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Semantic segmentation of Polarimetric SAR (PolSAR) images is an important research topic in remote sensing. Many deep neural network-based semantic segmentation methods have been applied to PolSAR image segmentation tasks. However, a lack of effective means to deal with the similarity of object features and speckle noise in PolSAR images exists. Thisstudy aims to improve the discriminative capability of neural networks for various intensities of backscattering coefficients while reducing the effects of noise in PolSAR semantic segmentation tasks. Firstly, we propose pre-processing methods for PolSAR image data, which consist of the fusion of multi-source data and false color mapping. Then, we propose a Multi-axis Sequence Attention Segmentation Network (MASA-SegNet) for semantic segmentation of PolSAR data, which is an encoder–decoder framework. Specifically, within the encoder, a feature extractor is designed and implemented by stacking Multi-axis Sequence Attention blocks to efficiently extract PolSAR features at multiple scales while mitigating inter-class similarities and intra-class differences from speckle noise. Moreover, the process of serialized residual connection design enables the propagation of spatial information throughout the network, thereby improving the overall spatial awareness of MASA-SegNet. Within the decoder, it is used to accomplish the semantic segmentation task. The superiority of this algorithm for semantic segmentation will be explored through feature visualization. The experiments show that our proposed spatial sequence attention mechanism can effectively extract features and reduce noise interference and is thus able to obtain the best results on two large-scale public datasets (the AIR-POlSAR-Seg and FUSAR-Map datasets). [ABSTRACT FROM AUTHOR]

The partial replacement of chemical fertilizer with straw return is considered an effective method for improving the accumulation of organic matter and soil fertility, but the characteristics of soil nitrogen fixation and mineralization in a double-cropped rice paddy system are unclear. Based on a 12-year field experiment, we conducted a waterlogged incubation experiment for 49 days to determine the effect of long-term straw return combined with reducing chemical fertilizer application on the dynamic changes of mineralized soil nitrogen (N) content and mineralized N rate under the treatments, including NPK (chemical fertilizers application with straw removal), SBR (straw burned return), and SR (straw return). Results showed that, compared with SBR and NPK, SR significantly increased available nitrogen by 7.4% and 16.5%, respectively, due to the higher ammonium nitrogen and nitrate nitrogen, as well as the total carbon, available phosphorus, and slowly available potassium, suggesting that it could stock a sufficient nitrogen source. During the incubation period, the amount of N mineralization was relatively higher under SR than under SBR and NPK treatments, especially during the later mineralization time, whereas there was no difference in the N mineralization rate. In addition, SR significantly increased soil cumulative N mineralization and N mineralization potential. However, SBR significantly decreased the soil mineralizable N ratio compared with SR and NPK, which may result in a worsening of the N mineralization potential. The results indicated that long-term straw return combined with reducing chemical fertilizer application could significantly improve the N supply capacity of paddy rice field soil to better coordinate the soil N supply and immobilization. [ABSTRACT FROM AUTHOR]

• The characteristics of high-frequency oscillation in MMC-HVDC systems are analyzed and summarized by impedance method. • The influence of the parameters of passive filters on impedance shaping effect is analyzed and summarized. • A passive damping parameter design method which can be implemented based on "black box" model or simplified theoretical model of MMC station is presented in detail. • The proposed method reduces the capacity of the passive damping device while ensuring system stability margin. Recent years, there have been several high-frequency oscillation events in modular multilevel converter (MMC) based DC current projects. Considering the wideband oscillation characteristics of this issue, passive MMC impedance shaping methods are superior solutions for their advantages over the active methods in enhancing the broadband damping level. However, the optimization of parallel passive devices mainly focused on reactive power compensation and the suppression of characteristic harmonics generated by low-level inverters, which is not applicable to MMC systems. To address the optimization design problem of passive damping devices, this paper proposes an optimized design method for passive filters by analyzing the relationship between the passive damping device and the impedance shaping effect of the inverter. The proposed method reduces the capacity of the passive damping device while ensuring system stability margin. Finally, the effectiveness of the proposed passive impedance shaping strategy is verified through time-domain simulations considering changes in AC side operating conditions and power reduction operation of the MMC. [ABSTRACT FROM AUTHOR]

Background and Purpose: Currently available treatments do not halt progression of photoreceptor death and subsequent visual impairment related to retinal detachment (RD) which is observed in various retinal disorders. This study investigated the neuroprotective effects of two adrenoceptor ligands, the α1 -adrenoceptor antagonist doxazosin and the α2 -adrenoceptor agonist guanabenz, against photoreceptor cell death in RD.Experimental Approach: We used a model of experimental RD in Brown-Norway rats induced by subretinal injection of sodium hyaluronate. Oxidative stress biomarkers and cytokine production were quantified with elisa. Protein expression levels and immunofluorescent labelling were determined in rats with RD and controls for mechanistic elucidation. The effects of systemic (i.p.) administration of doxazosin or guanabenz on photoreceptor apoptosis, retinal histology and electroretinography were evaluated in rats with RD and compared to the effects in vehicle controls.Key Results: Photoreceptors were the major source of RD-induced ROS overproduction in the rat retina through the regulation of NADPH oxidase. Systemic administration of doxazosin or guanabenz decreased the RD-induced production of ROS and proinflammatory cytokines, including IL-1β and the chemokine CCL2, and suppressed retinal gliosis, resulting in attenuation of photoreceptor death and preservation of retinal structures and functions in RD.Conclusions and Implications: Our findings point to α-adrenoceptors as novel therapeutic targets to provide photoreceptor protection and suggest that both doxazosin and guanabenz, two FDA-approved drugs, could be further explored to treat retinal diseases. [ABSTRACT FROM AUTHOR]

Based on the standardized Euclidean distance method, an evaluation theory for sustainable agricultural development was constructed, which includes a sustainable agricultural development model, an evaluation function model, a sustainable agricultural development exponent (SADE), a rank of the sustainable agricultural development, an index frame of the sustainable agricultural development, a goal system, and a zero system. Data from Zhenyuan County of Gansu province (ZYC) between 2000 and 2012 was used as a case study of the theory. The SADE of ZYC was [0.34, 0.90], and the agriculture system exhibited low sustainability from 2000 to 2003, mid sustainability from 2004 to 2007, and high sustainability from 2008 to 2012. The results explained the actual ZYC situation, and showed that the Euclidean distance method of sustainable agricultural development is feasible. The innovativeness and merits of the method include: (1) reliable methodology, (2) construction using goal and zero systems, which serve as reference systems of sustainable agricultural development and allow control of the evaluation, and (3) index weights embedded in the evaluation function, which prevents errors or mistakes in the expert scoring method and prevents the reassignment of index weights due to adding or subtracting indicators. The main reasons that the SADE increased in ZYC include suitable chemical fertilization and pesticide application, enhancement of conservation farming areas, soil testing and fertilizer-formulated areas, and drinking water security in rural and non-disaster crop areas. The main problems with increasing the SADE in ZYC include straw application and low farmer income, both of which should be increased. [ABSTRACT FROM AUTHOR]

Purpose. To quantify macular vascular density using optical coherence tomography angiography (OCTA) and to investigate its relationship with retinal thickness in myopic eyes of young adults. Methods. In this cross-sectional study, 268 myopic eyes without pathological changes were recruited and divided into three groups: mild myopia (n=81), moderate myopia (n=117), and high myopia (n=70). Macular vascular density was quantified by OCTA and compared among three groups. Average retinal thickness, central subfield thickness, and macular ganglion cell complex (mGCC) thickness were also evaluated and compared. Correlations among these variables were analyzed. Results. There was no statistical difference in superficial (62.3 ± 5.7% versus 62.7 ± 5.9% versus 63.8 ± 5.5%) and deep macular vascular densities (58.3 ± 9.6% versus 59.2 ± 9.3% versus 60.9 ± 7.9%) among mild-myopia, moderate-myopia, and high-myopia groups (both P>0.05). Superficial and deep macular vascular densities both had correlations with mean arterial pressure. Furthermore, superficial macular vascular density was significantly correlated with mGCC thickness. Conclusions. Varying degrees of myopia did not affect macular vascular density in young healthy adults. In addition, superficial macular vascular density, as an independent factor, was positively correlated with mGCC thickness. [ABSTRACT FROM AUTHOR]

Soy sauce aroma type baijiu (SSAB) is one of the four basic baijiu flavor types. It has an elegant sauce flavor, empty cup aroma, lasting, mellow and sweet entrance, soft with obvious acidity, delicate taste and long aftertaste. However, to date, no study has identified the key aroma compounds in SSAB. This study introduces SSAB and its production process, and summarizes the research status on flavor compounds. Through analysis and review, some assumptions are made to explain why the key aroma compound of SSAB remains unidentified. We provide insights for the analysis of key aroma compounds in SSAB and lay a theoretical foundation for the improvement and rapid development of SSAB quality. • Specific summarizes the research of key volatile compounds in soy sauce aroma type baijiu. • Summarizes the research of off-odor components in soy sauce aroma type baijiu. • First time to analyzes why the key flavor of soy sauce aroma type baijiu have not been discovered. [ABSTRACT FROM AUTHOR]

• A steady cone-jet occurs in a greater range of liquid flow rates for a hemispherical capillary. • Varicose and whipping regimes are easily obtained with a hemispherical nozzle. • The transition from varicose and whipping usually depends on interfacial forces on the jet. • A general parameter to determine varicose, transition, and whipping regimes is presented. A cone-jet regime in electrohydrodynamic atomization (EHDA) is widely applied into printing, electro-spinning, spray-coating, and biological mass spectrometry. Regulating different instabilities of jet is crucial for optimizing its operating parameters. In present work, an atypical, hemispherical capillary with inner diameter of 0.40 mm and cap size of 6.20 mm was employed as atomization nozzle, through which a steady cone-jet regime was confirmed versus suitable feeding liquid flow rate and electric potential. A permanent and highly charged jet emits from a Taylor cone apex and further disintegrates into fine highly charged drops in the form of varicose or whipping instabilities. The results indicate that a steady cone-jet is observed in the specific ranges of the feeding liquid flow rate, electric potential and conductivity. The typical breakup instabilities including varicose and whipping are clearly observed with an increase in liquid flow rate for a fixed electric potential for most of liquids, and the transition from varicose to whipping instability easily occurs. For a steady cone-jet, the jet breakup instabilities usually depends on the competition between interfacial forces on the electrified jet. The transition process involving a low-viscosity jet with a large flow rate is observed, and the general parameter G = Γ 2 δ μ 0.52 is calculated to account for surface charge, surface tension, and viscosity effects, where Γ is the electric force to surface tension ratio and δ μ is the inertia to viscous force ratio. Finally, the varicose, transition regime, and whipping are classified with first and second critical threshold values G = 40 and G = 102, respectively. Meanwhile, as the electrified jet transforms from varicose to whipping instabilities, the jet breakup length shows a trend of increasing first and then decreasing. [ABSTRACT FROM AUTHOR]

• The necking time is independent of electric field in a reasonable range of flow rate. • The transition from dripping to jetting is enhanced by electric field for relatively small tube. • A model for the transition from periodic dripping to jetting is established in an electric field. • A critical criterion for the transition is presented and in reasonable agreement with experiments. A liquid is issued from the outlet of the capillary tube vertically, and drop formation may be in the form of periodic dripping, dripping faucet and jetting, which usually depends on flow rate or Weber number. We consider the critical Weber number (W e C = ρV 0 2 D / σ) at which the transition from periodic dripping to jetting occurs in the presence of an electric field, where high-resolution images are recorded. The necking time is mainly related to nozzle diameter and surface tension, and independent of electric potential and flow rate (in a reasonable range).The first threshold limit decreases with an increase in electric potential, where the dripping faucet is clearly affected and the point of drop detachment gradually increases. When the drop formation is in the form of dripping faucet, the transition from dripping faucet to jetting regime is enhanced by electric potential, where a sudden transition could be observed in an extremely limited range of liquid flow rate. The critical criterion (Weber number) is presented to determine the transition from dripping to jetting in the presence of an electric field. The critical Weber number is in a reasonable agreement with the experiment, although the predicted results are quantitatively divergent with experimental data. [ABSTRACT FROM AUTHOR]

Baijiu is a unique and traditional distilled liquor in China. Flavor plays a crucial rule in baijiu. Up to now, the research on the flavor of baijiu has progressed from the identification of volatile compounds to the research on key aroma compounds, but the release mechanism of these characteristic compounds is still unclear. Meanwhile, volatile compounds account for only a tiny fraction, whereas ethanol and water account for more than 98% of the content in baijiu. By summarizing the ethanol–water hydrogen bond structure in different alcoholic beverages, it was found that flavor compounds can affect the association strength of the ethanol–water hydrogen bond, and ethanol–water can also affect the interface distribution of flavor compounds. Therefore, the research on ethanol–water microstructure in baijiu is helpful to realize the simple visualization of adulteration detection, aging determination and flavor release mechanism analysis of baijiu, and further uncover the mystery of baijiu. [ABSTRACT FROM AUTHOR]

Thrombospondin-1 (TSP1) is a multidomain protein that contains epidermal growth factor (EGF)-like repeats that indirectly activate the EGF receptor (EGFR) and selected downstream signaling pathways. In these studies, we show that TSP1 opens the paracellular pathway in human lung microvascular endothelial cells (HMVEC-Ls) in a dose-, time-, and protein tyrosine kinase (PTK)-dependent manner. TSP1 increased tyrosine phosphorylation of proteins enriched to intercellular boundaries including the zonula adherens (ZA) proteins, vascular endothelial-cadherin, γ-catenin, and p120 catenin. In HMVEC-Ls, EGFR and ErbB2 are expressed at low levels, and both heterodimerize and tyrosine autophosphorylate in response to TSP1. Prior EGFR-selective PTK inhibition with AG1478 or ErbB2-selective PTK inhibition with AG825 protected against TSP1-induced tyrosine phosphorylation of ZA proteins and barrier disruption. Preincubation of HMVEC-Ls with an EGFR ectodomain-blocking antibody also prevented TSP1-induced opening of the paracellular pathway. Therefore, in HMVEC-Ls, TSP1 increases tyrosine phosphorylation of ZA proteins and opens the paracellular pathway, in part, through EGFR/ErbB2 activation. Surprisingly, recombinant TSP1 EGF-like repeats 1-3 and the high-affinity EGFR ligands, EGF, TGF-α, and amphiregulin, each failed to increase paracellular permeability. However, HMVEC-Ls in which EGFR was overexpressed became responsive to the EGF-like repeats of TSP1 as well as to EGF. These studies indicate that TSP1 disrupts the endothelial barrier through EGFR/ErbB2 activation although additional signals are necessary in cells with low receptor expression. [ABSTRACT FROM AUTHOR]

Presents a study which determined whether fatty liver vulnerability to lipopolysaccharide damage occurs due to upregulated protective, antiapoptotic mechanisms. Background on liver diseases; Materials and methods; Results and discussion.

Under the influence of space weather, abnormal disturbances in the ionosphere will distort the ionosphere model seriously and affect the global navigation satellite system negatively. This study analyzes the ionospheric activity characteristics and the ionospheric model performance in low latitude during a strong geomagnetic storm from 7 to 9 September 2017. The research goals are to determine the abnormal behavior of the ionosphere during the geomagnetic storm and to refine the ionosphere model in the low latitude. In the experiment, the vertical total electron content (VTEC) peak value at low latitudes caused by this geomagnetic storm was significantly higher than that on the geomagnetic quiet day, and the VTEC peak value increased by approximately 75%. In the main phase of the geomagnetic storm, the degree of VTEC variation with longitude is significantly higher than that of the geomagnetic quiet day. The VTEC variation trend in the northern hemisphere is more severe than that in the southern hemisphere. In the region where VTEC decreases with longitude, the VTEC in the northern hemisphere is higher than that in the southern hemisphere on the same longitude at low latitudes, and this phenomenon is not significantly affected by the geomagnetic disturbance of the recovery phase. During the geomagnetic storm, the daily minimum value of VTEC at different latitudes was basically the same, approximately 5 TECU, indicating that the nighttime VTEC of the ionosphere in low latitudes was weakly affected by latitude and geomagnetic storms. Geomagnetic disturbances during geomagnetic storms will lead to anomalous features of the "Fountain effect" in the ionosphere at low latitudes. In addition, this geomagnetic storm event caused the accuracy of spherical harmonics (SH), polynomial, and ICE models to decrease by 7.12%, 27.87%, and 48.56%, respectively, and caused serious distortion, which is negative VTEC values fitted by the polynomial model. [ABSTRACT FROM AUTHOR]

Currently, research on the small-signal stability of grid-forming converters under two control modes, grid-following and grid-forming, mainly focuses on low-level converters. However, studies on the differences between grid-following modular multilevel converters (MMC) and grid-forming MMC are limited. A comprehensive analysis of the wideband oscillation risk differences in MMC-HVDC systems under these two control modes from the perspective of impedance characteristics is necessary. Therefore, based on the harmonic state-space (HSS) modeling theory, this article establishes wideband sequence impedance models for grid-forming and grid-following MMC. Subsequently, this article identifies key control parameters affecting the impedance characteristics of MMC under two control modes. The wideband oscillation risks of MMC-HVDC systems under both control modes are compared. The study indicates that when the grid strength weakens, grid-following MMC faces instability risks, while grid-forming MMC can maintain stability. In instances where high-frequency resonance peaks exist in the impedance of the grid, both control modes of MMC may face instability risks. Furthermore, by adjusting the obtained key control parameters of MMC, this article effectively suppresses the oscillation risk discussed above. Finally, the analysis results are verified through an electromagnetic transient simulation. [ABSTRACT FROM AUTHOR]

Hydrocarbons with four carbons in their molecular structure (C4s) represent an important chemical family in the modern petrochemical industry. Converting less valuable C4s into more valuable C4s with effective separation has been of significant industrial interest. The large variety of C4s leads to a complex reaction pathway network. Prior work carried out on C4 modelling and optimisation has been largely industry-focussed with limited studies found in academic publications. This work aims to bridge the research gap by developing a systematic methodology that can identify the optimal process pathways for maximum economic return. A superstructure network is developed, showing comprehensive pathways for C4 processing. Mathematical programming is applied to model the superstructure with individual processing units, in which simplified process models used in the network model can be supported by detailed process models. Optimisation is implemented in GAMS, the results of which help gain important physical insights into the best options for C4 processing. [ABSTRACT FROM AUTHOR]

A two-stage process has been developed for the pyrolysis of high-density polyethylene to obtain light olefins, where probable mechanisms for each stage pyrolysis were proposed in our previous study. This work aims to establish molecular-level kinetic models for the first-stage pyrolysis at a lower temperature and for the second-stage pyrolysis at a higher temperature, respectively, to predict the overall reaction performances in accordance to the role of detailed mechanisms. A structure-oriented lumping (SOL) method based molecular-level kinetic model can effectively describe the first-stage pyrolysis, while a detailed molecular-level kinetic model is developed for the second-stage pyrolysis to track the evolutions of all alkanes, olefins, and diolefins, with special focus on the formation of light olefins. The established separate models can achieve the automatic generation of complex reaction networks and present good agreement with experimental data obtained from the first- and second-stage. In addition, the first-stage model indicates that the random scission plays an important role in the pyrolysis process at lower temperatures, while the chain-end scission mechanism dominates the second-stage reaction to produce light olefins at higher temperatures. As a whole, the molecular-level modelling scheme behaves excellently at a wide range of temperature, which provides guidance for upgrading the pyrolysis process. • A molecular level kinetic model is established for the two-stage HDPE pyrolysis. • The reaction network is generated automatically and visualized. • This model achieves excellent agreement with experimental data. • The competition of two scissions and important role of temperature are quantified. [ABSTRACT FROM AUTHOR]

• The onset and termination electric potential to form the steady cone-jet electrospray increase as conductivity increasing. • The lower and upper limitation of liquid flowrate to form the steady cone-jet electrospray decrease as conductivity increases. • The varicose instability can transform into whipping instability as the electrical conductivity increasing. • The jet breakup instability transition mechanism is interpreted by theoretical analysis. • The whipping to similar micro-dripping instability can be observed for EG with higher conductivity. In present work, the effect of the electrical conductivity on the steady cone-jet electrospray are experimentally investigated, where the operating diagram and the jet breakup instability are extensively examined. A hemispherical tube is employed as spraying nozzle severed as high electric potential electrode in a needle-plated electrode configuration compared to the common and sheathed tubes. The cone-jet electrospray is visualized by a high-resolution camera and extensively analyzed offline. The aqueous solution in ethanol, Diethyleneglycol (DEG) and Ethylene glycol (EG) are atomized with varied electrical conductivity under different high electric potentials and flowrates. Experimental results indicate that the cone-jet electrospray can operate in the certain ranges of operating parameter for all types of capillaries. The operating diagram for the hemispherical tube is significantly broader than other tubes because of various electric field strength distribution. The onset electric potential to determine a steady cone-jet electrospray gradually increases and the termination value also increases as the electrical conductivity increases. The lower and upper flowrate to form a steady cone-jet electrospray also increase as the electrical conductivity increases. The jet breakup instability can transit from varicose to whipping due to low the reference flow rate as electrical conductivity increases, which is agreement with theoretical analysis. In particular, for EG, the transition from whipping to similar micro-dripping is observed as the electrical conductivity increases, while the transition also occurs as flowrate increases for EG with higher electrical conductivity. The increase in the electrical conductivity and flowrate elongates the cone due to EHD body force, which causes the electric field varying, further resulting in the difference in jet breakup instability. Moreover, the electrical conductivity also plays an important role in jet breakup length. The instability variation of jet with conductivity (DEG), q V =1000 nL/s, ϕ =8.00 kV (Hemispherical nozzle with D o =0.70mm); The variation with liquid flow rate of EG with higher conductivity (K =8.5 × 10−4 s/m, ϕ =10.20 kV, (Hemispherical nozzle with D o =0.70mm) [Display omitted] [ABSTRACT FROM AUTHOR]

Maize is one of the most successful crops with regard to the utilization of heterosis. The haploid induction technique is one of the fastest methods to obtain pure maize material at the present stage. However, the molecular mechanism of haploid doubling is rarely reported. In this study, we treated B73 and ZNC442 haploid young shoots with colchicine for 0 h, 6.2 h, and 10 h, and analyzed the differentially expressed genes (DEGs). We found that colchicine treatment for 6.2 h and 10 h compared to 0 h resulted in a total of 4868 co-DEGs. GO enrichment analysis and KEGG metabolic pathway analysis found significantly enriched 282 GO terms and 31 significantly pathways, respectively. Additionally, The GO term and KEGG pathway genes of spindle, cytoskeleton, microtubules and nuclear division were selected for analysis, and three candidate genes were screened by taking intersections. Zm00001d033112, Zm00001d010525, and Zm00001d043386 were annotated as kinesin-associated protein 13, kinesin-like protein KIN-10C, and kinesin light-chain LC6, respectively. The real-time fluorescence quantification (RT-PCR) results revealed that Zm00001d033112, Zm00001d010525, and Zm00001d043386 had the same trends as RNA-seq. Interestingly, Zm00001d033112 is homologous gene AT3G20150 in Arabidopsis, which was involved in the regulation of chromosome movement and mitotic spindle assembly. Our study suggests that kinesin genes may play an important role in doubling chromosomes, thus providing valuable information for future studies on the molecular mechanisms of chromosome doubling in maize. [ABSTRACT FROM AUTHOR]

Developing production technology pathways of sustainable aviation fuel (SAF) that align with China's national conditions and aviation transportation needs is crucial for promoting the SAF industry and achieving China's carbon peak and carbon neutrality goals. This article first projects the future SAF demand in China for the coming decades. Using SAF demand data as an input, this article employs the TOPSIS analysis method to comprehensively evaluate the suitability of four SAF production technology pathways at different stages of development in China, which are Hydroprocessed Esters and Fatty Acids (HEFA), Alcohol-to-Jet (AtJ), Natural Gas + Fischer–Tropsch Synthesis (G + FT), and Power-to-Liquid (PtL). The research results reveal the following trends: HEFA-based processes are the most suitable technology pathways for China in the near term; the G + FT route, based on energy crops, appears the most likely to support civil aviation needs in the medium to long term. In the long run, the PtL route holds significant potential, especially with the decreasing costs of green electricity, advancements in carbon capture, utilization, and storage (CCUS) technology, and improvements in SAF synthesis methods. In the final section of this article, we provide recommendations to drive the development of the SAF industry in China. [ABSTRACT FROM AUTHOR]

The pollution of heavy metals is extremely serious in China, including zinc (Zn), copper (Cu), lead (Pb), and cadmium (Cd). Heavy-metal-transporting ATPase (HMA) belongs to a subfamily of the P-ATPase family, which absorbs and transports Zn, Cu, Pb, and Cd in plants. Here, we describe a ZmHMA-encoding HMA family protein that positively regulates Cd and Zn tolerance. The real-time fluorescence quantification (RT-PCR) results revealed that ZmHMA3 had a high expression in B73, and the expression of ZmHMA3 was sensitive to Cd in yeast cells, which was related to Cd accumulation in yeast. Additionally, the Arabidopsis thaliana homologous mutants of AtHMA2 showed Cd sensitivity compared with WT. The overexpressing ZmHMA3 plants showed higher tolerance under Cd and Zn stresses than the wild type. The overexpression of ZmHMA3 led to higher Cd and Zn accumulation in tissues based on the subcellular distribution analysis. We propose that ZmHMA3 improves maize tolerance to Cd and Zn stresses by absorbing and transporting Cd and Zn ions. This study elucidates the gene function of the ZmHMA3 response to Cd and Zn stress and provides a reference for improving the characteristics of heavy metals enrichment in existing maize varieties and the plant remediation technology of heavy-metal-contaminated soil. [ABSTRACT FROM AUTHOR]

Waste plastics have emerged as a global environmental issue. Polyethylene, accounting for about 25% of global plastic production, has been acknowledged as the major cause of "white pollution". In this paper, a generalized molecular-level kinetic model was proposed to understand the pyrolysis of polyethylene applying structure-oriented lumping, Poisson distribution, and genetic algorithm. The number of ordinary differential equations derived from the reaction kinetics were dramatically reduced by this simplified network with 14-rule design. The generalizability was confirmed by case studies without any change in the rule design. Under most conditions, the mean relative error between experimental and model data could be controlled within 5%, while abnormal deviations indicate the obstacle of heat transfer. The simulation curve could provide guidance for the experiments by locating the peak value of products. From 400–470 °C in Case 2, the increase in the reaction proportion of producing light oil explains the experimental results from the perspective of molecular-level reaction network. The comparison between PE and PS pyrolysis elaborates different pyrolysis mechanisms based on the different molecular structures. • Established a generalized molecular-level model for polyethylene pyrolysis. • Offered an efficient tool avoiding repeated work in pyrolysis simulation. • Confirmed the generalizability by case studies without changing the rule design. • Provided guidance for the experiments by locating the peak value of products. [ABSTRACT FROM AUTHOR]

The accumulation of waste plastics has been one of the most urgent and difficult environmental challenges. In this work, the pyrolysis of polyethylene (PE) has been studied by thermogravimetric analysis (TGA), pyrolysis/gas chromatography/mass spectrometry (PyGC-MS), and a two-stage tube reactor. The pyrolysis behavior of high-density polyethylene (HDPE) and low-density polyethylene (LDPE) is compared, and there are almost no differences in the thermogravimetric curves obtained by TGA and the yield of gaseous products obtained in a two-stage process. The evolution of light olefins (C 2 –C 4) during the pyrolysis of PE is investigated in a two-stage process with a constant condition in the first stage (500 °C) and various conditions in the second stage (700–1000 °C, 0.2–0.4 s). The temperature in the second stage has a more significant effect on the yield and selectivity of light olefins than the residence time, and the ethylene, propylene, and butene yields do not increase monotonously as the temperature rises. The highest yield of light olefins of 76.1 wt% is obtained at 800 °C with a selectivity of 91.7%. The maximum yields of ethylene, propylene, and butene are 45.1 wt%, 17.3 wt%, and 24.3 wt%, respectively. The scission mechanisms are proposed to provide insight into the process during which PE molecules transform into light olefins. • There are almost no differences between the pyrolysis characteristics of high-density and low-density polyethylene. • The evolution of light olefins during the polyethylene pyrolysis is investigated by PyGC-MS and a two-stage tube reactor. • A high yield of light olefins of 76.1 wt% with a high selectivity of 91.7% is obtained at 800 °C. • Probable mechanisms for two-stage pyrolysis of PE are proposed to reveal the interplay of reactions. [ABSTRACT FROM AUTHOR]

The accuracy of insulators and their defect identification by UAVs (unmanned aerial vehicles) in transmission-line inspection needs to be further improved, and the model size of the detection algorithm is significantly reduced to make it more suitable for edge-end deployment. In this paper, the algorithm uses a lightweight GhostNet module to reconstruct the backbone feature extraction network of the YOLOv4 model and employs depthwise separable convolution in the feature fusion layer. The model is lighter on the premise of ensuring the effect of image information extraction. Meanwhile, the ECA-Net channel attention mechanism is embedded into the feature extraction layer and PANet (Path Aggregation Network) to improve the recognition accuracy of the model for small targets. The experimental results show that the size of the improved model is reduced from 244 MB to 42 MB, which is only 17.3% of the original model. At the same time, the mAp of the improved model is 0.77% higher than that of the original model, reaching 95.4%. Moreover, the mAP compared with YOLOv5-s and YOLOX-s, respectively, is improved by 1.98% and 1.29%. Finally, the improved model is deployed into Jetson Xavier NX and run at a speed of 8.8 FPS, which is 4.3 FPS faster than the original model. [ABSTRACT FROM AUTHOR]

With the increasing proportion of renewable power generations in the power system, the power grid impedance may fluctuate greatly, and it is difficult for the virtual synchronous generator (VSG) with a single control structure to meet the stability requirements. Thus, the control principles of the two types of VSGs are compared to conclude that there are similarities in the control structure of the two VSGs. And the small signal models of the two types of VSGs are established to analyze the stability boundaries, coming to the conclusion that the stability region is complementary. Based on the conclusions, the paper puts forward the idea of switching operation modes: switch to the U‐VSG mode when the grid strength weakens and switch to the PQ‐VSG mode when greater, so that the inverter can keep stable in a wider range of grid strength. Therefore, the characterization method of the switching boundary with hysteresis properties is proposed. Then the improved recursive least squares (RLS) algorithm is introduced to identify the power grid impedance online without additional injected disturbance, based on which the adaptive multi‐mode smooth switching control strategy is proposed. Finally, the effectiveness of the analysis and the control strategy are verified by simulations. [ABSTRACT FROM AUTHOR]

High-energy lithium-ion batteries (LIBs) have been actively pursued for practical applications in advanced electric vehicles and large-scale energy storage systems. The silicon (Si) material has been considered as a promising anode candidate due to its impressive lithium storage capacity, but is facing the challenge to ameliorate its cycling and rate performance. We here report a structure integration strategy to overcome major issues of poor capacity retention and slow kinetics during the lithium storage of Si anode, through in situ embedding Si nanoparticles into V 2 C MXene nanosheets. The MXene-supported Si@V 2 C nanocomposite anode reveals significantly enhanced cycling stability and improved lithium storage kinetics compared to that of the pristine Si anode. A high capacity exceeding to 430 mAh g−1 can be retained for 150 cycles at 200 mA g−1 current density. In addition, the conductive MXene supporter has been demonstrated to facilitate lithiation/delithiation processes for the Si by enhancing the charge transfer kinetics, as it is demonstrated by in situ electrochemical impedance spectroscopic (EIS) and Galvanostatic Intermittent Titration Technique (GITT) measurements. Findings from this work may inspire feasible structural designs for the practical deployment of MXene composited Si anode materials for next-generation lithium-ion batteries. [Display omitted] • Si@V 2 C composite anode was explored using V 2 C MXene as supporting substrate with enhanced Si stability performance. • A high capacity of 430 mAh g−1 can be retained for 150 cycles at 200 mA g−1 current density. • The V 2 C MXene can provide improved electronic conductivity and structural support of the Si anode during cycling. [ABSTRACT FROM AUTHOR]

Our study developed the one-step catalytic cracking conceptual design using a two-stage riser reactor (OSCO). Molecular-level process models and multi-objective optimization strategies are also carried out. Results show that the OSCO process exhibits superior techno-economic, society, people's livelihood, and environmental performance. [Display omitted] • A novel process is proposed to crack naphtha, kerosene, diesel and heavy oil in the two-stage riser reactor efficiently. • A novel integration model of mixed fraction structure and molecular level is proposed. • The multi-objective optimization strategies using systematic solution algorithm are performed. • The novel process shows superior techno-economic, society, people's livelihood, and environmental performance. With the demand for vehicle fuels (i.e., gasoline and diesel) is expected to decline soon, crude oil to chemical technology exhibits great potential to drive the next industry transition. This megatrend has led to studies on maximizing the production of low-carbon petrochemicals at the cost of fuels, which requires aggressive ways of converting oil into chemicals in a clean and efficient pattern. Herein, we proposed a novel process, termed OSCO, to crack naphtha, kerosene, diesel and heavy oil in a two-stage riser reactor efficiently, which can perform several refining procedures in the two-stage riser reactor vessel. A novel integration model of mixed fraction structure and molecular level is proposed. The multi-objective optimization strategies are also carried out to solve the optimization problem. As a result, the OSCO process can stably convert untreated heavy Daqing crude oil into light olefins with total yields of ethylene and propylene over 33 wt%, which also exhibits superior techno-economic, society, people's livelihood, and environmental performance. These insights may have a positive pushing role in engineering design, process intensification, and the optimization of direct catalytic cracking of crude oil. [ABSTRACT FROM AUTHOR]

Background: The development of diabetes vascular calcification (VC) is tightly associated with the inhibition of vascular smooth muscle cell (VSMC) autophagy. Previously, our team found that miR-32-5p (miR-32) promotes macrophage activation, and miR-32 is expressed at higher level in the plasma of patients with coronary calcification. However, whether miR-32 mediates the function of macrophages in type 2 diabetes (T2D) VC is still unclear.Methods: Wild-type (WT) and miR-32-/- mice were used in this study. qRT-PCR and western blotting were used to analyze gene expression. Flow cytometry was used to analyze the influence of glucose concentration on macrophage polarization. Nanoparticle tracking analysis (NTA), transmission electron microscopy, and confocal microscopy were used to identify macrophage extracellular vehicles (EVs). Immunofluorescence, in situ hybridization (ISH), immunohistochemistry, and alizarin red staining were used to analyze the influence of macrophage EVs on autophagy and calcification of the aorta of miR-32-/- mice. A luciferase assay was used to analyze the effect of miR-32 on myocyte enhancer factor 2D (Mef2d) expression. Co-IP combined with mass spectrometry (MS) and transcriptome sequencing was used to analyze the signalling pathway by which Mef2d acts in VSMC autophagy.Results: We found that high glucose conditions upregulate miR-32 expression in macrophages and their EVs. Importantly, macrophages and their EVs promote VSMC osteogenic differentiation and upregulate miR-32 expression in VSMCs. Moreover, miR-32 mimics transfection promoted osteogenic differentiation and inhibited autophagy in VSMCs. In vitro and in vivo experiments showed that Mef2d is the key target gene of miR-32 that inhibits VSMC autophagy. Furthermore, MS and transcriptome sequencing found that cGMP-PKG is an important signalling pathway by which Mef2d regulates VSMC autophagy. In addition, after T2D miR-32-/- mice were injected with macrophage EVs via the caudal vein, miR-32 was detected in aortic VSMCs of miR-32-/- mice. Moreover, autophagy was significantly inhibited, and calcification was significantly enhanced in aorta cells.Conclusions: These results reveal that EVs are the key pathway by which macrophages promote T2D VC, and that EVs miR-32 is a key cause of autophagy inhibition in VSMCs. [ABSTRACT FROM AUTHOR]

Soil moisture (SM) is an important land-surface parameter. Although microwave remote sensing is recognized as one of the most appropriate methods for retrieving SM, such retrievals often cannot meet the requirements of specific applications because of their coarse spatial resolution and spatiotemporal data gaps. A range of general models (GMs) for SM analysis topics (e.g., gap-filling, forecasting, and downscaling) have been introduced to address these shortcomings. This work presents a novel strategy (i.e., optimized wavelet-coupled fitting method (OWCM)) to enhance the fitting accuracy of GMs by introducing a wavelet transform (WT) technique. Four separate GMs are selected, i.e., elastic network regression, area-to-area regression kriging, random forest regression, and neural network regression. The fitting procedures are then tested within a downscaling analysis implemented between aggregated Global Land Surface Satellite products (i.e., LAI, FVC, albedo), Thermal and Reanalysis Integrating Medium-resolution Spatial-seamless LST, and Random Forest Soil Moisture (RFSM) datasets in both the WT space and the regular space. Then, eight fine-resolution SM datasets mapped from the trained GMs and OWCMs are analyzed using direct comparisons with in situ SM measurements and indirect intercomparisons between the aggregated OWCM-/GM-derived SM and RFSM. The results demonstrate that OWCM-derived SM products are generally closer to the in situ SM observations, and better capture in situ SM dynamics during the unfrozen season, compared to the corresponding GM-derived SM product, which shows fewer time changes and more stable trends. Moreover, OWCM-derived SM products represent a significant improvement over corresponding GM-derived SM products in terms of their ability to spatially and temporally match RFSM. Although spatial heterogeneity still substantially impacts the fitting accuracies of both GM and OWCM SM products, the improvements of OWCMs over GMs are significant. This improvement can likely be attributed to the fitting procedure of OWCMs implemented in the WT space, which better captures high- and low-frequency image features than in the regular space. [ABSTRACT FROM AUTHOR]

[Display omitted] • A rational coating-integrated-into-synthesis design was used to prepare surface Ti-enriched NMC811 material. • The Ti substitute has a unique tri-valence (Ti3+) in a gradient surface distribution. • The surface Ti-enriched NMC811has high cationic ordering both in the bulk and surface. • Theoretical simulations certify enhanced stability of lattice oxygen for the NMC811#Ti material. • The NMC811#Ti cathode shows improved cycling performance and thermal/ storage stabilities. High-Ni cathodes are being intensely pursued worldwide for electric vehicles and other energy-dense applications due to their high capacity and low cost. However, structural instabilities during electrochemical cycling and when subjected to thermal treatment have been the major issues hindering their practical deployment. We here report a rational design of coating-integrated-into-synthesis protocol for fabricating surface Ti-enriched LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NMC811#Ti) material. The coating to intermediates is crucial to obtain high structural ordering, both in the bulk and surface of high-Ni cathodes, and the Ti substitute has a unique tri-valence (Ti3+) in a gradient surface distribution. The simulations of projected density of states in the atomistic understanding further certify significantly enhanced stability of lattice oxygen for the NMC811 through such a Ti3+-based structure reinforcement. Consequently, the NMC811#Ti cathode delivers a high capacity up to 200 mAh g−1 at 0.1 C, along with superior stabilities during air-storage and thermal treatment (up to 297 °C at the fully charged state under differential scanning calorimetric measurements). The corresponding NMC811#Ti||graphite full cell exhibits a desired 83.6 % capacity retention after 1000 cycles at 0.5 C in a voltage range of 2.8–4.3 V. This work demonstrates a delicate surface reinforcement to stabilize high-Ni cathodes for long-life and safe lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Rapid urbanization has brought about many problems in urban environments, including the deterioration of the thermal environment, which greatly affects the sustainable development of cities and the health of urban residents. Therefore, a comprehensive and thorough study of the thermal environment is necessary. In this study, quantitative and qualitative analyses of the interannual and seasonal variation of the thermal environment in the urban area of Chongqing were conducted using a combination of equal sector analysis, mathematical statistics, and principal component analysis. In addition, the mechanism by which multiple integrated human and natural factors affect the urban thermal environment in different seasons was explored. The thermal environment of the land surface has a clear spatial correlation with built-up areas. From 2010 to 2020, the Liangjiang New Area and the western high-tech zone were the main areas of thermal environment area expansion. From 2010 to 2020, a decrease in the area of low-temperature zones and an increase in the area of high-temperature zones were the main trends. In particular, during the summer of 2020, the low-temperature zones almost disappeared, and the area of high-temperature zones was nearly twice as large as in the other seasons. The combined influence of multiple factors on surface temperature has certain seasonal characteristics. The slope, elevation, normalized water body index, fractional vegetation cover, normalized imperviousness index, and nighttime light intensity were the main factors affecting the surface temperature, whereas landscape pattern indicators, as well as the population and points of interest (POI) density, had a low influence. The strength of the combined influence of these multiple factors of the different seasons exhibited the following order: winter > spring > summer > autumn. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel, potent and effective EZH2 degraders were developed. • Compound P4 can effectively induce EZH2 protein degradation and inhibit breast cancer cell growth. • Compound P4 can significantly decrease the degree of H3K27me3 in MDA-MB-231 cell line, induce apoptosis and G 0 /G 1 phase arrest in Pfeiffer and MDA-MB-231 cell lines. • Compound P4 significantly inhibited the migratory and invasive capacity of MDA-MB-231 cells at micromolar concentrations in a dose-dependent manner. • Adequate metabolic stability in vitro. EZH2 (enhancer of zeste homolog 2) is one of the most important histone methyltransferases (HMTs), and overexpression of EZH2 can lead to proliferation, migration and angiogenesis of tumor cells. But most of EZH2 inhibitors are only effective against some hematologic malignancies and have poor efficacy against solid tumors. Here, we report the design, synthesis, and evaluation of highly potent proteolysis targeting chimeric (PROTACs) small molecules targeting EZH2. We developed a potent and effective EZH2 degrader P4 , which effectively induced EZH2 protein degradation and inhibited breast cancer cell growth. Further studies showed that P4 can significantly decrease the degree of H3K27me3 in MDA-MB-231 cell line, induce apoptosis and G 0 /G 1 phase arrest in Pfeiffer and MDA-MB-231 cell lines. Therefore, P4 is a potential anticancer molecule for breast cancer treatment. [ABSTRACT FROM AUTHOR]

Here, four normalized difference water index (NDWI) variants, i.e., NDWI(860,970), NDWI(860,1240), NDWI(860,1640), and NDWI(1240,1640) are generated from the corn-oriented PROSAIL radiative transfer model. It is found that, instead of the linear relationship derived in previous studies, corn canopy water content (CWC) is best approximated as an exponential function of NDWI. Following the analysis of the PROSAIL-generated results, a newly optimized NDWI-based scheme is proposed for estimating corn CWC according to variations in the performance of the four NDWI variants under different CWC conditions. Validation results based on independent field data from the SMEX02, HiWATER2012, and Baoding2018 field experiments verify that this optimized NDWI-based corn CWC estimating scheme has a higher accuracy ($R = 0.87\,\,\pm \,\,0.03$ , RMSE = 0.2068 ± 0.0145 kg/m2) than existing NDWI-based strategies for corn CWC retrieval. The feasibility of retrieving corn vegetation water content (VWC) based on the optimized NDWI-based scheme is also investigated, and the superiority of the optimized NDWI-based scheme for retrieving corn VWC is assessed. By comparing with four other NDWI-based corn VWC estimating methods, as well as the corn VWC parameterization scheme applied in the SMAP soil moisture algorithm, it is shown that our optimized NDWI-based scheme has the best VWC estimation accuracy, with the highest $R$ of 0.89 ± 0.02 and the lowest RMSE of 0.7179 ± 0.0555 kg/m2. [ABSTRACT FROM AUTHOR]

Thrombospondin (TSP) 1 is a trimeric multidomain protein that contains motifs that recognize distinct host cell receptors coupled to multiple signaling pathways. Selected TSP1-induced cellular responses are tyrosine kinasedependent, and TSP! contains epidermal growth factor (EGF)-like repeats. Specific receptor interactions or functions for the EGF-like repeats have not been identified. We asked whether one or more biological responses to TSP! might be explained through EGF receptor (EGFR) activation. In A431 cells, TSP! increased autophosphorylation of Tyr1068 of EGFR in a doseand time-dependent manner. The ability of TSP1 to activate EGFR was replicated by the tandem EGF-like repeats as a recombinant protein. The three EGFlike repeats alone produced a high level of Tyr-1068 phosphorylation. EGF-like repeats from TSP2 and TSP4 also activated EGFR. Tyr-1068 phosphorylation was less when individual EGF-like repeats were tested or flanking sequences were added to the three EGF-like repeats. TSP1 and its EGF-like repeats also increased phosphorylation of EGFR Tyr-845, Tyr-992, Tyr-1045, Tyr-1086, and Tyr-1173, activated phospholipase Cγ, and increased cell migration. No evidence was found for binding of the EGF-like repeats to EGFR. Instead, EGFR activation in response to TSP1 or its EGF-like repeats required matrix metalloprotease activity, including activity of matrix metalloprotease 9. Access to the ligand-binding portion of the EGFR ectodomain was also required. These findings suggest release of an endogenous EGFR ligand in response to ligation of a second unknown receptor by the TSPs. [ABSTRACT FROM AUTHOR]

Gaseous pollutants transport inside liquid micro-cylinders with internal circulations in an equilateral triangular configuration is simulated to study the effects of varied gap-ratio (1 ≤ G / R ≤ 4), Reynolds (Re) number (30 ≤ Re ≤ 160) and incident angle (α = 0° , 30° and 60°) on the absorption in a uniform gaseous stream. The shear stress fluctuates with spatial position on the interface due to unsteady flow separation and attachment. Furthermore, the 'primary' and 'secondary' vortexes inside liquid micro-cylinders are induced, respectively, where soluble gaseous pollutants are quickly entrained and partially blocked into liquid micro-cylinders by 'inflow' and 'outflow' type circulations pair at the stern regions, respectively. For incident angles α = 0 ° and α = 60 ° , the symmetric flow forms because of the symmetric configuration of liquid micro-cylinders, while for incident angle α = 30 ° , the asymmetric flow appears due to asymmetric arrangement. The 'primary' (large clockwise) and 'secondary' (small counterclockwise) vortexes usually depending on Re number and G / R facilitate gaseous pollutants intrusion into liquid micro-cylinders at separation point. The sensitivity of gap-ratio is presented based on the transient accumulation (m so 2 ′), which characterizes the exact influence of G / R. The larger gap-ratio facilitates faster saturation of sulfur dioxide inside liquid micro-cylinders because of fully developed internal vortexes. As R e number increasing, the gaseous pollutants transport could be significantly enhanced because internal vortexes become gradually stronger. In addition, the incident angle has no significant effect on pollutants transport inside liquid micro-cylinders because of slightly direct interaction between separated shear layers and wakes. [ABSTRACT FROM AUTHOR]

• The stable cone-jet occurs in a certain range of electric potential and flow rate. • The electrified meniscus forms appears successively convex, linear sides and concave with an increase in electric potential. • The jet breakup transits from varicose to kink instability with an increase in flow rate. The cone-jet is one of the most interesting means in electrohydrodynamic atomization (EHDA) for wide applications because of highly charged and monodisperse drops. The pulsating and stable cone-jet modes in EHDA of diethyleneglycol (DEG) are observed by means of high-speed photography technology, as well as the breakup modes transition of electrified jet from varicose to kink instability. The conductive liquid is driven to form a liquid cone at the outlet of the capillary tube, and form a permanent jet from the apex of the cone by the tangential electric stress. With an increase in electric potential, the cone angle and jet length increase. The electrified meniscus and the cone may appear convex, linear sides and concave in cone jet regime, which depends on the static equilibrium of forces exists at each point of electrified liquid surface. The jet breakup modes with multi-jet, varicose and kink instabilities are successively recorded as liquid flow rates increasing. The jet breakup transition depends on flow rate. The drops size rises proportionally with an increase in liquid flow rate or a decrease in electric potential in stable cone-jet mode. The dimensionless diameter d / d 0 as a function of the dimensionless flow rate q V / q m is in good agreement with the universal scaling laws. [ABSTRACT FROM AUTHOR]

The environmental pollution caused by waste plastics and their potential of resource recovery are receiving increasing attention. In this study, a molecular level kinetic model was established to simulate the polypropylene pyrolysis based on the SOL method, Poisson distribution model and genetic algorithm, which was simplified and effective without the introduction of extensive chemical databases and stiff differential equations. The automatic generation of complex reaction network was based on the representation of species and reactions at molecular level and the design of 14 reaction rules consistent with the mechanism. The model prediction achieved good agreement with experimental data affected by the primary and secondary reactions, verifying the generalizability of the models. The model prediction according to the kinetic parameters provided guidance for the pyrolysis experiments. In general, the molecular-level model behaves exquisite in the evaluation, validation, and prediction, and can gain an insight into the pyrolysis of polymers. • A molecular level kinetic model with automatic reaction network generation is established for polypropylene pyrolysis. • The automatic network generation is based on the Poisson distribution model, the SOL method and the design of reaction rules. • This model achieves excellent agreement with experimental data and can predict pyrolysis performance in more details. • The important role of temperature on the pyrolysis and the competition of two scissions are quantified by this model. [ABSTRACT FROM AUTHOR]

Ultrathin ferromagnetic films display a wealth of spectacular characteristics, one of which is that two-dimensional ferromagnetism is stabilized exclusively by magnetic anisotropies. In this work, we experimentally demonstrated the realization of ultrathin yttrium iron garnet (Y3Fe5O12) films with perpendicular magnetic anisotropy by pulsed laser deposition. A labyrinthine magnetic domain configuration in Y3Fe5O12 was identified by magnetic force microscopy, qualitatively determining that the magnetic moment possesses an out-of-plane component. Magnetic moments in the Y3Fe5O12 film were investigated by using a vibrating sample magnetometer and magnetic circular dichroism spectroscopy. Due to the surface sensitivity, the characterization technique based on magnetic circular dichroism spectroscopy presents as a high-resolution magneto-optical method to determine the magnetic property quantitatively, which has an advantage over the vibrating sample magnetometer technique commonly used for bulk crystals or powders, especially when the paramagnetic background from the supporting substrate is non-negligible. Our work introduces the burgeoning material synthesis and processing technology, and miscellaneous characterization techniques into the study of conventional magnetic oxide films, providing powerful supplements to the detection and modulation of magnetism at the nanoscale. [ABSTRACT FROM AUTHOR]

[Display omitted] • The I 2 nanotraps were used by introducing adjacent IBSs and LBSs on the skeleton. • The absorbent shows high I 2 uptake capacity (37 wt%) among all COF materials. • IBSs and LBSs synergistically promote iodine adsorption. Covalent organic frameworks have been recognized as promising porous materials for the radioactive iodine capture. However, most COFs often suffer from low adsorption capacity under practical conditions (typically ≥ 150 °C, ≤ 150 ppmv I 2) due to the lack of strong binding sites and low affinity toward iodine, which restricts their application in industrial relevant conditions. Here, we develop a strategy of constructing highly efficient I 2 nanotraps by manipulating two kinds of adsorption sites (ionic binding sites and Lewis binding sites) located at adjacent spatial positions, thereby realizing the synergistic binding toward I 2. The obtained I 2 nanotrap 4F-iCOF-TpBpy-I- delivers a remarkable I 2 uptake capacity of 37 wt% at 150 °C and 150 ppmv of I 2 , which illustrate a record-high value for all COFs reported so far. This work opens a new avenue for the rational design of COF materials toward highly efficient I 2 capture and related application. [ABSTRACT FROM AUTHOR]

α-MgAgSb is considered as a potential near-room-temperature thermoelectric material in virtue of its excellent electrical properties, ultralow lattice thermal conductivity and abundant constituent elements. However, it is hard to obtain high-quality phase pure α-MgAgSb due to its complex phase transition and high reactivity of element Mg, which cloaks material's intrinsic thermoelectric performance. Herein, through adopting a tantalum-sealing melting technique, we achieved highly-quality pure α-MgAgSb with large grain size and less oxygen content, as compared with our ball milled samples. The as-synthesized tantalum-sealing melted α-MgAgSb, without element doping or alloying, exhibited intrinsically low thermal conductivity, large weighted mobility, and high carrier concentration closes to the optimum range. Eventually, we attained a maximum thermoelectric figure of merit zT value of 1.3 at around 500 K in the tantalum-sealing melted α-MgAgSb. The average power factors and average zT values are also as high as 25 μW cm−1 K−2 and 1.1 respectively in the low-temperature range of (300 - 550) K, both of which rank as top values among the known materials. This study not only sheds new light on the understanding of intrinsic properties of α-MgAgSb but also demonstrates its great promise for harvesting low-grade waste heat. Record-high average power factor of 25 μW cm−1 K−2 and average zT of 1.1 were achieved in the melted α-MgAgSb sythesized by the tantalum-sealing melting technique. [Display omitted] [ABSTRACT FROM AUTHOR]

Urban impervious surfaces area (ISA) and green space (GS), two primary components of urban environment, are pivotal in detecting urban environmental quality and addressing global environmental change issues. However, the current global mapping of ISA and GS is not effective enough to accurately delineate in urban areas due to the mosaicked and complex structure. To address the issue, the hierarchical architecture principle and subpixel metric method were applied to map 30 m global urban ISA and GS fractions for the years 2015 and circa 2020. We use random forest algorithms for retrieval of the Normalized Settlement Density Index and Normalized Green Space Index from Landsat images using Google Earth Engine. The correlation coefficients of global urban ISA and GS fractions were all higher than 0.9 for 2015 and circa 2020. Our results show global urban ISA and GS areas in circa 2020 were 31.19 × 104 km2 and 17.16 × 104 km2, respectively. The novel ISA and GS fractions product can show potential applications in assessing the effects of urbanization on climate, ecology, and urban sustainability. [ABSTRACT FROM AUTHOR]

• The droplet formation in electric periodic dripping regime was visualized. • The oscillation of electrified meniscus was visualized and identified. • The characteristic frequency deceases with an increase in applied potential. • The amplitude increases as electric number increasing. The dynamics of droplets and oscillation of electrified meniscus at low flow rates in an external electric field were investigated. An electric field is created by nozzle-plated electrode. The evolution of droplet formation is recorded by a high-speed digital camera. Meanwhile, the time evolution of meniscus is also focused. The critical sizes of the droplet and liquid thread were used to characterize the dynamics of droplet formation and oscillation of the meniscus. The results showed that a droplet gradually originates from a hemispherical meniscus and changes from spherical to pear-shaped. A liquid thread connects the meniscus and primary droplet, and pinches off as time advances. The droplets diameter decreases as electric potential increasing and is dependent of capillary diameter, while usually independent of flow rates. The droplet limiting length decreases, while the liquid thread diameter increases as electric Bond number increasing. The period of detachment decreases with an increase in electric potential and strongly depends on flow rate. The meniscus usually oscillates when the primary droplet detaches. The oscillation frequency increases as electric field strength increasing and is substantially affected by flow rate. An approximate equation to predict the oscillation frequency was presented, where the electric potential was taken into account. The variation of the oscillation frequency is qualitatively good agreement with experimental work. The amplitude of oscillation (or displacement) is significantly affected by electric field and increases as electric Bond number increasing. [ABSTRACT FROM AUTHOR]

• A new operational model with ant-miner algorithm was proposed to predict the risk of forest fires in cloud-rich areas. • The performance of proposed model was compared with that of the national risk prediction model of China. • The proposed model was compared to other risk prediction models with two classical machine learning algorithms. • The ant-miner algorithm-based model was more effective and reliable. Annually, millions of hectares of forest lands around the world are destroyed by fires. To minimize the fire-caused losses, more studies on the risk prediction of forest fires need to be carried out. For predicting the risk of forest fires in cloud-rich areas (e.g., the southwest of China), the synergetic use of operational forecasting systems and remote sensing-based models is expected to have a consistent performance. Therefore, we proposed in this study a new model based on ant-miner algorithm which has a good capability of solving multivariable and non-linear problems in the synergetic modeling of multi-source data. Based on historical fire data during 2000–2018 in Chongqing city, its performance was tested, and then was compared with that of other three models (i.e., meteorological data-, Artificial Neural Network-, and Support Vector Machine-based models). Results showed that, without interference from human factors, the risk predictions of proposed model were more objective. And, its mined-rules were easier to understand and also portable across multiple GIS platforms. Moreover, the proposed model has a better performance at predicting risk levels (i.e., overall accuracy was 79.02% and Kappa coefficient was 0.678) and the spatial distribution of its predictions were more detailed. This research indicated that the ant-miner algorithm-based model was more effective and reliable, and it could be used for constructing the operational system of risk predictions for forest fires in cloud-rich areas. [ABSTRACT FROM AUTHOR]

As a primary air pollutant, fine particulate matter (PM 2.5) is increasingly attracting attention. Crowdsourcing observations based methods are thought to be the best solutions for identifying the spatio-temporal distribution of PM 2.5 in intra-urban areas. However, inconsistent timing in the collection of crowdsourced data has typically been ignored in previous studies. To address this issue, a temporally calibrated method (TCM) was introduced in this study. By interpolating TCM-estimated observations using the inverse distance weighted (IDW) method, variations of PM 2.5 concentrations across the urban areas of Changsha City were captured. The results demonstrate that TCM can efficiently resolve the inconsistent timing defects of raw crowdsourcing observations (R 2 was 0.73 and the RMSE was 7.65 μg/m3). Furthermore, PM 2.5 distributions developed using TCM-based interpolations are of a finer spatial scale than those developed from raw observations at crowdsourcing locations. With a lack of funds to build sufficient stationary monitoring sites, developing crowdsourcing observation-based technology is the most promising solution for revealing intra-urban PM 2.5 variations at a higher spatio-temporal- resolution. Image 1 • A temporal calibration method was introduced for crowdsourcing air quality data. • TCM can eliminate time inconsistence of original crowdsourcing based PM 2.5 concentrations. • Intra-urban variations of PM 2.5 concentrations were revealed by densely observation. • Crowdsourcing observation is effective for fine scale air quality mapping in urban area. [ABSTRACT FROM AUTHOR]

In recent years, global forest fires have occurred more frequently, seriously destroying the structural functions of forest ecosystem. Mapping the burn severity after forest fires is of great significance for quantifying fire's effects on landscapes and establishing restoration measures. Generally, intensive field surveys across burned areas are required for the effective application of traditional methods. Unfortunately, this requirement could not be satisfied in most cases, since the field work demands a lot of personnel and funding. For mapping severity levels across burned areas without field survey data, a semi-supervised transfer component analysis-based support vector regression model (SSTCA-SVR) was proposed in this study to transfer knowledge trained from other burned areas with field survey data. Its performance was further evaluated in various eco-type regions of southwestern United States. Results show that SSTCA-SVR which was trained on source domain areas could effectively be transferred to a target domain area. Meanwhile, the SSTCA-SVR could maintain as much spectral information as possible to map burn severity. Its mapped results are more accurate (RMSE values were between 0.4833 and 0.6659) and finer, compared to those mapped by ∆NDVI-, ∆LST-, ∆NBR- (RMSE values ranged from 0.7362 to 1.1187) and SVR-based models (RMSE values varied from 1.7658 to 2.0055). This study has introduced a potentially efficient mechanism to map burn severity, which will speed up the response of post-fire management. [ABSTRACT FROM AUTHOR]

A novel electrochemical biosensing method that can take into account both immunoassay and enzyme activity analysis was reported in this work for determination of the enzymatically active human apurinic/apyrimidinic endonuclease 1 (APE1). The basic principle is to design and construct a DNA catalytic hairpin assembly (CHA) triggered by APE1 catalysis in enzyme activity analysis, and the assembled DNAs are labeled with electrochemically active CdS and PbS quantum dots to output electrochemical signals. In this system, the signal generation needs to satisfy both the conditions of immunological recognition and enzymatic catalysis, providing a basis for accurate analysis of active APE1. Results show that this method can reflect the regulation of the enzyme activity and can also distinguish APE1 from its isozymes with the same enzyme activity. The concept and successful implementation of this integrated system will contribute to the research and application of APE1 in biomedicine, and provide a reference for the accurate analysis of other enzymes. Image 1 • A novel electrochemical biosensing system is developed for the detection of APE1. • The strategy skillfully integrates immunoassay with enzyme activity analysis through an elaborate design. • The detection limit of APE1 biosensor is as low as 0.00518 U/mL. • The strategy can monitor the regulation of the enzyme activity by an inhibitor and discrimination of APE1 from its isozyme. [ABSTRACT FROM AUTHOR]