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The design of workwear has significant effects on worker performance. However, the current workwear for coal miners in Northern China is poor in fitness and thermal comfort. In this study, new workwear (NEW) for coal miners was developed with the design features providing better cold protection and movement comfort performance, as compared with a commonly worn workwear (CON). To evaluate the effectiveness of NEW, we conducted human trials which were performed using simulated work movements (i.e., sitting, shoveling, squatting, and crawling) in a climate chamber (10°C, 75% RH). Physiological measurements and perceptual responses were obtained. The results demonstrated that the local skin temperatures at chest, scapula, thigh, and calf; mean skin temperatures,; and thermal comfort in NEW were significantly higher than those in CON. NEW also exerted an improvement in enhancing movement comfort. We conclude that NEW could meet well with the cold protective and mobility requirements.

Rotundic acid (RA), an ursane-type pentacyclic triterpene acid isolated from the dried barks of Ilex rotunda Thunb. (Aquifoliaceae), possesses diverse bioactivities. To further study its pharmacokinetics, a simple and sensitive liquid chromatography with triple quadrupole mass spectrometry (LC-QqQ-MS/MS) method was developed and validated to quantify RA concentration in rat plasma and tissue using etofesalamide as an internal standard (IS). Plasma and tissue samples were subjected to one-step protein precipitation. Chromatographic separation was achieved on a ZORBAX Eclipse XDB-C18 column (4.6 mm × 50 mm, 5 μm) under gradient conditions with eluents of methanol:acetonitrile (1:1, V/V) and 5 mM ammonium formate:methanol (9:1, V/V) at 0.5 mL/min. Multiple reaction monitoring transitions were performed at m/z 487.30 → 437.30 for RA and m/z 256.10 → 227.10 for IS in the negative mode. The developed LC-QqQ-MS/MS method exhibited good linearity (2–500 ng/mL) and was fully validated in accordance with U.S. Food and Drug Administration bioanalytical guidelines. Dose proportionality and bioavailability in rats were determined by comparing pharmacokinetic data after single oral (10, 20, and 40 mg/kg) and intravenous (10 mg/kg) administration of RA. Tissue distribution was studied following oral administration at 20 mg/kg. The results showed that the absolute bioavailability of RA after administration at different doses ranged from 16.1% to 19.4%. RA was rapidly absorbed in a dose-dependent manner and highly distributed in the liver. In conclusion, this study is the first to systematically elucidate the absorption and distribution characteristics of RA in rats, which could provide additional information for further development and evaluation of RA in drug metabolism and pharmacokinetic studies.

The embryo in maize has a critical role in controlling kernel nutrition components and grain yield. We measured five embryo weight and size traits, six kernel weight and size traits, and five embryo-to-kernel ratio traits in a nested association mapping (NAM) population of 611 recombinant inbred lines (RILs) derived from four inbred lines including the high-oil, giant-embryo line BY815 as the common parent. Using three statistical methods, we identified 5–22 quantitative trait loci (QTL) for each trait, explaining 4.7%–46.7% of the phenotypic variation. The genetic architecture of maize embryo size and its related traits appeared to be dominated by multiple small-effect loci with little epistasis, and the genetic control underlying embryo size appeared to be distinct from that underlying kernel size. A trait–QTL association network included 205 nodes and 439 edges and revealed 28 key loci associated with at least three traits. Cloned maize genes including ZmUrb2, Emp12 and ZmBAM1d, maize orthologs of known rice genes that control seed size including BG1, XIAO and GS9, and 11 maize orthologs of Arabidopsis EMBRYO-DEFECTIVE (EMB) genes were identified as underlying these key loci. Further, the phenotypic and genetic relationships between embryo size and kernel size were evaluated, and genetic patterns for identified loci that control embryo size and its related traits were proposed. Our findings reveal distinct genetic architectures for embryo size, kernel size, and embryo-to-kernel ratio traits and establish a foundation for the improvement of embryo-size-mediated kernel nutrition and grain yield.

In K4750 alloy, the evolution of grain boundary (GB) precipitates, including the degradation of blocky MC carbide particles and the precipitation of granular/needle-like η phase particles, were observed after long-term aging (LA) at 750°C for 8000 h. During MC degradation, the Ti and C released from the MC carbide combined with Ni and Cr, respectively, in the γ matrix to form η-Ni3Ti phase and Cr-rich M23C6 carbide. Large amounts of granular η phase precipitated at GBs and the needle-like η phase grew gradually from GBs toward the grain interior. Because of the growth of the η phase through absorbing γ′ phase, γ′-depleted zones were formed around the η phase. The evolution of the MC carbide and η phase was primarily responsible for the decrease of the stress rupture life and the increase of elongation. After an LA sample was tested at 750°C and 360 MPa, the residual strain distribution was investigated by electron backscatter diffraction (EBSD). The results showed that the residual strain mainly distributed at GBs, especially in the region of MC degradation and at the edges of η phases, which was closely related to the appearance of phase interfaces. Microvoids/cracks easily initiated at phase interfaces, then easily extended along the γ′-depleted zones, thus the stress rupture life of LA samples was substantially shorter than that of samples subjected to the standard treatment. In particular, because of large amounts of fine degraded MC, granular M23C6 and granular η phase particles distributed at GBs after 750°C /8000 h LA and microvoid/crack formation could be hindered by the formation of dimples, which led to an increase of elongation.

In this paper, an adaptive element free Galerkin (EFG) method is presented to solve Poisson equation. In general, element free Galerkin method using moving least square (MLS) approximation needs a background mesh for integration. With the arbitrary polygonal influence domain technique, the shape function of MLS has almost interpolation property, and the Gaussian quadrature points in the background integration element only contribute to the vertices of that element, which enables us to compute the residual based on the background integration element just like the finite element method (FEM). The adaptive procedure based on triangular or tetrahedral background integration elements is then developed for EFG method, in which the residual-based a posteriori error estimation of FEM is used. Numerical examples are provided to illustrate the efficiency of the proposed adaptive EFG method.

To substantially prevent electromagnetic threatens, microwave absorbing materials (MAMs) are required to eliminate surplus electromagnetic waves. As a typical MAM, Fe3O4 particles with complex permittivity and permeability have been widely applied due to the coexistence of magnetic loss and dielectric loss. However, the necessary high mass fraction significantly limited its applications, thus Fe3O4 nanostructures have been extensively investigated to overcome this problem. In this work, uniform Fe3O4 nanobelts were prepared by electrospinning and two-step thermal treatment. By controlling the composition and viscosity of the electrospinning precursor solution, Fe3O4 nanobelts with tunable lateral sizes (200 nm–1 μm) were obtained. The samples with low content (only 16.7 wt%) Fe3O4 exhibited wide maximum effective absorbing bandwidths (EAB) over 3 GHz, and Fe3O4 nanobelts with smaller lateral sizes showed a maximum EAB of 4.93 GHz. Meanwhile, Fe3O4 nanobelts with smaller lateral sizes presented superior reflection loss properties, the lowest reflection loss reached −53.93 dB at 10.10 GHz, while the maximum EAB was up to 2.98 GHz. The excellent microwave reflection loss of Fe3O4 nanobelts was contributed to the enhanced synergistic effect of magnetic loss, dielectric loss, and impedance matching, originated from the hierarchically cross-linked networks and shape anisotropies. This study could broaden the practical applications of magnetic absorbers, and provided an approach for the development of shape anisotropic magnetic materials.

The Intensive Supervision Mechanism (hereafter referred to as ISM) is one of the most important institutional management innovations for air pollution control in China, but there is currently no consensus on the effects of the ISM on air quality improvement. In this study, a reliable quantitative model based on the Difference-in-Differences (DID) analysis was designed to evaluate the impacts of ISM on air quality (as indicated by good air quality days (hereafter referred to as GAD) and the concentrations of six major air pollutants (i.e. PM

Electroencephalography (EEG) provides appealing biometrics by encompassing unique attributes including robustness against forgery, privacy compliance, and aliveness detection. Among the main challenges in deploying EEG biometric systems in real-world applications, stability and usability are two important ones. They respectively reflect the capacity of the system to provide stable performance within and across different states, and the ease of use of the system. Previous studies indicate that the usability of an EEG biometric system is largely affected by the number of electrodes and reducing channel density is an effective way to enhance usability. However, it is still unclear what is the impact of channel density on recognition performance and stability. This study examines this issue for systems using different feature extraction and classification methods. Our results reveal a trade-off between channel density and stability. With low-density EEG, the recognition accuracy and stability are compromised to varying degrees. Based on the analysis, we propose a framework that integrates channel density augmentation, functional connectivity estimation and deep learning models for practical and stable EEG biometric systems. The framework helps to improve the stability of EEG biometric systems that use consumer-grade low channel density devices, while retaining the advantages of high usability.

The ionosphere characteristics are important for radio propagation and to monitor climate. At present, its research is confined to global scale or a single station. There are only few local area studies of ionosphere. In view of this situation, we will first verify the reliability of Global Ionosphere Map (GIM, IGS final products) in the Qinghai–Tibet Plateau, then implement low-power filtering and time series analysis to study the periodic, semiannual, and seasonal variation, the peak characteristic, and the “winter anomaly” phenomenon of the ionosphere. Finally, correlations between total electron content (TEC), solar activity indices, and geomagnetic indices are investigated, respectively, by executing quadratic polynomial fitting and establishing the relationship of TEC and F10.7p. The experimental results show that GIM is a reliable resource to research on the temporal and spatial characteristics of the ionosphere in the Qinghai–Tibet Plateau. The minimum TEC always occurs in autumn, whereas the maximum TEC occurs in spring or winter alternatively, which depends on the ascending or descending phase of solar activity. The “winter anomaly” phenomenon that existed for few years normally appears during the ascending phase of solar activity. The correlation coefficients of TEC with three solar activity indices, sunspot number, F10.7, and F10.7p are 0.79, 0.82, and 0.83, respectively, which show strong correlations between them. The correlation coefficients of TEC with three geomagnetic indices, Dst, Kp, and Ap are −0.48, 0.43, and 0.38, respectively, which show weak correlations between them. Quadratic polynomial regression of F10.7p and TEC is implemented. The regression line reflects that the ionosphere TEC in the Qinghai–Tibet Plateau has a saturated status.

Aurantinins (ARTs) are antibacterial polyketides featuring a unique 6/7/8/5-fused tetracyclic ring system and a triene side chain with a carboxyl terminus. Here we identify the art gene cluster and dissect ART’s C-methyl incorporation patterns to study its biosynthesis. During this process, an apparently redundant methyltransferase Art28 was characterized as a malonyl-acyl carrier protein O-methyltransferase, which represents an unusual on-line methyl esterification initiation strategy for polyketide biosynthesis. The methyl ester bond introduced by Art28 is kept until the last step of ART biosynthesis, in which it is hydrolyzed by Art9 to convert inactive ART 9B to active ART B. The cryptic reactions catalyzed by Art28 and Art9 represent a protecting group biosynthetic logic to render the ART carboxyl terminus inert to unwanted side reactions and to protect producing organisms from toxic ART intermediates. Further analyses revealed a wide distribution of this initiation strategy for polyketide biosynthesis in various bacteria., Aurantinins are polyketides with unusual connectivities and broad antibacterial activity. Here the authors show the biosynthesis of aurantinins, which proceeds via an on-line methyl esterification at the terminus that enables the iterative chain elongations prior to condensation and cyclization.

Hyperspectral images collected by unmanned aerial vehicles (UAVs) can provide fine, narrowband spectral information and help realize the accurate estimation of physiological and biochemical crop pa...

The barium ferrite BaFe12O19 with c-plane anisotropy, which possessed relative high saturation magnetization and low coercivity, had been synthesized by hydrothermal method with different reaction time of 5 h, 8 h,11 h,14 h, and 17 h. The X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and vibrating sample magnetometer (VSM) were used to study the phase composition, microstructure and magnetic properties of barium ferrite, respectively. The results showed the intensities of the peak were enhanced and there was no impurity phase. With the prolonging of the reaction time to 11 h, 14 h and 17 h, the grain size increased, and the equivalent diameter was about 1 μm, and the thickness was about 100 nm. When the reaction time was 17 h，the coercivity of barium ferrite was 1104 Oe. The reduction of coercivity was ascribed to the increase of particle size and the reduction in magnetic anisotropy.

Producing renewable biofuels from biomass is a promising way to meet future energy demand. Here, we demonstrated a lignin to diesel route via dimerization of the lignin oil followed by hydrodeoxygenation. The lignin oil undergoes C-C bond dehydrogenative coupling over Au/CdS photocatalyst under visible light irradiation, co-generating diesel precursors and hydrogen. The Au nanoparticles loaded on CdS can effectively restrain the recombination of photogenerated electrons and holes, thus improving the efficiency of the dimerization reaction. About 2.4 mmol gcatal-1 h-1 dimers and 1.6 mmol gcatal-1 h-1 H2 were generated over Au/CdS, which is about 12 and 6.5 times over CdS, respectively. The diesel precursors are finally converted into C16-C18 cycloalkanes or aromatics via hydrodeoxygenation reaction using Pd/C or porous CoMoS catalyst, respectively. The conversion of pine sawdust to diesel was performed to demonstrate the feasibility of the lignin-to-diesel route.

Lateral–directional stability is a critical issue for the design of any kind of aircraft. For the hypersonic waverider, the nonaxisymmetric, flat, and slender geometric feature makes it susceptible...

The serious destruction of resources and environment in Laizhou Bay has attracted extensive attention of researchers. This study mainly analysed the changes of fish structure and environment in the coastal zone of Laizhou Bay caused by human activities. By consulting literatures and field measurements, the changes of dominant fish species, coastline and sea water intrusion were analysed. The results showed that dominant fish species in Laizhou Bay change from high-economic species to low-economic species under the influence of human activities, and the coastline erosion was serious, and the area of sea water intrusion was also increasing year by year. It is concluded from the research results that human activities had a significant impact on the structure of fish school and the environment. It is necessary to arrange human activities in an appropriate amount to reduce the overexploitation of resources in order to restore the fishery resources and environment in Laizhou Bay.

A new porous copper-organic framework assembled from 12-nuclear [Cu12] nanocages {[Cu2(L4-)(H2O)2]·4DMA·2H2O}n (1) (H4L = 5,5'-(butane-1,4-diyl)-bis(oxy)-diisophthalic acid) was successfully prepared and structurally characterized. Compound 1 feathering of a 3D framework with two types of 1D nanotubular channels and a large specific surface area can effectively enrich various harmful dyes. Additionally, due to the carbon dioxide (CO2) interactions with open Cu(II) sites and the electron-rich ether oxygen atoms of ligand in 1, it exhibits a highly selective CO2 uptake. Interestingly, 1 can effectively catalyze the cycloaddition reaction of CO2 with various epoxides under mild conditions, which is ascribed to the Lewis acid Cu(II) sites in the framework of 1. Importantly, 1 acting as a heterogeneous catalyst can be recycled at least 10 times without an obvious loss of catalytic activity, and the CO2 cycloaddition mechanism was further uncovered by density functional theory (DFT) calculations. This study can greatly enrich the MOF catalysts system of CO2 conversion and also provide a valuable guidance for the design of efficient MOFs catalysts.

A solid-state repetition linear transformer driver (LTD) for a high-power microwave (HPM) driver is constructed, comprising a total of 50 stage-series structures, with each stage possessing eight parallel bricks. This article describes the primary and secondary circuit differences between a driving source and a modern LTD, as well as analyzing the influence of load impedance on system efficiency in a simplified circuit of the LTD using a Laplace transform. This article also examines the optimum load impedance for a given magnetic core and primary circuit. The current load impedance of one stage is $2~\Omega $ , and the corresponding system efficiency is 95%. A real-time control and triggering system are developed. A trigger transformer with a 100-channel pulse output is designed. The output voltage of the constructed driving source is about 500 kV, the current is 5 kA, the pulsewidth is about 125 ns, and the output power is 2.5 GW. The driving source can work at a repetition rate of 50 Hz. The driving source will drive a low magnetic field relativistic backward-wave oscillator to generate HPMs.

Controlling Vacancies and heterointerfaces of nano/microstuctures is very challenging, importantly, which tailors the electromagnetic (EM) parameters to develop the high-performance electromagnetic wave (EMW) absorbers. Herein, we report a strategy using various sulfur-source modifying Fe3O4 nanosphere by one-step hydrothermal method to prepare a series of FeS2-based composites. Diverse sulfur sources determine their morphologies, crystal structures and compositions, and further affect EMW absorption abilities. Among these materials, rich sulfur vacancies and abundant heterogeneous interfaces improve their conduction loss and polarization loss caused by a unique concave cubic polyhedrons structure of the Fe3O4/FeS2 composites fabricated by thioacetamide (TAA), which displays the brilliant EMW absorption capacity compared to others. That is, it possesses the minimum reflection loss (RLmin) of −59.27 dB and effective absorption bandwidth (EAB, RL ≤ -10 dB) of 5.86 GHz at the thin thickness of 1.8 mm. This study opens a new avenue for designing the superior EMW absorbers by tunable sulfur vacancy and heterointerface.

Rice is an important staple food for more than half of the global population and one of the largest water consumers on earth. Improving the efficiency of water embedded in rice production and supply could have great implications for food and water security. This study starts from Yunnan, a traditional rice producing and consuming province in southwest China, and analyses its rice supply structure and dynamics, together with embedded water footprints (WFs) of three other regions: Northeast China, South and Southwest China and Southeast Asia. The results show that Yunnan has been through drastic food change in the past decades, leading to an increasing production and supply gap. Yunnan is found to have the least WF (778.2 m3/t) for rice production across the study regions, while Northeast China consumes the highest blue WF (364.6 m3/t) and blue to total WF ratio (97.7%). The study indicates that Northeast China is at risk of groundwater deficit due to rice production and export and the current rice production and consumption pattern is inefficient. The study suggests that policies for groundwater extraction, water resource price and international trade need to be in place to ensure sustainable food supply and water use at regional and national levels. Highlights Yunnan's rice supply and its water footprint from different transboundary regions are analyzed from the food-water nexus perspective.; Rice supply in Yunnan is found to have a cascading effect on water security in Northeast China, and the current rice supply paradigm could be both unsustainable and inefficient for water use.; This study shows the incremental needs to manage groundwater use and adjust the trading policy in China.

Summary Starch is the most abundant storage carbohydrate in maize kernels and provides calories for humans and other animals as well as raw materials for various industrial applications. Decoding the genetic basis of natural variation in kernel starch content is needed to manipulate starch quantity and quality via molecular breeding to meet future needs. Here, we identified 50 unique single quantitative trait loci (QTLs) for starch content with 18 novel QTLs via single linkage mapping, joint linkage mapping and a genome‐wide association study in a multi‐parent population containing six recombinant inbred line populations. Only five QTLs explained over 10% of phenotypic variation in single populations. In addition to a few large‐effect and many small‐effect additive QTLs, limited pairs of epistatic QTLs also contributed to the genetic basis of the variation in kernel starch content. A regional association study identified five non‐starch‐pathway genes that were the causal candidate genes underlying the identified QTLs for starch content. The pathway‐driven analysis identified ZmTPS9, which encodes a trehalose‐6‐phosphate synthase in the trehalose pathway, as the causal gene for the QTL qSTA4−2, which was detected by all three statistical analyses. Knockout of ZmTPS9 increased kernel starch content and, in turn, kernel weight in maize, suggesting potential applications for ZmTPS9 in maize starch and yield improvement. These findings extend our knowledge about the genetic basis of starch content in maize kernels and provide valuable information for maize genetic improvement of starch quantity and quality.

Layered O3-phase LiNi0.8Co0.1Mn0.1O2 (NCM811) material has shown great potential for lithium-ion batteries (LIBs). However, capacity attenuation and irreversible phase transitions have been serious...

Sustainable agriculture requires nutrient management options that can increase crop yields that are profitable for N nutrient availability and are environmentally friendly. However, N nutrient is dynamic and easy to lose, and excessive use of chemical N fertilizers has a negative impact on the environment. Biofertilizer by rhizobacteria is an effective way to maintain a reliable N-supply for rice growth. This study investigates the effect of a different combination of rhizobacterial fertilizers on nitrogen ion concentration in the soil and total rice production. The field experiment was conducted in two seasons. There were three treatments, including PGPR with 25% CF, PGPR with 50% CF, and 100% CF. The soil sample was taken from each treatment in six growth stages of rice i.e. 15, 36, 50, 72, 100, and 118 days after transplanting. Soil chemicals NH4+ and NO3- were analyzed by Ion Chromatography. The results showed that the uniformity of NH4+ and NO3- in the soil were the highest in fertilizer application with PGPR. The application of PGPR with 50% CF confirms that it can increase rice yields by 25.5% and 12.9%, respectively. The application of rhizobacteria can reduce the use of chemical fertilizers.

We fabricated a conductive whisker carbon nanotube (CNT) film by a simplified Langmuir−Blodgett method in which loose whisker CNTs (WCNTs) were densified via a capillary-induced compression assisted by a porous sponge. After this densification treatment, WCNTs formed conductive networks. The deformation of WCNT networks can cause a significant resistance change. The electric resistance of conductive WCNT network is highly sensitive to external mechanical stimuli. We developed a flexible and stretchable WCNT-based strain sensor using WCNT film sandwiched between two pieces of elastic polydimethylsiloxane films. This WCNT-based sensor exhibits an extremely high sensitivity (up to a gauge factor of 4839) over a wide strain range, fast response (60 ms), the good stability of mechanical cycling (1000 cycles), and extremely wide response window (it can detect strains as low as 0.05% and up to 420%). The WCNT-based sensing devices are able to monitor human muscle activity ranging from vital signs to high-strain human joint motions due to their high sensitivity and wide strain sensing range.

The relationship among B content, microstructure evolution and stress rupture properties of K4750 alloy during long-term aging were investigated. After aging at 800 ℃ for 1000 h, the decomposition degree of MC carbides of K4750 alloys with 0B, 0.007 wt. % B and 0.010 wt. % B were basically identical, which indicated that B has no inhibition on MC carbide decomposition during long-term aging. The MC carbide decomposition was accompanied by the formation of M23C6 carbides and a small number of η phases, which was controlled by the outward diffusion of C and Ti combined with the inward diffusion of Ni and Cr from the γ matrix. In addition, M23C6 carbides in boron-free alloy were in continuous chain and needle-like η phases were precipitated near them, while M23C6 carbides in boron-containing alloys remained in granular distribution and no η phases precipitation around them. Adding B could delay the agglomeration and coarsening of M23C6 carbides during long-term aging, which was because the segregation of B at grain boundary retarded the diffusion of alloy elements, thus weakened the local fluctuation of chemical composition near grain boundary. The stress rupture samples of K4750 alloys with various B contents after aging at 800 ℃ for 1000 h were tested at 750 ℃/380 MPa. The results indicated that the stress rupture properties of boron-containing alloys were significantly better than that of boron-free alloy, which could be attributed to the increase of grain boundary cohesion strength and the optimization of M23C6 carbide distribution due to the addition of B.

Photocatalytic biomass conversion represents an ideal way of generating syngas because of the sustainable use of biomass carbon and solar energy. However, the lack of efficient electron-proton transfer limits its efficiency. We here report an unprecedented method to simultaneously increase both the electron and proton transfer by creating surface sulfate ions on the CdS catalyst ([SO4]/CdS). Surface sulfate ion [SO4] is bifunctional, serving as the proton acceptor to promote proton transfer, and increasing the oxidation potential of the valence band to enhance electron transfer. [SO4]/CdS produces a syngas mixture from glycerol without CO2. Compared with pristine CdS, [SO4]/CdS exhibits 9-fold higher CO generation rate (0.31 mmol g-1 h-1) and 4-fold higher H2 generation (0.05 mmol g-1 h-1). A wide range of sugars, such as glucose, fructose, maltose, sucrose, xylose, lactose, insulin, and starch, were facilely converted into syngas. This study reports the pivotal effect of surface sulfate ion on electron-proton transfer in photocatalysis and provides a facile method for increasing photocatalytic efficiency.

For intracellular molecular detection, the appropriate probes should include the abilities to enter target cells noninvasively, target specific sites, and then respond to the analytes reliably. Herein, a ratiometric fluorescent DNA nanostructure (RFDN) was designed for mitochondrial adenosine triphosphate (ATP) imaging in living cells. The DNA nanostructure was constructed by continuous hybridization of two hairpin DNA strands (HS1-Cy3 and HS2-Cy5) under the initiation of the trigger. HS1-Cy3 and HS2-Cy5 contained split aptamer fragments of ATP and are labeled with a fluorescent donor (Cy3) and acceptor (Cy5), respectively. The RFDN integrated multiple split aptamer fragments and increased the local concentration of sensing probes. The binding of ATP to aptamer fragments on the RFDN shortened the distance between Cy3 and Cy5, resulting in obvious ratiometric signals (fluorescence resonance energy transfer). The RFDN showed good biocompatibility and can be internalized into cells in a caveolin-dependent endocytosis pathway. The co-localization imaging results indicated that the DNA nanostructure could target the mitochondria via Cy3 and Cy5. Moreover, the confocal imaging results showed that the intracellular ATP changes stimulated by drugs in living cells could be indicated by the RFDN. In this way, the RFDN is expected to be a simple, flexible, and general platform for chemo/biosensing in living cells.

Despite their high theoretical energy density, the application of lithium-sulfur batteries is seriously hindered by the polysulfide shuttle and sluggish kinetics, especially with high sulfur loading and under low electrolyte usage. Herein, to facilitate the conversion of lithium polysulfides, nickel-boron (Ni-B) alloy nanoparticles, dispersed uniformly on carbon nanotube microspheres (CNTMs), are used as sulfur hosts for lithium-sulfur batteries. It is demonstrated that Ni-B alloy nanoparticles can not only anchor polysulfides through Ni-S and B-S interactions but also exhibit high electrocatalytic capability toward the conversion of intermediate polysulfide species. In addition, the intertwined CNT microspheres provide an additional conductive scaffold in response to the fast electrochemical redox. The enhanced redox kinetics is beneficial to improve the specific capacity and cycling stability of the sulfur cathode, based on the fast conversion of lithium polysulfides and effective deposition of the final sulfide products. Conclusively, the S/Ni-B/CNTM composite delivers a high specific capacity (1112.7 mAh gs-1) along with good cycle performance under both high sulfur loading (8.3 mg cm-2) and a lean electrolyte (3 μL mgs-1). Consequently, this study opens up a path to design new sulfur hosts toward lithium-sulfur batteries.

The development of efficient and stable electrocatalysts with earth-abundant elements for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in the same electrolyte is incontrovertibly vital in water electrolysis. However, their large-scale fabrication remains a great challenge. Here, we report a self-supported electrocatalyst in the form of Fe-doped Ni3S2 nanoparticles in-situ grown on three-dimensional (3D) conductive Fe−Ni alloy foam (Fe−Ni3S2/AF) by surface-assisted chemical vapor transport (SACVT) method. Homogeneous growth environment and scalability of SACVT method allow Fe−Ni3S2 nanoparticles uniformly growing on AF in large-scale. Fe−Ni3S2/AF exhibits high activity and durability when act as HER catalyst and OER precatalyst in alkaline media. The HER and OER overpotential at 10 mA/cm2 is considerably small, only 75 and 267 mV, respectively. Moreover, the electrolyzer assembled by Fe−Ni3S2/AF for overall water splitting exhibits a low cell voltage and high durability in long-term test. Based on experiments and theoretical calculation, the significantly enhanced activity could be originated from the incorporation of Fe, which contributed to increase the electrochemical active surface area, enhance electrical conductivity, optimize the hydrogen and H2O adsorption energy of Ni3S2 (101) surface in HER, and form active bimetallic Ni−Fe(oxy)hydroxide in OER. The excellent durability of self-supported Fe−Ni3S2/AF could be benefited from the in-situ growth of Fe−Ni3S2 nanoparticles on 3D AF, which could ensure closely mechanical adhesion between active materials and substrate, promote charge transport and increase surface area. This work provides a facile method for large-scale synthesis of electrocatalysts with high activity and long-term durability for efficient water electrolysis in alkaline media.

It is one of the future trends to create materials in situ by laser additive manufacturing. AlSi7Mg/nano-SiCp composites were successfully in situ prepared by selective laser melting in our previous study. After adding 2 wt% nano-SiC particles, the tensile stress and strain increased to 502.94 ± 6.40 MPa and 10.64 ± 1.06%, respectively. For the first time in the present study, we systematically studied and compared the wear performance and corrosion behavior of AlSi7Mg with its composite. We conducted the ball-on-flat frictional wear test at room temperature, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and the immersion corrosion tests in 3.5 wt% NaCl solution. The results showed that composite had higher wear resistance, while AlSi7Mg was more resistant to pitting corrosion. However, the further pitting corrosion of composite was restrained because of the in situ phase nano-Al4C3 and the residual nano-SiCp.

Proton exchange membrane fuel cell (PEMFC) has important implications for the success of clean transportation in the future. One of the key factors affecting the cost and performance of PEMFC is the cathode electrocatalyst for the oxygen reduction reaction (ORR) to overcome sluggish kinetics and instability in an acidic environment. As an essential component of the electrocatalyst, the support material largely determines the activity, mass transfer, charge transfer, and durability of the electrocatalyst. Thereby, the support material plays a critical role in the overall performance of the electrocatalyst. Carbon-based materials are widely used as electrocatalyst supports because of their high porosity, conductivity, chemical stability, and tunable morphology. Recently, some new carbon-based materials with excellent structure have been introduced, such as carbon nanotubes, carbon nanowires, graphene, metal–organic framework (MOF)-derived carbon, and biomass-derived carbon materials. Combined with a variety of strategies, such as controllable construction of porous structures and surface defects, proper doping heteroatoms, the ingenious design of model electrocatalysts, and predictive theoretical calculation, a new reliable path was provided for further improving the performance of electrocatalysts and exploring the catalytic mechanism. Based on the topic of carbon-based materials for ORR in acidic medium, this review summarizes the up-to-date progress and breakthroughs, highlights the factors affecting the catalytic activity and stability of ORR electrocatalysts in acids, and discusses their future application and development.

Deep learning-based semantic segmentation methods, such as fully convolutional networks (FCNs), are state-of-the-art techniques for object extraction from high spatial resolution images. However, c...

A new porous metal–organic framework (MOF) {[Cd(Hbptc)]·H2O}n (Cdbptc) was assembled by Cd(II) ions and a rigid (1,1′-biphenyl)-2,4,6-tricarboxylic acid (H3bptc) ligand via a solvothermal method. C...

Textile effluents containing synthetic refractory azo dyes are one of the most important sources of water pollution. However, these kinds of refractory organic pollutants did not resist a persulfate (PS) oxidation process which was correctly activated. In this study, PS was activated by ferrous sulfide (FeS) in a heterogeneous system to break down azo dyes wastewater. The results showed that all five selected azo dyes were efficiently broken down using the PS/FeS system, except for DY 12, and more than 95% of azo dyes were decolored within 60 minutes. The decolorization efficiency of DR 81 in the PS/FeS system was comparable to PS activated with heat (60 °C) or Fe2+, and was slightly superior to Fe0 powders under the same conditions. Quenching studies indicated that both SO4−• and •OH were formed in the FeS surface and diffused into the solution to facilitate the successive transformation of DR 81, the •OH reaction with DR 81 might the crucial reaction. The coexisting chelating agents in real azo dye effluents at high concentrations had a negative influence on azo dye decolorization by PS/FeS. However, the superior factor of the PS/FeS system was the regenerability and reusability of the heterogeneous catalyst. HIGHLIGHTS Five selected azo dyes were efficiently broken down using the PS/FeS system.; DR 81 decolorization by PS activated with FeS was comparable to other activators.; •OH might play a crucial role on DR 81 decolorization by PS/FeS system.; DR 81 decolorization proceeded by PS/FeS with correct coexisting chelating agents.; FeS was regenerable and recyclable in the heterogeneous PS/FeS system.

Polymer electrolyte membrane fuel cells (PEMFC) show substantial promise for their application in electric vehicles. For large-scale manufacturing of PEMFCs, roll-to-roll coated gas-diffusion-electrodes (GDE) offer certain advantages over other production pathways. Procedures including hot pressing and coating an ionomer overlayer may be necessary for this manufacturing pathway to enable a suitable catalyst layer/membrane interface. The same procedures may potentially introduce membrane irregularities, especially when thin membranes are used. Limited understanding exists regarding if and to what extent such irregularities impact PEMFC performance and lifetime, and therefore be considered defects. In this study, NREL's customized fuel cell hardware that enables quasi in-situ infrared (IR) thermography studies was utilized to visualize spatial hydrogen crossover and identify membrane irregularities that originated from the GDE-based MEA fabrication process. The structure of these membrane irregularities was investigated by scanning electron microscopy (SEM) and its impact on initial H2/air performance was determined. Accelerated stress testing (AST) revealed that these irregularities develop into failure point locations. These results were validated across many MEAs with identified process-induced membrane irregularities. By selecting specific gas diffusion media properties and by fine tuning the MEA hot pressing parameters, the formation of such membrane irregularities was mitigated.

Multifunctional nanocarriers with a simple structure and biocompatibility for bioimaging, potential tumor targeting, and precise antitumor ability are promising in cancer therapy. Bioactive glass is an important biomaterial and has been used in clinical bone tissue repair due to the high biocompatibility and bioactivity. Herein, we report fetal bovine serum (FBS)-decorated europium-doped bioactive glass nanoparticles (EuBGN@FBS) with excellent biosafety and enhanced tumor targeting for cancer imaging and therapy. EuBGN@FBS showed the controlled photoluminescent properties and pH-responsive anticancer drug release behavior. The FBS decoration significantly enhanced the dispersibility in physiological medium and improved hemocompatibility and cellular uptake of EuBGN. Relative to EuBGN, EuBGN@FBS could also efficiently image the cancer cell and show significantly enhanced targeted tumor imaging and chemotherapy in vivo while retaining negligible side effects. The simple and biocompatible structure with efficient tumor targeting, imaging, and therapy makes EuBGN@FBS highly promising in future cancer therapy.

Two ionic liquid (IL) thermomorphic systems were designed. The thermoregulated property exhibited by the IL systems was utilized for the recovery of Au(III) from acidic medium. The cloud point order of the two ILs was proposed and evidenced via a combination of experimental measurements and quantum chemical calculations. The impacts of salt ions and acid on the thermomorphic phase behavior of the IL–H₂O binary mixture system were investigated. After comprehensive comparison, a systematic study of Au(III) extraction by the [Suc][Tf₂N]₂ (succinyl bis(trifluoromethylsulfonyl)imide) system was carried out because of its outstanding hydrophobicity and extraction ability. Then, a comparison between traditional liquid–liquid extraction (TLLE) and homogeneous liquid–liquid extraction (HLLE) was made during the process of optimization of various extraction parameters. In addition, the anion-exchange mechanism in the extraction process was revealed. The thermoregulated [Suc][Tf₂N]₂ system presented an excellent selectivity for Au(III) in a solution of coexisting multimetallic ions. Finally, Au(III) was almost completely stripped from the loaded IL phase by oxalic acid. The extraction efficiency of Au(III) using regenerated IL still maintains a surprising stability after five turns of cycling experiments. Hence, the dicationic IL [Suc][Tf₂N]₂ was regarded as a potential extractant for the recovery of gold.

As a pivotal technique of data mining and data analysis, machine learning (ML) is gradually revolutionizing how materials are discovered with the rise of big data. Catalysis informatics are rising ...

A Pd-catalyzed hydrothiocarbonylation of unactivated terminal alkenes is presented. According to this protocol, aliphatic thioesters were synthesized with exclusive linear selectivity under mild reaction conditions. Good to excellent yields (up to 91% yield), broad substrate scope, broad functional group tolerance, and utility of the method demonstrated the advantages of this protocol.

Tensile properties at room temperature of a new casting Ni-base superalloy during aging at 800 °C for 0-1000 h were investigated. During aging, granular M23C6 carbides presented at grain boundaries and kept growing from dispersed particles to continuous networks. The γ′ phase significantly coarsened, with the morphology of some γ′ phase changed from spherical to rounded cubic shape after 1000 h. Three deformation mechanisms in relation to the γ′ diameter (dγ′) were identified: (i) weakly coupled dislocations (WCD) connected by anti-phase boundary (APB) traveled in pair across the γ/γ′ structure when dγ′ was small in the under-aged alloys; (ii) strongly coupled dislocations (SCD) with reduced spacing compared to (i) sheared γ′ phase when dγ′ increased in the over-aged alloys; (iii) dislocations occasionally by-passed γ′ phase when dγ′ was larger than 97 nm after aging for more than 300 h. The alloy obtained the peak strength when 20 h-aged with dγ′ = 44 nm which was in the transition between (i) and (ii). The aging-induced variation in yield strength was correlated to the coarsening of γʹ phase using a theoretical model of precipitation strengthening in terms of the formation of APB. The calculated results suggested that the γ′ phase with a volume fraction of 23% contributed more than 61% of the peak-aged yield strength. Observation after fracture revealed that the alloys usually fractured at grain boundaries. High stress concentration around carbides resulted in cracks by carbides self-cracking and the initiation of cavities. The undesirable agglomeration of M23C6 at grain boundaries was harmful to the properties of the over-aged alloys.

Type II diabetes mellitus (T2DM) is a metabolic disease with high incidence, which has seriously affected human life and health. The associations among waist circumference (WC), waist-to-hip ratio (WHR), and T2DM were discovered in observational studies. However, the causality of these associations still remains unknown. The present study aims to apply two-sample Mendelian randomization (TSMR) using genetic variants as instrumental variables (IVs) to evaluate the causality among WC, WHR, and T2DM. The participants were from three independent studies in genome-wide association studies (GWAS) datasets, which included 127,997 Europeans for WC, 73,137 Europeans for WHR and 659,316 Europeans for T2DM. Furthermore, 16 were associated WC SNPs and eight were associated WHR SNPs as instrument variables were selected for TSMR using P

Titanium dioxide (TiO2) nanoparticles (NPs) are employed as an ultraviolet filter in sunscreen products because of their high ultraviolet absorptivity. However, sunscreen sprays may pose health risks due to the toxicity of inhaled TiO2 NPs. Therefore, we estimated the potential human health risk posed by inhaled TiO2 NPs emitted from sunscreen sprays. The physiology-based lung model was employed to predict the lung TiO2 NPs burden caused by long-term exposure. A Hill-based dose–response model described the relationship between lung inflammation and TiO2 NP accumulation. The Weibull threshold model was used to estimate the threshold amount of accumulation inducing 0.5% of the maximum increase in neutrophils. The potential health risk was assessed using a hazard quotient–based probabilistic risk model. All data obtained to date indicate that application of sunscreen sprays poses no significant health risk. However, using data simulations based on the threshold criterion, we discovered that in terms of practical strategies for preventing the risks posed by inhaled TiO2 NPs emitted from spray products, the suggested daily use amount and pressing number are 40 g (95% confidence interval: 11–146 g) and 66 (18–245), respectively. In this study, we successfully translated the potential health risk of long-term exposure to NP-containing sunscreen sprays and recommendations for daily application into mechanistic insights.

The demand for transportation diesel fuels has been increasing in most countries for the last decade. As is one of the primary sources for diesel distillates, light cycle oil (LCO), having the advantages of inheriting similar density and boiling point range to diesel fuels, but high contents of aromatics, sulfur, and nitrogen, needs to be upgraded before being utilized. This work reports a trinary porous SiO2–Al2O3–TiO2 (SAT) synthesized by sol–gel method and used as the NiMo catalyst support for the LCO hydro-upgrading. NiMo/Al2O3-zeolite (AZ) was used as a reference to evaluate the performances of the NiMo/SAT. The catalysts were characterized by XRD, BET, Pyridine-FTIR, and TEM; and evaluated in a 20-mL fixed-bed microreactor using a Fluid Catalytic Cracking LCO as feedstock. It was found that the SAT support possessed a high surface area, high pore volume, and good acid properties. The NiMo/SAT catalyst exhibited even better hydrodesulfurization, hydrodenitrogenation, and hydrodearomatization performances than NiMo/AZ when the reaction was performed at 375 °C and 1100 psi. Compared with the zeolite addition catalyst, the SAT catalyst has the advantages of simple synthesis procedures and low input cost.

Nitric oxide (NO) is a gaseous signal molecule with multiple physiological functions, and it also plays a key role in cancer therapy. However, the production of NO which depends on O2 or H2 O2 is limited within the tumor microenvironment, leading to unsatisfactory anticancer effect. Herein, we report a NO-based phototherapeutic strategy mediated by photogenerated holes for hypoxic tumors, which is achieved by irradiation of the poly-L-arginine modified carbon-dots-doped graphitic carbon nitride nanomaterial (ArgCCN). Upon red light irradiation, the photogenerated holes on ArgCCN oxidized water into H2 O2 which subsequently oxidized the arginine residues to produce NO. In vitro and in vivo experiments showed that the high concentration of NO produced by ArgCCN could induce cancer cell apoptosis. The presented phototherapeutic strategy is based on microenvironment-independent photogenerated holes mediated oxidation reaction, paving the way for the development of NO therapeutic strategy.

In fault-bounded lacustrine basins, the lake basement may be exposed due to tilting of crustal blocks, forming islands of varying size. Such islands are commonly associated with sandy facies that may serve as important reservoirs for oil and gas accumulation. The present study investigated large sand bodies of Pleistocene-Holocene age on Songmenshan Island in the center of Poyang Lake, Jiangxi Province, southern China. The relationship of sedimentation on Songmenshan Island to its formation history was analyzed by means of Google satellite observations and field studies combined with scanning electron microscope, grain size, and 14 C dating analyses. The area of Songmenshan Island (39 km2) represents 8% of the total lake area (500 km2), and its height (81 m) is several times greater than that of the depth of the surrounding lake (13 m). The island has been uplifted since ~ 5 Ma at a rate of ~ 16 m Myr− 1 as a consequence of intrabasinal block faulting. The surficial deposits of the island consist of wave-controlled beach-bars in the lower part (

Nitrate ([Formula: see text]) and ammonium ([Formula: see text]) are major inorganic nitrogen (N) supplies for plants, but [Formula: see text] as the sole or dominant N source causes growth inhibition in many plants, known as ammonium toxicity. Small amounts of [Formula: see text] can significantly mitigate ammonium toxicity, and the anion channel SLAC1 homolog 3 (SLAH3) is involved in this process, but the mechanistic detail of how SLAH3 regulates nitrate-dependent alleviation of ammonium toxicity is still largely unknown. In this study, we identified SnRK1.1, a central regulator involved in energy homeostasis, and various stress responses, as a SLAH3 interactor in Arabidopsis (Arabidopsis thaliana). Our results suggest that SNF1-related protein kinase 1 (SnRK1.1) functions as a negative regulator of SLAH3. Kinase assays indicate SnRK1.1 strongly phosphorylates the C-terminal of SLAH3 at the site S601. Under high- [Formula: see text] /low-pH condition, phospho-mimetic and phospho-dead mutations in SLAH3 S601 result in barely rescued phenotypes and fully complemented phenotypes in slah3. Furthermore, SnRK1.1 migrates from cytoplasm to nucleus under high- [Formula: see text] /low-pH conditions. The translocation of SnRK1.1 from cytosol to nucleus under high-ammonium stress releases the inhibition on SLAH3, which allows SLAH3-mediated [Formula: see text] efflux leading to alleviation of high- [Formula: see text] /low-pH stress. Our study reveals that the C-terminal phosphorylation also plays important role in SLAH3 regulation and provides additional insights into nitrate-dependent alleviation of ammonium toxicity in plants.

We employ ZnSe films and graphene to act as light-absorbing layer and channel, respectively. Low-flexibility yet high-absorbance ZnSe light-absorbing layer makes contribution to the absorbance and have no negative impact on the device flexibility, while high-flexibility graphene films determine the flexibility. As a result, the image sensors based on 4-inch flexible ZnSe/graphene hybrids with a high responsivity of $1.5\times 10^{{6}}$ A/W could work stably under the large strain up to 0.2%. This is one order of magnitude larger than that of pure ZnSe films-based devices. More importantly, they make a stable performance under the strain of 0.2% after 10,000 bending cycles or a bending duration of 1000 h.

The discrete element method (DEM) is commonly used for simulating the mechanical characteristics of rock materials; however, constructing a DEM model requires the specification of a number of microparameters. In this paper, to obtain the microparameters of the DEM model, the improved particle swarm optimization (PSO) calibration method was presented. Based on numerical simulation examples, the new approach is considered valid for calibrating the microparameters of the DEM model. Moreover, it is concluded that different sets of microparameters can be determined when few macroparameters are used, which indicates that the empirical formula between microparameters and macroparameters is not reliable. From the analysis of the numerical simulation results, it is suggested that more macroparameters should be used to calibrate the microparameters of the DEM model, and the corresponding numerical simulation results could be more reliable; otherwise, the generated numerical model may not accurately simulate the mechanical characteristics of rock materials.

Surface magnetic configurations and electromagnetic responding behaviors can be efficiently modulated by controlling the growth of magnetic materials, which has always been a huge challenge. Here, an in situ orientation growth strategy is developed to build a micron scale Fe3O4–Fe3O4@C heterojunction via applying Kirkendall diffusion to the orientation growth process. Undergoing precipitation and phase transition process, the oriented Fe3O4 octahedron tightly rooted in anisotropy Fe3O4@C body, constructing various magnetic configurations and enhancing stray magnetic field intensity. As-synthesized magnetic-dielectric microspheres exhibited excellent energy conversion capacity toward electromagnetic wave, including strong reflection loss (RL: 40.8 dB, 2.0 mm) and ultra-wide absorption region (∼11.04 GHz, ∼69% of the tested frequency). Essentially, cross-space magnetic coupling enlarges the responding region beyond the material itself and strengthens electromagnetic wave disputation. Local charge density distribution around the grain boundary plays the key role in forming the enhanced interfacial polarization, which is characterized by the off-axis electronic holography. More importantly, the dynamic response mechanism was firstly observed under an applied magnetic field. Changing magnetic configurations induce the rearrangement of magnetic flux distribution, providing the internal magnetic feedback. Above-mentioned dielectric and magnetic properties of Fe3O4–Fe3O4@C composites make a breakthrough understanding toward the energy conversion mechanisms.

Heterosis has been extensively utilized to increase productivity in crops, yet the underlying molecular mechanisms remain largely elusive. Here, we generated transcriptome-wide profiles of mRNA abundance, m6A methylation, and translational efficiency from the maize F1 hybrid B73×Mo17 and its two parental lines to ascertain the contribution of each regulatory layer to heterosis at the seedling stage. We documented that although the global abundance and distribution of m6A remained unchanged, a greater number of genes had gained an m6A modification in the hybrid. Superior variations were observed at the m6A modification and translational efficiency levels when compared with mRNA abundance between the hybrid and parents. In the hybrid, the vast majority of genes with m6A modification exhibited a non-additive expression pattern, the percentage of which was much higher than that at levels of mRNA abundance and translational efficiency. Non-additive genes involved in different biological processes were hierarchically coordinated by discrete combinations of three regulatory layers. These findings suggest that transcriptional and post-transcriptional regulation of gene expression make distinct contributions to heterosis in hybrid maize. Overall, this integrated multi-omics analysis provides a valuable portfolio for interpreting transcriptional and post-transcriptional regulation of gene expression in hybrid maize, and paves the way for exploring molecular mechanisms underlying hybrid vigor., A maize F1 hybrid and its parental lines showed dissimilarities of regulatory and heterotic patterns of genes undergoing hierarchical regulation at the mRNA abundance, m6A modification, and translational efficiency.

Metal-organic framework (MOF) derivatives have been arousing great attention in microwave absorption (MA) applications because of the adaptable morphological and component variance. However, it is still a huge challenge to construct multi-dimensional assembly with special heterostructure based on MOF and conductive carbon materials for excellent MA performance. Here, we successfully synthesized the cube-like assembly of multi-walled carbon nanotubes (MWCNTs) and ZnO (ZnO@MWCNTs) with unique multi-dimensional architecture via controlling the pyrolysis time of MOF-5 wrapped by MWCNTs. The ZnO@MWCNTs-4h are composed of zero-dimensional ZnO nanoparticles, one-dimensional MWCNTs, and three-dimensional micro-scale porous carbon framework. These various dimensional components confined within the cube space lead to the strong reflection loss (RL) at different frequencies, thus resulting in exceptional MA performance. The ZnO@MWCNTs-4h can reach a RL peak of −34.4 dB at only 1.5 mm thickness. More importantly, the maximum RL can achieve −47.4 dB at 2.7 mm with a mass loading as low as 20%. The optimized MA performance can be ascribed to high-density polarized sites, tightly interwoven MWCNTs conductive network, and strong multiple scattering that all induced by the multi-dimensional structures and components. Therefore, novel ZnO@MWCNTs composites are promising as a lightweight and highly efficient microwave absorber.