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The Multi-parameter Test of Gravitational Wave Dispersion with Principal Component Analysis

Research in Astronomy and Astrophysics 2024年第5期24卷 140-150页

作者： Zhi-Chu Ma Rui niu Wen Zhao CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

In this work, we consider a conventional test of gravitational wave(GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity(GR)along the propagation of GWs. But different from tests conventionally performed previously, we vary multiple deformation coefficients simultaneously and employ the principal component analysis(PCA) method to remedy the strong degeneracy among deformation coefficients and obtain informative posteriors. The dominant PCA components can be better measured and constrained, and thus are expected to be more sensitive to potential departures from the waveform model. Using this method we analyze ten selected events and get the result that the combined posteriors of the dominant PCA parameters are consistent with GR within 99.7% credible intervals. The standard deviation of the first dominant PCA parameter is three times smaller than that of the original dispersion parameter of the leading order. However, the multi-parameter test with PCA is more sensitive to not only potential deviations from GR but also systematic errors of waveform models. The difference in results obtained by using different waveform templates hints that the demands of waveform accuracy are higher to perform the multiparameter test with PCA. Whereas, it cannot be strictly proven that the deviation is indeed and only induced by systematic errors. It requires more thorough research in the future to exclude other possible reasons in parameter estimation and data processing.

关键词： gravitational waves-gravitation-black hole physics

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A Study on the Impact of Chemical Structure on the Evolution of Aggregate Structure in Fiber-shaped High Density Polyethylene Vitrimer

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Chinese Journal of Polymer Science 2024年第10期42卷 1557-1565,I0013页

作者： Bing Wang Yuan-Chu Gao Hai Wang Hui niu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian116024China

Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shaped HDPE vitrimers through a reaction extrusion and post-drawing *** chemical structure characterization,morphology observation,thermal and mechanical properties investigation,as well as aggregate structure analysis,this work revealed the influence of dynamic bonds on the formation of aggregate structures during fiber-shaped vitrimers processing.A small amount of dynamic bonds in HDPE restricts the motion of PE chain during melt-extruding and post-drawing,resulting in a lower orientation of the PE ***,lamellar growth and fibril formation during post-drawing at high temperature are enhanced to some extent due to the competition between dynamic bond and chain *** uneven morphology of fibershaped HDPE vitrimers can be attributed to the stronger elastic effect brought by dynamic bonding,which plays a more dominant role in determining the mechanical properties of fiber-shaped vitrimers compared to aggregate *** Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shap

关键词： High density polyethylene vitrimer Fiber-shaped Aggregate structures Transesterification reaction

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中国与世界主要含油气区大地构造比较分析

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地质学报 2006年第10期80卷 1491-1492,1493-1500,I0001-I0004页

作者：任纪舜邓平肖藜薇牛宝贵王军中国地质科学院地质研究所北京100037

中国与世界主要含油气区比较,区别十分明显。世界主要为海相,特别是中新生代海相含油气层系,一般经历了单旋回的演化过程;中国主要为中新生代陆相含油气层系,经历了多旋回的演化过程。世界主要含油气区,大多位于南(冈瓦纳)、北(劳亚)大... 详细信息

中国与世界主要含油气区比较,区别十分明显。世界主要为海相,特别是中新生代海相含油气层系,一般经历了单旋回的演化过程;中国主要为中新生代陆相含油气层系,经历了多旋回的演化过程。世界主要含油气区,大多位于南(冈瓦纳)、北(劳亚)大陆的本部或被动边缘,大陆被大洋环绕,形成洋环陆的古构造-古地理景观,各时代海相沉积发育良好,构造动力体系单一,地质结构比较简单,含油气层系保存条件比较优越。而中国所在的东亚大陆,则属南(冈瓦纳)、北(劳亚)两个巨型大陆之间的转换构造域,它是由众多微陆和造山带组合而成的复合大陆,古构造-古地理环境为洋含陆,即微陆散布在浩瀚的海洋之中;古亚洲洋、特提斯-古太平洋、大西洋/印度洋-太平洋三大动力体系的叠加、复合,使东亚成为全球构造最复杂的地区。因此,在中国,只有在构造上相对稳定,又被中新生代沉积覆盖的塔里木、四川、鄂尔多斯等多旋回叠合盆地,海相油气层系才得以保存,在海相地层直接暴露地表的地区,至今尚未发现具有工业价值的油气藏。

关键词：中国世界石油天然气大地构造

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RNA interference in insects:the link between antiviral defense and pest control

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Insect Science 2024年第1期31卷 2-12页

作者： Jinzhi niu Ruoyu Chen Jin-Jun Wang Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionSouthwest UniversityChongqingChina Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River(Ministry of Education) Southwest UniversityChongqingChina

RNA interference(RNAi)is a form of gene silencing triggered by double-stranded RNA(dsRNA)that operates in all eukaryotic *** has been widely investigated in insects to determine the underlying molecular mechanism,to investigate its role in systemic antiviral defense,and to develop strategies for pest *** insect cells are infected by viruses,viral dsRNA signatures trigger a local RNAi response to block viral replication and generate virus-derived DNA that confers systemic ***-based insect pest control involves the application of exogenous dsRNA targeting genes essential for insect development or survival,but the efficacy of this approach has limited potency in many pests through a combination of rapid dsRNA degradation,inefficient dsRNA uptake/processing,and ineffective RNAi *** could be addressed by dsRNA screening and evaluation,focusing on dsRNA design and off-target management,as well as dsRNA production and *** review summarizes recent progress to determine the role of RNAi in antiviral defense and as a pest control strategy in insects,addressing gaps between our fundamental understanding of the RNAi mechanism and the exploitation of RNAi-based pest control strategies.

关键词： RNAi response systemic RNAi insecticidal dsRNA biological control off-targets

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秦岭地区陡岭—小茅岭隆起带西段几个岩体的SHRIMP锆石U-Pb测年及其地质意义

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地质论评 2006年第6期52卷 826-835页

作者：牛宝贵和政军任纪舜王军邓平中国地质科学院地质研究所北京100037

通过对南秦岭与中秦岭之间陡岭—小茅岭隆起构造—岩浆岩带西段柞水—镇安—山阳之间的磨沟峡、黑沟和冷水沟等岩体的锆石U-Pb定年研究,获得磨沟峡闪长岩年龄743±12Ma、黑沟碱性花岗岩年龄686±10Ma、冷水沟辉长岩年龄680±9Ma;侵入冷... 详细信息

通过对南秦岭与中秦岭之间陡岭—小茅岭隆起构造—岩浆岩带西段柞水—镇安—山阳之间的磨沟峡、黑沟和冷水沟等岩体的锆石U-Pb定年研究,获得磨沟峡闪长岩年龄743±12Ma、黑沟碱性花岗岩年龄686±10Ma、冷水沟辉长岩年龄680±9Ma;侵入冷水沟辉长岩的正长闪长斑岩年龄141.7±1.4Ma,确定这些岩体形成时代分别为新元古代中、晚期和早白垩世初。岩石化学分析结果表明,新元古代中、晚期岩体形成于大陆裂解环境,较早期的磨沟峡闪长岩,岩石地球化学具板内花岗岩的特征;较晚期的冷水沟和黑沟岩体,由超基性—基性岩和偏碱性花岗岩组成,具非造山双模式岩浆岩组合特征。侵入冷水沟辉长岩的正长闪长斑岩为高K-钙碱性岩浆岩,具后造山花岗岩的地球化学特征。新元古代岩浆岩为古中国地台裂解的产物,燕山期正长闪长岩则代表秦岭多旋回造山最终完成的时代。

关键词：古中国地台秦岭侵入岩锆石 U—Pb定年裂解

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Information Conductivity:Universal Performance Measure for Semantic Communications

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China Communications 2024年第7期21卷 17-36页

作者： Liang Zijian niu Kai Zhang Ping Key Laboratory of Universal Wireless Communications Ministry of Education(Beijing University of Posts and Telecommunications)Beijing 100876China Peng Cheng Laboratory Shenzhen 518055China State Key Laboratory of Networking and Switching Technology(Beijing University of Posts and Telecommunications) Beijing 100876China

As a novel paradigm,semantic communication provides an effective solution for breaking through the future development dilemma of classical communication ***,it remains an unsolved problem of how to measure the information transmission capability for a given semantic communication method and subsequently compare it with the classical communication *** this paper,we first present a review of the semantic communication system,including its system model and the two typical coding and transmission methods for its *** address the unsolved issue of the information transmission capability measure for semantic communication methods,we propose a new universal performance measure called Information *** provide the definition and the physical significance to state its effectiveness in representing the information transmission capabilities of the semantic communication systems and present elaborations including its measure methods,degrees of freedom,and progressive *** results in image transmission scenarios validate its practical applicability.

关键词： information conductivity information transmission capability semantic communications system model universal performance measure

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SETD2 in cancer:functions,molecular mechanisms,and therapeutic regimens

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Cancer Biology & Medicine 2024年第9期21卷 725-730页

作者： Yawen Weng Jing Xue Ningning niu State Key Laboratory of Systems Medicine for Cancer Stem Cell Research CenterRen Ji HospitalShanghai Cancer InstituteShanghai Jiao Tong University School of MedicineShanghai 200127China

In recent years,the histone methyltransferase SET domain containing 2(SETD2)has garnered significant attention for its involvement in *** we aim to summarize the research advances regarding SETD2 in tumors,elucidate the role in global epigenetic regulation,highlight potential therapeutic regimens for patients with SETD2 deficiency,and outline future research directions.

关键词： SETD2 regimen therapeutic

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Evaluation of arsenic pollution in field-contaminated soil at the soil’s actual pH

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Journal of Environmental Sciences 2024年第10期144卷 137-147页

作者： Tiancong Gao Haixia Tian Huimin niu Mallavarapu Megharaj Wenxiang He College of Natural Resources and Environment Northwest A&F UniversityKey Laboratory of Plant Nutrition and Agro-environment in Northwest ChinaMinistry of AgricultureYanglingShaanxi 712100China Global Centre for Environmental Remediation College of EngineeringScience and EnvironmentUniversity of NewcastleCallaghanNSW 2308Australia

The pollution and ecological risks posed by arsenic(As)entering the soil are the major environmental challenges faced by human *** phosphatase can serve as a useful indicator for assessing As contamination under specific soil pH ***,the study of phosphatase kinetics in long-term field As-contaminated soil remains unclear,presenting a significant obstacle to the monitoring and evaluation of As pollution and *** purpose of this study was to determine phosphatase activity and explore enzyme kinetics in soils subjected to long-term field As *** revealed that the soil phosphatase activity varied among the tested soil samples,depending on the concentrations of *** relationship between total As,As fractions and phosphatase activity was found to be significant through negative exponential function *** parameters,including maximum reaction velocity(Vmax),Michaelis constant(Km)and catalytic efficiency(V_(max)/K_(m)),ranged from 3.14×10^(−2)–53.88×10^(−2) mmol/(L·hr),0.61–7.92 mmol/L,and 0.46×10^(−2)–11.20×10^(−2) hr−1,*** and Vmax/Km of phosphatase decreased with increasing As pollution,while Km was less ***,Vmax/Km showed a significant negative correlationwith all As fractions and total *** ecological doses(ED10)for the complete inhibition and partial inhibition models ranged from0.22–70.33 mg/kg and 0.001–55.27 mg/kg,respectively,indicating that V_(max)/K_(m) can be used as an index for assessing As pollution in field-contaminated *** study demonstrated that the phosphatase kinetics parameters in the soil’s pH system were better indicators than the optimal pH for evaluating the field ecotoxicity of As.

关键词： Arsenic pollution Ecological risk Soil phosphatase Enzyme kinetics Catalytic efficiency(V_(max)/K_(m))

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Nonlinear constitutive models of rock structural plane and their applications

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 790-806页

作者： Wenlin Feng Shuangjian niu Chunsheng Qiao Dujian Zou School of Civil and Environmental Engineering Harbin Institute of TechnologyShenzhenChina Shenzhen Municipal Engineering Corporation Shenzhen518000China School of Civil Engineering Beijing Jiaotong UniversityBeijing100044China

Structural planes play an important role in controlling the stability of rock engineering,and the influence of structural planes should be considered in the design and construction process of rock *** this paper,mechanical properties,constitutive theory,and numerical application of structural plane are studied by a combination method of laboratory tests,theoretical derivation,and program *** test results reveal the change laws of various mechanical parameters under different roughness and normal *** the pre-peak stage,a non-stationary model of shear stiffness is established,and threedimensional empirical prediction models for initial shear stiffness and residual stage roughness are *** nonlinear constitutive models are established based on elasto-plastic mechanics,and the algorithms of the models are developed based on the return mapping *** to a large number of statistical analysis results,empirical prediction models are proposed for model parameters expressed by structural plane characteristic ***,the discrete element method(DEM)is chosen to embed the constitutive models for practical *** running programs of the constitutive models have been compiled into the discrete element model *** comparison results between the proposed model and the Mohr-Coulomb slip model show that the proposed model can better describe nonlinear changes at different stages,and the predicted shear strength,peak strain and shear stiffness are closer to the test *** research results of the paper are conducive to the accurate evaluation of structural plane in rock engineering.

关键词： Structural plane Engineering stability Roughness Normal stress Elasto-plastic constitutive model Discrete element method

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Effects of surface energy and substrate on modulus determination of biological films by conical indentation

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Science China(Technological Sciences) 2024年第6期67卷 1757-1764页

作者： DING Yue LI Cheng-Ya niu XinRui WANG Gang-Feng Department of Engineering Mechanics SVLXi’an Jiaotong UniversityXi’an710049China Department of Mechanical Engineering City University of Hong KongHong Kong SAR999077China

Micro-/nano-indentation has become prevalent in evaluating the mechanical characteristics of biological samples,such as cells and ***,the existing contact models describing conical indentation ignore the joint effects of surface energy and substrate,and consequently cannot accurately extract the Young's modulus of biological samples deposited on *** finite element methods,we examine the conical indentation of biological films on substrates while taking surface energy into *** on the dimensional analysis,the explicit relationship between load and indentation depth is achieved for films with their moduli varying from 0.001 to 100 times that of the *** the classical Sneddon's model was employed to analyze the load-depth data,the measured modulus could reach 18 times the real modulus for films on harder substrates,but only 4%of the real modulus for films on softer ***,in micro-/nano-indentations,neglecting the contribution of surface energy would result in an overestimation of the Young's modulus of films depending on the contact *** analytical expression provided here can be utilized to precisely deduce the mechanical characteristics of biological films deposited on substrate from the load and indentation depth data of a conical indentation.

关键词： biological film surface effect substrate effect indentation

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