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Transition metal doping is an ideal strategy to construct multifunctional and efficient nanozymes for biosensing. In this work, a metal-doped CoMnOx nanozyme was designed and synthesized by hydrothermal reaction and high-temperature calcination. Based on its oxidase activity, an "on-off-on" smartphone sensing platform was established to detect ziram and Cu2+. The obtained flower-shaped CoMnOx could exhibit oxidase-, catalase-, and laccase-like activities. The oxidase activity mechanism of CoMnOx was deeply explored. O2 molecules adsorbed on the surface of CoMnOx were activated to produce a large amount of O2·-, and then, O2·- could extract acidic hydrogen from TMB to produce blue oxTMB. Meanwhile, TMB was oxidized directly to the blue product oxTMB via the high redox ability of Co species. According to the excellent oxidase-like activity of CoMnOx, a versatile colorimetric detection platform for ziram and Cu2+ was successfully constructed. The linear detection ranges for ziram and Cu2+ were 5~280 μM and 80~360 μM, and the detection limits were 1.475 μM and 3.906 μM, respectively. In addition, a portable smartphone platform for ziram and Cu2+ sensing was established for instant analysis, showing great application promise in the detection of real samples including environmental soil and water. [ABSTRACT FROM AUTHOR]

To address China's small coal power units facing shutdown and retirement, which urgently need life cycle extension and renovation, a complete solar thermal storage simulation power generation system based on the original site of a decommissioned thermal power unit is developed using Ebsilon software in this study. The operational characteristics of the simulated system are studied in depth to build a system with integrity and stability that can carry out economic and stable power production. The results of simulation tests on the solar collector system and the thermal storage subsystem show that the energy storage rate of the energy storage subsystem is affected by light intensity and significantly increases at approximately 8:00 a.m. The annual power generation capacity of the system is influenced by the energy storage hours set by the energy storage subsystem, and the annual power generation capacity increases more significantly when the energy storage hours are controlled within the range of 5–8 h. The operating efficiency of the corresponding subsystem can be improved by selecting a suitable location for the light intensity required and controlling the effective reflectivity of the mirror field and the energy storage hours, which can ensure the system's stable operation. The research results provide theoretical guidance for reusing and transforming retired thermal power units. [ABSTRACT FROM AUTHOR]

To apply AquaCrop to the study of agricultural soil moisture in the North China Plain, a water-treatment experiment on summer maize was carried out at the Fengqiu experimental station of the Chinese Academy of Sciences from 2017 to 2018. A water treatment was used to achieve field water capacities of 20 (W1), 40 (W2), and 60 (W3) cm soil layers under irrigation, and a rain-fed treatment (W0) was added. The model parameters were calibrated using the measured data in 2017. Then, they were applied to 2018 to verify the ability of the model to simulate water stress. The results showed that the variation trends for crop yield, canopy coverage, total soil water content, and the curve in the growth cycle simulated via AquaCrop were consistent with the actual observations; the results of a discrete analysis showed that the values of b (regression coefficient), R2 (determination coefficient), and EF (efficiency) were close to 1, and the values of the RMSE (root mean square error) were close to 0, which proved that the model could simulate dynamic changes in summer maize yield, canopy coverage, and total soil water content well. AquaCrop had good applicability in the North China Plain and could be applied to the study of agricultural water consumption and water-use efficiency in this area. The simulated values obtained can serve as an easily obtainable source of long-term experimental data in areas with frequent non-extreme weather events. [ABSTRACT FROM AUTHOR]

Wood–plastic composites (WPCs) have received growing attention due to their good water resistance, environmental friendliness, and recyclability. For the application of WPCs in interior decoration and other high–value fields, it is necessary to preserve these characteristics whilst enhancing their mechanical properties and surface aesthetics. In this study, we used a sandwich structure and four interface modifiers to prepare wood veneer/wood flour–polyvinyl chloride composites (WWPVCs). The results revealed that the WWPVCs treated with a silane coupling agent exhibited superior interfacial bonding and mechanical properties compared to those obtained using other interface modifiers. The interfacial bonding strength of the treated sample reached 1.22 MPa, which was 122% higher than that of the untreated sample. In addition, the wood failure ratio of the optimal sample reached 80%. Furthermore, the dipping–peeling length was found to be shorter than those achieved using other interface modifiers after tests at 63 and 100 °C, indicating that the material treated using the silane coupling agent exhibits an excellent resistance to moisture and heat. Notably, silane coupling agents are easily prepared as solvent–based modifiers, and they do not release harmful gases (e.g., formaldehyde), thereby rendering them highly effective in the preparation of environmentally friendly WPC products. [ABSTRACT FROM AUTHOR]

The flat peach is a high economic value table fruit possessing excellent quality and a unique aroma. This article investigated the quality characteristics and aroma fingerprinting of flat peaches (Qingpan, QP; Ruipan 2, R2; Ruipan 4, R4; Wanpan, WP) from Xinjiang in terms of taste, antioxidant capacity, and volatile aroma compounds using high-performance liquid chromatography (HPLC) and HS-SPME-GC-MS. The results showed that the flat peaches had a good taste and high antioxidant capacity, mainly due to the high sugar–low acid property and high levels of phenolic compounds. This study found that sucrose (63.86~73.86%) was the main sugar, and malic acid (5.93~14.96%) and quinic acid (5.25~15.01%) were the main organic acids. Furthermore, chlorogenic acid (main phenolic compound), epicatechin, rutin, catechin, proanthocyanidin B1, and neochlorogenic acid were positively related to the antioxidant activity of flat peaches. All flat peaches had similar aroma characteristics and were rich in aromatic content. Aldehydes (especially benzaldehyde and 2-hexenal) and esters were the main volatile compounds. The aroma fingerprinting of flat peaches consisted of hexanal, 2-hexenal, nonanal, decanal, benzaldehyde, 2,4-decadienal, dihydro-β-ionone, 6-pentylpyran-2-one, 2-hexenyl acetate, ethyl caprylate, γ-decalactone, and theaspirane, with a "peach-like", "fruit", and "coconut-like" aroma. Among them, 2,4-decadienal, 2-hexenyl acetate, and theaspirane were the characteristic aroma compounds of flat peaches. The results provide a theoretical basis for the industrial application of the special aroma of flat peaches. [ABSTRACT FROM AUTHOR]

The vegetation–temperature relationship is crucial in understanding land–atmosphere interactions on the Tibetan Plateau. Although many studies have investigated the connections between vegetation and climate variables in this region using remote sensing technology, there remain notable gaps in our understanding of vegetation–temperature interactions over different timescales. Here, we combined site-level air temperature observations, information from the global inventory modeling and mapping studies (GIMMS) dataset, and moderate-resolution imaging spectroradiometer (MODIS) products to analyze the spatial and temporal patterns of air temperature, vegetation, and land surface temperature (LST) on the Tibetan Plateau at annual and seasonal scales. We achieved these spatiotemporal patterns by using Sen's slope, sequential Mann–Kendall tests, and partial correlation analysis. The timescale differences of vegetation-induced LST were subsequently discussed. Our results demonstrate that a breakpoint of air temperature change occurred on the Tibetan Plateau during 1994–1998, dividing the study period (1982–2013) into two phases. A more significant greening response of NDVI occurred in the spring and autumn with earlier breakpoints and a more sensitive NDVI response occurred in recent warming phase. Both MODIS and GIMMS data showed a common increase in the normalized difference vegetation index (NDVI) on the Tibetan Plateau for all timescales, while the former had a larger greening area since 2000. The most prominent trends in NDVI and LST were identified in spring and autumn, respectively, and the largest areas of significant variation in NDVI and LST mostly occurred in winter and autumn, respectively. The partial correlation analysis revealed a significant negative impact of NDVI on LST during the annual scale and autumn, and it had a significant positive impact during spring. Our findings improve the general understanding of vegetation–climate relationships at annual and seasonal scales. [ABSTRACT FROM AUTHOR]

Core–shell composites with strong weather resistance, mechanical strength and creep resistance can be prepared using co-extrusion technology. Considering the weak bonding strength between core–shell interfaces, this study started from the concept of a mortise and tenon combination; three types of conical, rectangular and trapezoidal mortise and tenon joints were prepared, and their bending properties, long-term creep properties, interfacial bonding properties, and dimensional stability properties were tested. Results showed that the mortise and tenon structure could form a mechanical interlock between the outer-shell-layer polyvinyl chloride (PVC) wood–plastic composite (WPVC) and the inner-core-layer laminated veneer lumber (LVL), which could effectively improve the interface bonding property between the two layers. Among them, the trapezoidal mortise and tenon structure had the largest interface bonding force compared with the tapered and rectangular mortise and tenon structure, where the interface bonding strength reached 1.01 MPa. Excellent interface bonding can effectively transfer and disperse stress, so the trapezoidal mortise and tenon structure had the best bending properties and creep resistance, with a bending strength of 59.54 MPa and a bending modulus of 5.56 GPa. In the long-term creep test, the deformation was also the smallest at about 0.2%, and its bending properties, creep resistance and interface bonding performance were also the best. The bending strength was 59.54 MPa and the bending modulus was 5.56 GPa; in the long-term creep test, the strain curve was the lowest, about 0.2%. In addition, the mortise and tenon structure could disperse the stress of the inner shell LVL after water absorption and expansion, thus significantly improving the dimensional stability of the co-extruded composite after water absorption. [ABSTRACT FROM AUTHOR]

Forests are essential for the provision of water, financial resources, food, and carbon, and offer immense ecosystem service values. The accurate, quantitative, and objective evaluation of forest ecosystem service (FES) values can help uncover methods for realizing ecological product value, which in turn supports forest conservation and ecological benefit enhancement. In China, FES valuation methods are diverse and tailored to specific objectives, encompassing matter quantity assessment, value quantity assessment, energy value analysis, and landscape ecological modeling methods. The "Forest Ecosystem Service Function Assessment Specification" guideline plays a crucial role in fostering standardized valuation. Carbon-related ecosystem services have been increasingly studied in China; however, valuation challenges remain, including data accuracy, the double counting of ecosystem services, methodological limitations, and the incomplete assessment of non-use values. Regarding value realization, the development of payment for ecosystem services (PES), ecological product benefit trading (EPBT), ecological premiums, and ecological industries has seen gradual progresses in recent years. However, realization approaches still depend on government support, and the establishment of market-oriented strategies requires further reinforcement. Enhancing FES valuation necessitates the integration of interdisciplinary and multi-method approaches, as well as the creation of an accounting and assessment mechanism. Realization approaches must not only be continuously expanded but also consistently innovated over time. It is essential to consider the impact of market development on FES valuation; establish robust realization approaches; reinforce promotional and guarantee mechanisms; and increase the efficacy of policy management. [ABSTRACT FROM AUTHOR]

miR-144/451 and nuclear factor (erythroid-derived 2)-like 2 (Nrf2) regulate two antioxidative systems that have been identified to maintain redox homeostasis in erythroid cells by removing excess reactive oxygen species (ROS). Whether these two genes coordinate to affect ROS scavenging and the anemic phenotype, or which gene is more important for recovery from acute anemia, has not been explored. To address these questions, we crossed miR-144/451 knockout (KO) and Nrf2 KO mice and examined the phenotype change in the animals as well as the ROS levels in erythroid cells either at baseline or under stress condition. Several discoveries were made in this study. First, Nrf2/miR-144/451 double-KO mice unexpectedly exhibit similar anemic phenotypes as miR-144/451 single-KO mice during stable erythropoiesis, although compound mutations of miR-144/451 and Nrf2 lead to higher ROS levels in erythrocytes than single gene mutations. Second, Nrf2/miR-144/451 double-mutant mice exhibit more dramatic reticulocytosis than miR-144/451 or Nrf2 single-KO mice during days 3 to 7 after inducing acute hemolytic anemia using phenylhydrazine (PHZ), indicating a synergistic effect of miR-144/451 and Nrf2 on PHZ-induced stress erythropoiesis. However, the coordination does not persist during the whole recovery stage of PHZ-induced anemia; instead, Nrf2/miR-144/451 double-KO mice follow a recovery pattern similar to miR-144/451 single-KO mice during the remaining period of erythropoiesis. Third, the complete recovery from PHZ-induced acute anemia in miR-144/451 KO mice takes longer than in Nrf2 KO mice. Our findings demonstrate that complicated crosstalk between miR-144/451 and Nrf2 does exist and the crosstalk of these two antioxidant systems is development-stage-dependent. Our findings also demonstrate that miRNA deficiency could result in a more profound defect of erythropoiesis than dysfunctional transcription factors. [ABSTRACT FROM AUTHOR]

Based on the two-dimensional hydrodynamic model of the finite volume method and structured multigrid, the flow characteristics around a square cylinder with boundary constraint are analysed. The gap ratio G/D (G is the distance from the cylinder to the channel boundary, and D is the side length of the square cylinder) does not change the four flow patterns. Under the laminar vortex street phase, the boundary constraint only reduces the scale of the vortices. The vortex centres are pressed toward the boundaries of the channel, and a low velocity zone is formed near the boundary, but the law of vorticity attenuation along the flow direction is not changed. The flow pattern classification map shows that the boundary constraint increases the Reynolds number required to generate the turbulence flow pattern, and the range of the Reynolds number in the flow pattern of the laminar vortex street has a maximum increase range. The correlation between the time-averaged drag coefficient or the vortex shedding frequency and Reynolds number under different gap ratios indicates that the resistance of the square cylinder and the vortex shedding frequency increase accordingly with the strengthening of the boundary constraint. When G/D < 3.5, the increase is particularly obvious. Meanwhile, the correlation characteristics between the resistance or the vortex shedding frequency of the square cylinder and the Reynolds number are unrelated to the boundary constraint strength. [ABSTRACT FROM AUTHOR]

The addition of abundant fillers to obtain conductive and superhydrophobic waterborne polyurethane (WPU) composites generally results in increased interfaces in the composites, leading to reduced adhesion and poor corrosion resistance. Fillers such as Polytetrafluoroethylene (PTFE) and multi-walled carbon nanotubes (MWCNTs) were first treated by a coupling agent to reduce the contents of the fillers. Thus, in this work, WPU superhydrophobic conductive composites were prepared using electrostatic spraying (EsS). The polar groups (-OH and -COOH, etc.) on the WPU, PTFE, and MWCNTs were reacted with the coupling agent, making the WPU, PTFE, and MWCNTs become crosslinked together. Thus, the uniformity of the coating was improved and its curing interfaces were reduced, causing enhanced corrosion resistance. The dehydration reaction that occurred between the silane coupling agent and the polar surface of Fe formed -NH2 groups, increasing the adhesion of the coating to the steel substrate and then solving the problems of low adhesion, easy delamination, and exfoliation. With the increased content of the modified fillers, the conductivity and hydrophobic property of the composite were amplified, and its corrosion resistance and adhesion were first strengthened and then declined. The composite with the WPU, PTFE, MWCNTs, and KH-550 at a mass ratio of 7:1.5:0.1:0.032 held excellent properties; its volume resistivity and WCA were 1.5 × 104 Ω·cm and 155°, respectively. Compared with the pure WPU coating, its adhesive and anticorrosive properties were both better. This provides a foundation for the fabrication and application of anticorrosive and conductive waterborne composites. [ABSTRACT FROM AUTHOR]

Calcium-dependent protein kinases (CDPK) are implicated in signaling transduction in eukaryotic organisms. It is largely unknown whether StCDPK28 plays a role in the response to water deficiency and osmotic stress in potato plants (Solanum tuberosum L.). Potato cv. Zihuabai was cultivated under natural, moderate, and severe water deficiency conditions; to induce osmotic stress, potato plants were treated with 10% or 20% PEG. StCDPK28-overexpression and StCDPK28-knockdown plants were constructed. StCDPKs were evaluated by qRT-PCR. The subcellular location of the StCDPK28 protein was observed with confocal scanning laser microscopy. Phenotypic changes were indicated by photosynthetic activity, the contents of H2O2, MDA and proline, and the activities of CAT, SOD and POD. Results showed water deficiency and osmotic stress altered StCDPK expression patterns. StCDPK28 exhibited a membrane, cytosolic and nuclear localization. Water deficiency and osmotic stress induced StCDPK28 upregulation. Photosynthetic activity was enhanced by StCDPK28 overexpression, while decreased by StCDPK2 knockdown under water deficiency and osmotic stress. StCDPK28 overexpression decreased H2O2 and MDA, and increased proline, while StCDPK28 knockdown showed reverse results, compared with the wild type, in response to water deficiency and osmotic stress. StCDPK28 overexpression increased the activities of CAT, SOD and POD, while StCDPK28-knockdown plants indicated the reverse trend under water deficiency and osmotic stress conditions. Regulation of StCDPK28 expression could be a promising approach to improve the tolerance ability of potato plants in response to drought or high salt media. [ABSTRACT FROM AUTHOR]

In this work, a novel TiAlMoNbW high-entropy alloy (HEA) film and its corresponding nitrid (HEN) film were deposited on CSS-42L bearing steel by magnetron sputtering technology. The microstructure, microhardness, wear resistance, and corrosion resistance of the coated CSS-42L steel were systematically investigated. With the introduction of nitrogen, the crystal structure of TiAlMoNbW HEA film transformed from BCC into FCC. The microstructure of the deposited film became denser and was accompanied by lower surface roughness. The hardness of the nitride film was further increased from 11.43 to 25.7 GPa due to the formation of saturated metal nitride phases and the solid-solution strengthening of various elements. The tribological results showed that both TiAlMoNbW HEA and HEN films with excellent mechanical properties could improve the wear resistance of CSS-42L substrate, especially for the nitrid film, the mechanical properties of the film are significantly improved, resulting in a substantial reduction in the friction coefficient of about 22% and the wear rate of nearly 79%. In the electrochemical tests, both the TiAlMoNbW HEA and HEN-coated samples exhibited lower current densities and corrosion rates in 3.5 wt.% NaCl and 1 mol/L H2SO4 solutions. It was also noticed that the TiAlMoNbW nitrid film possessed a superior corrosion protection effect for CSS-42L steel. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) are promising candidates for the replacement of lithium-ion batteries (LIBs) because of sodium's abundant reserves and the lower cost of sodium compared to lithium. This is a topic of interest for developing novel anodes with high storage capacity. Owing to their low cost, high stability, and conductivity, carbon-based materials have been studied extensively. However, sp2-C based carbon materials have low-rate capacities. Intensive density functional theory calculations have been implemented to explore the applicability of α, β, and γ graphyne nanotubes (αGyNTs, βGyNTs, and γGyNTs, respectively) as SIB anodes. Results suggest that (3, 0)-αGyNT, (2, 2)-βGyNT, and (4, 0)-γGyNT have, respectively, maximum Na storage capacities of 1535, 1302, and 1001 mAh/g, which exceeds the largest reported value of carbon materials (N-doped graphene foams with 852.6 mAh/g capacity). It was determined that αGyNTs have the largest storage capacity of the three types because they possess the largest specific surface area. Moreover, the larger pores of αGyNTs and βGyNTs allow easier diffusion and penetration of Na atoms compared to those of γGyNTs, which could result in better rate capacity. [ABSTRACT FROM AUTHOR]

Featured Application: Thus far, limited research has been carried out on a large scale that considers landscape characteristics, in-situ soil condition, or land cover. We aim to verify hitherto lacking evidence on the ability of vegetation characteristics and topographical factors to lessen pollutants in tropical regions in China. Soil heavy metals along roadsides pose a great threat to ecosystems while their spatial variations and influencing factors still remain unclear in some regions, especially in tropical areas with complex landscape characteristics. Our study was carried out to determine how the land use, vegetation characteristics, topographical factors and distance to the road affect the soil heavy metal distribution. Taking Jinghong county in Yunnan Province, Southwest China as a case, soil samples were collected at different distances off roads and canonical correspondence analysis (CCA) methods were used to determine the relative importance of different factors. Our results showed that heavy metal sources were obtained mainly from the road, based on the principle component analysis (PCA) identification. There were no obvious trends of soil quality index (SQI) with distance to the road in natural soils, while SQI nutrients and SQI metals in farmlands had a decreasing and increasing trend, respectively, which could both be expressed by logarithm models. However, soil properties showed little differences for road levels while they showed significant differences under land use types. The CCA further showed that heavy metal variations in natural soils were jointly affected by distance, plant coverage, relative elevation and soil properties in decreasing order. [ABSTRACT FROM AUTHOR]

Fabric-based strain sensors can be seamlessly integrated into wearable systems for monitoring various physiological signals. Although many different approaches have been proposed to increase the sensitivity of the fabric-based strain sensor, the linearity and stability in large strains are still challenging. In this paper, a fabric-based strain sensor with good linearity and stability was fabricated via a three-step dip-coating method. Specifically, the combination of multiwall carbon nanotubes and reduced graphene oxide was used as the conductive material to enhance the stability. Meanwhile, microfolded structures between two reduced graphene oxide layers were created via pre-stretching to achieve good linearity. Through mechanical experiments, the performance of the fabric-based strain sensor was characterized. In addition, the practical applications of the strain sensor were demonstrated by monitoring different physiological signals. [ABSTRACT FROM AUTHOR]

A high-performance silicon-carbon nanocomposite facilely prepared by one-step magnetoelectric plasma pyrolysis of the mixture of methane, silane, and hydrogen is proposed for lithium-ion batteries. The ratio of silane, methane, and hydrogen was studied to optimize the properties of the composite. When the ratio of hydrogen/silane/methane is 1:1:3, the composite is composed of spherical Si nanoparticles that uniformly attach to the surface of the tremelliform carbon nanosheets framework, in which the tremelliform carbon nanosheets can effectively resist the volumetric change of the Si nanoparticles during the cycles and serve as electronic channels. The silicon-carbon nanocomposite exhibits a high reversible capacity (1007 mAh g−1 after 50 cycles), a low charge transfer resistance, and an excellent rate performance. In addition, the proposed process for synthesizing silicon-carbon nanocomposite without expensive materials or toxic reagents is an environmentally friendly and cost-effective method for mass production. [ABSTRACT FROM AUTHOR]

Tuning the third-order nonlinear properties of graphene by hybrid method is of great significance in nonlinear optics research. ZrO2/reduced graphene oxide (RGO) composites with different ZrO2 concentrations were prepared by a simple hydrothermal method. The morphology and structure show that ZrO2 nanoparticles were uniformly dispersed on the surface of graphene nanosheets. The nonlinear optical (NLO) characteristics of composites with different ZrO2 concentrations were studied by the Z-scan technique of 532 nm picosecond pulsed laser. The results showed that ZrO2/RGO composites had saturated absorption and positive nonlinear refraction characteristics. Meanwhile, the third-order nonlinear susceptibility of the ZrO2/RGO composite with a 4:1 mass ratio of ZrO2 to graphene oxide could reach 23.23 × 10−12 esu, which increased tenfold compared to RGO, and the nonlinear modulation depth reached 11.22%. Therefore, the NLO characteristics could be effectively adjusted by controlling the concentration of ZrO2, which lays a foundation for further research on the application of ZrO2/RGO composites in NLO devices. [ABSTRACT FROM AUTHOR]

Ozone and PM2.5 (all particulate matter with diameter of 2.5 µm or smaller) are currently two disturbing environmental issues in most cities of China. Black carbon (BC), mainly from incomplete combustion, is one of the most important components of PM2.5 because it can absorb light and contribute to haze pollution and global warming. Meanwhile, volatile organic compounds (VOCs) have become a major air pollutant due to their association with haze, ozone (O3), global warming and human health by direct or indirect processes. In this study, one year-long observation campaign of BC, VOCs and other conventional air pollutants was conducted in the Northern Region of the Hangzhou Bay (NRHB) in Shanghai, China. The results indicated that higher concentration of BC mainly occurred in the autumn and winter, especially in December. In December, higher BC concentrations were found when the air mass came from northwest where there is an important local freeway, or southwest where some adjacent southwest chemical industrial parks are located. Different from the characteristics of BC in urban areas reported by previous studies, the diurnal variation of BC exhibited three peaks, two of which coincided with the morning and evening rush hours which are related to the heavy diesel traffic from a nearby freeway, and the third peak was often found late at night, around 2 am, which might be associated with abnormal emissions from an industrial park or marine traffic in the ocean waterway. BC had weakly negative correlation with O3 and NO, and a strongly positive correlation with PM2.5, SO2, NO2 and NOx, which implies that some incomplete combustion sources might occur in the nearby regions. With regard to VOCs, BC had a strong positive correlation with alkane, alkenes, alkynes, aromatic and non-sulfur VOCs, particularly with aromatic organic matter. Unlike the stronger correlation with aromatics in the morning rush hours, a stronger correlation between BC and alkenes and alkynes during the evening rush hour was observed. The relationships between BC and VOCs, particularly with some specific VOCs species related to the neighboring chemical industrial park, demonstrated that the contribution of the surrounding chemical industrial parks to BC should not be neglected. [ABSTRACT FROM AUTHOR]

The main core of wound treatment is cell growth and anti-infection. To accelerate the proliferation of fibroblasts in the wound and prevent wound infections, various strategies have been tried. It remains a challenge to obtain good cell proliferation and antibacterial effects. Here, human hair kerateine (HHK)/poly(ethylene oxide) (PEO)/poly(vinyl alcohol) (PVA) nanofibers were prepared using cysteine-rich HHK, and then, silver nanoparticles (AgNPs) were in situ anchored in the sulfur-containing amino acid residues of HHK. After the ultrasonic degradation test, HHK/PEO/PVA nanofibrous mats treated with 0.005-M silver nitrate were selected due to their relatively complete structures. It was observed by TEM-EDS that the sulfur-containing amino acids in HHK were the main anchor points of AgNPs. The results of FTIR, XRD and the thermal analysis suggested that the hydrogen bonds between PEO and PVA were broken by HHK and, further, by AgNPs. AgNPs could act as a catalyst to promote the thermal degradation reaction of PVA, PEO and HHK, which was beneficial for silver recycling and medical waste treatment. The antibacterial properties of AgNP-HHK/PEO/PVA nanofibers were examined by the disk diffusion method, and it was observed that they had potential antibacterial capability against Gram-positive bacteria, Gram-negative bacteria and fungi. In addition, HHK in the nanofibrous mats significantly improved the cell proliferation of NIH3T3 cells. These results illustrated that the AgNP-HHK/PEO/PVA nanofibrous mats exhibited excellent antibacterial activity and the ability to promote the proliferation of fibroblasts, reaching our target applications. [ABSTRACT FROM AUTHOR]

Ferro-coke, as a new burden of blast furnace (BF), can not only greatly reduce the energy consumption and CO2 emission, but also promote the resource utilization by using the low-quality iron ore and low-grade coal. However, the strength of ferro-coke decreased with the increasing amount of iron ore powder. In order to maintain the strength of ferro-coke while increasing the amount of iron ore powder, it is necessary to add binder during the coking process to enhance the strength of ferro-coke. In this paper, phenolic resin, silicon metal powder, corn starch, and coal tar pitch were used as binder for the fabrication of ferro-coke. I-type drum machine (I 600), scanning electron microscope (SEM), and X-ray diffraction (XRD) were applied to test the crushing strength, morphology, and microcrystalline structure of the ferro-coke. The results showed that the increasing amount of iron ore powder resulted in lower crushing strength, higher porosity, and the worse macroscopic morphology of ferro-coke. When the amount of iron ore powder reached 40%, obvious cracks appeared on the surface of ferro-coke. When the amount of iron ore was 30%, the crushing strength of ferro-coke dropped to 18.15%. Among the four binders, coal tar pitch could significantly enhance the cold crushing strength of ferro-coke through decreasing the porosity of ferro-coke and improving the bonding effect between carbon matrix particles. In the case of the 10% coal tar pitch addition, the cold crushing strength of ferro-coke was increased from 18.15% to 76.41%; meanwhile, its hot compression strength during gasification improved by 100N. [ABSTRACT FROM AUTHOR]

Deep-sea fungi have become a new arsenal for the discovery of leading compounds. Here five new ophiobolins 1–5, together with six known analogues 6–11, obtained from a deep-sea derived fungus WHU0154. Their structures were determined by analyses of IR, HR-ESI-MS, and NMR spectra, along with experimental and calculated electronic circular dichroism (ECD) analysis. Pharmacological studies showed that compounds 4 and 6 exhibited obvious inhibitory effects on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in murine macrophage RAW264.7 cells. Mechanical study revealed that compound 6 could inhibit the inducible nitric oxide synthase (iNOS) level in LPS-stimulated RAW264.7 cells. In addition, compounds 6, 9, and 10 could significantly inhibit the expression of cyclooxygenase 2 (COX 2) in LPS-induced RAW264.7 cells. Preliminary structure-activity relationship (SAR) analyses revealed that the aldehyde group at C-21 and the α, β-unsaturated ketone functionality at A ring in ophiobolins were vital for their anti-inflammatory effects. Together, the results demonstrated that ophiobolins, especially for compound 6, exhibited strong anti-inflammatory effects and shed light on the discovery of ophiobolins as new anti-inflammatory agents. [ABSTRACT FROM AUTHOR]

The logistics industry around the world has proliferated over recent years as a large number of business organizations have come to recognize the importance of logistics. Cost control used to be emphasized to remain competitive, but recently green logistics has gained attention with the awareness of the integration of economy and society as a whole. Nowadays, green logistics is a useful concept to improve the sustainability of logistics operations, and its related policies and theoretical research have been investigated and explored. However, the practical applications of green logistics are impeded by real-time data sharing, which is common in the logistics industry. Blockchain technology is adopted to address this challenge and enable data sharing among related stakeholders. This paper presents a reference framework for green logistics based on blockchain to reach the sustainable operations of logistics, with the integration of the Internet of Things and big data. Finally, potential benefits and limitations are analyzed when implementing this framework. [ABSTRACT FROM AUTHOR]

Coherent vortex structures (CVS) are discovered for more than half a century, and they are believed to play a significant role in turbulence especially for separated flows. An experimental study is conducted for a pressured backward-facing step flow with Reynolds number (Reh) being 4400 and 9000. A synchronized particle image velocimetry (PIV) system is developed for measurement of a wider range of velocity fields with high resolution. The CVS are proved to exist in the separation-reattachment process. For their temporal evolution, a life cycle is proposed that vortices form in the free shear layer, develop with pairings and divisions and finally shed at the reattachment zone, and sometimes new vortical structures are restructured with recovery of flow pattern. The CVS favor the free shear layer with frequent pairings and divisions particularly at the developing stage around x/h = 2~5 (x: distance from the step in flow direction, h: step height), which may contribute to the high turbulent intensity and shear stress there. A critical distance is believed to exist among CVS, which affects their amalgamation (pairing) and division events. Statistics show that the CVS are well organized in spatial distribution and show specific local features with the flow structures distinguished. The streamwise and vertical diameters (Dx and Dy) and width to height ratio (Dx/Dy) all obey to the lognormal distribution. With increase of Reh from 4400 to 9000, Dx decreases and Dy increases, but the mean diameter (D=0.5 × (Dx + Dy)) keeps around (0.28~0.29) h. As the increase of Reh, the vortical shape change toward a uniform condition, which may be contributed by enhancement of the shear intensity. [ABSTRACT FROM AUTHOR]

Waterborne polyurethane (WPU) coatings hold advantages of good toughness, low cost and environmental protection. However, the low water contact angle (WCA), poor wear and corrosion resistance make them unsuitable for application in the superhydrophobic coatings such as antipollution flashover coatings for transmission lines, self-cleaning coatings for outdoor equipment and waterproof textiles. A series of superhydrophobic WPU composites (SHWPUCs) with micro-rough surface structure was prepared by electrostatic spraying nano-SiO2 particles on WPU composites with low surface energy. It showed that as the hydrophobic system content rose the WCAs of the composites first increased and then remained stationary; however, the adhesion and corrosion resistance first increased and then decreased. An appropriate addition of the hydrophobic system content would lead to a dense coating structure, but an excessive addition could increase the interfaces in the coating and then reduce the coating performance. When the mass ratio of the WPU dispersion, polytetrafluoroethylene (PTFE) particles and modified polydimethylsiloxane was 8:0.3:0.4, 10 g/m2 nano-SiO2 particles were sprayed on the uncured coating surface to construct the SHWPUC with a WCA of 156°. Compared with pure WPU coating, its adhesion and corrosion resistance increased by 12.5% and one order of magnitude, respectively; its wear rate decreased by 88.8%. [ABSTRACT FROM AUTHOR]

The construction of hydropower stations is not without controversy as they have a certain degree of impact on the ecological environment. Moreover, the water footprint and its cumulative effects on the environment (The relationship between the degree of hydropower development and utilization in the basin and the environment) of the development and utilization of cascade hydropower stations are incompletely understood. In this paper, we calculate the evaporated water footprint (EWF, water evaporated from reservoirs) and the product water footprint of hydropower stations (PWF, water consumption per unit of electricity production), and the blue water scarcity (BWS, the ratio of the total blue water footprint to blue water availability) based on data from 19 selected hydropower stations in the Yalong River Basin, China. Results show that: (a) the EWFs in established, ongoing, proposed, and planning phases of 19 hydropower stations are 243, 123, 59, and 42 Mm3, respectively; (b) the PWF of 19 hydropower stations varies between 0.01 and 4.49 m3GJ−1, and the average PWF is 1.20 m3GJ−1. These values are quite small when compared with hydropower stations in other basins in the world, and the difference in PWF among different hydropower stations is mainly derived from energy efficiency factor; (c) all the BWS in the Yalong River Basin are below 100% (low blue water scarcity), in which the total blue water footprint is less than 20% of the natural flow, and environmental flow requirements are met. From the perspective of the water footprint method, the cumulative environmental effects of hydropower development and utilization in the Yalong River Basin will not affect the local environmental flow requirements. [ABSTRACT FROM AUTHOR]

Electrostatic spraying (ES) was used to prepare multi-walled carbon nanotube (MWCNT)/waterborne polyurethane (WPU) abrasion-proof, conductive coatings to improve the electrical conductivity and mechanical properties of WPU coatings. The dispersity of MWCNTs and the electrical conductivity, surface hardness, and wear resistance of the coating prepared by ES (ESC) were investigated. The ESC was further compared with coatings prepared by brushing (BrC). The results provide a theoretical basis for the preparation and application of conductive WPU coatings with excellent wear resistance. The dispersity of MWCNTs and the surface hardness and wear resistance of ESC were obviously better than those of BrC. With an increase in the MWCNT content, the surface hardness of both ESC and BrC went up. As the MWCNT content increased, the wear resistance of ESC first increased and then decreased, while the wear resistance of BrC decreased. It was evident that ESC with 0.3 wt% MWCNT was fully capable of conducting electricity, but BrC with 0.3 wt% MWCNT failed to conduct electricity. The best wear resistance was achieved for ESC with 0.3 wt% MWCNT. Its wear rate (1.18 × 10−10 cm3/mm N) and friction coefficient (0.28) were the lowest, which were 50.21% and 20.00% lower, respectively, than those of pure WPU ESC. [ABSTRACT FROM AUTHOR]

A simple, novel approach is proposed for the preparation of plasma-exfoliated graphene (PEGN) by reducing graphene oxide (GO) through a dielectric-barrier discharge (DBD) plasma treatment in a H2 atmosphere. The surface chemistry, microstructures, and crystallinity of the prepared samples were characterized via X-ray photoelectron spectroscopy, transmission electron microscopy, and Raman spectrometry to determine the formation mechanism of the PEGN. The results demonstrated that the prepared PEGN had only a few layers in its structure and that most of the functional groups containing oxygen on the GO surface were removed. The PEGN exhibited a considerably higher capacity, better cycling stability, and favorable electron transfer rate for use as a cathode material for lithium-ion batteries. This proposed approach is fast, convenient, and inexpensive, constituting a novel means of producing graphene. [ABSTRACT FROM AUTHOR]

Dityrosine is the product of oxidation that has been linked to a number of serious pathological conditions. Evidence indicates that high amounts of dityrosine exist in oxidized milk powders and some milk related foodstuffs, further reducing the nutritional value of oxidized proteins. Therefore, we hypothesize that some receptors related to special diseases would be targets for dityrosine. However, the mechanisms of the interaction of dityrosine with probable targets are still unknown. In the present work, an inverse virtual screening approach was performed to screen possible novel targets for dityrosine. Molecular docking studies were performed on a panel of targets extracted from the potential drug target database (PDTD) to optimize and validate the screening results. Firstly, two different conformations cis- and trans- were found for dityrosine during minimization. Moreover, Tubulin (αT) (−11.0 kcal/mol) was identified as a target for cis-dityrosine (CDT), targets including αT (−11.2 kcal/mol) and thyroid hormone receptor beta-1 (−10.7 kcal/mol) presented high binding affinities for trans-dityrosine (TDT). Furthermore, in order to provide binding complexes with higher precision, the three docked systems were further refined by performing thermo dynamic simulations. A series of techniques for searching for the most stable binding pose and the calculation of binding free energy are elaborately provided in this work. The major interactions between these targets and dityrosine were hydrophobic, electrostatic and hydrogen bonding. The application of inverse virtual screening method may facilitate the prediction of unknown targets for known ligands, and direct future experimental assays. [ABSTRACT FROM AUTHOR]

Field measurement of water level is important for water conservancy project operation and hydrological forecasting. In this study, we proposed a new measuring technique by integrating the advantages of unmanned aerial vehicle (UAV) photogrammetry and image recognition technology. Firstly, the imagery of water fluctuation process was captured by an UAV airborne camera, and water surface line in the imagery was recognized and extracted using image recognition technology. Subsequently, successive water levels at a measuring section were calculated by parameter calibration. Statistical parameters of water levels, such as maximum, average, and minimum values during the capturing period were also calculated. Additionally, we introduced a correction method to offset the error caused by UAV drift. The newly proposed method was tested in field measurement for Miaowei hydropower station, China, and the results showed that the method is reliable and adoptable. [ABSTRACT FROM AUTHOR]

Because flammable organic solvents are emitted during the construction process, oil-based conductive coatings generally result in potential safety problems. A high content of conductive mediums can also weaken the adhesive and protective abilities of existing conductive coatings. Therefore, an anticorrosive and conductive coating was prepared on Q235 steel substrate by spraying the multi-walled carbon nanotubes (MWCNTs)/waterborne polyurethane (WPU) dispersion with a low MWCNT content in this work. The effect of the MWCNT content on the electrical conductivity, corrosion resistance, and adhesive strength of the WPU conductive coating was investigated. It was concluded that a spatial network structure of MWCNTs-WPU was formed to make the coating structure more compact. The electrical conductivity, corrosion resistance, and adhesive strength of the WPU conductive coating first increased and then decreased as the MWCNT content increased. When the MWCNT content was only 0.2 wt % (which was far lower than that of the existing conductive coatings at 1 wt %), the coating began to conduct electricity; its resistivity was 12,675.0 Ω·m. The best combination property was the 0.3 wt % MWCNTs/WPU conductive coating. Its adhesive strength was 19.99% higher than that of pure WPU coating. Its corrosion rate was about one order of magnitude lower than that of pure WPU coating after being immersed in 3.5 wt % NaCl solution for 17 days. [ABSTRACT FROM AUTHOR]

The absence of magnetic moments in pristine two-dimensional (2D) semiconducting materials has attracted many research interests. Transition-metal (TM) decoration has been found to be an effective strategy to introduce magnetic moments in non-magnetic 2D semiconductors. However, the stability of TM atoms modified 2D semiconductors has not been well explored. Here, taking 2D Tin (II) sulfide (SnS) monolayer as a prototype, we explored the stability of magnetic semiconductors through this method. In our studies, all possible configurations of TM decoration have been considered, namely, adsorption on the intact surface, S vacancy, and Sn vacancy. Based on the energy gain and electronic analysis, our results revealed that most of the TM atoms will form a cluster, and only several TM atoms can be effectively doped into the SnS monolayer. Furthermore, the band calculations showed that only Mn substitution will give rise to a magnetic semiconductor. Thus, the reported results here provide some hidden information for further realization of the magnetic semiconductors and serve as a paradigm to prepare 2D magnetic semiconductors. [ABSTRACT FROM AUTHOR]

To reveal the effects of water diversion from the Yangtze River to Lake Taihu on the phytoplankton habitat of the main water transfer channel of the Wangyu River, we investigated the water’s physicochemical parameters and phytoplankton communities during the water diversion and non-diversion periods over the winters between 2014–2016, respectively. During the water diversion periods in the winter of 2014 and 2015, the nutrients and organic pollutant contents of the Wangyu River channel were significantly lower than those during the non-diversion period in 2016. Moreover, the phytoplankton diversities and relative proportions of Bacillariophyta during the diversion periods evidently increased during the water diversion periods in winter. The increase in the water turbidity content, the decrease in the contents of the permanganate index, and the total phosphorus explained only 21.4% of the variations in the phytoplankton communities between the diversion and non-diversion periods in winter, which revealed significant contributions of the allochthonous species from the Yangtze River and tributaries of the Wangyu River to phytoplankton communities in the Wangyu River. The increasing gradient in the contents of nutrients and organic pollutants from the Yangtze River to Lake Taihu indicated the potential allochthonous pollutant inputs along with the Wangyu River. Further controlling the pollutants from the tributaries of the Wangyu River is critical in order to improve the phytoplankton habitats in river channels and Lake Taihu. [ABSTRACT FROM AUTHOR]

Dityrosine is the product of oxidation that has been linked to a number of serious pathological conditions. Evidence indicates that high amounts of dityrosine exist in oxidized milk powders and some milk related foodstuffs, further reducing the nutritional value of oxidized proteins. Therefore, we hypothesize that some receptors related to special diseases would be targets for dityrosine. However, the mechanisms of the interaction of dityrosine with probable targets are still unknown. In the present work, an inverse virtual screening approach was performed to screen possible novel targets for dityrosine. Molecular docking studies were performed on a panel of targets extracted from the potential drug target database (PDTD) to optimize and validate the screening results. Firstly, two different conformations cis- and trans- were found for dityrosine during minimization. Moreover, Tubulin (αT) (-11.0 kcal/mol) was identified as a target for cis-dityrosine (CDT), targets including αT (-11.2 kcal/mol) and thyroid hormone receptor beta-1 (-10.7 kcal/mol) presented high binding affinities for trans-dityrosine (TDT). Furthermore, in order to provide binding complexes with higher precision, the three docked systems were further refined by performing thermo dynamic simulations. A series of techniques for searching for the most stable binding pose and the calculation of binding free energy are elaborately provided in this work. The major interactions between these targets and dityrosine were hydrophobic, electrostatic and hydrogen bonding. The application of inverse virtual screening method may facilitate the prediction of unknown targets for known ligands, and direct future experimental assays.

This work describes the fabrication, characterization, and application of a gold microband array electrode (MAE) for the determination of phosphate in fresh water samples. The working principle of this MAE is based on the reduction of a molybdophosphate complex using the linear sweep voltammetric (LSV) method. The calibration of this microsensor was performed with standard phosphate solutions prepared with KH2PO4 and pH adjusted to 1.0. The microsensor consists of a platinum counter electrode, a gold MAE as working electrode, and an Ag/AgCl electrode as reference electrode. The microelectrode chips were fabricated by the Micro Electro-Mechanical System (MEMS) technique. To improve the sensitivity, gold nanoparticles (AuNPs) were electrodeposited on the working electrode. With a linear range from 0.02 to 0.50 mg P/L, the sensitivity of the unmodified microsensor is 2.40 µA per (mg P/L) (R2 = 0.99) and that of the AuNPs-modified microsensor is 7.66 µA per (mg P/L) (R2 = 0.99). The experimental results showed that AuNPs-modified microelectrode had better sensitivity and a larger current response than the unmodified microelectrode.

Hsp90 is involved in correcting, folding, maturation and activation of a diverse array of client proteins; it has also been implicated in the treatment of cancer in recent years. In this work, comparative molecular field analysis (CoMFA), comparative molecular similarity indices analysis (CoMSIA), molecular docking and molecular dynamics were performed on three different series of Hsp90 inhibitors to build 3D-QSAR models, which were based on the ligand-based or receptor-based methods. The optimum 3D-QSAR models exhibited reasonable statistical characteristics with averaging internal q(2) > 0.60 and external r(2) (pred) > 0.66 for Benzamide tetrahydro-4H-carbazol-4-one analogs (BT), AT13387 derivatives (AT) and Dihydroxylphenyl amides (DA). The results revealed that steric effects contributed the most to the BT model, whereas H-bonding was more important to AT, and electrostatic, hydrophobic, H-bond donor almost contributed equally to the DA model. The docking analysis showed that Asp93, Tyr139 and Thr184 in Hsp90 are important for the three series of inhibitors. Molecular dynamics simulation (MD) further indicated that the conformation derived from docking is basically consistent with the average structure extracted from MD simulation. These results not only lead to a better understanding of interactions between these inhibitors and Hsp90 receptor but also provide useful information for the design of new inhibitors with a specific activity.

An abnormal ubiquitin-proteasome is found in many human diseases, especially in cancer, and has received extensive attention as a promising therapeutic target in recent years. In this work, several in silico models have been built with two classes of proteasome inhibitors (PIs) by using 3D-QSAR, homology modeling, molecular docking and molecular dynamics (MD) simulations. The study resulted in two types of satisfactory 3D-QSAR models, i.e., the CoMFA model (Q(2) = 0.462, R(2) (pred) = 0.820) for epoxyketone inhibitors (EPK) and the CoMSIA model (Q(2) = 0.622, R(2) (pred) = 0.821) for tyropeptin-boronic acid derivatives (TBA). From the contour maps, some key structural factors responsible for the activity of these two series of PIs are revealed. For EPK inhibitors, the N-cap part should have higher electropositivity; a large substituent such as a benzene ring is favored at the C6-position. In terms of TBA inhibitors, hydrophobic substituents with a larger size anisole group are preferential at the C8-position; higher electropositive substituents like a naphthalene group at the C3-position can enhance the activity of the drug by providing hydrogen bond interaction with the protein target. Molecular docking disclosed that residues Thr60, Thr80, Gly106 and Ser189 play a pivotal role in maintaining the drug-target interactions, which are consistent with the contour maps. MD simulations further indicated that the binding modes of each conformation derived from docking is stable and in accord with the corresponding structure extracted from MD simulation overall. These results can offer useful theoretical references for designing more potent PIs.

In order to obtain structural features of 3-arylpyrimidin-2,4-diones emerged as promising inhibitors of insect γ-aminobutyric acid (GABA) receptor, a set of ligand-/receptor-based 3D-QSAR models for 60 derivatives are generated using Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Index Analysis (CoMSIA). The statistically optimal CoMSIA model is produced with highest q(2) of 0.62, r(2) (ncv) of 0.97, and r(2) (pred) of 0.95. A minor/bulky electronegative hydrophilic polar substituent at the 1-/6-postion of the uracil ring, and bulky substituents at the 3'-, 4'- and 5'-positions of the benzene ring are beneficial for the enhanced potency of the inhibitors as revealed by the obtained 3D-contour maps. Furthermore, homology modeling, molecular dynamics (MD) simulation and molecular docking are also carried out to gain a better understanding of the probable binding modes of these inhibitors, and the results show that residues Ala-183(C), Thr-187(B), Thr-187(D) and Thr-187(E) in the second transmembrane domains of GABA receptor are responsible for the H-bonding interactions with the inhibitor. The good correlation between docking observations and 3D-QSAR analyses further proves the model reasonability in probing the structural features and the binding mode of 3-arylpyrimidin-2,4-dione derivatives within the housefly GABA receptor.

Four new p-aminoacetophenonic acids, named (2E)-11-(4'-aminophenyl)-5,9-dihydroxy-4,6,8-trimethyl-11-oxo-undec-2-enoic acid (1), 9-(4'-aminophenyl)-3,7-dihydroxy-2,4,6-trimethyl-9-oxo-nonoic acid(2), (2E)-11-(4'-aminophenyl)-5,9-O-cyclo-4,6,8-trimethyl-11-oxo-undec-2-enoic acid (3) and 9-(4'-aminophenyl)-3,7-O-cyclo-2,4,6-trimethyl-9-oxo-nonoic acid(4), were isolated from an endophyte Streptomyces sp. (strain HK10552) of the mangrove plant Aegiceras corniculatum. The structures of 1-4 were elucidated by using spectroscopic analyses. The relative stereoconfigurations of compounds 3 and 4 were determined by NOESY experiments. In the bioassay test, 1-4 showed no cytotoxicity against the Hela cell lines. Compound 4 also showed no inhibitory bioactivity on HCV protease and SecA ATPase and wasn't active against VSVG/HIV-luc pseudotyping virus.