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Pt-based alumina catalysts doped with varying niobium contents (i.e., 0, 1.20, 2.84, and 4.73 wt%, denoted as Pt/Nb–Al2O3) were synthesized via stepwise impregnation for catalytic CO oxidation. The effective incorporation of Nb species without altering the fundamental properties of the Al2O3 support was confirmed by the characterization using XRD, Raman, and TEM. Pt metallic particles were uniformly deposited on the niobium-doped alumina (Nb–Al2O3) support. H2-TPR and CO–TPD analyses were performed to reveal the influence of niobium doping on catalyst reduction and CO adsorption properties. The results consistently demonstrate that the doping of niobium affects reducibility and alleviates the competitive adsorption between CO and O2 during the CO reaction. Particularly, when compared to both undoped and excessively doped Pt/Al2O3 catalysts, the catalyst featuring a 2.84 wt% Nb content on Pt1.4/Nb2.8–Al2O3 displayed the most promising catalytic performance, with a turnover frequency of 3.12 s−1 at 180 °C. This superior performance can be attributed to electron transfer at the Pt/NbOx interface. [ABSTRACT FROM AUTHOR]

In this paper, a new two-body self-synchronization vibration system characterized by two ideal vibration-exciting motors (asynchronous motors) installed on different vibrating bodies is investigated. Firstly, differential equations of the system are established via the Lagrange equation. Moreover, natural frequencies and stable solutions are obtained. Then, the conditions for the system to implement stable self-synchronization are derived using the equilibrium point theory of the dynamics system and Lyapunov's stability theory. The effects of spring stiffness on the natural frequencies and synchronous motion are numerically analyzed. The steady-state responses of the system are obtained for different structure parameters. The research results show that this system can implement two types of self-synchronization motion under different structure parameters. The first type fluctuates the phase differences in the proximity of zero rad, while the other one fluctuates the phase differences near π rad. Resonance significantly affects the synchronous motion of the system, rapidly changing in phase differences and amplitudes. An increase in the value of k y 2 is not conducive to implementing the stable synchronous motion. Finally, the correctness of the theory and electromechanical coupling simulation results is experimentally validated. The results of this paper can be directly used to determine the structural parameters for a new type of vibrating machine. [ABSTRACT FROM AUTHOR]

The use of warm-mix recycling technology can reduce the mixing temperature and the secondary aging of binders in reclaimed asphalt pavement (RAP), which is one of the effective ways to recycle high-content RAP. In this study, the penetration, softening point, ductility, and viscosity were used to characterize the conventional physical properties of aged asphalt after regenerating, while a dynamic shear rheometer (DSR), force ductility tester (FDT), and atomic force microscope (AFM) were used to evaluate the rheological performance and micro-morphology of aged asphalt incorporating a new bio-based warm-mix rejuvenator (BWR) and a commercial warm-mix rejuvenator (ZJ-WR). The regeneration mechanism of warm-mix rejuvenators on aged asphalt was analyzed by Fourier transform infrared spectroscopy (FTIR). The results show that the new bio-based warm-mix rejuvenator can restore the conventional physical properties, low-temperature performance, and micro-morphology of aged asphalt with an appropriate dosage, but it has a negative effect on high-temperature performance. In comparison with 2D area parameters, 3D roughness parameters were more accurate in evaluating the variation in micro-morphology of aged asphalt after regeneration. The FTIR analysis results indicate that both the new bio-based warm-mix rejuvenator and the commercial warm-mix rejuvenator regenerate aged asphalt by physical action, and AS=O and AC-H values are more reasonable than the AC=O value for the restoration evaluation of aged asphalt. And the new bio-based warm-mix rejuvenator has a better regeneration effect on the performance and micro-morphology of aged asphalt than the commercial warm-mix rejuvenator. [ABSTRACT FROM AUTHOR]

5-Methyluridine (5-MU) is a prominent intermediate for industrial synthesis of several antiviral-drugs, however, its availability over the past decades has overwhelmingly relied on chemical and enzymatic strategies. Here, we have realized efficient production of 5-MU in E. coli, for the first time, via a designer artificial pathway consisting of a two-enzyme cascade (UMP 5-methylase and phosphatase). More importantly, we have engineered the E. coli cell factory to boost 5-MU production by systematic evaluation of multiple strategies, and as a proof of concept, we have further developed an antibiotic-free fermentation strategy to realize 5-MU production (10.71 g/L) in E. coli MB229 (a ΔthyA strain). Remarkably, we have also established a versatile and robust platform with exploitation of the engineered E. coli for efficient production of diversified UMP-derived chemicals. This study paves the way for future engineering of E. coli as a synthetic biology platform for acceleratively accessing UMP-derived chemical diversities. • A designer artificial pathway comprising a two-enzyme cascade has been constructed for 5-MU biosynthesis. • 5-MU production has reached to 9.94 g/L in engineered E. coli with employing multiple synthetic biology strategies. • An antibiotic-free strategy has been developed for robust production of 5-MU (10.71 g/L) in the strain E. coli MB229. • A versatile E. coli platform has been further established for efficient production of diverse UMP-derived chemicals. [ABSTRACT FROM AUTHOR]

We propose a scheme for generating a five-photon hyperentangled spatial-polarization cluster state based on weak cross-Kerr nonlinearity. Using Bell state and three-photon GHZ state as the initial states, this hyperentangled state in two degrees of freedom is generated. The success probability of our scheme can reach 100% without considering experimental conditions. Additionally, we apply a simpler and deterministic controlled-NOT gate in our scheme. Finally, we discuss the error probability of X-homodyne detection and the feasibility of implementing the scheme. [ABSTRACT FROM AUTHOR]

In this paper, the synchronous motion characteristics of a two-rigid-body vibration system with three vibrating motors installed on two different vibrating rigid bodies are investigated. First, differential equations of the system are deduced according to the Lagrange equation, and their steady-state solutions are obtained. Next, the synchronization theories of the system are obtained via the average method, and the stability conditions are deduced via the Lyapunov's stability theory. The structural parameters of the system are brought into the theoretical derivation results. Finally, the theory and simulation are mutually verified by the electromechanical coupling simulation model. The results show that the system can implement stable synchronous motion when the system parameters satisfy the synchronization and stability conditions. In the resonance region (i.e., k y 2 = 100000 N / m , k y 1 ∈ [ 100000,2000000 ] N / m or k y 2 = 500000 N / m , k y 1 ∈ [ 100000,2000000 ] N / m ), the support spring stiffnesses k y 1 and k y 2 significantly affect the synchronous motion characteristics of the system. The phase differences 2 α 1 and 2 α 2 bifurcate in the regions R2, R5, and R6. However, the bifurcation phenomena have almost no effect on the steady-state responses. The parameters in the regions R3, R4, R7, and R8 are of great values in engineering applications. [ABSTRACT FROM AUTHOR]

Wireless sensor network (WSN) location is a significant research area. In complex environments like forests, inaccurate signal intensity ranging is a major challenge. To address this issue, this paper presents a reliable WSN distance measurement-positioning algorithm for forest environments. The algorithm divides the positioning area into several sub-regions based on the discrete coefficient of the collected signal strength. Then, using the fitting method based on the signal intensity value of each sub-region, the algorithm derives the reference points of the logarithmic distance path loss model and path loss index. Finally, the algorithm locates target nodes using anchor nodes in different regions. Additionally, to enhance the positioning accuracy, weight values are assigned to the positioning result based on the discrete coefficient of the signal intensity in each sub-region. Experimental results demonstrate that the proposed WSN algorithm has high precision in forest environments. [ABSTRACT FROM AUTHOR]

Gas bearing marine silt is widely distributed in China's offshore areas. The shear failure of gas bearing marine silt may lead to marine engineering geological disasters, such as seabed subsidence and submarine landslides. Monitoring the shear failure process of gassy soil in real time can warn marine geological disasters and ensure the safety of marine engineering. Marine resistivity monitoring has the advantages of a large monitoring range and real time measurement, so it has good application potential. However, the variations in resistivity during the shear failure of gas bearing marine silt are not clear. In this study, we obtained the resistivity changes of gas bearing marine silts during the shear failure process through triaxial experiments combined with resistivity measurements, and we analyzed the factors controlling the resistivity changes. The results show that the shear failure of gas bearing silt samples with different dry densities has stable resistivity characteristics. Moreover, for the two electrical factors in the process of soil shear failure, the evolution of soil cracks and the soil wettability, the change of resistivity is controlled by the change of soil wettability. The failure stage of shear failure can be identified by the change in the resistivity of gas bearing soil. [ABSTRACT FROM AUTHOR]

Ionic conductors (ICs) find widespread applications across different fields, such as smart electronic, ionotronic, sensor, biomedical, and energy harvesting/storage devices, and largely determine the function and performance of these devices. In the pursuit of developing ICs required for better performing and sustainable devices, cellulose appears as an attractive and promising building block due to its high abundance, renewability, striking mechanical strength, and other functional features. In this review, we provide a comprehensive summary regarding ICs fabricated from cellulose and cellulose-derived materials in terms of fundamental structural features of cellulose, the materials design and fabrication techniques for engineering, main properties and characterization, and diverse applications. Next, the potential of cellulose-based ICs to relieve the increasing concern about electronic waste within the frame of circularity and environmental sustainability and the future directions to be explored for advancing this field are discussed. Overall, we hope this review can provide a comprehensive summary and unique perspectives on the design and application of advanced cellulose-based ICs and thereby encourage the utilization of cellulosic materials toward sustainable devices. [ABSTRACT FROM AUTHOR]

Photoacoustic imaging (PAI), a state‐of‐the‐art noninvasive in vivo imaging technique, has been widely used in clinical disease diagnosis. However, the design of high‐performance PAI agents with three key characteristics, i.e. near‐infrared (NIR) absorption (λabs>800 nm), intense PA signals, and excellent photostability, remains a challenging goal. Herein, we present a facile but effective approach for engineering PAI agents by amplifying intramolecular low‐frequency vibrations and enhancing the push‐pull effect. As a demonstration of this blended approach, we constructed a PAI agent (BDP1‐NEt2) based on the boron‐dipyrromethene (BODIPY) scaffold. Compared with indocyanine green (ICG, an FDA‐approved organic dye widely utilized in PAI studies; λabs=788 nm), BDP1‐NEt2 exhibited a UV/Vis‐NIR spectrum peaked at 825 nm, superior in vivo PA signal intensity and outstanding stability to offer improved tumor diagnostics. We believe this work provides a promising strategy to develop the next generation of PAI agents. [ABSTRACT FROM AUTHOR]

Photoacoustic imaging (PAI), a state‐of‐the‐art noninvasive in vivo imaging technique, has been widely used in clinical disease diagnosis. However, the design of high‐performance PAI agents with three key characteristics, i.e. near‐infrared (NIR) absorption (λabs>800 nm), intense PA signals, and excellent photostability, remains a challenging goal. Herein, we present a facile but effective approach for engineering PAI agents by amplifying intramolecular low‐frequency vibrations and enhancing the push‐pull effect. As a demonstration of this blended approach, we constructed a PAI agent (BDP1‐NEt2) based on the boron‐dipyrromethene (BODIPY) scaffold. Compared with indocyanine green (ICG, an FDA‐approved organic dye widely utilized in PAI studies; λabs=788 nm), BDP1‐NEt2 exhibited a UV/Vis‐NIR spectrum peaked at 825 nm, superior in vivo PA signal intensity and outstanding stability to offer improved tumor diagnostics. We believe this work provides a promising strategy to develop the next generation of PAI agents. [ABSTRACT FROM AUTHOR]

Fingerprints are one of the distinguishing characteristics of an individual, remaining unaltered throughout one's lifetime. It should be noted that fingerprints are significant and reliable evidence in various cases, such as criminal investigations, medical diagnosis, and public security. Thus, it is necessary to develop efficient techniques for fingerprints detection. Fortunately, the fluorescence emission of aggregation‐induced emission (AIE) materials would increase instead of quenching upon excitation when they label fingerprints, which would clearly observe the structure of fingerprints. Herein, we devised a novel AIE‐active fluorophore (NI‐DB) with electron donor‐π bridge‐electron acceptor (D‐π‐A) structure based on the 1,8‐naphthalimide. To our delight, after fingerprints fixed by cyanoacrylate glue fuming, NI‐DB is capable of detecting and imaging fingerprints via its intrinsic fluorescence emission. And, with the aid of this technique, fingerprints on various object surfaces are successfully developed, suggesting the broad applicability. [ABSTRACT FROM AUTHOR]

Sustainable oil palm production is a key issue in global biodiversity conservation and sustainable development. As one of the world's major vegetable oil crops, oil palm has expanded exponentially to meet increased demand over the past decades. However, previous monitoring and assessments of oil palm plantations were hampered because of the lack of high-resolution annual maps at the global scale. We produced annual oil palm plantation maps in 4 major producer countries (Indonesia, Malaysia, Thailand and Papua New Guinea) in Asia-Pacific from 2007 to 2018 at 100-m resolution using advanced remote sensing techniques with Phased Array L-band Synthetic Aperture Radar (PALSAR) and Moderate Resolution Imaging Spectroradiometer (MODIS) data. We uncover the global patterns of oil palm expansion and find that global oil palm expansion has a very high degree of potential conflict with local biodiversity. Globally, 99.9% of oil palm plantations overlapped with Conservation Priority Zones (CPZs) and oil palm plantations encroached on 231 protected areas. We suggest to incorporate the related issues into the Post-2020 Global Biodiversity Framework. [ABSTRACT FROM AUTHOR]

In cancer genomics research, gene expressions provide clues to gene regulations implicating patients' risk of survival. Gene expressions, however, fluctuate due to noises arising internally and externally, making their use to infer gene associations, hence regulation mechanisms, problematic. Here, we develop a new regression approach to model gene association networks while considering uncertain biological noises. In a series of simulation experiments accounting for varying levels of biological noises, the new method was shown to be robust and perform better than conventional regression methods, as judged by a number of statistical measures on unbiasedness, consistency and accuracy. Application to infer gene associations in germinal-center B cells led to the discovery of a three-by-two regulatory motif gene expression and a three-gene prognostic signature for diffuse large B-cell lymphoma. [ABSTRACT FROM AUTHOR]

The use of satellite synthetic aperture radar (SAR) for moving target imaging has gained popularity recently. Researchers are focused on improving its imaging quality. To achieve high-quality and fast imaging, we have developed a dual-mode refocusing algorithm. We optimized the algorithm's target speed estimation and carried out data enhancement and quantization design for SAR image refocusing. The design is implemented on a Xilinx XC5VFX130T FPGA. The dual-mode image data are based on a slice size of 512 × 512 for slice mode and 256 × 256 for scan mode in a time-series function simulation. The serial–parallel conversion and pipeline design balances the operating speed and logic resources for optimal performance. Experiment results on slice data of real SAR images show that the system's processing speed can reach two frames per second, utilizing 69633 LUTs, 255 RAMs, and 296 DSPs. [ABSTRACT FROM AUTHOR]

The assessment and prediction of the toxicity of engineered nanomaterials (NMs) present in mixtures is a challenging research issue. Herein, the toxicity of three advanced two-dimensional nanomaterials (TDNMs), in combination with an organic chemical (3,4-dichloroaniline, DCA) to two freshwater microalgae (Scenedesmus obliquus and Chlorella pyrenoidosa), was assessed and predicted not only from classical mixture theory but also from structure-activity relationships. The TDNMs included two layered double hydroxides (Mg-Al-LDH and Zn-Al-LDH) and a graphene nanoplatelet (GNP). The toxicity of DCA varied with the type and concentration of TDNMs, as well as the species. The combination of DCA and TDNMs exhibited additive, antagonistic, and synergistic effects. There is a linear relationship between the different levels (10, 50, and 90%) of effect concentrations and a Freundlich adsorption coefficient (KF) calculated by isotherm models and adsorption energy (Ea) obtained in molecular simulations, respectively. The prediction model incorporating both parameters KF and Ea had a higher predictive power for the combined toxicity than the classical mixture model. Our findings provide new insights for the development of strategies aimed at evaluating the ecotoxicological risk of NMs towards combined pollution situations. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to describe the clinical features of AAV and identify possible risk factors for end-stage renal disease (ESRD) and mortality in AAV based on the experience of a single center in China. Methods: A prospective cohort study of AAV was conducted based on data acquired by the Chinese Rheumatism Data Center (CRDC). The cohort involved 140 patients diagnosed with AAV in the Second Affiliated Hospital of Nanchang University from January 2013 to April 2022. Clinical characteristics and prognostic data were prospectively collected. The patients were divided into an ESRD group and a non-ESRD group, a death group and a survival group, Then, univariate and multivariate COX regression models were used to determine the risk factors associated with ESRD and mortality by AAV. Results: Multivariate Cox regression results showed that high initial serum creatinine (hazard ratio (HR) = 1.001, 95% confidence interval (CI): 1.000–1.002, P = 0.024), high initial Birmingham vasculitis activity score (BVAS) (HR = 1.081, 95% CI: 1.027–1.138, P = 0.003), and the need for dialysis treatment (HR = 4.918, 95% CI: 1.727–14.000, P = 0.003) were independent risk factors for the progression of ESRD in AAV patients. Multivariate Cox regression results showed that alveolar hemorrhage (HR = 3.846, 95% CI: 1.235–11.973, P = 0.020), interstitial lung disease (HR = 4.818, 95% CI: 1.788–12.982, P = 0.002), and low initial estimated glomerular filtration rate (EGFR) (HR = 0.981, 95% CI: 0.968–0.995, P = 0.009) were independent risk factors for the prediction of death in AAV patients. Conclusion: These findings suggest that high initial serum creatinine, a high initial BVAS score, and the need for dialysis were independent risk factors for the progression of ESRD in AAV patients. Alveolar hemorrhage, interstitial lung disease, and low initial EGFR were independent risk factors for death. Key Points • The risk factors for ESRD in AAV determined in this study are high initial serum creatinine, a high initial BVAS score, and the need for dialysis. • The risk factors for mortality in AAV are alveolar hemorrhage, interstitial lung disease, and low initial EGFR. [ABSTRACT FROM AUTHOR]

In the process of offshore exploitation, marine geological disasters such as seabed subsidence and submarine landslide threaten the service safety of offshore structures. The generation and development of shear zones in marine soil are the early characteristics of these marine geological disasters. Monitoring the dynamic change of shear zone volume fraction in marine soil in real time can reflect the instability of marine soil and then warn the geological disasters in the process of marine development. Marine resistivity monitoring has the advantages of a large monitoring range and real-time measurement, so it has good application potential. However, for the generation and development of shear zone in marine soil under load, the corresponding variation characteristics and the quantitative evaluation method of marine soil resistivity on this process are not clear at present. In this study, the remolded marine soil samples were configured based on the in situ sampling results of Hangzhou Bay, carried out resistivity triaxial compression experiments on marine soil samples with different dry density and clay content, and obtained the resistivity monitoring data of shear zone evolution process of different marine soil samples under vertical load. The results show that the resistivity change of marine soil with different dry density and clay content under vertical load is controlled by the volume fraction evolution of soil shear zone and has similar characteristics. Moreover, a method for quantitatively interpreting the volume fraction change of shear zone from resistivity monitoring data is proposed. [ABSTRACT FROM AUTHOR]

Remote sensing and land resource surveys have been used in recent decades for land use/land cover (LULC) mapping; however, keeping the developed LULC up-to-date and consistent with land survey statistics remains challenging. This study developed a practical and effective framework to automatically update existing LULC products and bridge the gap between remote sensing classification results and land survey data. This study employed Landsat imagery time series, change detection algorithms, sample migration, and random forests to develop a framework for updating existing LULC products in China from 1980–2015 to 1980–2022. The updated LULC maps reflect the post-2015 LULC changes well and maintain continuity with the pre-2015 products. Additionally, a statistical space allocation method based on the minimum cross-entropy strategy was proposed to optimize the LULC maps, increasing the correlation coefficient (r) with China's second and third national land survey statistics from 0.41–0.89 to 0.86–0.99. Thus, the framework and products developed in this study provide valuable tools for sustainable land use and policy planning. [ABSTRACT FROM AUTHOR]

Simple Summary: Ewing sarcoma is a malignant pediatric bone cancer currently lacking targeted therapy. In the US there are ~200 patients diagnosed each year and relapse is associated with resistance to the standard-of-care chemotherapy. Thus, it remains an urgent unmet medical need to develop effective new cures for Ewing sarcoma. It is well-characterized that Ewing sarcoma is largely driven by unique gene fusions, with EWSR1-FLI1 being the most prevalent. In this review, we summarize up-to-date regulatory mechanisms for the onco-fusion protein EWSR1-FLI1 in Ewing sarcoma, including both post-transcriptional and post-translational modifications, to reveal knowledge gaps and propose potential new therapeutic directions. Ewing sarcoma is the second most common bone tumor in childhood and adolescence. Currently, first-line therapy includes multidrug chemotherapy with surgery and/or radiation. Although most patients initially respond to chemotherapy, recurrent tumors become treatment refractory. Pathologically, Ewing sarcoma consists of small round basophilic cells with prominent nuclei marked by expression of surface protein CD99. Genetically, Ewing sarcoma is driven by a fusion oncoprotein that results from one of a small number of chromosomal translocations composed of a FET gene and a gene encoding an ETS family transcription factor, with ~85% of tumors expressing the EWSR1::FLI1 fusion. EWSR1::FLI1 regulates transcription, splicing, genome instability and other cellular functions. Although a tumor-specific target, EWSR1::FLI1-targeted therapy has yet to be developed, largely due to insufficient understanding of EWSR1::FLI1 upstream and downstream signaling, and the challenges in targeting transcription factors with small molecules. In this review, we summarize the contemporary molecular understanding of Ewing sarcoma, and the post-transcriptional and post-translational regulatory mechanisms that control EWSR1::FLI1 function. [ABSTRACT FROM AUTHOR]

Incidents in the use of lithium‐ion batteries are usually caused by the malfunction of flammable organic liquid electrolytes with poor thermal stability. Therefore, the development of noncombustible electrolytes is regarded as one of the most effective means to prevent the safety hazards of lithium‐ion batteries. Ionic liquids have attracted much interest recently, mainly due to their high ionic conductivity, low volatility, and incombustibility. The application of ionic liquids to the preparation of quasi‐solid‐state gel electrolytes combines the advantages of ionic liquids and avoids the risks of organic liquid electrolytes. Therefore, the solid‐state ionogels have been considered as a promising alternative electrolyte system, especially for the much‐desired energy storage devices with higher energy density and flexibility. This review focuses on the recent progress of ionogel electrolytes for lithium‐ion batteries. The preparation strategies for ionogel electrolytes based on different frameworks, namely inorganic matrix, organic matrix, and organic‐inorganic hybrid matrix, are discussed. Subsequently, efforts to improve the properties of the ionogel electrolytes, including the ionic conductivity, mechanical properties, and lithium‐ion transfer number, are summarized. Besides, the applications of ionogel electrolytes in high‐voltage lithium‐ion batteries and lithium metal batteries as well as the batteries under extreme environments are outlined. Finally, the perspectives on studying and improving the performances of ionogel electrolytes for advanced lithium‐ion batteries are provided. [ABSTRACT FROM AUTHOR]

Cancer is the second leading cause of human death globally. PI3K/Akt/mTOR signaling is one of the most frequently dysregulated signaling pathways observed in cancer patients that plays crucial roles in promoting tumor initiation, progression and therapy responses. This is largely due to that PI3K/Akt/mTOR signaling is indispensable for many cellular biological processes, including cell growth, metastasis, survival, metabolism, and others. As such, small molecule inhibitors targeting major kinase components of the PI3K/Akt/mTOR signaling pathway have drawn extensive attention and been developed and evaluated in preclinical models and clinical trials. Targeting a single kinase component within this signaling usually causes growth arrest rather than apoptosis associated with toxicity-induced adverse effects in patients. Combination therapies including PI3K/Akt/mTOR inhibitors show improved patient response and clinical outcome, albeit developed resistance has been reported. In this review, we focus on revealing the mechanisms leading to the hyperactivation of PI3K/Akt/mTOR signaling in cancer and summarizing efforts for developing PI3K/Akt/mTOR inhibitors as either mono-therapy or combination therapy in different cancer settings. We hope that this review will facilitate further understanding of the regulatory mechanisms governing dysregulation of PI3K/Akt/mTOR oncogenic signaling in cancer and provide insights into possible future directions for targeted therapeutic regimen for cancer treatment, by developing new agents, drug delivery systems, or combination regimen to target the PI3K/Akt/mTOR signaling pathway. This information will also provide effective patient stratification strategy to improve the patient response and clinical outcome for cancer patients with deregulated PI3K/Akt/mTOR signaling. [ABSTRACT FROM AUTHOR]

Peroxynitrite (ONOO−) plays a critical role in Alzheimer's disease (AD). To reveal the ONOO− influx in AD brains, an activatable activity‐based fluorescence probe Rd‐DPA3 was designed by a structure‐modulated strategy. Taking advantage of ONOO−‐initiated two‐step cascade reactions of a novel chemical trigger, Rd‐DPA3 specifically responds to ONOO− in 0.3 mM of other reactive oxygen species (ROS) and varied proteins, and gives an intensive fluorescence enhancement (F/F0=50). Moreover, with its mitochondria‐targeting ability, Rd‐DPA3 can be used to efficiently monitor the alternations of intracellular ONOO− levels in cerebral cells during oxidative stress. Significantly, due to NIR emission and good blood–brain barrier (BBB) crossing ability, Rd‐DPA3 is suitable for in vivo imaging of cerebral ONOO− influx and illustrating an age‐dependent accumulation of ONOO− in AD mice brains. [ABSTRACT FROM AUTHOR]

Peroxynitrite (ONOO−) plays a critical role in Alzheimer's disease (AD). To reveal the ONOO− influx in AD brains, an activatable activity‐based fluorescence probe Rd‐DPA3 was designed by a structure‐modulated strategy. Taking advantage of ONOO−‐initiated two‐step cascade reactions of a novel chemical trigger, Rd‐DPA3 specifically responds to ONOO− in 0.3 mM of other reactive oxygen species (ROS) and varied proteins, and gives an intensive fluorescence enhancement (F/F0=50). Moreover, with its mitochondria‐targeting ability, Rd‐DPA3 can be used to efficiently monitor the alternations of intracellular ONOO− levels in cerebral cells during oxidative stress. Significantly, due to NIR emission and good blood–brain barrier (BBB) crossing ability, Rd‐DPA3 is suitable for in vivo imaging of cerebral ONOO− influx and illustrating an age‐dependent accumulation of ONOO− in AD mice brains. [ABSTRACT FROM AUTHOR]

The complex morphological structure of Aspergillus niger influences its production of proteins, metabolites, etc., making the genetic manipulation and clonal purification of this species increasingly difficult, especially in aconidial Aspergillus niger. In this study, we found that N-acetyl-D-glucosamine (GlcNAc) could induce the formation of spore-like propagules in the aconidial Aspergillus niger SH2 strain. The spore-like propagules possessed life activities such as drug resistance, genetic transformation, and germination. Transcriptomic analysis indicated that the spore-like propagules were resting conidia entering dormancy and becoming more tolerant to environmental stresses. The Dac1 gene and the metabolic pathway of GlcNAc converted to glycolysis are related to the formation of the spore-like propagules, as evidenced by the CRISPRi system, qPCR, and semi-quantitative RT-PCR. Moreover, a method based on the CRISPR-Cas9 tool to rapidly recycle screening tags and recover genes was suitable for Aspergillus niger SH2. To sum up, this suggests that the spore-like propagules are resting conidia and the mechanism of their formation is the metabolic pathway of GlcNAc converted to glycolysis, particularly the Dac1 gene. This study can improve our understanding of the critical factors involved in mechanisms of phenotypic change and provides a good model for researching phenotypic change in filamentous fungi. [ABSTRACT FROM AUTHOR]

Glucoamylase has a wide range of applications in the production of glucose, antibiotics, amino acids, and other fermentation industries. Fungal glucoamylase, in particular, has attracted much attention because of its wide application in different industries, among which Aspergillus niger is the most popular strain producing glucoamylase. The low availability of NADPH was found to be one of the limiting factors for the overproduction of glucoamylase. In this study, 3 NADH kinases (AN03, AN14 , and AN17) and malic enzyme (maeA) were overexpressed in aconidial A. niger by CRISPR/Cas9 technology, significantly increasing the size of the NADPH pool, resulting in the activity of glucoamylase was improved by about 70%, 50%, 90%, and 70%, respectively; the total secreted protein was increased by about 25%, 22%, 52%, and 26%, respectively. Furthermore, the combination of the mitochondrial NADH kinase (AN17) and the malic enzyme (maeA) increased glucoamylase activity by a further 19%. This study provided an effective strategy for enhancing glucoamylase production of A. niger. [ABSTRACT FROM AUTHOR]

Approximately 40% of limited-stage (stage I and II) diffuse large B-cell lymphoma (LS-DLBCL) presents with extranodal disease. Extranodal LS-DLBCL may have significant biological differences and associated with worse outcomes than nodal disease. Although rituximab based chemoimmunotherapy is standard of first-line treatment, the role of consolidative radiotherapy (RT) in this particular subgroup is controversial. In this multicenter retrospective study, we evaluated the survival benefit of consolidative RT in patients diagnosed with extranodal LS-DLBCL and received rituximab-based chemoimmunotherapy with or without consolidative RT. A total of 328 patients were included, 129 patients (39.3%) received chemoimmunotherapy and consolidative RT, and 199 patients (60.7%) received chemoimmunotherapy alone. With a median follow-up of 5.1 years (range, 0.3–14.8 years), 5-year progression-free survival (PFS) and overall survival (OS) for all patients were 75.4% and 83.9%, respectively. In multivariate analyses, the addition of consolidative RT was associated with superior OS (P = 0.004) and PFS (P = 0.005). High stage-modified International Prognosis Index (SM-IPI) risk predicted worse OS (P = 0.001) and PFS (P = 0.005). Also, propensity score-matched analyses showed RT improved both OS (hazard ratio [HR] 0.228, 95% confidence index [CI] 0.111–0.467, P < 0.001) and PFS (HR 0.308, 95% CI 0.167–0.566, P < 0.001). Among patients who achieved CR, 49 patients (16.6%) developed disease relapse, of which 30.6% relapsed at local sites. Consolidative RT significantly reduced relapse risk (P = 0.002). Our results demonstrated that consolidative RT significantly improved outcomes in patients with extranodal LS-DLBCL in the rituximab era. [ABSTRACT FROM AUTHOR]

China has launched a series of ambitious poverty alleviation strategies to end extreme poverty, officially announcing the achievement of this goal in 2020. Currently, these counties persist in their efforts to achieve the goal of rural revitalization. Many studies often showcase the spatial patterns of China's remarkable success in counties out of poverty, but often disregard the relative poverty-returning risk (PRR), specifically within China's 832 extreme poverty counties. Nighttime light datasets (NTL) have been extensively employed as a surrogate measure for socioeconomic performance in underserved regions. In this work, we constructed an NTL-based relative PRR index to detect the spatial patterns of PRR among 832 counties. Then, we identified the main influencing factors concerning the PRR mitigation of 14 poverty-stricken clusters based on three dimensions: geophysical, economic, and social. Our results showed that counties in central China are far from returning to extreme poverty with low PRR. However 14 counties (2.41% of the 832) show high PRR, and those counties are mainly clustered in southwest China. This implies that those regions require more poverty-related policy support, financial inflows, and assistance. Regional differences were found in the factors that influence the mitigation of PRR. This is crucial for developing targeted strategies to consolidate poverty eradication. Our findings are essential for China's poverty-related SDGs, ensuring that no one is left behind. [Display omitted] • We investigated the 832 county-level relative PRRs. • China's relative PRRs are spatially imbalanced at the county level. • High PRR counties (2.41%) clusters gathering in southwestern China were observed. • There are geographic discrepancies in the factors that alleviate PRR. [ABSTRACT FROM AUTHOR]

High-quality cutaneous wound healing is associated with rapid wound closure and a comfortable healing process. Currently, exosomes derived from mesenchymal stem cells displayed a prominent therapeutic effect on skin wound closure. But the therapeutic approaches for wound itching are very limited in clinical. Stem cells from human exfoliated deciduous teeth (SHED) may offer a unique exosome resource for cell-free therapeutics in potential clinical applications. Here, we investigated the common mechanisms underlying wound closure and unpleasant sensation of itching, focusing on the contribution of the SHED-derived exosome to immune response and wound itching during healing. The effects of SHED-derived exosomes on inflammatory wound healing were examined using lipopolysaccharide (LPS)-induced wounds in a mouse model. We found prolonged inflammation and distinct itch responses in skin wound tissue during LPS-induced wound healing. SHED-derived exosomes facilitated LPS-induced wound closure and relieved wound itching. Therefore, they are ideal for the treatment of wound healing. Macrophages in skin wound tissues are responsible for autophagy during wound healing. Macrophage autophagy also regulates cell proliferation, migration, and neuronal signal transduction in vitro. SHED-derived exosomes containing miR-1246 enhanced autophagy by regulating macrophage function through the AKT, ERK1/2, and STAT3 signaling pathways. Thus, SHED-derived exosomes promote wound healing with less itching in an LPS-induced wound model by stimulating macrophage autophagy, which has implications for the treatment of inflammatory wound healing. [ABSTRACT FROM AUTHOR]

Glucoamylase has a wide range of applications in the production of glucose, antibiotics, amino acids, and other fermentation industries. Fungal glucoamylase, in particular, has attracted much attention because of its wide application in different industries, among which Aspergillus niger is the most popular strain producing glucoamylase. The low availability of NADPH was found to be one of the limiting factors for the overproduction of glucoamylase. In this study, 3 NADH kinases (AN03, AN14 , and AN17) and malic enzyme (maeA) were overexpressed in aconidial A. niger by CRISPR/Cas9 technology, significantly increasing the size of the NADPH pool, resulting in the activity of glucoamylase was improved by about 70%, 50%, 90%, and 70%, respectively; the total secreted protein was increased by about 25%, 22%, 52%, and 26%, respectively. Furthermore, the combination of the mitochondrial NADH kinase (AN17) and the malic enzyme (maeA) increased glucoamylase activity by a further 19%. This study provided an effective strategy for enhancing glucoamylase production of A. niger. [ABSTRACT FROM AUTHOR]

As satellite observation technology develops and the number of Earth observation (EO) satellites increases, satellite observations have become essential to developments in the understanding of the Earth and its environment. However, the current impacts to the remote sensing community of different EO satellite data and possible future trends of EO satellite data applications have not been systematically examined. In this paper, we review the impacts of and future trends in the use of EO satellite data based on an analysis of data from 15 EO satellites whose data are widely used. Articles that reference EO satellite missions included in the Web of Science core collection for 2020 were analyzed using scientometric analysis and meta-analysis. We found the following: (1) the number of publications and citations referencing EO satellites is increasing exponentially; however, the number of articles referencing AVHRR, SPOT, and TerraSAR is tending to decrease; (2) papers related to EO satellites are concentrated in a small number of journals: 43.79% of the articles that were reviewed were published in only 13 journals; and (3) remote sensing impact factor (RSIF), a new impact index, was constructed to measure the impacts of EO satellites and to predict future trends in applications of their data. Landsat, Sentinel, MODIS, Gaofen, and WorldView were found to be the most significant current EO satellite missions and MODIS data to have the widest range of applications. Over the next five years (2021–2025), it is expected that Sentinel will become the satellite mission with the greatest influence. [ABSTRACT FROM AUTHOR]

Monolithic ionogel electrolyte membranes (IGEMs) based on gelling scaffolds and ionic liquids have aroused intensive interest because of their broad processing compatibility, nonflammability, and favorable thermal and electrochemical features. However, the absence of functional scaffolds that concurrently enable high mechanical strength and Li+ transportability of IGEMs constrains the battery power and safety. Herein, a task‐specific IGEM monolith featuring high Li+ conductivity and outstanding thermal stability is demonstrated, whereby electrospun positively charged poly(ionic liquid) nanofibers serve as a thermotolerant scaffold for the IGEM. Regulating the Li+ environment in the IGEM enables the shift from the sluggish vehicular to fast structural Li‐ion transport mode. With the unique IGEM, the solid‐state Li||LiFePO4 cells achieve improved rate capability and good cyclability in a wide temperature range from 0 to 90 °C. Furthermore, practical solid‐state Li||LiFePO4 pouch cells with a cathode capacity of ≈2 mAh cm−2 have also been demonstrated. [ABSTRACT FROM AUTHOR]

Given the increasingly severe challenges of global climate change and sustainable development, accurate prediction of daily carbon dioxide (CO 2) emissions has become crucial. However, current research on real-time daily forecasts remains relatively scarce, often limited to annual predictions and point estimates. This paper proposes an innovative integrated model, based on quantile regression and Attention-Bidirectional Long Short-Term Memory (BILSTM), specifically designed for probabilistic prediction of daily carbon emissions. Testing the model on daily carbon emission data from major carbon-emitting countries including China, the United States, India, Russia, and Italy has demonstrated its superior performance across various metrics, including mean squared error (MSE), mean absolute error (MAE), coefficient of determination (R2), and normalized average width of prediction intervals (PINAW), compared to other benchmark models. This achievement not only highlights the model's effectiveness in predicting daily carbon emissions but also provides policymakers with a powerful tool for real-time monitoring and assessment of carbon emissions. Furthermore , the application of probabilistic forecasting methods enables decision-makers to gain a more comprehensive understanding of the potential range of future carbon emissions, providing strong support for the formulation of targeted policies. [ABSTRACT FROM AUTHOR]

• We developed a multiethnic Asian Macronutrient and Taste Preference Ranking Task. • The task was designed for large-scale electronic data collection using smartphones. • We validated the task using randomised crossover administration of standard meals. • The task scores correlated well with self-reported macronutrient intakes. Understanding how changes in individual food preferences in a dynamic environment translate into dietary choices helps to unravel the aetiology of suboptimal nutrition in the population. To facilitate the measurements of food preferences in a multiethnic Asian population, we aimed to develop and validate the Macronutrient and Taste Preference Ranking Task (MTPRT) in an Asian population. We shortlisted 1770 local food items based on the predominant macronutrient groups (≥50 % macronutrient content is protein or fat or carbohydrates), classified their taste clusters, standard-photographed a final list of 36 food items, and developed an electronic survey through cognitive interviews with 30 participants. We then validated the MTPRT amongst 66 participants (mean (SD) age = 47.4 (11.7) years, 57.6 % male, with Chinese: Malay: Indian ethnicity ratio 3:1:1), through random crossover administration of sweet and savoury standard meals with equivalent macronutrients across 2 study visits over a week. The average duration taken to complete MTPRT was 14.1 (5.3) minutes. The sweet and savoury taste preference scores were inversely correlated (r = -0.9, p < 0.0001). The liking and preference for savoury taste were reduced after consuming savoury meals (p = 0.0009). The intra-person correlations for MTPRT scores were all r > 0.6, p < 0.001. The macronutrient preference scores were all positively associated with the self-reported macronutrient intakes derived from the Food Frequency Questionnaire, independent of sex, age, ethnicity, and BMI. Our study demonstrates the validity and reproducibility of MTPRT in multiethnic Asian populations for future evaluation of food preferences in multiethnic Asian population. [ABSTRACT FROM AUTHOR]

Greenspaces on university campuses have gained recognition for their multifaceted impact on the physical, social, emotional and intellectual well‐being of students. The allocation of resources towards the development and maintenance of greenspaces is regarded as a strategy in the pursuit of sustainable development goals. However, the research on greenspaces within higher education has been inadequate. This study conducts an assessment of greenspaces within 2556 Chinese universities using remote sensing and geospatial technology, analysing the disparities in their distribution and exploring the spatial patterns and driving factors on a national scale. A national university greenspace database is obtained. Unexpectedly, the study finds that greenspace area and proportion within Chinese universities are relatively low in comparison to the greenspace areas outside the campus and of the city. There is heterogeneity and a decreasing trend in university greenspace. Compared to university faculty and off‐campus population, university students have the lowest per capita greenspace area. Of concern is the significant issue of greenspace inequality. Our research suggests that the inequality in greenspace provision for university students can be explained by factors of economic development, educational investments and provincial greenspace supply. This study provides an in‐depth analysis of the state of greenspaces in Chinese universities and calls for interdisciplinary and interdepartmental cooperation to address issues of greenspace inequality and campus greening, ensuring the sustainability and livability of urban areas and university campuses. [ABSTRACT FROM AUTHOR]

Rechargeable batteries, typically represented by lithium-ion batteries, have taken a huge leap in energy density over the last two decades. However, they still face material/chemical challenges in ensuring safety and long service life at temperatures beyond the optimum range, primarily due to the chemical/electrochemical instabilities of conventional liquid electrolytes against aggressive electrode reactions and temperature variation. In this regard, a gel polymer electrolyte (GPE) with its liquid components immobilized and stabilized by a solid matrix, capable of retaining almost all the advantageous natures of the liquid electrolytes and circumventing the interfacial issues that exist in the all-solid-state electrolytes, is of great significance to realize rechargeable batteries with extended working temperature range. We begin this review with the main challenges faced in the development of GPEs, based on extensive literature research and our practical experience. Then, a significant section is dedicated to the requirements and design principles of GPEs for wide-temperature applications, with special attention paid to the feasibility, cost, and environmental impact. Next, the research progress of GPEs is thoroughly reviewed according to the strategies applied. In the end, we outline some prospects of GPEs related to innovations in material sciences, advanced characterizations, artificial intelligence, and environmental impact analysis, hoping to spark new research activities that ultimately bring us a step closer to realizing wide-temperature rechargeable batteries. [ABSTRACT FROM AUTHOR]

Organic small‐molecule fluorophores, characterized by flexible chemical structure and adjustable optical performance, have shown tremendous potential in biosensing. However, classical organic fluorophore motifs feature large overlap between excitation and emission spectra, leading to the requirement of advanced optical set up to filter desired signal, which limits their application in scenarios with simple settings. Here, a series of wavelength‐tunable small‐molecule fluorescent dyes (PTs) bearing simple organic moieties have been developed, which exhibit Stokes shift up to 262 nm, molar extinction coefficients ranged 30,000–100,000 M−1 cm−1, with quantum yields up to 54.8 %. Furthermore, these dyes were formulated into fluorescent nanoparticles (PT‐NPs), and applied in lateral flow assay (LFA). Consequently, limit of detection for SARS‐CoV‐2 nucleocapsid protein reached 20 fM with naked eye, a 100‐fold improvement in sensitivity compared to the pM detection level for colloidal gold‐based LFA. Besides, combined with loop‐mediated isothermal amplification (LAMP), the LFA system achieved the visualization of single copy level nucleic acid detection for monkeypox (Mpox). [ABSTRACT FROM AUTHOR]

Organic small‐molecule fluorophores, characterized by flexible chemical structure and adjustable optical performance, have shown tremendous potential in biosensing. However, classical organic fluorophore motifs feature large overlap between excitation and emission spectra, leading to the requirement of advanced optical set up to filter desired signal, which limits their application in scenarios with simple settings. Here, a series of wavelength‐tunable small‐molecule fluorescent dyes (PTs) bearing simple organic moieties have been developed, which exhibit Stokes shift up to 262 nm, molar extinction coefficients ranged 30,000–100,000 M−1 cm−1, with quantum yields up to 54.8 %. Furthermore, these dyes were formulated into fluorescent nanoparticles (PT‐NPs), and applied in lateral flow assay (LFA). Consequently, limit of detection for SARS‐CoV‐2 nucleocapsid protein reached 20 fM with naked eye, a 100‐fold improvement in sensitivity compared to the pM detection level for colloidal gold‐based LFA. Besides, combined with loop‐mediated isothermal amplification (LAMP), the LFA system achieved the visualization of single copy level nucleic acid detection for monkeypox (Mpox). [ABSTRACT FROM AUTHOR]

[Display omitted] • A slight decrease in the total carbon stock of China's Loess Plateau (CLP) occurred from 1980 to 2019. • The total carbon density gain rate in wildlands was accelerating. • The carbon stock dynamics in the CLP over the past 40 years were primarily influenced by socioeconomic variables with a total relative importance of 84.30 %. • The diverse responses of carbon dynamics to the drivers in space were revealed. Synergies and trade-offs among land use and land covers (LULCs) pose considerable uncertainties in achieving the dual carbon goals for China's Loess Plateau (CLP). In this context, we unraveled the carbon stock dynamics induced by land use and land cover change (LUCC) in the CLP over the past 40 years using the satellite-derived annual LULC maps and the InVEST model. Then, mixed measures were employed to quantify the global and local responses of the carbon stock dynamics to both natural and anthropogenic factors. We found that approximately a total of 5.58 × 109 Mg of carbon was stored in the CLP's ecosystems in 2019. Chronologically, the total carbon stock showed a slight decrease in the CLP from 1980 to 2019 due to the extensive LUCCs linked to socioeconomic activities. Specifically, the total carbon density loss rate accelerated in urban–rural-wild continuum (RUWC) types with higher human activity intensity, such as villages and urban, while it decelerated in woodlands, and croplands, where the human activity intensity is lower. Moreover, the total carbon density gain rate in wildlands was accelerating. Finally, we revealed that the carbon stock dynamics in the CLP over the past 40 years were primarily influenced by socioeconomic variables and have responded diversely to the drivers in space. [ABSTRACT FROM AUTHOR]

• An optical structure of liquid crystal lens based on integrated composite electrodes with excellent performance is proposed. • Comprehensive simulations of liquid crystal lens based on integrated composite electrodes in the structure and performance are conducted. A large aperture liquid crystal (LC) lens array based on integrated composite electrodes (ICE-LC) lens array with low operating voltages is proposed. The top substrate contains composite electrodes, while the bottom substrate contains strip electrodes. Composite electrodes are further categorized into integral plate electrode (IPE) and rectilinear-patterned electrode (RPE). Meanwhile, the strip electrodes consist of auxiliary electrodes and pixel electrodes. During the focusing mode, the electric field can easily propagate through the LC layer. Simultaneously, the voltage on auxiliary electrodes is maintained lower than that on pixel electrodes to optimize the electric field distribution. To assess the operating efficiency of the ICE-LC, an evaluation of the conventional model is taken during the simulation. Simulation results show that the ICE-LC lens array achieves the shortest focal length at a low operating voltage. The pixel electrodes operate at 4.5 V rms , and the auxiliary electrodes at 0.9 V rms. This configuration provides an ideal refractive index profile in a relatively thick LC layer. Additionally, this configuration enables 2D/3D switchable display, outperforming current LC lens array in the equivalent aperture. [ABSTRACT FROM AUTHOR]

Cropland greatly impacts food security, energy supply, biodiversity, biogeochemical cycling, and climate change. Accurately and systematically understanding the effects of agricultural activities requires cropland spatial information with high resolution and a long time span. In this study, the first 1 km resolution global cropland proportion dataset for 10 000 BCE–2100 CE was produced. With the cropland map initialized in 2010 CE, we first harmonized the cropland demands extracted from the History Database of the Global Environment 3.2 (HYDE 3.2) and the Land-Use Harmonization 2 (LUH2) datasets and then spatially allocated the demands based on the combination of cropland suitability, kernel density, and other constraints. According to our maps, cropland originated from several independent centers and gradually spread to other regions, influenced by some important historical events. The spatial patterns of future cropland change differ in various scenarios due to the different socioeconomic pathways and mitigation levels. The global cropland area generally shows an increasing trend over the past years, from 0×106km2 in 10 000 BCE to 2.8×106km2 in 1500 CE, 6.2×106km2 in 1850 CE, and 16.4×106km2 in 2010 CE. It then follows diverse trajectories under future scenarios, with the growth rate ranging from 16.4 % to 82.4 % between 2010 CE and 2100 CE. There are large area disparities among different geographical regions. The mapping result coincides well with widely used datasets at present in both distribution pattern and total amount. With improved spatial resolution, our maps can better capture the cropland distribution details and spatial heterogeneity. The spatiotemporally continuous and conceptually consistent global cropland dataset serves as a more comprehensive alternative for long-term earth system simulations and other precise analyses. The flexible and efficient harmonization and downscaling framework can be applied to specific regions or extended to other land use and cover types through the adjustable parameters and open model structure. The 1 km global cropland maps are available at 10.5281/zenodo.5105689 (Cao et al., 2021a). [ABSTRACT FROM AUTHOR]

The construction of terraces is a key soil conservation practice on agricultural land in China providing multiple valuable ecosystem services. Accurate spatial information on terraces is needed for both management and research. In this study, the first 30 m resolution terracing map of the entire territory of China is produced by a supervised pixel-based classification using multisource and multi-temporal data based on the Google Earth Engine (GEE) platform. We extracted time-series spectral features and topographic features from Landsat 8 images and the Shuttle Radar Topography Mission digital elevation model (SRTM DEM) data, classifying cropland area (cultivated land of Globeland30) into terraced and non-terraced types through a random forest classifier. The overall accuracy and kappa coefficient were evaluated by 10 875 test samples and achieved values of 94 % and 0.72, respectively. For terrace class, the producer's accuracy (PA) was 79.945 %, and the user's accuracy (UA) was 71.149 %. The classification performed best in the Loess Plateau and southwestern China, where terraces are most numerous. Some northeastern, eastern-central, and southern areas had relatively high uncertainty. Typical errors in the mapping results are from the sloping cropland (non-terrace cropland with a slope of ≥ 5 ∘), low-slope terraces, and non-crop vegetation. Terraces are widely distributed in China, and the total terraced area was estimated to be 53.55 Mha (i.e., 26.43 % of China's cropland area) by pixel counting (PC) method and 58.46 ± 2.99 Mha (i.e., 28.85 % ± 1.48 % of China's cropland area) by error-matrix-based model-assisted estimation (EM) method. Elevation and slope were identified as the main features in the terrace/non-terrace classification, and multi-temporal spectral features (such as percentiles of NDVI, TIRS2, and BSI) were also essential. Terraces are more challenging to identify than other land use types because of the intra-class feature heterogeneity, interclass feature similarity, and fragmented patches, which should be the focus of future research. Our terrace mapping algorithm can be used to map large-scale terraces in other regions globally, and our terrace map will serve as a landmark for studies on multiple ecosystem service assessments including erosion control, carbon sequestration, and biodiversity conservation. The China terrace map is available to the public at 10.5281/zenodo.3895585 (Cao et al., 2020). [ABSTRACT FROM AUTHOR]

To solve the problem of measuring the combustion temperature of hydrogen gas, an improved two-colour pyrometer with suspended tungsten powder was developed and calibrated by a tungsten halogen lamp. The characteristic temperature parameters of the premixed 30% H 2 /70% air flame, including temperature distribution, proportion, maximum value, minimum value, and average value, could be measured and calculated using the improved two-colour pyrometer method and a python code. The temperature measuring results of H 2 -air mixture obtained by this technique were compared with that of thermocouples and previous studies. The results verified its feasibility to measure the flame temperature structure of H 2 combustion. Future work concerning the influential factors of the improved two-colour pyrometer was also mentioned. [Display omitted] • An improved two-colour pyrometer for measuring H 2 flame temperature was developed. • Tungsten powder was chosen as the auxiliary grey-body for the two-colour pyrometer. • Dynamic temperature mapping of H 2 combustion was performed with the technique. • Temperature characteristic parameters of H 2 -air flame were calculated and presented. [ABSTRACT FROM AUTHOR]

Owing to many fascinating properties including high thermal and chemical stability, excellent electrical insulation, fire-retardant and antibacterial properties, hexagonal boron nitride (hBN) has emerged as a prominent 2D material for broad applications. However, the production of high quality of hBN by chemical exfoliation from its precursor is still challenging. This paper presents a high-yield (+83%), low-cost and energy-efficient wet chemical exfoliation strategy, which produces few-layers (FL, 3–6 layers) of edge-functionalized (OH) hBN nanosheets with uniform size (486 ± 51 nm). This optimized preparation is established based on a comprehensive investigation on the key exfoliation parameters such as exfoliation temperature, time and amount of the oxidant (potassium permanganate). High quality of FL-hBN was confirmed by various characterization techniques including scanning electron microscopy coupled with energy dispersive X-ray, transmission electron microscopy, Raman, Fourier transform infrared spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy analyses. The outcome of this study paves a promising pathway to effectively produce hBN through a cost-efficient exfoliation approach, which has a significant impact on industrial applications. [ABSTRACT FROM AUTHOR]

Soybean is one of the most important crops in the world. There were dramatic changes in soybean plantation in China in recent decades. Heilongjiang Province has the greatest acreage of soybean plantation in China. Therefore, it is taken as a representative soybean region in this study for monitoring purposes. A 30-m dataset that mapped the areas of soybean planting in Heilongjiang Province was produced, for the period of 1984 ~ 2020, based on Landsat-5/7/8 images and the Google Earth Engine (GEE) platform. Maps were made with a random forest classifier and had overall accuracies better than 84%. The areas planted with soybean were calculated at both the provincial and city level and these were compared with the areas obtained from official statistics. At the provincial level, for more than 85% of the time periods, the areas given in the official statistics fell within the confidence intervals of the estimates. At the city level, soybean areas were also in good agreement with the statistical data in most years giving average R2 values as 0.75. These results demonstrate the effectiveness of using phenological features extracted by a double-logistic model and a linear harmonic model with the RF classifier to obtain a long time-series of soybean maps without using samples obtained by field measurements every year. [ABSTRACT FROM AUTHOR]

Cadmium tungstate crystals have attracted much attention because of its excellent scintillation performance. The existence of oxygen vacancies will reduce the luminous efficiency of the crystal, extend its luminous decay time and reduce light resolution of the crystal. However, the luminescence mechanism of the oxygen vacancies is not clear yet. Here, the optical properties of cadmium tungstate crystal with oxygen vacancies have been studied based on the Density Functional Theory (DFT). We calculated the defect formation energies of oxygen vacancies with three different charges (0, +1, +2), and corrected the band gap to make it more accurate. We obtained the absorption and emission peaks of the F center and F+ center for two different types of oxygen vacancies. The calculated absorption peaks of the F center of V OI and F+ center of V OII at 3.04 eV and 3.59 eV respectively, which are close to the experimental results (3.1 eV (400 nm) and 3.5 eV (350 nm)). So we speculate that these two obvious absorption peaks are caused by oxygen vacancies. [ABSTRACT FROM AUTHOR]

Preoperative anxiety is common and often comes with a higher probability of worse recovery. However, the neurological mechanism of the effect of preoperative anxiety on general anesthesia and subsequent awakening remains unknown. In this study, we report an anxious state results in delayed awakening in anxiety model mice from sevoflurane general anesthesia. More profound inhibition of DA neurons in the VTA contributes to delayed awakening. Optogenetic stimulation of VTA DA neurons can reverse the delay. The results indicate that VTA DA neurons may be involved in the delay in awakening from general anesthesia caused by anxiety. • Anxiety may lead delayed awakening from sevoflurane anesthesia. • VTA DA neurons regulate delayed awakening from sevoflurane anesthesia caused by anxiety state. • Optogenetic activation of VTA DA neurons can reverse the delay. [ABSTRACT FROM AUTHOR]

An aircraft ground power unit (GPU) can replace the auxiliary power unit (APU) in an aircraft while the aircraft is parked at an airport. Therefore, the problems associated with the oil consumption and air pollution of the APU are solved. However, the GPU is faced with challenges in terms of utilization, power quality, and fault tolerance. Thus, a novel centralized aircraft GPU based on a three-level neutral point clamped cascaded converter (3LNPC-CC) is introduced in this paper to improve utilization and power quality. Furthermore, an evaluation voltage balance strategy is proposed for the DC-port fault tolerance of the 3LNPC-CC. In addition, both the modulation of the phase shift pulse width modulation (PSPWM) and the control of the double closed loop are used in the 3LNPC-CC. A simulation platform including the control, modulation, and fault tolerance of the system is established to verify the feasibility and performance of the proposed GPU. In particular, it is used to evaluate the voltage balance strategy for DC-port faults. Moreover, a prototype of the GPU and relevant experiments are completed to verify the correctness and feasibility of the system and the strategy. [ABSTRACT FROM AUTHOR]