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Abstract Background Rice ECQ (eating and cooking quality) is an important determinant of rice consumption and market expansion. Therefore, improvement of ECQ is one of the primary goals in rice breeding. However, ECQ-related quantitative trait loci (QTL) have not yet been fully revealed. The present study aimed to identify a major effect QTL for rice taste, an important component of ECQ via genotyping-by-sequencing, to reveal the associated molecular mechanisms, and to predict key candidate genes. Results A population of F9 recombinant inbred lines resulting from a cross between R668 (national standard of high-quality third class) and R838 (common edible rice) was used to construct a high-density genetic map (2,295.062 cM). The map comprises 639,504 markers distributed on 12 linkage elements with an average genetic distance of 0.004 cM. We detected a major taste-related QTL, qECQ8, which explained 41.4% of phenotypic variance and had LOD values of 4.42–7.73. Using a five-generation NIL population from the backcross of “Ganxiangzhan No. 1” carrying qECQ8 with the recurrent parent R838 (without qECQ8), we narrowed qECQ8 to a 187.5 kb interval between markers M33 and M37 on Chr8. Comparative transcriptomic analysis revealed that photosynthesis, glyoxylate and dicarboxylate metabolism, carbon fixation in photosynthetic organisms, and alpha-linolenic acid metabolism were induced in developing seeds of lines containing qECQ8. Furthermore, we identified two candidate genes in the qECQ8 region, including LOC_Os08g30550 (zinc knuckle family protein), a major candidate for genetic-assisted breeding of high-quality rice. Conclusion Our findings provide important genetic resources for targeted improvement of rice taste quality and may facilitate the genetic breeding of rice ECQ.

Arbuscular mycorrhizal (AM) fungi are crucial components of the plant microbiota and can form symbioses with 72% of land plants. Researchers have long known that AM symbioses have dramatic effects on plant performance and also provide multiple ecological services in terrestrial environments. The successful establishment of AM symbioses relies on the host plant recognition of the diffusible mycorrhizal (Myc) factors, lipo-chitooligosaccharides (LCOs) and chitooligosaccharides (COs). Among them, the short-chain COs such as CO4/5 secreted by AM fungi are the major Myc factors in COs. In this review, we summarize current advances, develop the concept of mycorrhizal biceptor complex (double receptor complexes for Myc-LCOs and CO4/5 in the same plant), and provide a perspective on the future development of mycorrhizal receptors. First, we focus on the distinct perception of two Myc factors by different host plant species, highlighting the essential role of Lysin-Motif (LysM)-type mycorrhizal receptors in perceiving them. Second, we propose the underlying molecular mechanisms by which LysM-type mycorrhizal receptors in various plants recognize both the Myc-LCOs and -COs. Finally, we explore future prospects for studies on the biceptor complex (Myc-LCO and -CO receptors) in dicots to facilitate the utilization of them in cereal crops (particularly in modern cultivated rice). In conclusion, our understanding of the precise perception processes during host plant interacting with AM fungi, where LysM-type mycorrhizal receptors act as recruiters, provides the tools to design biotechnological applications addressing agricultural challenges.

This study summarized and evaluated the cost-benefit analysis methods for typical water environment pollution control measures in China. We conducted a comprehensive comparison of these measures, whose advantages and disadvantages were examined, so the application models and characteristics can be delved into. Through integrating methods and analyzing application cases, we refined a combination of measures with high efficiency and low cost in controlling China’s water environment. In our analysis of cost-benefit, we emphasized the importance of implementing scientifically designed control measures and employing rigorous methods to addressing water environment pollution. In order to achieve rapid response and efficient treatment of China’s environmental problems, we advocated for establishing a cross regional pollution control mechanism. That is, the collaborative platform and scientific suggestions for all participants in this field should be provided, through interdisciplinary integration, development of domestic models, and expansion of databases.

Metallic structures with hierarchical open pores that span several orders of magnitude are ideal candidates for various catalyst applications. However, porous metal materials prepared using alloy/dealloy methods still struggle to achieve continuous pore distribution across a broad size range. Herein, we report a printable copper (Cu)/iron (Fe) composite ink that produces a hierarchical porous Cu material with pores spanning over 4 orders of magnitude. The manufacturing process involves four steps: 3D-printing, annealing, dealloying, and reannealing. Because of the unique annealing process, the resulting hierarchical pore surface becomes coated with a layer of Cu–Fe alloy. This feature imparts remarkable catalytic ability and versatile functionality within fixed bed reactors for 4-nitrophenol (4-NP) reduction and Friedländer cyclization. Specifically, for 4-NP reduction, the porous Cu catalyst demonstrates an excellent reaction rate constant (kapp = 86.5 × 10–3 s–1) and a wide adaptability of the substrate (up to 1.26 mM), whilst for Friedländer cyclization, a conversion over 95% within a retention time of only 20 min can be achieved by metal–organic-framework-decorated porous Cu catalyst. The utilization of dual metallic particles as printable inks offers valuable insights for fabricating hierarchical porous metallic structures for applications, such as advanced fixed-bed catalysts.

Stabilization/solidification (S/S) is an effective method used to reduce the leaching of heavy metals from soils, which is a serious environmental problem when soil is contaminated with heavy metals. In this study, a new stabilizing agent consisting of acetate-ethylene copolymer emulsion (VAE)-hydrated calcium silicate-polycarboxylate (V-CSH-PCE), water-soluble thiourea-formaldehyde (WTF) resins, cement, and fly ash was prepared for the solidification of heavy metal-contaminated soil under low-temperature conditions. The results showed that the agents significantly enhanced the compressive properties of the soil. When 10% cement, 8% fly ash, 1.5% V-CSH-PCE, and 0.5% WTF were added, the compressive strength of the subsoil after 1 day of curing was 0.3755 MPa, which was nearly 12 times higher compared with a blank sample. Meanwhile, the leaching concentrations of Cu2+, Zn2+, Pb2+, and Cr3+ in the substrate were 2.52, 1.12, 1.32, and 0.51 mg/L, respectively, which were lower than the leaching standard of “Hazardous Waste Identification Standard Leaching Toxicity Identification (GB 5085.3-2007)”. In addition, the compressive strength of the soil after 1 day of curing at a low temperature (4 °C) was 0.2915 MPa, which was 30.9% higher compared with the soil without the V-CSH-PCE. The results showed that the cement-fly ash-(V-CSH-PCE)-WTF mixture has good application prospects in improving the compressive strength of soil and stabilizing heavy metal ions.

Uranium is the most important fuel for nuclear power operations, and the safe supply of its resources is the key to the development of nuclear power in China. Because of the complex seawater environment and extremely low uranium concentration, extracting uranium from natural seawater poses a significant challenge. In this study, a polyamidoxime–phosphorylated cellulose nanofibril composite aerogel was prepared as an adsorbent for uranium extraction from seawater. An adsorption kinetics test, equilibrium adsorption isotherm model fitting, an adsorption–desorption cycle test, and a selectivity test were carried out to evaluate the adsorption performance of the composite aerogel for uranium extraction. The adsorption capacities for the initial concentrations of 4 and 8 ppm in uranium-spiked pure water were 96.9 and 204.3 mg-U/g-Ads, respectively. The equilibrium uranium adsorption capacities of uranium-spiked simulated seawater were 38.9 and 51.7 mg-U/g-Ads, respectively. The distribution coefficient KD of uranium was calculated to be 2.5 × 107 mL/g. The results show that the polyamidoxime–phosphorylated cellulose nanofiber composite aerogels prepared in this study have the advantages of low cost and high uranium selectivity for uranium extraction from seawater.

Summary: 3D or 4D printing of metal structures requires extreme conditions or a multistage process. Here, we present a protocol for the preparation of highly conductive metallic composites using liquid metal gels at ambient conditions. We describe the steps to prepare ternary gels composed of copper particles, liquid metal, and water. We then detail procedures for 3D or 4D printing gels into highly conductive structures after adding a small amount of rheological modifier (methyl cellulose) using direct ink writing techniques.For complete details on the use and execution of this protocol, please refer to Xing et al. (2023).1 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

Abstract The rice root-knot nematode (Meloidogyne graminicola) is one of the most destructive pests threatening rice (Oryza sativa L.) production in Asia; however, no rice resistance genes have been cloned. Here, we demonstrate that M. GRAMINICOLA-RESISTANCE GENE 1 (MG1), an R gene highly expressed at the site of nematode invasion, determines resistance against the nematode in several rice varieties. Introgressing MG1 into susceptible varieties increases resistance comparable to resistant varieties, for which the leucine-rich repeat domain is critical for recognizing root-knot nematode invasion. We also report transcriptome and cytological changes that are correlated with a rapid and robust response during the incompatible interaction that occurs in resistant rice upon nematode invasion. Furthermore, we identified a putative protease inhibitor that directly interacts with MG1 during MG1-mediated resistance. Our findings provide insight into the molecular basis of nematode resistance as well as valuable resources for developing rice varieties with improved nematode resistance.

Cellulose nanocrystals (CNC) are recognized as promising bio-based flocculants for controlling harmful algal blooms (HABs). Due to the charge shielding effect in seawater and the strong mobility of algae cells, CNC can’t effectively remove Phaeocystis globosa from seawater. To solve this problem, peroxymonosulfate (PMS) was used to enhance the coagulation of CNC for rapidly removal of P. globosa. The results showed that 91.7% of Chl-a, 95.2% of OD680, and 97.2% of turbidity of P. globosa were reduced within 3 h with the use of 200 mg L−1 of CNC and 20 mg L−1 of PMS. The removal of P. globosa was consisted of inactivation and flocculation. Notably, electron paramagnetic resonance (EPR) spectrums and quenching experiments revealed that the inactivation of P. globosa was dominated by PMS oxidation and 1O2. Subsequently, CNC entrained inactivated algal cells to settle to the bottom to achieve efficient removal of P. globosa. The content of total organic carbon (TOC) and chemical oxygen demand (COD) decreased significantly, indicating that a low emission risk of algal cell effluent was produced in the CNC-PMS system. In view of the excellent performance on P. globosa removal, we believe that the CNC-PMS system has great potential for HABs treatments.

Antibiotic residues have become a worldwide public safety issue. It is vital to detect multiple antibiotics simultaneously using sensors. A new and efficient method is proposed for the combined detection of two antibiotics (enrofloxacin (Enro) and ciprofloxacin (Cip)) in milk using surface plasmon resonance (SPR) sensors. Based on the principle of immunosuppression, two antibiotic antigens (for Enro and Cip) were immobilized on an optical fiber surface with conjugates of bovine serum albumin using dopamine (DA) polymerization. Each single antigen was bound to its corresponding antibody to derive standard curves for Enro and Cip. The fiber-optic sensor’s sensitivity was 2900 nm/RIU. Detection limits were calculated to be 1.20 ng/mL for Enro and 0.81 ng/mL for Cip. The actual system’s recovery rate was obtained by testing Enro and Cip in milk samples; enrofloxacin’s and ciprofloxacin’s mean recoveries from the milk samples were 96.46–120.46% and 96.74–126.9%, respectively. In addition, several different regeneration solutions were tested to analyze the two target analytes’ regeneration ability; NaOH and Gly-HCl solutions were found to have the best regeneration ability.

Rapid detection of marine oil spills is becoming increasingly critical in the face of frequent marine oil spills. Oil slick thickness measurement is critical in the hazard assessment of such oil leaks. As surface plasmon resonance (SPR) sensors are sensitive to slight changes in refractive index, they can monitor offshore oil spills arising from significant differences in the refractive index between oil and water. This study presents a gold-film fiber-optic surface plasmon resonance (FOSPR) sensor prepared by polydopamine accelerated wet chemical plating for rapid and real-time measurement of oil slick thickness. We examined oil thickness detection at two interfaces, namely, water-oil and air-oil. Detection sensitivity of −1.373%/mm is obtained at the water-oil interface in the thickness range of 0–5 mm; detection sensitivity of −2.742%/mm is obtained at the air-oil interface in the thickness range of 0–10 mm. Temperature and salinity present negligible effects on the oil slick thickness measurement. The fabricated FOSPR sensor has the ability to detect the presence of oil as well as quantify the oil thickness. It has favorable repeatability and reusability, demonstrating the significant potential for use in the estimation of marine oil slick thickness.

The Phaeocystis globosa widely exists in the seawater, which becomes a great threat for the health of humans and animals in the ecological ecosystem. In this work, we reported a promising control strategy with quercetin(QT) enhanced cellulose nanocrystals (CNC). The quercetin enhanced cellulose nanocrystals (QT/CNC) was characterized through Atomic Force Microscopy (AFM), Fourier Transform Infrared Spectrometer (FTIR) and X-ray diffractometer (XRD). The effects of concentrations of CNC and QT on controlled Phaeocystis globosa were investigated. The results showed that the removal rate of Phaeocystis globosa exhibited an optimal value (92.1 %) at 0.05 g L-1 CNC and 0.1 g L-1 QT. Furthermore, the chlorophyll-a content in the Phaeocystis globosa exhibited a remarkable decrease from 3.72 mg L-1 to 0.21 mg L-1 when QT/CNC was interacted. On the basis of these results, we concluded that Phaeocystis globosa could be removed by QT/CNC effectively. During the removal of Phaeocystis globosa, the pH of algal solution decreased from 9.45 to 7.36, indicating that QT/CNC could maintain the normal pH of water. In addition, the testing result of the QT/CNC zeta potentials was negative, which revealed that Phaeocystis globosa was removed through inhibition and flocculation. Accordingly, a possible removal mechanism of Phaeocystis globose by QT/CNC was presumed. This study suggested that QT/CNC might be a potential treatment materials on the removal of Phaeocystis globosa.

Calcium silicate hydrate-polycarboxylate (C-S-H-PCE) nanocomposites can greatly increase the hydration speed of cement paste. To obtain the optimal synthesis condition for smaller particle size, C-S-H-PCE was prepared by adding Ca(NO3)2(4H2O and Na2SiO3(5H2O solution into PCE dispersion solution under high speed stirring, and the effects of reaction temperature, drip flow rate, aging time, C-S-H content and molecular weight of PCE on the particle size distribution of C-S-H were studied. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) were employed to conduct the analysis of particle size and morphology of the prepared C-S-H-PCE. The application performance of the nano composite was characterized by testing the compressive strength of cement paste added with C-S-H-PCE. The experimental results showed that at 25 ?, C-S-H-PCE synthesized with lower PCE molecular weight, slower drip flow rate, and smaller C-S-H content had better performance. The compressive strength of cement paste with C-S-H-PCE cured under low temperature condition was tested. It turned out that the prepared nanocomposites can remarkably enhance the early strength of cement paste for up to 63.8 % and 24.2 % after 1 d and 3 d.

Thanks to the advantages of low disturbance, good concealment and high mobility, bionic fishes have been developed by many countries as equipment for underwater observation and data collection. However, differentiating between true and bionic fishes has become a challenging task. Commonly used acoustic and optical technologies have difficulty in differentiating bionic fishes from real ones due to their high similarity in shape, size, and camouflage ability. To solve this problem, this paper proposes a novel idea for bionic fish recognition based on blue-green light reflection, which is a powerful observation technique for underwater object detection. Blue-green light has good penetration under water and thus can be used as a signal carrier to recognize bionic fishes of different surface materials. Three types of surface materials representing bionic fishes, namely titanium alloy, carbon fiber, and nylon, are investigated in this paper. We collected 1620 groups of blue-green light reflection data of these three kinds of materials and for two real fishes. Following this, three machine learning algorithms were utilized for recognition among them. The recognition accuracy can reach up to about 92.22%, which demonstrates the satisfactory performance of our method. To the best of our knowledge, this is the first work to investigate bionic fish recognition from the perspective of surface material difference using blue-green light reflection.

Genetic association studies have discovered the GTF2I-NCF1 intergenic region as a strong susceptibility locus for multiple autoimmune disorders, with the missense mutation NCF1 rs201802880 as the causal polymorphism. In this work, we aimed to perform a comprehensive meta-analysis of the association of the GTF2I-NCF1 locus with various autoimmune diseases and to provide a systemic review on potential mechanisms underlying the effect of the causal NCF1 risk variants. The frequencies of the two most extensively investigated polymorphisms within the locus, GTF2I rs117026326 and NCF1 rs201802880, vary remarkably across the world, with the highest frequencies in East Asian populations. Meta-analysis showed that the GTF2I-NCF1 locus is significantly associated with primary Sjögren’s syndrome, systemic lupus erythematosus, systemic sclerosis, and neuromyelitis optica spectrum disorder. The causal NCF1 rs201802880 polymorphism leads to an amino acid substitution of p.Arg90His in the p47phox subunit of the phagocyte NADPH oxidase. The autoimmune disease risk His90 variant results in a reduced ROS production in phagocytes. Clinical and experimental evidence shows that the hypoactive His90 variant might contribute to the development of autoimmune disorders via multiple mechanisms, including impairing the clearance of apoptotic cells, regulating the mitochondria ROS-associated formation of neutrophil extracellular traps, promoting the activation and differentiation of autoreactive T cells, and enhancing type I IFN responses. In conclusion, the identification of the association of NCF1 with autoimmune disorders demonstrates that ROS is an essential regulator of immune tolerance and autoimmunity mediated disease manifestations.

Nanoplastics (NPs) are becoming an emerging pollutant of global concern. A potential risk of NPs is that they can serve as carriers and synergistically function with other contaminants to cause diseases. A variety of diseases such as Alzheimer’s disease are related to the generation of amyloid fibrils, and insulin is typically used as a model to study the fibrillation process. In this study, we examined the fibrillation of insulin promoted by polystyrene nanoplastics (PSNPs) alone and synergistically with organic contaminants (denoted as X, X = pyrene, bisphenol A, 2,2′,4,4′-tetrabromodiphenyl ether, 4,4′-dihydroxydiphenylmethane, or 4-nonylphenol) having different polarities using thioflavin T fluorescence assays, dynamic light scattering, and circular dichroism spectroscopy. The presence of PSNPs and small organic contaminants decreased the lag phase time (tlag) for insulin fibrillation from 54.6 h to 35-51 h and their combination (PS-X) enhanced this process (tlag = 21-30 h). Notably, the lag phase time for insulin fibrillation with PS-nonpolar contaminants, PS-weakly polar contaminants, and PS-polar contaminants is around 20.8, 26.7, and 30.1 h, respectively, indicating the synergistic effect of PS-nonpolar contaminants or PS-weakly polar contaminants was more obvious than that of PS-polar contaminants. Moreover, molecular dynamic simulation reveal the interactions between insulin and PSs or small organic contaminants are primarily driven by van der Waals forces and hydrophobic interactions. Overall, the findings of this study underscore the potentially significant environmental impact of small organic contaminants assisting NPs in promoting insulin fibrillation.

Detection of copper ions is important for environmental protection and human healthy. In this study, a ratiometric fluorescent probe was developed by using silica nanoparticles capped carbon dots (CDs) as the core and red quantum dots (CdTe) as the shell linking onto the surface of silica. Cu(II) was found to quench the fluorescence of red-emitting CdTe on the shell, while not changing the fluorescence of the core blue-emitting CDs embedding silica nanoparticles. Based on multiple spectroscopic studies, we propose that selective binding of Cu(II) to CdTe of CDs@SiO2-CdTe via a photoinduced electron transfer (PET) process. The as-proposed sensor allows selective determination of Cu(II) in the range from 0.82 µM to 25 µM, with a detection limit of 0.053 µM.

Hexavalent chromium (Cr(VI)) is one of the most toxic components in heavy metal pollution. The reduction of highly toxic Cr(VI) into much less toxic trivalent chromium (Cr(III)) is a promising and common method of remediating Cr(VI) contamination. Nanoscale zero-valent iron (nZVI) is an important nanoparticle to facilitate environmental remediation. It was reported on the fabrication of a bionanocomposite (nZVI@PGA), i.e. nZVI stabilized and modified by poly (?-glutamic acid) (PGA). The bionanocomposite was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The processes of Cr(VI) conversion by nZVI, PGA and nZVI@PGA were investigated and optimized. Compared to unmodified nZVI, nZVI@PGA displayed higher activity in acidic environment. The pH and PGA loading were optimized. The maximum unit removal of Cr(VI) by nZVI@PGA can reach 340 mg/g in acidic environment. The results demonstrated that nZVI@PGA can convert about 97.3 % Cr(VI) (initial concentration was 20 mg/L) in 30 min at pH=3. nZVI@PGA owns high stability and reactivity, and has potential to remove Cr(VI) of sewage in the future.

The membrane separation of oil/water emulsions has drawn much attention in recent years. The goal of present work is to develop a facile, cost-effective modification method to improve the hydrophilicity and antifouling of polyvinylidene fluoride (PVDF) membrane. Inspired by the plant polyphenol with strong anchoring ability on the various substrates, we report a two-step polyphenol chemistry strategy to achieve the hydrophobic-to-hydrophilic transformation of PVDF membrane via coordination assembly of tannic acid and Fe3+ ion followed by grafting of glutathione (GSH). The successful coating of GSH onto the PVDF membrane was confirmed by X-ray photoelectron spectroscopy. The modified PVDF membrane has good wettability (the water contact angle is 24.8 o and the underwater oil contact angle of 144.4 o) and high antifouling ability (the BSA rejection ratio is 87.7 %). More importantly, the modified membrane has a high water filtration flux up to 5,822 L m-2 h-1 at 0.09 MPa, and the separation efficiency is more than 99 % for the various surfactant stabilized oil-in-water emulsions. It is also successfully used to separate the high viscous crude oil-in-seawater emulsion, achieving a separation efficiency of > 95 %. The results showed that the simple and versatile method is promising for the modification of PVDF membranes with the ability of emulsion separation.

Vertical engineered barriers are often used to prevent the transport of heavy metal ions in groundwater, and barrier layers are the key to pollution control. In this study, modified calcium-based bentonite (CB) was prepared via the modification of CB with sodium carboxymethyl cellulose (CMC) and sodium hexametaphosphate (SHMP) for the prevention of heavy metal ions transport. CMC-SHMP@CB composites were prepared by pulping, drying and grinding. Structural characterization was performed by using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The swelling, permeability and adsorption properties of the CMC-SHMP@CB composites were further evaluated. The results show that these CMC-SHMP@CB composites have a hybrid microstructure from the intercalation and exfoliation action during modification. The swell index in deionized water of the CMC-SHMP@CB composites is 24.4 mL/2 g, which is 4.8 times that of the original CB index. Modification of CB with CMC and SHMP significantly improves its anti-permeation performance. In the presence of Cd2+ and Ni2+ ions, the hydraulic conductivity of the CMC-SHMP@CB composites still reaches ~ 3 × 10-11 m/s, which is much lower than the value of untreated CB. The adsorption capacity values of CMC-SHMP@CB for Ni2+ and Cd2+ were 11.01 mg/g and 13.82 mg/g, which are 5.6 times and 7.2 times the values before modification. CMC-SHMP@CB composites have great potential for use as the barrier layers for the prevention of heavy metal ions transport in groundwater.

In this study, the heavy metals contaminated sediments were from the sewage reservoir with an area of 850,000 m2. To measure the concentrations of heavy metals in sediments, 484 grid sampling points was set with a grid size of 40 m × 40 m. The sampling depth was in the range of 0.75 - 1.5 m. The concentrations of As, Cd, Cr6+, Cu, Pb, Hg, and Ni were then measured in the laboratory. Subsequently, the single factor index and Nemerow index method were used to evaluate the potential risk of heavy metals in sediments. The results show that the maximum Nemerow index is 12.6, which is mainly from the contribution of Hg, Cr6+, Cd, and As. The total contaminated sediments were calculated as 445,634 m3, of which 336,081 m3, 85,721 m3, 23,832 m3 are slightly polluted (1 < P = 2), moderately polluted (2 < P = 3) and heavily polluted (P > 3) sediments. The combined technology, integrating the dredging, stabilisation of heavy metals and flocculation in the pipeline, dewatering in geotextile tubes, are proposed for the treatment of sediments. After dewatering, the slightly and moderately polluted sediments were artificially constructed as a landfill for further landscape planting, while the heavily polluted sediments were sent to a cement plant for further treatment. After the implementation of the project from May to December 2019, all the heavy metals polluted sediments were treated well with high stability and low environmental risk.

Chlorophenols (CPs) are widely used in the industrial production of wood preservatives, herbicides, fungicides, and pesticides. Because of its widespread existence and low biodegradability, CPs have caused harm to the environment, ecology and human health. In this study, we report a dechlorination system for the rapid degradation of p-chlorophenol (p-CP), in which hydroxylamine hydrochloride (HAH) promotes the activation of sodium percarbonate (SPC) with ferrous ions (Fe2+). The effect of the different parameters, including the pH, temperature, concentrations of percarbonate and inorganic anions (Cl-, SO42-, NO3-) on the degradation of p-CP was investigated. The results show that the degradation efficiency reached 99 % with a HAH: Fe2+: SPC: p-CP molar ratio of 5:5:5:1 at 20 °C for 5 min. The free radicals quenching experiments were performed to identify active species. The results show that p-CP is mainly degraded by hydroxyl radicals (HO·) in the dechlorination system. This dechlorination system showed excellent degradation performance for the chlorophenols, making it to be a potential oxidant for treatment of the contaminated water.

Chlorinated compounds are widely used in the chemicals manufacturing industry. They have high toxicity and good stability, leading to the persistent pollution and damage of the ecological environment. In this study, p-chlorophenol (p-CP) was selected as the model, and a new dechlorination system was developed, that is, tannic acid (TA) and sodium hydroxide (NaOH) were used together to activate persulfate (PS). The effect of TA, NaOH, PS, and temperature on the degradation of chlorophenol was investigated. When 200 mg/L of TA, 0.4 M of NaOH and 100 mM of persulfate were used, the degradation efficiency of p-chlorophenol (50 mg/L) can reach 99 wt.%. There is no significant change in degradation efficiency when the reaction temperature is changed from 20 oC to 40 oC. The mechanism on the co-activation of persulfate with tannic acid and NaOH was proposed. The hydroxyl radicals and superoxide radicals play an important role in the degradation of p-CP. The dechlorination system showed excellent degradation performance for the chlorinated compounds, making it to be a potential oxidant for treatment of the contaminated groundwater.

Summary: Amyloid are protein aggregates formed by cross β structures assemblies. Inhibiting amyloid aggregation or facilitating its disassembly are considered to be two major effective therapeutic strategies in diseases involving peptide or protein fibrillation such Alzheimer's disease or diabetes. Using thioflavin-T fluorescence, far-UV circular dichroism spectroscopy, and atomic force microscopy, we found nontoxic and biocompatible black phosphorus quantum dots (BPQDs) appear to have an exceptional capacity to inhibit insulin aggregation and to disassemble formed mature fibrils, even at an ultralow concentration (100 ng/mL). The inhibition of fibrillation persists at all stages of insulin aggregation and increases PC12 cells survival when exposed to amyloid fibrils. Molecular dynamics simulations suggest that BPQDs are able to stabilize the α-helix structure of insulin and obliterate the β-sheet structure to promote the fibril formation. These characteristics make BPQDs be promising candidate in preventing amyloidosis, disease treatment, as well as in the storage and processing of insulin.

Abstract Background Biological pretreatment is an environmentally safe method for disrupting recalcitrant structures of lignocellulose and thereby improving their hydrolysis efficiency. Expansin and expansin-like proteins act synergistically with cellulases during hydrolysis. A systematic analysis of the adsorption behavior and mechanism of action of expansin family proteins can provide a basis for the development of highly efficient pretreatment methods for cellulosic substrates using expansins. Results Adsorption of Bacillus subtilis expansin (BsEXLX1) onto cellulose film under different conditions was monitored in real time using a quartz crystal microbalance with dissipation. A model was established to describe the adsorption of BsEXLX1 onto the film. High temperatures increased the initial adsorption rate while reducing the maximum amount of BsEXLX1 adsorbed onto the cellulose. Non-ionic surfactants (polyethylene glycol 4000 and Tween 80) at low concentrations enhanced BsEXLX1 adsorption; whereas, high concentrations had the opposite effect. However, sodium dodecyl sulfate inhibited adsorption at both low and high concentrations. We also investigated the structural changes of cellulose upon BsEXLX1 adsorption and found that BsEXLX1 adsorption decreased the crystallinity index, disrupted hydrogen bonding, and increased the surface area of cellulose, indicating greater accessibility of the substrate to the protein. Conclusions These results increase our understanding of the interaction between expansin and cellulose, and provide evidence for expansin treatment as a promising strategy to enhance enzymatic hydrolysis of lignocellulose.

Abstract Nanoscale zero-valent iron (nZVI) has shown considerable promise in the treatment of chlorinated organic compounds, but rapid aggregation and inactivation hinder its application. In this study, palladium-doped zero-valent iron nanoparticles involving poly (γ-glutamic acid) (Fe-Pd@PGA NPs) were synthesized. The nanoparticles were small (~100 nm), uniformly distributed, and highly stable. The dechlorination performance of Fe-Pd@PGA NPs was evaluated using p-CP as a model. The results demonstrated that Fe-Pd@PGA NPs show high activity even in weakly alkaline conditions. The maximum rate constant reached 0.331 min− 1 at pH 9.0 with a Fe to p-CP ratio of 100. Additionally, the dechlorination activity of Fe-Pd@PGA NPs is more than ten times higher than that of the bare Fe-Pd NPs, demonstrating the crucial role of PGA in this system. Furthermore, we investigated the dechlorination performance in the presence of different anions. The results indicated that Fe-Pd@PGA NPs can maintain high activity in the presence of Cl−, H2PO4 −, and humic acid, while HPO4 2−and HCO3 − ions slightly reduce the dechlorination activity. We believed that PGA is a promising stabilizer and promoter for Fe-Pd NPs and the Fe-Pd@PGA NPs have the potential for practical applications.

Abstract 4-Nitrophenol (4-NP) is a priority pollutant in water and is both carcinogenic and genotoxic to humans and wildlife even at very low concentrations. Thus, we herein fabricated a novel molecularly imprinted core-shell nanohybrid as a ratiometric fluorescent sensor for the highly sensitive and selective detection of 4-NP. This sensor was functioned by the transfer of fluorescence resonance energy between photoluminescent carbon dots (CDs) and 4-NP. This sensor was synthesized by linking organosilane-functionalized CDs to silica-coated CdSe quantum dots (CdSe@SiO2) via Si–O bonds. The nanohybrids were further modified by anchoring a molecularly imprinted polymer (MIP) layer on the ratiometric fluorescent sensor through a facile sol–gel polymerization method. The morphology, chemical structure, and optical properties of the resulting molecularly imprinted dual-emission fluorescent probe were characterized by transmission electron microscopy and spectroscopic analysis. The probe was then applied in the detection of 4-NP and exhibited good linearity between 0.051 and 13.7 μg/mL, in addition to a low detection limit of 0.026 μg/mL. Furthermore, the simplicity, reliability, high selectivity, and high sensitivity of the developed sensor demonstrate that the combination of MIPs and ratiometric fluorescence allows the preparation of excellent fluorescent sensors for the detection of trace or ultra-trace analytes.

Ultrathin 2-dimensional transition metal dichalcogenides (TMDs) have become a class of high-potential materials in biomedicine due to their intriguing properties. They have been applied to solve biomedical challenges, such as biosensing, bioimaging, drug delivery, and cancer therapy. However, studies of the interactions between these materials and biomolecules are insufficient. Mucous tissue serves as a barrier to foreign hazardous substances and a gel layer for substance exchange. The main organic matter of mucous tissue is mucin, so it was selected as a model biomolecule to study its interactions with six different TMD nanosheets (NSs), including single-layered (SL), few-layered (FL), and small few-layered (SFL) MoS2 and WS2 NSs, using quartz crystal microbalance (QCM) with a dissipation monitor (QCM-D) and surface plasmon resonance (SPR). Additionally, UV absorption, fluorescence, and circular dichroism (CD) spectroscopy were applied to investigate the mechanism of the interactions and to study the conformational change of mucin. We found that the TMD NSs could adsorb on the mucin layer and affect its viscoelasticity. The results indicated that the SL WS2 NSs exhibited the highest initial absorption rate and the maximum absorption amount, while the SL MoS2 NSs exhibited the highest initial desorption rate. During the adsorption, the viscoelasticity variations of the mucin layer caused by the WS2 nanosheets were weaker than those caused by the MoS2 nanosheets. Furthermore, the conformational changes of mucin caused by the SL MoS2, SL WS2, and SFL MoS2 NSs were higher than those resulting from other TMD NSs. These findings provide important information on the interactions between TMD NSs and mucin and provide useful insights into the interfacial behavior of TMD NSs before they enter tissues.

Ectopic expression of MHC II molecules on glandular cells is a feature of primary Sjögren's syndrome (pSS). However, the cause of this ectopic expression and its potential role in the pathogenesis of the disease remains elusive. Here, we report that ectopic expression of MHC II molecules on glandular cells represents an early presymptomatic event in a mouse model of pSS induced by immunization of Ro60_316-335 peptide emulsified in TiterMax® as an adjuvant. Ectopic expression of MHC II was induced by TiterMax® but not by complete freund's adjuvant (CFA). Furthermore, immunization with Ro60_316-335 peptide emulsified in TiterMax®, but not in CFA, induced a pSS-like disease in mice. Our results suggests that ectopic expression of MHC II molecules on glandular cells represents a presymptomatic feature of pSS and that such ectopic expression can be induced by exogenous factors. In addition, this study also provides a novel mechanism how adjuvants can amplify immune responses.

Palladium-doped nanoscale zerovalent iron nanoparticles (Fe-Pd NPs) was fabricated and stabilized by poly (γ-glutamic acid)–Dopamine composite (PGA-DA). The fabricated nanoparticles had high dechlorination activity towards p-Chlorophenol (p-CP). PGA-DA modified Fe-Pd NPs significantly outperformed PGA modified ones in catalytic activities even in weak alkaline condition. Fe-Pd NPs@PGA-DA (10 mg PGA-DA and 0.4 wt% Pd loading) could achieve 100 % p-CP removal within 60 min. It is worth mentioning that the presence of DA alone could overwhelm dechlorination capacity of Fe-Pd NPs toward p-CP. The coordination bonding between catechol and Fe ions was also investigated in detail. This study demonstrated that PGA-DA is a promising modifier and stabilizer for Fe-Pd NPs, which was expected to be applied in real environmental remediation technology.

The selective recognition of metal ions is very important and the development of novel chemosensor is still a challenge. Herein, a single dual-emissive fluorescence probe was developed to detect Fe3+ and phytic acid (PA). Red quantum dots (CdSe) were embedded into silica nanoparticles for an internal standard emission, whereas blue carbon dots (CDs) were covalently linked onto the surface of silica as a sensing element to achieve a more precise and sensitive detection. The fluorescence of the CDs was effectively quenched by Fe3+ via a photoinduced electron transfer (PET) process. Fe3+ could selectively bind to phytic acid, thus leading to the recovered fluorescence of the CDs in the presence of Fe3+. Upon addition of PA to the CdSe@SiO2-CDs/Fe(III) complex dispersion, the fluorescence of the CDs significantly increased. The ratiometric probe enabled the selective detection of PA within 0.08-1.6 mM and a limit of detection of 1.5 μM. Overall, this method provided high selectivity, stability, and recovery ratio in the detection of Fe3+ and PA.

Ochratoxin A (OTA) is a type of mycotoxin generated from the metabolism of Aspergillus and Penicillium, and is extremely toxic to humans, livestock, and poultry. However, traditional assays for the detection of OTA are expensive and complicated. Other than OTA aptamer, OTA itself at high concentration can also adsorb on the surface of gold nanoparticles (AuNPs), and further inhibit AuNPs salt aggregation. We herein report a new OTA assay by applying the localized surface plasmon resonance effect of AuNPs and their aggregates. The result obtained from only one single linear calibration curve is not reliable, and so we developed a “double calibration curve” method to address this issue and widen the OTA detection range. A number of other analytes were also examined, and the structural properties of analytes that bind with the AuNPs were further discussed. We found that various considerations must be taken into account in the detection of these analytes when applying AuNP aggregation-based methods due to their different binding strengths.

In this study, we developed a reflective localized surface plasmon resonance (LSPR) optical fiber sensor, based on silver nanoparticles (Ag NPs). To enhance the sensitivity of the LSPR optical sensor, two key parameters were optimized, the length of the sensing area and the coating time of the Ag NPs. A sensing length of 1.5 cm and a 1-h coating time proved to be suitable conditions to produce highly sensitive sensors for biosensing. The optimized sensor has a high refractive index sensitivity of 387 nm/RIU, which is much higher than that of other reported individual silver nanoparticles in solutions. Moreover, the sensor was further modified with antigen to act as a biosensor. Distinctive wavelength shifts were found after each surface modification step. In addition, the reflective LSPR optical fiber sensor has high reproducibility and stability.

Primary Sjögren’s syndrome (pSS) is characterized by a panel of autoantibodies, while it is not clear whether B cells and autoantibodies play an essential role in pathogenesis of the disease. Here, we report a novel mouse model for pSS which is induced by immunization with the Ro60_316-335 peptide containing a predominant T cell epitope. After immunization, mice developed several symptoms mimicking pSS, including a decreased secretion of tears, lymphocytic infiltration into the lacrimal glands, autoantibodies, and increased levels of inflammatory cytokines. Disease susceptibility to this novel mouse model varies among strains, where C3H/HeJ (H2-k) and C3H/HeN (H2-k) are susceptible while DBA/1 (H2-q) and C57BL/6 (H2-b) are resistant. Depletion of B cells using anti-CD20 monoclonal antibodies prevented C3H/HeN mice from development of the pSS-like disease. In addition, HLA-DRB1*0803, a pSS risk allele, was predicted to bind to the hRo60_308-328 which contains a predominant T cell epitope of human Ro60. Therefore, this study provides a novel mouse model for pSS and reveals an indispensable role of B cells in this model. Moreover, it suggests that T cell epitope within Ro60 antigen is potentially pathogenic for pSS.

OBJECTIVES:Anti-muscarinic acetylcholine type-3 receptor (anti-M3R) autoantibodies have been suggested to be pathogenic for primary Sjögren's syndrome (pSS), and the second extracellular loop of M3R is suspected to carry a disease-promoting epitope. In this study, we aimed to evaluate the pathogenicity of autoantibodies against peptides derived from the second extracellular loop of M3R in mice and to determine whether those autoantibodies could be used as biomarker for pSS. METHODS:BALB/c mice were immunized with modified linear or cyclic peptides of the second extracellular loop of M3R. The function of exocrine glands was evaluated by measuring the secretion of saliva and tears. The histological evaluations were performed by using H&E staining or direct immunofluorescence staining. Autoantibodies against linear or cyclic peptides of the second extracellular loop of M3R in human and mice were determined using ELISA. RESULTS:Immunization induced mice to produce autoantibodies against the linear or cyclic peptides of the second extracellular loop of M3R, and those autoantibodies could bind onto salivary glands. However, those mice showed neither impairment in the secretion of tears or saliva nor histological abnormality in the exocrine glands. Furthermore, passive transfer of the IgG isolated from the immunized mice into healthy mice did not induced the dysfunction of the exocrine glands. The prevalence of autoantibodies against the peptides of the second extracellular loop of M3R was low in pSS patients, and it did not differ significantly from that in healthy controls. CONCLUSIONS:Our results suggest that the autoantibodies against peptides of the second extracellular loop of M3R are not pathogenic in vivo and they are not suitable as biomarkers for pSS diagnosis.

Salvianolic acid B and rosmarinic acid are two main water-soluble active ingredients from Salvia miltiorrhiza with important pharmacological activities and clinical applications. The interactions between salvianolic acid B (or rosmarinic acid) and bovine serum albumin (BSA) in the presence and absence of gold nanoparticles (Au NPs) with three different sizes were investigated by using biophysical methods for the first time. Experimental results proved that two components quenched the fluorescence of BSA mainly through a static mechanism irrespective of the absence or presence of Au NPs. The presence of Au NPs decreased the binding constants of salvianolic acid B with BSA from 27.82% to 10.08%, while Au NPs increased the affinities of rosmarinic acid for BSA from 0.4% to 14.32%. The conformational change of BSA in the presence of Au NPs (caused by a noncompetitive binding between Au NPs and drugs at different albumin sites) induced changeable affinity and binding distance between drugs and BSA compared with no Au NPs. The competitive experiments revealed that the site I (subdomain IIA) of BSA was the primary binding site for salvianolic acid B and rosmarinic acid. Additionally, two compounds may induce conformational and micro-environmental changes of BSA. The results would provide valuable binding information between salvianolic acid B (or rosmarinic acid) and BSA, and also indicated that the Au NPs could alter the interaction mechanism and binding capability of drugs to BSA, which might be beneficial to understanding the pharmacokinetics and biological activities of the two drugs.

Context.--Recently, new technologies, such as nextgeneration sequencing and third-generation sequencing, have been used in carrier screening of thalassemia. However, there is no direct comparison between the 2 methods in carrier screening of thalassemia. Objective.--To compare the clinical performance of third-generation sequencing with next-generation sequencing in carrier screening of thalassemia. Design.--Next-generation sequencing and third-generation sequencing were simultaneously conducted for 1122 individuals in Hainan Province. Results.--Among 1122 genetic results, 1105 (98.48%) were concordant and 17 (1.52%) were discordant between the 2 methods. Among the 17 discordant results, 4 were common thalassemia variants, 9 were rare thalassemia variants, and 4 were variations with unknown pathogenicity. Sanger sequencing and polymerase chain reaction for discordant samples confirmed all the results of thirdgeneration sequencing. Among the 685 individuals with common and rare thalassemia variants detected by third-generation sequencing, 512 (74.74%) were carriers of athalassemia, 110 (16.06%) were carriers of b-thalassemia, and 63 (9.20%) had coinheritance of a-thalassemia and bthalassemia. Three thalassemia variants were reported for the first time in Hainan Province, including --THAI, -α2.4, and ααααanti3.7. Eleven variants with potential pathogenicity were identified in 36 patients with positive hemoglobin test results. Among 52 individuals with negative hemoglobin test results, 17 were identified with thalassemia variants. In total, third-generation sequencing and next-generation sequencing correctly detected 763 and 746 individuals with variants, respectively. Third-generation sequencing yielded a 2.28% (17 of 746) increment compared with next-generation sequencing. Conclusions.--Third-generation sequencing was demonstrated to be a more accurate and reliable approach in carrier screening of thalassemia compared with next-generation sequencing. [ABSTRACT FROM AUTHOR]

Ga-based liquid metal is an ideal matrix to dissolve and disperse other metal atoms for catalysis. Seawater electrolysis is a promising alternative technology for hydrogen production in the crisis of freshwater resources. Herein, we prepared a dynamic Co, Pt dual-atom synergistic catalyst by dispersing Co and Pt atoms in a Ga-based liquid metal (denoted as Ga-CoPt). Liquid Ga boosts the dispersion, mobility and synergy of Co and Pt atoms and leads to a dramatic increase in the catalytic performance for direct seawater electroreduction. Specifically, compared with solid Ga-CoPt, liquid Ga-CoPt shows much higher activity and stability in the hydrogen evolution reaction at 100 mA cm-2 for 169 h in natural seawater with a lower overpotential (249 mV at 10 mA cm-2) and Tafel slope (145 mV dec-1). Furthermore, atomically dispersed Co, Pt atoms in liquid Ga provide more active sites at the interface of Ga-CoPt under low contents of Co (5 wt%) and Pt (1 wt%). The fluidity of liquid Ga and the mobility of Co, Pt atoms enhance the replenishment and regeneration of active sites in liquid Ga-CoPt, which simultaneously promote the catalytic activity and stability. Moreover, the synergy of the Co and Pt atoms in liquid Ga is confirmed, with the Co atom as the active site for water splitting and some generated H species being adsorbed by the Pt atom to form H*. At the same time, the other generated H species are combined with adjacent H2O, generating H3O+. Subsequently, the adsorbed H* reacts with H3O+ to generate H2 via the Heyrovsky step. [ABSTRACT FROM AUTHOR]