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Study of baryon number transport dynamics and strangeness conservation effects using Ω-hadron correlations
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作者 Wei-Jie Dong Xiao-Zhou Yu +4 位作者 Si-Yuan Ping Xia-Tong Wu Gang Wang Huan-Zhong Huang Zi-Wei Lin 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第7期147-156,共10页
In nuclear collisions at RHIC energies, an excess of Ω hyperons over ■ is observed, indicating that Ω has a net baryon number despite s and s quarks being produced in pairs. The baryon number in Ω may have been tr... In nuclear collisions at RHIC energies, an excess of Ω hyperons over ■ is observed, indicating that Ω has a net baryon number despite s and s quarks being produced in pairs. The baryon number in Ω may have been transported from the incident nuclei and/or produced in the baryon-pair production of Ω with other types of anti-hyperons such as Ξ. To investigate these two scenarios, we propose to measure the correlations between Ω and K and between Ω and anti-hyperons. We use two versions, the default and string-melting, of a multiphase transport(AMPT) model to illustrate the method for measuring the correlation and to demonstrate the general shape of the correlation. We present the Ω-hadron correlations from simulated Au+Au collisions at ■ =7.7 and 14.6 Ge V and discuss the dependence on the collision energy and on the hadronization scheme in these two AMPT versions. These correlations can be used to explore the mechanism of baryon number transport and the effects of baryon number and strangeness conservation on nuclear collisions. 展开更多
关键词 Baryon number transport Strangeness conversation correlation Gluon junction
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Dynamics of Non-Markovianity, Quantum Correlations and Information Scrambling of Three Qubits Systems Interacting via Rashba Interaction
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作者 Nasser Metwally Fawzeya Ebrahim 《Journal of Quantum Information Science》 CAS 2024年第2期52-67,共16页
The behavior of the quantum correlations, information scrambling and the non-Markovianity of three entangling qubits systems via Rashba is discussed. The results showed that, the three physical quantities oscillate be... The behavior of the quantum correlations, information scrambling and the non-Markovianity of three entangling qubits systems via Rashba is discussed. The results showed that, the three physical quantities oscillate between their upper and lower bounds, where the number of oscillations increases as the Rashba interaction strength increases. The exchanging rate of these three quantities depends on the Rashba strength, and whether the entangled state is generated via direct/indirect interaction. Moreover, the coherence parameter can be used as a control parameter to maximize or minimize the three physical quantities. 展开更多
关键词 Markovianity correlations Rashba Interaction Scrambling Information
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Evaluation of frictional pressure drop correlations for air-water and air-oil two-phase flow in pipeline-riser system
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作者 Nai-Liang Li Bin Chen 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1305-1319,共15页
Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to ... Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to pipeline-riser flow needs evaluation since the flow condition in pipeline-riser is quite different from the original data where they were derived from. In the present study, a comprehensive evaluation of 24prevailing correlation in predicting frictional pressure drop is carried out based on experimentally measured data of air-water and air-oil two-phase flows in pipeline-riser. Experiments are performed in a system having different configuration of pipeline-riser with the inclination of the downcomer varied from-2°to-5°to investigated the effect of the elbow on the frictional pressure drop in the riser. The inlet gas velocity ranges from 0.03 to 6.2 m/s, and liquid velocity varies from 0.02 to 1.3 m/s. A total of885 experimental data points including 782 on air-water flows and 103 on air-oil flows are obtained and used to access the prediction ability of the correlations. Comparison of the predicted results with the measured data indicate that a majority of the investigated correlations under-predict the pressure drop on severe slugging. The result of this study highlights the requirement of new method considering the effect of pipe layout on the frictional pressure drop. 展开更多
关键词 Frictional pressure drop Pipeline-riser Gas-liquid two-phase flow Severe slugging correlATION
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Variational data encoding and correlations in quantum-enhanced machine learning
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作者 Ming-Hao Wang Hua L¨u 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期298-306,共9页
Leveraging the extraordinary phenomena of quantum superposition and quantum correlation,quantum computing offers unprecedented potential for addressing challenges beyond the reach of classical computers.This paper tac... Leveraging the extraordinary phenomena of quantum superposition and quantum correlation,quantum computing offers unprecedented potential for addressing challenges beyond the reach of classical computers.This paper tackles two pivotal challenges in the realm of quantum computing:firstly,the development of an effective encoding protocol for translating classical data into quantum states,a critical step for any quantum computation.Different encoding strategies can significantly influence quantum computer performance.Secondly,we address the need to counteract the inevitable noise that can hinder quantum acceleration.Our primary contribution is the introduction of a novel variational data encoding method,grounded in quantum regression algorithm models.By adapting the learning concept from machine learning,we render data encoding a learnable process.This allowed us to study the role of quantum correlation in data encoding.Through numerical simulations of various regression tasks,we demonstrate the efficacy of our variational data encoding,particularly post-learning from instructional data.Moreover,we delve into the role of quantum correlation in enhancing task performance,especially in noisy environments.Our findings underscore the critical role of quantum correlation in not only bolstering performance but also in mitigating noise interference,thus advancing the frontier of quantum computing. 展开更多
关键词 quantum machine learning variational data encoding quantum correlation
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Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis
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作者 Y.Lahlou B.Maroufi M.Daoud 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期204-211,共8页
Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum computation.Essentially,for quantum systems prepared in pure states,it is difficult to... Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum computation.Essentially,for quantum systems prepared in pure states,it is difficult to differentiate between quantum entanglement and quantum correlation.Nonetheless,this indistinguishability is no longer holds for mixed states.To contribute to a better understanding of this differentiation,we have explored a simple model for both generating and measuring these quantum correlations.Our study concerns two macroscopic mechanical resonators placed in separate Fabry–Pérot cavities,coupled through the photon hopping process.this system offers a comprehensively way to investigate and quantify quantum correlations beyond entanglement between these mechanical modes.The key ingredient in analyzing quantum correlation in this system is the global covariance matrix.It forms the basis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,respectively.Our study reveals that the Gaussian interferometric power(P_(G)^(m))proves to be a more suitable metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping. 展开更多
关键词 quantum correlations ENTANGLEMENT Gaussian interferometric power logarithmic negativity optomechanics photon hopping
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Modelling of pressure-strain correlations for Taylor-Proudman turbulence 被引量:1
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作者 符松 《Science China Mathematics》 SCIE 1998年第6期638-646,共9页
The theoretical foundation for the modelling of the turbulent pressure\|strain correlations in rotating reference frame is presented. Based on the recently developed materially\|frame indifference principle it is obse... The theoretical foundation for the modelling of the turbulent pressure\|strain correlations in rotating reference frame is presented. Based on the recently developed materially\|frame indifference principle it is observed that most of the existing second\|moment closures violate the Taylor\|Proudman theorem in the limit of rapid rotation. It is shown that the application of the materially\|frame indifference principle gives rise to the formation of a new pressure\|strain correlation model which satisfies the Taylor\|Proudman theorem. 展开更多
关键词 second\|moment CLOSURE rotating flows pressure\|strain correlations non\|inertial frame Taylor\|Proud man theorem.
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Spatial correlations in time and frequency domains between chlorophyll-a concentration and environmental factors in the Bohai Sea
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作者 Wan XU Di MU +1 位作者 Zhenteng YANG Dekui YUAN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1143-1156,共14页
Based on the reconstructed MODIS data and ECMWF reanalysis data from 2003 to 2021,spatial correlations between chlorophyll a(Chl a)and sea surface temperature(SST),photosynthetically available radiation(PAR),aerosol o... Based on the reconstructed MODIS data and ECMWF reanalysis data from 2003 to 2021,spatial correlations between chlorophyll a(Chl a)and sea surface temperature(SST),photosynthetically available radiation(PAR),aerosol optical thickness(AOT),and wind speed(WS)in the Bohai Sea were analyzed from the perspective of time domain and frequency domain.Results indicate that the frequency domain analysis was more conducive to revealing the correlations between Chl a and environmental factors.The spatial pattern of time-domain correlations was similar to the isobaths of the Bohai Sea,which was positive in shallow waters and negative in deep waters for SST,PAR,and AOT,and was reversed for WS.Frequency-domain correlations were obtained by performing Fourier Transform and were higher than correlations in time domain.The spatial distributions indicated that the effects of SST and PAR on Chl a were greater than AOT and WS in the Bohai Sea.Additionally,cross-spectrum analysis was applied to explore the response relationships.A depth-dependent pattern was shown in correlations and time lags,indicating that the influential mechanism of environmental factors on Chl-a concentration is related to seawater depth. 展开更多
关键词 chlorophyll a(Chl a) frequency domain spatial correlation Bohai Sea
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Spatial correlations in ground motion intensity measuring from the 2023 Türkiye earthquake
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作者 Guoliang Shao Ruizhi Wen +2 位作者 Hongwei Wang Yeifei Ren Baofeng Zhou 《Earthquake Research Advances》 CSCD 2024年第1期14-22,共9页
When evaluating an area's seismic risk or resilience,it is necessary to use the spatial correlation to analyze the ground motion parameters of multiple sites together in an earthquake.These two large earthquakes i... When evaluating an area's seismic risk or resilience,it is necessary to use the spatial correlation to analyze the ground motion parameters of multiple sites together in an earthquake.These two large earthquakes in Türkiye provided the possibility for spatial correlation analysis of ground motion intensity measurements in this area.Based on the strong motion records provided by The Disaster and Emergency Management Authority of Türkiye(AFAD),this study uses the local ground motion prediction equation in Türkiye to give spatial correlation analysis of Intensity Measurements.This study gives an exponential model based on a semivariogram and compares it with the correlation model obtained from previous studies. 展开更多
关键词 Spatial correlation Semi-variance Türkiye GMPE
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Classical Correlations vs Quantum Correlations—Similarities, Differences, Opportunities
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作者 Gunter Meissner Sidy Danioko Pedro Villarreal 《Journal of Applied Mathematics and Physics》 2024年第9期3237-3260,共24页
Classical Correlations were founded in 1900 by Karl Pearson and have since been applied as a statistical tool in virtually all sciences. Quantum correlations go back to Albert Einstein et al. in 1935 and Erwin Schr... Classical Correlations were founded in 1900 by Karl Pearson and have since been applied as a statistical tool in virtually all sciences. Quantum correlations go back to Albert Einstein et al. in 1935 and Erwin Schrödinger’s responses shortly after. In this paper, we contrast classical with quantum correlations. We find that classical correlations are weaker than quantum correlations in the CHSH framework. With respect to correlation matrices, the trace of classical correlation matrices is dissimilar to quantum density matrices. However, the off-diagonal terms have equivalent interpretations. We contrast classical dynamic (i.e., time evolving) stochastic correlation with dynamic quantum density matrices and find that the off-diagonal elements, while different in nature, have similar interpretations. So far, due to the laws of quantum physics, no classical correlations are applied to the quantum spectrum. However, conversely, quantum correlations are applied in classical environments such as quantum computing, cryptography, metrology, teleportation, medical imaging, laser technology, the quantum Internet and more. 展开更多
关键词 Classical correlations Quantum correlations CHSH Framework correlation Matrices Quantum Computing
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Repeat Sequences and Base Correlations in Human Y Chromosome Palindromes 被引量:1
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作者 金能智 刘子贤 +1 位作者 齐燕姣 邱文元 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第3期255-261,339,共8页
On the basis of information theory and statistical methods, we use mutual information, n- tuple entropy and conditional entropy, combined with biological characteristics, to analyze the long range correlation and shor... On the basis of information theory and statistical methods, we use mutual information, n- tuple entropy and conditional entropy, combined with biological characteristics, to analyze the long range correlation and short range correlation in human Y chromosome palindromes. The magnitude distribution of the long range correlation which can be reflected by the mutual information is PS〉PSa〉PSb (P5a and P5b are the sequences that replace solely Alu repeats and all interspersed repeats with random uneorrelated sequences in human Y chromosome palindrome 5, respectively); and the magnitude distribution of the short range correlation which can be reflected by the n-tuple entropy and the conditional entropy is PS〉P5a〉PSb〉random uncorrelated sequence. In other words, when the Alu repeats and all interspersed repeats replace with random uneorrelated sequence, the long range and short range correlation decrease gradually. However, the random nncorrelated sequence has no correlation. This research indicates that more repeat sequences result in stronger correlation between bases in human Y chromosome. The analyses may be helpful to understand the special structures of human Y chromosome palindromes profoundly. 展开更多
关键词 Human Y chromosome PALINDROME Mutual information Long range correlation Short range correlation
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Estimates of Heritability and Genetic Correlations for Growth Traits in Chinese Shrimp Fenneropenaeus chinensis 被引量:2
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作者 何玉英 王清印 +3 位作者 谭乐义 李健 陈华增 李吉涛 《Agricultural Science & Technology》 CAS 2011年第4期613-616,共4页
[Objective] The aim was to estimate the heritability and genetic correlations of growth traits of Chinese shrimp Fenneropenaeus chinensis so as to provide basis and technical parameters for the breeding and selecting ... [Objective] The aim was to estimate the heritability and genetic correlations of growth traits of Chinese shrimp Fenneropenaeus chinensis so as to provide basis and technical parameters for the breeding and selecting of Chinese shrimp.[Method] 51 full-sib families(including 35 half-sib families)of the Chinese shrimp F.chinensis were obtained by artificial insemination.Four growth traits of these families were measured,including body length,cephalothorax length,abdorminal segment length and body weight.According to quantitative genetics theory,the heritability of each growth trait,genetic and phenotypic correlation among these traits was statistically studied.[Result] The heritability was 0.36-0.51 for body length,0.14-0.24 for cephalothorax length,0.25-0.50 for abdominal segment length,and 0.04-0.29 for body weight.High and positive genetic correlations were obtained among growth traits.The genetic correlation between body weight and abdominal segment length was the highest(0.92),followed by body length and abdominal segment length(0.91),body length and body weight(0.88),body weight and cephalothorax length(0.87),abdominal segment length and cephalothorax length(0.86),while the genetic correlation between body length and cephalothorax length was the lowest(0.83).[Conclusion] The phenotypic correlation of body length,cephalothorax length,abdorminal segment length and body weight of Chinese shrimp F.chinensis were from 0.80 to 0.90 with extremely significant difference(P0.01)among the four growth traits by t-test. 展开更多
关键词 Fenneropenaeus chinensis Growth traits HERITABILITY Genetic correlation
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Vector Correlations and Product Rotational Alignments of Reactions Ca+RBr→CaBr+R(R=CH_(3),C_(2) H_(5) and n-C_(3) H_(7)) 被引量:1
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作者 马建军 丛书林 +1 位作者 张志红 王艳秋 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期117-122,共6页
The quasiclassical trajectory method is used to study the vector correlations of the reactions Ca+RBr (R=CH3, C2H5 and n-C3H7Br) and the rotational alignment of product CaBr. The product rotational alignment parame... The quasiclassical trajectory method is used to study the vector correlations of the reactions Ca+RBr (R=CH3, C2H5 and n-C3H7Br) and the rotational alignment of product CaBr. The product rotational alignment parameters at different collision energies and the vector correlations between the reagent and product are numerically calculated. The vector correlations are described by using the angle distribution functions P(θr), P(φr), P(θr, φr) and the polarization-dependent differential cross sections (PDDCSs). The peak values of P(θr) of the product CaBr from Ca+CH3Br are larger than those from Ca+C2H5Br and Ca+n-C3H7Br. The peak of P(θr) at φr= 3π/2 is apparently stronger than that at φr= x/2 for the three reactions Ca+RBr. The calculation results show that the rotational angular momentum of the product CaBr is not only aligned, but also oriented along the direction which is perpendicular to the scattering plane.The product CaBr molecules are strongly scattered forward. The orientation and alignment of the product angular momentum will affect the scattering direction of the product molecules to varying degrees. 展开更多
关键词 Quasiclassical trajectory Vector correlation Orientation and alignment
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Correlations between Quality Index and Content of Cellulose and Lignin in Upper Leaves of Fluecured Tobacco in Wulin Mountain Area
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作者 刘晓冰 孟霖 +4 位作者 梁盟 王程栋 宋文静 郑家宝 徐宜民 《Agricultural Science & Technology》 CAS 2015年第10期2135-2140,2143,共7页
In order to study the correlations among quality indexes of tobacco leaf and contents of cellulose and lignin in upper leaves of flue-cured tobacco, 48 B2F flue-cured tobacco samples in seven counties of Wulin mountai... In order to study the correlations among quality indexes of tobacco leaf and contents of cellulose and lignin in upper leaves of flue-cured tobacco, 48 B2F flue-cured tobacco samples in seven counties of Wulin mountain area in 2011 and 2012 were used as test materials to measure the contents of cellulose and lignin in tobacco leaves and analyze the differences among varieties and between years. Meanwhile, correlations among contents of cellulose and lignin and appearance quality, physical characteristics, general chemical components and indexes of senso- ry quality were studied. The results showed that the contents of cellulose and lignin had no significant difference among years and varieties. Cellulose content was sig- nificantly correlated with some indexes of appearance qualities, physical indexes, general chemical compositions and sensory qualities. Lignin content was significantly correlated with grayness and oil content but not other quality indexes of tobacco leaf. It could be seen that the differences of cellulose and lignin contents between different years and among varieties were not significant. Cellulose content was closely correlated with quality indexes of tobacco leaf while lignin content had a small effect on tobacco leaf quality. 展开更多
关键词 Flue-cured tobacco Upper leaf CELLULOSE LIGNIN correlation analysis
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Evaluation of selenium and carotenoid concentrations of 200 foxtail millet accessions from China and their correlations with agronomic performance 被引量:16
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作者 LIU Min-xuan ZHANG Zong-wen +3 位作者 REN Gui-xing ZHANG Qi WANG Yin-yue LU Ping 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第7期1449-1457,共9页
As selenium and carotenoids are essential micronutrients, the determination of their concentrations in different varieties is important in the breeding of foxtail milet (Setaria italicaL. P.Beauv.). To identify sele... As selenium and carotenoids are essential micronutrients, the determination of their concentrations in different varieties is important in the breeding of foxtail milet (Setaria italicaL. P.Beauv.). To identify selenium- and carotenoid-enriched foxtail milet varieties and to analyze correlations between trace elements and agronomic traits, we measured the selenium and carotenoid concentrations of 200 Chinese accessions by high-performance liquid chromatography and atomic lfuorescence spectrometry. Our analysis revealed that lutein concentration in 200 foxtail milet accessions folowed normal distribution and average was 3.1 μg g–1. The mean value of zeaxanthin concentration in 200 accessions was 8.6 μg g–1. Lutein and zeaxanthin concentrations were higher in the foxtail milet from Liaoning than in varieties from other locations, with averages of 10.0 and 3.5 μg g–1, respectively. The average measured selenium concentration was 100.3 μg kg–1. The highest average selenium concentration, 110.3 μg kg–1, was found in varieties from Shanxi. Varieties from Inner Mongolia had the lowest average selenium concentration, 84.7 μg kg–1, which was signiifcantly lower (P〈0.05) than that of Shanxi. Selenium con-centrations of 23 varieties were higher than 117.9 μg kg–1, accounting for 11.5% of the total, thereby were considered to be enriched in selenium. In addition, we identiifed 29 lutein-enriched varieties (〉4.27 μg g–1) and 30 zeaxanthin-enriched ones (〉12.63 μg g–1), which corresponded to 14.5 and 15% of tested accessions, respectively. Correlation analysis revealed that selenium concentration was signiifcantly positively correlated with spikelet length (P〈0.01), while zeaxanthin concentration was signiifcantly correlated with grass weight (P〈0.05) and spikelet length (P〈0.01). No correlation was found between lutein concentration and agronomic characters, selenium content or zeaxanthin content. Our results should contribute substantialy to the selection of suitable varieties for the development of plants with desired levels of these nutritionaly important elements. These results wil signiifcantly contribute towards selection of the most suitable varieties for obtaining plants with desired levels of these nutritionaly important elements. 展开更多
关键词 foxtail milet varieties SELENIUM carotenoids HPLC correlation analysis
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Variance components and correlations of female fertility traits in Chinese Holstein population 被引量:8
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作者 Aoxing Liu Mogens Sandø Lund +4 位作者 Yachun Wang Gang Guo Ganghui Dong Per Madsen Guosheng Su 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第4期833-841,共9页
Background: The objective of the present study was to estimate(co)variance components of female fertility traits in Chinese Holsteins, considering fertility traits in different parities as different traits. Data on 88... Background: The objective of the present study was to estimate(co)variance components of female fertility traits in Chinese Holsteins, considering fertility traits in different parities as different traits. Data on 88,647 females with 215,632 records(parities) were collected during 2000 to 2014 from 32 herds in the Sanyuan Lvhe Dairy Cattle Center, Beijing, China. The analyzed female fertility traits included interval from calving to first insemination, interval from first to last insemination, days open, conception rate at first insemination, number of inseminations per conception and non-return rates within 56 days after first insemination.Results: The descriptive statistics showed that the average fertility of heifers was superior to that of cows. Moreover,the genetic correlations between the performances of a trait in heifers and in cows were all moderate to high but far from one, which suggested that the performances of a trait in heifers and cows should be considered as different but genetically correlated traits in genetic evaluations. On the other hand, genetic correlations between performances of a trait in different parities of cows were greater than 0.87, with only a few exceptions, but variances were not homogeneous across parities for some traits. The estimated heritabilities of female fertility traits were low; all were below 0.049(except for interval from calving to first insemination). Additionally, the heritabilities of the heifer interval traits were lower than those of the corresponding cow interval traits. Moreover, the heritabilities of the interval traits were higher than those of the threshold traits when measuring similar fertility functions. In general, estimated genetic correlations between traits were highly consistent with the biological categories of the female fertility traits.Conclusions: Interval from calving to first insemination, interval from first to last insemination and non-return rates within 56 days after first insemination are recommended to be included in the selection index of the Chinese Holstein population. The parameters estimated in the present study will facilitate the development of a genetic evaluation system for female fertility traits to improve the reproduction efficiency of Chinese Holsteins. 展开更多
关键词 Chinese HOLSTEINS FEMALE FERTILITY Genetic correlation HERITABILITY
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Charm hadron azimuthal angular correlations in Au+Au collisions at ■=200 GeV from parton scatterings 被引量:7
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作者 Hai Wang Jin-Hui Chen +1 位作者 Yu-Gang Ma Song Zhang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第12期111-118,共8页
The dynamic evolution of the charm hadron in hot quark matter was studied in the framework of a multiphase transport(AMPT)model.We first reproduced the open charm hadron D0pT spectrum in Au+Au collisions at √sNN=200 ... The dynamic evolution of the charm hadron in hot quark matter was studied in the framework of a multiphase transport(AMPT)model.We first reproduced the open charm hadron D0pT spectrum in Au+Au collisions at √sNN=200 GeV by triggering the c c production in AMPT,and then the elliptic flow of charm hadrons was described with different parton cascade cross sections.Charm hadron azimuthal angular correlations were proposed,and they are affected by the different parton crosssection parameter applied in the model,which can facilitate our understanding of the loss of collision energy of charm quarks in hot quark medium and can stimulate further experimental studies. 展开更多
关键词 QUARK GLUON plasma Heavy FLAVOR Twoparticle correlations
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Age–age correlations and early selection for growth traits in 40 half-sib families of Larix principis-rupprechtii 被引量:8
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作者 Mingliang Dong Yingming Fan +2 位作者 Zhihui Wu Futang Lv Jinfeng Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期2111-2117,共7页
Larix principis-rupprechtii Mayr is a dominant species in coniferous forests of North China.However,early selection of L.principis-rupprechtii for growth traits is poorly characterised.To explore the optimal selection... Larix principis-rupprechtii Mayr is a dominant species in coniferous forests of North China.However,early selection of L.principis-rupprechtii for growth traits is poorly characterised.To explore the optimal selection age for this species,heights(HT)and diameters at breast(DBH)of 40 half-sib families were measured at ages 3,12,22,and 28 years in a progeny test population established in the town of Kangjiahui,Shanxi Province.Age trends in heritability,age–age genetic correlations,and early selection efficiency for height and DBH were analysed.The individual heritability of these growth traits varied over time,and maximized at different ages(0.55 at age 12 for HT and 0.48 at age 28 for DBH).The age–age genetic correlations were always positive,and the majority were high(0.790–0.953)between the juvenile and mature ages for HT and DBH.For the same pairs of measurements,HT demonstrated higher age–age genetic correlations than DBH,and both age–age genetic correlation data sets were described well by the linear relationship with the logarithm of the age ratio(r2[0.90).The regression slope for DBH was lower than that for HT.Based on the early selection efficiency estimates,the optimal selection age could be as early as age 6 for DBH and 8–9 years for HT.The results of this study provide information that can be used to assist early selection practices in L.principis-rupprechtii improvement programs in Shanxi Province. 展开更多
关键词 Age–age correlations Early SELECTION HERITABILITY LARIX principis-rupprechtii SELECTION efficiency
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Antioxidations and Their Correlations with Total Flavones and Anthocyanin Contents in Different Black Rice Varieties 被引量:9
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作者 ZHANG Ming-wei GUO Bao-jiang +4 位作者 CHI Jian-wei WEI Zhen-cheng XU Zhi-hong ZHANG Yan ZHANG Rui-fen 《Agricultural Sciences in China》 CAS CSCD 2005年第11期811-819,共9页
The antioxidations and their correlations with total flavones and anthocyanin contents in different black rice varieties were studied. The results indicated that the great differences in total antioxidant capacity (... The antioxidations and their correlations with total flavones and anthocyanin contents in different black rice varieties were studied. The results indicated that the great differences in total antioxidant capacity (TAC), scavenging free radical capacity (SFRC), total flavones and anthocyanin contents existed among 242 black rice varieties. Comparisons of TAC, SFRC, total flavones and anthocyanin contents of different black rice types showed that the differences between black rice and white rice, indica one and japonica one, and nonglutinous one and glutinous one were significant at 0.01 levels, respectively. This showed that the TAC, SFRC, total flavones and anthocyanin contents of japonica type were higher than those of indica one, and nonglutinous type were higher than glutinous one. According to the fast clustering procedure, 242 black rice varieties could be clustered into 10 clusters, 184 indica rice varieties into 10 clusters, and 58 japonica rice varieties into 6 clusters. Most significant (P〈0.01) correlations existed between TAC and total flavones and anthocyanin contents, and between SFRC and total flavones and anthocyanin contents of black rice, respectively. This showed that the antioxidation of black rice was closely correlated with its active compositions of flavones and anthocyanin. 展开更多
关键词 Black rice ANTIOXIDATION Total flavones content Anthocyanin content correlATION
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Study of the correlations between main shocks and aftershocks and aftershock synthesis method 被引量:5
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作者 Zhang Yingnan Zhi Xudong Fan Feng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第4期759-775,共17页
To consider the infl uence of aftershocks in engineering design, the correlations between main shocks and aftershocks should be examined, and an aftershock simulation method with main shock ground motions needs to be ... To consider the infl uence of aftershocks in engineering design, the correlations between main shocks and aftershocks should be examined, and an aftershock simulation method with main shock ground motions needs to be developed. In this study, the data on the sequences of main shock–aftershock ground motions and other related parameters were collected. Using these data, correlations between the magnitude, frequency, duration and energy of the main shock–aftershock ground motions were investigated. The results showed that the magnitude of the aftershock can be larger than that of the main shock. The shapes of the Fourier amplitude spectra of main shocks and aftershocks were similar;however, the predominant frequency and high-frequency components of the aftershock tended to be larger. Considering the magnitude diff erence between the main shock and the aftershock, the correlation of durations was explored. Additionally, a new concept, the duration ratio, was defi ned to describe the concentration of seismic energy release, and main shock energy was strongly positively correlated with the energy attenuated during the main shock–aftershock sequence. Finally, based on these results regarding correlation, an aftershock synthesis using recorded main shock ground motions was constructed with the trigonometric series method for seismic design, and some examples are given to analyze the rationality of this synthetic method. 展开更多
关键词 MAIN shock-aftershock SEQUENCE correlATION AFTERSHOCK synthesis SEISMIC design
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Time series analysis of mantle cycles Part Ⅰ:Periodicities and correlations among seven global isotopic databases 被引量:4
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作者 Stephen J. Puetz Kent C. Condie 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1305-1326,共22页
In this study,seven isotopic databases are presented and analyzed to identify mantle and crustal episodes on a global scale by focusing on periodicity ranging from 70 to 200 million years(Myr).The databases are the la... In this study,seven isotopic databases are presented and analyzed to identify mantle and crustal episodes on a global scale by focusing on periodicity ranging from 70 to 200 million years(Myr).The databases are the largest,or among the largest,compiled for each type of data-with an objective of finding some samples from every region of every continent,to make each database as global as conceivably possible.The databases contain zircon Lu/Hf isotopic data,whole-rock Sm/Nd isotopic data,U/Pb detrital zircon ages,U/Pb igneous zircon ages,U/Pb non-zircon ages,whole-rock Re/Os isotopic data,and large igneous province ages.Part I of this study focuses on the periodicities of age histograms and geochemical averages developed from the seven databases,via spectral and cross-correlation analyses.Natural physical cycles often propagate in exact integer multiples of a fundamental cycle,referred to as harmonics.The tests show that harmonic geological cycles of^93.5 and^187 Myr have persisted throughout terrestrial history,and the cyclicities are statistically significant for U/Pb igneous zircon ages,U/Pb detrital zircon ages,U/Pb zircon-rim ages,large igneous province ages,meanεHf(t)for all samples,meanεHf(t)values for igneous-only samples,and relative abundance of mafic rocks.Equally important,cross-correlation analyses show these seven time-series are nearly synchronous(±7 Myr)with a model consisting of periodicities of 93.5 and 187 Myr.Additionally,the similarities between peaks in the 93.5 and 187 Myr mantle cycles and terminal ages of established and suspected superchrons provide a framework for predicting and testing superchron periodicity. 展开更多
关键词 ZIRCON Database Isotope Statistical ANALYSIS Spectral ANALYSIS Cross correlation
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