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Much more attention has been paid to the contamination of Alternaria toxins because of food contamination and the threat to human health. In this study, an ultra‐high‐performance liquid chromatography‐tandem mass spectrometry method was developed for the simultaneous detection of the prototypical alternariol, alternariol monomethylether, and the metabolites 4‐oxhydryl alternariol, and alternariol monomethylether 3‐sulfate ammonium salt of Alternaria toxins. The positive samples were used as matrix samples to optimize the different experimental conditions. 0.01% formic acid solution and acetonitrile were used as the mobile phase, and analytes were scanned in negative electron spray ionization under multiple reaction monitoring, and quantitative determination by isotope internal standard method. Application of this method to samples of human plasma and urine showed the detection of the above analytes. The results showed that the recoveries were from 80.40% to 116.4%, intra‐day accuracy was between 0.6% and 8.0%, and inter‐day accuracy was between 1.1% and 12.1%. The limit of detection of the four analytes ranged from 0.02 to 0.6 µg/L in urine, and 0.02 to 0.5 µg/L in plasma, respectively. Thus, the developed method was rapid and accurate for the simultaneous detection of analytes and provided a theoretical basis for the risk assessment of Alternaria toxins for human exposure. [ABSTRACT FROM AUTHOR]

Greigite (Fe3S4), which have ferromagnetic in inverse thiospinel (AB2S4), is widely researched to use an adsorbent and biomedical field because non-toxicity and abundant in nature. Iron-based materials are known to have a high theoretical capacity because of their multivalent state including redox pairs, but still suffer from collapse and aggregate during the charge/discharge process. Here, the synthesized Fe3S4 nanosheet structure materials wrapped with reduced graphene oxide (Fe3S4NSs@rGO) were used as an anode electrode material for sodium-ion batteries (SIBs). The nano-sheet structure facilitates ion diffusion through expanded surface area, and rGO can effectively improve electrochemical conductivity and structure stability. As-prepared Fe3S4NSs@rGO were used as a host material to insert Na-ion via a conversion process, and the stabilized structure maintains the high capacity and long cycle performance. Thus, the Fe3S4NSs@rGO deliver a reversible capacity of 950 mAh g−1 after 200 cycles at a current density of 1A g−1 and 524 mAh g−1 after 400 cycles at a current density of 2A g−1, which is much higher than reported materials.

Using gas chromatography–tandem mass spectrometry and electrospun nanofibrous membrane, we developed and validated a simple, rapid, and sensitive methodology for quantifying eugenol residues in fish tissue and water samples. Fish tissue extract and water samples (315 samples) collected from three southeastern China provinces (Shanghai, Zhejiang, and Fujian), originating from eight provinces of Zhejiang, Jiangsu, Shandong, Guangdong, Fujian, Anhui, Shanghai, and Jiangxi, from April 2021 to April 2023 were filtered with an electrospun nanofiber membrane, extracted with trichloromethane/n-hexane, and directly concentrated to dry after simple purification. An internal standard of p-terphenyl in n-hexane and 5-µL injection volumes of the solutions was used to analyze eugenol via internal calibration with a minimum concentration of 0.5 µg/L in water samples and 0.1 µg/kg in aquatic product samples. The highest amount of eugenol was detected in Fujian province, possibly due to the higher temperature during transportation, while the lowest amount was found in Shanghai, which mainly uses temporary fish-culture devices. This is a fast, inexpensive, and effective method for testing large quantities of fish water and meat samples. [ABSTRACT FROM AUTHOR]

Natural proteins display organized hierarchical structures and tailored functionalities that cannot be achieved by synthetic approaches, highlighting the increased interest in developing protein‐based materials. Protein self‐assembly allows fabricating sophisticated supramolecular structures from relatively simple building blocks, a strategy naturally employed by amyloid proteins and intrinsically disordered proteins. However, the design of self‐assembled bioinspired materials with multi functionalities is still challenging. Inspired by the natural self‐assembly proteins (such as mussel foot proteins and amyloid proteins), a temperature‐inducible engineering programable hydrogel‐like amyloid nanostructure is developed by using a genetically modular fusion approach. The resulting hydrogel‐like assemblies display outstanding adhesive capacity, high stability, and broad substrate universality. The employed SpyCatcher/SpyTag system allows modifying the hydrogel‐like assemblies with any functional proteins of interest. Owing to their strong adhesive capacity and functional flexibility, such amyloid fibril‐based hydrogel shows advantages in the immobilization of diverse enzymes for highly efficient biocatalysis, fabrication of multi‐layered functional coatings, and construction of functionalized 3D scaffold for cell culture. Overall, a modular and straightforward approach is established to obtain a genetically programable nanostructure platform. The novel hydrogel‐like assemblies described here may be potentially applied to but not limited to synthetic biology, surface/interface engineering, and tissue engineering. [ABSTRACT FROM AUTHOR]

Dark carbon fixation (DCF), through which chemoautotrophs convert inorganic carbon to organic carbon, is recognized as a vital process of global carbon biogeochemical cycle. However, little is known about the response of DCF processes in estuarine and coastal waters to global warming. Using radiocarbon labelling method, the effects of temperature on the activity of chemoautotrophs were investigated in benthic water of the Yangtze estuarine and coastal areas. A dome‐shaped thermal response pattern was observed for DCF rates (i.e., reduced rates at lower or higher temperatures), with the optimum temperature (Topt) varying from about 21.9 to 32.0°C. Offshore sites showed lower Topt values and were more vulnerable to global warming compared with nearshore sites. Based on temperature seasonality of the study area, it was estimated that warming would accelerate DCF rate in winter and spring but inhibit DCF activity in summer and fall. However, at an annual scale, warming showed an overall promoting effect on DCF rates. Metagenomic analysis revealed that the dominant chemoautotrophic carbon fixation pathways in the nearshore area were Calvin‐Benson‐Bassham (CBB) cycle, while the offshore sites were co‐dominated by CBB and 3‐hydroxypropionate/4‐hydroxybutyrate cycles, which may explain the differential temperature response of DCF along the estuarine and coastal gradients. Our findings highlight the importance of incorporating DCF thermal response into biogeochemical models to accurately estimate the carbon sink potential of estuarine and coastal ecosystems in the context of global warming. [ABSTRACT FROM AUTHOR]

Carbon dots as new nanomaterials, have been widely used in rapid detection because of their nondestructive, real-time detection characteristics. Improving the sensitivity and selectivity of the method in complex real samples is new challenge and requirement for sensing technology. Here, we report an ultrasensitive fluorescence immunoassay (FIA) for trace diethyl phthalate (DEP) using red carbon dots@SiO2 (R-CDs@SiO2) as tags. SiO2 as a nanocarrier can effectively improve the bio-functionalization and utilization rate of carbon dots. Moreover, several R-CDs embedded in SiO2 nanospheres can magnify the fluorescence signal and improve sensitivity. R-CDs@SiO2 conjugate anti-DEP antibody (Ab) as fluorescent immunosensor, which can specifically recognize DEP. Under optimization conditions, the detection limit (LOD) of this FIA was calculated as 0.0011 ng/mL. In addition, the recoveries of this established FIA ranged from 96.8 to 108.5%, showing satisfactory accuracy. Compared with GC-MS/MS (LOD µg/mL), the sensitivity of the FIA was significantly improved. As a result, the FIA developed using R-CDs@SiO2 as tags has a high potential for determining trace DEP. [ABSTRACT FROM AUTHOR]

The filtration characteristics of low oil saturation reservoirs are obviously different from that of conventional reservoirs. The development performance and the influence factors for low oil saturation reservoirs were studied using laboratory large model physical modeling and reservoir numerical simulation, to match and establish the empirical formula of water cut variation. In the numerical stimulation process, the effect of threshold pressure on filtration for low permeability reservoirs was considered, which made the results more realistic. There wasn't a period of oil recovery without water for low oil saturation reservoirs; the water cut increased rapidly at the beginning, and dropped slightly before the period of oil production with stable water cut. The higher the initial water saturation, the shorter the production time with stable water cut. Recovery changed greatly with the injection/production pressure gradient when the injection/production pressure gradient was close to the pseudo threshold pressure gradient. Recovery changed little, even no change, with the injection/production pressure gradient when the injection/production pressure gradient was far larger than the pseudo threshold pressure gradient. There was a positive correlation between recovery degree and water injection rate when the injection/production pressure gradient was less than the pseudo threshold pressure gradient. Key words: low oil saturation reservoir, low permeability reservoir, pseudo threshold pressure gradient, filtration