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Zero-density Estimates for Automorphic L-functions

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Acta Mathematica Sinica,English Series 2009年第6期25卷 945-960页

作者： De yu zhang School of Mathematical Sciences Shandong Normal University Ji'nan 250014 P. R. China

In this paper we prove zero-density estimates of the large sieve type for the automorphic L-function L（s, f × χ）, where f is a holomorphic cusp form and χ（mod q） is a primitive character.

关键词： cusp form L-function zero-density

Metabolic and transcriptomic analyses elucidate a novel insight into the network for biosynthesis of carbohydrate and secondary metabolites in the stems of a medicinal orchid Dendrobium nobile

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Plant Diversity 2023年第3期45卷 326-336页

作者： yu-Wen zhang yu-Cen Shi Shi-Bao zhang Key Laboratory of Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina yunnan Key Laboratory for Wild Plant Resources Kunming 650201YunnanChina University of Chinese Academy of Sciences Beijing 100049China Lijiang Forest Biodiversity National Observation and Research Station Kunming Institute of BotanyChinese Academy of SciencesLijiang 674100YunnanChina

Dendrobium nobile is an important medicinal and nutraceutical *** the ingredients of *** have been identified as polysaccharides,alkaloids,amino acids,flavonoids and bibenzyls,our understanding of the metabolic pathways that regulate the synthesis of these compounds is ***,we used transcriptomic and metabolic analyses to elucidate the genes and metabolites involved in the biosynthesis of carbohydrate and several secondary metabolites in the stems of ***.A total of 1005 metabolites and 31,745 genes were detected in the stems of *** majority of these metabolites and genes were involved in the metabolism of carbohydrates(fructose,mannose,glucose,xylulose and starch),while some were involved in the metabolism of secondary metabolites(alkaloids,β-tyrosine,ferulic acid,4-hydroxybenzoate and chrysin).Our predicted regulatory network indicated that five genes(AROG,PYK,DXS,ACEE and HMGCR) might play vital roles in the transition from carbohydrate to alkaloid *** analysis identified that six genes(ALDO,PMM,BGLX,EGLC,XYLB and GLGA) were involved in carbohydrate metabolism,and two genes(ADT and CYP73A) were involved in secondary metabolite *** analyses also indicated that phosphoenol-pyruvate(PEP) was a crucial bridge that connected carbohydrate to alkaloid *** regulatory network between carbohydrate and secondary metabolite biosynthesis established will provide important insights into the regulation of metabolites and biological systems in Dendrobium species.

关键词： Dendrobium nobile Transcriptome Metabolome Polysaccharides Alkaloids Secondary metabolite biosynthesis

U-Pb zircon geochronology of basaltic pyroclastic rocks from the basement beneath the Xisha Islands in the northwestern South China Sea and its geological significance

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Acta Oceanologica Sinica 2024年第2期43卷 83-93页

作者： yu zhang Kefu yu Shiying Li Guangxi Laboratory on the Study of Coral Reefs in the South China Sea Guangxi UniversityNanning 530004China Coral Reef Research Center of China Guangxi UniversityNanning 530004China School of Marine Sciences Guangxi UniversityNanning 530004China Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of ScienceGuangzhou 510301China

As one of the micro-blocks dispersed in the South China Sea(SCS), the basement of the Xisha Islands has rarely been drilled because of the thick overlying Cenozoic sediments, which has led to a confused understanding of the pre-Cenozoic basement of the Xisha Islands. Well CK-1, a kilometer-scale major scientific drill in the Xisha Islands in the northwestern SCS, penetrated thick reefal limestone(0–888.4 m) and the underlying basement rocks(888.4–901.4 m). In this study, we present the zircon U-Pb ages of basement basaltic pyroclastic rocks from Well CK-1 in the Xisha Islands of the northwestern SCS to investigate the basement nature of the Xisha microblock. The basement of Well CK-1 consists of basaltic pyroclastic rocks on the seamount. The zircon grains yielded apparent ages ranging from ca. 2 138.9 Ma to ca. 36 Ma. The old group of zircon grains from Well CK-1 was considered to be inherited zircons. Two Cenozoic zircons gave a weighted mean 206Pb/238U age of(36.3 ± 1.1) Ma,Mean Squared Weighted Deviations(MSWD) = 1.2, which may represent the maximum age of the volcano eruption. The Yanshanian inherited zircons(116.9–105.7 Ma and 146.1–130.2 Ma) from Well CK-1 are consistent with the zircons from Well XK-1, indicating that the basement of Chenhang Island may be similar to that of Well XK-1. We propose that the Xisha micro-block may have developed on a uniform Late Jurassic metamorphic crystalline basement, intruded by Cretaceous granitic magma.

关键词： South China Sea Xisha Islands basaltic pyroclastic rocks zircon

Florigen trafficking integrates photoperiod and temperature signals in Arabidopsis^FA

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Journal of Integrative Plant Biology 2020年第9期62卷 1385-1398页

作者： Lu Liu yu zhang Hao yu School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China Department of Biological Sciences National University of SingaporeSingapore 117543Singapore Temasek Life Sciences Laboratory National University of SingaporeSingapore 117604Singapore

The transition to flowering is the most dra-matic phase change in flowering plants and is crucial for reproductive success. A complex regulatory network in plants has evolved to perceive and integrate the endog-enous and environmental signals. These signals perceived, including day length and temperature, converge to regu-late FLOWERING LOCUS T (FT), which encodes a mobile stimulus required for floral induction in Arabidopsis. Despite the discovery of modulation of FT messenger RNA (mRNA) expression by ambient temperature, whether the trafficking of FT protein is controlled in response to changes in growth temperature is so far unknown. Here, we show that FT transport from companion cells to sieve elements is controlled in a temperature-dependent manner. This process is mediated by multiple C2 domain and transmembrane region proteins (MCTPs) and a soluble N-ethylmaleimide-sensitive factor protein attach-ment protein receptor (SNARE). Our findings suggest that ambient temperatures regulate both FT mRNA expression and FT protein trafficking to prevent precocious flowering at low temperatures and ensure plant reproductive suc-cess under favorable environmental conditions.

关键词： integrate ambient traffic

Beamforming Optimization for RIS-Aided SWIPT in Cell-Free MIMO Networks

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China Communications 2021年第9期18卷 175-191页

作者： Ziyi Yang yu zhang School of Information and Electronics Beijing Institute of TechnologyBeijing 100086China

Reconfigurable intelligent surface(RIS)is a promising technology that utilizes massive low-cost elements to reflect incident signals to desired *** this paper,we consider a RIS-aided cell free multiple-input multiple-output(MIMO)network that composed of multiple access points(APs),multiple RISs,multiple information receivers(IRs),and multiple energy receivers(ERs).Under the maximum transmit power constraints of the APs and the minimum total energy harvesting power constraints of the ERs,we aim to maximize the weighted sum-rate(WSR)by jointly optimizing the beamforming matrices and the passive RIS reflection ***,the formulated problem is nonconvex and very challenging to ***,we propose an alternating optimization algorithm to obtain a suboptimal ***,the proposed algorithm decomposes the original optimization problem into three subproblems that can be efficiently *** overcome the nonconvexity of the subproblems,a successive convex approximation(SCA)based algorithm is proposed to tackle the energy harvesting ***,an alternating direction method of multipliers(ADMM)based algorithm is proposed to optimize the constant modulus constrained RIS reflecting ***,simulations are conducted to demonstrate the performance advantages of the proposed algorithms.

关键词： cell-free networks SWIPT Reconfigurable intelligent surface SCA ADMM

Coupled simulation of fluid-particle interaction for large complex granules:A resolved CFD-DEM method for modelling the airflow in a vertical fixed bed of irregular sinter particles

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Particuology 2024年第7期90卷 292-306页

作者： Chengzhi Li yu zhang Jiahe Shen Wei zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan 430063China Centre for Bulk Solids and Particulate Technologies The University of NewcastleCallaghan NSW 2308Australia

A resolved CFD-DEM method is proposed to simulate the fluid-particle interaction for large complex *** airflow in a vertical sinter fixed bed is numerically studied using this *** multi-sphere clumped method is used to create irregular sinter particles in *** immersed boundary method and dynamic cell refinement are applied to describe the fluid flow around particles with higher resolution,by which the fluid-particle interaction can be simulated more *** simulation results presented the packing voidage distributions and the airflow fields in the sinter beds of different single and mixed particle size *** bed pressure drops were simulated and the results were compared with the corresponding experimental *** good agreement indicated that the proposed resolved CFD-DEM method is an effective tool to model the fluid-particle interaction for irregular large granules in the gas-solid multi-phase systems.

关键词： Resolved CFD-DEM method Irregular sinter particles Multi-sphere clumped method Immersed boundary method Dynamic cell refinement

Kill two birds with one stone: A novel dual-functional nanobiomaterial platform with a clear translational potential for bone regeneration

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Nano Research 2020年第9期13卷 2311-2312页

作者： yu Shrike zhang Zhiyuan zhang Division of Engineering in Medicine Department of MedicineBrigham and Womens HospitalHarvard Medical SchoolCambridgeMA02139USA Department of Oral and Maxillofacial Surgery Ninth Peoples HospitalShanghai Jiao Tong UniversityShanghai 200011China

Modulating healing of the bone has been a long-standing theme of both fundam ental and clinical research,which can be greatly aided using a biomaterials approach[1],designed to provide effective cues that are otherwise intrinsically lacking or insufficient in the wounded bone *** in Nano Research,Ye,Khademhosseini,and colleagues report a new nanobiom aterial strategy based on m esoporous silica rods with cone-shaped pores(MSR-CP),to minimize inflammation while maximizing regeneration,for the treatm ent of bone defects[2].

关键词： healing wound otherwise

A Scheme for Generating Nonisospectral Integrable Hierarchies and Its Related Applications

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Acta Mathematica Sinica,English Series 2021年第5期37卷 707-730页

作者： yu Feng zhang Xiang Zhi zhang School of Mathematics China University of Mining and TechnologyXuzhou 221116P.R.China

Under the framework of the complex column-vector loop algebra C^(p),we propose a scheme for generating nonisospectral integrable hierarchies of evolution equations which generalizes the applicable scope of the Tu *** applications of the scheme,we work out a nonisospectral integrable Schrodinger hierarchy and its expanding integrable *** latter can be reduced to some nonisospectral generalized integrable Schrodinger systems,including the derivative nonlinear Schrodinger equation once obtained by Kaup and ***,we obtain the famous Fokker-Plank equation and its generalized form,which has extensive applications in the stochastic dynamic ***,we investigate the Lie group symmetries,fundamental solutions and group-invariant solutions as well as the representation of the tensor of the Heisenberg group H_(3)and the matrix linear group SL(2,R)for the generalized Fokker-Plank equation(GFPE).

关键词： Nonisospectral integrable Schr?dinger hierarchy expanding integrable model symmetry group

Reliability analysis of carbon fiber rod-reinforced umbilical cable under tension using an improved sampling method

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Petroleum Science 2024年第4期21卷 2769-2778页

作者： yu zhang Hong-yu zhang Ran Xia Si-Ao Jiang Fang Wang College of Safety and Ocean Engineering China University of PetroleumBeijing102249China China Academy of Aerospace Aerodynamics China Aerospace Science and Technology GroupBeijing100094China College of Engineering Science and Technology Shanghai Ocean UniversityShanghai201306China

The umbilical cable is a vital component of subsea production systems that provide power,chemical agents,control signals et al.,and its requirement for reliability is exceedingly ***,as the umbilical cable is a composite structure comprising multiple functional units,the reliability analysis of such cables involves numerous parameters that can impact calculation *** this paper,the reliability analysis of a new kind of umbilical cable with carbon fiber rod under tension is *** global dynamic analytical model is first established to determine the maximum tension load,then the local analytical model of umbilical cable including each unit are constructed by finite element method(FEM).Based on the mechanical analytical model,the reliability of umbilical cable under tension load is studied using response surface method(RSM)and Monte Carlo *** the calculation process,a new tangent plane sampling method to calculate the response surface function(RSF)is proposed in this paper,which could make sampling points faster come close to the RSF curve,and it is proved that the calculation efficiency increases about 33%comparing with traditional method.

关键词： Umbilical cable Carbon fiber rod Failure analysis Response surface method Reliability