thiol-induced chemical etching. The intriguing AIE properties of the lipoic acid-protected silver nanoclusters were initially determined with their large Stokes shift, microsecond-scale lifetime and a high content of Ag(I) components. Additionally, likely owing to shell-provided protection, they exhibited desired aqueous storage stability (over 3 months). By modulating solution pH and salinity, the oligomer shell rigidified/softened, resulting in enhancement/quenching of the AIE-based photoluminescence of the silver nanoclusters, accordingly. However, their featured UV–vis absorption remained relatively intact, demonstrating that the changes in photoluminescence are attributed to the transition of radiative and non-radiative energy of the silver nanoclusters. Interestingly, by protonation at low solution pH and electrostatic shield at high salinity, the shrunk shell suppressed the well-established cysteamine-induced etching of the silver nanoclusters, significantly inhibiting the quenching of emission and the bleaching of absorption induced by cysteamine. Such unique stimuli-responsive shell also could serve as a selective window, which could prevent larger size and negatively charged etchants, e.g., glutathione and cysteine, to access and etch the Ag(0) core. Based on this finding, a novel luminescent sensor for cysteamine using the AIE-type silver nanoclusters was then developed with three more advantages. First, owing to relatively active metallic Ag, etching reaction could be fully completed with minutes at ambient condition. Second, specific thiol-Ag interactions also provided superior selectivity for cysteamine over the other 19 natural amino acids (nonthiol-containing) and ascorbic acid. Third, due to high affinity of thiol-Ag interactions, the sensor was endowed with high sensitivity for cysteamine detection with a detection of limit of 15.7 nM. This study not only depicts a new design strategy for other AIE-type metal nanoclusters in sensing applications, but also provides an effective and facile method for understanding structural details of ultrasmall core-shell metal nanoclusters.

Manganese dioxide (MnO

A new kind of luminescent hybrid materials based on ultrasmall nanomaterials, that is, gold nanoclusters (AuNCs) and goose feathers, precious gifts from nature, has been successfully synthesized. Goose feathers possess high specific surface area due to their hierarchical structure and are mainly composed of thiol-rich proteins, for example, keratin, which can reduce Au(III) and encapsulate the formed AuNCs in a large scale. The resultant golden feathers exhibit bright red luminescence under UV light, of which the substructures, that is, barbs and barbules, have been sufficiently stained with red-emitting AuNCs. Furthermore, the AuNC-stained feathers maintain almost unchanged structure (solid and hierarchical) and intact chemical composition. The features of such AuNC/feather hybrids, for example, bulk, high specific surface, inspired us to develop a facile method to prepare various valuable debris from AuNC-based etching, that is, Au(I) complexes with aggregation-induced emission (AIE). We selected tris(2...

Highly sensitive detection of 4-nitrophenol (4-NP), one of the most hazardous and toxic phenols, has been highly sought-after. In this study, we found that 4-NP could selectively quench the 410 nm emission of the dityrosine (diTyr) residues of BSA-protected gold nanoclusters (GNCs@BSA) rather than the conventional red emission of GNCs@BSA via the inner filter effect (IFE). This finding helped us to develop a label-free and separation-free ratiometric fluorescence method for sensing of 4-NP with red emissive GNCs as the endogenous reference for the first time. This ratiometric sensor exhibited rapid response to 4-NP within 1 min. The photoluminescence (PL) intensity ratio of the 410 nm emission of the diTyr residues to the 630 nm emission of the GNCs (F410/F630) showed a linear relationship with 4-NP concentration in the range of 50 to 5000 nM (R2 = 0.991) with a limit of detection (LOD) (S/N = 3) of 13.8 nM (1.9 ng mL−1), remarkably lower than the concentration limit released by the US Environmental Protection Agency (EPA) for drinking water (60 ng mL−1). Also, the ratiometric sensor showed selectivity for 4-NP over other eight common phenol derivatives. Furthermore, the ratiometric sensor was applied to analyze the trace 4-NP spiked in the tap and river water samples and the satisfied results were acquired, showing promising potential of the ratiometric sensor for practical applications.

From the difficulty of awareness of abnormal concentrations of biochemical indexes in people's daily life come wearable sensing technologies. Recently, luminescent wearable biosensors are emerging with simple fabrication, easy use, cost-effectivity and reliability. But several challenges should be taken up, such as availability of varied analytes, high sensitivity, stability of enzymes, photostability, low signal noises and recyclability of sensors. Here, the Luminescent Wearable Sweat Tape (LWST) biosensor is developed via embedding multi-component nanoprobes onto microwell-patterned paper substrates of hollowed-out double-side tapes. The nanoprobes consist of responsive luminophores, enzyme-loaded gold nanocluster (AuNCs) nano-networks, which are wrapped by the switch, MnO2 nanosheets. The responsive luminophores are constructed by 3 substitutable components: enzymes (uricase, GOx and alcohol dehydrogenase) for molecular target recognition, glutathione-protected AuNCs (yellow, red and green) for luminescent signal output and polycations PAH for integration. MnO2 NSs as the switch can quench the emission of the AuNCs but degraded by the reductive product of incorporated enzymes. Thus, targeting analysts (uric acid, glucose and alcohol) can be dose-dependently detected through “turn-on” luminescence approach. After incorporating the nanoprobes into hollow-out tapes, the formed LWST biosensors can detect uric acid, glucose and alcohol in sweat with the help of a smartphone. Subsequently, we primarily apply them into human daily life scenario, sampling from dine parties, and the positive relationships of analyte intakes and the increase of analytes in sweat are significant with individual difference.

Digital light processing (DLP) is currently a cutting-edge technology for desktop projection optical engines. Due to the passive luminescence characteristics, the DLP projection engine needs a few specific illumination optical components for light collimation, homogenization, and color combination, together with a projection lens matching the DLP chip and magnifying the image. In this paper, we propose a design approach that first splits the DLP projection optical engine into individual components for separate design, and then integrates them into a whole system for further verification. For the first step, the collimating lens group is designed for light collection, and the dichroic mirrors are used to fold the light path based on tri-color LED light sources. For the second step, a fly-eye lens and the corresponding relay lens group are designed to achieve uniform illumination on the DMD chip. The third step is to optimize the projection lens group for high-resolution projection display. Based on the design and simulation, the optical efficiency is 63.4% and the uniformity reaches 94.9% on the projection screen. The modulation transfer function (MTF) of the projection lens is higher than 0.4 at 66 lines for the distance of 500 ∼ 1500 m m , and the distortion is lower than 1%. Simulation results show that the total luminous flux is estimated to reach 224.15 lm when the powers of tri-color LEDs are 21 W, 15.5 W, and 25 W, respectively. A projector prototype is built and tested for further verification, which provides a luminous flux of 220.43 lm and uniformity of 90.22%, respectively. The proposed design, demonstrated by both simulation and experiment, exhibits high feasibility and application potential in state-of-the-art commercial projector design.

Manganese dioxide (MnO2) with small size is competent in sensing applications, but its synthesis generally adopts templates or in complex ways. Inkjet printing technique with excellent performance offers a versatile tool due to its stability, flexibility, economy. Herein, an inkjet printing method was developed for rapid synthesis of ultra-small MnO2 nanosheets. The findings validated the feasibility of inkjet printing method for MnO2 nanosheets synthesis and achieved the demand of small size and facile mode. Additionally, the limit of detection (LOD) of ultra-small MnO2 nanosheets in glutathione (GSH) sensing achieved 0.26 μM, which was about 40% more sensitive than that of the typical MnO2 nanosheets, enabling the establishment of a rapid and efficient modality for sensitive and selective GSH sensing. By virtue of the inkjet printing approach, the ultra-small MnO2 nanosheets was obtained in a short time without complicated fabricating process. It can be foreseen that the proposed inkjet printing approach would facilitate the application prospects of ultra-small MnO2 nanosheets in diverse fields. Such a facile approach may open new avenues for synthesis of ultra-small or ultrafine nanomaterials.

With the rapid development of Chinese national economy, the number of car ownership in China increases sharply in last decades. More recently, as a consequence, a large number of end-of-life vehicles (ELVs) emerge. To meet the demands of environmental protection and cycling economy implementation, the development of ELV recycling industry is of primary importance and great urgency. In this context, we have performed the construction and investment analysis of ELV disassembly plant in China, on the basis of a typical case study. To match up the current ELV recycling industry in China, a new ELV disassembly process, with destructive disassembly and non-destructive one combined, was proposed and illustrated in detail. Building on the comprehensive subitems analysis, the investment and economic benefit were decomposed and calculated. The goal of this study is to develop a suitable ELV disassembly sequence for Chinese ELV disassembly industry and provide a beneficial reference for the investment of ELV recycling business. It represents a substantial innovation and will advance the development level of China’s ELV recycling industry.

Dimethylnitrosamine (DMN) is a potent hepatotoxin, carcinogen, and mutagen. In our previous study, a candidate gallic acid (GA) that widely exists in food and fruit was selected for its capability to alleviate DMN toxicity in vivo. We aimed to investigate the therapeutic potential of GA against DMN-induced liver fibrosis. During the first four weeks, DMN was administered to rats via intraperitoneal injection every other day, except the control group. GA or silymarin was given to rats by gavage once daily from the second to the sixth week. GA significantly reduced liver damage in serum parameters and improved the antioxidant capacity in liver and kidney tissues. Cytokines involved in liver fibrosis were measured at transcriptional and translational levels. These results indicate that GA exhibits robust antioxidant and antifibrosis effects and may be an effective candidate natural medicine for liver fibrosis treatment.

The present study examined the role of cystathionine γ-lyase (CSE) in carbon tetrachloride (CClA CSE gene knock-out and luciferase gene knock-in (KI) mouse model was constructed to study the function of CSE and to trace its expression in living status. CClHere, a CSE knock-out and luciferase KI mouse model was established for the first time to study the transcriptional regulation of CSE expression in real time in a non-invasive manner, providing information on the effects and potential mechanisms of CSE on CClCSE deficiency increases pro-inflammatory cytokines in the liver and exacerbates acute hepatitis and liver fibrosis by reducing H

Oligoether carbonates R(PO)nOCO2(PO)nR, where R = Me, Et, or H, PO = propylene oxide ring-opened unit, and n = 1, 2, 3, 4, ∼10, and ∼30, have been prepared and characterized by ESI/MS or MALDI/MS a...