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Genetic improvement of soybean oil content depends on in-depth study of the glycerolipid biosynthesis pathway. The first acylation reaction catalysed by glycerol-3-phosphate acyltransferase (GPAT) is the rate-limiting step of triacylglycerol biosynthesis. However, the genes encoding GPATs in soybean remain unknown.We used a novel yeast genetic complementation system and seed-specific heterologous expression to identify GmGPAT activity and molecular function in glycerolipid biosynthesis.Sixteen GmGPAT genes were cloned by reverse transcription-PCR for screening in yeast genetic complementation. The results showed that GmGPAT9-2 could restore the conditional lethal double knockout mutant strain ZAFU1, and GmGPAT1-1 exhibited low acyltransferase activity in serial dilution assays. In addition, the spatiotemporal expression pattern of GmGPAT9-2 exhibited tissue specificity in leaves, flowers and seeds at different developmental stages. Furthermore, both the proportion of arachidic acid and erucic acid were significantly elevated in Arabidopsis thaliana transgenic lines containing the seed-specific GmGPAT9-2 compared wild type, but the oil content was not affected.Together, our results provide reference data for future engineering of triacylglycerol biosynthesis and fatty acid composition improvement through GPATs in soybean.

Multiplexed nucleic acid sensing methods with high specificity are vital for clinical diagnostics and infectious disease control, especially in the postpandemic era. Nanopore sensing techniques have developed in the past two decades, offering versatile tools for biosensing while enabling highly sensitive analyte measurements at the single-molecule level. Here, we establish a nanopore sensor based on DNA dumbbell nanoswitches for multiplexed nucleic acid detection and bacterial identification. The DNA nanotechnology-based sensor switches from an "open" into a "closed" state when a target strand hybridizes to two sequence-specific sensing overhangs. The loop in the DNA pulls two groups of dumbbells together. The change in topology results in an easily recognized peak in the current trace. Simultaneous detection of four different sequences was achieved by assembling four DNA dumbbell nanoswitches on one carrier. The high specificity of the dumbbell nanoswitch was verified by distinguishing single base variants in DNA and RNA targets using four barcoded carriers in multiplexed measurements. By combining multiple dumbbell nanoswitches with barcoded DNA carriers, we identified different bacterial species even with high sequence similarity by detecting strain specific 16S ribosomal RNA (rRNA) fragments.

NiCo alloy particles (NiCo-APs)@hydrophilic carbon cloth (HCC) composites were successfully prepared by uniformly decorating magnetic NiCo-APs on the surface of three-dimensional HCC by employing an in-situ hydrothermal method. The NiCo-APs@HCC composites exhibited a unique corncob-like network structure that helped improve the electromagnetic wave (EMW) absorption performance of composites. The EMW absorption properties of the composites could be controlled by altering the Ni/Co molar ratio. The optimal minimum reflection loss (RL

High-performance mullite-based composite ceramics were prepared successfully using natural kaolin and alumina as raw materials and ZrO2 as an additive. The influence of sintering temperature and ZrO2 content on the sintering behaviour and mechanical properties of zirconia-toughened mullite ceramics was studied systematically. With increasing sintering temperature from 1450°C to 1560°C, the primary phases of as-sintered composite ceramics were mullite and corundum with a small amount of ZrO2, and the bulk density of the composite ceramics increased from 2.29 to 2.72 g cm–3. Furthermore, the ZrO2 phase transition promoted transgranular fracture, and ZrO2 grains were pinned at the grain boundaries, thereby enhancing the mechanical strength of the composite ceramics. Moreover, the AZS12 sample, with 12 wt.% ZrO2 and sintered at 1560°C, had the greatest flexural strength and fracture toughness of 91.6 MPa and 2.47 MPa m–1/2, respectively. Adding ZrO2 to the composite ceramics increased their flexural strength by ~37.6%.

DNA nanotechnology provides a unique opportunity for molecular computation, with strand displacement reactions enabling controllable reorganization of nanostructures. Additional DNA strand exchange strategies with high selectivity for input will enable novel complex systems including biosensing applications. Herein, we propose an autocatalytic strand displacement (ACSD) circuit: initiated by DNA breathing and accelerated by a seesaw catalytic reaction, ACSD ensures that only the correct base sequence starts the catalytic cycle. Analogous to an electronic circuit with a variable resistor, two ACSD reactions with different rates are connected in parallel to mimic a parallel circuit containing branches with different resistances. Finally, we introduce a multiplexed nanopore sensing platform to report the output results of a parallel path selection system at the single-molecule level. By combining the ACSD strategy with fast and sensitive single-molecule nanopore readout, a new generation of DNA-based computing tools is established.

Respiratory infections are the major cause of death from infectious disease worldwide. The clinical presentation of many respiratory viruses is indistinguishable; therefore, diagnostic approaches that can identify multiple pathogens are essential for patient management. We aimed to address this challenge with self-assembled DNA nanobait that can simultaneously identify multiple short RNA targets. The nanobait approach relies on specific target selection via toehold-mediated strand displacement and rapid read-out via nanopore sensing. Here, we show this platform can concurrently identify several common respiratory viruses, detecting a panel of short targets of viral nucleic acids from SARS-CoV-2, respiratory syncytial virus (RSV), rhinovirus, influenza, and parainfluenza. Our nanobait could be reprogrammed to discriminate viral variants, and we identified several key SARS-CoV-2 variants with single-nucleotide resolution. We increased assay specificity with bespoke nanobait that could identify numerous short RNA targets in the same viral sample in a complex background of the human transcriptome. Notably, we found that the sequence position in the viral RNA secondary structure is critical for nanobait design. Lastly, we show that nanobait could discriminate between samples extracted from oropharyngeal swabs from negative and positive SARS-CoV-2 patients using programmable target cleavage without pre-amplification. Our system allows for multiplexed identification of native RNA molecules, providing a new scalable approach for diagnostics of multiple respiratory viruses in a single assay.

The recognition of lumpish coal and gangue of different coal sorts was conducted using X-ray technique. Gas coal, fat coal and coking coal were used in this study, and the ash content was found to ...

Three-dimensional mesoporous lepidocrocite-type layered sodium titanate (LST) was constructed at room temperature by the electrostatic interaction between Ti1-δO24δ- nanosheets and Na+ ions. The results of a systematic X-ray diffraction investigation manifested the transition from the Ti1-δO24δ- nanosheets phase to the titanate/titania phase, which determined a phase diagram as a function of the temperature and NaCl concentration. In addition, scanning electron microscopy, inductively coupled plasma-mass spectrometry, thermogravimetric and differential thermal, N2 adsorption-desorption, Raman spectroscopy, Fourier transform infrared spectroscopy, as well as ζ-potential analyses were utilized for adequate characterization of the LST physical and chemical properties. Furthermore, batch adsorption experiments demonstrated that LST had superior adsorption property and adsorption selectivity toward cationic dyes compared to those of anionic dyes. A multifarious influencing effect on the cationic dye adsorption behavior during the adsorption process was systematically investigated. Moreover, the pseudo-second-order kinetic model felicitously depicted the cationic dye adsorption behavior through an elaborate kinetic study, namely, chemisorption was the main adsorption action. Meanwhile, different adsorption isotherm models were utilized to process the experimental data, uncovering that the adsorption isotherms of cationic dyes on LST were suitable for a Langmuir isothermal model. More importantly, an ion-exchange mechanism was proposed for the cationic dye adsorption on LST, and the ion-exchange reaction occurred with a stoichiometric exchange between 1 mol of Na+ ions in the LST interlayer and 1 mol of MB molecules in the solution. In parallel, the electrochemical impedance spectroscopy and cyclic voltammogram measurements verified that the high ionic conductivity of Na+ ions in the LST interlayer resulted in a superior adsorption property. A two-step acid-base procedure was ultimately adopted to effectively regenerate LST adsorbent. This work provides not only an alternative adsorbent with superior adsorption capacity and adsorption selectivity but also some guiding significance for research on the adsorption mechanism of layered titanates.

The high-ash tailings produced by flotation contains a large number of minerals that can be recycled. However, as the separation and purification technology for flotation tailings is not mature and separation efficiencies are low, it is generally treated as separation waste, resulting in the waste of mineral resources. In view of this phenomenon, the particle size composition and density composition of high-ash minerals in flotation tailings of coal slime as well as the type and content of mineral elements were measured. It was determined that the main mineral composition is quartz, and there is also a certain amount of chlorite (silicate mineral). A self-spinning hydrocyclone used for flotation tailings separation and purification was designed, and numerical simulation was carried out by fluent software. The internal flow field-, tangential velocity-, and axial velocity-distribution characteristics of the hydrocyclone at different rotational speeds were investigated. The physical model of the hydrocyclone was set up and the separation efficiency improvement test of fine particles was carried out. The results show that the overflow yield of −0.045 mm particles increased gradually with the increase in cylinder rotation speed. When the rotation speed increased to 900 r/min, the overflow yield of −0.045 mm particles can reach more than 90%, which can effectively realize the material classification according to 0.045 mm.

Construction of delicate nanostructures with a facile, mild-condition and economical method is a key issue for building high-performance electrode materials. We demonstrate a facile and novel "reassembling strategy" to hollow MnCoS nanospheres derived from dual-ZIF for supercapacitors. The spherical shell's surface structure, thickness and Mn distribution were controlled by regulating the solvothermal reaction time. The chemical composition, phases, specific surface areas and microstructure were studied and the electrochemical performances were systematically estimated. As the unique low-crystalline and optimized hollow nanosphere structure contributes to increasing active sites, MnCoS nanospheres exhibit excellent electrochemical performance. The test results show that the specific capacitance increases with increasing solvothermal time, and the MCS with a 5 h reaction time exhibits optimal electrochemical properties with a high specific capacity of 957 C g

Cyclophilins, a type of peptidyl-prolyl cis-trans isomerase, function as an important molecular chaperone in series of biological processes. However, the expression pattern and signal transduction pathway of cyclophilins is still unclear. Hereby, it was clarified that the promoter of OsCYP2 is a constitutive expression pattern which by GUS staining in transformants with pOsCYP2:GUS genetic transformation. Simultaneously, it is found that the sequence of promoter had not only core elements but also contained inducible elements. Then, the ABA responsive element was used to cDNA library screening, a transcription factor myc2-like was identified by yeast one hybrid and confirmed though electrophoretic mobility shift assay. Furthermore, the relative expression showed that myc2-like was induced by abscisic acid. In addition, myc2-like overexpression could enhance salt tolerance in transformants and partial restore cyp2-RNAi line. Together, we explored a novel transcriptional signal mediated by myc2-like, a potential regulator of salt stress physiological processes in rice.

The parameters of jet mixing devices have an important influence on the mixing process, particle movement and interface regulation. At present, jet mixing devices are widely used in the coal slime flotation field, and their variable parameters lack systematic optimization. In this paper, the performance of reagent mixing and the distribution characteristics of flow field are taken as the evaluation indexes, and computational fluid dynamics (CFD) software (FLUENT) is used to optimize the variable parameters of the device. The results show that when the area ratio Ar=1.96~3.24, the throat-nozzle distance Le=0.2Dh~0.6Dh, the suction tube is located 1/4~1/2 Lz to the left of the nozzle outlet and is symmetrically arranged, the length of the throat tube L is from 6Dz to 12Dz, the mixing performance of the jet mixing device was optimal. The flow field distribution characteristics showed that the area ratio has a more significant effect. The larger the area ratio is, the more favorable the mixing of the working fluid and the injection fluid is. The throat-nozzle distance has little effect on the flow field distribution, and its optimal value ranges from 0.3Dh to 0.6Dh. The fog droplet size test showed that the dispersion effect was the best when the area ratio Ar=3.24. The diameter size test of the injected bubbles was carried out to verify the performance of the jet mixing device after parameter optimization. The experimental results and the simulation results confirm each other, which proves the correctness of the numerical simulation results.

Fine kaolinite particles are mineral particles that are found in mine wastewater. The particles' shape is one of the parameters that causes a significant change in the sedimentation dynamics in water environments. In this work, experimental methods and Computational Fluid Dynamics - Discrete Element Method (CFD-DEM) methods served to investigate the dynamic characteristics of fine kaolinite particle sedimentation. The Results of statistical analyses show that the length-width ratio of fine kaolinite particles is 1–3 and the average simplified spherical coefficient is 0.625 in the 50–500 μm particle size range. The simplified spherical coefficient formula proved to be effective according to experimentation and simulations. Moreover, the effects of particle size, liquid viscosity, and liquid velocity on kaolinite particle sedimentation dynamic characteristics were numerically studied in detail by using the modified spherical coefficient. The simulation revealed that an increase in liquid viscosity resulted in a declining particle terminal velocity. However, the sensitivity of the particle terminal velocity affected by liquid viscosity fell when the particle size also declined. When an increase in particle size occurred, the sensitivity of the particle terminal velocity to the influence of upwelling water decreased.

Coal-derived carbon/Ni3Fe magnetic composites with frequency dependent microwave absorption performance were prepared at low temperatures (750–850 °C) using coal as the carbon source. The Ni3Fe alloy was successfully formed due to the carbothermal reaction and reducing gas. SEM images indicate the surface becomes rougher and the number of interlayer of the composites increases with increasing reaction temperature. Consistently, high degree of graphitization of the coal-derived carbon was confirmed by using Raman spectroscopy. Specifically, coal-derived carbon/Ni3Fe magnetic composites exhibit frequency-dependent microwave absorption characteristics at 2–18 GHz, that is, as the reaction temperature rises from 750 °C to 850 °C, the minimum reflection loss gradually shifts to low frequencies. Among them, CC/Ni3Fe(8 0 0)-0.4 exhibits a minimum reflection loss of −60.76 dB at 16.64 GHz, while the thickness is only 1.28 mm. Such a clean strategy provides experience for the environmental application of coal and microwave absorption. Meanwhile, a lightweight, stable and efficient microwave absorber has been developed.

A series of samples including leaf-like and rod-like rutile TiO2 nanoparticles with various facets exposed on the surface, parallelepiped-shaped anatase nanoparticles with [111] vertical facet exposed on the surface, irregular anatase nanoparticles, microsized six-point star-like anatase aggregates, and almond-like brookite aggregates had been hydrothermally synthesized from lepidocrocite-type layered titanate nanosheets. A systematical investigation was established to uncover the phase transition and morphological evolution from nanosheets to TiO2 polymorphs, and a phase diagram was determined by adjusting the synthesis parameters of the pH value and temperature. Two kinds of mechanisms composed of the dissolution-deposition process following Ostwald's ripening mechanism and the in situ topochemical conversion process following Ostwald's step rule had been proposed based on the time-dependent hydrothermal experiments. Briefly, the formation of the single-crystalline rutile phase appeared only at high temperatures with very low pH values, and similarly, the brookite phase strictly formed at high temperatures with a very high pH value. Nevertheless, the anatase phase could moderately appear in a wide range of temperatures and pH values. In addition, the single-crystalline rutile adopted a leaf-like morphology at low temperatures with high pH values and a rod-like morphology at high temperatures with low pH values, while the morphological evolution of anatase particles proceeded from irregular to parallelepiped-shaped and finally to six-point star-like morphology, and the crystal size was reduced from 1000 to 5 nm with decreasing pH values. Meanwhile, with the prolongation of the hydrothermal time, the layered titanate nanosheets first dissolved into the amorphous state and further converted into small anatase nanoparticles and finally to rutile or anatase nanoparticles based on the dissolution-deposition process, or the {010}-faceted layered titanate structure first converted into the [111]-vertical faceted anatase nanosheets by the topochemical transformation reaction and then split into the [111]-vertical faceted anatase nanoparticles. More importantly, the mesoporous [111]-vertical faceted anatase nanoparticles exhibited enhanced photocatalytic performance compared to that of Degussa P25, which was ascribed to its superior electronic band structure and effective charge separation. The systematical investigation in this work would be significant for consummating the preparation of the TiO2 polymorphs from layered titanate nanosheets and provided some reference values and guide schemes for the preparation of TiO2 nanoparticles with outstanding photocatalytic performance.

Nanopores are powerful single-molecule tools for label-free sensing of nanoscale molecules including DNA that can be used for building designed nanostructures and performing computations. Here, DNA hard drives (DNA-HDs) are introduced based on DNA nanotechnology and nanopore sensing as a rewritable molecular memory system, allowing for storing, operating, and reading data in the changeable three-dimensional structure of DNA. Writing and erasing data are significantly improved compared to previous molecular storage systems by employing controllable attachment and removal of molecules on a long double-stranded DNA. Data reading is achieved by detecting the single molecules at the millisecond time scale using nanopores. The DNA-HD also ensures secure data storage where the data can only be read after providing the correct physical molecular keys. Our approach allows for easy-writing and easy-reading, rewritable, and secure data storage toward a promising miniature scale integration for molecular data storage and computation.

Coal-based activated carbons (CACs) have excellent valuable applications, and have been industrially produced. However, ultra-fine coal-based activated carbons (UCACs) and their removal of methylene blue (MB) have rarely been reported in the present literature. Two kinds of UCACs were obtained in this paper and the adsorption test of MB was carried out. The adsorption performance of MB on UCAC was simulated by Grand Canonical Monte Carlo (GC-MC) method. The experimental results were validated by molecular simulation, and the adsorption mechanism was investigated. The adsorption amount of MB, the d50, and specific surface area values of the UCACnew (obtained by the new method) and UCACcm (obtained by the conventional chemical method) were 746.95 mg/g, 12.54 μm, 1225.36 m2/g and 652.77 mg/g, 12.10 μm, 713.76 m2/g, respectively. The results of the molecular simulation calculations were consistent with the pattern of magnitude of the experimental results. The peak of the adsorption concentration occurred near 6 Å on the pore surface. The interaction energy of MB molecules with carboxyl groups was much larger than with hydroxyl groups. Van der Waals forces dominated the adsorption process, with a contribution of >60% in both cases.

The increasingly electromagnetic wave (EMW) pollution has rendered the study and development of new, high-efficiency EMW absorbers a sought-after topic. In this study, graphite carbon nitride nanotubes/cobalt@carbon (GCNNs/Co@C) composites were fabricated using an in-situ synthesis method, which included facile grinding and carbonization pyrolysis. The synthesized GCNNs/Co@C composites exhibited a unique castor-fruit-like structure, that is, GCNNs formed an entwined three-dimensional (3D) network structure on the surface of cobalt@carbon (Co@C), which improved the EMW absorption properties of composites. The obtained GCNNs/Co@C composites exhibited excellent EMW absorption performance. For the fabricated GCNNs/Co@C composites, the minimum reflection loss (RL

Anion binding by receptor molecules is a central field of modern chemistry which impacts areas of catalysis as well as biological and materials chemistry. As binding often requires high chemical stability under aerobic and aqueous conditions for practical applications, carbon-based anion receptors have dominated this field, with main group element analogues receiving far less attention. The recent observation that the air- and moisture-stable amino-cyclophosph(V)azanes of the type [RN(E)P(μ-NR)]2 (E = O, S, Se) can exhibit halide binding that is competitive with topologically related organic receptors (such as squaramides and thioureas) has motivated us here to explore how the binding properties of phosphazane receptors can be enhanced further. Coordination of transition metals by the two P,N metal coordination sites of the phosph(III)azane dimer [(2-py)NHP(μ-NtBu)]2 not only activates the receptor for anion binding (by fixing the optimum exo-exo conformation and polarizing the endocyclic N-H substituents) but also stabilizes the P2N2 ring to hydrolysis and oxidation. We show how the binding properties of these receptors can be modulated by the coordinated metal fragments and that they can bind chloride 1 to 2 orders of magnitude stronger than the related squaramides and thioureas. These features can be utilized in anion transport through phospholipid bilayers under aqueous conditions for which transport can be improved by 1 order of magnitude compared to the previous best phosphazane and thiourea transporters. This study demonstrates how careful design of inorganic systems can result in potent supramolecular functionality, beyond that observed for organic counterparts.

Low matching thickness, broad effective absorption bandwidth (EAB, RL -10 dB) and excellent reflection loss (RL) are desirable properties for the advanced microwave absorption materials (MAMs). We synthesized novel interpenetrating structured rod-like nickel cobaltite (NiCo

While the solid-state nanopore shows increasing potential during sensitive and label-free single molecular analysis, target concentration and signal amplification method is in urgent need. In this article, a solution via designing a model nucleic acid circuit reaction that can produce "Y" shape-structure three-way DNA oligomers with controllable size and polymerization degree is proposed. Such a so-called lego-like three-way catalytic hairpin assembly (LK-3W-CHA) can provide both concentration amplification (via CHA circuit) and programmable size control (via lego-like building mode) to enhance spatiotemporal resolution in single molecular sensing of solid-state nanopore. Oligomers containing 1-4 DNA three-way junctions (Y monomers, Y1-Y4) are designed in proof-of-concept experiments and applications. When the oligomers are applied to direct translocation measurements, Y2-Y4 can significantly increase the signal resolution and stability than that of Y1. Meanwhile, Y1 to Y4 can be used as the tags on the long DNA carrier to provide very legible secondary signals for specific identification, multiple assays, and information storage. Compared with other possible tags, Y1-Y4 provides higher signal density and amplitude, and quasi-linear "inner reference" for each other, which may provide more systematic, reliable, and controllable experimental results.