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A 72-kDa matrix metalloproteinase (MMP; sMP) was purified from silver carp skeletal muscle by 30–70% ammonium sulfate fractionation and chromatography. The sMP revealed high gelatinolytic activity from 30 to 60 °C and showed an optimal pH of 8.0. The gelatin-hydrolyzing activity of sMP was inhibited by ethylenediaminetetraacetic acid (EDTA), dithiothreitol (DTT), l -Cys, and l -His. Ca 2+ enhanced the proteinase activity, while a higher concentration of Zn 2+ inhibited this activity. Peptide mass fingerprinting revealed that 14 fragments were identical to MMP-2 from grass carp ( Ctenopharyngodon idella ). The full length of the cDNA sequence encoding sMP was 3005 bps, with an open reading frame (ORF) of 1977 bps encoding 658 amino acid residues. Further, sMP could effectively hydrolyze type I collagen even at 4 °C; its activity remained steady during the entire storage period at 4 °C. These results indicated that sMP is MMP-2 and may have been involved in the protein degradation of fish muscle during the postmortem stage. [ABSTRACT FROM AUTHOR]

An actinyl peroxide cage cluster, Li48+ mK12(OH) m[UO2(O2)(OH)]60 (H2O) n ( m≈20 and n≈310; U60), discriminates precisely between Na+ and K+ ions when heated to certain temperatures, a most essential feature for K+ selective filters. The U60 clusters demonstrate several other features in common with K+ ion channels, including passive transport of K+ ions, a high flux rate, and the dehydration of U60 and K+ ions. These qualities make U60 (a pure inorganic cluster) a promising ion channel mimic in an aqueous environment. Laser light scattering (LLS) and isothermal titration calorimetry (ITC) studies revealed that the tailorable ion selectivity of U60 clusters is a result of the thermal responsiveness of the U60 hydration shells. [ABSTRACT FROM AUTHOR]

An actinyl peroxide cage cluster, Li48+ mK12(OH) m[UO2(O2)(OH)]60 (H2O) n ( m≈20 and n≈310; U60), discriminates precisely between Na+ and K+ ions when heated to certain temperatures, a most essential feature for K+ selective filters. The U60 clusters demonstrate several other features in common with K+ ion channels, including passive transport of K+ ions, a high flux rate, and the dehydration of U60 and K+ ions. These qualities make U60 (a pure inorganic cluster) a promising ion channel mimic in an aqueous environment. Laser light scattering (LLS) and isothermal titration calorimetry (ITC) studies revealed that the tailorable ion selectivity of U60 clusters is a result of the thermal responsiveness of the U60 hydration shells. [ABSTRACT FROM AUTHOR]

• A novel A1-D-A2 type photocatalyst is designed for H 2 O 2 evolution. • The photocatalytic H 2 O 2 evolution activity is obviously enhanced. • Asymmetric receptor units induced efficient charge separation. • Dual reduction sites are confirmed to promote O 2 reduction to H 2 O 2. The study of hydrogen peroxide production by O 2 reduction reaction using covalent organic framework (COF) photocatalysts has attracted extensive attention in recent years. However, there are still great challenges in accurately controlling their structures to achieve rapid carrier separation and efficient O 2 reduction. Based on this, we constructed the A1-D-A2 COF photocatalytic material (TT-DTDA-COF) with asymmetric dual acceptor sites by connecting thieno [3,2-b] thiophene, benzene, and triazine as the basic units through imine bonds. Under the synergistic effect of thieno [3,2-b] thiophene and triazine electron acceptors, the separation and transfer efficiency of TT-DTDA-COF photogenerated carriers was significantly enhanced. At the same time, according to the in-situ infrared and DFT calculation results, it was found that these two acceptor units served as O 2 reduction sites, which realized the multi-site adsorption reduction of O 2 , and effectively enhanced the efficiency of photocatalytic O 2 reduction to H 2 O 2. The experimental results showed that the H 2 O 2 generation rate of TT-DTDA-COF with A1-D-A2 dual receptor structure was 1302 μmol·g−1·h−1 under visible light irradiation, which was 3.4 times higher than that of TB-DTDA-COF with single receptor D-A structure and higher than that of most of the materials reported so far. This study provides a new idea for accurately designing COF-based photocatalysts to achieve efficient O 2 reduction to produce H 2 O 2. [ABSTRACT FROM AUTHOR]

The emergence of carbon dots has broadened the design and application of new room-temperature phosphorescence materials, but the mass production of long-lived color-tunable carbon dots-based phosphorescence materials (CDPMs) is still hindered by solvent dependence and time-consuming. In this work, a minute-level solid-phase synthesis strategy was proposed for the preparation of a series of CDPMs through pyrolyzing the mixture of boric acid and pimelic acid. By tuning the mass ratio of boric acid and pimelic acid, CDPMs with different room-temperature phosphorescence characterises can be obtained within 7 min. Preferably, the CDPMs-60 synthesized from the mass ratio of boric acid and pimelic acid of 60:1 exhibits a long afterglow length up to 10 s and has obvious phosphorescence chromatic aberrations following excitation at 254 and 365 nm, and phosphorescence lifetimes of CDPMs-60 in the blue and green band can reach 1030 ms and 555 ms, respectively. The CDPMs were further successfully applied for the information encryption and fabricating light emitting diodes based on their simple synthesis process, exceptional optical properties and low-toxicity. This study may provide a valuable reference for the facile synthesis and suitable commercial application of room temperature phosphorescence materials. • Solid phase synthesis strategy was designed for the facile syntheses of CDPMs. • Fluorescent/phosphorescent color of CDPMs can be tuned easily in single system. • Effective information encryption was realized by using developed CDPMs. • The CDPMs was successfully applied for the fabrication of LEDs device. [ABSTRACT FROM AUTHOR]

Although it is one of the promising candidates for pseudocapacitance materials, Ni(OH)2 is confronted with poor specific capacitance and inferior cycling stability. The design and construction of three-dimensional (3D) nanosphere structures turns out to be a valid strategy to combat these disadvantages and has attracted tremendous attention. In this paper, a 3D α-Ni(OH)2 nanosphere is prepared via a facile and template-free dynamic refluxing approach. Significantly, the α-Ni(OH)2 nanosphere possesses a high specific surface area (119.4 m2/g) and an abundant porous structure. In addition, the as-obtained α-Ni(OH)2 electrodes are investigated by electrochemical measurements, which exhibit a high specific capacitance of 1243 F/g at 1 A/g in 6 M KOH electrolyte and an acceptable capacitive retention of 40.0% after 1500 charge/discharge cycles at 10 A/g, which can be attributed to the sphere's unique nanostructure. Furthermore, the as-assembled Ni(OH)2-36//AC asymmetric supercapacitor (ASC) yields a remarkable energy density of 26.50 Wh/kg, with a power density of 0.82 kW/kg. Notably, two ASCs in series can light a 2.5 V red lamp sustainably for more than 60 min, as well as power an LED band with a rated power of 25 W. Hence, this 3D α-Ni(OH)2 nanosphere may raise great potential applications for next-generation energy storage devices. [ABSTRACT FROM AUTHOR]

S-nitrosothiols (RSNO) as the potential nitric oxide (NO) storage, transfer and delivery vehicles under physiological condition have been identified as important in a number of disease states. However, a detection and quantification of RSNO method with simple and sensitive in biological media is currently lacking. A novel electrochemical sensing platform based on ionic liquid (IL) and copper porphyrin (PorCu) decorated cuprous oxide (Cu 2 O) nanocomposites was developed to detect RSNO under physiological condition. In this system, RSNO were decomposed by Cu(I) in IL/PorCu/Cu 2 O to release NO, following the generated NO could be oxidized on the electrode to generate current signal. By taking advantage of the synergetic effect of IL, PorCu and Cu 2 O, the sensor exhibited excellent sensitivity and linearity toward various RSNO species in phosphate buffer solution (PBS), pH 7.4. A low detection limit for N-Acetyl-3-(nitrososulfanyl)valine (SNAP), S-nitrosocysteine (CysNO) and S-nitrosoglutathione (GSNO) was 110 nM, 20 nM and 67 nM (S/N = 3), respectively. Furthermore, this method displayed good selectivity, which could be used in complex application. The detection scheme with the features of high sensitivity and ease of operation, implies the potential of IL/PorCu/Cu 2 O for further various complex physiological studies. A novel electrochemical sensing platform based on porphyrin decorated Cu 2 O as nano-catalyst and electrode material was developed for sensitive S-Nitrosothiols detection under physiological pH. [Display omitted] • A electrochemical biosensor based on ionic liquid and porphyrin modified Cu 2 O (IL/PorCu/Cu 2 O) as nanocrystals was designed. • The IL/PorCu/Cu 2 O composite has high catalytic activity toward RSNO. • By taking advantage of the synergy of IL, PorCu and Cu 2 O, the sensor exhibited excellent sensitivity and selectivity. • The method could be used in complex matrix. • The sensor showed good performance. [ABSTRACT FROM AUTHOR]

S‐Nitrosothiols (RSNOs) which are important intermediates in circulating reservoirs of nitric oxide (NO), transport and numerous NO signaling pathways play intricate roles in the etiology of several pathologies. However, it is still a challenge to control the release of NO from nitrosylated compounds under physiological pH. In this paper, for the first time, we report the catalytic activity and kinetic study for the modulation of NO release from RSNOs by an array of metal‐organic frameworks (MOFs) (M‐MOF (M′); M=Zr, Cu; and M′=Cu, Pd, no metal) under physiological conditions via time‐dependent absorbance spectra. The result showed that metal active sites as well as the morphology and pore size of MOFs exhibited different activities toward RSNOs. The order of catalytic activity of these MOFs toward RSNOs is ordered in the decreasing sequence: Cu‐MOF(Pd)>Cu‐MOF(Cu)>Cu‐MOF(no metal)>Zr‐MOF(Pd)>Zr‐MOF(Cu)>Zr‐MOF(no metal). In addition, Zr‐MOF(Pd) was as model for cell experiment, demonstrated Zr‐MOF(Pd) could react with RSNOs to generate NO in the complex environment of cell. Collectively, these findings establish a platform for MOFs‐based, highly catalyze RSNOs in biological samples, a powerful tool for expanding the knowledge of the biology and chemistry of NO‐mediated phenomena. [ABSTRACT FROM AUTHOR]

Identifying defects/traps is of vital importance for the implementation of high-performance Ga2O3 power devices. In this work, majority and minority carrier traps in beta-gallium oxide ($\beta $ -Ga2O3) have been investigated and identified by means of deep level transient spectroscopy (DLTS) in Ni/ $\beta $ -Ga2O3 Schottky barrier diode (SBD) and NiO/ $\beta $ -Ga2O3 p+-n heterojunction diode (HJD). For both diodes, a dominant energy level of majority carrier (electron) trap states is determined to be ${E}_{C}-$ (0.75–0.79) eV with a concentration of (2.4–4.1) $\times 10^{{13}}$ cm $^{-{3}}$. Meanwhile, an additional trapping level at ${E}_{V} +0.14$ eV with a concentration of 1.2 $\times 10^{{14}}$ cm $^{-{3}}$ yield is present in NiO/ $\beta $ -Ga2O3 bipolar HJD but absent in the Ni/ $\beta $ -Ga2O3 SBD unipolar counterpart. The detection of such minority carrier traps originates from the hole injection through trap-assisted tunneling (TAT) from $\text{p}^{+}$ -NiO to $\beta $ -Ga2O3. The bias- and frequency-dependent DLTS characteristics identify that such shallow-level minority carrier traps are located in the $\beta $ -Ga2O3 bulk region rather not interfacial states at the NiO/ $\beta $ -Ga2O3 heterointerface. The identification of both majority and minority carrier traps in this work may shed light on the in-depth understanding of carrier transport mechanisms in Ga2O3-based unipolar and bipolar power devices. [ABSTRACT FROM AUTHOR]

The low trapping efficiency of photogenerated electrons by the targeted reduction site seriously restricts the kinetics of H 2 O 2 photosynthesis via two-electron oxygen reduction reaction. Here, two polyimide covalent organic frameworks (PT-COF and PB-COF) possessing carbonyl groups with different electron-trapping capacity were elaborately designed. PB-COF with electron-rich carbonyl site presented 4.22 times improvement in H 2 O 2 formation rate up to 2044 μmol g−1 h−1, and exhibited outstanding photostability after 120 h continuous opearting. Meanwhile, solar to-chemical energy efficiency was 0.68%, representing one of advanced polymer based photocatalysts. We demonstrated electronic structure of the carbonyl active center was modulated by tuning electron attraction capability of the donor unit via increased the built-in electric field to accelerate charge separation and directional transfer. The electron-rich carbonyl site is identified to boosted H 2 O 2 photosynthesis activity via reducing the *OOH binding energy. Our work offers a tailoring electron density of pre-designable active site strategy for enhanced solar-to-chemical energy conversion. [Display omitted] • The first imide-linked COF for highly efficient photosynthesis H 2 O 2 from H 2 O and O 2. • Tailoring electron density of pre-designable active center to boost catalytic efficiency. • Electron-rich carbonyl site promotes carrier separation and reduces Gibbs free energy of *OOH intermediate. [ABSTRACT FROM AUTHOR]

• A novel cold-set rice starch (RS)/heat-set curdlan composite gel systems prepared. • The RS-curdlan interaction affects the composite gel's structure and properties. • The 5:5 composite gel starts to show rheological properties dominated by curdlan. • Curdlan inclusion in RS enhances gel structure density and mechanical properties. • A schematic proposed for temperature-induced conformational change. In pursuit of advancing the understanding of composite gel systems, this study delves into the intricate realm of rheology, structural elucidation, and mechanical attributes. Specifically, it scrutinizes the symbiotic interplay between rice starch, a cooling-set gel, and curdlan, a thermo-irreversible heating-set gel. A higher curdlan content enhances the inter-chain hydrogen bonding between rice starch and curdlan, resulting in a denser gel structure and thus increased moduli, solid-like behavior, and mechanical properties, and reduced frequency-dependence, especially at high temperatures (>65 °C). For example, with 50 % curdlan incorporation, G ′ (90 °C) improved by 252 %. Notably, thermal treatment can compromise the structural integrity of the rice starch gel, reducing strength and softening texture. However, this textural degradation can be effectively mitigated with, for example, 30 % curdlan incorporation, resulting in a 55-fold hardness increase at 85 °C. The knowledge gained from this work offers valuable guidance for tailoring starch-based gel products to specific properties. [ABSTRACT FROM AUTHOR]

As a kind of green and high quality feed, fermented feed has the activity of promoting growth and improving immunity in aquaculture. The aim of this study was to develop a new liquid fermented feed for the culture of sea cucumber Apostichopus japonicus and evaluate its nutritional value and function. After the commercial feed of the sea cucumber was fermented by Corynebacterium glutamicum, the contents of crude protein, free amino acids, palmitoleic acid, linoleic acid, arachidonic acid, and the total content of polyunsaturated fatty acids were significantly increased. By feeding the fermented food, the weight gain rate, special growth rate and feed conversion rate of the sea cucumber were significantly increased, and the mortality rate was significantly reduced in the challenge test. The cellulase activity in the gut of the sea cucumber fed with the fermented feed was significantly increased, while the activities of alkaline phosphatase, acid phosphatase, total nitric oxide synthase, catalase, and lysozyme in the coelomic fluid were significantly increased. The fermented feed changed the gut microbiota of the sea cucumber and significantly reduced the relative abundance of Vibrio, which was the main pathogen causing skin ulcer syndrome. Transcriptome analysis revealed 4492 differentially expressed genes that can be enriched in biological processes such as immune system processes and immune responses, and affect the growth performance and immune regulation of the sea cucumber through metabolic pathways such as ribosomal biogenesis. Further gene expression analysis showed that the upregulation of genes such as NFκBI, TLR, TLR3, TRAF6, MyD88, and p38 activated the TLR signaling pathway and enhances the immune response of the sea cucumber. Therefore, C. glutamicum fermented feed can promote the growth of the sea cucumber, enhance non-specific immunity, and resist pathogen infection, making it a highly promising feed for application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chlorogenic acid nanoparticles were incorporated into pullulan/gelatin matrixes. • The transparent film exhibited good ultraviolet-blocking efficiency. • The colorless film also held fluorescent properties for anti-counterfeiting. • The safe films possess both antibacterial and antioxidant activity. Food packaging is innovating towards more environmental-friendly polymers and broader applications of bioactive compounds. In this study, active packaging materials were successfully prepared by incorporating chlorogenic acid (CGA) nanoparticles into pullulan/gelatin polymer matrixes. The rhamnolipid (RL) and/or CGA were combined with chitosan (CS) to synthesize active nanoparticles by the ionic crosslinking method. The film containing CS/RL/CGA nanoparticles (F/CRC) exhibited both ultrahigh visible light (400–760 nm) transmittance (approximately 90%) and UVA (320–400 nm)-blocking efficiency (89.06%). Its fluorescent properties can be used for anti-counterfeiting. Significantly, the bacterial inhibition rates of F/CRC against E. coli and S. aureus were 92.14% and 98.72%. F/CRC also showed good antioxidant capability and biosafety. Finally, the packaging test further indicated that F/CRC could delay the browning of bananas and the bacteria growth of chicken samples. This work presents a green and feasible route to produce functional materials with UV-shielding properties for packaging applications. [ABSTRACT FROM AUTHOR]

In this article, we propose a multiple beams spread-spectrum modulation signal transmitted by a Cassegrain antenna for communication and direction-finding applications. The main idea is that a sum beam and two difference beams are transmitted by the Cassegrain antenna similar to the Monopulse technique. According to the beams’ radiation pattern, a multiple beams spread-spectrum modulation scheme is designed to modulate the beams’ spatial parameters into the transmit signal constellation. In this way, a receiver with a single antenna demodulates the data information and the directional information from the receive signal constellation, simultaneously. Simulation results show that the proposed signal can be applied to the integrated system of communication and direction-finding in a low signal-to-noise ratio environment. [ABSTRACT FROM AUTHOR]

Abstract: We consider paths in the plane with (), (), and ()-steps that start at the origin, end at height , and stay strictly to the left of a given non-decreasing right boundary. We show that if the boundary is periodic and has slope at most , then the ordinary generating function for the number of such paths ending at height n is algebraic. Our argument is in two parts. We use a simple combinatorial decomposition to obtain an Appell relation or “umbral” generating function, in which the power is replaced by a power series of the form where Then we convert (in an explicit way) the umbral generating function to an ordinary generating function by solving a system of linear equations and a polynomial equation. This conversion implies that the ordinary generating function is algebraic. We give several concrete examples, including an alternative way to solve the tennis ball problem. [Copyright &y& Elsevier]

Linking sinuosity, a fairly recently developed metric, with high temperature extremes (HTEs) can be both useful and insightful to better understand the physical mechanisms behind HTEs. However, it is not clear whether there exists a relationship between the sinuosity changes and HTE changes in present and future climate conditions over southeastern China. In this paper, the anomalous characteristics of the atmospheric circulation are quantified by sinuosity. Three sinuosity metrics are used in this study: individual sinuosity (SIN), aggregate sinuosity (ASIN), and comprehensive sinuosity (CSIN). Furthermore, we examine the relationship between sinuosity changes and HTE changes in present and future climate conditions. ASIN is strongly correlated with surface air temperature (SAT). We find that the influence of individual sinuosity (SIN) at different latitudes on the SAT of southeastern China is different. The SIN of low (middle) latitude isohypses has significant positive (negative) correlations with the SAT of southeastern China. The SIN of high-latitude isohypses is rather limited and can therefore be ignored. The projected relationship between the sinuosity changes and HTE changes in the late 21st century suggests similar results. The change in SAT is related to the changes in climate variables over southeastern China in the future, and these changes increase with the increase in Z500 or V850 and the decrease in U500. Moreover, the frequencies of large (small) comprehensive sinuosity (CSIN) values at low (mid) latitudes will increase. At the end of the 21st century, Z500 isohypses at different latitudes will have an obvious poleward shift. Our results indicate that measuring the aggregate waviness of the midtropospheric flow (via sinuosity) can provide insight regarding HTEs, and the climate model output can be used to examine the future likelihood of increased HTE. [ABSTRACT FROM AUTHOR]

A novel sliding mode control combined with extended state observer (ESO) is proposed for an ankle exoskeleton driven by electrical motor. During the process of assisting, it is necessary to design an effective controller for assisting torque of ankle exoskeleton. However, the parameter uncertainty of complex dynamics model and the irregular motion of human ankle may affect the torque control accuracy. For a high control precision of assisting torque when facing the modeling uncertainty, the sliding mode control is employed, but a large switching gain is usually needed in order to suppress the disturbance, which cause the control signal vibrate greatly. ESO can observe and suppress the disturbance and modeling uncertainty, but its tracking performance needs to be improved. Therefore, the proposed complex controller takes the advantages of sliding mode control and extended state observer, which can not only improve torque tracking performance but also overcome the disturbance force caused by the change of human joint angle without increasing chattering of control signal. Experimental studies are carried out to validate the effectiveness of the proposed control. The results show the presented controller have better torque tracking performance and robustness stability, and the proposed controller can reduce the chattering compared with the tradition sliding mode control. [ABSTRACT FROM AUTHOR]

• A prussian blue nanocubes decomposition-assisted competitive sensor was developed. • With the dissolution of the nanocubes, a decreased T -line intensity was obtained. • The proposed sensor was highly sensitive and selective with a low detection limit. • Satisfactory analytical results in real samples suggests the sensor's applicability. A prussian blue nanocubes decomposition-assisted signal amplification strategy for competitive lateral flow immunoassay (PBNCD-SALFIA) was innovatively proposed to analyze aflatoxin B 1 (AFB 1) in foodstuffs. The signal was amplified on account of the PBNCs can degrade and fade under alkaline condition, which could weak the color of the test- and control-lines, thereby improving the sensitivity of the sensor. The strategy was technically-simple, just using NaOH as an amplifier can realize signal amplification in the competition assay. Under optimized conditions, the enhanced strip exhibited excellent specificity and sensitivity in AFB 1 monitoring with a detection limit of 23 pg/mL, which was approximately 4- and 8-folds lower than those of PBNCs-LFIA (90 pg/mL) and conventional gold nanoparticles-LFIA (175 pg/mL), respectively. Taking the advantage of the color-fading, this platform revealing the lowest detectable concentration of 0.184, 0.368 and 0.184 μg/kg for AFB 1 in corn, peanut and pumpkin seed within 58 min, separately, showing reliable results. [ABSTRACT FROM AUTHOR]

The accurate distribution of countercations (Rb+ and Sr2+) around a rigid, spherical, 2.9‐nm size polyoxometalate cluster, {Mo132}42−, is determined by anomalous small‐angle X‐ray scattering. Both Rb+ and Sr2+ ions lead to shorter diffuse lengths for {Mo132} than prediction. Most Rb+ ions are closely associated with {Mo132} by staying near the skeleton of {Mo132} or in the Stern layer, whereas more Sr2+ ions loosely associate with {Mo132} in the diffuse layer. The stronger affinity of Rb+ ions towards {Mo132} than that of Sr2+ ions explains the anomalous lower critical coagulation concentration of {Mo132} with Rb+ compared to Sr2+. The anomalous behavior of {Mo132} can be attributed to majority of negative charges being located at the inner surface of its cavity. The longer anion–cation distance weakens the Coulomb interaction, making the enthalpy change owing to the breakage of hydration layers of cations more important in regulating the counterion–{Mo132} interaction. [ABSTRACT FROM AUTHOR]

The accurate distribution of countercations (Rb+ and Sr2+) around a rigid, spherical, 2.9‐nm size polyoxometalate cluster, {Mo132}42−, is determined by anomalous small‐angle X‐ray scattering. Both Rb+ and Sr2+ ions lead to shorter diffuse lengths for {Mo132} than prediction. Most Rb+ ions are closely associated with {Mo132} by staying near the skeleton of {Mo132} or in the Stern layer, whereas more Sr2+ ions loosely associate with {Mo132} in the diffuse layer. The stronger affinity of Rb+ ions towards {Mo132} than that of Sr2+ ions explains the anomalous lower critical coagulation concentration of {Mo132} with Rb+ compared to Sr2+. The anomalous behavior of {Mo132} can be attributed to majority of negative charges being located at the inner surface of its cavity. The longer anion–cation distance weakens the Coulomb interaction, making the enthalpy change owing to the breakage of hydration layers of cations more important in regulating the counterion–{Mo132} interaction. [ABSTRACT FROM AUTHOR]

There is an increasing demand for monitoring ammonia in livestock farming, which can prevent livestock products from being contaminated by bacteria and viruses. As a prospective material for resistive sensors, polypyrrole (PPy) still suffers from low sensitivity and poor selectivity. Herein, zinc-tetra(p-sulfonylphenyl) porphyrin (Zntpp) particles are anchored on the PPy network by a one-step mild electrodeposition route to form a resistive sensor with the wrinkle-like nanostructure. The optimal PPy/Zntpp (Pzt) sensor demonstrates an outstanding response value of 104.3 % toward ammonia with a response/recovery time of 42/223 s, compared with that of PPy (7.2 % in response and 47/230 s). The durability and stabilities have been explored, and the limit of detection for Pzt is calculated to be ∼8.63 ppm, which enables trace ammonia in livestock farming. Additionally, the sensing mechanism can be attributed to the p-n heterojunction. Furthermore, a wireless sensor device that consists of a Pzt sensory unit, a microcomputer, and a Bluetooth module is assembled, and the concentration information can be read precisely in real-time by a smartphone, indicating the great application prospects in the field of livestock farming. [Display omitted] • Constructure of polypyrrole/zinc-porphyrin for ammonia resistive sensor. • Outstanding sensitivity and selectivity of PPy/Zntpp toward NH 3. • Fabrication of a wireless sensor that display NH 3 concentration on a smartphone. • Great potential application prospects in the field livestock farming. [ABSTRACT FROM AUTHOR]

In this paper, the natural antibacterial agent cinnamaldehyde (CA) was made into nanoemulsions to improve its water solubility. Subsequently, the active gelatin (GL-CA-Vc) films with antibacterial and antioxidant activities were prepared by combining silver carp skin gelatin with CA nanoemulsions and vitamin C (Vc). Compared with the gelatin control (GL-Control) film, the thickness, roughness and water vapor permeability (WVP) of active films increased significantly. In addition, the elongation at break (EAB) and light barrier property of active films were also enhanced. The antibacterial and antioxidant activities of active films were related to the content of active additives. The film containing 100 mg of CA and 50 mg of Vc (GL-100CA-50Vc) had good light barrier property and a high EAB (158.00 ± 12.51%). What's more, the inhibition rate of GL-100CA-50Vc film against Pseudomonas aeruginosa was 55.97 ± 4.25%, and the free radical scavenging rate of the film to ABTS and DPPH was 96.26 ± 0.72% and 95.74 ± 0.20% respectively, which indicated that the film had good antibacterial and antioxidant activities. • Active films were prepared by combining fish gelatin with CA nanoemulsions and Vc. • GL-CA-Vc films possessed good EAB, ultraviolet and visible light barrier capacity. • The prepared active films showed excellent antioxidant and antibacterial activities. [ABSTRACT FROM AUTHOR]

• A sensitive biosensor that introduced MoS 2 as extraordinary probes was constructed to detect tetracycline. • Exfoliated nanosheets with large, middle, and small sizes and all exhibited excellent water-dispersibility and stability. • The versatile MoS 2 can label antibodies without the need for surfactant modification. • A very low limit of detection of 0.023 ng/mL was obtained for tetracycline detection. In this study, we report a simple approach for synthesizing three kinds of molybdenum disulfide (MoS 2) nanosheets with different sizes of large, middle, and small (which are defined as L -MoS 2 , M -MoS 2 and S -MoS 2) by an aqueous-phase exfoliation and differential-zone centrifugation (AE-DC) strategy, and for the first time explored the MoS 2 labeled antibodies (Abs) as probes for sensitive detection of tetracycline (TET) on lateral flow assays (LFAs). The hierarchical MoS 2 had uniform sizes (Average size: 366 ± 65.70 nm, 131 ± 24.39 nm and 55 ± 8.56 nm for L -MoS 2 , M -MoS 2 , and S -MoS 2 , respectively; thickness: 3 nm, 1 nm for and 0.5 nm for L -MoS 2 , M -MoS 2 and S -MoS 2 , respectively), and all exhibited excellent water-dispersibility and stability. Compared with M -MoS 2 and S -MoS 2 based LFAs, L -MoS 2 based LFA particularly displayed highly sensitive detection of TET due to the larger surface area and stronger color intensity. Under optimized experimental conditions, the developed L -MoS 2 -based immunosensor showed a great linear relationship over the range of 0.012–0.75 ng/mL in 15 min and a signal sensitivity up to 0.023 ng/mL for TET detection, which was at least 17-fold lower than traditional gold nanoparticles based LFA. The assay resulted in excellent specificity and reproducibility, and can be well-applied in milk, honey, and beef samples for monitoring TET. [ABSTRACT FROM AUTHOR]

In water treatment, it is a valid way to remove Cu(II) efficiently via layered double hydroxides (LDHs) intercalated with chelate, but the desorption and its mechanism remain an unsolved difficult problem. To solve this problem, MgAl LDHs intercalated with EDTA (MgAl‐EDTA‐LDHs) was synthesized by one‐step co‐precipitation method, and applied to recover Cu2+. The characterizations of SEM, XRD, XPS, EA and AAS were employed, and the results showed that MgAl‐EDTA‐LDHs exhibited a typical lamellar structure, the adsorption capacity of MgAl‐EDTA‐LDHs on Cu2+ could reach 79.69 mg/g, which was attributed to the chelation of EDTA and chemical bonding of hydroxyl (−OH) on the surface of LDHs layers. In addition, the adsorption capacity could achieve 45.75 mg/g after eluting by Na2CO3 solution, which was relevant to the ion exchange by CO32−. Herein, the adsorption and desorption mechanism of MgAl‐EDTA‐LDHs on Cu2+ was expounded, which may pave a new way to recover the heavy metal and provide a theoretical guidance for future research. [ABSTRACT FROM AUTHOR]

Conventional immunochromatographic assays (ICAs) based on gold nanoparticles (GNPs) suffer from the disadvantage of low sensitivity. In this work, a highly sensitive ICA based on polydopamine coated zirconium metal-organic frameworks labeled antibodies (ZrPA-Ab) as a novel probe was developed for visual determination of deoxynivalenol (DON). The ZrPA was synthesized via an oxidative self-polymerized assembly (OPMA) strategy using porphyrin functionalized zirconium metal-organic frameworks (Zr-MOFs, MOF-525) and polydopamine (PDA). The Abs could directly attach to the ZrPA surface owing to the large specific surface area, excellent water-stability and bio-compatibility of the ZrPA, on this basis, a sensitive, precise and reliable immunoassay method can be developed for rapid and selective detection of DON. Under optimized conditions, a non-linear calibration curve was obtained in the range of 0–50 ng/mL DON concentration with an IC 50 of 1.22 ng/mL, and the visual detection limit was 0.18 ng/mL, which was about 8-times more sensitive than that of the conventional GNPs-based ICA. Finally, the proposed ZrPA-ICA was successfully applied for the detection of DON in pig hind legs meat, green bean, maize and millet samples, revealing the feasible and reliable application of this biosensor in different food matrices. Thus, this work broadens the possibilities for the use of MOFs as a novel labeling carrier in immunoassays. Image 1 • A Zr-MOFs-polydopamine (ZrPA) based sensor was employed for deoxynivalenol detection. • The ZrPA shares the merits of excellent water-stability and water-dispersibility. • This assay has an 8-fold improved sensitivity than gold nanoparticles (GNPs)-sensor. • The approach exhibited high selectivity and excellent food sample application ability. • This work expands the application of MOFs as a novel label in immunoassays. [ABSTRACT FROM AUTHOR]

• A microorganism@AuNPs based immunosensor was constructed for ochratoxin A detection. • The probe was fabricated by reacting microorganism with HAuCl 4 via biosorption and bioreduction. • Assay performance of this novel biosensor was 8-fold improved for OTA detection. • The approach exhibited high selectivity and real food sample testing. A simple and novel immunochromatographic assay (ICA) was developed for specific and sensitive determination of ochratoxin A (OTA) employing microorganism (MO) as reducers and carriers. In this work, microorganism loaded gold nanoparticles (MO@AuNPs) composites were synthesized by reacting Yeast/Lactobacillus (LAB) with HAuCl 4 via biosorption and subsequent bioreduction. The synthesis conditions (pH and reaction time) and main parameters (morphology, diameter and functional groups) of MO@AuNPs were investigated. Owing to the large sizes (about 2 μm) and high adsorption abilities of MO@AuNPs, the few antibodies were labeled, resulting a lower detection limit for ICA. After optimization, the linear detection of OTA using MO@AuNPs-based immunoassay ranged from 0.1 to 1.6 ng/mL, and the visual limit of detection (vLOD) was 0.1 ng/mL, which was nearly 8-fold lower than traditional AuNPs-ICA. Meanwhile, the proposed strategy also possessed high specificity for OTA against other mycotoxins. The applicability of the platform was successfully assessed through the detection of OTA in rice, corn, ginger and green bean samples. The results indicated that these creative sensing elements are promising alternatives and bring an innovative inspiration for biological detections. [ABSTRACT FROM AUTHOR]

• A novel, sensitive, and stable fluorescent sensor was developed for TET detection. • The synthesized MoS 2 NPs possessed superior solubility and strong blue fluorescence. • A low detection limit of 0.032 μM with good linear relationship was achieved. • This prominent technique could be applied in milk and bovine muscle samples. The wide use of tetracyclines (TCs) for prevention and therapy of animal diseases may result in excessive residues in animal products, which could pose serious risks to human health. A novel molybdenum disulfide nanoplates (MoS 2 NPs)-based fluorescent sensor for tetracycline (TET) is reported. The MoS 2 NPs, synthesized via a facile bottom-up hydrothermal route, showed blue fluorescence at 430 nm in aqueous solution. Interestingly, its fluorescence was quenched significantly upon addition of TET, which is mainly due to a combination of the inner filter effect and electron transfer. Thus, the MoS 2 NPs based fluorescence sensor was delineated for the detection of TET. The methodology here presented showed a low detection limit of 0.032 μM and satisfied recoveries from 88.46% to 108.62% in spiked milk, milk powder and bovine muscle samples. [ABSTRACT FROM AUTHOR]

In this work, the cinnamaldehyde (CA) loaded nanoparticles were synthesized by directly cross‐linking chitosan hydrochloride (CSH) and sulfobutyl ether‐β‐cyclodextrin (SBE‐β‐CD). The CA/SBE‐β‐CD inclusion complex was firstly prepared, and its highest encapsulation efficiency (EE) was 86.34%. Field Emission Scanning Electron Microscope results indicated that the inclusion complex showed massive aggregates with a coarse and fluffy texture and irregular surface. Then, the inclusion complex interacted with CSH to form nanoparticles. The EE of CA in nanoparticles was improved. Atomic force microscopy showed the nanoparticles had regular and spherical morphology. Fourier transform infrared spectroscopy analysis demonstrated that CA was mainly encapsulated in the inner place of CSH/SBE‐β‐CD nanoparticles (CSNs). The enhanced thermal stability of the nanoparticles was found in differential scanning calorimeter. X‐ray diffraction implied that CA‐CSNs existed in the amorphous state. CA‐CSNs had excellent slow release property. Further, the bacteriostatic effect of CA‐CSNs was much better than that of CA and CSNs. All the results indicated that CSNs can be used as a promising carrier to encapsulate CA. Practical applications: CA is an effective antimicrobial and generally recognized as Safe‐GRAS. CA also exhibits many other bioactivities and has been commonly used for digestive, cardiovascular and immune system diseases. However, CA is easy to be oxidized and volatilized during storage for poor water solubility. The nanoencapsulations display the capacities of enhancing solubility of bioactive compounds, protecting them from degradation, and prolonging their residence. In this manuscript, CA loaded nanoparticles were investigated. The results suggested that the nanoencapsulation could benefit for improving water solubility and stability of CA. This strategy could be helpful for its application and development in food preservation. [ABSTRACT FROM AUTHOR]

Developing a facile method to fabricate new heterogeneous Metal-Organic Framework (MOFs) based catalysts with high catalytic activity and stability has drawn significant attention. Herein, we demonstrate a simple in-situ pyrolysis reduction strategy to fabricate a novel three-dimensional (3D) Cu-based catalyst, which displays an outstanding performance for the decomposition of 4-nitrophenol (4-NP). Detailed characterization including SEM, FTIR, XPS, ICP-OES, HRTEM, SAED, XRD and BET confirmed the formation of the Cu/C porous composites (Cu/C-PC). Taking advantage of enormous Cu particles in the composite as well as ultrahigh surface area (196.7 m2/g) of carbon support, Cu/C-PC presents prominent catalytic activity for the hydrogenation reduction 4-NP to 4-aminophenol (4-AP) with apparent rate constant (K app) of 0.0267 s−1 (the ratio of K app to the catalyst amount is 119 s−1 g−1), which is dramatically higher than that previous reports. On the contrary, after being washed successively (Cu/C-PC-AW) by FeCl 3 , HCl aqueous solution and deionized water, the Cu/C porous composite materials exhibit fairly weak catalytic activity. The catalytic performance of Cu/C-PC is better than Cu, Cu 2 O and CuO nanoparticles as well as other catalysts in previous reports. Furthermore, Cu/C-PC shows excellent reusability, indicating its potential applications in treatment of water pollution. [ABSTRACT FROM AUTHOR]

The uncertainty of renewable energy has brought challenges to the real-time dispatch of integrated energy systems (IES). Nowadays, reinforcement learning (RL) is widely used in IES real-time dispatch to deal with the uncertainty of renewable energy. However, traditional RL algorithms often face the problem of dimensionality when there are numerous controllable units in the system, which will increase operating costs and training time significantly. Based on the above issues, we developed a novel real-time dispatch method for IES with RL model training in stages based on the dueling double deep quality network (D3QN). Dispatches of different controllable units in IES are decomposed into a multi-stage training process according to the degree of thermoelectric coupling and the complexity of equipment operation. This makes the action space of each training stage independent, alleviating the problem of extra-large action space in the traditional RL method. In addition, an improved action-choosing strategy is proposed to enhance local optimization in the process of algorithm training by introducing "offset" according to probability in the training progress. The simulations were carried out on four different types of days in an IES. The results show that the proposed method can effectively reduce operating costs and accelerate convergence. • A multi-stage real-time dispatch method for IES based on RL is proposed. • Number of actions in action space is reduced without increasing discrete interval. • An improved action-choosing strategy is proposed to speed up the convergence rate. • Fixed strategies for units are proposed to participate in the training process. • The effect of the method is evaluated through operating costs and convergence rate. [ABSTRACT FROM AUTHOR]

Extreme precipitation has often occurred in Southeastern China, while the possible mechanism is not clear. In order to bridge the scale gap between large-scale circulation and extreme precipitation, in this paper, the k-means clustering technique—a common method of weather-type (WT) analysis—was applied to regional 850-hPa wind fields. The reasonable determination of k values can make the later WT analyses more reliable. Thus, the Davies–Bouldin (BD) criterion index is used in the clustering process, and the optimal value of the k was determined. Then, we obtain and analyze the frequency, persistence, and progression of WTs. The rule of transitions from one WT to another may help explain some of the physical processes in winter. We found a special evolutionary chain (WT3→WT1→WT2→WT5→WT3) that can be used to explain the cold wave weather process in winter. Different WTs in the evolutionary chain correspond well to different stages of the cold wave weather process (gestation (WT3), outbreak (WT1), eastward withdrawal (WT2), and extinction (WT5)). In addition, we found that there are obvious differences in precipitation between December and February. After reassembling five kinds of WTs, two modes are formed: dry WTs and wet WTs. Our research shows that the intraseasonal variation of precipitation can be attributed to the fluctuation between the wet and dry WTs, and the different phases of teleconnection can correspond well with it. For example, the relative frequencies of wet WTs are higher in February. These WTs correspond to the positive phase of the WP and ENSO, the negative phase of the EA and EU, and the strong MJO state of the second, third, and eighth phase. Our work has well established the relationship between synoptic scale and large-scale circulation, which provides a reference for climate model simulation and future climate prediction. [ABSTRACT FROM AUTHOR]

Herein, a three‐dimensional (3D) mesoporous straw‐like Co3O4 was prepared via a simple hydrothermal synthesis with cobalt acetate as the cobalt source and p‐phthalic acid as the precipitator. The straw‐like Co3O4 comprises lots of superposed nanosheets with thicknesses of 100–150 nm. Co3O4 nanosheets are assembled with irregular nanoparticles and there are a number of holes in the interior of nanosheets. When employed as an anode for rechargeable Li‐ion batteries, 3D mesoporous straw‐like Co3O4 indicates superior electrochemical activities. The discharge specific capacity maintains in about 1194 mAh g−1 after 100 cycles at 400 mA g−1. This straw‐like Co3O4 also delivers a high capacity of 956 mAh g−1 after 60 cycles at 800 mA g−1. The capacitive and diffusion behaviors are responsible for the superior Li+ storage of 3D mesoporous straw‐like Co3O4. The facile synthesis method and good electrochemical performances make the 3D mesoporous straw‐like Co3O4 a good candidate with enhanced electrochemical performance for Li‐ion batteries. [ABSTRACT FROM AUTHOR]

Studying numerous biologically important species simultaneously is crucial to understanding cellular functions and the root causes of related diseases. Direct visualization of endogenous biothiols in biological systems is of great value to understanding their biological roles. Herein, a novel multi‐signal fluorescent probe was rationally designed and exploited for the simultaneous sensing of homocysteine (Hcy), cysteine (Cys), and glutathione (GSH) using different emission channels. This probe was successfully applied to the simultaneous discrimination between and visualization of endogenous Hcy, Cys, GSH, and their transformation in living cells. Multitasking: A multi‐signal fluorescent probe was exploited for simultaneously differentiating between and sensing of endogenous homocysteine, cysteine, glutathione, and their transformation in living cells. [ABSTRACT FROM AUTHOR]

Studying numerous biologically important species simultaneously is crucial to understanding cellular functions and the root causes of related diseases. Direct visualization of endogenous biothiols in biological systems is of great value to understanding their biological roles. Herein, a novel multi‐signal fluorescent probe was rationally designed and exploited for the simultaneous sensing of homocysteine (Hcy), cysteine (Cys), and glutathione (GSH) using different emission channels. This probe was successfully applied to the simultaneous discrimination between and visualization of endogenous Hcy, Cys, GSH, and their transformation in living cells. [ABSTRACT FROM AUTHOR]

We demonstrate a unique negative solvatochromic emission (NSE) process from a conformational change of a coordination cage in response to solvent composition. The cationic cage contains two tetra-(4-pyridylphenyl)ethylene (TPPE) luminogens on two opposite faces, linked by Pt(PEt3)2 and isophthalate. When the solvent changes from acetone/acetonitrile/methanol to water, the emission of single cages gradually shifts to short wavelength (NSE) with a drastic value of ∼60 nm. Small angle X-ray scattering (SAXS) measurements indicate a molecular conformational change during the process and intramolecular π–π stacking and hydrophobic interaction between the TPPE planes could be the driving forces. As a comparison, a cage with a longer inter-fluorophore distance does not have such strong intramolecular interactions and only shows regular positive solvatochromic emission (PSE) under the same conditions. [ABSTRACT FROM AUTHOR]

Circular RNA (circRNA) is a class of endogenous non-coding RNA, a type of single-stranded covalently closed RNA molecule formed by alternative splicing of exons or introns. Previous studies have demonstrated that circRNA participates in modulating biological processes such as cell proliferation, differentiation and apoptosis, and plays key roles in tumor occurrence and development. CircRNA nuclear receptor interacting protein 1 (circ_NRIP1), a form of circRNA, is abnormally expressed in certain human tumor types. It is present at a higher abundance compared with cognate linear transcripts and can regulate malignant biological behaviors such as tumor proliferation, invasion and migration, revealing a currently unexplored frontier in cancer progression. The present review presents a pattern of circ_NRIP1 expression in various malignant tumor types and highlights its significance in cancer development, in addition to its potential as a disease indicator or future therapeutic agent. [ABSTRACT FROM AUTHOR]

We investigated Salmonella contamination in a slaughterhouse in Jiangsu province (China) by analysing prevalences, loads, and serotypes of Salmonella isolates. In total, 480 samples were collected, with total prevalence of 25.4%. High Salmonella prevalence and load were observed at exsanguination and splitting stages (40.6% and 75.0%; 2.50 ± 0.94 and 2.24 ± 0.72 logMPN/m 2 , respectively), with low prevalence and load at dehairing, flaming, and chilling stages (2.5%, 5.0%, and 15.0%; 1.39 ± 0.42, 1.36 ± 0.31, and 1.38 ± 0.30 logMPN/m 2 , respectively). The Salmonella prevalence and load increased substantially from flaming to splitting stage. Six serovars were represented among 122 Salmonella isolates; S . Derby and S . Typhimurium were predominant and were subtyped using PFGE and CRISPR typing approaches. Fourteen PFGE clusters were identified, with discrimination indices (DI) of 0.929 and 0.976 for S . Derby and S . Typhimurium, respectively. Clusters A1, A2, B, C1, C3, C4, D1, F, I, J, L1, M2, and N2 indicated the isolates from same sampling visit were distributed in same cluster. Cluster D1 and K showed that the strains isolated from splitter and carcass swab-samples were highly resemble. Salmonella serovars with the same CRISPR type were mostly isolated after splitting (represented by Dercr 1, Dercr 2, Dercr 3, Tycr 1, Tycr 2, Tycr 3, Tycr 4, and Tycr 6). Our findings revealed that introduced Salmonella was the major source of swine carcass contamination; three slaughtering steps (polishing, rectal drilling, and evisceration) between flaming and splitting were important risk points for Salmonella release, post-splitting slaughtering processes were major contamination risk points, and the splitter was a contamination factor. Our data suggest routes for controlling Salmonella contamination in a swine slaughterhouse. [ABSTRACT FROM AUTHOR]

In order to ascertain the contamination status of Salmonella from carcass, equipment, environment and the intestinal contents in a pig slaughterhouse in Huaian, China, we investigated the prevalence and characteristics of Salmonella isolates in one slaughterhouse. A total of 636 samples were collected; Salmonella was laboratory-confirmed from 154/441 (34.9%) carcass swab-samples, 13/57 (22.8%) pieces of equipment, 30/86 (34.9%) environmental samples and the intestinal contents of 19/52 (36.5%) animals. Salmonella was found to be at its highest and lowest frequency during splitting (55.9%) and flaming (17.2%) processes, respectively. All Salmonella isolates were characterized by serotyping, multilocus sequence typing (MLST) and 69 S . Derby isolates were analyzed using pulsed-field gel electrophoresis (PFGE). Four serovars ( S . Derby, S . Rissen, S . Typhimurium, and S . London) were shared from the four sources and predominant serovars were S . Derby and S . Rissen. MLST results indicated that ten different STs were distinguished, of which ST40 was identified as the most prominent ST. Moreover, ST40, ST469, ST34 and ST155 comprised Salmonella isolates obtained from carcass, equipment, the slaughterhouse environment and intestinal contents. PFGE results showed that 33 pulsotypes (PF1-PF33) were identified. PF21, PF25 and PF29 suggested that many isolates from carcass-swab samples at different slaughterhouse process points were of the same pulsotype which also partly comprised isolates from equipment, the environment and intestinal contents. The present study provides an insight into Salmonella distribution in a pig slaughterhouse and revealed that cross-contamination occurs frequently at different sites, which provides data support for proposing some interventions to control Salmonella . [ABSTRACT FROM AUTHOR]

To obtain a green carrier for intestinal targeted delivery, an emulsion gel was designed by the self-assembly between gelatin and Pickering emulsion based on gallic acid modified-chitosan nanoparticles (GCS NPs). The emulsion gels loaded with garlic essential oil (Geo) and curcumin (Cur) were abbreviated as GOEG and GCEG, respectively. Meanwhile, the sodium alginate bead loaded with Geo (GOEGS 3) and the bead loaded with Cur (GCEGS) were prepared as controls. Results demonstrated that the emulsion gels significantly improved the bioaccessibility of Geo and Cur, showing great intestinal targeting delivery properties comparable to that of sodium alginate beads. Moreover, Caco-2 cell experiments indicated that GOEG and GCEG displayed good biocompatibility and enhanced cellular uptake of Geo and Cur. The emulsion gels also exhibited excellent anti-inflammatory properties in the lipopolysaccharide-induced cell model, exhibiting great potential for clinical application. This work provides some references for the preparation of multifunctional emulsion gels with excellent delivery performance by a green method. [Display omitted] • The modified chitosan nanoparticles with good emulsification and biocompatibility. • Emulsion gel is formed by self-assembly of modified chitosan and gelatin. • Emulsion gel combines delivery and anti-inflammatory properties. • Emulsion gel can improve the cellular uptake of lipid-soluble actives. [ABSTRACT FROM AUTHOR]

Co-based catalysts are promising alternatives to replace expensive Pt- and toxic Cr-based catalysts for propane dehydrogenation (PDH), while the catalytic stability and propylene selectivity have been subjected to the diversity of Co speciations. Given the situation, uniformly stable hydroxylated Co2+ silicate sites (depicted as {OH–Si–(OH)–Co–O–Si-(OH) 3 }) are successfully embedded into the silicalite-1 zeolite framework located in the straight and intersection channels (Co@S-1) with the assistance of Co precursors and geminal silanols via a facile hydrothermal synthesis, as revealed by detail characterizations. Under comparable conditions, a superior catalytic PDH performance with attractive propylene formation rate of 14.6 mmol·g cat −1·h−1, propylene selectivity higher than 93% and very low deactivation rate of 0.0206 h−1 after 7 h is achieved over the Co@S-1(EDA) catalyst. Furthermore, the catalytic performance can be restored to the same as that of the fresh catalyst after 3 successive regenerations. In situ FTIR spectra analysis further reveals the dynamic changes in the characteristic absorption bands associated with the hydroxylated Co2+ silicate sites and the intermediate product (2-propyl) during the PDH reaction and a reaction mechanism is proposed accordingly. This work provides a new insight for designing high-efficiency nonprecious metal PDH catalysts. [Display omitted] • Coordination environments of Co precursor complexes were precisely modulated. • Hydroxylated Co2+ silicate sites were fabricated with the assistance of Co precursors and geminal silanols. • Co@S-1(EDA) catalyst exhibited superior catalytic performance in PDH reaction. • A possible reaction mechanism was proposed from in situ FTIR spectra. [ABSTRACT FROM AUTHOR]

• DOX/IpYR achieved high penetration and long-term retention simultaneously. • DOX/IpYR regulated the expression of immune factors and PD-L1. • DOX/IpYR suppressed tumour growth and metastases. Conventional intratumoural drug delivery systems often struggle to achieve both high permeability and long-term retention. Smaller nanoparticles (NPs) readily diffuse into deep tumour regions, but their rapid clearance results in lower accumulation at tumour sites. Furthermore, although immunostimulatory molecules have been introduced for the immunotherapy of tumours, it is crucial to develop drug nanovehicles with immunomodulatory functions. Here, a novel self-assembled amphiphilic peptide, IpYR, self-assembled into spherical NPs after drug loading, which were transformed into nanofibres (NFs) with a high aspect ratio under the induction of alkaline phosphatase (ALP). This drug-loading system effectively prolonged the residence time of the chemotherapeutic drug in tumour tissues and displayed enhanced aggregation at tumour sites in vivo. Furthermore, the transformable peptide NPs not only inhibited tumour growth but also suppressed tumour metastasis. Importantly, the peptide nanovehicles inhibited the proliferation of Treg cells, downregulated the expression of immunosuppressive factors and PD-L1, and simultaneously stimulated the expression of immunogenic factors, effectively alleviating the immunosuppressive microenvironment. In conclusion, this transformable peptide-based nanodelivery system is a concise and promising nanoplatform for maintaining potent drug enrichment and inhibiting immunosuppression in the tumour microenvironment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Coordination environments of Ni precursor complexes were precisely controlled. • Bifunctional Ni@S-1 catalysts developed from the evolution of hydroxylated Ni phyllosilicate. • Superb CO 2 -CH 4 reforming behavior benefited from the synergy of tailored metal–acid sites. • A benign balance between formation and elimination of "process carbon" species was established. Ni-based catalysts using siliceous materials as the supports have suffered from two challenging issues of sintering and carbon deposition for dry reforming of methane (DRM), resulted from a weak metal-support interaction. Given these, a novel metal–acid bifunctional Ni@S-1 zeolite catalyst is tailored from the evolution of hydroxylated nickel phyllosilicates that are formed by subtly controlling the coordination environments of Ni precursor complexes in the silicalite-1 (S-1) zeolite. The developed Ni 0.44 @S-1 catalyst renders almost equivalent CH 4 and CO 2 conversions (85.1 % and 88.7 %), high H 2 /CO molar ratio (about 1) and superb long-term stability during 100 h with no activity loss at 750 °C with a WHSV of 100 L·g cat −1·h−1, outperforming other control catalysts under investigation. Such superior catalytic behavior benefits from the synergy between highly uniform Ni nanoparticles (3–5 nm) confined in the micropores of zeolite and substantially formed Lewis acid sites due to coordinatively unsaturated Ni2+ sites located at the reduced 2:1 nickel phyllosilicate, as revealed by detailed characterizations. Meanwhile, it further discloses that a benign balance between formation and elimination of "process carbon" species is responsible for improving the carbon resistance of catalyst during the DRM reaction. The present design broadens a new insight for the development of new Ni-based catalysts with simultaneous coking- and sintering-resistant for the DRM application. [ABSTRACT FROM AUTHOR]

It is an important task to real-time monitor biogenic amines (BAs) released from perishable seafood for predicting their freshness. To this endeavor, herein we developed a simple and effective strategy for visual determination of BAs by dual-emissive metal-organic framework (MOF) probes and color-transition hydrogels. Through situ encapsulating Ru(bpy) 3 2+ into UiO-OH, the functionalized Ru@UiO-OH was solvothermally prepared. At a single excitation wavelength, the fluorescence intensity of Ru@UiO-OH at 537 and 600 nm showed different changes in the case of trimethylamine (TMA), leading to a ratiometric platform with apparent color variation from orange red to bright yellow. The achieved turn-on yellow emission resulted from the inhibition of LMCT and ESIPT process caused by MOF skeleton damage and deprotonation. Intelligently, Ru@UiO-OH was loaded into hydrogels that acted as "sniffing" trademarks to detect volatile TMA vapor, which was further integrated with a smartphone-based readout to quantify. Meanwhile, the practical applicability of fluorescent sensory hydrogels was confirmed via depicting the spoilage degree of shrimp and fish at 4 and 20 ℃, the results were good consistent with standard method for detection of total volatile basic nitrogen (TVB-N). The current creation holds great significance for precise guidance of sensing seafood freshness with straightforward manner. [Display omitted] • Dual-emitting Ru@UiO-OH has been solvothermally prepared by situ encapsulation. • The red-emission acted as a reference, overcoming the interference of environment. • Hydrogel-based "sniffing" sensing platform with color transition was constructed. • The hydrogel label successfully described the spoilage degree of shrimp and fish. [ABSTRACT FROM AUTHOR]

Polymerase chain reaction (PCR) is one of the most common methods for rapid monitoring of foodborne pathogens; however, it requires purified nucleic acid as a template. Conventional nucleic acid purification is a time-consuming and laborious process. To overcome this, we developed polydopamine nanospheres (PDA NPs)-assisted direct PCR for detecting Escherichia coli O157:H7 (E. coli O157:H7). PDA NPs significantly enhanced PCR efficiency because of their strong interaction with PCR reagents, including polymerase and primers, thereby enabling regulation of the PCR performance. The optimal concentration and diameter for PDA NPs were 0.10 μg/μL and 504 nm, respectively. The PDA NPs-assisted direct PCR exhibited high sensitivity in E.coli O157:H7 detection. The detection limit of PDA NPs-assisted direct PCR was 6.7 × 104 CFU/mL, which was 10-fold lower than that of direct PCR (6.7 × 105 CFU/mL). Moreover, the sensor demonstrated excellent selectivity against E. coli O157:H7, with a negative reaction to eight other common pathogens. Most importantly, the PDA NPs-assisted direct PCR detected the order of 104−5 CFU/mL E.coli O157:H7 in milk, beef, and watermelon samples. No cultural enrichment was required, with the whole process taking <3 h. Therefore, PDA NPs-assisted direct PCR has tremendous potential in the rapid and sensitive detection of pathogens. [Display omitted] • Polydopamine nanospheres-assisted direct PCR was developed. • Direct PCR shortens the detection time due to the DNA extraction step being omitted. • Polydopamine nanospheres can improve PCR efficiency by interaction with PCR reagents. • The sensor was used in real samples for E. coli O157: H7 detection with good results. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel electrochemical sensor for classifying DNA structure was developed. • Six different aminoglycoside molecules acted as receptors. • The sensor could classify different DNA structures through molecule-DNA recognition. • Principal component analysis was employed to analyze data. Herein, we reported the differential binding ability of aminoglycosides to DNA structures using electrochemical method through principal component analysis (PCA) to classify different DNA secondary structures and understand the link between secondary structure and DNA conformation. In these analyses, the DNA with different secondary structure motifs: bulge, internal loop, hairpin loop and stem loop were designed. The aminoglycosides as receptors were modified on the surface of electrode. In the presence of DNA, the DNA will be absorbed on the surface of electrode via the recognition of DNA and aminoglycosides, resulting in the electrochemical signal observed in [Fe(CN) 6 ]3-/4-. Furthermore, the DNA structures labeled with 2-aminopurine (2-AP) at the structural motif of interest were also employed to study the binding affinity between aminoglycosides and different DNA motifs. The PCA suggested that this method may achieve nucleotide-specific classification of two independent secondary structure motifs, and the structure and sequence of DNA and the size and structure of small molecule could affect the binding ability of the aminoglycosides and DNA. This approach presents a new approach to classify DNA structure and offers ideas for designing targeted drugs small molecule compounds for wound dressing and drug delivery. [ABSTRACT FROM AUTHOR]

Antireflective coatings with adjustable transmittance and high laser-induced damage threshold (LIDT) have been prepared by the deposition of magnesium fluoride (MgF 2 ) nanoparticles on fused silica substrates. The peak transmittance of the coatings is 99.98%, mainly due to the low refractive index caused by the introduction of porosity between MgF 2 nanoparticles. With varying the coating thickness, the optimized antireflective performance of the coatings at any wavelength between 300 and 1100 nm can be achieved. The effect of the particle size on the antireflective properties of the coatings has been also investigated. The coatings prepared from small particles exhibit higher transmittance at short wavelengths than do the coatings prepared from large particles. The LIDTs of the coatings at 351 nm, 527 nm and 1053 nm are 25 J/cm 2 , 34 J/cm 2 and 63 J/cm 2 , respectively. The high LIDT of the coatings can be mainly attributed to the large band gap of MgF 2 . The antireflective coatings may be potentially applied in the high-powered lasers. [ABSTRACT FROM AUTHOR]

• The rideability of mechanical elastic wheel is analyzed at first time. • Mechanical elastic wheel can be used in damaged conditions. • The rideability can be analyzed by the rigid-flexible coupling ring model with travelling mode superposition method. • The axisymmetric damage of the wheel is better than neighboring chain damage. • The simulation time cost of ring model is less than that of finite element model. In this paper, it is first time to study rideability of mechanical elastic wheel (MEW) in damaged conditions and discuss whether the wheel with local damage conditions will be failure during running. This paper is first time to propose a rideability evaluation method of damaged MEW. For getting the parameters about displacement acceleration of rings and tensile force of chains required from the evaluation method, a rigid-flexible coupling model 'ring model' of running MEW was established, the solution method of the model was also given by travelling mode superposition method. The ring model was compared with the experiment and finite element method to verify its accuracy. With using the verified ring model, the rideability simulation was analyzed under eight kinds of speeds and six kinds of damaged working conditions. The results show that: MEW with one or two damaged chains still has the receptible rideability and is not failure, and it provides security for the safe driving of vehicles in emergency situations; when damaging three chains, the wheel can be used to run at low speeds, the rideability of wheel at high speeds will deteriorate and the wheel will be failure; the rideability of MEW with axisymmetric chain damage is better than that with neighboring chain damage; it also finds that the simulation calculation time of ring model is much lower than that of finite element method, the time cost will be saved. [ABSTRACT FROM AUTHOR]

• A novel and sensitive fluorescent sensor was developed for tetracycline detection. • The prepared tungsten oxide quantum dots exhibited low toxicity and superior optical property. • The sensing mechanism was studied by theoretical calculation and optical spectra. • This prominent technique could be applied in milk and milk powder samples. Tetracyclines (TCs) residues in animal products have attracted extensive concern due to their potential toxic to human health. Accordingly, it is urgent to develop an efficient method to determine TCs for providing consumers with risk pre-warning. Herein, a novel tungsten oxide quantum dots (W x O y QDs) fluorescence probe for tetracycline (TET) detection was constructed through ethanol-thermal method, which exhibited intense blue fluorescence under 365 nm UV light. Interestingly, blue-emitting W x O y QDs could be quenched obviously after the addition of TET, which may be attributed to the synergism of inner filter effect (IFE), fluorescence resonance energy transfer (FRET) and photo-induced electron transfer (PET). Thereby, the fluorescence method was established for TET detection based on W x O y QDs. Additionally, the presented method was demonstrated by monitoring TET in milk and milk powder with satisfactory recoveries. More importantly, this work offered good demonstration for the detection of food hazard factors. [ABSTRACT FROM AUTHOR]

Herein, a cost-effective, simple and sensitive electrochemical sensing platform was established based on aptamer - target recognition and target-triggering signal amplification strategy for protein detection. Due to the high affinity between the aptamer and target, the assistant DNA1 (a1) could release from a1-aptamer duplex and trigger the following DNA circuits. The strand displacement and branch migration reaction brought assistant DNA3 (a3) released. Eventually, a large number of duplex structures of a3−Hairpin DNA3 were formed on the surface of electrode. Consequently, the capture DNA on the surface of platinum nanoparticles could hybridize with the unfolded DNA fragment of Hairpin DNA3 on the sensor surface, resulting in the electrochemical signal readout of H 2 O 2 reduction. Using thrombin as a model target, under the optimal conditions, this method exhibited a linear detection range from 0.5 pM to 300 nM with a detection limit of 0.17 pM. The proposed detection strategy was enzyme-free and exhibited good selectivity and sensitivity for a variety of protein targets detection by using corresponding DNA-based affinity probes, which makes it possible to apply the sensor for sensitivity detection of analytes in bioassays. A novel electrochemical sensing platform based on target-triggering cascade enzyme-free signal amplification strategy was developed for sensitive protein detection. [Display omitted] • Electrochemical detection of thrombin using target-triggering cascade enzyme-free signal amplification strategy was proposed. • The method was PCR-free, enzyme-free, low cost, and without the need for any additional separation steps. • The sensor for thrombin showed good performance. [ABSTRACT FROM AUTHOR]

A new type of "turn-on" fluorescence probe coumarin-based DTC was developed for specifically detecting hypochlorite ion (ClO−) with high sensitivity. DTC can display a significant enhancement of fluorescence and emit blue fluorescence at 452 nm after reaction with ClO−. Moreover, probe DTC can detect ClO− without interference from other reactive oxygen species (ROS), and has a low detection limit for ClO− of 96 nM. Meanwhile, DTC can also detect ClO− in the physiological environment, and DTC can be further used as a test paper-strip for portable and rapid detection of ClO−. [Display omitted] • A novel "turn-on" fluorescence probe DTC was developed for detecting hypochlorite ion. • DTC can detect ClO− with a low detection limit as 96 nM. • DTC has high selectivity towards ClO− and can be applied in the physiological environment. • DTC is successfully integrated on a paper-strip to detect ClO−. [ABSTRACT FROM AUTHOR]