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To address the issue of weak robustness caused by parameter mismatches in model predictive control (MPC), model-free predictive control is widely adopted in motor driving systems. This approach replaces the a priori model with a data-driven model, eliminating the influence of physical parameters. However, the rotating coordinate system has various impacts on model accuracy, especially the inaccurate position signals and asymmetric controller that can cause errors. This article proposes a model-free predictive control strategy using a sinusoidal generalized universal model to directly control sinusoidal signals and improve model accuracy in reflecting the motion characteristics of the plant considering the past data. The model is designed based on signal variations from the plant, with online estimation of the coefficients using the recursive least square (RLS) algorithm to ensure model accuracy. To implement the control in a continuous-control-set (CCS) controller, the predictive signal is designed considering time-shift and Lagrange algorithms, and the basic performances and stability are analyzed in terms of pole/zero locations and differential equations. The proposed strategy is applied to a permanent magnet synchronous motor (PMSM) driving system as a predictive current control (PCC) strategy, and the experimental results under different operating conditions are provided to demonstrate the effectiveness of the proposed method, as well as its advantages in terms of model accuracy, current quality, and enhanced robustness compared to conventional control strategies.

High-resolution visualization of the deep brain is still a challenging and very significant issue. Multiphoton microscopy (MPM) holds great promise for high-spatiotemporal deep-tissue imaging under NIR-III and NIR-IV excitation. However, thus far, their applications have been seriously restricted by the scarcity of efficient organic probes. Herein, we designed and synthesized two donor–acceptor–donor-type conjugated small molecules (TNTand TNS) for in vivomouse deep-brain imaging with three- and four-photon microscopy under 1700 and 2200 nm excitation. With a selenium (Se) substitution, we synthesized two conjugated small molecules to promote their emission into the deep near-infrared region with high quantum yields of 55% and 20% in THF solvent, respectively, and their water-dispersive nanoparticles have relatively large absorption cross-sections in the 1700 and 2200 nm windows, respectively, with good biosafety. With these superiorities, these organic NPs achieve high-resolution deep-brain imaging viathree-photon and four-photon microscopy with excitation at 1700 and 2200 nm windows, and 1620 μm deep in the brain vasculature can be visualized in vivo. This study demonstrates the efficiency of NIR-emissive conjugated small molecules for high-performance MPM imaging in the NIR-III and NIR-IV window and provides a route for the future design of organic MPM probes.

Soil tensile strength is a critical parameter governing the initiation and propagation of tensile cracking. This study proposes an eco-friendly approach to improve the tensile behavior and crack resistance of clayey soils. To validate the feasibility and efficacy of the proposed approach, direct tensile tests were employed to determine the tensile strength of the compacted soil with different W-OH treatment concentrations and water contents. Desiccation tests were also performed to evaluate the effectiveness of W-OH treatment in enhancing soil tensile cracking resistance. During this period, the effects of W-OH treatment concentration and water content on tensile properties, soil suction and microstructure were investigated. The tensile tests reveal that W-OH treatment has a significant impact on the tensile strength and failure mode of the soil, which not only effectively enhances the tensile strength and failure displacement, but also changes the brittle failure behavior into a more ductile quasi-brittle failure behavior. The suction measurements and mercury intrusion porosimetry (MIP) tests show that W-OH treatment can slightly reduce soil suction by affecting skeleton structure and increasing macropores. Combined with the microstructural analysis, it becomes evident that the significant improvement in soil tensile behavior through W-OH treatment is mainly attributed to the W-OH gel's ability to provide additional binding force for bridging and encapsulating the soil particles. Moreover, desiccation tests demonstrate that W-OH treatment can significantly reduce or even inhibit the formation of soil tensile cracking. With the increase of W-OH treatment concentration, the surface crack ratio and total crack length are significantly reduced. This study enhances a fundamental understanding of eco-polymer impacts on soil mechanical properties and provides valuable insight into their potential application for improving soil crack resistance.

Noble metals often exhibit excellent catalytic activity when downsized into two-dimensional (2D) metals owing to their high atomic utilization and unique electronic properties. However, the controllable formation of 2D metals/support composites with clean interfaces/surfaces for practical applications still remains a synthetic bottleneck, with rather limited cases of 2D metals prepared through metal–support bonds. Herein, we developed a built-in electronic interface-guided method for in situ reduction of preadsorbed Pt atoms into 2D Pt metals along the surface of 2D nitrogen-doped carbon (NC) support through the electronic interaction at nonbonded metal–support interface. The interfacial electron exchange, driven by the difference in work functions between 2D Pt metals and NC support, enables the controllable synthesis of 2D Pt-based Schottky heterojunctions with clean interfaces/surfaces and a mean Pt thickness of 1.3 nm. Both experimental and theoretical results confirm the enhanced electron exchange at the interface between 2D Pt and the 2D NC support, resulting in a doubled electron density for 2D Pt. Consequently, the electron-rich 2D Pt metals exhibit remarkable mass activity of 67.3 A mgPt–1for the hydrogen evolution reaction (HER) and a turnover frequency (TOF) value of 117 h–1in the electrocatalytic hydrogenation of phenol, notably outperforming those of the commercial Pt/C catalyst by a factor of 16.8 and 4.0, respectively. Our efficient built-in electronic interface-guided method not only facilitates the synthesis of novel 2D metal/2D support Schottky heterojunctions but also lays the groundwork for designing more powerful electronic interface catalysts with enhanced and diversified functionalities.

The 17th Paralympic Summer Games recently took place in Paris, France, and Chinese athletes performed exceptionally well. As of September 6, Team China was leading the medal tally, securing first position in both gold medals and total medals for the past five Paralympic Summer Games. The Chinese delegation consisted of 284 athletes, ranging in age from 15 to 48, participating in 302 events across 19 sports. China's success can be attributed to its emphasis on the protection of people with disabilities, athlete selection mechanism, rehabilitation and training measures, and the development of Paralympic sports projects. The country has also seen an increase in training facilities and venues for Paralympic sports. The promotion of disability sports is part of China's National Fitness Program and efforts to build a strong sports nation. Major international sporting events in China have contributed to creating a more inclusive environment for people with disabilities. [Extracted from the article]

Aim: Nonpharmaceutical interventions (NPIs) are important strategies to utilize in reducing the negative systemic impact pandemic disasters have on human health. However, early on in the pandemic, the lack of prior knowledge and the rapidly changing nature of pandemics make it challenging to construct effective epidemiological models that can be used for anti-contagion decision-making. Subject and methods: Based on the parallel control and management theory (PCM) and epidemiological models, we developed a Parallel Evolution and Control Framework for Epidemics (PECFE), which can optimize epidemiological models according to the dynamic information during the evolution of pandemics. Results: The cross-application between PCM and epidemiological models enabled us to successfully construct an anti-contagion decision-making model for the early stages of COVID-19 in Wuhan, China. Using the model, we estimated the effects of gathering bans, intra-city traffic blockades, emergency hospitals, and disinfection, forecasted pandemic trends under different NPIs strategies, and analyzed specific strategies to prevent pandemic rebounds. Conclusion: The successful simulation and forecasting of the pandemic showed that the PECFE could be effective in constructing decision models during pandemic outbreaks, which is crucial for emergency management where every second counts.

The mechanical behaviors of deep rocks have always posed a challenge for the implementation and safe operation of major underground engineering projects. To this end, this study modified the existing mainstream rock mechanics instruments equipped with a dynamic disturbance loading system and developed a second‐generation TFD‐2000/D triaxial instrument. The first‐generation device is equipped with an independent disturbance system and an advanced EDC‐580 all‐digital servo controller, which can apply disturbing load independently, implement the function of cyclic disturbance, and combine dynamic and static disturbances. The instrument was found to be reliable for use in analyzing the damage process of rocks in the disturbance test of marbles. The second‐generation instrument tackles three limitations of the first‐generation instrument: (i) it upgrades the strain measurement system and uses extensometers with linear variable differential transformers to accurately measure deformation; (ii) it uses the self‐balanced chamber to replace the Hoek–Franklin triaxial cell and auto‐balancing triaxial pressure chamber; and (iii) the loading rod is independently equipped with an EDC‐580 all‐digital servo controller, which measures precise loads. The experimental findings confirmed that the second‐generation instrument can be used for rock mechanics testing under cyclic disturbance loading, the disturbance–stress relaxation cycle, and the creep–fatigue cycle. In this sense, the second‐generation instrument can be a useful addition to deep rock mechanical instruments and provide a valuable reference. Two modifications were made to the TFD‐2000/D rock triaxial instrument to achieve the rock in fatigue creep alternation, variable amplitude cyclic disturbance, and constant fatigue loading on rocks. After the test, it could be well adapted for the study of strong disturbance and timing‐dependent properties of deep rocks. The development of the dynamic rock mechanics instrument is clarified, and the three major shortcomings of the existing instruments are summarized.Based on the conventional triaxial instrument, the first generation of the TFD‐2000/D triaxial instrument was developed, which can apply disturbing load independently, implementing the function of cyclic disturbance and combined dynamic and static disturbances.The second generation of the TFD‐2000/D triaxial instrument is improved to achieve variable amplitude cyclic loading, low‐frequency high‐level ground stress loading, and cyclic dynamic disturbance alternating with creep. The development of the dynamic rock mechanics instrument is clarified, and the three major shortcomings of the existing instruments are summarized. Based on the conventional triaxial instrument, the first generation of the TFD‐2000/D triaxial instrument was developed, which can apply disturbing load independently, implementing the function of cyclic disturbance and combined dynamic and static disturbances. The second generation of the TFD‐2000/D triaxial instrument is improved to achieve variable amplitude cyclic loading, low‐frequency high‐level ground stress loading, and cyclic dynamic disturbance alternating with creep.

Since the number of candidate vectors is increased in the multistep model predictive control (MMPC) strategy, its calculation burden becomes a serious problem in implementation. To make full use of the limited processor resources effectively and improve control performances, an MMPC with the adaptive prediction horizon (PH), control horizon (CH), and online selecting weighting factor is proposed in this article and applied to a permanent magnet synchronous motor (PMSM) driving system as the current controller. A hysteresis principle is designed to judge the current operating state to online adjust PH and CH in the MMPC within the normal timescale, and a real-time branch and bound algorithm is designed to online select a suitable weighting factor based on the overtimescale caused by the long CH. More effective availability of the processor resources by the proposed method is analyzed and its advantages including improved current impact, reduced switching frequency, and decreased influences of some parameter mismatches with suitable stator current quality are demonstrated by the simulation and experimental results compared with some conventional control strategies.

Due to the harsh operating environment and complex operating conditions of electric vehicles (EVs), the physical parameters of the motor undergo nonlinear changes, leading to mismatches in both the physical model and system inertia. To address this issue, an adaptive inertia observer-based model-free predictive current control (MF-PCC) strategy is proposed in this paper, and applied to the EV's permanent magnet synchronous motor (PMSM) driving system to adjust the system inertia online. The current load of the EV is converted to mass and load inertia. An adaptive inertia method is designed to achieve inertia matching between system inertia and load inertia based on online estimated load torque, reducing the influence of inertia mismatch. The implementation of the proposed method requires no physical parameters to eliminate their effects. The control performance is analyzed in principle using Bode diagrams and zero-pole maps with different sampling periods and inertia ratios. The effectiveness and correctness of the proposed method are demonstrated through experimental results compared with the MF-PCC with fixed inertia and conventional PCC strategies, as well as the advantages of better dynamics and current quality with enhanced robustness through adaptive inertia.

Hydroformylation is an industrial process for the production of aldehydes from alkenes1,2. Regioselective hydroformylation of propene to high-value n-butanal is particularly important, owing to a wide range of bulk applications of n-butanal in the manufacture of various necessities in human daily life3. Supported rhodium (Rh) hydroformylation catalysts, which often excel in catalyst recyclability, ease of separation and adaptability for continuous-flow processes, have been greatly exploited4. Nonetheless, they usually consist of rotationally flexible and sterically unconstrained Rh hydride dicarbonyl centres, only affording limited regioselectivity to n-butanal5–8. Here we show that proper encapsulation of Rh species comprising Rh(I)-gem-dicarbonyl centres within a MEL zeolite framework allows the breaking of the above model. The optimized catalyst exhibits more than 99% regioselectivity to n-butanal and more than 99% selectivity to aldehydes at a product formation turnover frequency (TOF) of 6,500 h−1, surpassing the performance of all heterogeneous and most homogeneous catalysts developed so far. Our comprehensive studies show that the zeolite framework can act as a scaffold to steer the reaction pathway of the intermediates confined in the space between the zeolite framework and Rh centres towards the exclusive formation of n-butanal.

Ultralocal is always used to solve the problem of weak robustness in predictive control to resist the influences caused by some time-varying physical parameters in the motor driving system. However, the achieved model cannot reflect the motion characteristics of the motor accurately and timely. Considering the influences on the model accuracy caused by nonlinear terms, a model-free predictive current control (MF-PCC) using extended affine ultralocal is proposed in this article for solving these issues. A data-driven model of extended affine ultralocal is built containing a two-order term based on affine arithmetic, and all coefficients in the model are online estimated by the recursive least square algorithm, including the input gain in the MF-PCC strategy based on the conventional ultralocal. The proposed method is completely independent from prior knowledge of the physical parameters of the controlled system. The proposed method is applied to a permanent magnet synchronous motor driving system, and the simulation and experimental results demonstrate the effectiveness and advantages including improved current quality and robustness compared with the MF-PCC strategy based on the conventional ultralocal model.

Recently, data analysis is used in model-free predictive control to mitigate the effects of parameter mismatches in parametric models. However, the finite-control-set (FCS) type cannot fully satisfy high-quality requirements due to the variable switching frequency, and it is necessary to consider the continuous-control-set (CCS) type to achieve better control performances. Nevertheless, the use of conventional time series structures in CCS model-free predictive control algorithms poses a challenge due to the complex design of control laws. To address this issue, this article proposes a CCS model-free predictive control based on a time-series subspace, which is then applied to a permanent magnet synchronous motor (PMSM) driving system. This method constructs a time-series subspace model from data and creates a suitable control law using the recursive least squares algorithm and Lagrange method without any time-varying physical parameters, to predict the future behavior of the stator voltage. The stability of the proposed method is analyzed through Bode diagrams and zero/pole maps under different conditions. A complete set of experiments proves the feasibility and advantages including improved current quality, tracking performances, and system noises compared to the conventional control strategies

Since a data-driven model is adopted to describe the operating state of the plant in the model-free predictive control, it has been widely used in the motor driving realm to eliminate the influences caused by parameter mismatches and enhance the robustness of the system. However, due to the fixed model structure and heavy calculating process, it is difficult to obtain an improved control performance using time-series models in continuous-control-set (CCS) predictive algorithms. To solve these problems, a model-free predictive current control (MF-PCC) using adaptive ultralocalized time-series is proposed in this article, and applied to a permanent magnet synchronous motor driving system as the current controller. The model structure is improved as a variable, and its orders are online adjusted according to the designed adaptive law and the current operating state of the system. The complex discrete-time transfer functions in the model are ultralocalized to simplify the realization in the CCS-type controller. All required coefficients in the model are estimated by the recursive least squares algorithm, and the optimal gain is also found by the particle swarm optimization algorithm. The effectiveness of the proposed method is demonstrated by the experimental results, as well as the advantages of the proposed method, including better model accuracy and current quality with suitable robustness compared with the conventional time-series based MF-PCC.

High myopia (HM) is the primary cause of blindness, with the microstructural organization and composition of collagenous fibers in the cornea and sclera playing a crucial role in the biomechanical behavior of these tissues. In a previously reported myopic linkage region, MYP5 (17q21–22), a potential candidate gene, LRRC46(c.C235T, p.Q79X), was identified in a large Han Chinese pedigree. LRRC46 is expressed in various eye tissues in humans and mice, including the retina, cornea, and sclera. In subsequent cell experiments, the mutation (c.C235T) decreased the expression of LRRC46 protein in human corneal epithelial cells (HCE-T). Further investigation revealed that Lrrc46−/−mice (KO) exhibited a classical myopia phenotype. The thickness of the cornea and sclera in KO mice became thinner and more pronounced with age, the activity of limbal stem cells decreased, and microstructural changes were observed in the fibroblasts of the sclera and cornea. We performed RNA-seq on scleral and corneal tissues of KO and normal control wild-type (WT) mice, which indicated a significant downregulation of the collagen synthesis-related pathway (extracellular matrix, ECM) in KO mice. Subsequent in vitrostudies further indicated that LRRC46, a member of the important LRR protein family, primarily affected the formation of collagens. This study suggested that LRRC46is a novel candidate gene for HM, influencing collagen protein VIII (Col8a1) formation in the eye and gradually altering the biomechanical structure of the cornea and sclera, thereby promoting the occurrence and development of HM.

It is generally thought that under basal conditions, neurons produce ATP mainly through mitochondrial oxidative phosphorylation (OXPHOS), and glycolytic activity only predominates when neurons are activated and need to meet higher energy demands. However, it remains unknown whether there are differences in glucose metabolism between neuronal somata and axon terminals. Here, we demonstrated that neuronal somata perform higher levels of aerobic glycolysis and lower levels of OXPHOS than terminals, both during basal and activated states. We found that the glycolytic enzyme pyruvate kinase 2 (PKM2) is localized predominantly in the somata rather than in the terminals. Deletion of Pkm2in mice results in a switch from aerobic glycolysis to OXPHOS in neuronal somata, leading to oxidative damage and progressive loss of dopaminergic neurons. Our findings update the conventional view that neurons uniformly use OXPHOS under basal conditions and highlight the important role of somatic aerobic glycolysis in maintaining antioxidant capacity.

High-resolution range profile (HRRP) is indispensable for modern radar automatic target recognition (RATR) systems and commonly has noisy background and misalignment along the range dimension. In this article, we propose a novel algorithm for HRPP recognition with the improvement of recognition accuracy, stability against range translation, and robustness to noise background. This method divides the HRRP into patches and encodes the patches to latent feature vectors via a multihead attention mechanism, modeling the spatial dependence, eliminating the influence of range translation, and focusing on the target area. A decoder is adopted to reconstruct the HRRP and improve the robustness against the noise. Experiments on measured data prove that the proposed algorithm outperforms other existing methods with recognition accuracy increased significantly, sensitivity to the range translation eliminated, and noise robustness improved. This study provides a promising and effective approach for HRRP target recognition.

Ruthenium oxide (RuO2), due to its comparable binding energy with *H and cost-effectiveness against Pt, has emerged as a pivotal electrocatalyst for oxygen evolution reaction (OER). In the present study, RuO2nanocrystals (NCs) and nanowires (NWs) were obtained by a molten salt process and the morphology, crystal structure, and local bonding features were examined by using electron microscopy and X-ray absorption spectroscopy. From the electrochemical measurement, both RuO2NCs and NWs exhibit favorable stability and activity toward oxygen evolution reaction in an alkali medium, althought NCs exhibit higher activity, which is likely attributed to the larger surface area and the high local structural disorder. The theoretical calculation reveals that RuO2NWs with a primary (110) orientation show a higher overpotential due to its d-band center’s proximity to the Fermi level versus (101). The present work suggests that the molten salt process could be an efficient method for producing metal oxide catalysts with tailorable geometry and performances.

The article "Treasures of the Phoenix Kingdoms" in Beijing Review highlights an exhibition at the National Museum of China in Beijing featuring over 200 Bronze Age artifacts from Hubei Province, central China. These artifacts, including bronzeware, jadeware, lacquerware, and silk fabrics, were produced by the people of the Zeng and Chu states during the early Zhou Dynasty. The exhibition showcases the cultural significance of the Phoenix Kingdoms, named after the mythical bird that played a prominent role in their culture. One of the most popular items on display is a bronze drum base from the tomb of Marquis Yi of Zeng, known for its intricate design featuring dragons. [Extracted from the article]

An exhibition at the Minsheng Art Museum in Beijing explores early Chinese civilization, showcasing the cultures of 13 major heritage sites in China. The exhibition includes artifacts from sites such as Yangshao, known for its painted pottery culture, Erlitou, one of the capital cities during the Xia Dynasty, and Yinxu, an ancient capital city of the Shang Dynasty. The exhibition brings the allure of early Chinese civilization to life through sculptures, new media art, and interactive installations. [Extracted from the article]

The article discusses the urban regeneration efforts in the Fangzhuang community in Beijing. The community, which has a large elderly population, faced challenges such as aging infrastructure and limited access to services. To address these issues, the Fangzhuang Subdistrict Office initiated over 40 renewal projects, including the renovation of the Fangzhuang Cultural and Art Center and the transformation of an idle cinema into a nursing home. These efforts have revitalized the community and earned recognition at the Third Beijing Urban Regeneration Forum. Urban regeneration projects like these are being implemented nationwide in China to enhance physical, economic, and social conditions in urban areas. [Extracted from the article]

The 2024 World Robot Conference was held in Beijing from August 21 to 25. The conference showcased over 600 products from 169 companies, including 27 humanoid robots and more than 60 newly launched items. The event also featured a robot competition with over 13,000 contestants from various countries, focusing on technological advancements and talent development. The exhibition attracted a large audience interested in learning about the capabilities and applications of robots. [Extracted from the article]

During the summer vacation, students from Beijing's Daxing No.1 Middle School visited the Xiaolongmen National Forest Park to learn about the city's forest ecology. The visit was organized by the school, the Beijing Forest Ecosystem Research Station, and the Beijing Municipal Forestry and Parks Promotion Center. The students engaged in scientific exploration, learning about research methods and conducting field activities in the forest. They also had the opportunity to conduct hands-on field research under the guidance of scientists. This trip provided younger students with a unique and in-depth learning experience, and it is expected that similar activities will be held in the future to promote ecological education in Beijing. [Extracted from the article]

To eliminate the influence of the parameter mismatches and obtain high model quality, a model-free predictive current control (MF-PCC) strategy based on the autoregressive moving average (ARMA) structure is proposed in this article and applied to the permanent magnet synchronous motor (PMSM) speed control system. Since the ARMA model group, which is a family of mathematical models containing AR, MA, and ARMA structures, considers operating states within several sampling periods to achieve better model accuracy, the plant is online-designed as this type, and its coefficients are estimated according to the sampled data by the normalized least-mean-square (NLMS) algorithm with adaptive normalized step length to achieve improved model quality with reduced calculation burden. Compared with the ultralocal MF-PCC strategy, the advantages of better stator current quality and robustness are demonstrated by the experimental results, as well as the reduced calculation burden compared with the recursive least square (RLS) algorithm used to estimate the coefficients.

The performance of model predictive control has a strong correlation to the precision of the physical parameters of the plant, and these parameters are hard to determine since they are continuously changing during the operation process. To fully eliminate the influence of the physical parameters and enhance robustness, a model-free predictive control is proposed in this article to suit the electrical drive systems. The plant model is designed as several discrete-time transfer functions used to decouple the input and output signals and to describe their relationships, and the coefficients of these functions are online designed based on the recursive least square algorithm. An observer is designed to obtain accurately sampled current components considering the delays. The proposed method is applied to a permanent magnet synchronous motor speed control system as the stator current controller, and the simulation and experimental results show the advantages of the improved dynamics, stator current quality, and robustness compared with the conventional model-free predictive current control strategy.

Hepatocellular carcinoma (HCC) remains challenging due to the lack of efficient therapy. Promoting degradation of certain cancer drivers has become an innovative therapy. The nuclear transcription factor sine oculis homeobox 1 (SIX1) is a key driver for the progression of HCC. Here, we explored the molecular mechanisms of ubiquitination of SIX1 and whether targeting SIX1 degradation might represent a potential strategy for HCC therapy. Through detecting the ubiquitination level of SIX1 in clinical HCC tissues and analyzing TCGA and GEPIA databases, we found that ubiquitin specific peptidase 1 (USP1), a deubiquitinating enzyme, contributed to the lower ubiquitination and high protein level of SIX1 in HCC tissues. In HepG2 and Hep3B cells, activation of EGFR-AKT signaling pathway promoted the expression of USP1 and the stability of its substrates, including SIX1 and ribosomal protein S16 (RPS16). In contrast, suppression of EGFR with gefitinib or knockdown of USP1 restrained EGF-elevated levels of SIX1 and RPS16. We further revealed that SNS-023 (formerly known as BMS-387032) induced degradation of SIX1 and RPS16, whereas this process was reversed by reactivation of EGFR-AKT pathway or overexpression of USP1. Consequently, inactivation of the EGFR-AKT-USP1 axis with SNS-032 led to cell cycle arrest, apoptosis, and suppression of cell proliferation and migration in HCC. Moreover, we showed that sorafenib combined with SNS-032 or gefitinib synergistically inhibited the growth of Hep3B xenografts in vivo. Overall, we identify that both SIX1 and RPS16 are crucial substrates for the EGFR-AKT-USP1 axis-driven growth of HCC, suggesting a potential anti-HCC strategy from a novel perspective.

Single-atom catalysts (SACs) have recently attracted extensive attention attributed to their extremely high atom utilization and unique configuration. Meanwhile, high-temperature pyrolysis is indispensable for synthesizing metal and nitrogen-doped carbon catalysts. However, the rational design of SACs is hindered by the lack of understanding of evolutionary paths during pyrolysis due to uncontrollable factors. Here operandoX-ray absorption fine structure (XAFS) spectroscopy combined with comprehensive analysis under heating conditions was conducted to monitor the structural evolution of Co-NC formatting. The pyrolysis procedure of the CoCl2precursor to the Co-N4moiety was thoroughly identified by confirming two key turning points at 300 and 700 °C. These results demonstrate that temperature greatly affects structural changes during the formation of SACs, providing a new perspective for the controllable design and synthesis of high-performance SACs.

The 15th Beijing Olympic City Sports Culture Festival was held at the Olympic Park in Beijing to celebrate China's Fitness Day and the anniversary of the opening ceremony of the Beijing 2008 Olympic Summer Games. The event showcased various activities, including a 5-km cycling ride along Beijing's Central Axis, three-on-three basketball games, a street dance competition, and sport climbing. The festival aimed to highlight Beijing as a "dual Olympic city" that has hosted both Summer and Winter Olympics. [Extracted from the article]

An exhibition at the China National Arts and Crafts Museum in Beijing showcases nearly 160 clay figurines that depict the evolution of Chinese clothing over a span of more than 2,000 years. The figurines' attire is based on paintings and sculptures from major museums across China. The exhibition includes representations of clothing from various dynasties, such as the Qin and Han dynasties, the Sui Dynasty to the Five Dynasties period, the Yuan Dynasty, and the Tang Dynasty. Visitors can explore the different styles and fashions of each era. [Extracted from the article]

An exhibition on Chinese intangible cultural heritage protection is currently being held at the China National Arts and Crafts Museum in Beijing. The exhibition features over 600 objects related to both national and world heritage and allows visitors to personally engage with various intangible cultural heritage skills. Children particularly enjoy trying on lion heads used in lion dance performances and having their photos taken. The exhibition will be open until June 2025. [Extracted from the article]

More than 50 young people from 28 countries, including China, France, the United Kingdom, Japan, India, and Russia, gathered at the Huguang Guild Hall in Beijing to enjoy a cup of tea and a performance on the guqin, a traditional Chinese instrument. China's tea processing techniques and associated social practices were added to UNESCO's Representative List of the Intangible Cultural Heritage of Humanity in 2022. The event, cohosted by the Academy of Contemporary China and World Studies and the Information Office of Beijing Municipality, aimed to foster cultural exchange and ideas among young people from different countries. [Extracted from the article]

The article discusses the restoration and use of historic buildings in Beijing, specifically focusing on the Taianli Culture and Arts Center. The center is housed in a shikumen building, which is architecturally significant and rare in Beijing. Local authorities recognized the need for restoration and began the process in 2018. Today, the center is home to various establishments such as cafes, restaurants, museums, and galleries, and regularly hosts lectures and exhibitions on architecture and heritage preservation. The article includes photos showcasing the vibrant community space that Taianli has become. [Extracted from the article]

The article discusses a traditional Chinese painting exhibition at the Capital Museum in Beijing, which showcases the historic Central Axis of the city through the eyes of contemporary artists. The Central Axis is a symbolic line that runs through various significant landmarks, including Tiananmen Square, the Forbidden City, and Jingshan Park. The exhibition features 175 artworks by 90 painters from across China and will be open from June 8 to July 31. The article also includes colorful photographs of the paintings and notable landmarks along the Central Axis. [Extracted from the article]

The 26th Hortiflorexpo IPM Beijing, a premier professional expo for horticulture in China, took place at the China International Exhibition Center from May 23 to 25. The event, which was suspended for several years due to the COVID-19 pandemic, attracted over 700 exhibitors from more than 20 countries and regions. It showcased a variety of flowers, plants, and horticultural equipment, and included flower arrangement demonstrations, a conference on China's horticultural retail industry, and sharing sessions for online flower sellers. The event drew horticultural exhibitors, enthusiasts, and local residents, and the scale of the event and the number of visitors rebounded to prepandemic levels. [Extracted from the article]

Although the robustness is enhanced essentially by the model-free predictive control, the accuracy of its data-driven model is directly affected by the unnecessary current harmonics, such as the harmonics caused by the control strategy itself. To reduce the influences of these harmonics, a continuous-control-set model-free predictive fundamental current control (MF-PFCC) strategy is proposed in this article for the permanent magnet synchronous motor driving system. Harmonics due to the controller including side frequency effect and frequency coupling effect are analyzed in principle, and a frequency-converting double second-order generalized integrator structure is designed to exclude the fundamental terms from the sampled current to cut the coupling path of the effects and to improve the accuracy of the data-driven model in the MF-PFCC without any time-variable physical parameters. The analyses of the effects and the effectiveness of the proposed method are verified by experimental and supplementary simulation results, as well as advantages including the reduced influence of effects and enhanced robustness with improved stator current quality.

Sparse code multiple access (SCMA) and power-domain nonorthogonal multiple access (PDNOMA) have been considered for use with fifth-generation (5G) and beyond mobile communications, in order to increase the bandwidth efficiency, reduce the latency in terms of waiting for resources, and increase the numbers of connections. Existing codebook allocation schemes for SCMA and PDNOMA-SCMA systems consider only the physical layer. We propose an iterative cross-physical-and-application-layer codebook allocation for uplink video communications. We allocate the codebook according to the channel state information of the physical layer, and codebooks are exchanged among users to minimize the sum of the video mean square error in order to increase the average peak signal-to-noise ratio (PSNR). Furthermore, we propose a deep neural network (DNN) approach to reduce the computational complexity. We propose a novel postprocessing algorithm that is applied to the DNN output to ensure the constraints of codebook allocation are satisfied. Simulation results show that the proposed iterative PDNOMA-SCMA cross-layer codebook allocation scheme outperforms an existing scheme that uses only the physical layer by 1.27 dB in terms of PSNR (video quality) for 12 users, four subcarriers, and SNR = 21 dB. The proposed DNN-based approach has an execution time that is 67% lower than the proposed iterative PDNOMA-SCMA cross-layer codebook allocation scheme, at the cost of a performance degradation of 0.84 dB.

The transverse optical pumping (TOP) introduced by a probe beam can result in a polarization error in the output signal of a spin-exchange relaxation-free (SERF) co-magnetometer. In this article, a model capable of quantitatively evaluating TOP in a SERF co-magnetometer is established based on three characteristics of the probe beam. According to this model, a novel fast measurement method for TOP based on steady-state response output signals and longitudinal polarization information is proposed. Furthermore, a method of suppressing TOP based on counter-propagating beam is suggested, and the circular polarization-induced TOP is effectively reduced by finely adjusting the amount of phase retardation of an octantal waveplate. Eventually, the counter-propagating beam scheme achieves a 22.74% TOP suppression ratio. The stability of both the short- and long-term outputs of the SERF co-magnetometer is improved and the lowest point of the Allan variance is $0.006~^{\circ }$ /h better than the original. Moreover, the coupling effect between the probe beam power fluctuation and output signal bias of the SERF co-magnetometer is decreased.

Battery is the core equipment of the electrical vehicle (EV), battery life, and performance are critical to EV. Only motor variables are considered in most model predictive control (MPC) strategy in which battery indexes are neglected. A model predictive speed control (MPSC) strategy with adjustable C-rate of battery is proposed in this paper on EV with permanent magnet synchronous machine (PMSM). The rest capacity of battery is involved in the cost function, and the operating speed is related to the rest capacity of battery which adjusts the C-rate of the discharging currents further to protect battery. As the EV runs, the C-rate is decreased step by step according to the improved cost function, and the energy is saved to prolong mileage. The benefits of the proposed method including discharging capacities and operating mileage are corroborated by the simulation and repetitive experimental results under same conditions.

A Johann-type X-ray spectrometer was successfully developed at the hard X-ray branch (in-vacuum undulator with a 24-mm periodic length) of the energy material beamline (E-line) at the Shanghai Synchrotron Radiation Facility (SSRF). This spectrometer was utilized to implement X-ray emission spectroscopy (XES), high-energy resolution fluorescence-detected X-ray absorption spectroscopy (HERFD-XAS), and resonant inelastic X-ray scattering. Seven spherically bent crystals were positioned on the respective vertical 500-mm-diameter Rowland circles, adopting an area detector to increase the solid angle to 1.75%of 4 πsr, facilitating the study of low-concentrate systems under complex reaction conditions. Operated under the atmosphere pressure, the spectrometer covers the energy region from 3.5 to 18 keV, with the Bragg angle ranging from 73∘to 86∘during vertical scanning. It offers a promised energy resolution of sub-eV (XES) and super-eV (HERFD-XAS). Generally, these comprehensive core-level spectroscopy methods based on hard X-rays at the E-line with an extremely high photon flux can meet the crucial requirements of a green energy strategy. Moreover, they provide substantial support for scientific advances in fundamental research.

This article from Beijing Review discusses the daily routines of primary school students in Beijing, specifically focusing on Zhongguancun No.1 Primary School. The school, which has over 4,000 students, offers a variety of extracurricular courses and clubs for students to participate in. Additionally, the school organizes activities such as science and technology fairs, sports events, and art festivals to provide students with opportunities to showcase their talents. The article includes several photos showcasing different activities and events at the school. [Extracted from the article]

The National Museum of China in Beijing is currently hosting an exhibition on dragons, in celebration of the Year of the Dragon. The exhibition showcases dragon-related artifacts from the Neolithic Age to the early 20th century, made from materials such as bronze, jade, porcelain, gold, silver, and lacquerware. The highlight of the exhibition is a jade dragon from the Neolithic Hongshan culture, dating back 5,000-6,000 years, which is one of the earliest representations of a dragon found in China. Dragons have historically been a symbol of the monarch in ancient China and are still considered auspicious symbols of rain, good luck, and prosperity. [Extracted from the article]

In model predictive control (MPC) system for permanent magnet synchronous motor (PMSM), calculation delay of the strategy influences control performances seriously. A Smith structure-based model predictive current control (MPCC) strategy is proposed in this article. The cost function of MPCC is improved and the Smith structure is added to compensate calculation delay. Advantages such as speed ITAE, settling time, and stability compared with the conventional MPCC strategy under the same conditions are analyzed. The effectiveness and correctness of the proposed method are corroborated by the simulation and experimental results.

In order to investigate supply chain coordination and decision under customer balking and stochastic demand, the article considers a two-echelon supply chain consisting of one manufacturer with risk-neutral and one retailer with risk-neutral and develops two models in a centralized and a decentralized system and the three contracts are designed to coordinate supply chain and the optimal price and customer balking strategies are obtained. The results show that the revenue and cost-sharing contract can coordinate supply chain under customer balking and price-dependent demand and achieve the Pareto-improvement; the expected sales quantity and expected reduced sales quantity are influenced conversely by the threshold of inventory and probability of a sale under customer balking. In addition, numerical analysis is given to verify the effectiveness of revenue and cost-sharing contract and the paper gives some managerial insights and puts forward to the future work at last.

By analyzing the impact of different fairness concerns on a green supply chain, this study determines the optimal decisions under different power structures and conducts a comparative analysis of them. The findings of this study are summarized as follows: 1) under the manufacturer-dominated structure, retail price, wholesale price, product greenness, the manufacturer's profit, the total profit of the supply chain, the manufacturer's utility, and the retailer's utility are all negatively correlated with fairness concerns, but positively correlated with the retailer's profit; 2) under the retailer-dominated structure, fairness concerns have no impact on retail price, product greenness, or the total profit of the supply chain, are positively correlated with wholesale price and the manufacturer's profit and utility, and are negatively correlated with the retailer's profit and utility; 3) under the Nash equilibrium structure, fairness concerns have no impact on the green supply chain.

AbstractBackgroundRecent reports have demonstrated high troponin levels in patients affected with COVID-19. In the present study, we aimed to determine the association between admission and peak troponin levels and COVID-19 outcomes.MethodsThis was an observational multi-ethnic multi-centre study in a UK cohort of 434 patients admitted and diagnosed COVID-19 positive, across six hospitals in London, UK during the second half of March 2020.ResultsMyocardial injury, defined as positive troponin during admission was observed in 288 (66.4%) patients. Age (OR: 1.68 [1.49–1.88], p < .001), hypertension (OR: 1.81 [1.10–2.99], p = .020) and moderate chronic kidney disease (OR: 9.12 [95% CI: 4.24–19.64], p < .001) independently predicted myocardial injury. After adjustment, patients with positive peak troponin were more likely to need non-invasive and mechanical ventilation (OR: 2.40 [95% CI: 1.27–4.56], p = .007, and OR: 6.81 [95% CI: 3.40–13.62], p < .001, respectively) and urgent renal replacement therapy (OR: 4.14 [95% CI: 1.34–12.78], p = .013). With regards to events, and after adjustment, positive peak troponin levels were independently associated with acute kidney injury (OR: 6.76 [95% CI: 3.40–13.47], p < .001), venous thromboembolism (OR: 11.99 [95% CI: 3.20–44.88], p < .001), development of atrial fibrillation (OR: 10.66 [95% CI: 1.33–85.32], p = .026) and death during admission (OR: 2.40 [95% CI: 1.34–4.29], p = .003). Similar associations were observed for admission troponin. In addition, median length of stay in days was shorter for patients with negative troponin levels: 8 (5–13) negative, 14 (7–23) low-positive levels and 16 (10–23) high-positive (p < .001).ConclusionsAdmission and peak troponin appear to be predictors for cardiovascular and non-cardiovascular events and outcomes in COVID-19 patients, and their utilisation may have an impact on patient management.

The Meet You Museum in Beijing's 798 Art Zone is currently hosting a digital immersive exhibition focused on the Sanxingdui Site, a significant Bronze Age civilization in Guanghan, Sichuan Province, China. The exhibition combines sound, light, and image technologies to present the archaeological discoveries of the site, as well as the daily life, sacrificial culture, and belief system of the ancient Shu Kingdom. Visitors can experience large-scale scene simulation and restoration, view cultural relics, and engage in digital multimedia interaction. The exhibition, which includes a 360-degree circular theater showcasing restored images of the Sanxingdui Site, will be open until April 7. [Extracted from the article]

The Spring Festival travel rush, known as chunyun, is currently taking place in China. It is the largest annual human migration in the world, with an estimated 9 billion passenger trips expected over a 40-day period. Many people are traveling home to spend the festival with their loved ones, while others are heading to coastal holiday destinations in southern China for warmer weather. Cities like Xiamen and Shantou have seen an increase in tourists, with many exploring the neighborhoods on foot through the popular activity of "city walks." [Extracted from the article]