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China Ocean Engineering 2024年第2期38卷 297-312页

作者： ZHANG Yi CHEN Yue YUN Lai liang xu Ocean College Zhejiang UniversityZhoushan 316000China Hainan Institute Zhejiang UniversitySanya 572000China

This paper aims to enhance the compression capacity of underwater cylindrical shells by adopting the corrugated sandwich structure of *** cuttlebone suffers uniaxial external compression,while underwater cylindrical shells are in a biaxial compressive stress *** suit the biaxial compressive stress state,a novel bidirectional corrugated sandwich structure is proposed to improve the bearing capacity of cylindrical *** static and buckling analysis for the sandwich shell and the unstiffened cylindrical shell with the same volume-weight ratio are studied by numerical *** is indicated that the proposed sandwich shell can effectively reduce the ratio between circumferential and axial stress from 2 to 1.25 and improve the critical buckling load by about 1.63 *** simulation shows that optimizing and adjusting the structural parameters could significantly improve the advantage of the sandwich ***,the hydrostatic pressure tests for shell models fabricated by 3D printing are carried *** to the experimental results,the overall failure position of the sandwich shell is at the center part of the sandwich *** has been found the average critical load of the proposed sandwich shell models exceeds two times that of the unstiffened shell ***,the proposed bio-inspired bidirectional corrugated sandwich structure can significantly enhance the pressure resistance capability of cylindrical shells.

关键词： bio-inspiration bidirectional corrugation sandwich shell external pressure buckling

Structure design of lead-free chiral-polar perovskites for sensitive self-powered X-ray detection

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Chinese Journal of Structural Chemistry 2024年第6期43卷 34-39页

作者： Xin Dong Tianqi Chen jing liang Lei Wang Huajie Wu Zhijin xu Junhua Luo Li-Na Li State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou350108China University of the Chinese Academy of Sciences Beijing100039China

Metal halide perovskites have made significant progress in X-ray detection owing to their exceptional optoelec-tronic ***,most of these materials suffer from toxic element lead and require for high operating ***,it is imperative to explore environmentally friendly perovskite crystals without external bias for X-ray ***,we strategically introduce chiral cations to synthesize a pair of lead-free chiral-polar hybrid perovskites(S-MPz)_(6)Bi_(3)I_(21)·6H_(2)O and(R-MPz)_(6)Bi_(3)I_(21)·6H_(2)O(1S and 1R,S/R-MPz=S/R-2-methylpipera-zinium),which exhibit strong circular dichroism(CD)signals with an anisotropic g-factor reaching approximately ***,the chiral-polar feature gives rise to distinctive spontaneous polarization,which leads to a photovoltage of 1.1 V under X-ray illumination,endowing self-powered detection capabilities for *** exploration of X-ray devices based on 1R single crystal(SC)demonstrates a high sensitivity of 5.2 pC Gy_(air)^(-1)cm^(-2)at zero *** study realizes passive X-ray detection depending on the intrinsic spontaneous polarization induced built-in electric field of chiral-polar perovskite,providing an effective approach to the chemical design of desired materials for high-performance"green"self-powered radiation detection.

关键词： Lead-free perovskite Self-powered Chiral-polar X-ray detection

Quantitative Analysis of Frosting Characteristics on the Drip Tray of A Cryogenic Valve for LNG Ships

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China Ocean Engineering 2024年第4期38卷 572-585页

作者： BAI xu CHEN Guan-yu DU Yue xu Cao CHEN Jia-jing School of Naval Architecture&Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Cryogenic valves play a crucial role in the production and transportation of liquefied natural gas(LNG),and are primarily responsible for efficiently controlling the inflow and outflow of LNG and regulating ***,due to their operation in low-temperature and high-humidity environments,crucial components such as drip trays are susceptible to frosting,which may lead to LNG leakage,thereby causing severe safety *** this study,the user-defined function(UDF)is employed to redevelop Fluent,which integrates the frost growth model with the Eulerian multiphase flow model,to conduct a quantitative analysis of frosting on drip trays of cryogenic *** effects of environmental parameters,such as wind speed,ambient temperature,air humidity,and cold surface temperature on the growth of the frost layer were *** study reveals a limiting wind speed between 1 m/s and 2 m/*** reaching this limit speed,the growth of the frost layer reaches its maximum,and further increases in the wind speed have no significant effect on the growth of the frost ***,the influence of the change in the flow field on droplet impingement and freezing during the growth of the frost layer is considered through the coupling method of the kinematic characteristics of water droplets and the collection coefficient of water *** study identifies the influence of different parameters on the droplet impact efficiency,leading to the modification of the frost layer on the drip tray.

关键词： LNG carrier drip tray frost effective impact coefficient

On the Infinite-Dimensional Modular Lie Superalgebras of O-Type

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Algebra Colloquium 2024年第2期31卷 347-360页

作者： Xiaoning xu jing Zhao Yucai Su School of Mathematics and Statistics Liaoning UniversityShenyang 110036China 不详

The natural filtrations of infinite-dimensional Lie superalgebras of O-type over a field of positive characteristic are proved to be invariant under automorphisms by studying ad-nilpotent *** observe that two Lie superalgebras of O-type are isomorphic if and only if the integers in the definition of these Lie superalgebras are ***,all the Lie superalgebras of O-type are classified in the sense of isomorphism.

关键词： filtration isomorphism classification

A Knowledge-enhanced Two-stage Generative Framework for Medical Dialogue Information Extraction

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Machine Intelligence Research 2024年第1期21卷 153-168页

作者： Zefa Hu Ziyi Ni jing Shi Shuang xu Bo xu School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Institute of Automation Chinese Academy of SciencesBeijing 100190China

This paper focuses on term-status pair extraction from medical dialogues(MD-TSPE),which is essential in diagnosis dia-logue systems and the automatic scribe of electronic medical records(EMRs).In the past few years,works on MD-TSPE have attracted increasing research attention,especially after the remarkable progress made by generative ***,these generative methods output a whole sequence consisting of term-status pairs in one stage and ignore integrating prior knowledge,which demands a deeper un-derstanding to model the relationship between terms and infer the status of each *** paper presents a knowledge-enhanced two-stage generative framework(KTGF)to address the above *** task-specific prompts,we employ a single model to com-plete the MD-TSPE through two phases in a unified generative form:We generate all terms the first and then generate the status of each generated *** this way,the relationship between terms can be learned more effectively from the sequence containing only terms in the first phase,and our designed knowledge-enhanced prompt in the second phase can leverage the category and status candidates of the generated term for status ***,our proposed special status"not mentioned"makes more terms available and en-riches the training data in the second phase,which is critical in the low-resource *** experiments on the Chunyu and CMDD datasets show that the proposed method achieves superior results compared to the state-of-the-art models in the full training and low-re-sourcesettings.

关键词： Medical dialogue understanding information extraction text generation knowledge-enhanced prompt low-resource setting dataaugmentation

EjGASA6 promotes flowering and root elongation by enhancing gibberellin biosynthesis

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Journal of Integrative Agriculture 2024年第5期23卷 1568-1579页

作者： Qian Chen Shunyuan Yong Fan xu Hao Fu Jiangbo Dang Qiao He Danlong jing Di Wu Guolu liang Qigao Guo Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River(Ministry of Education)/College of Horticulture and Landscape Architecture Southwest UniversityChongqing 400715China State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University/Academy of Agricultural Sciences of Southwest University Chongqing 400715China College of Agronomy and Biotechnology Southwest UniversityChongqing 400715China

The Gibberellic Acid-stimulated Arabidopsis(GASA)gene family is involved in the regulation of gene expression and plant growth,development,and stress *** investigate the function of loquat GASA genes in the growth and developmental regulation of plants,a loquat EjGASA6 gene homologous to Arabidopsis AtGASA6 was ***6 expression was induced by gibberellin,and ectopic transgenic plants containing this gene exhibited earlier bloom and longer primary roots since these phenotypic characteristics are related to higher gibberellin *** analysis and qRT-PCR results showed that the expression levels of GA3ox1 and GA20ox1,which encode key enzymes in gibberellin biosynthesis,were significantly ***,we confirmed that EjGASA6 could promote the expression of GA20ox1 via the luciferase reporter ***,our results suggest that EjGASA6 promotes blooming and main-root elongation by positively regulating gibberellin *** findings broaden our understanding of the role of GASAs in plant development and growth,and lay the groundwork for future research into the functions of EjGASA6 in regulating loquat growth and development.

关键词： loquat EjGASA6 gibberellin synthesis biological function

Geometry characteristics and wide temperature behavior of silicon-based GaN surface acoustic wave resonators with ultrahigh quality factor

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Science China(Information Sciences) 2024年第2期67卷 267-278页

作者： Guofang YU Renrong liang Haiming ZHAO Lei XIAO Jie CUI Yue ZHAO Wenpu CUI jing WANG Jun xu Jun FU Tianling REN School of Integrated Circuits Tsinghua University Beijing National Research Center for Information Science Technology Tsinghua University

Surface acoustic wave(SAW) resonators with an ultrahigh Q-factor are designed and fabricated on silicon-based gallium nitride(GaN/Si). The temperature-dependent performance is characterized over a wide range, from 10 to 500 K. Finite element analysis is employed to guide the design of the SAW resonator from indications of the Rayleigh mode and weak propagation direction dependence of SAW in the c-plane of GaN/Si. The SAW resonator with 100 pairs of interdigital transducers(IDT), 100 pairs of grating reflectors(GR) for each side, aperture size of 80 μm, metallization ratio of 0.5, and electrode width of 500 nm resonates at 1.9133 GHz accordingly with an ultrahigh Q-factor of 7622 at room temperature, which contributes the fr× Qr, up to 14.583×1012Hz. A resonator operating over 10 to 500 K indicates an approximately linear decreasing temperature dependence above 280 K while being approximately constant below 40 K. The fitting to resonator characteristics using the modified Butterworth Van Dyke(m BVD) model reveals a reduction in both the electrode and mechanical losses while worsening the dielectric loss with cooling down.

关键词： GaN/Si SAW resonator ultrahigh Q-factor temperature-dependent performance mBVD losses

Transverse mode-coupling instability with longitudinal impedance

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Nuclear Science and Techniques 2024年第6期35卷 40-53页

作者： Hai-Sheng xu Chun-Tao Lin Na Wang jing-Ye xu Yuan Zhang Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Institute of Advanced Science Facilities Shenzhen 518107GuangdongChina

Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle *** mechanism of TMCI can be explained by the coupling of transverse coherent oscillation modes owing to the transverse short-range wakefield(i.e.,the transverse broadband impedance).Recent studies on future circular colliders,e.g.,FCC-ee,showed that the threshold of TMCI decreased significantly when both longitudinal and transverse impedances were *** performed computations for the circular electron-positron collider(CEPC)and observed a similar *** studies on the influence of longitudinal impedance on the TMCI threshold were *** concluded that the imaginary part of the longitudinal impedance,which caused a reduction in the incoherent synchrotron tune,was the primary reason for the reduction in the TMCI ***,the real part of the longitudinal impedance assists in increasing the TMCI threshold.

关键词： Transverse mode-coupling instability Longitudinal impedance

The Forecast Skills and Predictability Sources of Marine Heatwaves in the NUIST-CFS1.0 Hindcasts

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Advances in Atmospheric Sciences 2024年第8期41卷 1589-1600页

作者： jing MA Haiming xu Changming DONG jing-Jia LUO Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/KLME/ILCEC/Institute of Climate and Application Research(ICAR) Nanjing University of Information Science and TechnologyNanjingJiangsu 210044China

Using monthly observations and ensemble hindcasts of the Nanjing University of Information Science and Technology Climate Forecast System(NUIST-CFS1.0) for the period 1983–2020, this study investigates the forecast skill of marine heatwaves(MHWs) over the globe and the predictability sources of the MHWs over the tropical oceans. The MHW forecasts are demonstrated to be skillful on seasonal-annual time scales, particularly in tropical oceans. The forecast skill of the MHWs over the tropical Pacific Ocean(TPO) remains high at lead times of 1–24 months, indicating a forecast better than random chance for up to two years. The forecast skill is subject to the spring predictability barrier of El Nino-Southern Oscillation(ENSO). The forecast skills for the MHWs over the tropical Indian Ocean(TIO), tropical Atlantic Ocean(TAO), and tropical Northwest Pacific(NWP) are lower than that in the TPO. A reliable forecast at lead times of up to two years is shown over the TIO, while a shorter reliable forecast window(less than 17 months) occurs for the TAO and ***, the forecast skills for the TIO, TAO, and NWP are seasonally dependent. Higher skills for the TIO and TAO appear in boreal spring, while a greater skill for the NWP emerges in late summer-early autumn. Further analyses suggest that ENSO serves as a critical source of predictability for MHWs over the TIO and TAO in spring and MHWs over the NWP in summer.

关键词： marine heatwaves NUIST-CFS1.0 hindcasts forecast skill predictability source ENSO

Neglected Mendelian causes of stroke in adult Chinese patients who had an ischaemic stroke or transient ischaemic attack

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Stroke & Vascular Neurology 2024年第3期9卷 194-201,I0001-I0103页

作者： Wei Li Hao Li Chaoxia Lu Jialu Zhao Huichun xu Zhe xu Braxton Mitchell Yong Jiang Hong-Qiu Gu Qin xu Anxin Wang Xia Meng Jinxi Lin jing jing Zixiao Li Wanlin Zhu Zhigang liang Mengxing Wang Yongjun Wang China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Division of Endocrinology Diabetes and NutritionDepartment of MedicineUniversity of Maryland School of MedicineBaltimoreMarylandUSA Department of Neurology Qindao University Medical College Affiliated Yantai Yuhuangding HospitalYantaiShandongChina Clinical Center for Precision Medicine in Stroke Capital Medical UniversityBeijingChina

Background and purpose Multiple factors play important roles in the occurrence and prognosis of ***,the roles of monogenic variants in all-cause ischaemic stroke have not been systematically *** aim to identify underdiagnosed monogenic stroke in an adult ischaemic stroke/transient ischaemic attack(TIA)cohort(the Third China National Stroke Registry,CNSR-III).Methods Targeted next-generation sequencing for 181 genes associated with stroke was conducted on DNA samples from 10428 patients recruited through *** genetic and clinical data from electronic health records(EHRs)were reviewed for completion of the diagnostic *** assessed the percentages of individuals with pathogenic or likely pathogenic(P/LP)variants,and the diagnostic yield of pathogenic variants in known monogenic disease genes with associated *** In total,1953 individuals harboured at least one P/LP variant out of 10428 ***,792(7.6%)individuals(comprising 759 individuals harbouring one P/LP variant in one gene,29 individuals harbouring two or more P/LP variants in different genes and 4 individuals with two P/LP variants in ABCC6)were predicted to be at risk for one or more monogenic diseases based on the inheritance ***,230 of 792 individuals manifested a clinical phenotype in the EHR data to support the diagnosis of stroke with a monogenic *** most diagnosed Mendelian cause of stroke in the cohort was cerebral autosomal dominant arteriopathy with subcortical infarcts and *** were no relationships between age or family history and the incidence of first symptomatic monogenic stroke in *** The rate of monogenic cause of stroke was 2.2%after reviewing the clinical *** reasons that Mendelian causes of stroke may be missed in adult patients who had an ischaemic stroke/TIA include a late onset of stroke symptoms,combination with common vascular risks and the absence of a promine

关键词： patients transient likely