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In the health assessment for complex systems, system attributes refer to the indicators or components having an impact on the health state of the system. When assessing the health state of complex systems, the relative importance of system attributes should be accurately modeled, otherwise incorrect results may occur. Especially for some complex systems with small samples, data-driven methods are prone to overfitting. In this article, a new method using belief rule base (BRB) is proposed to model the relative importance of system attributes while assessing the health state. As an interpretable modeling tool, BRB constructs nonlinear mapping relationships between system attributes and health state. A data-knowledge hybrid-driven ensemble feature selection (DKH-EFS) method is developed to calculate the relative importance of the system attributes, namely attribute importance (AM). A random sensitivity analysis (RSA) method of the model output to the input of BRB is proposed to calculate the feature importance (FI) of BRB. A new parameter optimization model considering the consistency between the AM and FI is introduced to improve the modeling ability of BRB for the AM. A case study on the health assessment of the fiber optic gyroscope (FOG) validates the proposed method. [ABSTRACT FROM AUTHOR]

To optimize the structure of an air route network, accurate forecasting of future new routes is vital given the rapid growth in demand for air transportation. Based on the theory and method of link prediction, considering the joint influence of network endogenous factors and external attributes, we construct a system of network endogenous factors and external attribute indices and explore the prediction effect of each index. We further construct a prediction index system, explore the prediction effect of coupled indices, design a particle swarm algorithm to determine the weights of each index, and propose a coupled link prediction model based on particle swarm optimization (PSO-CLP). A comparison of the prediction accuracy of this model with the dual-indicator coupled link prediction model and the traditional link prediction model is also conducted to test the stability and reasonableness of the PSO-CLP model. In this study, we use the 2015–2020 Chinese air route network as an example. The instance test shows that the PSO-CLP models significantly outperform the traditional link prediction models and dual-indicator coupled link prediction models in terms of prediction accuracy, stability and computational simplicity, among which the PSO-CLP model, which considers both endogenous factors and external attributes, such as the RWR + Sor + Pop and RWR + RA + GDP indices, has the best forecasting effect. The PSO-CLP model is an effective tool for route prediction, providing a new perspective on route link prediction and air route network optimization. [ABSTRACT FROM AUTHOR]

The Drosophila abnormal wing discs (awd) gene encodes the subunit of a protein that has nucleoside diphosphate kinase (NDP kinase) activity. Null mutations of the awd gene cause lethality after puparium formation. Larvae homozygous for such mutations have small imaginal discs, lymph glands, and brain lobes. Neither the imaginal discs nor the ovaries from such null mutant larvae are capable of further growth or normal differentiation when transplanted into suitable host larvae. This null mutant phenotype can be entirely rescued by one copy of a transgene that has 750 bp of awd upstream regulatory DNA fused to a full-length awd cDNA. Tissue-specific expression of AWD protein from this rescue transgene is identical to tissue-specific expression of [Beta]-galactosidase from a reporter transgene that has the same regulatory region fused to the bacterial lac Z gene. However, this rescue transgene or reporter transgene expression pattern is only a subset of the endogenous pattern of expression detected by either in situ hybridization or immunohistochemistry. This suggests that awd is normally expressed in some tissues where it is not required. The null mutant phenotype cannot be rescued at all by a transgene that has 750 bp of awd upstream regulatory DNA fused to a full-length awd cDNA with a mutation that eliminates NDP kinase activity by replacement of the active site histidine with alanine. This suggests that the enzymatic activity of the AWD protein is necessary for its biological function. The human genes nm23-H1 and nm23-H2 encode NDP kinase A and B subunits, respectively. The protein subunit encoded by either human nm23 gene is 78% identical to that encoded by the Drosophila awd gene. Transgenes that have the 750-bp awd upstream regulatory DNA fused to human nm23-H2 cDNA but not to nm23-H1 cDNA can rescue the imaginal disc phenotype and the zygotic lethality caused by homozygosis for an awd null mutation as efficiently as an awd transgene. However, rescue of female sterility requires twice as much nm23-H2 expression as awd expression. This implies that the enzymatic activity of the AWD protein is not sufficient for its biological function. The biological function may require nonconserved residues of the AWD protein that allow it to interact with other proteins.

The abnormal wing discs (awd) gene of Drosophila is homologous to the nm23 gene of mammals since both the genes are able to encode nucleoside diphosphate kinases (NDP kinases). The analysis of awd focussed on enzyme activity in extracts which regulates the accumulation of AWD/NDP kinase during ordinary growth. Throughout the pupal and larval growth, an unchanging level of activity in maintained. The awd gene expression is essential to tumor formation and proliferation. A great proportion of awd gene-expressing cells in mutant brains is responsible for the small amounts of AWD/NDP kinase in lgl- mutant brains.

Microbes are widespread in the sea that covers more than two-thirds of the earth's surface and most microorganisms living in the marine environment have yet to be cultured. Previous studies showed that drying treatment, a strategy of sample pre-treatment widely applied in microbial isolation and incubation, may alter the cultivable microbial diversity, such as Actinomycetota , essential for exploring novel secondary metabolites from the marine environment, isolated from drying-treated samples. However, whether drying treatments actually can change microbial community diversity and how the drying treatments of samples influence the cultivable microbial diversity of marine samples have not yet adequately been evaluated. Here, three marine sediment samples were dried and incubated at 28 ºC, 37 ºC, and 45 ºC, and the microbial diversity was assessed with high-throughput sequencing. Our results suggested that drying treatments had different effects on different genera and some potential novel species could be cultured only from drying-treated samples, including the novel members from the families Paenibacillaceae and Thermoactinomycetaceae. Non-metric multidimensional scaling analysis showed that the treated samples were clustered according to the cultivation temperatures rather than the drying conditions at high cultivation temperatures. However, at the cultivation temperatures of 28 ºC, drying treatments were the larger separation between cultivable microbial communities in the process of microbial isolation. These results showed that the drying treatments influenced the cultivated microbes in a taxon-specific pattern and extended potential novel taxa. Combining high-throughput sequencing to various drying conditions and incubation temperatures, this study provides new insight into the effects of drying treatment on the cultivable microbial diversity of marine sediments. [Display omitted] • The drying treatments influenced the cultivated microbes in a taxon-specific pattern and extended potential novel taxa. • Compared with high cultivation temperatures, the drying treatments seemed to be of less significance in the isolation. [ABSTRACT FROM AUTHOR]

Auxetic structures with negative Poisson's ratio (NPR) have been widely studied because of their great potentials in energy absorption. In order to further understand the 3D auxetic structures, especially the 3D re-entrant honeycombs, the crushing response of metallic 3D re-entrant honeycomb (3D-RH) is theoretically studied in this paper. First, the finite element (FE) model of the 3D-RH was built and validated. The numerical simulation results show that the 3D-RH exhibits different deformation modes under low- and high-speed crushing. Secondly, a set of numerical simulations was used to determine the critical velocity that distinguishes the two deformation modes. Based on the predicted deformation profile, the crushing strength of 3D-RH under low- and high-speed crushing was derived in the form of theoretical equations. The relative errors between the theoretical and numerical results are less than 10%. Thirdly, the structural parameters were studied to reveal their effects on the crushing strength of 3D-RH. The results showed that the oblique wall length and cell wall thickness have significant effects on the crushing strength, while the cross length and cell wall width have little effect on the crushing strength. In addition, the re-entrant angle has no obvious effect on the low-speed crushing strength, but has a significant effect on the high-speed crushing strength. Finally, considering the rotational symmetry of the 3D-RH unit, the 3D-RH-nRP unit was found, which is a new type of 3D re-entrant unit with multiple re-entrant parts. The corresponding equations of crushing strength were derived. The FE results showed that the equations can well estimate the crushing strength of 3D-RH-nRP structures. • The crushing strength of 3D re-entrant honeycomb was theoretically studied. • Effects of geometrical parameters on the crushing strengths were analyzed. • A type of 3D re-entrant honeycomb with multiple re-entrant parts was proposed. [ABSTRACT FROM AUTHOR]

• Five novel Thermus species were isolated from Tibet hot spring. • Incomplete denitrification roles of five novel Thermus species. Biological denitrification is a significant process in nitrogen biogeochemical cycle of terrestrial geothermal environments, and Thermus species have been shown to be crucial heterotrophic denitrifier in hydrothermal system. Five Gram-stain negative, aerobic and rod-shaped thermophilic bacterial strains were isolated from hot spring sediments in Tibet, China. Phylogenetic analysis based on 16S rRNA gene and whole genome sequences indicated that these isolates should be assigned to the genus Thermus and were most closely related to Thermus caldifontis YIM 73026T, and Thermus brockianus YS38T. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between the five strains and the type strains of the genus Thermus were lower than the threshold values (95% and 70%, respectively) recommended for bacterial species, which clearly distinguished the five isolates from other species of the genus Thermus and indicated that they represent independent species. Colonies are circular, convex, non-transparent. Cell growth occurred at 37–80 °C (optimum, 60–65 °C), pH 6.0–8.0 (optimum, pH 7.0) and with 0–2.0% (w/v) NaCl (optimum, 0–0.5%). Denitrification genes (narG , nirK , nirS , and norB genes) detected in their genomes indicated their potential function in nitrogen metabolism. The obtained results combined with those of morphological, physiological, and chemotaxonomic characteristics, including the menaquinones, polar lipids, and cellular fatty acids showed that the isolates are proposed as representing five novel species of the genus Thermus , which are proposed as Thermus hydrothermalis sp. nov. SYSU G00291T, Thermus neutrinimicus sp. nov. SYSU G00388T, Thermus thalpophilus sp. nov. SYSU G00506T, Thermus albus sp. nov. SYSU G00608T, Thermus altitudinis sp. nov. SYSU G00630T. [ABSTRACT FROM AUTHOR]

Due to the negative Poisson's ratio (NPR) effect, auxetic structures such as re-entrant honeycombs show excellent energy absorption and force mitigation capabilities under crushing load. Compared with two-dimensional (2D) auxetic structure, three-dimensional (3D) ones are expected to have better performance, but they are more difficult to fabricate. In this study, a hierarchical fabrication method for metallic 3D re-entrant honeycomb (3D-RH) using traditional manufacturing techniques is proposed. A 3D-RH specimen was crafted and tested under quasi-static crushing condition. The finite element (FE) model was established and verified by the experimental results. The numerical simulation results showed that the friction condition between 3D-RH specimen and loading surfaces has a great influence on the deformation mode of specimen. Moreover, the energy absorption capability of 3D-RH was numerically compared with a similar structure, i.e., the warp and woof periodic auxetic cellular (WWPAC) structure. The results showed that the specific energy absorption (SEA) of 3D-RH is 1.59 times that of WWPAC and the 3D-RH outperformed the latter in lightweight performance. Finally, the blast resistance of 3D-RH sandwich panel was numerically studied. Compared with 2D re-entrant expanded honeycomb (2D-REH) core, 3D-RH core can reduce the maximum deflection of lower face-sheet by 14.6%, and increase SEA by 20.5%, showing better blast resistance. • A hierarchical fabrication method of metallic 3D-RH has been proposed. • The method uses traditional manufacturing techniques to reduce fabrication cost. • The friction coefficient can alter the deformation mode of 3D-RH under crushing. • The energy absorption per unit mass of 3D-RH is greater than that of the WWPAC. • The 3D-RH shows better anti-blast performance than the 2D-REH. [ABSTRACT FROM AUTHOR]

Highlights: [•] β-NaYF4:Yb3+,Tm3+@TiO2 core@shell composites have been successfully fabricated. [•] The upconversion of energy transfer from β-NaYF4:Yb3+,Tm3+ to TiO2 was confirmed. [•] β-NaYF4:Yb3+,Tm3+@TiO2 core@shell composites exhibit efficient photocatalysis in NIR. [•] The composites show no obvious deactivation after four recycles experiments. [ABSTRACT FROM AUTHOR]

The kinetics and mechanism of synergistic oxidation of sulfite solution by ozone and oxygen was studied in this work. Among the oxidation process, gas–liquid mass transfer of oxygen can be regarded as the rate-determining step. Sulfite radical is induced by ozone to be produced, and subsequently reacts with oxygen with a rapid rate. Additionally, a kinetic model is established with investigating the various operating parameters and mass transfer process. [Display omitted] • The kinetics of synergistic oxidation of sulfite solution by ozone and oxygen. • Gas-liquid mass transfer of oxygen is the rate-determining step. • A rapid chemical transform proceeds in solution. • The developed kinetic model provides an acceptable simulation for oxidation rates. Kinetics for the synergistic oxidation of sulfite containing solution by ozone and oxygen was studied in this work. A model including the macro oxidation of sulfite solution, the gas–liquid mass transfer of ozone and oxygen, and chemical reaction in the liquid phase was developed and established. The model considered the following variables: sulfite concentration, partial pressure of ozone or oxygen, pH of the sulfite solution, ionic strength of the medium, reaction temperature, and residence time. For the oxidation processes, mass transfer of oxygen was found to be the rate-determining step as the transfer of ozone and chemical transformation was found to proceed rapidly. In addition, the simulation results for the oxidation rates obtained from this model via comparison of the experimental results with the predicted values were found to be acceptable. The developed kinetic model is beneficial for further understanding of the oxidation mechanism of sulfite solution. [ABSTRACT FROM AUTHOR]

To explore the potential targets underlying the effect of rosuvastatin on heart failure (HF) by utilizing a network pharmacology approach and experiments to identify the results. PharmMapper and other databases were mined for information relevant to the prediction of rosuvastatin targets and HF-related targets. Then, the rosuvastatin-HF target gene networks were created in Cytoscape software. Eventually, the targets and enriched pathways were examined by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Furthermore, we constructed an HF animal model and used rosuvastatin to treat them, identifying the changes in heart function and related protein expression. We further used different cells to explore the mechanisms of rosuvastatin. Thirty-five intersection targets indicated the therapeutic targets linked to HF. GO analysis showed that 481 biological processes, 4 cellular components and 23 molecular functions were identified. KEGG analysis showed 13 significant treatment pathways. In animal experiments, rosuvastatin significantly improved the cardiac function of post-myocardial infarction mice and prevented the development of HF after myocardial infarction by inhibiting IL-1Β expression. Cell experiments showed that rosuvastatin could reduce the expression of IL-1B in HUVEC and THP-1 cells. The therapeutic mechanism of rosuvastatin against HF may be closely related to the inhibition of the expression of apoptosis-related proteins, inflammatory factors, and fibrosis-related genes. However, IL-1Β is one of the most important target genes. [ABSTRACT FROM AUTHOR]

• A protect system containing auxetic sandwich panel and covering plate was proposed. • Parametric study was conducted concerning the geometric and thickness parameters. • A multi-scale optimization was performed to improve the anti-blast performances. • The multi-scale optimization yielded better compromised design and cost less effort. In this paper, a protect system consists of a re-entrant hexagon honeycomb cored sandwich panel and a homogenous steel plate was firstly proposed. The parametric study including boundary conditions, geometric and thickness parameters of the protect system was conducted. It was found that, under the presented set-up, the boundary conditions did not affect the energy absorption of the protect system, they only altered the internal energy distribution among the protect system. Finally, a novel multi-scale optimization was conducted to further improve the performance of the protect system. Another conventional multi-objective optimization was also conducted for comparison. The results showed that, by affording less computational effort, the multi-scale optimization improved the ASEA (areal specific energy absorption) by 4.9% and reduced MaxD (maximum displacement) by 1.8%, comparing to the conventional multi-objective optimization. [ABSTRACT FROM AUTHOR]

Excess O 3 is invariably used to ensure the effective oxidation of NO in the industrial simultaneous desulfurization and denitration through combined ozone oxidation and absorbent scrubbing. O 3 is difficult to fully react with NO considering the short residence time of flue gas, remaining O 3 transport into the subsequent absorption device, and even its escape into the atmosphere. To study the influence of excess O 3 on NO 2 absorption in sulfite solution, we simulated an integrative process of pre-oxidation and post-absorption. NO 2 removal efficiency was improved from 36.1% to 66.5% as the mole ratio of O 3 /NO increased from 1.0 to 1.6. Additionally, the effects of temperature, pH, and reactant concentration with the remaining O 3 on NO 2 removal were evaluated. After 5 h of steady absorption, the concentration of total N species in the adsorbent was 82.8 mmol/L at a O 3 /NO mole ratio = 1.6. However, this concentration was only 51.4 mmol/L at a O 3 /NO mole ratio = 1.0, indicating that more NO 2 was absorbed, and the gas-liquid transfer of NO 2 was enhanced by the excess O 3 via oxidizing NO 2 − into NO 3 −. This work contributes to re-utilizing remaining O 3 and reducing O 3 escape in simultaneous desulfurization and denitration technology. This research studied the role of excess O3on NO2absorption in sulfite solution and the corresponding mechanism. NO2removal efficiency was enhanced with excess O3in sulfite solution. NO2-was removed from sulfite absorption system via the oxidation ofNO2-into NO3-by excess O3. The chemical equilibrium of the reaction between NO2and SO32-was shifted by removing NO2-, resulting in the NO2absorption that containing gas-liquid transfer and chemical reaction was improved. Unlabelled Image • NO 2 absorptionwas improved with excess O 3 • Absorption equilibrium was shifted • NO 2 gas-liquid transfer was modified [ABSTRACT FROM AUTHOR]

Hyperthecosis syndrome is a common endocrine system metabolic disorder in women of childbearing age. The main symptoms are elevated androgen levels, abnormal ovulation, and excessive oxidative stress. Currently, there is no effective treatment for hyperthecosis syndrome. α(1)-adrenergic receptor (ADRA1) is involved in the metabolic pathway of ovarian steroid hormone. This study studied the mechanism of the ADRA1 inhibitor terazosin in the LH-induced bovine theca cells in vitro. We found that terazosin regulates the expression of steroidogenic factor 1 (SF1) and downstream genes through the ERK1/2 pathway, reducing androgen content. Terazosin promotes the expression of HSP90 and reduces the activity of iNOS. In addition, Terazosin up-regulates the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream gene γ-GCS, which improves the ability of theca cells to resist oxidative stress. This study provides a reference for the treatment of human hyperthecosis syndrome. Schematic illustrates a proposed pathway by which terazosin regulates androgen production in LH-induced bovine theca cells. Terazosin enhancing the HSP90 expression of bovine theca cells. Image 1 • Terazosin reduces androgen production in LH-induced theca cells. • Terazosin regulates SF1 expression in theca cells. • Terazosin promotes HSP90 expression in LH-induced theca cells. [ABSTRACT FROM AUTHOR]

Protecting building, critical infrastructure and military vehicles from Improvised Explosive Devices (IEDs) has become a critical task. This study aims to examine the performance of a new protective system utilizing auxetic honeycomb-cored sandwich panels for mitigation of shock loads from close-in and contact detonations of high explosives. Both field blast tests and drop weight tests were performed using the proposed sandwiches as a shield for concrete panels in combination with conventional steel protective plates. The combined shield was found to be effective in protecting reinforced concrete structures against severe impact and close-in blast loadings. The honeycomb core with re-entrant hexagonal cells shows evident auxetic characteristics which contribute substantially to outstanding force mitigation and blast-resistance performances of such sandwich panels. Numerical simulations showed good agreement with the experimental results. The proposed auxetic panels were found to perform better than conventional honeycomb panels of the same size, areal density and material. Both were found to boost the energy absorption of the monolithic steel plate by a factor of 2.5 by changing its deformation pattern under close-in blast loading. In addition, a combination of the steel plate and an auxetic sandwich panel has aerial specific energy absorption ( ASEA ) higher than either of them, showing great potential for the development of lightweight blast protection of civil, mining, military, nuclear infrastructure and vehicles. [ABSTRACT FROM AUTHOR]

—In aerospace engineering, implementing interpretable fault diagnosis technology is critical for improving the credibility of diagnostic results and ensuring the reliability of complex electromechanical systems. As a typical interpretable modeling method, the belief rule base (BRB) approach still faces two challenges that need to be addressed for its application in interpretable fault diagnosis: 1) The lengthy rule structures raise the cost of model interpretability, and 2) over-optimization of parameters diminishes the interpretability. To solve these problems, this paper proposes a modified micro-belief rule structure and develops a new micro-belief rule base (MBRB) model based on this structure. In addition, considering the independence of rules and the correlations between multiple BRBs, a cautious conjunctive rule-based reasoning process is established as the inference engine of MBRB. Moreover, an interpretable optimization method based on projection covariance matrix adaptive evolutionary strategy (PCMAES-I) is proposed for the MBRB model to balance model interpretability and diagnostic accuracy. Finally, the availability and effectiveness of the proposed MBRB is verified through an electromagnetic relay experiment. [ABSTRACT FROM AUTHOR]

Magnetic memory inspection technology is an effective method for detecting early damage in ferromagnetic materials. However, the commonly used force-magnetic coupling models are insufficient for analyzing the distribution characteristics of magnetic signals in ferromagnetic material welds. This study first analyzes the influence of metal phase transformation and residual stress on the magnetic hysteresis characteristics of materials. Based on the principle of magnetic hysteresis characteristics, the magnetic charge density under the combined action of stress and phase transformation is determined, and a magnetic memory analysis model is established for multi-parameter coupling. The study quantitatively calculates the effects of phase transformation volume fraction, residual stress, the lift-off effect, and cracks on the magnetic signal features at welds. The research results show that the magnetic memory signals at welds exhibit extreme values in the tangential component and sinusoidal fluctuations with zero-crossings in the normal component. The peak-to-peak values of both the normal and tangential components of the magnetic signal increase with an increase in metal phase transformation and residual stress, while they decrease with the increase of the lift-off effect. When cracks appear in the weld, the normal component exhibits a double-peak and valley structure, with the inner side representing crack features and the outer side representing weld features. The tangential component shows a maximum value at the center of the crack. Based on the peak and valley values of the magnetic signal, a damage grade index F is determined. The damage index F can characterize the level of weld damage, decreasing approximately linearly with increasing stress. • This study analyzed how phase transformation volume fraction, residual stress, and cracks at the weld influence the magnetic hysteresis characteristics of the material. • A multi-parameter coupled magnetic memory field analysis model considering residual stress, metal phase transformation, and cracks was developed. • The accuracy of pipeline damage assessment based on magnetic signals can be improved by determining the damage grade index F. [ABSTRACT FROM AUTHOR]

Uterine transplantation (UTx) is the only effective treatment for uterine infertility patients to become genetic mothers. After decades of research, the surgical methods of UTx are very developed. There are numerous factors that affect the results of UTx, such as selection of the donor uterus before transplantation, immunosuppressive therapy post-transplantation, rejection monitoring, and immune tolerance. Studies have shown that immune rejection is a crucial factor affecting the survival rate after organ transplantation. Unlike liver or kidney transplantation, the aim of UTx is to obtain a functional uterus that is able to support successful pregnancy and birth of a healthy fetus. Because of the unique purpose of UTx, its immunosuppressive program is relatively specialized. Some immunosuppressive agents can cause perinatal complications, and inducing immune tolerance is necessary to resolve these side effects. Further understanding of the immune mechanism of UTx and the continuous development of new immunosuppressive agents, combined with the application of assisted reproductive technology, will be more conducive to the realization of UTx to breed offspring. [ABSTRACT FROM AUTHOR]

Owing to its sustainability and low cost, direct revegetation (DR) has been considered a promising alternative to capped revegetation (CR) for dealing with the serious environmental problem derived from various types of mine wastelands that are widespread in the world. However, a direct comparison of the performance of these two revegetation approaches for reclamation of extremely acidic mine wastelands and the underlying mechanisms is still lacking. To bridge this critical knowledge gap, we established 5000 m2 of vegetation on a highly acidified (pH < 3) Pb/Zn mine tailings pond employing both CR and DR schemes (2500 m2 for each scheme). We then profiled the structure, ecological network and function of soil microbial communities associated with two dominant plant species of the vegetations via high-throughput sequencing. Our results showed that CR and DR achieved a vegetation coverage of 59.7% and 90.5% within two years, respectively. This pattern was accompanied by higher concentrations of plant nutrients and lower acidification potentials in topsoils of the rhizospheres of the vegetation established by DR compared to those of CR. Revegetation approach, rather than plant identity, mostly affected the structure, ecological network and function of soil microbial community in the mine tailings pond. Rhizosphere soils of the vegetation established by DR generally had higher microbial diversity, higher relative abundances of dominant microbial phyla (e.g. Nitrospirae) that can aid plant uptake of nutrients, more complicated microbial interactive networks and more microbial genes responsible for nutrient cycling than those by CR. As the first report on a direct comparison of CR and DR schemes for reclamation of an extremely acidic mine wasteland, our study has important implications for not only the understanding of microbial ecology in revegetated mine wastelands but also the further development of sustainable revegetation schemes. Unlabelled Image • We established 5000 m2 of vegetation on replicated plots of an acidic tailings pond. • Performances of direct and capped revegetation were compared for the first time. • Direct revegetation performed better than capped revegetation in the first two years. • Direct revegetation created a more complex soil microbial interactive network. • Soil microbes of direct revegetation showed higher potentials for nutrient cycling. [ABSTRACT FROM AUTHOR]

Leydig cells synthesize and secrete testosterone, and are regulated by Sertoli cells. These two cell types may work together to regulate testicular androgen production. Studies have shown that Leydig cell androgen synthesis can be dramatically enhanced by Sertoli cells in the presence of melatonin, which can regulate the secretory function of Leydig and Sertoli cells. However, the molecular mechanism of melatonin-regulated Leydig cell androgen production via Sertoli cells remains unclear. Here, we found that 10 −7 M melatonin increased testosterone production in co-cultured Leydig and Sertoli cells isolated from sheep. Melatonin increased the expression of stem cell factor and insulin-like growth factor-1 and decreased estrogen synthesis in Sertoli cells. Melatonin promoted insulin-like growth factor-1 and decreased estrogen content via the membrane melatonin receptor 1. It also enhanced stem cell factor expression via the retinoic acid receptor-related orphan receptor alpha. Addition of PD98059, a MEK inhibitor, to Sertoli cell culture demonstrated that the melatonin upregulation of insulin-like growth factor-1 and downregulation of estrogen may be through the MEK/extracellular signal-regulated kinase pathway. Together, these results suggest that melatonin may function through modulating melatonin receptor 1-regulated insulin-like growth factor-1 expression, as well as melatonin receptor 1-induced suppression of estrogen synthesis to increase androgen production in co-cultured Leydig and Sertoli cells. [ABSTRACT FROM AUTHOR]

Sperm cells can be damaged during the semen cryopreservation process, decreasing their fertilizing ability. Physical damage and oxidative stress may occur during the freeze–thawing process. Antioxidants such as the native antioxidant melatonin can potentially improve cryopreservation outcomes. In this study, we added melatonin to cryoprotectant to examine its effect on frozen–thawed human sperm. We found that adding 0.1 mM melatonin to cryoprotectant significantly increased sperm viability (24.80 ± 0.46% vs. 20.97 ± 1.27%, P < 0.05) and membrane integrity ( P < 0.05), and decreased intracellular reactive oxygen species and lipid peroxidation damage. Furthermore, mRNA levels of the transcription factor NF-E2-related factor-2 and its downstream genes were significantly increased. Resistance to oxidative stress was enhanced and expression of the antiapoptotic gene Bcl-2 was increased by inclusion of 0.1 mM melatonin in the cryoprotectant. Moreover, 0.1 mM melatonin upregulated the expression of heat shock protein 90 (HSP90), which confers resistance to stressors in frozen–thawed sperm. Results obtained upon addition of inhibitors of melatonin receptors (luzindole and 4-P-PDOT) and an HSP90 inhibitor (geldanamycin) in the cryoprotectant demonstrated that melatonin promoted HSP90 translation via the melatonin receptor MT1 and increased adenosine triphosphate levels, thus increasing the viability of thawed sperm. [ABSTRACT FROM AUTHOR]

The magnetic flux leakage (MFL) internal detection is one of the most effective methods for assessment of long-distance oil and gas pipelines. To quantify the outer surface defect through MFL signals, which are affected by pipe wall and its shielding effect, propagation compensation factor (PCF) was proposed to apply to a classical magnetic charge model. Using the established model for outer surface defects in long-distance oil and gas pipelines, characteristics of MFL signals with different wall thicknesses and defect sizes along with their propagation patterns were analyzed. To verify the analytical model, X70 pipes with different wall thicknesses were used for systematic experiments. The results showed that the pipe wall thickness had a significant attenuation effect on the MFL signals of external defects. As the wall thickness increased from 7 to 17 mm, the MFL signals exhibited a first-order exponential decay, with a maximum error of 25.8% and a minimum error of 2.5%. When the defect depth increased from 0.6 to 7.2 mm, the MFL signals showed a first-order exponential upward trend, with a maximum error of 18.8% and a minimum error of 2.0%. This study effectively described the propagation characteristics of MFL signals of outer surface defects, and facilitated identification and quantitative evaluation of outer surface defects. • The propagation compensation factor is introduced to quantify outer surface defects in long-distance oil and gas pipelines. • The relationship between propagation compensation factor and different wall thicknesses and defect depths are discussed. • The variation of MFL signals with different wall thicknesses and defect sizes are studied. • The propagation characteristics of MFL signals of external surface defect are investigated. [ABSTRACT FROM AUTHOR]

Genetic modification provides a means to enhancing disease resistance in animals. Toll-like receptor 4 ( TLR4 ), a member of the TLR family, is critical for the recognition of lipopolysaccharide (LPS)/endotoxin from Gram-negative bacteria by host immune cells, which initiates cell activation and subsequently triggers a proinflammatory response to the invading pathogens. In this study, the first generation of genetically modified (GM) sheep overexpressing TLR4 was produced by microinjection for better disease resistance. Compared with wild-type (WT) rams, the GM rams have similar growth performance, basic semen quality and spermatozoon ultrastructure. The offspring birth rates after cervical artificial insemination were also similar between GM (90.32%) and WT (92.38%) rams. Overall, the presence and expression of the TLR4 transgene in the genome did not appear to interfere with normal semen production, reproductive traits and the ability of transgene transmission to offspring. The expression levels of TLR4 , tumor necrosis factor and interferon gamma genes in monocyte/macrophages from GM sheep were significantly higher than that from WT sheep at early stages after LPS stimulation. The GM offspring born from the founder transgenic ram inseminated ewes had similar survival rate with WT offspring (88.89% vs 84.86%) at weaning. The TLR4 transgene showed no deleterious effects on growth performance, reproductive traits and offspring survivability of GM rams. Therefore, the GM sheep overexpressing TLR4 provide a powerful experimental model for analyzing function of TLR4 in vivo during infection and inflammation. [ABSTRACT FROM AUTHOR]

• Sandwich protection system against blast loads containing graded re-entrant circular (REC) auxetic core. • Compared with re-entrant (RE) core with same mass, REC core can reduce MaxD by 2.2% and increase EA by 5.7%. • Effects of geometric parameters and gradient parameters on blast-resistance of REC cored protection system. • After multi-objective optimization, MaxD of graded core sandwich panel is reduced by 33.0%. Explosion threat has a devastating impact on buildings, warships, vehicles and human lives, which puts forward urgent requirements for the development of explosion protection systems. In this study, a sandwich protection system against close-range blast loads containing graded re-entrant circular (REC) auxetic core was proposed, and its blast-resistance performance was investigated based on the numerical methods validated by the field blast test results in the literature. Numerical results showed that compared with the conventional re-entrant (RE) core with the same mass, the REC core can reduce the maximum displacement (MaxD) of the back panel by 2.2% and increase the energy absorption (EA) of the system by 5.7%. If the two cores share the same cell wall thickness, the REC core can reduce MaxD by 28.0% and increase EA by 2.1%. In addition, the effects of geometric parameters, thickness parameters and gradient parameters on the blast-resistance of REC cored protection system were examined. The results indicated that reducing the thickness of the cell wall, that is, reducing the core density, can effectively improve the blast-resistance performance. Finally, to further improve the performance of the proposed explosion protection system, multi-objective optimizations were carried out for the system with uniform and graded REC cores. The results showed that compared with the baseline model, the MaxD of the optimized uniform and graded core sandwich panels is reduced by 20.0% and 33.0%, while the areal specific energy absorption (ASEA) is increased by 21.2% and 23.1%, respectively. The present study shows that the re-entrant circular auxetic cored sandwich structure has great potential in blast protection applications. [ABSTRACT FROM AUTHOR]

In order to investigate the heterogeneous detonation characteristics of aluminum particles/JP-10/air mixtures, the gas–solid two phase flow and detonation models were established using the discrete phase model (DPM) and turbulent combustion model, and detonation properties of the aluminum particles/JP-10/air mixtures were simulated. At stoichiometric concentrations of the solid particle–gas mixtures, and four different mass ratios (100% aluminum particles/air, 60% aluminum particles/40% gaseous JP-10/air, 40% aluminum particles/60% gaseous JP-10/air, 100% gaseous JP-10/air), results reveal that obvious reaction relaxation phenomenon exists in aluminum particles detonation process, however, addition of gaseous JP-10 to aluminum particles obviously contributes to higher steady detonation propagation velocity and extended reaction zone width. Furthermore, 60% aluminum particles/40% JP-10/air mixture achieves the highest detonation velocity up to 2128 m/s, detonation pressure of 3.7 MPa, efficiently enhanced reaction zone width of 0.369 m, and the reaction times of JP-10/air and aluminum particles/air of 2.07 μs and 5.65 μs, respectively. [ABSTRACT FROM AUTHOR]

• Heteroatom nitrogen affect the performance of Li–O 2 batteries significantly. • The discharge and charge processes are optimized with the introduction of nitrogen. • Nano-sheet Li 2 O 2 depositing on nitrogen doped cathode benefits its decomposition. • Influence mechanism of nitrogen on the battery performance was studied systematically. Admitting that the validity of heteroatom doped transition metal oxides in improving electrochemical performances in Li–O 2 battery, the reasons for the improvement remains ambiguous. In this study, nitrogen as a heteroatom is introduced to the CoO nanoneedle arrays grown on the carbon cloth (N CoO NAs/CC), and the effects of nitrogen on the electrochemical behavior of Li–O 2 batteries are comprehensively studied by experimental and theoretical calculations. With the incorporation of nitrogen, the catalytic activity of the prepared cathode is heavily enhanced through a combined set of factors, including enhanced electronic conductivity, optimized reactant/intermediates affinity, as well as improved reaction kinetics. In addition, further investigation on the morphology of the discharge products demonstrates that the introduction of nitrogen can also promote the solvation discharge path of the battery, which is conducive to the release of the battery capacity. Moreover, the introduction of nitrogen makes the discharge products on the cathode show nano-sheet structure, which is easier to be decomposed during charging. The electrochemical performances of the N CoO NAs/CC cathode including battery cycle efficiency, capacity and cycle stability are heavily enhanced due to the above advantages. The combination of doping engineering and electrochemical performances provides an ingenious way to develop a new type of economic and efficient cathode for Li–O 2 batteries. [Display omitted] [ABSTRACT FROM AUTHOR]

Li-CO 2 batteries have attracted widespread attention due to their high energy density and environmental friendliness. However, problems such as the activation of CO 2 and the decomposition of discharge products (Li 2 CO 3 and C) are the key to restrict its development. Herein, an amine-based o-phenylenediamine (OPD) as a bifunctional liquid catalyst is introduced into Li-CO 2 battery, which realizes a great improvement of electrochemical performances by optimizing CO 2 reduction and evolution reaction process. Experiments coupled with theoretical calculations verify that the introduced OPD accelerates the migration of the discharge intermediates and makes the discharge products grow through the solution phase pathway, which greatly eliminates the passivation of the cathode as well as releases the battery capacity. Moreover, OPD, as a liquid redox mediator, can effectively promote the decomposition of discharge products, greatly reduce the charging potential and improve round-trip efficiency. Additionally, thanks to the increased activity of CO 2 reduction reaction (CDRR) and CO 2 evolution reaction (CDER) catalyzed by OPD, the cycling performance of Li-CO 2 battery has also been improved. [ABSTRACT FROM AUTHOR]