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• A numerical analysis method for the debris cloud considering macroscopic multi-phase states is established. • we explore the debris cloud phase state partitioning criterion method and the temperature failure criterion is added. • The initial phase distribution diagram is obtained from the inversion of the debris cloud at the steady time. Hypervelocity impacts can cause material phase transitions. Solid-phase fragments retain the material strength and exhibit high penetration performance. Liquid- and gas-phase fragments have a much lower penetration performance but can still generate momentum and thermal impact on the rear plate. This study adopted the finite element-smoothed particle hydrodynamics (FE-SPH) adaptive method to simulate the phase transitions of debris clouds under hypervelocity impacts. The Johnson–Cook and maximum tensile stress failure criteria were used to simulate material compression and tensile failures, respectively. The material liquefaction temperature was considered the threshold of the temperature failure criterion. Three phase-transition criteria are proposed using temperature and pressure methods and a material phase diagram, in which the intermediate phase states are also defined, i.e., the melting-phase of the solid–liquid intermediate state and the hot-liquid phase of the liquid–gas intermediate state. A symmetric plate impact was used to verify the reliability of the physical quantities. The reliability of the numerical results was verified using experimental and numerical phase diagrams of the debris clouds at different velocities. The phase evolution characteristics of the debris clouds under hypervelocity impacts were studied using the FE-SPH adaptive method and temperature phase-transition criteria. The initial projectile phase model was obtained by the inversion of the debris cloud phase distribution at the steady-state moment, laying the foundation for the debris cloud phase model. [ABSTRACT FROM AUTHOR]

Abstract Heavy metal contamination of environmental media in mining area is a global major concern because of its potential threat for human health through food chain. However, the comparison of exposure level and health risk is scarce among people living in the vicinity of mining area with different pollution source. In this study, the concentrations of Mn, Cd, As, Pb, Cu, Zn, Cr and Ni in soil, air, water, rice, vegetable, fish, poultry meat and pork from a Pb-Zn mining area and a Mn mining area in Huayuan county, China were determined by inductively coupled plasma mass spectrometry. Results showed that the environmental media and foodstuffs in the two areas were contaminated by Cd, Pb, Zn, Cu, Cr and Ni. However, the pollution was more serious in Pb-Zn mining area than Mn mining area. The total hazard index (HI) was 6.59 and 4.55 in Pb-Zn mining area and Mn mining area, respectively, indicating a moderate non-carcinogenic risk of local people. As intake via rice ingestion was the predominant contributor to the total HI in the two mining areas, accounting for 25% and 35%, respectively. For Pb-Zn mining area, Cd intake through vegetable consumption and Mn intake via air inhalation appeared to be another two important components contributing to HI. This study highlights the multi-element and multi-pathway exposure assessment to evaluate the potential health risk and emphasizes concerns to reduce As and Cd in agricultural products as well as Mn in air to decrease the detrimental health effects of local resident. Highlights • Heavy metal pollution was more serious in Pb-Zn mining area than Mn mining area. • Heavy metal pollution posed a moderate non-carcinogenic risk to local people. • Health risks in the two mining areas were mainly attributed to As via rice ingestion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ti 3 C 2 /Pd was designed for efficient catalytic transfer hydrogenation of nitrobenzene. • Experimental and DFT theoretical studies unravel unique catalytic mechanism. • Electron transfer at Ti 3 C 2 /Pd interfaces changes Pd electron configure (4 d 10 → 4 d 10-x). • Electron-deficient Pd boosts formic acid dissociation for atomic H* production. • Ti 3 C 2 /Pd chemisorbs active H* and inhibits undesirable H 2 evolution. Catalytic transfer hydrogenation (CTH) with formic acid attracts much interest in catalysis, but the sluggish H* production and undesirable H 2 evolution reaction (HER) limit its practical applications. Herein we anchored Pd nanoparticles (NPs) on layered Ti 3 C 2 MXene for efficient and selective CTH of nitrobenzene in the presence of formic acid. Some electrons in Pd NPs transferred to Ti 3 C 2 MXene upon formation of Ti 3 C 2 /Pd nanohybrids, as confirmed by XPS and DFT simulations. The electron transfer changed Pd valance electron configuration from 4 d 10 to 4 d 10-x. Such electron-deficient Pd NPs tuned reaction pathway and promoted formic acid dissociation, both of which favored the production of active H* atoms, i.e., the exact reductant for CTH. Compared with Pd NPs, Ti 3 C 2 /Pd showed stronger adsorption of H* and therefore inhibited the occurrence of HER (2H*→H 2). Owing to favorable H* production and HER inhibition, Ti 3 C 2 /Pd (15 wt% Pd) showed enhanced nitrobenzene CTH performance with turnover frequency of 351.7 h−1 and 99% aniline selectivity, outperforming most of current catalysts. Our work might inspire designing more advanced CTH catalysts by tuning their valance electron configurations with 2D MXene materials. [ABSTRACT FROM AUTHOR]

Abstract: The liquid adsorption behavior and surface properties of α-, β-, and γ-cyclodextrin, CD, were studied and compared by FTIR and capillary rise method. These three CDs all showed an intense peak at 1155cm−1 due to the C–O structure stretching and the peak height was found to reduce with the sugar ring molecules of CD increase. All these three CDs adsorbed the non-polar liquids greatly as compared with the polar liquid due to their total surface free energies dominated by the Lifshitz–van der Waals interactions component. The increase of the sugar ring molecules has been found to increase the Lewis acid–base property of CDs. [Copyright &y& Elsevier]

The excitations of ligand-to-metal charge transfer in the UV–vis spectra of the complexes Cp2MCl2 (Cp=π-C5H5, M=Ti, Zr, Hf) were described with the time-dependent density functional theory and the differential self-consistent-field density functional theory (ΔSCF–DFT). The nature of the main spectral features was interpreted on the basis of the electronic structure of the complexes. The optimization of the molecular structure for Cp2MCl2 yielded consistent pseudotetrahedral geometries. With the transition from ground state to excited state, the electrons transferred from Cp ligands to the central metals M, accompanied by an increase in the binding length of M&z.sbnd;Cl. This transfer process accounted for the first two absorption bands observed experimentally. The energies and oscillator strengths for the low-lying excitations depended strongly on the nature of the central metals. With varying the central metals from Ti, Zr, and to Hf, the energy gap increased between the sets of highest occupied molecular orbitals (HOMOs) and the sets of lowest unoccupied molecular orbitals (LUMOs). This increase was originated from an increment of energy for the LUMO sets that are mainly of d orbital of the metal and a relatively stable energy level of the HOMO sets that are mainly of p-orbital of Cp and Cl ligands. The excitation energies calculated by these methods showed a small difference, which can be well understood by a relativistic effect. The predicted level patterns of the lowest triplet excited states fit well the available phosphorescence data. [Copyright &y& Elsevier]

No-Reference Image Quality Assessment (NR-IQA) is a fundamental and important task in the field of computer vision. Most NR-IQA methods have limitation in making desirable NR-IQA performance due to the lack of sufficiently rich features. To address this problem, we propose a dual-attention pyramid Transformer network for NR-IQA. In the proposed method, a feature extraction module is firstly used to extract multi-scale features which contain rich distortion and semantic information. Then, a pyramid Transformer network with channel and spatial attentions is designed to learn multi-scale global features from spatial and channel aspects. The combination of pyramid structure and dual attentions enables our network to focus on features in different regions of the image and learn richer and more comprehensive global features. This in turn improves the quality score prediction performance. Finally, the score prediction module predicts the quality scores in different stages of the pyramid Transformer network by channel adaptive prediction branches and determines the final quality score by aggregating these quality scores. Extensive experiments performed on four widely used public databases show that our proposed method is superior to some state-of-the-art NR-IQA methods in perceiving image quality. • We design a new Dual-attention Block. • We design a novel MSIC-patch embedding block. • We propose a Dual-attention Pyramid Transformer Network for NR-IQA. • The proposed method is superior to some state-of-the-art NR-IQA methods. [ABSTRACT FROM AUTHOR]

Highlights: [•] A regenerative braking system is designed for a rear-driven electric minivan. [•] A new control strategy coordinating energy efficiency and braking feel is proposed. [•] The control strategy is verified by simulation and hardware-in-loop (HIL) tests. [•] The proposed control strategy offers higher regeneration efficiency. [Copyright &y& Elsevier]

• The advanced space debris protection shields in terms of both structural and material improvements are reviewed, and further directions for improvement are proposed. • The characterization for debris clouds and the phase transition of debris clouds are reviewed. • The lack of theoretical models characterizing irregular debris clouds for high impact/attack angles or complex shields is highlighted. • The numerical simulation methods for debris clouds are reviewed, one of the frontier directions proposed is the FE-SPH adaptive method. Spacecraft employ space debris protection shields to mitigate the threat of hypervelocity impact (HVI) from millimeter-sized (envisioned in centimeters) hazardous space debris. Advancements in protection shields have primarily leveraged high-performance materials, such as high-performance fiber composites, multifunctional impedance gradient materials, and metallic honeycombs and foams, to enhance their protective capabilities. This paper provides a comprehensive overview of advanced space debris protection shields for HVI, covering the design and optimization of protective materials or structures, properties of debris clouds, phase transition issues of debris clouds, and numerical simulation techniques. Finally, to address the current research deficiencies considering the latest practical developments in space debris protection engineering, it is essential to propose engineering science research. These are important for enhancing the safety, stability, and longevity of spacecraft. [ABSTRACT FROM AUTHOR]

This study systematically assessed the feasibility of replacing ordinary Portland cement (OPC) with a multi–solid waste cementitious material (MSC) composed of ground granulated blast furnace slag (GGBS), steel slag (SS), red mud (RM), fly ash (FA), limestone powder (LP), and desulfurized gypsum (DG) in specific proportions of 28%, 25%, 21%, 11.5%, 9%, and 5.5%, respectively. The hydration characteristics were analyzed using hydration heat, XRD, TG–DTG, FTIR, and SEM–EDX tests. The heavy metal content and leaching concentration of the MSC were determined using inductively coupled plasma mass spectrometry (ICP–MS). The unconfined compressive strength (UCS), indirect tensile strength (ITS), and water stability of the MSC-stabilized clayey sand and stone chips were investigated. The results showed that synergistic hydration among multiple solid wastes generated abundant hydration products, including Ca(OH) 2 , C–(A)–S–H gels, and AFt crystals, which formed dense and compact microstructures. Furthermore, Pb and Cd in the raw material were effectively solidified by MSC hydration, with leaching concentrations as low as 0.181 and 0.002 mg/L, respectively. The contents and leaching concentrations of the other heavy metals were significantly lower than their limits. The pH of the MSC mortar leachate was stable at 11.56 with curing age, which complied with environmental safety standards. Moreover, MSC as a binder demonstrated higher UCS, ITS, and water stability in comparison to OPC. When MSC was added at a 6% dosage to stabilize clayey sand and stone chips, the UCS values measured after 7 days of curing were 2.82 MPa and 4.83 MPa, respectively. Finally, the MSC was successfully applied in practical projects, demonstrating its promising application prospects. • The synergistic hydration characteristics of a multi–solid waste cementitious material (MSC) were revealed. • The environmental impact of MSC was investigated. • The mechanical properties of MSC-stabilized materials were evaluated. [ABSTRACT FROM AUTHOR]

Over decades many studies have focused on the biodegradation of microcystins (MCs), and some Mlr-dependent MC-degrading bacteria were recorded, but the ecological functions, metabolic traits, and potential evolution of these organisms remain poorly understood. In this study, 16S rRNA-based phylogeny unraveled a wide range of genetic diversity across bacterial lineage, accompanied by re-evaluation of taxonomic placement of some MC-degrading species. Genome-wide comparison showed that considerable genes unique in individual organisms were identified, suggesting genetic differentiation among these Mlr-dependent MC-degrading bacteria. Notably, analyses of metabolic profiles first revealed the presence of functional genes involved in phenylacetate biodegradation in the specialized genomic regions, and mlr gene cluster was located around the neighborhood. The identification of transposable elements further indicated that these genomic regions might undergo horizontal gene transfer events to recruit novel functionalities, suggesting an adaptive force driving genome evolution of these organisms. In short, phylogenetic and genetic content analyses of Mlr-dependent MC-degraders shed light on their metabolic potential, ecological roles, and bacterial evolution, and expand the understanding of ecological status of MCs biodegradation. Unlabelled Image • 16S rRNA-based phylogeny re-evaluating the taxonomy of MC-degrading bacteria • Genome-wide study strongly suggesting the genetic differences as to gene repertoire • Study on metabolic profiles revealing the presence of phenylacetate-related genes • Evolutionary analysis indicating the potential recruitment of functional genes • Schematic model for ecological roles of Mlr-dependent MC-degrading bacteria [ABSTRACT FROM AUTHOR]

Diverse metabolic behaviors endow microorganisms with various ecological functions, and metabolic activities of microbial species may affect the environmental conditions of their habitats. In this study, genome-guided analysis of Planktothrix spp. first divided these strains into six distinct groups, and comparisons of Planktothrix genomes revealed the inter- and intra-species variation. Prediction of central metabolism showed the functional diversity with regard to uptake of carbon, nitrogen, and sulfur sources. As the carbon-fixing microorganisms, Planktothrix isolates played a critical role in transforming the atmospheric carbon into organic carbon-the waterbodies' pool of available carbon. Diazotrophic lifestyle in certain Planktothrix strains may provide valuable avenues for supporting the equilibrium community. Furthermore, genome mining supported the exploration of biosynthetic gene clusters dedicated to cyanobacterial natural products, mainly including non-ribosomal peptide, polyketide, cyanobactin, and microviridin. Notably, some Planktothrix strains had the potential to non-ribosomally synthesize the microcystin (MC), a potent cyclic heptapeptide toxin, and MC-mediated cycling might strengthen the association between MC-producing and MC-degrading microorganisms. In short, genome-wide study of Planktothrix strains advances our current understanding of their metabolic potential and especially ecological roles in shaping natural environments. Unlabelled Image • Genome-based phylogeny dividing Planktothrix strains used into six separate clades • A global comparison strongly showing the intra- and inter-species differentiation • Metabolic diversity potentially contributing to their various ecological roles • An interplay pattern probably suggesting nutrient recycling in aquatic environments [ABSTRACT FROM AUTHOR]

Abstract Ethnopharmacological relevance Herpetospermum caudigerum Wall. (HCW) is a traditional Tibetan medicine, which has been used to ameliorate liver injuries in the folk. Aim of the study Liver fibrosis has been recognized as a major lesion of the liver that leads to liver cirrhosis/hepatocarcinoma and even to death in the end. This study aims to demonstrate the protective effect of HCW against CCl 4 -induced liver injury in rats and to explore the underlying mechanisms. Materials and methods Hepatic fibrosis was induced by intraperitoneal injection of CCl 4. Liver function markers, fibrosis markers, serum anti-oxidation enzymes as well as elements levels were determined. Serum and liver tissues were subjected to NMR-based metabolomics and multivariate statistical analysis. Results HCW could significantly reduce the elevated levels of fibrosis markers such as hyaluronidase, laminin, Type III procollagen and Type IV collagen in the serum, improve the activities of the antioxidant enzymes, and effectively reverse the abnormal levels of elements in liver fibrosis rats. Correlation network analysis revealed that HCW could treat liver fibrosis by ameliorating oxidative stress, repairing the impaired energy metabolisms and reversing the disturbed amino acids and nucleic acids metabolisms. Conclusion This integrated metabolomics approach confirmed the validity of the traditional use of HCW in the treatment of liber fibrosis, providing new insights into the underlying mechanisms. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Background Pneumonia is a common early-childhood respiratory infection that leads to long-term health impacts, but its risk factors remain unclear. Objective To examine the association between early life exposure to both outdoor and indoor air pollution and childhood pneumonia. Methods We conducted a retrospective cohort study of 2598 children aged 3–6 years in Changsha, China (2011-2012). Children's life-time prevalence of pneumonia and exposure to indoor air pollution related to home renovation were surveyed by a questionnaire answered by the parents. Children's exposure to outdoor air pollution, including nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ), and particulate matter with an aerodynamic diameter ≤ 10 μm (PM 10 ), was estimated using the measured concentrations at monitoring stations. Association between childhood pneumonia and exposure to indoor and outdoor air pollution during both prenatal and postnatal periods were examined by using logistic regression model in terms of odds ratio (OR) and 95% confidence interval (CI). Results Life-time prevalence of pneumonia in preschool children in Changsha is high, up to 38.6%.We found that childhood pneumonia was associated with postnatal exposure to outdoor particulate air pollutant PM 10 , adjusted OR (95% CI) = 1.26 (1.00–1.57) for per 6 μg/m 3 increase in the concentration. Pneumonia was also associated with postnatal exposure to indoor renovation, adjusted OR (95% CI) = 1.30 (1.02–1.64) for new furniture and 1.30 (1.00–1.69) for redecoration. Combined exposure to outdoor high PM 10 and indoor renovation significantly increased the pneumonia risk. Sensitivity analysis indicated that the association was heterogeneous in different subgroups, but stronger in male and younger children. Conclusion High prevalence of childhood pneumonia in China may be associated with postnatal exposure to ambient particulate air pollution and house renovation. [ABSTRACT FROM AUTHOR]

Background Otitis media (OM) is a common infection in early childhood with repeated attacks that lead to long-term complications and sequelae, but its etiology still remains unclear. Objective To examine the association between early life exposure to air pollution and childhood OM, with the purpose of identifying critical windows of exposure and key components of air pollution in the development of OM. Methods We conducted a prospective cohort study of 1617 children aged 3–4 years in Changsha, China (2011–2012). The prevalence of OM was assessed by a questionnaire administered by the parents. Individual exposures to nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ) and particulate matter with an aerodynamic diameter ≤ 10 μm (PM 10 ) during prenatal, postnatal, and current windows were estimated using the measured concentrations at monitoring stations. We used logistic regression model to examine the OM risk in terms of odds ratio (OR) and 95% confidence interval (CI) for exposure to different air pollutants during different timing windows, adjusting for covariates, multi-pollutants, and multi-windows. Results Life-time prevalence of doctor-diagnosed OM in preschool children in Changsha was 7.3%. Childhood OM was associated only with prenatal exposure to the industrial air pollution with adjusted OR (95% CI) = 1.44 (1.09–1.88) for a 27 μg/m3 increase in SO 2 , particularly during the first trimester of pregnancy. We further found that prenatal SO 2 exposure was not associated with the repeated attacks but was associated with the onset of OM, adjusted OR (95% CI) = 1.47 (1.10–1.96). The association between prenatal SO 2 exposure and early childhood OM was robust after adjusting for other pollutants and windows. Sensitivity analysis indicated that the association was stronger in females, children with parental atopy, and children living in houses with cockroaches, new redecoration, and condensation on window pane during winter. Conclusion We provide new evidence that prenatal exposure to industrial air pollution is associated with early childhood OM in China and may contribute to the onset of childhood OM. Our findings are helpful in developing more effective preventative strategies for childhood OM. [ABSTRACT FROM AUTHOR]

A biotransformation method of producing resveratrol with immobilized Aspergillus oryzae negative pressure cavitation bioreactor (ICNPCB) with biphasic ionic liquid aqueous system pretreatment was investigated. Subsequently, the biotransformation conditions were optimized for the resveratrol production under types of ILs [C4MIM]Br, concentration of ILs 0.75 M, temperature 31 °C, ratios of solid to liquid 1:15 (mg/L), time 60 h and pH 6.0, the yield of resveratrol reached 224.61 ± 0.35 µg/g, which increased 4.36-fold to that of untreated one. The conversion rate of piceid reached 85.21%. The residual activity of immobilized microorganism was 82.26% after used for 15 runs. The developed method could be an effectively alternative biotransformation method for producing resveratrol from the waste residue of wine. [ABSTRACT FROM AUTHOR]

Background Environmental factors have been found to be associated with allergic diseases, but it is unclear which environmental factor during which exposure window causes what kind of allergic diseases. Objectives We investigated association between exposure to some predominant outdoor and indoor environmental factors during preconceptional, prenatal, and postnatal periods and allergic diseases/symptoms in 2598 children in China. Methods Children's lifetime incidence of allergic diseases and current prevalence of allergic symptoms and exposure to indoor new furniture/redecoration and mold/dampness was surveyed by a questionnaire. Exposure to outdoor air pollutants was estimated by the concentrations measured at air quality monitoring stations. Multiple logistic regression model was used to evaluate the associations between outdoor air pollutants and indoor environmental factors and allergic diseases (asthma, allergic rhinitis, and eczema) and symptoms (wheezing, night cough, and rhinitis-like). Results We found that preconceptional, prenatal, and postnatal exposure to outdoor industrial and traffic air pollutants were significantly associated with increase in the risk of childhood asthma, and also positively associated with allergic rhinitis and eczema. However, we cannot distinguish the effect of outdoor air pollutants and exposure windows because of their high correlations. New furniture was associated with eczema and allergic rhinitis during postnatal exposure, but redecoration associated with asthma and eczema during prenatal exposure. Indoor visible mold/damp stains was significant for eczema during prenatal exposure and asthma during postnatal exposure respectively, but window condensation was significant for all childhood allergic diseases during both prenatal and postnatal exposures. Allergic symptoms in children were found to be associated with exposure to indoor factors only. Conclusions Associations between outdoor air pollutants and indoor environmental factors and childhood allergic diseases/symptoms were divergent and related to the timing of exposure. [ABSTRACT FROM AUTHOR]

Abstract: Several important monolignols such as coniferyl alcohol were catalyzed using Rhus laccase (RL) from Rhus vernicifera in a water/acetone solution. The enzymatic mechanism is discussed in detail. Sites 6, β, and phenolic oxygen were the main active sites of phenylpropanoid compounds, which were first oxidized by the enzyme and then radicalized. RL was also responsible for lignin biosynthesis, especially in the early stage. [Copyright &y& Elsevier]

Low birth weight (LBW) remains a major public health problem worldwide, yet its crucial environmental risk factors are still unclear. To examine the association between LBW (term and preterm LBW) and prenatal exposure to ambient air pollution and home environmental factors as well as their combination, in order to identify critical time window for exposure and key outdoor and indoor factors in LBW development. A cohort study of 3509 preschool children was performed in Changsha, China during the period 2011–2012. A questionnaire was conducted to survey each child's birth outcome and each mother's exposure to home environmental factors including parental smoking, new furniture, redecoration, mold/damp stains, window pane condensation, and household pets during pregnancy. Maternal exposure to inhalable particulate matter (PM 10), industrial air pollutant (SO 2), and traffic air pollutant (NO 2) was estimated during different time windows of gestation, including conception month, three trimesters, birth month, and whole gestation. Associations of term and preterm LBW with ambient air pollutants and home environmental factors were assessed by multiple logistic regression models in terms of odds ratio (OR) with 95% confidence interval (CI). Term LBW (TLBW) was significantly associated with exposure to ambient PM 10 during pregnancy, with OR (95% CI) = 1.47 (1.00–2.14) for per IQR increase after adjustment for the covariates and home environmental factors. Specifically, we identified the significant association in early phase of pregnancy including conception month (1.90, 1.09–3.30) and the first trimester (1.72, 1.10–2.69). We further found that TLBW was significantly related with parental smoking at home, OR (95% CI) = 2.17 (1.09–4.33). However, no association was observed for preterm LBW (PLBW). The TLBW risk of ambient air pollution and home environmental factors was independent each other and hence the combined exposure to ambient PM 10 and indoor parental smoking caused the highest risk. Sensitivity analysis suggested that foetus with younger mothers were significantly more susceptible to risk of indoor parental smoking, while those with smaller house and cockroaches were more sensitive to risk of outdoor PM 10 exposure. Prenatal exposure to combined outdoor and indoor air pollution, particularly in critical window(s) during early pregnancy, significantly increases the risk of term LBW. • Air pollution was associated with term low birth weight (LBW) but not with preterm LBW. • We found term LBW was associated with prenatal exposure to ambient inhalable particle (PM 10). • Term LBW was also related with parental smoking at home during pregnancy. • Exposure to combined outdoor and indoor air pollution posed the highest risk of term LBW. • Early pregnancy was identified as the most critical time window for exposure susceptibility. [ABSTRACT FROM AUTHOR]