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Monogenea, a prevalent parasite in aquaculture, poses significant threats to the industry, leading to substantial losses. Current preventive measures have proven insufficient, necessitating the development of novel and effective anti-parasitic drugs. In this investigation, we obtained the full-length myosin cDNA sequence by analyzing three-generation transcriptome data, revealing a 5817-base sequence encoding 1938 amino acids. Subsequently, we modeled and analyzed the characteristics of the secondary and tertiary of myosin, pinpointing the crucial functional region within the motor domain (amino acids 1–768). The prokaryotic expression of this domain yielded a protein of 87.44 kDa, confirmed as myosin by Western Blotting. Molecular docking identified ASN439 as the key amino acid residue involved in arctigenin and myosin binding, a result corroborated by site-directed mutagenesis, affirming the active cavity of this interaction. Chalcone and shikonin were chosen from a virtual sieve of molecular library of natural drugs based on the active cavity. Chalcone and shikonin exhibited EC 50 values of 1.085 mg/L and 0.371 mg/L, respectively, with corresponding IC 50 values for myosin of 0.44 mM and 0.14 mM. Given its superior activity and structure, shikonin was selected for further optimization of drug molecule design, culminating in the discovery of 1,4-naphthoquinone as a potent antiparasitic agent. This compound demonstrated an EC 50 of 0.047 mg/L, LC 50 of 0.23 mg/L, and a TI index of 4.893. These findings collectively highlight the potential of shikonin and 1,4-naphthoquinone as alternative compounds to control Gyrodactylus infections. Further optimization of medicinal chemistry holds promise for the development of more potent 1,4-naphthoquinone analogues, offering prospects for future anthelmintic control through combinatorial or replacement strategies. Through molecular docking and site-directed mutagenesis, the binding activity of arctigenin with myosin was verified. Subsequently, shikonin, a potent antiparasitic agent and myosin inhibitor, has been identified through virtual screening techniques. Using shikonin as a lead compound, a series of derivatives were designed, ultimately leading to the discovery of 1,4-naphthoquinone, a highly effective anti-parasitic drug. [Display omitted] • Arctigenin effectively eradicates parasites by acting as a potent inhibitor of myosin. • Shikonin, an effective myosin inhibitor, has been identified by drug virtual screening. • Shikonin stands out as a highly potent small molecule with antiparasitic properties. • 1,4-naphthoquinone serves as a highly potent antiparasitic agent. [ABSTRACT FROM AUTHOR]

A multicomponent functionalized nano-material (Au@CP5@MoS 2) is prepared by control assembly of Au nanoparticles on the surface of CP5@MoS 2 for sensing and catalysis reduction of toxic explosives p -dinitrobenzene (p -DNB). Firstly, the Au nanoparticles are obtained by a green redox reaction between HAuCl 4 and hydroxylatopillar[5]arene (HP5) in the presence of a small amount of hydroxide ion without any harsh reduced agent. The CP5@MoS 2 is prepared by a rapidly supramolecule mediated hydrothermal route in the presence of aqueous solution of cationic pillar[5]arene (CP5). Therefore, we construct an electrochemical sensing platform for the high sensitive and selective determination of p -DNB based on the excellent supramolecular recognition of CP5/HP5 and the high catalytic activity of Au nanoparticles. Moreover, the p -DNB can be reduced into 1,4-diaminobenzene by NaBH 4 in the presence of the prepared Au@CP5@MoS 2 , which can reduce the explosion dangerousness of p -DNB to some extent. This strategy might present a prospective value in sensing and reducing toxic explosives. Image 1 • A multicomponent functionalized material (Au@CP5@MoS 2) was prepared. • An electrochemical sensing platform for determination of p -DNB was developed. • The p -DNB can be reduced into 1,4-diaminobenzene by NaBH 4 in the presence of the Au@CP5@MoS 2. • The host-guest interaction between host CP5 and guest p -DNB was studied by 1H NMR. [ABSTRACT FROM AUTHOR]

Both increasing environmental issues and the lack of fossil resources have increased the importance of wood-based natural fiber composites. Therefore, high performance, sustainable, and environmentally-friendly bio-based wood adhesives are highly desirable. We developed a new biomass adhesive based on aminated cellulose (AC) and oxidized sucrose (OS), and reinforced it with an activated wood interface to improve its bonding performance. To this end, the natural wood interface (NWI) was customized with an epoxy group to produce the epoxy-functionalized wood interface (EFWI), one end of which is tethered to the wood surface. The epoxy group at the other end reacts with the amino group of AC, resulting in hydrophobicity and forming new covalent bonds in the adhesive layer, such as -Si-O-Si-, -Si-O-C-, -C-N-C-, and -O-C-C- bonds. Characterization of the adhesive interface is realized by FTIR, 13C NMR, XPS, XRD, and SEM. Dry and wet shear strengths are also investigated by tensile shear strength measurements in China National Standards (GB/T 9846-2015). Results show that OS-AC adhesives have better dry and wet shear strengths at EFWI in comparison with those on NWI, reaching 2.52 and 1.48 MPa, respectively. Thus, the construction of a functionalized wood adhesive interface dramatically enhances the bonding strength and water resistance of biomass adhesives. This study provides new insights for developing renewable, low cost, and green bio-based wood adhesives by chemical modification of the wood interface. Schematic diagram for the design and construction of strong wood bonding via chemical bond between epoxy-functionalized wood surface and cross-linked OS-AC bio-based adhesive. [Display omitted] • Biomass adhesive based on cellulose-sucrose cross-linked network was developed. • Bonding performance was reinforced with functionalized wood interface. • OS-AC adhesive has better shear strengths at EFWI in comparison with that on NWI. • Functionalized wood interface enhances the water resistance of the biomass adhesive. [ABSTRACT FROM AUTHOR]

Porous nanosheet-structured materials have received great attention because of their promising applications in energy field. Construction of porous metal oxides nanosheets on three-dimensional (3D) electro-conductive substrates is an effective way to further enhance electrochemical performance of energy storage devices. Herein, porous transition metal oxides (i.e. ZnO, Co 3 O 4 ) nanosheets derived from MOFs coated 3D substrates (i.e. 3D nickel foam, carbon fiber) are successfully synthesized by a facile liquid-phase deposition method with subsequent calcination. The growth mechanism of MOFs with nanosheet morphology coated 3D substrates is investigated. As a proof of concept application, the Co 3 O 4 /3DNF hybrid, possessing the advantages of porous nanosheet-structured and 3D electro-conductive substrates, is used as a binder-free anode material for lithium-ion battery, which exhibits high-rate capability and long-term cyclic stability. High discharge capacities of 1135, 1268, 1226, 1130, 923, 751, and 543 mA h g −1 are obtained at the current densities of 0.2, 0.5, 1, 2, 5, 10, and 20 A g −1 , respectively. Even measured at 25 A g −1 , it still retains a desired discharge capacity of 364 mA h g −1 . Besides, the long-term cyclic stability up to 2000 cycles can be obtained at 5 A g −1 and 20 A g −1 . [ABSTRACT FROM AUTHOR]

• Biphasic Fe 7 S 8 @MnS heterostructure embedded in sulfur-doped carbon matrix was synthesized. • The composites exhibit enhanced lithium storage performance with high rate capability and long cycling stability. • These results can be attributed to the multiphasic components with heterostructures and porous conductive carbon frameworks. Transition metal chalcogenides have been regarded as promising anode candidates for lithium-ion batteries, featured by their high capacity and abundant material choice. However, their practical implementation was hindered by the poor reaction kinetics and rapid capacity fading due to their low electronic conductivity and severe volume variation upon the (de-)lithiation processes. Here, we have successfully fabricated the biphasic Fe 7 S 8 @MnS heterostructure embedded in sulfur-doped carbon matrix by direct sulfidation of Fe/Mn bimetal-organic frameworks. The biphasic heterostructure and the porous carbon frameworks can create abundant phase boundaries and multiple conductive channels for change transfer, thus improving the electronic conductivity and contact area with electrolyte, leading to facilitated charge transfer capability. As a result, the Fe 7 S 8 @MnS/C composites exhibit superior lithium storage performance with a specific capacity of 917 mA h g−1 at 0.1 A g−1 and maintain at 581 mA h g−1 after 500 cycles at 1 A g−1. This work provides an efficient strategy for constructing multiphase nanomaterials towards high performance anodes for Li-ion batteries. [ABSTRACT FROM AUTHOR]

Noxious pathogens always lead to high rates of mortality, which results in severe economic losses in aquaculture. Currently, gyrodactylosis treatments mainly rely on unapproved chemicals, which are not always satisfactory. According to the previous study, arctigenin is an efficient natural product for controlling gyrodactylosis. For the sake of seeking high-efficiency compounds, a new arctigenin derivative (CCA) was synthesized. Next, we evaluated the anthelmintic activity of CCA in vitro and in vivo , and studied the mechanism of action. The number of Gyrodactylus kobayashii significantly reduced as compared with the control group, the EC 50 value at 24 and 48-h after CCA treatment was 0.616 and 0.451 mg/L, respectively, with EC 100 at CCA concentration of 3 mg/L after 1 h bath treatment. In vitro results showed that CCA can rapidly reduce the amount of G. kobayashii and inhibit its mobility that could normally lead to death. The concentration and duration of CCA were positively correlated with the mortality of G. kobayashii. In addition, CCA displayed 100% efficacy against G. kobayashii at 4.0 mg/L after only 20 min exposure. Acute toxicity assay demonstrated that the LC 50 of CCA against goldfish was 5.012 mg/L, which was 8.13 times higher than that of the EC 50. Furthermore, the results of confocal microscope study revealed that CCA leaded to the epidermal structure and dissolved muscles of worms. Moreover, the ATP level of worms were decreased sharply after both in vitro and in vivo exposures with CCA. The anthelminthic mechanism of CCA against gyrodactylids was related to epidermal structure damages and energy insufficient. From the previous study, the EC 50 of CCA against G. kobayashii (0.616 mg/L) was much lower than the EC 50 (1.85 mg/L) of arctigenin (Tu et al., 2018). In summary, CCA is more effective than arctigenin and has great potential in control of Gyrodactylus infections. • A novel arctigenin derivative, chloro (3-chloropropoxy) methanone-arctigenin (CCA), was designed and synthesised. • CCA displayed a better anti- Gyrodactylus kobayashii activity than the lead compound in in vitro and in vivo. • The mechanism of CCA against gyrodactylids was related to epidermal structure damages and inhibition of ATP production. [ABSTRACT FROM AUTHOR]

Understanding the interaction between the insect olfactory system and the environment is crucial for fully explaining the molecular mechanisms underlying insect behavior, and providing new strategies for integrated pest management. Although there is good evidence that olfactory proteins play a vital role in mediating insect behaviors, the olfactory mechanism of insects remains poorly understood. We identified a total of 71 chemosensory genes; 25 odorant-binding proteins (OBPs), 27 odorant receptors (ORs), 8 ionotropic receptors (IRs), 8 chemosensory proteins (CSPs) and 3 sensory neuron membrane proteins (SNMPs), in the antennae of male and female fall armyworms, Spodoptera frugiperda , an invasive global pest that causes significant economic damage worldwide. We used differential gene expression (DGE) and fragments per kilobase per million fragments (FPKM) values to compare the transcript levels of candidate chemosensory genes, and qRT-PCR to compare the expression levels of the OR gene, in male and female antennae. The expression of candidate OR genes in male and female antennae was consistent with the DGE data, and the expression of the SfruCL4419.Contig1-All and SfruUnigene1070-All genes was sex-biased. These results not only provide new information on the olfactory mechanism of S. frugiperda , and insects in general, but also suggest new gene targets for pest control. Unlabelled Image • The total of seventy-one Spodoptera frugiperda chemosensory genes were identified from male and female antennal tissue. • The first analysis of expression levels of S. frugiperda chemosensory genes in male and female antenna. • The expression of the Sfru CL4419.Contig1-All and Sfru Unigene1070-All genes was sex-biased. [ABSTRACT FROM AUTHOR]

Ultrasensitive, high selective and rapid monitoring of explosives has increasingly become a crucial and urgent challenge in order to protect environment and prevent terrorist threats, which should be addressed timely. In this study, a highly selective and sensitive electrochemical sensing platform based on two dimensional (2D) heterogeneous functionalized material for determination dangerous and explosive sodium picrate (SP) and analogue picric acid (PA) is successfully established. To begin with, the dihydroxylatopillar [6]arene (2HP6) modified Au nanoparticles (2HP6@Au) can be easily obtained by 2HP6 reduced and stabilized Au nanoparticles at room temperature. Then, assembly of 2HP6@Au on the surface of cationic pillar [6]arene (CP6) functionalized covalent organic framework (COF) can obtain 2D heterogeneous composite (2HP6@Au@CP6@COF) for rapid and sensitive detection of SP. The electrode, best operated at a working potential of −0.4 to −1.1 V (vs. Hg/Hg 2 Cl 2), works in the concentration range of 0.005–120 μM SP and has a 0.0017 μM detection limit. The Au nanoparticles play an electrocatalytic role in sensing SP, the 2HP6 and CP6 serve as a prominent material for gathering and recognition SP onto the surface of electrode, respectively. The SP can thread into the cavity of pillar [6]arene and form a 1:1 [2]pseudorotaxanetype complex. The SP can be highly captured by CP6 via the excellent supramolecular host-guest interactions (including π interaction, hydrophobic interactions and electrostatic interactions). Consequently, this work might present a green strategy for preparation 2D heterogeneous functionalized hybrid material in catalysis, sensing and other fields. Schematic illustration of the 2HP6@Au@CP6@COF hybrid nanomaterial application in sensing towards sodium picrate. Image 1 [ABSTRACT FROM AUTHOR]

Direct fixation of N 2 at room temperature by photocatalysis is the most intriguing process toward sustainable production of ammonia, where chemisorption of inert N 2 and delivery of photogenerated electrons to N N bond are recognized bottlenecks. Here, we develop a catalyst of amorphous SmOCl nanosheets (A-SmOCl) with remarkable activity for photocatalytic reduction of N 2. Impressively, the ammonia production rate of A-SmOCl reached 426 μmol·g cat. −1·h−1 under light irradiation in water without any sacrificial agents. Moreover, A-SmOCl exhibited an apparent quantum efficiency of 0.32% at 420 nm. Further mechanistic studies revealed that the existence of abundant oxygen vacancies in A-SmOCl significantly improved the adsorption and activation of N 2. Meanwhile, the enhanced Sm–O covalency promoted the delivery of photogenerated electrons to chemisorbed N 2 , contributing to the superior catalytic activity of A-SmOCl. A-SmOCl exhibited the ammonia production rate of 426 μmol·g cat. −1·h−1 attributed to the existence of abundant oxygen vacancies and enhanced Sm–O covalency. Image 1 • We developed a catalyst of amorphous SmOCl nanosheets (A-SmOCl) with abundant oxygen vacancies. • The NH 3 production rate of A-SmOCl reached 426 μmol·g cat. −1·h−1 under light irradiation without any sacrificial agents. • A-SmOCl exhibited an apparent quantum efficiency of 0.32% at 420 nm. • The existence of abundant oxygen vacancies in A-SmOCl significantly improved the adsorption and activation of N 2. • The enhanced Sm–O covalency promoted the delivery of photogenerated electrons to chemisorbed N 2. [ABSTRACT FROM AUTHOR]

We develop a novel and fast colorimetric sensing platform for spermine (Sp) by using macrocyclic host hydroxyl pillar[5]arene (P5) molecule reduced and stabilized Au nanoparticles via the supramolecular host-guest recognition interaction between P5 and Sp. The P5-modified Au nanoparticles (P5-Au) are easily obtained by redox reaction between hydroxyl groups in P5 and Au3+ in HAuCl 4 , where hydroxyl groups are oxidized to carboxyl groups and Au3+ is reduced to Au0+ under alkali catalysis at room temperature without NaBH 4 or other reducing agent. A uniform diameter of about 5.0 nm and wine red color P5-Au nanoparticles can be synthesized by this green and rapid method. The mechanism of redox reaction between P5 and HAuCl 4 is studied by the XPS and 13C NMR, and the P5-Au is characterized by the TEM, XRD and XPS. A novel colorimetric sensing for detection of spermine based on supramolecular pillar[5]arene reduced and stabilized gold nanoparticles. Unlabelled Image • The hydroxyl pillar[5]arene (P5) reduced and stabilized Au nanoparticles (P5-Au) were prepared by redox reaction. • Spermine or its analogues can induce the aggregation of P5-Au nanoparticles. • The hydroxyl groups in P5 are oxidized to carboxyl groups and the Au3+ in HAuCl 4 is reduced to Au0. [ABSTRACT FROM AUTHOR]

Passive smoking is considered a major public health issue in China. Prospective evidence regarding the link between secondhand smoke (SHS) and ischemic stroke in China is scarce. The China Kadoorie Biobank (CKB) study in Liuzhou City recruited 50,174 participants during 2004–2008. Of these 30,456 never-smokers were included in our study. The median follow-up period was 10.7 years. The incidence of ischemic stroke was obtained through the China Disease Surveillance Points (DSP) system and the Health Insurance (HI) database. Cox proportional risk models were used to evaluate the association between SHS exposure and ischemic stroke. During 320,678 person-years of follow-up, there were 2059 patients with ischemic stroke observed and the incidence of ischemic stroke was 6.42 per thousand person-years. Participants exposed to SHS daily faced a 21 % higher risk of ischemic stroke (HR = 1.21, 95 % CI : 1.09–1.34) compared to those exposed to SHS less than once a week. Subgroup analyses revealed that daily SHS exposure was linked to heightened risk of ischemic stroke among women, non-employed, and non-weekly tea drinkers. Daily SHS exposure was associated with higher risks of ischemic stroke. Proactive tobacco control strategies are necessary to decrease the risk of ischemic stroke in never smokers. [ABSTRACT FROM AUTHOR]

Abstract: The corrosion behavior of Mg–7Gd–3Y–0.4Zr (GW73K) was investigated in as-cast (F), solution-treated (T4) and peak-aged (T6) conditions using immersion tests and electrochemical measurements in NaCl solution (5wt.%). Microstructure analyses were carried out on GW73K after different heat treatments by optical microscope (OM), field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM) and X-ray diffraction. It is found that GW73K alloy exhibits higher corrosion resistance in T4 than in F and T6 conditions due to the fully dissolution of cathodic coarse (Gd+Y) rich eutectic compound. The corrosion products of GW73K have different morphologies for F, T4 and T6 conditions. The product for F is less uniform and compact than T4 and T6, and it has been founded that GW73K-T6 had two different morphologies owing to the presence of β′. The results of polarization curves also confirm that proper heat treatment is beneficial to improve the corrosion resistance of GW73K alloy by transforming the microstructures. [ABSTRACT FROM AUTHOR]

Rational design of environmentally friendly and sustainable bio-based wood adhesives is of great significance to people's health, environmental protection, high value-added utilization of crop resources and national economic development. In this work, we develop new cellulose-based wood adhesives and explore the differences in the spatial structure of branched polyamines and linear binary amines after cross-linking with dialdehyde cellulose (DAC). The bio-based wood adhesives DAC-2N (adhesives obtained from the reaction of DAC with diethylenetriamine) and DAC-3N (adhesives obtained from the reaction of DAC with tris(2-aminoethyl)amine) are prepared by the cross-linking reaction between DAC and linear amines (2 N)/branched amines (3 N). The effects of spatial cross-linking degree, mass ratio of amine to DAC and solid content of adhesives on the bonding performance are systematically studied, and the mechanical properties of wood specimens are also tested by universal mechanical tests. Results show that the best formulation of DAC adhesive is a 1:1 mass ratio of DAC to 3 N, and the optimal solid content is 40%. Compared with the pristine DAC adhesive, the dry bonding strength of the DAC-3N adhesive increased by 103% from 1.35 MPa to 2.74 MPa, and the wet bonding strength increased from 0 MPa to 1.81 MPa. DAC-3N adhesive with dense network structure has stronger glue and water-proof properties than DAC-2N adhesive, and the shear strength test of the three plywood shows the failure mode of the substrate rather than the failure mode of bonding or cohesion. Therefore, this study might offer a prospective strategy for future research, especially the rational design and potential application of bio-based adhesives with branched structure. Sustainable and high-performance bio-based wood adhesive via integration of branched amine and dialdehyde cellulose. [Display omitted] • Cellulose-based environmentally friendly wood adhesive was prepared via Schiff-base reaction. • The cross-linking network formed by covalent bonds and non-covalent bonds is helpful to improve the bonding properties. • The comparison of DAC-2N and DAC-3N adhesives showed that the adhesive with branched structure had higher bond strength. • Compared with pure DAC, the DAC-3N adhesive has splendid bonding strength and excellent water resistance. [ABSTRACT FROM AUTHOR]

The rational design of electrochemical methods for chiral recognition is a focus of research in the detection fields of biomolecules and pharmaceuticals. In this work, a novel, rapid, and convenient electrochemical approach for recognition of tryptophan isomers (L-/D-Trp) was constructed based on the alternating layer-by-layer assembly of water-soluble cationic and anionic pillar[5]arene on a carboxylic graphene (C-Gra) modified glass carbon electrode. Differential pulse voltammetry (DPV) was employed to study the electrochemical recognition of tryptophan isomers. The results reveal that both the peak currents of L-Trp and D-Trp decreased with the increasing of the layer number of the assembled pillar[5]arene, whereas the peak current value's difference between the L-Trp and D-Trp increased with the increased layers, which demonstrated an efficient route for discriminating the L-Trp and D-Trp. The recognition mechanism was studied by 1 H NMR spectra and molecular docking. The host−guest interaction is different for D- and L-Trp due to the opposite steric configurations of the Trp isomers, resulting in significantly discernible electrochemical differences in both peak currents and consequently effective chiral recognition of Trp isomers. This study is the first example that shows the construction of electrochemical chiral separation platform based on pillar[5]arene. This method shows potential applications in many fields, including separation, purification, storage of chiral molecule, drug detection and analysis. [ABSTRACT FROM AUTHOR]

An interface of Ru[bpy] 3 2+@Cu-MOF(-SH)/Au was electrochemically fabricated, with its photo/electrochemical bi-functional properties being characterized and the feasibility of DNA biosensing being validated. [Display omitted] • An electrochemical fabrication method of Ru[bpy] 3 2+@Cu-MOF(-SH)/Au interface was developed. • A photo/electrochemical information characterization was carried out for the interfacial bi-functional properties. • An electrochemiluminescence (ECL) 3D imaging was established for the proposed interface. • A SECM comprehensive imaging method was established to evaluate interface fabrication quality. • The feasibility of the proposed interface to construct a photoelectric bi-function coupled DNA sensor was validated. An electrochemical fabrication method of Ru[bpy] 3 2+@Cu-MOF(-SH)/Au (MOF = metal–organic framework) was developed with a photo/electrochemical information characterization and a DNA-based biosensing validation for the proposed interface. Applying an anodic synthesis method, a modification layer of Ru[bpy] 3 2+ encapsulated with MOF was formed on the Au electrode surface to fabricate an interface with photo/electrochemical dual-signal response. Combining the scanning electrochemical microscopy (SECM) imaging technology with electrochemical and electrochemiluminescence (ECL) detection, the information about the interfacial photo/electrochemical bi-functional properties was explored from three aspects of the parameter variable, intensity variable, and morphology variable. The results show that the effect of parameter variables on the interfacial response follows an "interference effect" mechanism. Under the optimized conditions, the background and the saturation ECL intensities are 610.0 and 24.0 with a quenching efficiency of 96.1% and a detection limit of 30 fM. The saturation current is 48.8 µA with a detection limit of 330.0 nM. Both ECL and electrochemical imaging methods can corroborate each other, validating the logical correlation between the interface fabrication and the response performance in the regional interfacial distribution and laying a methodological foundation for evaluating the interface fabrication quality based on imaging morphology qualitatively. The proposed interface can construct photo/electrochemical dual-signal DNA-based biosensors. [ABSTRACT FROM AUTHOR]

Abstract: Novel channel-structured β-Ag0.33V2O5 nanorods have been successfully synthesized via a simple hydrothermal process. The channels are along the axis of β-Ag0.33V2O5 nanorods and the channels are about 30nm in width. As cathode material for lithium batteries, it exhibits higher specific discharge capacity and improved cyclic stability than other silver vanadium oxides. High initial specific discharge capacity of 288mAhg−1 can be obtained at 20mAg−1 in the voltage range of 2.0–3.6V (vs. Li/Li+). A maximum high specific discharge capacity of 332mAhg−1 can be reached at 20mAg−1 within 1.5–4.0V (vs. Li/Li+). The good electrochemical performances are ascribed to the novel channel-structure and good structural reversibility upon cycling. [Copyright &y& Elsevier]

Abstract: Silver vanadium oxide (SVO, Ag0.33V2O5) was synthesized in solid-state reactions from silver nitrite (AgNO3) and the sol–gel prepared vanadyl citrate (VO(C6H6O7)). The formation mechanism of Ag0.33V2O5 was elucidated by thermal gravimetric analysis (TG) and differential scanning calorimetry (DSC) methods. The formation of Ag0.33V2O5 went through two step decomposition and combination processes. The morphology and the crystallinity of the calcination products were largely temperature dependent. The electrochemical performance of Ag0.33V2O5 cathode material was superior to many other silver vanadium oxides, which were attributed to their nanosized particles and the good structural reversibility upon cycling. [Copyright &y& Elsevier]

Abstract: The objective of this research is to study microstructure and phase evolution of zirconia–mullite (ZM) nanocomposites which were synthesized by the direct transformation from amorphous precursor monoliths. The monolithic precursors were heat treated at 950–1250°C to obtain ZM composites. Scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), transmission electron microscopy (TEM) and high resolution TEM (HRTEM) were employed to investigate the microstructure of the composites. A unique nano- and submicron-zirconia co-reinforced mullite composite microstructure was obtained after a controlled crystallization. The nano tetragonal zirconia (t-ZrO2) grains (<50nm) were spherical and embedded in the mullite lattice. The unconfined zirconia grains showed a preferred growth direction along 〈100〉 direction of t-ZrO2, and formed submicron grains (<650nm) with bar-like shape. The precursor derived ZM composites also demonstrated enhanced mechanical properties comparing with the conventional powder processed ZM composites. [Copyright &y& Elsevier]

Abstract: Ag/β-AgVO3 hybrid nanorods have been successfully prepared by a facile one-step solid-state approach and their electrochemical performance has been evaluated as cathode materials for lithium batteries (LBs). The effects of calcinations temperatures to the morphologies of the material and the content of Ag in the hybrid have been investigated. The Ag/AgVO3 hybrid synthesized at 420 °C shows well-separated nanorods anchored with Ag nanoparticles. The existence of Ag nanoparticles has been demonstrated to improve the conductivity of the electrode. As a cathode material for lithium batteries, it exhibits high specific capacity, good rate capability and improved cycle stability. Initial specific discharge capacities of 242, 228, 203, 202, 198 mA h g−1 can be achieved at the current densities of 50, 100, 200, 400, 800 mA g−1, respectively. The superior performance is attributed to the combined effect of the electron conductivity improvement by the Ag nanoparticles and the well-separated β-AgVO3 nanorod structures. The results demonstrate the advantages of the Ag/AgVO3 hybrid for primary lithium batteries, and the possible application in rechargeable lithium batteries. [Copyright &y& Elsevier]

MicroRNAs (miRNAs) serve as significant regulators in a variety of diseases and have been emerging as a class of promising biomarkers for early cancer diagnosis. Herein, an enzyme-free surface-enhanced Raman scattering (SERS) platform was proposed for sensitive and reliable detection of target miRNA-21 using a corrective internal standard (IS)-based ratiometric SERS probe coupled with mismatched catalytic hairpin assembly (CHA) amplification. The 4-aminothiophenol (4-ATP) was used as IS molecule and modified on the surface of silver nanoparticles decorated silicon wafer. In principle, the presence of miRNA-21 could cyclically trigger the allosteric effects of mismatched CHA amplification and the 3′-R6G labeled hairpin probe 1 (H1) was opened. Then, the hairpin probe 2 (H2) hybridized with H1 to form H1–H2 complex and the released miRNA-21 was free to participate in the next cycle of CHA reaction. Meanwhile, the H1–H2 complex could hybridize with the capture DNA on the SERS chip, making the Raman tag of R6G close to the surface of SERS substrate, and the intensity of SERS signal from R6G labels increase while that from 4-ATP remain relatively unchanged. Benefiting from outstanding performances of the ratiometric SERS strategy and enzyme-free CHA amplification system, this platform exhibits sensitivity toward miRNA-21 with a limit of detection of 3.5 fM and a broad dynamic range from 10 fM to 100 nM. More importantly, this proposed method presents an excellent reliable SERS analysis with the correction of IS. The developed strategy holds a potential alternative tool for miRNA detection in biomedical research and early clinical diagnosis. • A novel ratiometric SERS biosensor for miRNA was developed based on mismatched CHA amplification. • A good linear detection range for miRNA-21 in a range from 10 fM to 100 nM with the detection limit at 3.5 fM. • The proposed strategy exhibited good stability, reproducibility, and reusability. [ABSTRACT FROM AUTHOR]