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Metal-organic frameworks (MOFs) hold immense promise for low-temperature denitrification (de-NOx) owing to their tunable pore size and active sites, nevertheless, their practical application is impeded by low yields. In this investigation, we introduce a synergistic modulated hydrothermal (SMHT) method designed to cooperatively control pre-cluster and solution pH using acetic acid and N, N-dimethylformamide, with the aim of enhancing MOFs yields. The TEOS&Mn-BTC-HY catalyst synthesized by the method of SMHT successfully increased the yield from 21 % of the input to 63 % compared with the TEOS&Mn-BTC catalyst synthesized by the hydrothermal method. Characterization analysis and performance testing reveal that the structure of TEOS&Mn-BTC-HY is minimally affected by the SMHT method, and its performance remains excellent. The de-NOxefficiency remained above 90 % in the temperature range of 90–300 ℃, and even under challenging conditions such as 6 % H2O or 100 ppm SO2at 150 ℃ for 10 h, the performance still exceeded 90 %. The designed SMHT process offers valuable insights for expanding MOFs production and further advancing the application of MOFs in the realm of de-NOx.

An organometallic iridium (Ir)-complex-functionalized nanographene catalyst Ir-PyPh-GCwas prepared via a two-step strategy involving amide ligand modification and metal Ir coordination. Ir-PyPh-GCshowed ultrahigh hydrogenation capability, good recyclability, and selectivity for carbonyl derivatives (ketones, aldehydes, and quinones) at a low temperature (40 °C). The as-prepared Ir-complex-based catalyst is less expensive, making it feasible for industrial application.

Microstructural evolution and dynamic recrystallization (DRX) mechanisms of a Ti−48Al−2Cr−2Nb (at.%) alloy prepared by selective electron beam melting (SEBM) during hot deformation at 1150 °C and 0.1 s−1were investigated by hot compression tests, optical microscope (OM), scanning electron microscope (SEM), electron back-scattered diffraction (EBSD) and transmission electron microscope (TEM). The results show that the initial microstructure of the as-SEBMed alloy exhibits layers of coarse γgrains and fine γ+α2+(α2/γ) lamellar mixture grains alternately along the building direction. During the early stage of hot deformation, deformation twins tend to form within the coarse grains, facilitating subsequent deformation, and a small number of DRX grains appear in the fine-grained regions. With the increase of strain, extensive DRX grains are formed through different DRX mechanisms in both coarse and fine-grained regions, involving discontinuous dynamic recrystallization mechanism (DDRX) in the fine-grained regions and a coexistence of DDRX and continuous dynamic recrystallization (CDRX) in the coarse- grained regions.

The distorted sensors in an array system will degrade the signal-to-interference-plus-noise ratio of received signal, resulting in performance deterioration. Without knowing the number of source signals, this article focuses on direction-of-arrival (DOA) estimation for a uniform linear array, in whicha small fraction of sensors are distorted. Meanwhile, source enumeration and detection of distorted sensors are realized. We model the array system with distorted sensors by introducing unknown gain and phase errors to the output signals, where the observations corresponding to the distorted sensors are treated as outliers. In this way, we tackle the DOA estimation task under the framework of low-rank and row-sparse matrix decomposition. We directly adopt the rank function and $\ell _{2,0}$-norm to obtain the low-rank and row-sparse matrices, respectively, instead of utilizing their surrogates as in the conventional methods. Therefore, the approximation bias is avoided. In detail, rank and $\ell _{2,0}$-norm optimization is converted to $\ell _{0}$-norm minimization. To solve it, we propose a shifted median absolute deviation-based strategy, achieving adaptive hard-thresholding control. The resultant optimization problem is then handled by proximal block coordinate descent, and the convergences of the objective function value and the solution sequence are proved. Extensive simulation results demonstrate the superior performance of the proposed algorithm in terms of DOA estimation, source number estimation, and distorted sensor detection.

We present FossilMorph, a user-friendly and open access software that offers rapid measurement and statistical analysis based on fossil images. Routine steps of image processing technologies and algorithms designed for three types of organic-walled microfossils (i.e., spheroidal type, filamentous type, and broken type) have been introduced in order to illuminate the rationale of FossilMorph. Two case studies on the form genera Leiosphaeridiaand Siphonophycusare used to test the utility of FossilMorph on the study of micropalaeontology, especially the Proterozoic spheroidal acritarchs. Future development of FossilMorph may be extended to deal with complex morphology and community-type preservation for wider applications.

To minimize parallax errors and achieve high spatial resolution positron emission tomography (PET) systems, developing depth-of-Interaction (DOI) encoding detectors has become a significant research topic. In this article, we investigated a dual-ended readout PET detector based on the multivoltage threshold (MVT) sampling method combined with a convolutional neural network (CNN) to calculate the pulse’s energy (MVT-CNN method). The MVT sampling method was used to acquire time-threshold samples and digitize scintillation pulses. The CNN model was employed to establish an accurate mapping between MVT sampling points and energy information. The dual-ended readout detector’s energy, DOI, and timing performance were evaluated with two irradiation configurations. The results demonstrated that the performance of the MVT-CNN method was close to that of the integration method based on oscilloscope sampling. Using the MVT-CNN method, the average energy resolution of the tested crystals over all depths was $14.5 \, \pm \, 1.2$ %, and the average DOI resolution was $2.81 \, \pm \, 0$ .70 mm. In the side irradiation configuration, the average coincidence timing resolution of the tested crystals at 2 mm depth was 435 ps. The performance of the dual-ended readout DOI-PET detector basedon the MVT-CNN method suggested that it could develop small animal and organ-dedicated PET systems with high sensitivity and uniform spatial resolutionxs.

Hematite (α-Fe2O3) constitutes one of the most promising photoanode materials for oxygen evolution reaction (OER). Recent research on Fe2O3have found a fast OER rate dependence on surface hole density, suggesting a multisite reaction pathway. However, the effect of heteroatom in Fe2O3on the multisite mechanism is still poorly understood. Herein we synthesized Fe2O3on Ti substrates (Fe2O3/Ti) to study the oxygen intermediates of OER by light-dark electrochemical scans. We identified the Fe-OH species disappeared and Ti-OH intermediates appeared on Fe2O3/Ti when pH = 11−14, which significantly improved the OER performance of Fe2O3/Ti. Combined with the density functional theory calculations, we propose that Ti atom acts as cocatalyst site and captures proton from neighboring Fe-OH species under highly alkaline condition, thereby promoting the coupling of Fe=O and reducing the energy barrier of the non-electrochemical step. Our work provides a new insight into the role of heteroatom in OER multisite mechanism based on clarifying the reaction intermediates.

In this work, a new treatment method combining ultrasonic vibration with FeCoNiCrCu high entropy alloy (HEA) coating was used to prepared Al/Mg bimetal through the lost foam compound casting. The effects of composite treatment involving ultrasonic vibration and HEA coating on interfacial microstructure and mechanical properties of Al/Mg bimetal were studied. Results demonstrate that the interface thickness of the Al/Mg bimetal with composite treatment significantly decreases to only 26.99% of the thickness observed in the untreated Al/Mg bimetal. The HEA coating hinders the diffusion between Al and Mg, resulting the significant reduction in Al/Mg intermetallic compounds in the interface. The Al/Mg bimetal interface with composite treatment is composed of Al3Mg2and Mg2Si/AlxFeCoNiCrCu+FeCoNiCrCu/δ-Mg+Al12Mg17eutectic structures. The interface resulting from the composite treatment has a lower hardness than that without treatment. The acoustic cavitation and acoustic streaming effects generated by ultrasonic vibration promote the diffusion of Al elements within the HEA coating, resulting in a significant improvement in the metallurgical bonding quality on the Mg side. The fracture position shifts from the Mg side of the Al/Mg bimetal only with HEA coating to the Al side with composite treatment. The shear strength of the Al/Mg bimetal increases from 32.16 MPa without treatment to 63.44 MPa with ultrasonic vibration and HEA coating, increasing by 97.26%.

It is known that salt ions are abundant in the natural environment where natural gas hydrates are located; thus, it is essential to investigate the self-preservation effect of salt ions on methane hydrates. The dissociation behaviors of gas hydrates formed from various NaCl concentration solutions in a quartz sand system at 268.15 K were investigated to reveal the microscopic mechanism of the self-preservation effect under different salt concentrations. Results showed that as the salt concentration rises, the initial rate of hydrate decomposition quickens. Methane hydrate hardly shows self-preservation ability in the 3.35% (mass) NaCl and seawater systems at 268.15 K. Combined the morphology of hydrate observed by the confocal microscope with results obtained from in situRaman spectroscopy, it was found that during the initial decomposition stage of gas hydrate below the ice point, gas hydrate firstly converts into liquid water and gas molecules, then turns from water to solid ice rather than directly transforming into solid ice and gas molecules. The presence of salt ions interferes with the ability of liquid water to condense into solid ice. The results of this study provide an important guide for the mechanism and application of the self-preservation effect on the storage and transport of gas and the exploitation of natural gas hydrates.

Thermal runaway (TR) of LiFePO4lithium-ion batteries (LFPs) can produce significant amounts of smoke, posing serious explosion hazards. This paper systematically investigated TR gas generation, explosion limits, explosion overpressure, and post-explosion gas compositions of 314 Ah LFPs under overcharging and overheating. Quantum chemical and explosion reaction kinetics calculations clarified the elementary reactions and compositional alterations occurring in gases and free radicals during the explosion process. The findings revealed that H2constituted the primary component of TR gases, comprising 47.64 % and 53.12 % of the overcharging and overheating, respectively, followed by CO2and CO. The ranges of explosion concentration for TR gases, when subjected to overheating and overcharging conditions, were 6.32–29.3 % and 6.83–26.91 %, respectively. At the point of maximum explosion overpressure (Pmax), the gas concentrations peaked at 15.86 % and 16.25 %. The elementary reaction R1 held a pivotal position in enhancing the explosion overpressure. As the TR gas concentration escalated, the Rate of Production (ROP) of R31 and R35 also surged, ultimately resulting in elevated concentrations of CO. The reactions R123, R250, and R279 facilitated the generation of H2while simultaneously consuming hydrocarbon gases. This resulted in a risk of secondary explosion of the TR gas after the explosion. Post-explosion gas residual quantities followed the order: C2H6< C2H4< CH4< H2< CO. The results revealed crucial insights for developing explosion prevention and suppression in the process safety industry and Energy Storage Systems.

•Characterize rockburst from rock material and external environmental factors.•Balance the category of rockburst datasets based on SMOTE.•Develop stacking models for rockburst prediction at four deep gold mines in China.•Verify the feasibility of the proposed stacking models by engineering cases.

To evaluate changes in dynamic cerebral autoregulation (CA) during short‐term and long‐term exposure to high altitude with ultrasonography, and also study the sex differences in the response of CA to altitude. We assessed the differences in dynamic CA and measured with Doppler ultrasound of the bilateral internal carotid artery (ICA), vertebral artery (VA), and middle cerebral artery (MCA) and the values of basic information within 48 hours and at 2 years after arrival at Tibet in 65 healthy Han young Chinese volunteers, meanwhile, we compared the resistance index (RI) and pulsatility index (PI) of the right MCA at inhale oxygen 8 minutes when a newcomer with 2 years after arrival at Tibet. With 2 years of altitude exposure, the SaO2of all subjects was above 90%, the mean PEF, DAP, and HR values decreased, HGB increased compared within 48 hours in same‐gender groups. Comparisons of cerebral hemodynamics between before 2 years and after 2 years within male and female groups, the mean RI and PI values of bilateral MCA after 2 years were significantly higher than before 2 years, at the same time, the mean RI and PI values of bilateral ICA were significant differences (P< .05) between male groups, with regard to female groups, showed that the mean RI and PI values of bilateral VA were significant differences (P< .05). Comparisons of Right MCA hemodynamics between after oxygen uptake 8 minutes and 2 years, the mean RI and PI values were no significant difference within male and female groups (P> .05). Acute mountain sickness could result from an alteration of dynamic autoregulation of cerebral blood flow, but the impaired autoregulation may be corrected with the extension of time, furthermore, the response of CA to altitude in males and females are different.

The titanium-tungsten alloy oxide (Ti-WO3) with controllable morphology and crystal phase is synthesized by the facile hot injection of titanium precursor. The alloyed Ti-WO3nanorods can stably maintain their cubic crystal phase during the redox reaction in an acidic environment, thus leading to dramatically enhanced response speed and cycling stability.

Silicon (Si) anodes offer significant potential due to their high capacity. However, their drastic volume change limits their utility, resulting in a shorter cycling life. In this paper, microsilicon particles and 6H-SiC particles were ball-milled and subsequently coated a layer of amorphous carbon, yielding Si/SiC@C composites. Computational and experimental results reveal that this heterostructure formed between Si and 6H-SiC enhances the electronic conductivity of the Si/SiC@C composites dramatically, as well as the Li ion diffusion rate. Thereby, the Si/6H-SiC heterostructure increases capacity and enhances the rate capability of the Si-based anode. Significantly, the conductivity of Si/SiC@C composites surpasses that of Si@C composites by a factor of around 330. Furthermore, tough, evenly distributed, and electrochemically inert 6H-SiC serves as a rigid framework. By reducing the expansion rate of Si-based anodes and mitigating mechanical stress during cycles, this improves the cycling stability. Additionally, the Si/SiC@C anodes demonstrate superior cycle performance (814.6 mAh g–1at 1 A g–1after 400 cycles with capacity retention of 88.0%) and excellent rate capability (762 mAh g–1at 5 A g–1).

This paper innovates a method for visualizing and quantifying color differences using relative hue and relative color concentration. Firstly, the relative hue and relative color concentration are proposed to solve the problem that conventional chromaticity parameters can't characterize color difference. Secondly, the color difference visualization and quantification method realized by weighting algorithm and VB programming can replace the conventional qualitative assessment by human eyes, which greatly improves the accuracy and repeatability. Finally, this paper takes the color difference problem of 2 a‐Si products as an example, and uses the method of this paper to test and analyze, and easily clarifies the cause of color difference as the uneven thickness of Panel SINx film layer and the slow settling rate of LED phosphor. Combined with principle analysis, optical simulation, and experimental verification, this paper finally proposes an improvement plan to solve the stubborn color difference problem of a‐Si products.

Although useful for distinguishing drug‐induced liver injury (DILI) from autoimmune hepatitis (AIH), liver biopsy is an invasive examination, and the presence of antinuclear antibody (ANA) positivity in patients with DILI could lead to excessive use of biopsy. Hence, we aimed to identify screening markers for histological features of AIH in patients with ANA‐positive DILI and verify their clinical outcomes after 1 year. This retrospective study included patients with ANA‐positive DILI, who underwent liver biopsy between January 2017 and April 2022. Two pathologists identified histological features of AIH. We detected the independent indicators associated with histological features of AIH using logistic regression. We evaluated their diagnostic ability for histological features of AIH using the receiver operating characteristic curve. The follow‐up period to determine clinical outcomes was 1 year after DILI onset. The χ2test or Fisher's exact test was used to compare categorical data and the Wilcoxon rank‐sum test was used to compare continuous variables. Two‐sided p< 0.05 was considered to indicate significance. The final analysis included 125 patients with ANA‐positive DILI, of whom 18 had AIH‐like histology. Factors independently associated with AIH‐like histology included globulin levels (odds ratio [OR] = 1.154, 95% confidence interval [CI] = 1.046–1.288; p= 0.006) and ANA titer ≥ 1:1000 (OR = 3.531, 95% CI = 1.136–11.303; p= 0.029). The optimal globulin cutoff indicating AIH‐like histology was 31.8 g/L. This globulin level in combination with ANA titer ≥ 1:1000 (area under the curve = 0.785, 95% CI = 0.738–0.832) provided a sensitivity of 100% and a specificity of 57% for indicating histological features of AIH in patients with ANA‐positive DILI. During follow‐up, more patients developed AIH in the group with AIH‐like histology than in the group without AIH‐like histology (35.3% vs. 0, p< 0.001). For patients with ANA‐positive DILI and ANA titer ≥ 1:1000 or globulin ≥ 31.8 g/L, liver biopsy is recommended to determine the presence of histological features of AIH and guide further monitoring. Serum markers for detecting histological features of autoimmune hepatitis (AIH) in patients with antinuclear antibody (ANA)‐positive drug‐induced liver injury (DILI) and their associations with the development of AIH are unclear. This retrospective cohort study identified serum globulin ≥ 31.8 g/L and ANA titer ≥ 1:1000 as potential screening markers. Patients with ANA‐positive DILI and histological features of AIH are more likely to develop AIH than those without these features. AIH, autoimmune hepatitis; ANA, antinuclear antibody; DILI, drug‐induced liver injury; HDS, herbal and dietary supplements; TCM, traditional Chinese medicines. Significant findings of the study Serum globulin ≥ 31.8 g/L and ANA titer ≥ 1:1000 could be screening markers for detecting histological features of autoimmune hepatitis (AIH) in patients with antinuclear antibody (ANA)‐positive drug‐induced liver injury. Patients with ANA‐positive DILI and histological features of AIH are more likely to develop autoimmune hepatitis than those without these features. What this study adds Some patients with ANA‐positive DILI present with histological features of AIH, which can be screened noninvasively by ANA titer ≥ 1:1000 and globulin ≥ 31.8 g/L before liver biopsy. Furthermore, patients who present with histological features of AIH should be followed up to monitor the development of AIH.

Programmed cell death protein 1 (PD-1) inhibitor sintilimab is effective in relapsed and refractory extranodal natural killer/T cell lymphoma (ENKTL), nasal type. We aimed to assess the safety and activity of sintilimab plus P-GEMOX (pegaspargase, gemcitabine, and oxaliplatin) in the first-line setting for advanced ENKTL.

The investigation was motivated by the widespread use of ultra-high-strength steels in cable-stayed bridges and armor steel plates. These structures are exposed to elevated risks from extreme loads, including vehicle impacts and blast loadings. The study aimed to investigate the mechanical properties of 1770 steel for applications in extreme conditions. The strain rates and temperatures ranged from 0.00095 s−1to 1303 s−1and 20 °C–900 °C, respectively. Tensile tests were conducted at various strain rates using a Split Hopkinson Tension Bar for dynamic testing and a universal testing machine for quasi-static testing at room temperature (20 °C). Quasi-static tension at elevated temperatures was carried out using an electromechanical testing machine coupled with a heating device. A uniform temperature distribution inside the specimens was ensured by a 30-min holding time. The results of the tensile test indicate that the 1770 steel displays notable thermal softening effects and strain rate hardening that differ from mild steel. The standard Johnson-Cook (J-C) model was found to be inadequate in accurately predicting the strain rate effects of this specimen. To address this issue, the strain rate parameter C in the standard model was adjusted to create the modified J-C model, which demonstrated good agreement with the experimental results. To further demonstrate the modified model and the identified parameters, drop hammer impact tests and corresponding numerical simulations were conducted. The impact test and numerical simulation results showed good agreement in terms of deformation and contact force. The mechanical properties and the constitutive models can serve as a design reference for the ultra-high-strength 1770 steel in extreme envirnments, as well as a theoretical basis for fitting material models of similar ultra-high-strength steels.

In this paper, the electrical performance of a‐Si TFT product on adjustable frequency display is studied. It is found that panel flicker behavior is related to a‐Si channel characteristics, which is related to the TFT Cgs capacitance increase at low display frequency. And it is also found that the relationship between brightness fluctuations and TFT leakage current affected by Poole‐Frenkel effect. By optimizing TFT process parameter to reduce the change of Cgs capacitance and reduce TFT leakage current in Poole‐Frenkel region, panel flicker performance is obviously improved. As a result, gaming display product can meet the G‐sync optical standard requirement.

The utilization of semiconductor-based photocatalytic technology holds immense promise for harnessing solar energy. However, the inherent issue of strong Coulombic attraction between photo-generated electrons and holes within a single photocatalyst often leads to rapid recombination, limiting efficiency. Addressing this challenge, the development of S-scheme heterojunction photocatalysts has emerged as an effective strategy. Nevertheless, the impact of this spatial separation on the photocatalytic reaction has remained largely unexplored. This study reveals that the recombination of useless charge carriers significantly influences the oxidation product. In the pristine ZnIn2S4system, the spatially unseparated holes interact with the H2O2generated on the surface of ZnIn2S4, all of which are converted to •OH with higher oxidation ability, causing excessive oxidation of 5-hydroxymethylfurfural (HMF). Conversely, the BiOBr/ZnIn2S4system, effective separation of electrons and holes in space, selectively oxidizes HMF into valuable 2,5-dimethylfuran (DFF) while efficiently generating H2O2(1.15 mmol∙L–1, 5 h). This outcome, elucidated through in-situ Fourier-transform infrared spectroscopy, density functional theory calculation, and femtosecond transient absorption spectroscopy, underscores the role of spatially separated charge carriers in influencing product selectivity within S-scheme heterojunctions. This work sheds new light on selective oxidation phenomena and underscores the significance of charge separation in S-scheme heterojunctions.

GPR101 is an orphan G protein-coupled receptor actively participating in energy homeostasis. Here we report the cryo-electron microscopy structure of GPR101 constitutively coupled to Gs heterotrimer, which reveals unique features of GPR101, including the interaction of extracellular loop 2 within the 7TM bundle, a hydrophobic chain packing-mediated activation mechanism and the structural basis of disease-related mutants. Importantly, a side pocket is identified in GPR101 that facilitates in silico screening to identify four small-molecule agonists, including AA-14. The structure of AA-14–GPR101–Gs provides direct evidence of the AA-14 binding at the side pocket. Functionally, AA-14 partially restores the functions of GH/IGF-1 axis and exhibits several rejuvenating effects in wild-type mice, which are abrogated in Gpr101-deficient mice. In summary, we provide a structural basis for the constitutive activity of GPR101. The structure-facilitated identification of GPR101 agonists and functional analysis suggest that targeting this orphan receptor has rejuvenating potential.

Biobased-functionalized metal–organic frameworks (Bio-FUN-MOFs) stand out from the crowd of candidates in the flame-retardant field due to their multipathway flame-retardant mechanisms and green synthesis processes. However, exploring and designing Bio-FUN-MOFs tend to counteract the problem of compromising the flame-retardant advantages of MOFs themselves, which inevitably results in a waste of resources. Herein, a strategy in which MOFs are ecologically regulated through acid–base balance is presented for controllable preparation of Bio-FUN-MOFs by two birds with one stone, i.e., higher flame-retardant element loading and retention of more MOF structures. Specifically, the buffer layer is created on the periphery of ZIF-67 by weak etching of biobased alkali arginine to resist the excessive etching of ZIF-67 by phytic acid when loading phosphorus source and to preserve the integrity of internal crystals as much as possible. As a proof of concept, ZIF-67 was almost completely etched out by phytic acid in the absence of arginine. The arginine and phytic acid-functionalized ZIF-67 with yolk@shell structure (ZIF@Arg–Co–PA) obtained by this strategy, as a biobased flame retardant, reduces fire hazards for polyurea composites. At only 5 wt % loading, ZIF@Arg–Co–PA imparted polyurea composites with a limiting oxygen index of 23.2%, and the peaks of heat release rate, total heat release, and total smoke production were reduced by 43.8, 32.3, and 34.3%, respectively, compared to neat polyurea. Additionally, the prepared polyurea composites have acceptable mechanical properties. This work will shed light on the advanced structural design of polymer composites with excellent fire safety, especially environmentally friendly and efficient biobased MOF flame retardants.

Natural gas hydrate is an energy resource for methane that has a carbon quantity twice more than all traditional fossil fuels combined. However, their practical application in the field has been limited due to the challenges of long-term preparation, high costs and associated risks. Experimental studies, on the other hand, offer a safe and cost-effective means of exploring the mechanisms of hydrate dissociation and optimizing exploitation conditions. Gas hydrate decomposition is a complicated process along with intrinsic kinetics, mass transfer and heat transfer, which are the influencing factors for hydrate decomposition rate. The identification of the rate-limiting factor for hydrate dissociation during depressurization varies with the scale of the reservoir, making it challenging to extrapolate findings from laboratory experiments to the actual exploitation. This review aims to summarize current knowledge of investigations on hydrate decomposition on the subject of the research scale (core scale, middle scale, large scale and field tests) and to analyze determining factors for decomposition rate, considering the various research scales and their associated influencing factors.

ABSTRACT Accurate prediction of local field distribution plays an important role in failure analysis of FRP laminates. Based on the variational asymptotic method (VAM), a asymptotic dimensional reduction model (ADRM) [...]

Accurate cropland information is critical for agricultural planning and production, especially in food-stressed countries like China. Although widely used medium-to-high-resolution satellite-based cropland maps have been developed from various remotely sensed data sources over the past few decades, considerable discrepancies exist among these products both in total area and in spatial distribution of croplands, impeding further applications of these datasets. The factors influencing their inconsistency are also unknown. In this study, we evaluated the consistency and accuracy of six cropland maps widely used in China in circa 2020, including three state-of-the-art 10-m products (i.e., Google Dynamic World, ESRI Land Cover, and ESA WorldCover) and three 30-m ones (i.e., GLC_FCS30, GlobeLand 30, and CLCD). We also investigated the effects of landscape fragmentation, climate, and agricultural management. Validation using a ground-truth sample revealed that the 10-m-resolution WorldCover provided the highest accuracy (92.3%). These maps collectively overestimated Chinese cropland area by up to 56%. Up to 37% of the land showed spatial inconsistency among the maps, concentrated mainly in mountainous regions and attributed to the varying accuracy of cropland maps, cropland fragmentation and management practices such as irrigation. Our work shed light on the promotion of future cropland mapping efforts, especially in highly inconsistent regions.

Inspired by sparse learning, the Markowitz mean-variance model with a sparse regularization term is popularly used in sparse portfolio optimization. However, in penalty-based portfolio optimization algorithms, the cardinality level of the resultant portfolio relies on the choice of the regularization parameter. This brief formulates the mean-variance model as a cardinality ( $\ell _{0}$ -norm) constrained nonconvex optimization problem, in which we can explicitly specify the number of assets in the portfolio. We then use the alternating direction method of multipliers (ADMMs) concept to develop an algorithm to solve the constrained nonconvex problem. Unlike some existing algorithms, the proposed algorithm can explicitly control the portfolio cardinality. In addition, the dynamic behavior of the proposed algorithm is derived. Numerical results on four real-world datasets demonstrate the superiority of our approach over several state-of-the-art algorithms.

Reported herein is direct C(sp3)–H arylation of unprotected benzyl anilines and alkylarenes via consecutive photoinduced electron transfer by visible light irradiation. Reductive quenching cycles and radical–radical cross-coupling were involved, and electron paramagnetic resonance experiments provide evidence for the formation of radical intermediates formed in situ. The protocol highlights transition metal free, external oxidant free, broad substrate scope, and high efficiency (>60 examples, up to 96%).

One-bit direction-of-arrival (DoA) estimation has drawn considerable attention in recent years with the increasing demand for low power consumption and high sampling rate. In this work, the 1-bit DoA estimation for deterministic signals is addressed from the viewpoint of sparse matrix recovery. First, using maximum likelihood (ML) and compressive sensing techniques, 1-bit DoA estimation is formulated as an ML-based row sparse matrix optimization in terms of least-absolute-shrinkage-and-selection-operator form with an $\ell _{2,1}$ regularization. After that, by complex-valued conjugate gradient and steepest descent operations, an iterative closed-form solution in the form of a row-sparse matrix is expected to be obtained. At last, the estimates of source numbers and DoAs are simultaneously completed by making sense of the structure of the row-sparse matrix. Numerical results showcase that the proposed algorithm outperforms the state-of-the-art approaches in terms of estimation accuracy.

Speckle noise is the main cause of quality degradation of optical coherence tomography (OCT) images. However, speckle noise reduction is challenging due to the complex cause for statistical modeling and the requirement of a large amount of annotated data for conventional supervised learning strategies. In this article, a novel semi-supervised learning method is proposed for speckle noise reduction in OCT images with limited labeled data. Our method creates pseudo-labels for co-teaching in the training process between a U-shaped convolutional neural network and a U-shaped Transformer with a shifted window to preserve both global information and local details. The proposed scheme encourages the consistency between different streams when the advantages of both are leveraged to compensate each other for better convergence. It shows robustness on both normal and pathological OCT images with different diseases and from different devices. Our method exhibits advantages over several other state-of-the-art methods of speckle noise reduction. To our knowledge, this work is the first attempt to combine convolutional networks and Transformers for semi-supervised speckle noise reduction and achieves promising results on different datasets.

To reduce production cost and inhibit the aggregation of graphene, graphene oxide and copper nitrate solution were used as raw materials in the paper. Cu particles were introduced to the graphene nanosheets by in-situ chemical reduction method in the hydrazine hydrate and sodium hydroxide solution, and the copper matrix composite reinforced with Cu-doped graphene nanosheets were fabricated by powder metallurgy. The synthesized Cu-doped graphene was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The relative density, hardness, electrical conductivity and tensile strength of the copper matrix composite reinforced with Cu-doped graphene were measured as well. The results show that copper ions and graphene oxide can be effectively reduced by hydrazine hydrate simultaneously. Most of oxygen functional groups on the Cu-doped graphene sheets can be removed dramatically, and Cu-doped graphene inhibit the graphene aggregation effectively. Within the experimental range, the copper matrix composites have good comprehensive properties with 0.5 wt% Cu-doped graphene. The tensile strength and hardness are 221 MPa and 81.6 HV, respectively, corresponding to an increase of 23% and 59% compared to that of pure Cu, and the electrical conductivity reaches up to 93.96% IACS. However, excessive addition of Cu-doped graphene is not beneficial for the improvement on the hardness and electrical conductivity of copper matrix composite.

Objective: To provide comprehensive data to understand mechanisms of vascular endothelial cell (VEC) response to hypoxia/re-oxygenation. Methods: Human umbilical vein endothelial cells (HUVECs) were employed to construct hypoxia/re-oxygenation-induced VEC transcriptome profiling. Cells incubated under 5% O2, 5% CO2, and 90% N2for 3 h followed by 95% air and 5% CO2for 1 h were used in the hypoxia/re-oxygenation group. Those incubated only under 95% air and 5% CO2were used in the normoxia control group. Results: By using a well-established microarray chip consisting of 58 339 probes, the study identified 372 differentially expressed genes. While part of the genes are known to be VEC hypoxia/re-oxygenation-related, serving as a good control, a large number of genes related to VEC hypoxia/re-oxygenation were identified for the first time. Through bioinformatic analysis of these genes, we identified that multiple pathways were involved in the reaction. Subsequently, we applied real-time polymerase chain reaction (PCR) and western blot techniques to validate the microarray data. It was found that the expression of apoptosis-related proteins, like pleckstrin homology-like domain family A member 1 (PHLDA1), was also consistently up-regulated in the hypoxia/re-oxygenation group. STRING analysis found that significantly differentially expressed genes SLC38A3, SLC5A5, Lnc-SLC36A4-1, and Lnc-PLEKHJ1-1may have physical or/and functional protein-protein interactions with PHLDA1. Conclusions: The data from this study have built a foundation to develop many hypotheses to further explore the hypoxia/re-oxygenation mechanisms, an area with great clinical significance for multiple diseases.

MiRNAs are critical regulators of target gene expression in many biological processes and are considered promising biomarkers for diseases. In this study, we developed a simple, specific, and sensitive miRNA detection method based on proximity ligation reaction, which is easy to operate. The method uses a pair of target-specific DNA probes immobilized on the same gold nanoparticles (AuNPs), which hybridize to the target miRNA. Hybridization brings the probes close together, allowing the formation of a continuous DNA sequence that can be amplified by Quantitative Real-time PCR (qPCR). This method eliminates the need for complex reverse transcription design and achieves high specificity for discriminating single base mismatches between miRNAs through a simple procedure. This method can sensitively measure three different miRNAs with a detection limit of 20 aM, providing high versatility and sensitivity, even distinguishing single-base variations among members of the miR-200 family with high selectivity. Due to its high selectivity and sensitivity, this method has important implications for the investigation of miRNA biological functions and related biomedical research.

The gut microbiota play a pivotal role in human health. Emerging evidence indicates that gut microbes participate in the progression of tumorigenesis through the generation of carcinogenic metabolites. However, the underlying molecular mechanism is largely unknown. In the present study we show that a tryptophan metabolite derived from Peptostreptococcus anaerobius, trans-3-indoleacrylic acid (IDA), facilitates colorectal carcinogenesis. Mechanistically, IDA acts as an endogenous ligand of an aryl hydrocarbon receptor (AHR) to transcriptionally upregulate the expression of ALDH1A3(aldehyde dehydrogenase 1 family member A3), which utilizes retinal as a substrate to generate NADH, essential for ferroptosis-suppressor protein 1(FSP1)-mediated synthesis of reduced coenzyme Q10. Loss of AHR or ALDH1A3largely abrogates IDA-promoted tumour development both in vitro and in vivo. It is interesting that P. anaerobiusis significantly enriched in patients with colorectal cancer (CRC). IDA treatment or implantation of P. anaerobiuspromotes CRC progression in both xenograft model and ApcMin/+mice. Together, our findings demonstrate that targeting the IDA–AHR–ALDH1A3axis should be promising for ferroptosis-related CRC treatment.

This article presents a compact dual-band filtenna with high selectivity and seven controllable radiation nulls for vehicle application. The proposed filtenna is composed of three dual-mode resonators and a feedline, which are etched on a 3D hollow substrate. To achieve dual-band responses with compact size, three dual-mode resonators are investigated, which feature broad band and controllable frequency ratio to fully cover WIFI bands. For miniaturization, filtering responses are realized by designing multi-path couplings between resonators and the feedline. Without increasing antenna size and extra filtering circuits, seven controllable radiation nulls are realized beside pass-bands. Therefore, the proposed filtenna possesses dual-band and broadband Quasi-elliptical filtering responses with compact size and high selectivity. Moreover, the in-band radiation performance is almost unchanged. To analyze and guide the antenna design, the working mechanisms are presented. For demonstration, the proposed dual-band filtering antenna is implemented with Laser Direct Structuring (LDS). The overall size of the proposed dual-band filtenna is 0.16*0.09*0.04${\bm{\lambda }}_0^3$ operating with the fractional bandwidth of 10.2% and 13.6%, respectively. The in-band radiation efficiency is of −1.5 dB and −1 dB, respectively. The proposed filtering antenna features compact size, controllable frequency ratio and radiation nulls and high in-band radiation, rendering it suitable for Shark-Fin scenarios.

Tensor completion (TC) refers to restoring the missing entries in a given tensor by making use of the low-rank structure. Most existing algorithms have excellent performance in Gaussian noise or impulsive noise scenarios. Generally speaking, the Frobenius-norm-based methods achieve excellent performance in additive Gaussian noise, while their recovery severely degrades in impulsive noise. Although the algorithms using the $\ell _{p}$ -norm ( $0&lt; p&lt; 2$ ) or its variants can attain high restoration accuracy in the presence of gross errors, they are inferior to the Frobenius-norm-based methods when the noise is Gaussian-distributed. Therefore, an approach that is able to perform well in both Gaussian noise and impulsive noise is desired. In this work, we use a capped Frobenius norm to restrain outliers, which corresponds to a form of the truncated least-squares loss function. The upper bound of our capped Frobenius norm is automatically updated using normalized median absolute deviation during iterations. Therefore, it achieves better performance than the $\ell _{p}$ -norm with outlier-contaminated observations and attains comparable accuracy to the Frobenius norm without tuning parameter in Gaussian noise. We then adopt the half-quadratic theory to convert the nonconvex problem into a tractable multivariable problem, that is, convex optimization with respect to (w.r.t.) each individual variable. To address the resultant task, we exploit the proximal block coordinate descent (PBCD) method and then establish the convergence of the suggested algorithm. Specifically, the objective function value is guaranteed to be convergent while the variable sequence has a subsequence converging to a critical point. Experimental results based on real-world images and videos exhibit the superiority of the devised approach over several state-of-the-art algorithms in terms of recovery performance. MATLAB code is available at https://github.com/Li-X-P/Code-of-Robust-Tensor-Completion.

In this letter, we put forth a novel strategy to boost the reliability of orthogonal frequency division multiplexing differential chaos shift keying (OFDM-DCSK) systems over doubly selective fading channels. Provided the accessibility of channel state information, singular value decomposition is exploited to partition the channel into distinct sub-channels, which is realized by multiplying the right singular vectors by the symbol matrix at the transmitter. Subsequently, the sub-channel associated with the largest singular value is allocated to the reference chaotic sequence, leading to a higher signal-to-noise ratio (SNR) of demodulated symbols and lower bit error rate (BER) at the receiver. Inspired by the water-filling principle, the BER can be further reduced by permuting the symbols in a strategic manner. This approach of channel decomposition integrated with symbol reallocation, referred to as singular-vector pre-coded OFDM-DCSK (SVP-OFDM-DCSK), is able to escalate the SNR over doubly selective channels, ultimately enhancing the system reliability. The BER of the SVP-OFDM-DCSK system is also analyzed. Simulation results demonstrate that the proposed system with and without symbol permutation step achieves lower BERs than existing schemes over doubly selective fading channels.

One-bit compressed sensing (1-bit CS) inherits the merits of traditional CS and further reduces the cost and burden on the hardware device via employing the 1-bit analog-to-digital converter. When the measurements do not involve sign flips caused by additive noise, most contemporary algorithms can attain excellent signal restoration. However, their recovery performance might significantly degrade if there is even a small portion of sign flips. In order to increase the estimation accuracy in noisy scenarios, we devise a new signal model for 1-bit CS to attain robustness against sign flips. Then, we give a double-sparsity optimization formulation of the restoration problem. Subsequently, we combine proximal alternating minimization and projected gradient descent to tackle the problem. Different from existing robust methodologies, our approach, referred to as robust one-bit CS (ROCS), does not require the number of sign flips. Furthermore, we analyze the convergence behavior of ROCS and show that the objective value and variable sequences converge. Numerical results using synthetic data demonstrate that ROCS is superior to the competing methods in terms of reconstruction error in noisy environments. ROCS is also applied to direction-of-arrival estimation and outperforms state-of-the-art approaches.

In the clades of animals that diverged from the bony fish, a group of Mas-related G-protein-coupled receptors (MRGPRs) evolved that have an active role in itch and allergic signals1,2. As an MRGPR, MRGPRX2 is known to sense basic secretagogues (agents that promote secretion) and is involved in itch signals and eliciting pseudoallergic reactions3–6. MRGPRX2 has been targeted by drug development efforts to prevent the side effects induced by certain drugs or to treat allergic diseases. Here we report a set of cryo-electron microscopy structures of the MRGPRX2–Gi1trimer in complex with polycationic compound 48/80 or with inflammatory peptides. The structures of the MRGPRX2–Gi1complex exhibited shallow, solvent-exposed ligand-binding pockets. We identified key common structural features of MRGPRX2 and describe a consensus motif for peptidic allergens. Beneath the ligand-binding pocket, the unusual kink formation at transmembrane domain 6 (TM6) and the replacement of the general toggle switch from Trp6.48to Gly6.48(superscript annotations as per Ballesteros–Weinstein nomenclature) suggest a distinct activation process. We characterized the interfaces of MRGPRX2 and the Gitrimer, and mapped the residues associated with key single-nucleotide polymorphisms on both the ligand and G-protein interfaces of MRGPRX2. Collectively, our results provide a structural basis for the sensing of cationic allergens by MRGPRX2, potentially facilitating the rational design of therapies to prevent unwanted pseudoallergic reactions.

Background:Although substantial efforts have been made by researchers to develop drugs, a disappointing reality is that the emergence of drug resistance is an unavoidable reality for the majority of patients. In recent years, emerging evidence suggests a connection between drug resistance and immune dysregulation. Summary:As a ubiquitously distributed, versatile innate immune cell, macrophages play essential roles in maintaining tissue homeostasis in a steady state. Nevertheless, it is becoming aware that macrophages undermine the action of therapeutic drugs across various disease types. Reprogramming macrophage function has been proven to be effective in restoring patient responsiveness to treatment. Herein, we comprehensively reviewed how macrophages respond to drugs and the mechanisms by which they contribute to treatment unresponsiveness in cancer, inflammatory diseases, and metabolic diseases. In addition, future prospects in macrophage-based combination therapy were discussed. Key Messages:Targeting macrophages is a promising strategy for overcoming drug resistance in immune disorders.

Sparse index tracking, as one of the passive investment strategies, is to track a benchmark financial index via constructing a portfolio with a few assets in a market index. It can be considered as parameter learning in an adaptive system, in which we periodically update the selected assets and their investment percentages based on the sliding window approach. However, many existing algorithms for sparse index tracking cannot explicitly and directly control the number of assets or the tracking error. This article formulates sparse index tracking as two constrained optimization problems and then proposes two algorithms, namely, nonnegative orthogonal matching pursuit with projected gradient descent (NNOMP-PGD) and alternating direction method of multipliers for $\ell _{0}$ -norm (ADMM- $\ell _{0}$ ). The NNOMP-PGD aims at minimizing the tracking error subject to the number of selected assets less than or equal to a predefined number. With the NNOMP-PGD, investors can directly and explicitly control the number of selected assets. The ADMM- $\ell _{0}$ aims at minimizing the number of selected assets subject to the tracking error that is upper bounded by a preset threshold. It can directly and explicitly control the tracking error. The convergence of the two proposed algorithms is also presented. With our algorithms, investors can explicitly and directly control the number of selected assets or the tracking error of the resultant portfolio. In addition, numerical experiments demonstrate that the proposed algorithms outperform the existing approaches.

Direction-of-arrival (DOA) estimation is a frequent need in the field of array signal processing. While many conventional algorithms achieve excellent performance in Gaussian noise, they are vulnerable to impulsive noise. Although several approaches have been proposed for robust DOA estimation against gross errors, their disadvantages might limit the applicability in practice. For instance, the maximum likelihood (ML) estimation-based algorithms involve high computational complexity, and $\ell _{p}$-multiple signal classification with $p\in (1,2)$ requires tweaking $p$ for handling different noises. In this work, we devise a capped Frobenius norm (CFN) for complex-valued data inspired by the truncated least squares loss function. Since the cap threshold is the boundary to differentiate the normal and outlier-contaminated entries, we propose a normalized median absolute deviation-based strategy for its automatic determination. In doing so, the accurate estimation is achieved in both Gaussian and impulsive noise. As the CFN is nonconvex and nonsmooth, we exploit the half-quadratic theory to simplify the resultant problem into a tractable optimization, which is then handled by alternating convex optimization with computationally efficient closed-form solution. Furthermore, its convergence behaviors are analyzed, i.e., the objective function value is convergent, and there exists a subsequence in the variable sequence converging to a critical point. Simulation results exhibit its superior performance over several state-of-the-art algorithms in terms of estimation accuracy and resolution capability. MATLAB code is available at https://github.com/Li-X-P/Code-Robust-DOA-Estimator.

The article discusses three successful digital technology start-up companies in China, namely coffee company Saturnbird Coffee, sugar-free beverage company Yuan Qi Sen Lin (YQSL), and cosmetics company Perfect Diary. It particularly focuses upon the firms' product innovations in relation to consumer desires, use of social media, and the integration of the Chinese economy into the worldwide supply chain and global value chain.

Using the advanced algorithm combining parallel computing, adaptive mesh re-griding and multigrid methods, quantitative 3D phase-field simulations of non-isothermal solidification of binary alloy were carried out. The 3D phase-field simulation results were compared with the analytical LKT (Lipton, Kurz and Trivedi) theory. For comparison, the simulation and analytical results for 2D cases were also given. The 3D phase-field simulation results support the transport portion of the LKT theory. However, the tip radius and tip velocity predicted by the simulations are not in good agreement with the LKT theory over the whole range of undercooling. The stability parameter calculated from phase-field simulations varies significantly with the Peclet number, indicating that the stability criterion, which assumes that the stability parameter is constant, is invalid.

Sex determination in plants gives rise to unisexual flowers. A better understanding of the regulatory mechanism underlying the production of unisexual flowers will help to clarify the process of sex determination in plants and allow researchers and farmers to harness heterosis. Androecious cucumber (Cucumis sativusL.) plants can be used as the male parent when planted alongside a gynoecious line to produce heterozygous seeds, thus reducing the cost of seed production. The isolation and characterization of additional androecious genotypes in varied backgrounds will increase the pool of available germplasm for breeding. Here, we discovered an androecious mutant in a previously generated ethyl methanesulfonate (EMS)-mutagenized library of the cucumber inbred line ‘406’. Genetic analysis, whole-genome resequencing, and molecular marker-assisted verification demonstrated that a nonsynonymous mutation in the ethylene biosynthetic gene 1-AMINOCYCLOPROPANE-1-CARBOXYLATE SYNTHASE 11(ACS11) conferred androecy. The mutation caused an amino acid change from serine (Ser) to phenylalanine (Phe) at position 301 (S301F). In vitroenzyme activity assays revealed that this S301F mutation leads to a complete loss of enzymatic activity. This study provides a new germplasm for use in cucumber breeding as the androecious male parent, and it offers new insights into the catalytic mechanism of ACS enzymes.

Antimony sulfoselenide (Sb2(S,Se)3) is a promising light absorption material because of its high photoabsorption coefficient, appropriate band gap, superior stability, and abundant elemental storage. As an emerging solar material, hydrothermal deposition of Sb2(S,Se)3solar cells has enabled a 10% efficiency threshold, where cadmium sulfide (CdS) is applied as an electron transport layer (ETL). The high-efficiency Sb2(S,Se)3solar cells largely employ CdS as the ETL. In terms of efficiency improvement, there are two questions regarding the CdS substrate: (1) the high roughness of CdS grown on F-doped tin oxide glass which increases the roughness of the absorber layer and (2) the low conductivity of CdS films because of low purity of CdS film grown by chemical bath deposition. In this study, we demonstrate an effective potassium chloride (KCl) post-treatment to modify the CdS ETL for improving the Sb2(S,Se)3solar cell efficiency. We found that KCl plays dual roles that reduce roughness and enhanceconductivity of the CdS films, thus acquiring a maximum efficiency of 9.98%, which is 9.2% higher than the control device. This study provides a new method for the surface engineering of CdS layer to improve the morphological and electrical properties, which is significant for improving the performance of CdS-based thin-film solar cells.

In this article, we propose a robust matrix completion approach based on $\ell _{0}$-norm minimization for target localization in sub-Nyquist sampled multiple-input–multiple-output (MIMO) radar. Owing to the low-rank property of the noise-free MIMO radar transmit matrix, our approach is able to recover the missing data and resist impulsive noise from the receive matrix. We adopt proximal block coordinate descent and adaptive penalty parameter adjustment by complex Laplacian kernel and normalized median absolute deviation. We analyze the resultant algorithm convergence and computational complexity, and demonstrate through simulations that it outperforms existing methods in terms of pseudospectrum, mean square error, and target detection probability in non-Gaussian impulsive noise, even for the full sampling schemes. While in the presence of Gaussian noise, our approach performs comparably with other sub-Nyquist methods.

Matrix completion refers to recovering a matrix from a small subset of its entries. It is an important topic because numerous real-world data can be modeled as low-rank matrices. One popular approach for matrix completion is based on low-rank matrix factorization, but it requires knowing the matrix rank, which is difficult to accurately determine in many practical scenarios. We propose a novel algorithm based on rank-one approximation that a matrix can be decomposed as a sum of outer products. The key idea is to find the basis vectors of the underlying matrix according to the observed entries, and gradually increase the vector number until an appropriate rank estimate is reached. In contrast to the conventional rank-one schemes that employ unchanging rank-one basis matrices, our algorithm performs completion from the vector viewpoint and is able to generate continuously updated rank-one basis matrices. Besides, we theoretically show that the developed method has a linear convergence rate and a smaller recovery error than existing rank-one based algorithms. Experimental results using both synthetic data and real-world images demonstrate that our solution has the best recovery performance among the competing algorithms when the observations are contaminated by Gaussian noise.