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Biomineralization has become a research focus in wastewater treatment due to its much lower costs compared to traditional methods. However, the low sodium chloride (NaCl)-tolerance of bacteria limits applications to only water with low NaCl concentrations. Here, calcium ions in hypersaline wastewater (10% NaCl) were precipitated by free and immobilized Halovibrio mesolongii HMY2 bacteria and the differences between them were determined. The results show that calcium ions can be transformed into several types of calcium carbonate with a range of morphologies, abundant organic functional groups (C-H, C-O-C, C=O, etc), protein secondary structures (β-sheet, α-helix, 3

Our study investigates whether miR-265 regulates the differentiation of rat bone marrow mesenchymal stem cells (BMSCs) into alveolar type II epithelial cells (ATII) through TGF-β1 and promotes lung injury repair in rats with sepsis, thereby inhibiting sepsis progression. 25 patients with sepsis admitted to the Respiratory and Critical Care Medicine Department of the hospital and 17 normal controls were included. TGF-β1 level was measured by ELISA. miR-265 level was measured by qRT-PCR and AT II-related genes and proteins expression was analyzed by western blot and qRT-PCR. miR-265 expression was significantly higher in sepsis patients than normal group. Progenitor BMSCs were long and shuttle-shaped after 1 and 3 days of growth. Cultured MSCs had low expression of the negative antigen CD34 (4.32%) and high expression of the positive antigen CD44 (99.87%). TGF-β1 level was significantly increased with longer induction time, while miR-265 expression was significantly decreased in cell culture medium. miR-265 interference significantly decreased TGF-β1 expression. In conclusion, miR-265 inhibits BMSC differentiation to AT II via regulation of TGF-β1, thereby inhibiting sepsis progression.

The single Bi4-xEuxTi3O12 and Ni1-xCuxFe2O4 films were prepared via spin-coating method. The composite films of the Bi3.4Eu0.6Ti3O12/Ni0.7Cu0.3Fe2O4, annealed under N2, air and O2, were also prepared via the same method. Compared with the films of Bi4Ti3O12, the films of the Eu-doped Bi4Ti3O12 (Bi4-xEuxTi3O12) exhibit enhanced ferroelectricity. And when x is equal to 0.6, the films of Bi4-xEuxTi3O12 show optimal ferroelectricity. Compared with the undoped NiFe2O4 film, in the films of Ni1-xCuxFe2O4, the doping of Cu2+ enhances ferromagnetism. And when x is equal to 0.3, the Ni1-xCuxFe2O4 films exhibit optimal ferromagnetism. For the composite films of Bi3.4Eu0.6Ti3O12/Ni0.7Cu0.3Fe2O4, annealing atmosphere has a significant impact on the magnetoelectric properties. In comparison with the composite films annealed under N2 and air, the composite films annealed under O2 exhibit optimum ferroelectricity (saturation polarization being 26.3 μC·cm−2), ferromagnetism (saturation magnetization being 385.6 emu·cm−3) and enhanced magnetoelectric coupling effect (magnetoelectric voltage coefficient being 86.4 mV·(cm·Oe)−1). This is beneficial for the applications in magnetoelectric functional devices.

Members of the genus Bacillus are known to play an important role in promoting plant growth and protecting plants against phytopathogenic microorganisms. In this study, 21 isolates of Bacillus spp. were obtained from the root micro-ecosystem of Suaeda glauca. Analysis of the 16S rRNA genes indicated that the isolates belong to the species Bacillus amyloliquefaciens, Bacillus velezensis, Bacillus subtilis, Bacillus pumilus, Bacillus aryabhattai and Brevibacterium frigoritolerans. One of the interesting findings of this study is that the four strains B1, B5, B16 and B21 are dominant in rhizosphere soil. Based on gyrA, gyrB, and rpoB gene analyses, B1, B5, and B21 were identified as B. amyloliquefaciens and B16 was identified as B. velezensis. Estimation of antifungal activity showed that the isolate B1 had a significant inhibitory effect on Fusarium verticillioides, B5 and B16 on Colletotrichum capsici (syd.) Butl, and B21 on Rhizoctonia cerealis van der Hoeven. The four strains grew well in medium with 1-10% NaCl, a pH value of 5-8, and promoted the growth of Arabidopsis thaliana. Our results indicate that these strains may be promising agents for the biocontrol and promotion of plant growth and further study of the relevant bacteria will provide a useful reference for the development of microbial resources.

Lead-free films of Bi4-xNdxTi3O12 were deposited on Pt(111)/Ti/SiO2/Si(100) substrate via spin-coating methods. It is shown that there are no secondary phases in Bi4-xNdxTi3O12 films and clear interfaces between the Bi4-xNdxTi3O12 films and substrates when the films are annealed at 700 ℃. And the Bi4-xNdxTi3O12 films also exhibit a blue light emission peak at 437 nm and a yellow light emission peak at 580 nm. There are narrower band gaps, higher dielectric constant and lower dielectric loss when Nd3+ concentration varies from 0 to 0.85. And the Bi3.15Nd0.85Ti3O12 film possesses the minimum of band gap energy (2.67 eV). Moreover, Bi3.55Nd0.45Ti3O12 film exhibits a minimal leakage current density and a maximal remanent polarization, which is highly beneficial for the potential applications in multi-functional devices.

Biotechnological hydrogen production is considered as an environmentally sustainable alternative to petrochemical sources or electrolysis. Here, disruption of lactate dehydrogenase (LDH) and metabolic regulation via the small RNA RyhB were adopted to improve hydrogen production in the novel Klebsiella sp. strain FSoil 024. The hydrogen production of FSoil 024-L (Δldh) and FSoil 024-L/R (Δldh/RyhB) from glucose in a 5-L fermenter respectively increased by 40 and 50% compared to the wild type. When glycerol was adopted as a more favorable substrate, FSoil 024-L generated 3.3 L/L of hydrogen after 52 h of fermentation, implying its great potential for the utilization of crude glycerol to produce hydrogen. Overexpression of RyhB downregulated formate biosynthesis in FSoil 024, thereby redirecting NADH toward the hydrogen production pathway. This finding provides new insights into the role of cellular reducing power in hydrogen metabolism and establishes a rationale for improving hydrogen production.

The films of (Bi0.5Na0.5)(Ti1-xMnx)O3-δ (BNTMx) were deposited on the substrates via the sol–gel method. The influence of the doping content of Mn on the microstructures and ferroelectric properties of the films were investigated. In addition, the valence states of Mn ions were analyzed. The results show that Mn ions have dissolved into the lattice of Bi0.5Na0.5TiO3 (BNT) without forming any secondary phase. When the doping content of Mn is 0.04, the film of BNTMx possesses a dense microstructure, maximum of remnant polarization (20.2 µC·cm−2), minimum value of leakage current density (3.31 × 10–5 A· cm−2), which shows good ferroelectric property and insulation performance. The results of XPS indicate that Mn ions exist in form of Mn2+, Mn3+ and Mn4+. The ratio of the amount of Mn4+ to that of Mn3+ and Mn2+ is 5.5:1. In this work, relationship between valence states of Mn ions and leakage current densities or ferroelectric property of the films were investigated in detail. The results will provide a new way for future applications of BNT-based multi-functional devices and an alternative for environmental-friendly ferroelectric materials.

The magnetoelectric composite films of Bi3.15Nd0.85Ti2.9Zr0.1O12 (BNTZO)–CoFe2O4 (CFO) were deposited on the substrates of Pt/Ti/SiO2/Si (111) by means of the sol–gel method. The results show that, in the composite films, there are tri-axial compressive stresses in the CFO films. Nevertheless, there are bi-axial tensile stresses and uniaxial compressive stress in the BNTZO films. The composite films possess compact microstructure and flat interface without forming intermediate layer. The composite films have good magnetoelectric properties besides both good ferroelectric and ferromagnetic properties. When Hdc is 738 Oe, the composite film of BNTZO-CFO possesses the maximum of αE, 114 mV cm−1 Oe−1, which is helpful for the application in multi-functional devices.

Lung natural killer (NK) cells can be classified into tissue-resident NK (trNK) cells and conventional NK (cNK) cells. Both trNK and cNK are composed of multiple subsets with unique phenotypes and functional characteristics. However, the phenotypic and functional differences between the two captured less attention. The features of trNK and cNK in the development, phenotypes and functions are sorted, and the interactions between NK cells and other immune cells in the lung are presented. Moreover, the latest research progress of lung NK cells in lung infections, tumors, transplantation, asthma and other diseases is particularly highlighted. It suggests that trNK cells may play a significant role, although lung NK cells are mainly composed of cNK. Further investigations of lung trNK and cNK cells will provide new insights into NK cell-based disease research.

Cd exposure has been demonstrated to induce a variety of metabolic disorders accompanied with imbalance of glucose and lipid homeostasis. The metabolic toxicity of Cd exposure at metabolome-wide level remains elusive. In our study, we demonstrated that Cd exposure via drinking water increased blood glucose levels, decreased serum insulin levels, led to glucose intolerance and suppressed insulin expression in the pancreas of C57/6J mice. Cd exposure significantly inhibited cell viability and suppressed insulin secretion in MIN6 cells in vitro. Since pancreatic β-cells are the only source of insulin production in the body and play a pivotal role in modulating glucose and lipid metabolisms, we further delineated the metabolomic signatures of Cd exposure in insulin-secreting MIN6 cells by using non-target metabolomics. PCA and OPLS-DA analysis clearly suggested that Cd exposure led to a marked metabolic alteration in MIN6 cells. 76 perturbed metabolites were identified after Cd exposure. Classification of metabolites suggested that Cd perturbed metabolites belong to nucleosides, nucleotides and analogues, organic acids and derivatives, and lipids and lipid-like molecules. 28 perturbed metabolites existed in mitochondrion, suggesting mitochondrion as the major target organelle in metabolic toxicity of Cd exposure. KEGG pathway analysis revealed that 20 metabolic pathways were disturbed by Cd exposure. Mitochondrial TCA cycle and glycerophospholipid metabolism were remarkably disturbed. The mRNA expressions of genes in mitochondrial TCA cycle and fatty acid oxidation in pancreas and MIN6 cells were significantly dysregulated by Cd exposure. Disturbances in mitochondrial TCA cycle and glycerophospholipid metabolism result in producing perturbed metabolites in pancreatic β-cells. Moreover, 14 perturbed metabolites identified in MIN6 cells co-existed in the urine of Cd exposed workers. 11 biomarkers of diabetes mellitus were also found to be significantly altered in the urine of Cd exposed workers. In conclusion, findings of this study greatly extend our understanding of metabolic toxicity of Cd exposure in pancreatic β-cells at metabolome-wide level and offer some new clues for linking Cd exposure to development of diabetes mellitus. Results of this study also support the notion that Cd induced metabolic toxicity could be monitored by examining perturbed urinary metabolites in humans and highlight the significance of reducing Cd exposure via drinking water at population level.

Calcium ions in industrial wastewater needs to be removed to prevent the production of limescale, which can have negative consequences. Biomineralization has become the focus due to its lower costs than traditional methods of remediation. In this study, calcium ions were bio-precipitated under the action of free and immobilized Bacillus amyloliquefaciens DMS6 bacteria, and the calcium ion removal efficiency was also compared. The results show that it only needed 3 days to decrease the calcium ion concentration to an ideal level of 76-116 mg/L under the action of DMS6 bacteria immobilized by activated carbon fiber, with calcium ion removal ratios reaching 99%-95% by the 7

Biotechnological production of 2,3-butanediol (2,3-BD), a versatile platform bio-chemical and a potential biofuel, is limited due to by-product toxicity. In this study, we aimed to redirect the metabolic flux toward 2,3-BD in Enterobacter aerogenes (E. aerogenes) by increasing the intracellular NADH pool. Increasing the NADH/NAD+ ratio by knocking out the NADH dehydrogenase genes (nuoC/nuoD) enhanced 2,3-BD production by up to 67% compared with wild-type E. aerogenes. When lactate dehydrogenase (ldh) was knocked out, the yield of 2,3-BD was increased by 71.2% compared to the wild type. Metabolic flux analysis revealed that upregulated expression of the sRNA RyhB led to a noteworthy shift in metabolism. The 2,3-BD titer of the best mutant Ea-2 was almost seven times higher than that of the parent strain in a 5-L fermenter. In this study, an effective metabolic engineering strategy for improved 2,3-BD production was implemented by increasing the NADH/NAD+ ratio and blocking competing pathways.

In this study, the films of Bi4−xEuxTi3O12 (x = 0, 0.2, 0.4, 0.6, 0.8) were prepared on substrates (Pt(111)/Ti/SiO2/Si(100)) by the spin-coating method. The results indicate that the films of Bi4−xEuxTi3O12 annealed at 700 °C consist of Bi4Ti3O12 and Pt from the substrates. This indicates that Eu3+ has dissolved into the lattice of Bi4Ti3O12. The doping of Eu3+ to the films of Bi4Ti3O12 enhances ferroelectric properties as well as photoluminescent properties. The films of Bi4−xEuxTi3O12 show two orange emission perks at 590 nm and 595 nm, and a red emission at 613 nm. These three peaks are ascribed to 5D0 → 7F0, 5D0 → 7F1, and 5D0 → 7F2, respectively. The bandgaps of the films of Bi4−xEuxTi3O12 range from 3.07 eV to 2.86 eV with the increase of the doping concentration of Eu3+. Bi3.4Eu0.6Ti3O12 film possesses maximal remanent polarization, minimal leakage current density, and greatest emission intensity.

The Ba2-xCaxMgTi5O13 (0 ≤ x ≤ 0.3) microwave dielectric ceramics were for the first time prepared via a conventional solid-state reaction method. A small amount of Ca2+ can dissolve into the lattice by forming solid solutions with a monoclinic structure (C2/m) and further influence the sintering behavior, grain growth and microwave dielectric properties of Ba2-xCaxMgTi5O13 ceramics. Both increase of er and decrease of Qxf with x should be associated with increased lattice distortion and uneven grain growth although the sample density and the ratio of the ionic polarizability to the molar volume show little variation. Moreover, the A-site bond valence and τf indicate a close relation in current study, such that the Ca2+substitution can induce an increase of τf values. The optimum microwave dielectric properties of er ∼ 29.3, Qxf ∼ 30,870 GHz (6.5 GHz), and a near-zero τf ∼ +2.1 ppm/°C can be contained in the x = 0.15 ceramic sintered at 1160 °C.

Fully kinetic simulations of arc discharge in vacuum interrupters (VIs) often suffer from prohibitive computational costs. In this article, a hybrid kinetic-magnetohydrodynamic (MHD) transient simulation of vacuum arc using a field-circuit coupling method is proposed for a vacuum circuit breaker. Compared with the fully kinetic simulation method, the advance of the proposed method originates from the so-called hybrid modeling of ion kinetics and electron MHD, where ions and electrons in a VI are separately treated as macroparticles and massless fluids. The simulation results of the arc are consistent with the arc morphology in the discharge plasma experiment. Furthermore, the proposed field-circuit coupling transient model is used to study the number and the decay time of plasma between the electrodes during the interruption process. Finally, we discussed the dielectric-recovery characteristics and the breakdown probability under different voltage frequencies, voltage levels, and electrode gaps.

The magnetoelectric films of Ba0.9Ca0.1TiO3(BCT)/CoFe2O4(CFO) were deposited on Pt(111)/Ti/SiO2/Si(100) substrates by the sol-gel and spin-coating method under three kinds of heat-treatment conditions. It is shown that the heat-treatment conditions have a great effect on the ferroelectric, ferromagnetic and magnetoelectric properties of the composite films. Among the composite films prepared under three kinds of heat-treatment conditions, the composite films prepared under the complete heat-treatment condition (CHC composite films) have the best ferroelectric, ferromagnetic and magnetoelectric properties. They possess largest value of αE (82 mV cm−1 Oe−1). The complete heat-treatment condition is the most appropriate heat-treatment condition for obtaining the best magnetoelectric properties. Ferroelectric phase and ferromagnetic phase can coexist without inter-diffusion at the interface in CHC composite films.

Gastric cancer (GC) is one of the infection-related cancers. Helicobacter pylori and Epstein-Barr virus (EBV) were established risk factors for GC. Recently, there are several reports showing the inconsistent association between hepatitis B virus (HBV) infection and the development of GC. To explore the relationship between HBV infection and the development of GC, we designed a meta-analysis of previous epidemiological studies, a hospital-based case-control study, followed by an immunohistochemistry (IHC) assay of HBV-exposed GC samples. We found that HBV infection was associated with an increased risk of GC based on the meta-analysis. No significant association between HBV infection and GC was detected according to our hospital-based case-control study. Histological examination showed that the gastric epithelium positive for HBx demonstrated a higher nuclear-cytoplasmic ratio compared to those HBx-negative cells. HBx and HBcAg were expressed more in tumors than those in normal counterparts in HBV-exposed subjects, and PD-L1 was lower in GC tissues from HBV carriers than those in HBV clearances. In conclusion, HBV infection may contribute to a higher risk for GC based on the meta-analysis and to the morphological atypia of gastric epithelium by the histological assessment, and GC patients among HBV carriers showed lower expression of PD-L1 may lose the chance for immune checkpoint blockade therapy.

The hybrid membrane bioreactor - nanofiltration treatment process can be an effective approach for treating the landfill leachate, but the residual leachate concentrate highly loaded with the humic substance and salts remains an environmental concern. Herein, a loose nanofiltration membrane (molecular weight cut-off of 860 Da) was used to recover the humic substance, which can act as a key component of organic fertilizer, from the leachate concentrate. The loose nanofiltration membrane showed the high permeation fluxes and high transmissions (>94.7%) for most inorganic ions (i.e., Na+, K+, Cl−, and NO3−), while retaining 95.7 ± 0.3% of the humic substance, demonstrating its great potential in effective fractionation of humic substance from inorganic salts in the leachate concentrate. The operation conditions, i.e., cross-flow rates and temperatures, had more pronounced impacts on the filtration performance of the loose nanofiltration membrane. Increasing cross-flow rates from 60 to 260 L h−1 resulted in an improvement of ca. 7.3% in the humic substance rejection, mainly due to the reduced concentration polarization effect. In contrast, the solute rejection of the nanofiltration membrane was negatively dependent on the temperature. The rejection of humic substance decreased from 96.3 ± 0.3% to 92.0 ± 0.4% with increasing the temperature from 23 to 35 °C, likely due to the enlargement of the membrane pore size and enhancement in solute diffusivity. The humic substance was enriched from 1735 to 15,287 mg L−1, yielding a 91.2% recovery ratio with 85.7% desalination efficiency at a concentration factor of 9.6. The recovered HS had significantly stimulated the seed germination and growth of the green mungbean plants with no obvious phytotoxicity. These results demonstrate that loose nanofiltration can be an effective promising technology to recover the humic substance as a valuable fertilizer component towards sustainable management of the landfill leachate concentrate.

The present work focused on the reduction of the calcium and sulfate ions in a membrane permeate generated from a newly developed two-stage of tight ultrafiltration (TUF) for recovering humic substance from leachate nanofiltration (NF) concentrate by a precipitation process of calcium sulfate dihydrate (gypsum). The operating parameters (temperature and pH), mechanism of precipitating behaviors, and kinetics of this process in the presence of fulvic acid (FA) and magnesium ion simultaneously were investigated. It was found that Ca2+ removal increased with increasing temperature. The decline in pH, especially towards low pH range of 2–3 around the point of zero charge of gypsum, showed a significant effect on gypsum precipitation. Adsorption of FA onto gypsum surface had an important effect on the precipitating behavior of gypsum whose mechanism might be mainly weak interactions of hydrogen bonding and hydrophobic effect at low pH, while electrostatic interactions became dominant at neutral pH. In contrast, retardation effect of Mg2+ ion on gypsum precipitation was negligible at pH 2.5. The soluble calcium removal during precipitation process corresponded with first order rate equation. The results indicated that the optimal operating parameters were found at 70 °C and around pH 2.5, which can be applied to the scale-up and industrial design of the precipitation process of gypsum for removing the calcium and sulfate ions in the presence of FA and magnesium ion.

In the control system of a quantum gravimeter, the optical signal containing phase information is weak and usually at the nV level. This situation puts forward high requirements for the measurement performance of the system. As the coupling input component of the measurement system, the noise level of the preamplifier has a dramatic influence on the noise performance. In this paper, the input current signal is provided by the photodiode. According to the photodiode output characteristics, we design three preamplifiers with different gain and bandwidth, which is verified by the optical system. Under the condition of meeting the design requirements, the noise performance is compared with the common commercial detector Model 2307. The results show that the noise performance of the photoelectric converter designed in this paper is about 1.5 times that of model 2307.

Cadmium (Cd) is a widely distributed endocrine disruptor and has been reported to be closely correlated to the pathogenesis of diabetes. Since pancreatic β-cells loss and dysfunction are central to pathogenesis of diabetes, studying Cd toxicity on pancreatic β-cells and its molecular mechanism is an important scientific issue. However, less attention has been payed to study how Cd induces pancreatic β-cells death and dysfunction in recent years. Thus, our study aims to explore the toxic mechanism of Cd treatment on pancreatic β-cells using both cellular and animal models. Firstly, it was confirmed that Cd induced decreased cell viability and insulin secretion in a dose-and time-dependent manner in MIN6 cells. To explore the underlying mechanism, transcriptomic analysis was employed to screen the differentially expressed genes and disturbed metabolic pathways. Go and KEGG analysis showed that Cd exposure triggered ferroptosis process in MIN6 cells. We further validated that Cd led to GSH depletion, Gpx4 reduction, lipid peroxidation, mitochondrial membrane potential loss and ultrastructural damage at mitochondrial level. Since immune system process was also perturbed based on GO analysis, we found that Cd activated Ager/Pkc/p65 inflammatory process. Moreover, ferroptosis inhibitor Fer-1 could effectively antagonized the activation of Ager-mediated immune process. It was also revealed that Cd induced iron accumulation as well as decreased Gpx4 expression in mice islets. We also uncovered that Cd led to systemic and pancreatic inflammation as early as third week after Cd exposure. Our study emphasizes the importance of ferroptotic cell death on Cd-induced systemic chronic inflammation. A novel target is provided to prevent Cd-induced pancreatic β-cells dysfunction and improve the chronic inflammatory state for prediabetes prevention.

According to specific formulas, the mixing of rubber samples occurs by two methods: open mixing and internal mixing. The effects of frequency, mixing process, carbon black (CB) content, zinc oxide (ZnO) content, and stearic acid (SA) content on the dielectric properties of rubber materials were studied. The results showed that the effects of the mixing process on the dielectric properties of the rubber samples cannot be ignored, and the appropriate mixing process should be selected when preparing the required rubber materials. The dielectric constant and loss factor of the rubber samples vary depending on the frequency. The dielectric constant had a peak and valley value, while the loss factor only had a peak. The dielectric constant and loss factor of rubber samples were significantly affected by the content of CB, ZnO, and SA. The peak frequency decreased with the increase in CB content, however, the dielectric constant increased with an increase in CB content. The higher the ZnO content, the lower the peak frequency. In addition, the dielectric constant and loss factor increased with an increase in ZnO content. The higher the SA content, the greater the peak frequency. In addition, the dielectric constant and loss factor decreased with an increase in SA content. It is hoped that the experimental results obtained can provide guidance for the study of the dielectric properties, microwave absorption properties, and microwave heating characteristics of rubber polymers.