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Macroscopic model and statistical model to characterize electromagnetic information of a digital coding metasurface

National Science Review 2024年第3期11卷 159-171页

作者： Rui Wen Shao Jun Wei Wu Zheng Xing Wang Hui Xu Han Qing Yang Qiang Cheng Tie Jun Cui Institute of Electromagnetic Space Southeast University State Key laboratory of Millimeter Waves Southeast University Peng Cheng laboratory Pazhou laboratory(Huangpu)

A digital coding metasurface is a platform connecting the digital space and electromagnetic wave space, and has therefore gained much attention due to its intriguing value in reshaping wireless channels and realizing new communication architectures. Correspondingly, there is an urgent need for electromagnetic information theory that reveals the upper limit of communication capacity and supports the accurate design of metasurface-based communication systems. To this end, we propose a macroscopic model and a statistical model of the digital coding metasurface. The macroscopic model uniformly accommodates both digital and electromagnetic aspects of the meta-atoms and predicts all possible scattered fields of the digital coding metasurface based on a small number of simulations or measurements. Full-wave simulations and experimental results show that the macroscopic model is feasible and accurate. A statistical model is further proposed to correlate the mutual coupling between meta-atoms with covariance and to calculate the entropy of the equivalent currents of digital coding metasurface. These two models can help reconfigurable intelligent surfaces achieve more accurate beamforming and channel estimation, and thus improve signal power and coverage. Moreover, the models will encourage the creation of a precoding codebook in metasurface-based direct digital modulation systems, with the aim of approaching the upper limit of channel capacity. With these two models, the concepts of current space and current entropy, as well as the analysis of information loss from the coding space to wave space, is established for the first time, helping to bridge the gap between the digital world and the physical world, and advancing developments of electromagnetic information theory and new-architecture wireless systems.

关键词： electromagnetic information theory current entropy current space digital coding metasurface macroscopic model statistical model

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Bioinspired 3D flexible devices and functional systems

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National Science Review 2024年第3期11卷 271-295页

作者： Xu Cheng Zhangming Shen Yihui Zhang Applied Mechanics laboratory Department of Engineering Mechanics Tsinghua University laboratory of Flexible Electronics Technology Tsinghua University

Flexible devices and functional systems with elaborated three-dimensional(3D) architectures can endow better mechanical/electrical performances, more design freedom, and unique functionalities, when compared to their two-dimensional(2D) counterparts. Such 3D flexible devices/systems are rapidly evolving in three primary directions, including the miniaturization, the increasingly merged physical/artificial intelligence and the enhanced adaptability and capabilities of heterogeneous integration.Intractable challenges exist in this emerging research area, such as relatively poor controllability in the locomotion of soft robotic systems, mismatch of bioelectronic interfaces, and signal coupling in multi-parameter sensing. By virtue of long-time–optimized materials, structures and processes, natural organisms provide rich sources of inspiration to address these challenges, enabling the design and manufacture of many bioinspired 3D flexible devices/systems. In this Review, we focus on bioinspired 3D flexible devices and functional systems, and summarize their representative design concepts, manufacturing methods, principles of structure-function relationship and broad-ranging applications. Discussions on existing challenges, potential solutions and future opportunities are also provided to usher in further research efforts toward realizing bioinspired 3D flexible devices/systems with precisely programmed shapes,enhanced mechanical/electrical performances, and high-level physical/artificial intelligence.

关键词： bioinspired designs biomimetic 3D structures 3D flexible electronics 3D functional systems direct 3D manufacture 2D-to-3D assembly

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laboratory studies on the infectivity of human respiratory viruses:Experimental conditions,detections,and resistance to the atmospheric environment

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Fundamental Research 2024年第3期4卷 471-483页

作者： Yaohao Hu Shuyi Peng Bojiang Su Tao Wang Juying Lin Wei Sun Xiaodong Hu Guohua Zhang Xinming Wang Ping'an Peng Xinhui Bi State Key laboratory of Organic Geochemistry and Guangdong Provincial Key laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China Guangdong-Hong Kong-Macao Joint laboratory for Environmental Pollution and Control Guangzhou 510640China

The environmental stability of infectious viruses in the laboratory setting is crucial to the transmission potential of human respiratory viruses.Different experimental techniques or conditions used in studies over the past decades have led to diverse understandings and predictions for the stability of viral infectivity in the atmospheric environment.In this paper,we review the current knowledge on the effect of simulated atmospheric conditions on the infectivity of respiratory viruses,mainly focusing on influenza viruses and coronaviruses,including severe acute respiratory syndrome coronavirus 2 and Middle East respiratory syndrome coronavirus.First,we summarize the impact of the experimental conditions on viral stability;these involve the methods of viral aerosol generation,storage during aging and collection,the virus types and strains,the suspension matrixes,the initial inoculum volumes and concentrations,and the drying process.Second,we summarize and discuss the detection methods of viral infectivity and their disadvantages.Finally,we integrate the results from the reviewed studies to obtain an overall understanding of the effects of atmospheric environmental conditions on the decay of infectious viruses,especially aerosolized viruses.Overall,this review highlights the knowledge gaps in predicting the ability of viruses to maintain infectivity during airborne transmission.

关键词： Respiratory viruses Viral infectivity laboratory simulation Atmospheric environmental condition Airborne transmission

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Micelle-directed self-assembly of single-crystal-like mesoporous stoichiometric oxides for high-performance lithium storage

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National Science Review 2024年第4期11卷 195-205页

作者： Yanhua Wan Changyao Wang Xingmiao Zhang Yang Yin Mengmeng Liu Bing Ma Linlin Duan Yuzhu Ma Wei Zhang Changlin Zheng Dongliang Chao Fei Wang Yongyao Xia Wei Li Department of Chemistry Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials State Key Laboratory of Molecular Engineering of Polymers College of Chemistry and Materials ScienceFudan University State Key laboratory of Surface Physics and Department of Physics Fudan University

Due to their uncontrollable assembly and crystallization process,the synthesis of mesoporous metal oxide single crystals remains a formidable challenge.Herein,we report the synthesis of single-crystal-like mesoporous Li2TiSiO5by using soft micelles as templates.The key lies in the atomic-scale self-assembly and step-crystallization processes,which ensure the formation of single-crystal-like mesoporous Li2TiSiO5microparticles via an oriented attachment growth mechanism under the confinement of an in-situ formed carbon matrix.The mesoporous Li2TiSiO5anode achieves a superior rate capability(148 mAh g-1at5.0 A g-1) and outstanding long-term cycling stability(138 mAh g-1after 3000 cycles at 2.0 A g-1) for lithium storage as a result of the ultrafast Li+diffusion caused by penetrating mesochannels and nanosized crystal frameworks（5-10 nm）.In comparison,bulk Li2TiSiO5exhibits poor rate capability and cycle performance due to micron-scale diffusion lengths.This method is very simple and reproducible,heralding a new way of designing and synthesizing mesoporous single crystals with controllable frameworks and chemical functionalities.

关键词： mesoporous materials micelles single-crystal-like Li2TiSiO5 lithium-ion batteries

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Functional genomics of Brassica napus:Progresses,challenges,and perspectives

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Journal of Integrative Plant Biology 2024年第3期66卷 484-509页

作者： Zengdong Tan Xu Han Cheng Dai Shaoping Lu Hanzi He Xuan Yao Peng Chen Chao Yang Lun Zhao Qing-Yong Yang Jun Zou Jing Wen Dengfeng Hong Chao Liu Xianhong Ge Chuchuan Fan Bing Yi Chunyu Zhang Chaozhi Ma Kede Liu Jinxiong Shen Jinxing Tu Guangsheng Yang Tingdong Fu Liang Guo Hu Zhao National Key laboratory of Crop Genetic Improvement Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhan 430070China Yazhouwan National laboratory Sanya 572025China

Brassica napus,commonly known as rapeseed or canola,is a major oil crop contributing over 13%to the stable supply of edible vegetable oil worldwide.Identification and understanding the gene functions in the B.napus genome is crucial for genomic breeding.A group of genes controlling agronomic traits have been successfully cloned through functional genomics studies in B.napus.In this review,we present an overview of the progress made in the functional genomics of B.napus,including the availability of germplasm resources,omics databases and cloned functional genes.Based on the current progress,we also highlight the main challenges and perspectives in this field.The advances in the functional genomics of B.napus contribute to a better understanding of the genetic basis underlying the complex agronomic traits in B.napus and will expedite the breeding of high quality,high resistance and high yield in B.napus varieties.

关键词： accelerate breeding Brassica napus functional genomics high resistance high yield

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Conversion of a single-layer ANN to photonic SNN for pattern recognition

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Science China(Information Sciences) 2024年第1期67卷 261-270页

作者： Yanan HAN Shuiying XIANG Tianrui ZHANG Yahui ZHANG Xingxing GUO Yuechun SHI State Key laboratory of Integrated Service Networks State Key Discipline Laboratory of Wide Bandgap Semiconductor TechnologyXidian University Yongjiang laboratory

This work presents a complete conversion scheme for photonic spiking neural networks(SNNs).We verified that the output of an artificial neural network(ANN) trained with the simulated optical activation function can be directly converted into the spike rate of a photonic spiking neuron model.To reveal the feasibility of hardware implementation,we considered the effects of different bit precisions of data and weight,noise level,and bias current mismatch on the converted results.The proposed scheme was evaluated using the Deterding vowel,IRIS,TIDIGITS,and MNIST datasets for pattern recognition,and achieved mean accuracies of 95.80%,98.67%,96.19%,and 92.33%,respectively.The proposed scheme can convert an ANN into a photonic SNN with almost no precision loss,and the performance was comparable to that of an ANN trained with the rectified linear unit function.The proposed scheme can enable the high-performance implementation of photonic SNNs.

关键词： photonic SNN conversion optical computing pattern recognition artificial neural network

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PDK1 promotes breast cancer progression by enhancing the stability and transcriptional activity of HIF-1α

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Genes & Diseases 2024年第4期11卷 353-367页

作者： Yu Wei Dian Zhang He Shi Husun Qian Hongling Chen Qian Zeng Fangfang Jin Yan Ye Zuli Ou Minkang Guo Bianqin Guo Tingmei Chen Key laboratory of Clinical laboratory Diagnostics(Ministry of Education) College of Laboratory MedicineChongqing Medical UniversityChongqing 400016China Chongqing Key laboratory of Translational Research for Cancer Metastasis and Individualized Treatment Chongqing University Cancer HospitalChongqing 400030China

Pyruvate dehydrogenase kinase 1(PDK1)phosphorylates the pyruvate dehydroge-nase complex,which inhibits its activity.Inhibiting pyruvate dehydrogenase complex inhibits the tricarboxylic acid cycle and the reprogramming of tumor cell metabolism to glycolysis,which plays an important role in tumor progression.This study aims to elucidate how PDK1 pro-motes breast cancer progression.We found that PDK1 was highly expressed in breast cancer tissues,and PDK1 knockdown reduced the proliferation,migration,and tumorigenicity of breast cancer cells and inhibited the HIF-1α(hypoxia-inducible factor 1a)pathway.Further investigation showed that PDK1 promoted the protein stability of HIF-1αby reducing the level of ubiquitination of HIF-1a.The HIF-1αprotein levels were dependent on PDK1 kinase activity.Furthermore,HIF-1a phosphorylation at serine 451 was detected in wild-type breast cancer cells but not in PDK1 knockout breast cancer cells.The phosphorylation of HIF-1αat Ser 451 stabilized its protein levels by inhibiting the interaction of HIF-1a with von Hippel-Lindau and prolyl hydroxylase domain.We also found that PDK1 enhanced HIF-1αtranscriptional ac-tivity.In summary,PDK1 enhances HIF-1αprotein stability by phosphorylating HIF-1a at Ser451 and promotes HIF-1αtranscriptional activity by enhancing the binding of HIF-1αto P300.PDK1 and HIF-1a form a positive feedback loop to promote breast cancer progression.

关键词： Breast cancer HIF-1α PDK1 Protein phosphorylation Transcriptional activity

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Improving error-correcting capability in DNA digital storage via soft-decision decoding

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National Science Review 2024年第2期11卷 135-144页

作者：丁璐璐伍世刚候志浩李阿伦许亚苹冯虎潘玮华阮珏 Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural Sciences Guangdong Provincial Key laboratory of Plant Molecular Breeding State Key Laboratory for Conservation and Utilization of Subtropical Agro-BioresourcesSouth China Agricultural University

Error-correcting codes(ECCs) employed in the state-of-the-art DNA digital storage(DDS) systems suffer from a trade-off between error-correcting capability and the proportion of redundancy. To address this issue, in this study, we introduce soft-decision decoding approach into DDS by proposing a DNA-specific error prediction model and a series of novel strategies. We demonstrate the effectiveness of our approach through a proof-of-concept DDS system based on Reed-Solomon(RS) code, named as Derrick. Derrick shows significant improvement in error-correcting capability without involving additional redundancy in both in vitro and in silico experiments, using various sequencing technologies such as Illumina, Pac Bio and Oxford Nanopore Technology(ONT). Notably, in vitro experiments using ONT sequencing at a depth of 7× reveal that Derrick, compared with the traditional hard-decision decoding strategy, doubles the error-correcting capability of RS code, decreases the proportion of matrices with decoding-failure by 229-fold, and amplifies the potential maximum storage volume by impressive 32 388-fold. Also, Derrick surpasses ‘state-of-the-art' DDS systems by comprehensively considering the information density and the minimum sequencing depth required for complete information recovery. Crucially, the soft-decision decoding strategy and key steps of Derrick are generalizable to other ECCs' decoding algorithms.

关键词： DNA digital storage (DDS) error-correcting code (ECC) soft-decision decoding error-correcting capability storage volume

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Brain circuits for retching-like behavior

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National Science Review 2024年第1期11卷 145-160页

作者： Lifang Huo Zhimin Ye Meiling Liu Ziqing He Meizhu Huang Dapeng Li Qian Wu Qian Wang Xiaoqun Wang Peng Cao Ji Dong Congping Shang School of Basic Medical Sciences Guangzhou National Laboratory The Fifth Afflliated Hospital Guangzhou Medical University Bioland laboratory (Guangzhou Regenerative Medicine and Health Guangdong laboratory) Department of Neurobiology School of Basic Medical Sciences Beijing Key Laboratory of Neural Regeneration and Repair Advanced Innovation Center for Human Brain Protection Capital Medical University State Key laboratory of Cognitive Neuroscience and Learning IDG/McGovern Institute for Brain Research Beijing Normal University Changping Life Science laboratory National Institute of Biological Sciences

Nausea and vomiting are important defensive responses to cope with pathogens and toxins that invade the body. The nucleus of the solitary tract(NTS) is important for initiating these responses. However, the molecular heterogeneities and cellular diversities of the NTS occlude a better understanding of these defensive responses. Here, we constructed the single-nucleus transcriptomic atlas of NTS cells and found multiple populations of NTS neurons that may be involved in these defensive responses. Among these, we identified Calbindin1-positive(Calb1+) NTS neurons that are molecularly distinct from Tac1+neurons.These Calb1+neurons are critical for nausea and retching induced by cereulide; an emetic toxin secreted by Bacillus Cereus. Strikingly, we found that cereulide can directly modulate vagal sensory neurons that innervate Calb1+NTS neurons, a novel mechanism distinct from that for nausea and retching induced by Staphylococcal enterotoxin A. Together, our transcriptomic atlas of NTS neurons and the functional analyses revealed the neural mechanism for cereulide-induced retching-like behavior. These results demonstrate the molecular and cellular complexities in the brain that underlie defensive responses to the diversities of pathogens and toxins.

关键词： vomiting nausea nucleus of the solitary tract Calbindin1 neural circuits

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Epigenetic control on transcription of vernalization genes and whole-genome gene expression profile induced by vernalization in common wheat

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Plant Diversity 2024年第3期46卷 386-394页

作者： Yunzhen Li Liujie Jin Xinyu Liu Chao He Siteng Bi Sulaiman Saeed Wenhao Yan National Key laboratory of Crop Genetic Improvement Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhan 430070China

Vernalization is necessary for winter wheat to flower.However,it is unclear whether vernalization is also required for spring wheat,which is frequently sown in fall,and what molecular mechanisms underlie the vernalization response in wheat varieties.In this study,we examined the molecular mechanisms that regulate vernalization response in winter and spring wheat varieties.For this purpose,we determined how major vernalization genes(VRN1,VRN2,and VRN3)respond to vernalization in these varieties and whether modifications to histones play a role in changes in gene expression.We also identified genes that are differentially regulated in response to vernalization in winter and spring wheat varieties.We found that in winter wheat,but not in spring wheat,VRN1 expression decreases when returned to warm temperature following vernalization.This finding may be associated with differences between spring and winter wheat in the levels of tri-methylation of lysine 27 on histone H3(H3K27me3)and tri-methylation of lysine 4 on histone H3(H3K4me3)at the VRN1 gene.Analysis of winter wheat transcriptomes before and after vernalization revealed that vernalization influences the expression of several genes,including those involved in leucine catabolism,cysteine biosynthesis,and flavonoid biosynthesis.These findings provide new candidates for further study on the mechanism of vernalization regulation in wheat.

关键词： Wheat Vernalization VRN1 Histone modification Regulate network

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