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Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil.engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY işıl SANRi KARAPiNAR Zehra N.KUTlU ismail.e.KiliÇ Department of Civil.engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vul.erability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inistanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vul.erability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vul.erability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vul.erability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is bel.eved to advance the current applications for vul.erability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vul.erability assessment cultural heritage local site effect

Cavitation research with computational fluid dynamics:From euler-euler to euler-lagrange approach

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Journal of Hydrodynamics 2024年第1期36卷 1-23页

作者： Bin Ji Zi-yang Wang Huai-yu cheng Rickard e.Bensow State Key laboratory of Water Resources engineering and Management Wuhan UniversityWuhan430072China Department of Mechanics and Maritime Sciences Chalmers University of TechnologyGothenburgSweden

Unsteady cavitating flow often contains vapor structures with a wide range of different length scales,from micro-bubbles to large cavities,which issues a big chal.enge to precisely investigate its evolution mechanism by computational fluid dynamics(CFD)*** present work reviews the development of simulation methods for cavitation,especially the emerging euler-lagrange ***,the progress of the numerical investigation of hot and vital issues is discussed,including cavitation inception,cloud cavitation inner structure and its formation mechanism,cavitation erosion,and cavitation *** is indicated that the euler-lagrange method can determine cavitation inception point *** cloud cavitation,the euler-lagrange method can reveal the source of microbubbles and their distribution law inside the shedding *** method also has advantages and great potential in assessing cloud cavitation-induced erosion and *** the ever-growing demands of cavitation simulation accuracy in basic research and engineering applications,how to improve the euler-lagrange method’s stability and applicability is still an open *** further promote the application of this advanced CFD simulation technology in cavitation research,some key issues are to be sol.ed and feasible suggestions are put forward for further work.

关键词： numerical simulation euler-euler method euler-lagrange method bubble dynamicsgy,Gothenburg,Sweden

A synthesis of the Cretaceous wildfire record related to atmospheric oxygen levels?

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Journal of Pal.eogeography 2024年第1期13卷 149-164页

作者： Da-Wei lü Wen-Xu Du Zhi-Hui Zhang Yuan Gao Tian-Tian Wang Jin-cheng Xu Ao-Cong Zhang cheng-Shan Wang Shandong Provincial Key laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Sciences and EngineeringShandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina School of earth Sciences and Resources China University of GeosciencesBejing 100083China institute of earth Sciences China University of Geosciences(Bejing)Beijing 100083China

The Cretaceous was a significant greenhouse period in earth's history with higher atmospheric CO_(2) levels and temperatures than today. Although evidence of combustion has been widely described from the Cretaceous deposits, our understanding of the spatiotemporal diversification pattern and process of the Cretaceous wildfires is still limited. in this study, we comprehensively synthesize a total of 271 published Cretaceous wildfire occurrences based on the by-products of burning, including fossil charcoal, pyrogenic inertinite(fossil charcoal in coal), and pyrogenic polycyclic aromatic hydrocarbons(PAHs). Spatially, the dataset shows a distinctive distribution of reported wildfire evidence characterized by high concentration in the middle latitudinal areas of the Northern Hemisphere(30°N-60°N) over the Cretaceous. Temporally, an overall increasing trend of the reported wildfire data from the early Cretaceous to the late Cretaceous is coincident with higher atmospheric O_(2) levels. However, the spatial and temporal patterns may result from many types of factors, such as taphonomy, preservation, and researcher biases, instead of a real picture of the Cretaceous wildfire evolution. To better understand the spatiotemporal diversification of the Cretaceous wildfire, more investigations on the record of wildfire occurrences during this period would be necessary in the future.

关键词： Wildfire Cretaceous Atmospheric oxygen Taphonomy Charcoal

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A bacterial protein Rhp-PSP inhibits plant viral proliferation through endoribonuclease activity

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Journal of integrative Agriculture 2024年第6期23卷 1967-1978页

作者： lijie Chen Qianze Peng Xiaohua Du Weixing Zhang Ju’e cheng Shu’e Sun Deyong Zhang Pin Su Yong liu longping Branch College of BiologyHunan UniversityChangsha 410082China State Key laboratory of Hybrid Rice/institute of Plant Protection Hunan Academy of Agricultural SciencesChangsha 410125China

Plant virus causes massive crop losses ***,there is currently no effective measure to control plant viral ***,we identify an antiviral protein Rhp-PSP,produced by the bacterial Rhodopseudomonas palustris strain *** this study,we discover that the antiviral activity of Rhp-PSP rel.es on its endoribonuclease *** the arginine(R)residue at position 129 onto alanine(A)abolishs its endoribonuclease activity on coat protein(CP)RNA of tobacco mosaic virus(TMV),consequentially,compromises the antiviral activity of *** investigation demonstrates that,the mutant Rhp-PSP^(R129A)is unable to form the homotrimer as the wild type,indicating the importance of quaternary junction for the endoribonuclease *** of Rhp-PSP in Nicotiana benthamiana significantly enhances the resistance against TMV of seedlings,while expression of Rhp-PSP^(R129A)did not,confirming that endoribonuclease activity is responsible for the antiviral activity of *** addition,foliar spray of Rhp-PSP solution on tomato and pepper plants significantly reduces the disease index of viral diseases,indicating that Rhp-PSP shows potential to develop antiviral agent in practice.

关键词： Rhodopseudomonas palustris Rhp-PSP tobacco mosaic virus endoribonuclease antiviral activity

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A historical review of hybrid rice breeding

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Journal of integrative Plant Biology 2024年第3期66卷 532-545页

作者： Xiaoming Zheng Fei Wei cheng cheng Qian Qian State Key laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Yazhouwan National laboratory Sanya City 572024China

The development of germplasm resources and advances in breeding methods have led to steady increases in yield and quality of rice (Oryza sativa l.). Three milestones in the recent history of rice breeding have contributed to these increases: dwarf rice breeding, hybrid rice breeding, and super rice breeding. On the 50th anniversary of the success of three-line hybrid rice,we highlight important scientific discoveries in rice breeding that were made by Chinese scientists and summarize the broader history of the field. We discuss the strategies that could be used in the future to optimize rice breeding further in the hope that China will continue to play a leading role in international rice breeding.

关键词： Chinese experience dwarf breeding hybrid rice breeding super rice breeding

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learning layout generation for virtual worlds

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Computational Visual Media 2024年第3期10卷 577-592页

作者： Weihao cheng Ying Shan ARC lab TencentShenzhen 518057China

The emergence of the metaverse has ledto the rapidly increasing demand for the generation ofextensive 3D worlds. We consider that an engagingworld is built upon a rational layout of multiple landuse areas (e.g., forest, meadow, and farmland). Tothis end, we propose a generative model of landuse distribution that learns from geographic *** model is based on a transformer architecturethat generates a 2D map of the land-use layout,which can be conditioned on spatial and semanticcontrols, depending on whether either one or bothare provided. This model.enables diverse layoutgeneration with user control and layout expansion byextending borders with partial inputs. To generatehigh-quality and satisfactory layouts, we devise ageometric objective function that supervises the modelto perceive layout shapes and regularize generationsusing geometric priors. Additionally, we devise aplanning objective function that supervises the modelto perceive progressive composition demands andsuppress generations deviating from controls. Toevaluate the spatial distribution of the generations, wetrain an autoencoder to embed land-use layouts intovectors to enable comparison between the real andgenerated data using the Wasserstein metric, which isinspired by the Fr´echet inception distance.

关键词： layout generation virtual worlds Transformer land-use

Blindness-free beam scanning antenna with array of array architecture: principle,design,and experiment

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Science China(information Sciences) 2024年第3期67卷 209-224页

作者： Jianxu SUN Yujian cheng School of electronic Science and engineering University of electronic Science and Technology of China

This paper presents a 66–76-GHz sparsely-excited phased array antenna with the array of array(Ao A) architecture for eliminating the blindness and suppressing the grating lobe when scanning. For the array antennas printed on the thick dielectric layers with high relative permittivity, scanning blindness appears and seriously impacts the radiation performance. To address this issue, the Ao A topology is developed first. it finds that the scanning blindness appears due to the coupling of the radiating Floquet modes to the non-radiating surface wave(SW) modes. Therefore, the array is divided into two types of domino *** inner-phase distributions are introduced into the domino subarrays to break the one-to-one relationship between the Floquet mode and the SW mode. Then, the blindness inside ±60° scanning volume is eliminated by the aperiodic subarrays. Meanwhile, the aperiodic inner-phase distributions enhance the aperiodicity of the array and contribute to suppressing the grating lobe when scanning. Next, the meta-surface-based dipole with the shorted post is chosen as the unit cell for the proposed aperiodic array. Based on these methods,the array achieves the wide-scanning performance of ±60° in the e-plane and ±30° in the H-plane, without the blindness and the grating lobe. Finally, the 16×16 array is built and simulated with the dimension of32 mm × 32 mm. At the highest operating frequency, the simulated gains are 28.42, 25.17, and 24.01 d Bi when scanning to the broadside, 50° in the e-plane, and 30° in the H-plane, respectively. Compared to the ideal gain, it shows that the simulated radiation efficiency is about 84.13%, 62.08%, and 35.23% when scanning to the broadside, 50° in the e-plane, and 30° in the H-plane, respectively. The worst transmission coefficient, i.e., the worst isolation, is-11.97 d B between the central.element and its two adjacent elements in the e-plane. The array prototypes are fabricated, and the experiments are carried out to ver

关键词： 6G communication systems phased array AoA aperiodic subarray wideband wide-scanning surface-wave scanning blindness grating lobe

SARS-CoV-2 and innate immunity:the good,the bad,and the"goldilocks"

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Cellular & Molecular immunology 2024年第2期21卷 171-183页

作者： Benjamin l.Sievers Mark T.K.cheng Kata Csiba Bo Meng Ravindra K.Gupta Department of Medicine University of CambridgeCambridgeUK Cambridge institute of Therapeutic immunology&infectious Disease(CiTiD) Department of MedicineUniversity of CambridgeCambridgeUk

An ancient conflict between hosts and pathogens has driven the innate and adaptive arms of *** about this interplay can not only help us identify biological mechanisms but also reveal pathogen vul.erabilities that can be leveraged *** humoral response to SARS-CoV-2 infection has been the focus of intense research,and the role of the innate immune system has received significantly less ***,we review current knowledge of the innate immune response to SARS-CoV-2 infection and the various means SARS-CoV-2 employs to evade innate defense *** also consider the role of innate immunity in SARS-CoV-2 vaccines and in the phenomenon of long COViD.

关键词： SARS-CoV-2 innate immune response interferon Cytokines inflammation Antiviral targets

“Capture-activation-recapture” mechanism-guided design of double-atom catalysts for electrocatalytic nitrogen reduction

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Journal of energy Chemistry 2024年第9期96卷 437-447页

作者： cheng He Shiqi Yan Wenxue Zhang State Key laboratory for Mechanical Behavior of Materials School of Materials Science1nd EngineeringXi’an Jiaotong UniversityXi’an 710049ShaanxiChina School of Materials Science1nd engineering Chang’an UniversityXi’an 710064ShaanxiChina

Compared with the traditional industrial nitrogen fixation, electrocatalytic methods, especially those utilizing double-atom catalysts containing nonmetals, can give good consideration to the economy and environmental protection. However, the existing “acceptance-donation” mechanism is only applicable to bimetallic catalysts and nonmetallic double-atom catalysts containing boron atoms. Herein, a novel “capture-activation-recapture” mechanism for metal-nonmetal double-atom catalyst is proposed to sol.e the problem by adjusting the coordination environments of nonmetallic atoms and utilizing the activation effect of metal atoms on nitrogen. Based on this mechanism, the nitrogen reduction reaction (NRR) activity of 48 structures is calculated by density functional theory calculation, and four candidates are selected as outstanding electrocatalytic nitrogen reduction catalysts: Si-Fe@NG (U_(l) = –0.14 V), Si-Co@NG (U_(l)= –0.15 V), Si-Mo@BP1 (U_(l) = 0 V), and Si-Re@BP1 (U_(l) = –0.02 V). The analyses of electronic properties further confirm “capture-activation-recapture” mechanism and suggest that the difference in valence electron distribution between metal and Si atoms triggers the activation of N≡N bonds. in addition, a machine learning approach is utilized to generate an expression and an intrinsic descriptor that considers the coordination environment to predict the limiting potential. This study offers profound insight into the synergistic mechanism of TM and Si for NRR and guidance in the design of novel double-atom nitrogen fixation catalysts.

关键词： "Capture-activation-recapture"mechanism Double-atom catalyst Nitrogen reduction reaction Density functional theory