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BACKGROUND A typical irrigation area of the downstream Yellow River (Henan) is an important agricultural planting area in the northern Henan Plain. The shallow water quality in this area is generally poor, which is often used for crop irrigation or livestock drinking, posing a risk to human health. Therefore, the study on the variation characteristics and mechanism of arsenic and fluorine content in groundwater in this area will help to improve the level of understanding of pollution in this area. OBJECTIVES To investigate the spatial variation characteristics and mechanism of arsenic and fluorine concentration. METHODS Based on 327 groups of shallow groundwater samples collected in 2010 and 2020 in the irrigated area, the distribution of arsenic and fluorine in the groundwater of the irrigated area was analyzed, and compared to the evolution characteristics of arsenic and fluorine in the shallow groundwater of the irrigated area in the last ten years. RESULTS In 2020, the number of samples with high arsenic concentration (>10μg/L) and high fluorine concentration (>1mg/L) in shallow groundwater accounted for 26.1% and 26.06%, respectively. The high-arsenic groundwater was distributed in the sedimentary environments with interbedding structure of sediment, such as the Taihang Mountain depression and the Yellow River alluvial plain, with strong reducibility, poor groundwater runoff and strong cation exchange, resulting in high concentration of Ca2+ in the environment. Arsenic concentration increased in 31.8% of water samples and decreased in 36.7% of water samples in the last ten years. The increase of arsenic content was caused by the dissolution and release of manganese oxide due to the enhanced reducibility of groundwater. The variation of water level caused by agricultural irrigation and water replacement in different areas during the last ten years was a potential factor of arsenic concentration change. The high-fluorine groundwater was mainly distributed along the Yellow River in Xinxiang and Puyang, Henan Province. The concentration of fluorine ion was affected by the dissolution of calcareous minerals such as fluorite in the sediments, which made the high-fluorine groundwater appear in the low-calcium environment. In the last ten years, the study area with decreased fluorine ion concentration accounted for 60.2%, whereas areas with increased fluorine ion concentration accounted for 32.1%. The overall change trend was good, but the fluorine ion concentration in the high fluorine area continued to increase. Changes in fluorine concentration were also affected by changes in Ca2+, with further increases (decreases) as Ca2+ concentration decreased (increased). Elevated fluorine in groundwater was distributed along the Yellow River, affected greatly by the Yellow River water supply. So, the groundwater flow condition was good and the cation exchange was weakened, reducing the Ca2+ content. At this time, the arsenic content in the groundwater was less affected by the environment, so the study area with fluorine increase showed an inverse relationship between arsenic and fluorine in terms of regional distribution and evolution. CONCLUSIONS This study will provide support for rational utilization of groundwater in the study area.

Empirical therapies using polymyxins combined with other antibiotics are recommended in the treatment of Acinetobacter baumannii infections. In the present study, the synergistic activities of polymyxin-B, meropenem, and sulbactam as combination therapy were investigated using metabolomic analysis. The metabolome of A. baumannii was investigated after treatment with polymyxin-B alone (2 mg/l), meropenem (2 mg/l) alone, combination of polymyxin-B/meropenem at their clinical breakpoints, and triple-antibiotic combination of polymyxin-B/meropenem and 4 mg/l sulbactam. The triple-antibiotic combination significantly changed the metabolite levels involved in cell outer membrane and cell wall biosynthesis, including fatty acid, glycerophospholipid, lipopolysaccharide, peptidoglycan, and nucleotide within 15 min of administration. In contrast, significant changes in metabolome were observed after 1 h in sample treated with either meropenem or polymyxin-B alone. After 1 h of administration, the double and triple combination therapies significantly disrupted nucleotide and amino acid biosynthesis pathways as well as the central carbon metabolism, including pentose phosphate and glycolysis/gluconeogenesis pathways, and tricarboxylic acid cycle. The addition of sulbactam to polymyxin-B and meropenem combination appeared to be an early disruptor of A. baumannii metabolome, which paves the way for further antibiotic penetration into bacteria cells. Combination antibiotics consisting of sulbactam/meropenem/polymyxin-B can effectively confer susceptibility to A. baumannii harboring OXA-23 and other drug resistant genes. Metabolomic profiling reveals underlying mechanisms of synergistic effects of polymyxin-B combined with meropenem and sulbactam against multi-drug resistant A. baumannii.

As a metal of strategic value, tungsten plays an important part in civil and military applications. Currently, China is the biggest tungsten producer all over the world, and the metallic smelting technologies for tungsten are well established. However, the harmless recovery and treatment procedures for tungsten residue remain rather underdeveloped. The treatment of tungsten residue generally includes the recovery of valuable metals (e.g., scandium, tantalum, and niobium) and the solidification of toxic elements (e.g., arsenic, lead, and chromium), which may control the transfer of these elements and metals. If treated improperly, the resource of tungsten residue may be wasted, and potential environmental risks could arise. Therefore, the safe disposition of tungsten residue has become the limit factor and an urgent problem to be solved for the sustainable development of tungsten-related industries. In this regard, we reviewed the industrial background of tungsten and the composition and toxicity characteristics of tungsten residue. In addition, particular attention was paid to the harmless utilization processes and technologies for tungsten residue, which were then systematically compared in terms of the applicable situations as well as their advantages and shortcomings. Finally, the development trend for the harmless utilization of tungsten residue was discussed, and some proposals for further studies were provided.

A convolutive blind source separation algorithm was proposed based on tensor decomposition framework, to address the estimation of mixed filter matrix and the permutation alignment of frequency bin simultaneously.Firstly, the tensor models at all frequency bins were constructed according to the estimated autocorrelation matrix of the observed signals.Secondly, the factor matrix corresponding to each frequency bin was calculated by tensor decomposition technique as the estimated mixed filter matrix for that bin.Finally, a global optimal permutation strategy with power ratio as the permutation alignment measure was adopted to eliminate the permutation ambiguity in all the frequency bins.Experimental results demonstrate that the proposed method achieves better separation performance than other existing algorithms when dealing with convolutive mixed speech under different simulation conditions.

To recognize the modulation style adopted in multiple-input-multiple-output orthogonal space-time block code (MIMO-OSTBC) systems, a cooperative modulation recognition algorithm based on the one-dimensional convolutional neural network (1D-CNN) was proposed.With the lossless I/Q signal selected as shallow features, the zero-forcing blind equalization was first leveraged to improve the discrimination of different modulation signals.Then the 1D-CNN recognition model was devised and trained to extract deep features from shallow ones.Later, two decision fusion strategies of voting-based and confidence-based were leveraged in the multiple-antenna receiver to improve recognition accuracy.Experimental results show that the proposed algorithm can effectively recognize five modulation types {BPSK, 4PSK,8PSK,16QAM,4PAM}, with a 100% recognition accuracy when the signal-to-noise is equal or greater than-2 dB.

In this study, the phase composition, morphology, and element distribution of Mg impurities in a low-grade titanium slag and in its chlorinated residue after carbochlorination were identified using XRD, SEM-EDS, and MLA. Most Mg impurities existed as anosovite, rutile, titanaugite, and Ti silicate phases before the carbochlorination process. The thermodynamic analysis revealed that the chlorination tendencies of Mg, Ti, Ca, Fe, and Mn oxides in the original titanium slag was much higher than those of Si and Al oxides in the temperature range of 700–850 °C. In addition, the binary phase diagram analysis indicates that the magnesium chloride (MgCl2) byproduct formed Na2MgCl4 eutectic salts in the NaCl-based salt bath. The carbochlorination experiments of the Mg-bearing titanium slag show that the chlorination ratio of magnesium oxide was above 93% under the suitable industrial conditions used for the extraction of titanium from Mg-bearing titanium slag. In addition, the formation of Na2MgCl4 eutectic salts after carbochlorination was confirmed, indicating that the negative effect of MgCl2 on the chlorination process was effectively eliminated. The Mg impurities in the chlorinated residue existed as titanaugite, quartz, chlorite, and rutile phases. Furthermore, we found that the carbochlorination of Mg-bearing titanium slag in chloride media effectively improved the comprehensive utilization efficiency of the Mg-bearing titanium slag. We believe that the proposed carbochlorination mechanism of the Mg-bearing titanium slag will provide thorough understanding and useful guidance on the practical industrial application of Mg-bearing titanium slag.

Endogenous Plastic Somatic (ePS) cells isolated from adult human tissues exhibit extensive lineage plasticity in vitro and in vivo. Here we visualize these rare ePS cells in a latent state, i.e. lacking SOX2, OCT3/4 and NANOG (SON) expression, in non-diseased breast specimens through immunohistochemical analysis of previously identified ePS-specific biomarkers (CD73+, EpCAM+ and CD90-). We also report a novel mechanism by which these latent ePS cells acquire SON expression and plasticity in vitro. Four extracellular factors are necessary for the acquisition of SON expression and lineage plasticity in ePS cells: adenosine (which is produced by the 5' ecto-nucleotidase CD73 and activates in turn the PKA-dependent IL6/STAT3 pathway through the adenosine receptor ADORA2b), IL6, FGF2 and ACTIVIN A. Blocking any pathway component renders ePS cells incapable of SON expression and lineage plasticity. Notably, hESCs do not use adenosine or IL6 nor they express CD73 or ADORA2b and inhibition of adenosine signaling does not ablate their plasticity. Therefore, the data presented here delineate novel circuitry and physiological signals for accessing SON expression in rare, undifferentiated human cells.

The larvae of Clanis bilineata tsingtauica, a special species of Chinese edible insect, are of great nutritional, medicinal and economic value to humans. This study aimed to clarify the effect of different soybean varieties (Guandou-3 (G3), Ruidou-1 (R1), September cold (SC)) on the nutritional quality and feeding selection behavior of C. bilineata tsingtauica larvae. The results showed that soybean isoleucine (Ile) and phenylalanine (Phe) were positively correlated with larval host selection (HS) and protein content. The order of soybean plants selected by C. bilineata tsingtauica larvae was R1 > SC > G3, and they selected R1 significantly higher than SC and G3 by 50.55% and 109.01%, respectively. The protein content of the larvae fed on R1 was also the highest among the three cultivars. In addition, a total of 17 volatiles belonging to 5 classes were detected from soybeans: aldehydes, esters, alcohols, ketones, and heterocyclic compounds. Pearson’s analysis showed that soybean methyl salicylate was positively correlated with larval HS and their protein content, and soybean 3-octenol was negatively correlated with larval HS and their palmitic acid content. In conclusion, C. bilineata tsingtauica larvae are more adapted to R1 than to the other two soybean species. This study provides a theoretical basis for the production of more protein-rich C. bilineata tsingtauica in the food industry.

Almost five billion individuals worldwide use social networking sites (SNSs) such as Instagram, Facebook, Snapchat, and X (formerly known as Twitter). The social rewards obtained on these sites induce users to spend substantial durations of time on them. However, current research demonstrates mixed findings on whether greater time on SNSs is related to riskier decision-making and impulsive tendencies. To address these findings, we conducted an online study (n = 225) to assess how time across four SNSs relates to impulsive decision-making in the delay discounting task. We included each trial as an individual choice in a regression model predicting preference for the immediate reward, for a total of 20,265 choices. Greater average time across all SNSs was related with a higher likelihood of choosing the immediate, but smaller, reward. In other words, people who spent more time on SNSs also made more impulsive decisions. When including individual platforms, greater time on Instagram and X, but not Facebook or Snapchat, was related with a higher likelihood of choosing the immediate reward. These findings help clarify prior literature on the relationship between platform specific SNS use and impulsive decision-making. We discuss limitations, directions for future research, and broader implications for the field. [ABSTRACT FROM AUTHOR]

Insecticide resistance in Panonychus citri is a major obstacle to mite control in citrus orchards. Pyrethroid insecticides are continually used to control mites in China, although resistance to pyrethroids has evolved in some populations. Here, the resistance to the pyrethroid fenpropathrin was investigated and 7 out of 8 field‐collected populations of P. citri exhibited a high level of resistance, ranging from 171‐fold to 15 391‐fold higher than the susceptible (SS) comparison strain. Three voltage‐gated sodium channel (VGSC) mutations were identified in the tested populations: L1031V, F1747L, and F1751I. Amplicon sequencing was used to evaluate the frequency of these mutations in the 19 field populations. L1031V and F1751I were present in all populations at frequencies of 11.6%–82.1% and 0.5%–31.8%, respectively, whereas the F1747L mutation was only present in 12 populations from Chongqing, Sichuan, Guangxi, and Yunnan provinces. Introduction of these mutations singly or in combination into transgenic flies significantly increased their resistance to fenpropathrin and these flies also exhibited reduced mortality after exposure to the pyrethroids permethrin and β‐cypermethrin. Panonychus citri VGSC homology modeling and ligand docking indicate that F1747 and F1751 form direct binding contacts with pyrethroids, which are lost with mutation, whereas L1031 mutation may diminish pyrethroid effects through an allosteric mechanism. Overall, the results provide molecular markers for monitoring pest resistance to pyrethroids and offer new insights into the basis of pyrethroid actions on sodium channels. [ABSTRACT FROM AUTHOR]

Zeugodacus cucurbitae Coquillett (Diptera: Tephritidae) is an agriculturally and economically important pest worldwide that has developed resistance to β‐cypermethrin. Glutathione S‐transferases (GSTs) have been reported to be involved in the detoxification of insecticides in insects. We have found that both ZcGSTd6 and ZcGSTd10 were up‐regulated by β‐cypermethrin induction in our previous study, so we aimed to explore their potential relationship with β‐cypermethrin tolerance in this study. The heterologous expression of ZcGSTd6 and ZcGSTd10 in Escherichia coli showed significantly high activities against 1‐chloro‐2,4‐dinitrobenzene (CDNB). The kinetic parameters of ZcGSTd6 and ZcGSTd10 were determined by Lineweaver–Burk. The Vmax and Km of ZcGSTd6 were 0.50 μmol/min·mg and 0.3 mM, respectively. The Vmax and Km of ZcGSTd10 were 1.82 μmol/min·mg and 0.53 mM. The 3D modelling and molecular docking results revealed that β‐cypermethrin exhibited a stronger bounding to the active site SER‐9 of ZcGSTd10. The sensitivity to β‐cypermethrin was significantly increased by 18.73% and 27.21%, respectively, after the knockdown of ZcGSTd6 and ZcGSTd10 by using RNA interference. In addition, the inhibition of CDNB at 50% (IC50) and the inhibition constants (Ki) of β‐cypermethrin against ZcGSTd10 were determined as 0.41 and 0.33 mM, respectively. The Ki and IC50 of β‐cypermethrin against ZcSGTd6 were not analysed. These results suggested that ZcGSTd10 could be an essential regulator involved in the tolerance of Z. cucurbitae to β‐cypermethrin. [ABSTRACT FROM AUTHOR]

Multi-element alloys (e.g., non-equiatomic FeMnCoCr alloys) have attracted extensive attention from researchers due to the breaking of the strengthen-ductility tradeoff relationship. Plenty of work has been conducted to investigate the ingredient-dependent deformation mechanism in these alloys in experiments. However, the atomic simulations on such parameter-related mechanisms are greatly limited with the lack of the related interatomic potentials. In this work, two interatomic potentials are developed within the embedded atom method (EAM) framework for Fe80−xMnxCo10Cr10 high-entropy alloys. The tunability of the cohesive energy-related martensitic transformation (MT) mechanism was comprehensively investigated using molecular dynamics (MD) through a series of unilateral crack configurations with different twin boundary spacings (TBs). It is noted that the main deformation mechanism around the crack tip is transformed from a martensitic transformation to dislocation activities (dislocation or twin) with the variation of different cohesive energies between face-centered cubic (fcc) and hexagonal close-packed (hcp) phases. Additionally, the introduction of twin boundaries significantly enhances the strength and toughness of the alloys. The newly developed interatomic potentials are expected to provide theoretical support for the related simulations, focusing the martensitic transformation mechanism on high-entropy alloys. [ABSTRACT FROM AUTHOR]