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Sparse representation and inversion have been widely used in the acquisition and processing of geophysical data. In particular, the low-rank representation of seismic signals shows that they can be determined by a few elementary modes with predominantly large singular values. We review global and local low-rank representation for seismic reflectivity models and then apply it to least-squares migration (LSM) in acoustic and viscoacoustic media. In the global singular value decomposition (SVD), the elementary modes determined by singular vectors represent horizontal and vertical stratigraphic segments sorted from low to high wavenumbers, and the corresponding singular values reflect the contribution of these basic modes to form a broadband reflectivity model. In contrast, local SVD for grouped patch matrices can capture nonlocal similarity and thus accurately represent the reflectivity model with fewer ranks than the global SVD method. Taking advantage of this favorable sparsity, we introduce a local low-rank regularization into LSM to estimate subsurface reflectivity models. A two-step algorithm is developed to solve this low-rank constrained inverse problem: the first step is for least-squares data fitting and the second is for weighted nuclear-norm minimization. Numerical experiments for synthetic and field data demonstrate that the low-rank constraint outperforms conventional shaping and total-variation regularizations, and can produce high-quality reflectivity images for complicated structures and low signal-to-noise data. [ABSTRACT FROM AUTHOR]

The propagation of seismic waves in attenuating anisotropic media exhibits amplitude dissipation and phase dispersion. To describe its effects, the fractional Laplacian pure visco‐acoustic wave equations capable of producing stable and noise‐free wavefields have been derived. However, except for acoustic approximation, previous wave equations utilize the approximations with lower accuracy in simplifying the denominator of the approximate complex‐valued dispersion relation, resulting in reduced accuracy. To address this concern, we use a combination of complex stiffness coefficients to replace the denominator term of the approximate complex‐valued dispersion relation. This approximation effectively reduces the loss of accuracy caused by ignoring the influence of the velocity anisotropy parameter ε and the attenuation anisotropy parameter εQ in the denominator term, leading to a wave equation with high accuracy in media with large anisotropic parameters ε and δ. In addition, the new wave equation only contains two high‐order spatial partial derivatives and has high computational efficiency. Theoretical analysis and numerical examples demonstrate that the proposed pure visco‐acoustic tilted transversely isotropic wave equation outperforms the previous pure visco‐acoustic wave equation in terms of simulation accuracy. The newly developed wave equation is well suited for the application of Q‐compensated reverse time migration and full waveform inversion in attenuating anisotropic media. [ABSTRACT FROM AUTHOR]

Seismic waves propagating in anisotropic earth media suffer from waveform distortion, which leads to degraded resolution in seismic data imaging if this adverse effect is not corrected. Additionally, the wavefields simulated by the traditional coupled pseudo‐acoustic wave equations contain undesired shear wave artefacts and are unstable when Thomsen's anisotropy parameter ε is less than δ. To address these issues, many pure qP‐wave equations are proposed to describe wave propagation in anisotropic media. However, these equations are either low precision or high accuracy but computationally expensive. Considering the trade‐off between the computation efficiency and simulation accuracy, we derive a pure qP‐wave equation from the exact dispersion formula in tilted transverse isotropic media. The newly derived equation has only two higher order partial derivatives, which can better balance the accuracy and efficiency than the previous pure qP‐wave equations. The least‐squares reverse time migration method can balance amplitudes, suppress migration artefacts and improve imaging resolution. Then, based on the newly derived pure qP‐wave equation, we derive the Born modelling operator and adjoint migration operator and develop an anisotropic least‐squares reverse time migration method. To achieve the accelerated convergence, we introduce a generalized minimum residual algorithm to implement the anisotropic least‐squares reverse time migration method. Numerical simulation results show that the proposed pure qP‐wave equation outperforms the previous equations in balancing the trade‐off between accuracy and efficiency. In addition, synthetic examples demonstrate the effectiveness and robustness of our proposed anisotropic least‐squares reverse time migration method in correcting the deviations due to anisotropic effects. [ABSTRACT FROM AUTHOR]

Seismic waves propagating through attenuating media induce amplitude loss and phase dispersion. Neglecting the attenuation effects during seismic processing results in the imaging profiles with weakened energy, mispositioned interfaces and reduced resolution. To obtain high‐quality imaging results, Q‐compensated reverse time migration is developed. The kernel of the Q‐compensated reverse time migration algorithm is a viscoacoustic wave equation with decoupled amplitude loss and phase dispersion terms. However, the majority of current decoupled viscoacoustic wave equations are solved using the computationally expensive pseudo‐spectral method. To enhance computational efficiency, we initiate our approach from the dispersion relation of a single standard linear solid model. Subsequently, we derive a novel decoupled viscoacoustic wave equation by separating the amplitude loss and phase dispersion terms, previously coupled in the memory variable. The newly derived decoupled viscoacoustic wave equation can be efficiently solved using the finite‐difference method. Then, we reverse the sign of the amplitude loss term of the newly derived viscoacoustic wave equation to implement high‐efficient Q‐compensated reverse time migration based on the finite‐difference method. In addition, we design a regularization term to suppress the high‐frequency noise for stabilizing the wavefield extrapolation. Forward modelling tests validate the decoupled amplitude loss and phase dispersion characteristics of the newly derived viscoacoustic wave equation. Numerical examples in both two‐dimensional and three‐dimensional confirm the effectiveness of the Q‐compensated reverse time migration based on the finite‐difference algorithm in mitigating the attenuation effects in subsurface media and providing high‐quality imaging results. [ABSTRACT FROM AUTHOR]

A comprehensive and robust dataset of tropospheric aerosol properties is important for understanding the effects of aerosol–radiation feedback on the climate system and reducing the uncertainties of climate models. The "Third Pole" of Earth (Tibetan Plateau, TP) is highly challenging for obtaining long-term in situ aerosol data due to its harsh environmental conditions. Here, we provide the more reliable new vertical aerosol index (AI) parameter from the spaceborne-based lidar CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) on board CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) for daytime and nighttime to investigate the aerosol's climatology over the TP region during 2007–2020. The calculated vertical AI was derived from the aerosol extinction coefficient (EC), which was rigorously quality-checked and validated for passive satellite sensors (MODIS) and ground-based lidar measurements. Generally, our results demonstrated that there was agreement of the AI dataset with the CALIOP and ground-based lidar. In addition, the results showed that, after removing the low-reliability aerosol target signal, the optimized data can obtain the aerosol characteristics with higher reliability. The data also reveal the patterns and concentrations of high-altitude vertical structure characteristics of the tropospheric aerosol over the TP. They will also help to update and make up the observational aerosol data in the TP. We encourage climate modelling groups to consider new analyses of the AI vertical patterns, comparing the more accurate datasets, with the potential to increase our understanding of the aerosol–cloud interaction (ACI) and aerosol–radiation interaction (ARI) and their climate effects. Data described in this work are available at 10.11888/Atmos.tpdc.300614 (Huang, 2023). [ABSTRACT FROM AUTHOR]

The spaceborne Electric Field Detector (EFD) is one of the payloads of the China Seismo-Electromagnetic Satellite (CSES-01), which can measure electric field data at near-Earth orbit for investigating fundamental scientific topics such as the dynamics of the top-side ionosphere, lithosphere–atmosphere–ionosphere coupling, and electromagnetic field emissions possibly associated with earthquake occurrence. The Extremely Low-Frequency (ELF) waveform shows anomalous step variations, and this work proposes an automatic detection algorithm to identify steps and analyze their characteristics using a convolutional neural network. The experimental results show that the developed detection method is effective, and the identification performance reaches over 90% in terms of both accuracy and area under the curve index. We also analyze the rate of the occurrence of steps in the three components of the electric field. Finally, we discuss the stability of the statistical results on steps and their relevance to the probe's function. The research results provide a guideline for improving the quality of EFD data, and further applications in monitoring the low-Earth electromagnetic environment. [ABSTRACT FROM AUTHOR]

[Display omitted] The topography of the Tibetan Plateau (TP) has shaped the paleoclimatic evolution of the Asian monsoon. However, the influence of the TP on the global climate, beyond the domain of the Asian monsoon, remains unclear. Here we show that the Pacific and Atlantic Oceans act as efficient repeaters that boost the global climatic impact of the TP. The simulations demonstrate that oceanic repeaters enable TP heating to induce a wide-ranging climate response across the globe. A 1 °C TP warming can result in a 0.73 °C temperature increase over North America. Oceanic repeaters exert their influence by enhancing the air-sea interaction-mediated horizontal heat and moisture transport, as well as relevant atmospheric circulation pathways including westerlies, stationary waves, and zonal-vertical cells. Air-sea interactions were further tied to local feedbacks, mainly the decreased air-sea latent heat flux from the weakening air-sea humidity difference and the increased shortwave radiation from sinking motion-induced cloud reduction over the North Pacific and Atlantic Oceans. Our findings highlight the crucial influence of TP heating variation on the current climate under a quasi-fixed topography, in contrast to topography change previously studied in paleoclimate evolution. Therefore, TP heating should be considered in research on global climate change. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau (TP) impacts local and remote atmospheric circulations, wherein it mechanically and thermally affects air masses or airflows. Moreover, the TP provides a key channel for substance transport between the troposphere and the stratosphere. This study reviews recent advances in research regarding land–atmosphere coupling processes over the TP. The TP experiences climate warming and wetting. Climate warming has caused glacier retreat, permafrost degradation, and a general increase in vegetation density, while climate wetting has led to a significant increase in the number of major lakes, primarily through increased precipitation. Local and regional climates are affected by interactions between the land and the atmosphere. Namely, the TP drives surface pollutants to the upper troposphere in an Asian summer monsoon (ASM) anticyclone circulation, before spreading to the lower stratosphere. Further, the thermal forcing of the TP plays an essential role in the ASM. TP forcing can modulate hemispheric‐scale atmospheric circulations across all seasons. The TP interacts with remote oceans through a forced atmospheric response and is substantially affected by the evolution of the Earth's climate via promoting Atlantic meridional overturning circulation and eliminating Pacific meridional overturning circulation. The extensive influence of the TP is facilitated by its coupling with the ASM in the summer; whereas its winter influence on climate mainly occurs through Rossby waves. The observed increasing trends of temperature and precipitation over the TP are projected to continue throughout the 21st century. Plain Language Summary: The impact of the Tibetan Plateau on atmospheric circulation and the climate has been of great interest to the scientific community. Here, we review the literature on the mechanisms of its climate effects, to provide an overview of recent progress in the field and directives for future research. Key Points: We summarize recent advances in climate change research and observations of the land–atmosphere coupling processes over the Tibetan Plateau (TP)We highlight the impact of the TP on the global climate, including atmospheric species transport, circulation, and air‐sea interactionsWe conclude projected future climate changes over the TP and discuss future research directives for assessing the TP's global climate impact [ABSTRACT FROM AUTHOR]

Numerous studies have confirmed that electromagnetic disturbances before earthquakes can be observed by satellites. In this study, we use the C-value method that includes the acoustic whistle signature; pre-seismic ionospheric electromagnetic disturbance signals were acquired based on the CSES-01 satellite electric field data, and the maximum value of C in the earthquake preparation zones increased continuously from 2.0 three days before the earthquake and reached a maximum weight of 3.0 on the day of the earthquake, after the earthquake, it gradually decreased and recovered to about 2.0; its the C values fluctuated between −2 and 3, it is different from the C values range −2–12 of the previous seismic case study using the DEMETER satellite, which may be related to the orbital altitude and revisit period of the satellite. Then, the C values were normalized, and the time series analysis of the obtained θ values were done, and the results showed that: In the pregnant zone, the background variation of the disturbance amplitude θ is within 2σ, and the maximum disturbance amplitude of θ starts to increase gradually from the seventh period (one period of 5 days, i.e., 35–39 days before the earthquake), it reached 2σ by the fourth pre-seismic cycle (20–24 days before the earthquake), and then dropped sharply to about 1.5σ in the third pre-seismic cycle (15–19 days before the earthquake), after two cycles of increase, the θ over the epicenter reached a maximum of 2.1σ at the time of the earthquake (combining the time of the earthquake and the satellite flight characteristics, the epicenter period is defined as January 25–January 29, 2020, and this defines the study time period line), and the θ decreases to within 2 times the standard range after the earthquake; The negative value of the disturbance amplitude θ in the central region of the pregnant seismic zone during the earthquake shows the transient energy release process. Through comparison, the θ values obtained by normalization based on the C-value method takes into account the variation of the background field, and the result can better reflect the energy change of the ionospheric field before the earthquakes. [ABSTRACT FROM AUTHOR]

The theoretical development of Schumann Resonances has spanned more than a century as a form of global natural electromagnetic resonances. In recent years, with the development of electromagnetic detection technology and the improvement in digital processing capabilities, the connection between Schumann Resonances and natural phenomena, such as lightning, earthquakes, and Earth's climate, has been experimentally and theoretically demonstrated. This article is a review of the relevant literature on Schumann Resonance observation experiments, theoretical research over the years, and a prospect based on space-based observations. We start with the theoretical background and the main content on Schumann Resonances. Then, observations and the identification of Schumann Resonance signals based on ground and satellite data are introduced. The research and related applications of Schumann Resonances signals are summarized in terms of lightning, earthquakes, and atmosphere. Finally, the paper presents a brief study of Schumann Resonances based on the China Seismo-Electromagnetic Satellite (CSES) and preliminary ideas about how to improve the identification and application of space-based Schumann Resonances signals. [ABSTRACT FROM AUTHOR]

Due to high computational costs and memory requirements, it is necessary to use coarse grids for least‐squares reverse time migration when processing large‐scale field data. According to the dispersion relation, strong numerical dispersion will occur in least‐squares reverse time migration images when the migration velocity of the shallow strata is low, reducing the resolution of the migration results. To overcome this shortcoming, we propose new least‐squares reverse time migration implementation method with a modified flux‐corrected transport technique. This algorithm involves two main steps: obtain an appropriate calibration parameter for flux‐corrected transport through forward modelling and perform least‐squares reverse time migration using flux‐corrected transport. We remove the non‐linear processing from conventional flux‐corrected transport algorithm often used in computational fluid dynamics based on the assumption that the seismic wavefield is relatively continuous and smooth without strong ripples, which makes it possible to apply flux‐corrected transport to least‐squares reverse time migration without increasing too much computation complexity. To suppress the numerical dispersion more effectively, the diffusion fluxes along the diagonal direction are added to flux‐corrected transport. Numerical tests on synthetic data and field data illustrate that compared to the conventional least‐squares reverse time migration method, the proposed method produces images with fewer migration artefacts, more accurate amplitudes and faster convergence speed on the coarse grids. [ABSTRACT FROM AUTHOR]

High-precision finite difference (FD) wavefield simulation is one of the key steps for the successful implementation of full-waveform inversion and reverse time migration. Most explicit FD schemes for solving seismic wave equations are not compact, which leads to difficulty and low efficiency in boundary condition treatment. Firstly, we review a family of tridiagonal compact FD (CFD) schemes of various orders and derive the corresponding optimization schemes by minimizing the error between the true and numerical wavenumber. Then, the optimized CFD (OCFD) schemes and a second-order central FD scheme are used to approximate the spatial and temporal derivatives of the 2D acoustic wave equation, respectively. The accuracy curves display that the CFD schemes are superior to the central FD schemes of the same order, and the OCFD schemes outperform the CFD schemes in certain wavenumber ranges. The dispersion analysis and a homogeneous model test indicate that increasing the upper limit of the integral function helps to reduce the spatial error but is not conducive to ensuring temporal accuracy. Furthermore, we examine the accuracy of the OCFD schemes in the wavefield modeling of complex structures using a Marmousi model. The results demonstrate that the OCFD4 schemes are capable of providing a more accurate wavefield than the CFD4 scheme when the upper limit of the integral function is 0.5π and 0.75π. [ABSTRACT FROM AUTHOR]

Previous research has documented the influence of eating together on people's food expectations and choices. We conducted an fMRI study to investigate the influence of the label "eating together" on behavioral and brain responses to healthy or unhealthy foods. The participants (N = 28, 13 females; mean age = 21.19) viewed food photos presented with a label of "eating together" or "eating alone" and estimated the palatability, pleasantness, and desirability of each food. The label "eating together" elicited more positive ratings for both healthy and unhealthy foods than the label "eating alone," and this effect of social context was larger for unhealthy than healthy foods. The label "eating together" also elicited greater activation in the left insula and the right posterior insula for unhealthy foods (p = 0.001 and p = 0.004, whole-brain corrected, respectively). These findings suggest that a label of "eating together" can enhance the reward values of foods, with a potentially greater enhancement for unhealthy foods. [ABSTRACT FROM AUTHOR]

The terrestrial ecosystem is an important source of atmospheric oxygen, and its changes are closely related to variations in atmospheric oxygen level. However, few studies have focused on the characteristics and driving forces behind terrestrial ecosystem oxygen sources. In this study, based on observations and net carbon flux simulations from the Sixth Coupled Model Intercomparison Project, we investigated temporal and spatial variations in terrestrial oxygen sources. As the largest source of atmospheric oxygen, the terrestrial ecosystem can produce approximately 7.10±0.38 gigatons of oxygen per year, and the tropics are the main oxygen producing regions. Notably, there are many "non-oxygen-producing lands", where the lands no longer provide oxygen to the atmosphere, located in the high latitudes and around the deserts of Central Asia. Long-term analysis reveals that anthropogenic activities and climate change are responsible for the variations in terrestrial oxygen sources owing to land-use changes and competing effects between net photosynthesis and heterotrophic respiration. By 2100, more oxygen will be produced from the low-middle latitudes, while the high latitudes will serve as a larger oxygen sink due to extreme land-use type changes and drastic increases in soil respiration. Through this study, we supplement the understanding of the modern oxygen cycle and help provide better estimates for future variations in atmospheric oxygen level. [ABSTRACT FROM AUTHOR]

One of the most important and continuously growing research areas in marine ecology is assessing the sustainability of ecosystems. The concept is traditionally approached by quantifying different anthropogenic pressures, such as top-down effects, overexploitation, invasive species, overfishing, and pollution. However, this perspective has been criticized for its inability to capture the complex interactions between natural factors (such as climate change), human factors, and sociopolitical factors that shape ecosystems. In this paper, we present a new structural model for assessing the sustainability of marine ecosystems, PCA-DEA-based model, as an extension to current models that incorporates these key interfaces into dynamic system modeling by including trade-offs on horizontal scales (e.g., decision making). [ABSTRACT FROM AUTHOR]

As oil and gas exploration moves toward complicated geological environments, high-resolution and true-amplitude seismic imaging becomes increasingly important for detecting and evaluating hydrocarbon reservoirs. Traditional ray-based and wave-equation imaging methods can be considered as the adjoint operator of seismic forward modeling, which are difficult to produce high-quality images in complicated structures because of limited frequency band, unbalanced illumination, and irregular acquisition. Least-squares migration (LSM) generates an inverse solution for subsurface reflectivity model with high image resolution and balanced amplitudes. Previous studies on LSM mainly focused on the developments of theoretical and practical strategies, but few on error and uncertainty analysis. We present a quantitative analysis method to evaluate the errors of LSM results. The $\phi _{\mathrm{ data}}$ and $\psi _{\mathrm{ data}}$ functions are first computed based on the local similarity and $L_{2}$ -norm misfit between observed and synthetic data. They are used as data-domain kinematic and dynamic errors, respectively. Then, these local functions are mapped to the subsurface using a Kirchhoff-integral relation to calculate image-domain errors. Numerical examples for synthetic and field data demonstrate that as the iteration of LSM increases, the total kinematic and dynamic errors are reduced, and they vary in different locations. For low signal-to-noise-ratio (SNR) field data, LSM might enlarge image errors at large iterations because of the overfitting issue, and proper regularization is very important to facilitate the convergence of LSM to a good solution. [ABSTRACT FROM AUTHOR]

The measurement of atmospheric O2 concentrations and related oxygen budget have been used to estimate terrestrial and oceanic carbon uptake. However, a discrepancy remains in assessments of O2 exchange between ocean and atmosphere (i.e. air-sea O2 flux), which is one of the major contributors to uncertainties in the O2-based estimations of the carbon uptake. Here, we explore the variability of air-sea O2 flux with the use of outputs from Coupled Model Intercomparison Project phase 6 (CMIP6). The simulated air-sea O2 flux exhibits an obvious warming-induced upward trend (∼1.49 Tmol yr−2) since the mid-1980s, accompanied by a strong decadal variability dominated by oceanic climate modes. We subsequently revise the O2-based carbon uptakes in response to this changing air-sea O2 flux. Our results show that, for the 1990–2000 period, the averaged net ocean and land sinks are 2.10±0.43 and 1.14±0.52 GtC yr−1 respectively, overall consistent with estimates derived by the Global Carbon Project (GCP). An enhanced carbon uptake is found in both land and ocean after year 2000, reflecting the modification of carbon cycle under human activities. Results derived from CMIP5 simulations also investigated in the study allow for comparisons from which we can see the vital importance of oxygen dataset on carbon uptake estimations. [ABSTRACT FROM AUTHOR]

By fitting observed data with predicted seismograms, least‐squares migration (LSM) computes a generalized inverse for a subsurface reflectivity model, which can improve image resolution and reduce artifacts caused by incomplete acquisition. However, the large computational cost of LSM required for simulations and migrations limits its wide applications for large‐scale imaging problems. Using point‐spread function (PSF) deconvolution, we present an efficient and stable high‐resolution imaging method. The PSFs are first computed on a coarse grid using local ray‐based Gaussian beam Born modeling and migration. Then, we interpolate the PSFs onto a fine‐image grid and apply a high‐dimensional Gaussian function to attenuate artifacts far away from the PSF centers. With 2D/3D partition of unity, we decompose the traditional adjoint migration results into local images with the same window size as the PSFs. Then, these local images are deconvolved by the PSFs in the wavenumber domain to reduce the effects of the band‐limited source function and compensate for irregular subsurface illumination. The final assembled image is obtained by applying the inverse of the partitions for the deconvolved local images. Numerical examples for both synthetic and field data demonstrate that the proposed PSF deconvolution can significantly improve image resolution and amplitudes for deep structures, while not being sensitive to velocity errors as the data‐domain LSM. Plain Language Summary: Seismic imaging is an important tool to detect hydrocarbon resource and study deep Earth's structure. Traditional ray‐based and wave equation imaging methods commonly extrapolate observed data and apply appropriate imaging condition to construct subsurface impedance interfaces. Mathematically, these methods can be considered as adjoint operators of seismic modeling, but they have difficulty to produce high‐quality images of complicated subsurface structures. To mitigate this issue, we present an efficient and stable high‐resolution imaging approach, i.e., the point‐spread function (PSF) deconvolution. The locally temporal and spatial limitations are utilized to efficiently compute the PSFs on a coarse grid using a ray‐based Gaussian beam propagator. Then, an on‐the‐fly interpolation on a fine grid and a wavenumber‐domain deconvolution are applied to improve image resolution. Numerical experiments for benchmark model and field data demonstrate the feasibility and adaptability of the proposed method for imaging complicated salt structure and low‐signal‐to‐noise data. Key Points: Conventional least‐squares migration is too expensive to be widely applied for large‐scale problems under current computational capacityAn efficient approach for calculating point‐spread functions using local modeling and migration is proposedThe point‐spread function deconvolution is then applied to incorporate the Hessian effect and improve image quality [ABSTRACT FROM AUTHOR]

Taklamakan Desert (TD) has been characterized by numerous heatwaves and dust storms, leading to negative effects on societies and ecosystems at regional and global scales. However, the association between heatwaves and dust storms is poorly known. In this study, we describe the association between heatwaves and dust events and propose a mechanism for such compound events in the TD. The results show that, from 1993 to 2022, the frequency and intensity of heatwaves in the TD have increased at a rate of 0.21 days year−1 and 0.02°C year−1, respectively. More than 40% of heatwaves existed with dust events, which significantly lagged behind heatwaves. Mechanically, the higher the air temperature, the hotter and drier the soil, leading to more dust emissions in the TD. In high-occurrence heatwave years, a large-scale wave train of “cyclone-anticyclone-cyclone” in the northwest-southeast direction was found, with the anticyclone of which hovered over the TD region. The anomalous anticyclones favored the formation and maintenance of heatwaves, and subsequent anomalous cyclones in the wave train triggered strong dust events followed by heatwaves. With climate warming, the compound events of heatwave and dust storm are becoming bigger hazards threatening the socioeconomic and ecological security in the TD, the profound study of which is critical to understanding regional extreme responses. [ABSTRACT FROM AUTHOR]

The decadal surface air temperature (SAT) variation over East Asia (EA) is characterized by an opposite pattern, warming over the northern EA along with cooling over the southern EA, and vice versa, fluctuating on decadal time scale. We found that Pacific Decadal Oscillation (PDO) has been largely responsible for the opposite decadal SAT variation. Positive (negative) phase of the PDO is related to the northern warming (cooling) and southern cooling (warming) over EA, and the decadal variation of the opposite SAT pattern is highly correlated with the PDO decadal variability, implying a decadal modulation of SAT by PDO. We investigated the influence of PDO on the opposite decadal SAT pattern by employing a dynamical adjustment method based on constructed circulation analogues. The results showed that the PDO associated variability in the large-scale atmospheric circulation over Eurasia, characterized by a dipole structure with cyclonic circulation occupying the northern Eurasia but anticyclonic circulation over the southern Eurasia when in positive PDO phase, is responsible for the opposite decadal SAT pattern. Further analysis on the origin of the anomalous atmospheric circulation was performed by combining observations and climate model simulations. Based on observations and the multi-model simulations of Atmospheric Model Intercomparison Project (AMIP) from the Coupled Model Intercomparison Project Phase 6 (CMIP6), we found a contribution of intrinsic atmospheric dynamics, which was further suggested by the results using the Community Atmosphere Model simulations. • Decadal temperature variation over East Asia is characterized by dipole pattern. • Pacific Decadal Oscillation is responsible for the decadal temperature variation. • Pacific Decadal Oscillation modulates temperature via atmospheric circulation anomaly. [ABSTRACT FROM AUTHOR]

Aim. Printing parameters have been studied extensively to improve printing performance, while resins have been studied to a lesser extent. Therefore, we explore the impact of value in the Munsell color system on the mechanical properties and accuracy of printed products. Materials and Methods. Resins having different values were prepared by mixing transparent resin and color pastes. We used plate models for mechanical measurement, crown-and bridge models for accuracy measurement, and disc models for color measurement. Results. The Group E resin, which had the lowest value, had the minimum ultimate flexural strength (61.199 MPa) and a relatively low elastic modulus (19.015 MPa). Excluding the d index, no significant difference in accuracy was observed. In terms of the d index of trueness, the result of the Group E resin was significantly low. The relative errors of trueness were less than 0.0727 μm. The relative errors of precision were less than 0.0093 μm. Conclusion. The value of a resin affects the mechanical properties and accuracy of printed products. It is better to secure flexural strength by using a lower-value resin. High-value resins have relatively low accuracies. [ABSTRACT FROM AUTHOR]

The propagation of seismic waves in attenuating and anisotropic earth media is accompanied by amplitude attenuation and phase distortion. If these adverse effects are not addressed in seismic imaging, we may end up with inaccurate reflector positions, dimming amplitudes, and reduced spatial resolution in the imaging results. We use a pure pseudo-viscoacoustic TTI wave equation as a forward engine to implement Q-compensated TTI reverse time migration (RTM) because the wavefields simulated by the conventional coupled pseudo-viscoacoustic tilted transversely isotropic (TTI) wave equation contain shear wave artifacts and are unstable when the anisotropic parameters ε < δ. The high-frequency noise in the wavefield will be amplified exponentially during amplitude-compensated extrapolation, resulting in numerical instability when using Q-compensated TTI RTM. To eliminate the destabilizing effect of boosted high-frequency noise, we introduce a complex velocity that can be used to describe amplitude compensation over the limited frequency band. Then, based on this complex velocity, we derive a stable amplitude-compensated operator and apply it to the Q-compensated TTI RTM. The numerical simulation results show that, in comparison with the coupled pseudo-viscoacoustic TTI wave equation, the pure pseudo-viscoacoustic TTI wave equation is free from shear wave artifacts and is not restricted by anisotropic parameters. In addition, the pure pseudo-viscoacoustic TTI wave equation has high accuracy in describing velocity anisotropy and attenuation isotropy. Synthetic and field data examples demonstrate the effectiveness of our Q-compensated TTI RTM in compensating amplitude dissipation and correcting phase distortion. [ABSTRACT FROM AUTHOR]

Ray theory gives a high‐frequency asymptotic solution of the wave equation, which has been widely used in the seismic study because of its high computational efficiency and good physical insights for elementary waves. However, the fundamental high‐frequency assumption makes it difficult to accurately simulate the finite‐frequency effect of wave propagations. On the other hand, the Gaussian beam, as one of the advanced ray‐based methods, overcomes the amplitude singularity problem near the caustics by introducing a complex‐valued paraxial approximation. But Gaussian beams only use the velocity and up to second‐order velocity derivative of central rays and thus does not accurately simulate the response of heterogeneity away from the rays. To bridge the gap between the ray theory and wave‐equation methods, we present a two‐way beam wave method and apply it to seismic imaging. A fan of central rays are first shot to extract local ray‐centered model parameters in the global Cartesian coordinates. Then, a finite‐difference method is used to solve the acoustic wave equation in the ray‐centered coordinates to simulate wave propagations near the central rays. The beam wave method can accurately simulate the response of the velocity heterogeneities in the ray tubes and therefore produces more accurate wavefields. In addition, we discretize the ray‐centered wave equation onto a non‐orthogonal grid, which considerably reduces the computational cost. We apply the two‐way beam wave method in seismic imaging and develop a beam wave reverse‐time migration. It inherits the advantages of both ray‐based and wave equation migrations, and produces clear images for complicated structures with fewer artifacts than traditional imaging methods. Plain Language Summary: Seismic ray theory has evolved from classical asymptotic ray theory, through paraxial ray theory and Maslov's method, and then to the Gaussian beam method. Although the computational accuracy of the ray‐based methods for seismic modeling and imaging have been greatly improved, the fundamental high‐frequency approximation still prevents them from accurately describing finite‐frequency wave propagations in complex structures. We introduce the idea of reverse‐time migration into the beam method and develop a two‐way beam wave scheme for seismic modeling and imaging. Local velocities in the vicinity of central rays are first extracted and then the finite‐difference approach is used to solve the wave equation in the ray‐centered coordinate. Accurate wavefield simulation and beam‐to‐beam imaging condition enables us to achieve clear migrated images with fewer artifacts than traditional Gaussian beam migration and reverse‐time migration. Numerical examples for benchmark models and field data demonstrate the feasibility and adaptability of the proposed two‐way beam wave method. Key Points: It is difficult for ray theory to accurately simulate seismic wave phenomena in areas with strong velocity variationsA two‐way beam wave method is proposed to bridge the gap between ray‐based and wave equation approachesA beam wave reverse‐time migration approach is developed to improve the image quality for complicated subsurface environments [ABSTRACT FROM AUTHOR]

Downward longwave radiation (DLR) is an important component of the global radiation budget, significantly influencing surface energy dynamics. Accurate quantification of aerosol impacts on surface DLR is crucial for refining numerical weather predictions and comprehending surface energy balance. While the impact of aerosols on downward shortwave radiation has garnered substantial attention, investigation into the longwave radiation effect of aerosols remains relatively limited. In this study, the impact of aerosols on surface DLR is quantified by using continuous radiation data, conventional meteorological observations, and aerosol optical depth (AOD) retrieved from the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite. These datasets span the period from 2011 to 2018 and are obtained from six stations of the Lake Taihu Flux Observational Network situated in Eastern China. The sensitivity of DLR to AOD (dDLR/dAOD) is determined through multiple linear regressions using both observational data and the Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) reanalysis. Additionally, a radiative transfer model is employed to derive the dDLR/dAOD. A three-variable linear regression of the observational data shows that DLR increases by 4.66 ± 1.99 W m−2 per unit increase in AOD (mean ± 1 standard deviation) under clear-sky conditions. The radiative transfer model and the three-variable linear regression of MERRA-2 reanalysis yield similar sensitivity values of 4.69 ± 1.23 W m−2 AOD−1 and 4.10 ± 0.25 W m−2 AOD−1, respectively. However, these sensitivity values are considerably smaller than those reported in previous studies. Plausible factors contributing to the observed variance in sensitivity values are discussed. These results help to improve our understanding on the aerosol longwave radiation effect over the Lake Taihu region in Eastern China. • Sensitivity of surface DLR to AOD over the Lake Taihu region was quantified with diverse data and methods. • Consistent estimates of dDLR/dAOD (4.10–4.69 W m−2 AOD−1) were obtained using observation, MERRA-2 data, and SBDART model. • These sensitivity values were generally lower than those reported in previous studies (4.9 to 62 W m−2 AOD−1). [ABSTRACT FROM AUTHOR]

The mpox epidemic had spread worldwide and become an epidemic of international concern. Before the emergence of targeted vaccines and specific drugs, it is necessary to numerically simulate and predict the epidemic. In order to better understand and grasp its transmission situation, and take some countermeasures accordingly when necessary, we predicted and simulated mpox transmission, vaccination and control scenarios using model developed for COVID-19 predictions. The results show that the prediction model can also achieve good results in predicting the mpox epidemic based on modified SEIR model. The total number of people infected with mpox on Dec 31, 2022 reached 83878, while the prediction of the model was 96456 with a relative error of 15%. The United States, Brazil, Spain, France, the United Kingdom and Germany are six countries with serve mpox epidemic. The predictions of their epidemic are 30543, 11191, 7447, 5945, 5606 and 4291 cases respectively, with an average relative error of 20%. If 30% of the population is vaccinated using a vaccine that is 78% effective, the number of infected people will drop by 29%. This shows that the system can be practically applied to the prediction of mpox epidemic and provide corresponding decision-making reference. • We constructed a general epidemic model to simulate and predict mpox outbreaks, and achieve good results. • The SEIQRDP model is constructed by improving the traditional SEIR model, which is closer to the reality. • Introduce the idea of inversion parameters of climate models to obtain parameters that are closer to the real situation. • The idea of parameterization scheme of climate models is introduced to describe different situations in the model. [ABSTRACT FROM AUTHOR]

Compared with traditional adjoint-based migration, least-squares migration (LSM) can reduce finite-frequency effects, remove acquisition footprints and improve spatial resolution by solving a linear inverse problem for subsurface reflectivity. One important requirement for the success of LSM is having an accurate migration velocity model. Because of low signal-to-noise ratio (SNR), inaccurate traveltime picking, lack of low-frequency signals and limited acquisition aperture, it is still challenging to build an accurate velocity model using ray-based tomography or full waveform inversion. LSM with large velocity errors results in erroneous reflector locations, strong swing artifact and even non-convergence. To mitigate these issues, we develop a novel least-squares imaging framework in the subsurface half-opening angle domain. Instead of using high-wavenumber velocity perturbations as the reflectivity model as in traditional LSM, we parameterize the wave equation with an angle-dependent reflectivity, and derive the corresponding linearized forward modeling and adjoint migration operators. Because Gaussian Beam migration naturally incorporates propagation directions in wavefield extrapolation, we compute the Green's function using the Gaussian beam summation method. To improve the common-image gather (CIG) quality for low-fold and low-SNR data, a shaping regularization over the half-opening angles is introduced in the conjugate gradient scheme to iteratively update the angle-dependent reflectivity model. A flattening-enhanced summation is used to compute the stacked images by accounting for the depth moveout of CIGs caused by velocity errors, and produces constructive stacking results. Numerical experiments for benchmark models and a land survey demonstrate that the proposed method can improve LSM convergence and produce high-quality angle-dependent and stacked images even with inaccurate migration velocity models. [ABSTRACT FROM AUTHOR]

This research proposes and empirically tests whether adjustments to post-recall advertising spending strategy can be used as an effective tool to create a competitive advantage in resources, thus impacting a firm's future sales decline after a product recall event. This paper explores where the firm's advertising resources should be allocated: the focal brand (the recalled brand), a non-focal brand (another brand in the portfolio), or the institutional brand (the family brand) in order to determine the optimal advertising spending strategy. The findings show that firms should allocate advertising spending to promote the institutional brand in order to mitigate the impact of spillover effects of recalls on a firm's future sales performance. [ABSTRACT FROM AUTHOR]

We conducted a study to investigate how self‐construal priming can modulate the influence of receptacles on people's food perception. Self‐construal refers to how an individual views the self, with interdependent or independent self‐construal describing the self as a context‐embedded or context‐independent entity, respectively. After reading an essay containing either interdependent or independent pronouns, each of 112 Chinese participants viewed photos of Asian noodles served on plates of different sizes and colors and rated their feelings about and willingness to pay for these foods. Compared to independent self‐construal priming, priming with the interdependent self‐construal elicited a greater influence of plate size on the participants' willingness to pay for the noodles as well as the pleasantness ratings of the noodles served on red plates. Collectively, these findings suggest that the consumers' processing of and sensitivity to contextual information can be modulated by self‐construal priming when they are evaluating food products. Practical applications: Previous research demonstrated that people from varied cultural backgrounds are differently susceptible to the influence of contextual cues, such as the receptacles in which foods or drinks are served. The results of this study suggested that priming with the interdependent self‐construal could strengthen the influence of plate size on the participants' judgments and decisions about foods. These findings provide insights into how the nudging effects of contextual cues may vary as a function of the consumers' self‐construal. Moreover, the findings of this study suggest that consumers' susceptibility to immediate contextual cues may be temporarily modulated via presenting verbal materials, which has direct implications in the practice of sensory nudging in the process of selling or serving foods. For example, advertisements or menus may be skillfully designed to contain cues that can prime self‐construal in customers to subtly modulate the influence of contextual cues on their judgment and decisions about foods. [ABSTRACT FROM AUTHOR]

As an important contributor to the habitability of our planet, the oxygen cycle is interconnected with the emergence and evolution of complex life and is also the basis to establish Earth system science. Investigating the global oxygen cycle provides valuable information on the evolution of the Earth system, the habitability of our planet in the geologic past, and the future of human life. Numerous investigations have expanded our knowledge of the oxygen cycle in the fields of geology, geochemistry, geobiology, and atmospheric science. However, these studies were conducted separately, which has led to onesided understandings of this critical scientific issue and an incomplete synthesis of the interactions between the different spheres of the Earth system. This review presents a five-sphere coupled model of the Earth system and clarifies the core position of the oxygen cycle in Earth system science. Based on previous research, this review comprehensively summarizes the evolution of the oxygen cycle in geological time, with a special focus on the Great Oxidation Event (GOE) and the mass extinctions, as well as the possible connections between the oxygen content and biological evolution. The possible links between the oxygen cycle and biodiversity in geologic history have profound implications for exploring the habitability of Earth in history and guiding the future of humanity. Since the Anthropocene, anthropogenic activities have gradually steered the Earth system away from its established trajectory and had a powerful impact on the oxygen cycle. The human-induced disturbance of the global oxygen cycle, if not controlled, could greatly reduce the habitability of our planet. [ABSTRACT FROM AUTHOR]

The pseudo-differential operator with symbol | k |α has been widely used in seismic modelling and imaging when involving attenuation, anisotropy and one-way wave equation, which is usually calculated using the pseudo-spectral method. For large-scale problems, applying high-dimensional Fourier transforms to solve the wave equation that includes pseudo-differential operators is much more expensive than finite-difference approaches, and it is not suitable for parallel computing with domain decomposition. To mitigate this difficulty, we present a truncated space-domain convolution method to efficiently compute the pseudo-differential operator |$\sqrt{-\nabla ^2}$|⁠ , and then apply it to viscoacoustic reverse-time migration. Although |$\sqrt{-\nabla ^2}$| is theoretically non-local in the space domain, we take the limited frequency band of seismic data into account, and constrain the approximated convolution stencil to a finite length. The convolution coefficients are computed by solving a least-squares inverse problem in the wavenumber domain. In addition, we exploit the symmetry of the resulting convolution stencil and develop a fast spatial convolution algorithm. The applications of the proposed method in Q -compensated reverse-time migration demonstrate that it is a good alternative to the pseudo-spectral method for computing the pseudo-differential operator |$\sqrt{-\nabla ^2}$|⁠ , with almost the same accuracy but much higher efficiency. [ABSTRACT FROM AUTHOR]

A novel coronavirus (COVID‐19) has caused viral pneumonia worldwide, posing a major threat to international health. Our study reports that city lockdown is an effective way to reduce the number of new cases and the nitrogen dioxide (NO2) concentration can be used as an environmental lockdown indicator to evaluate the effectiveness of lockdown measures. The airborne NO2 concentration steeply decreased over the vast majority of COVID‐19‐hit areas since the lockdown. The total number of newly confirmed cases reached an inflection point about two weeks since the lockdown and could be reduced by about 50% within 30 days of the lockdown. The stricter lockdown will help newly confirmed cases to decline earlier and more rapidly, and at the same time, the reduction rate of NO2 concentration will increase. Our research results show that NO2 satellite observations can help decision makers effectively monitor and manage non‐pharmaceutical interventions in the epidemic. Plain Language Summary: Since governments adopted epidemic control measures, NO2 levels in most of the affected regions dropped significantly, and NO2 satellite data can be used as an environmental indicator of lockdown and can help explain the implementation of government non‐pharmaceutical interventions. Key Points: The global airborne NO2 concentration steeply decreased over the vast majority of COVID‐19‐hit areasThe total number of newly confirmed cases reached an inflection point about two weeks after the lockdownNO2 satellite measurement can be adopted as an environmental lockdown indicator [ABSTRACT FROM AUTHOR]

This research examines the effects of consumers' culture and celebrity's gender role on source credibility and attitude toward brand. Using culture difference theory (individualism and Confucianism) helps to explain why sex scandals can result in a greater negative impact on the response of Chinese customers than US customers. Finally, we provide a celebrity-select suggestion to mitigate the negative damage brought by the endorser's sex scandal. Specifically, we conducted experiments by using a 2 (sex scandal vs. tax evasion) x2 (Confucianism vs. individualism) x3 (celebrity gender: male vs. female vs. transgender) between-subjects design. [ABSTRACT FROM AUTHOR]

The global oxygen cycle is one of the most important cycles on Earth for all aerobic organisms, and it is a basic constraint sustaining aerobic life. As a major component of the cycle, oceans are now experiencing widespread declines in oxygen concentrations. Here, based on model simulations we found that ocean deoxygenation occurs as a result of oceanic oxygen outgassing, which is tightly related with the marine warming. Although the O2 flux from the ocean to atmosphere is quite small compared with that of oceanic oxygen production, this outgassing accounts for almost all of the decline in marine oxygen and even exceeds the amount of the loss. The model projections indicate accelerated oxygen escape from the ocean under climate change. The oceanic outgassing will increase from 1.6 to 4.3 Gt/yr over the 21st century due to solubility and circulation changes related with warming, which may eventually lead to a more hypoxic ocean in the future. Plain Language Summary: It is well‐known that O2 is fundamental for all aerobic life. However, the oxygen content of the ocean has been declining during the past few decades. This phenomenon, known as the "ocean deoxygenation," will have widespread consequences, which could eventually threaten the marine ecosystems. In this study, we systematically diagnosed the global oceanic oxygen budget on the basis of earth system models and found enhanced O2 escape from the ocean to atmosphere. The O2 outgassing is directly responsible for ongoing deoxygenation, and it will continue to increase in the future. A shift in the oceanic oxygen cycle characterized by increasing oxygen escape has been occurring as a consequence of human‐induced climate change, followed by intensified ocean deoxygenation and resulting in severe damage to marine biota. Key Points: Based on the CMIP5 models, this article systematically diagnosed the global oceanic oxygen budget and its response to climate changeThe ocean deoxygenation was the direct consequence of the escape of oxygen from the ocean, tightly associated with marine warmingDue to continued warming, oxygen outgassing from ocean may increase in the next few decades, leading to a more hypoxic ocean in the future [ABSTRACT FROM AUTHOR]

With the accumulation of people's wealth and the improvement of purchasing power, more and more people are buying cars as a means of travel. Walking and cycling of the past have now become a car trip. License plate recognition technology is especially important in intelligent transportation systems. It has been widely used in large shopping malls or supermarket parking lots, highway toll stations, speeding violation supervision and other fields. However, the accuracy and efficiency of license plate image recognition are insufficient. To solve the above problems, we propose a license plate character recognition method based on local HOG and layered LBP feature fusion from the perspectives of image pre-processing, license location, characters' segmentation and recognition. First, pre-processing the license image area by highlighting the license plate image; then, the license plate is positioned based on wavelet decomposition and brightness moment; next the tilted license plate image is corrected, the license plate frame is adjusted, and characterization is performed by using the improved projection method based on the fact that the projection of the character is a single peak or a double peak. Finally, the local HOG and hierarchical LBP feature fusion methods are used to identify the license characters. The results show that the license plate's character recognition rate of the proposed method reaches 99.71%, and the time taken is small. This not only improves the character recognition rate, but also saves recognition time. The results show that the method has important practical significance in license plates' recognition. [ABSTRACT FROM AUTHOR]

Full-waveform inversion (FWI) is one of the most promising inversion methods in geophysics due to its theoretical completeness and high resolution. However, the inversion ability of FWI strongly relies on the accuracy of the initial model and the quality of the low-frequency data. For FWI, it is important to accurately recover low and middle wavenumber components (the background model). In order to invert for the background model, we use a new strategy to compose the plane-wave using reference source points. With the new algorithm, more plane-waves can be composed for a single ray parameter to obtain the background model by plane-wave multi-scale full-waveform inversion (PMFWI) method. By controlling the ray parameter in this method, the low to middle wavenumber components can be recovered in sequence. Composing several plane-waves for a single ray parameter enables the illumination to be significantly improved, even for incomplete data. As only a small number of plane-waves are needed in this method, the computation burden greatly decreases. Analysis of numerical tests also verifies that the proposed inversion strategy is robust, to a certain extent, for high-frequency or noisy data. Application of this method on a modified portion of a SigsBee 2A model illustrates that, combined with conventional FWI, PMFWI has suitable model accuracy, even for coarse initial model data and high-frequency data. [ABSTRACT FROM AUTHOR]

The spread of COVID-19 is accelerating. At present, there is no specific antiviral drugs for COVID-19 outbreak. This is a multicenter retrospective cohort study of patients with laboratory-confirmed COVID-19 infection pneumonia from 3 hospitals in Hubei and Guangdong province, 141 adults (aged ≥18 years) without ventilation were included. Combined group patients were given Arbidol and IFN-α2b, monotherapy group patients inhaled IFN-α2b for 10–14 days. Of 141 COVID-19 patients, baseline clinical and laboratory characteristics were similar between combined group and monotherapy group, that 30% of the patients leucocytes counts were below the normal range and 36.4% of the patients experienced lymphocytopenia. The duration of viral RNA of respiratory tract in the monotherapy group was not longer than that in the combined therapy group. There was no significant differences between two groups. The absorption of pneumonia in the combined group was faster than that in the monotherapy group. We inferred that Arbidol/IFN - 2 b therapy can be used as an effective method to improve the COVID-19 pneumonia of mild patients, although it helpless with accelerating the virus clearance. These results should be verified in a larger prospective randomized environment. [ABSTRACT FROM AUTHOR]

• Women scored higher than men on the centrality of visual product aesthetics (CVPA). • We examined the association between the CVPA and gray matter volume (GMV). • Women's CVPA was positively correlated to GMV in the left mOFC and dorsal striatum. • Men's CVPA scores were negatively correlated with GMV in the left mOFC. • Our results revealed gender difference in the association between the CVPA and GMV. Visual aesthetics influence consumers' perception, acquisition, and usage of products, but the level of significance that a commercial product's visual aesthetics hold for each consumer varies from one person to another. Such individual difference is referred to as the centrality of visual product aesthetics (CVPA). Previous research has revealed that female adults scored higher than male adults in the self-reported CVPA scale. In order to identify the neuroanatomical correlates of this gender difference, we conducted a voxel-based morphometry (VBM) study to examine the association between the CVPA and gray matter volume (GMV) in a large sample of healthy adults from mainland China. The results revealed positive correlations between the female participants' CVPA scores and the GMV in two brain areas liked to reward processing, namely the left medial orbitofrontal cortex (mOFC) and the left dorsal striatum. By contrast, the results revealed a negative correlation between the male participants' CVPA scores and their GMV in the left mOFC. Collectively, these findings suggest that the level of significance that a commercial product's visual aesthetics hold for consumers may be associated with the rewards that they are able to receive from them. These findings also provide empirical evidence about the neuroanatomical correlates of self-reported values. [ABSTRACT FROM AUTHOR]

Anti-resorptive agents like bisphosphonates have been widely used for the treatment of postmenopausal osteoporosis. However, their long-term safety and efficacy are still controversial. This study is to examine the effect of Asiatic acid (AA) in osteoclastic differentiation, and further to investigate its effect on bone quality in animals. Effect of AA on osteoclastic differentiation was measured by Tartrate-resistant acid phosphatase stain, bone resorption pit assays, and quantitative real-time polymerase chain reaction. Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and transforming growth factor-β (TGF-β) signaling were measured by western blot before and after AA treatment. Ovariectomized (OVX) wild-type or Smad7 partially knock out mice were used to evaluate the effects of AA on bone quality by micro-computed tomography, mechanical test, and histomorphometry. Results revealed a dose-dependent inhibitory effect of AA on osteoclastic differentiation. After AA treatment, Smad7 was upregulated, while NF-κB and TGF-β signaling were inhibited during osteoclastic differentiation. Results from animal study revealed that AA prevented bone from further loss caused by OVX and increased the mechanical properties of femur in wild-type animals. AA also prevented bone loss in the Smad7-deficient animals. When combining with OVX in the Smad7-deficient mice, AA could only partially preserve their bone mass. Taken together, we found that AA effectively inhibited osteoclastic differentiation and attenuated osteoporosis, which effects may be through TGF-β and NF-κB pathways. This study reveals that AA may be a potential anti-resorptive agent for postmenopausal osteoporosis. [ABSTRACT FROM AUTHOR]

Although atmospheric greenhouse gas concentrations continuously increased, there was relatively little change in global-averaged surface temperatures from 1998 to 2013, which is known as atmospheric warming slowdown. For further understanding the mechanism involved, we explored the energy redistribution between the atmosphere and ocean in different latitudes and depths by using data analysis as well as simulations of a coupled atmosphere-ocean box model. The results revealed that, compared with observational changes of ocean heat content (OHC) associated with rapid warming, the OHC changes related to warming slowdown are relatively larger in multiple ocean basins, particularly in the deeper layer of the Atlantic. The coupled box model also showed that there is a larger increasing trend of OHC under the warming slowdown scenario than the rapid warming scenario. Particularly, during the warming slowdown period, the heat storage in the deeper ocean increases faster than the ocean heat uptake in the surface ocean. The simulations indicated that the warming patterns under the two scenarios are accompanied by distinct outgoing longwave radiation and atmospheric meridional heat transport, as well as other related processes, thus leading to different characteristics of ocean heat uptake. Due to the global energy balance, we suggest this slowdown has a tight relationship with the accelerated heat transport into the global ocean. [ABSTRACT FROM AUTHOR]

Climate and climate change have always been a research focus of atmospheric sciences. This paper summaries research efforts, achievements and international contributions of the Chinese scientific community on climate and climate change over the past 70 years. The review is based on papers published officially in national or international scientific journals, and is organized to cover six aspects: (1) general climate studies; (2) impact of the Qinghai-Tibetan Plateau; (3) impact of the East Asian monsoon; (4) influences of teleconnection oscillation and westerlies; (5) climate dynamics and development of climate models; and (6) climate change. It is, however, to be noted that the present review can not be considered as an exhaustive one, since there is a huge body of literature in the field. [ABSTRACT FROM AUTHOR]

This article reviews recent progress in semi-arid climate change research in China. Results indicate that the areas of semi-arid regions have increased rapidly during recent years in China, with an increase of 33% during 1994–2008 compared to 1948–62. Studies have found that the expansion rate of semi-arid areas over China is nearly 10 times higher than that of arid and sub-humid areas, and is mainly transformed from sub-humid/humid regions. Meanwhile, the greatest warming during the past 100 years has been observed over semi-arid regions in China, and mainly induced by radiatively forced processes. The intensity of the regional temperature response over semi-arid regions has been amplified by land-atmosphere interactions and human activities. The decadal climate variation in semi-arid regions is modulated by oceanic oscillations, which induce land-sea and north-south thermal contrasts and affect the intensities of westerlies, planetary waves and blocking frequencies. In addition, the drier climates in semi-arid regions across China are also associated with the weakened East Asian summer monsoon in recent years. Moreover, dust aerosols in semi-arid regions may have altered precipitation by affecting the local energy and hydrological cycles. Finally, semi-arid regions in China are projected to continuously expand in the 21st century, which will increase the risk of desertification in the near future. [ABSTRACT FROM AUTHOR]

The Weather Research and Forecasting (WRF) Model is used in large-eddy simulation (LES) mode to investigate a lake-breeze case occurring on 12 June 2012 over the Lake Taihu region of China. Observational data from 15 locations, wind profiler radar, and the Moderate Resolution Imaging Spectroradiometer (MODIS) are used to evaluate the WRF nested-LES performance in simulating lake breezes. Results indicate that the simulated temporal and spatial variations of the lake breeze by WRF nested LES are consistent with observations. The simulations with high-resolution grid spacing and the LES scheme have a high correlation coefficient and low mean bias when evaluated against 2-m temperature, 10-m wind, and horizontal and vertical lake-breeze circulations. The atmospheric boundary layer (ABL) remains stable over the lake throughout the lake-breeze event, and the stability becomes even stronger as the lake breeze reaches its mature stage. The improved ABL simulation with LES at a grid spacing of 150 m indicates that the non-LES planetary boundary layer parameterization scheme does not adequately represent subgrid-scale turbulent motions. Running WRF fully coupled to a lake model improves lake-surface temperature and consequently the lake-breeze simulations. Allowing for additional model spinup results in a positive impact on lake-surface temperature prediction but is a heavy computational burden. Refinement of a water-property parameter used in the Community Land Model, version 4.5, within WRF and constraining the lake-surface temperature with observational data would further improve lake-breeze representation. [ABSTRACT FROM AUTHOR]

Reactive Oxygen Species (ROS) are an important part of the normal cell growth cycle and play essential roles in many biological functions. Many techniques have been developed to detect and measure the amount of ROS present in cells. These techniques include spectrophotometry, high performance liquid chromatography (HPLC), capillary electrophoresis with laser-induced-fluorescence detector (CE-LIF) and capillary electrophoresis-on-a-chip with LIF. As ROS has a short half-life outside of the cell, various fluorescent probes, such as dihydrorhodamine 123 (DHR 123), that are membrane permeable have been used in the detection of intracellular ROS. In this paper, micellar electrokinetic capillary chromatography (MEKC) was coupled with LIF detector. Fluorescent probe, 3′-(p-aminophenyl)-fluorescein (APF), was used to detect specific ROS in Chinese Hamster Ovary (CHO) suspension cells as well as attached mouse bone marrow-derived dendritic cells (BMDCs). Separation buffer composition was optimized at a concentration of 25 mM tetraborate buffer with 50 mM sodium dodecyl sulfate at pH 9.3 and lysis of the cells was done successfully with a buffer of 70% ethanol and 0.1mM sodium dodecyl sulfate using a cell amount of 1 × 107. ROS in cells was successfully analyzed by MEKC-LIF method developed, with acceptable RSD for time at 1.54% and area at 2.81%. [ABSTRACT FROM AUTHOR]

Summary: While consumers are increasingly used to purchasing online, virtual reality (VR) is well acknowledged to enhance consumer experience via immersive and interaction systems. In our research, we recruited 160 participants (80 per experiment) to compare their consumer experiences of choosing Fast‐Moving Consumer Goods (FMCGs) in a virtual store (via VR) and on an online webpage. Specifically, each participant was asked to choose four FMCGs (foods in Experiment 1 and non‐foods in Experiment 2) for the next 4 weeks, and they filled out the Positive and Negative Affect Scale before and after completing choice tasks. Results of the anova showed that there was a significant decrease in negative affect scores following both food and non‐food choices (Mbefore = 1.3 vs. Mafter = 1.2). Positive affect ratings were significantly higher for food choices in VR than online (MVR = 2.5 vs. Monline = 2.1), with no significant difference for non‐food choices. This highlights the impact of VR on food choice and its potential to transform human–food interactions. The study reveals that VR can narrow the gap between consumers' expectations and actual perceptions by creating an immersive and interactive shopping experience, thus significantly influencing consumer behaviour. [ABSTRACT FROM AUTHOR]

It is found that there are some anomalous high-energy nuclear-shaped regions in the VLF frequency band of the space electric field. To detect and statistically analyze these nuclear-shaped anomaly areas, this paper proposes a nuclear-shaped anomaly area detection method based on the electric field power spectrum image data of the China Seismo Electromagnetic Satellite (CSES-01). First, the logarithm of VLF frequency band data was calculated and rotated counterclockwise to create power spectrum images and label them to form a sample image dataset; then, images were enhanced (which involved resizing, scaling, rotation, gaussian denoising, etc.) to solve the problems of the model overfitting and sample imbalance. Finally, the U-net network model based on the ResNet50 encoder was trained to obtain the optimal kernel anomaly detection model ResNet50_Unet. Comparative experiments with various semantic segmentation algorithms show that the ResNet50_Unet model has the best performance. Applying this model to detect the electric field power spectrum images from November 2021 to February 2022, a total of 101 nuclear-shaped anomaly areas were found, distributed between 45° and 70° of the north–south latitude. This model can quickly detect nuclear-shaped anomaly regions from massive data, providing reference significance for the detection of other types of ionospheric spatial disturbances. At the same time, it has important scientific significance and practical value for understanding the ionosphere and space communication. [ABSTRACT FROM AUTHOR]

How convective boundary‐layer (CBL) processes modify fluxes of sensible (SH) and latent (LH) heat and CO2 (Fc) in the atmospheric surface layer (ASL) remains a recalcitrant problem. Here, large eddy simulations for the CBL show that while SH in the ASL decreases linearly with height regardless of soil moisture conditions, LH and Fc decrease linearly with height over wet soils but increase with height over dry soils. This varying flux divergence/convergence is regulated by changes in asymmetric flux transport between top‐down and bottom‐up processes. Such flux divergence and convergence indicate that turbulent fluxes measured in the ASL underestimate and overestimate the "true" surface interfacial fluxes, respectively. While the non‐closure of the surface energy balance persists across all soil moisture states, it improves over drier soils due to overestimated LH. The non‐closure does not imply that Fc is always underestimated; Fc can be overestimated over dry soils despite the non‐closure issue. Plain Language Summary: Large swirling motions, called large turbulent eddies, efficiently transport water vapor, carbon dioxide, and heat up and down throughout the convective boundary layer (CBL). To what extent scalar fluxes in the atmospheric surface layer (ASL) are modulated by large turbulent eddies from the top of the CBL (i.e., top‐down eddies) remains a recalcitrant problem in many fields spanning atmospheric sciences, hydrology, ecology, and climate change. Here, high‐resolution computational simulations of the CBL show that scalar fluxes in the ASL linearly change with height across soil wetness conditions largely due to changes in the interactions of top‐down processes and bottom‐up surface exchange. Such linear height‐dependence of the fluxes indicates that reported fluxes from direct turbulent measurements in the ASL are not identical to their sought surface values. As a result, the non‐closure of the surface energy balance occurs across all soil moisture conditions but improves as soil becomes dry. CO2 measured fluxes are underestimated over wet soils and overestimated over dry soils, which has its implication when interpreting CO2 exchanges from global flux measuring networks utilizing turbulence theories. Height dependence of fluxes, which confirms that the constant flux layer assumption is not routinely satisfied, is a fundamental reason for the non‐closure. Key Points: Asymmetric flux transport by bottom‐up and top‐down processes leads to varying flux divergence/convergence (FDC) in the surface layerLatent heat and CO2 fluxes are underestimated when soil is wet and overestimated when dry, but sensible heat flux is always underestimatedNon‐closure of the surface energy balance is regulated by varying FDC and improves for dry soils due to overestimated latent heat flux [ABSTRACT FROM AUTHOR]

COVID-19 pandemic appeared summer surge in 2022 worldwide and this contradicts its seasonal fluctuations. Even as high temperature and intense ultraviolet radiation can inhibit viral activity, the number of new cases worldwide has increased to >78% in only 1 month since the summer of 2022 under unchanged virus mutation influence and control policies. Using the attribution analysis based on the theoretical infectious diseases model simulation, we found the mechanism of the severe COVID-19 outbreak in the summer of 2022 and identified the amplification effect of heat wave events on its magnitude. The results suggest that approximately 69.3% of COVID-19 cases this summer could have been avoided if there is no heat waves. The collision between the pandemic and the heatwave is not an accident. Climate change is leading to more frequent extreme climate events and an increasing number of infectious diseases, posing an urgent threat to human health and life. Therefore, public health authorities must quickly develop coordinated management plans to deal with the simultaneous occurrence of extreme climate events and infectious diseases. • The global distribution of the COVID-19 outbreak in summer 2022 is consistent with heat waves. • Approximately 69.3% of COVID-19 cases could have been avoided if there is no heat waves in the summer of 2022. • Extreme heat events will continue to intensify, and heat-related health threats are projected to increase further. [ABSTRACT FROM AUTHOR]

Abstract We conducted three experiments designed to investigate the influence of drink color shown in virtual reality (VR) on the taste ratings of drinks in the real world. In Experiment 1, participants tasted Chinese red or green tea samples after seeing the VR-based simulation of the actual tea color, but the results did not reveal any significant influence of virtual color on the ratings of the tea taste. In Experiment 2, the virtual tea color was what participants associated with the taste of each type of tea, which did influence their saltiness ratings of the sampled tea. In Experiment 3, participants were shown the virtual tea colors that other people associated with the tea taste, which did not influence their evaluation of the tea taste. Collectively, these results demonstrated that visual cues from the virtual world and gustatory cues from the real world may be integrated to influence the perception of actual drink when the colors were generated based on one's own crossmodal correspondences. Highlights • We tested the effects of virtual drink color on the perceived taste in 3 experiments. • The effect of VR-based simulation of the actual tea color on taste ratings was not significant. • Simulation of one person's taste-associated color affected his/her saltiness ratings. • Simulation of other people's associated color did not influence taste ratings. • Participants may integrate visual cues from the VR and actual gustatory cues. [ABSTRACT FROM AUTHOR]