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Study of hybrid nanofluid flow in a stationary cone-disk system with temperature-dependent fluid properties
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作者 A.S.JOHN B.MAHANTHESH G.LORENZINI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第4期677-694,共18页
Cone-disk systems find frequent use such as conical diffusers,medical devices,various rheometric,and viscosimetry applications.In this study,we investigate the three-dimensional flow of a water-based Ag-Mg O hybrid na... Cone-disk systems find frequent use such as conical diffusers,medical devices,various rheometric,and viscosimetry applications.In this study,we investigate the three-dimensional flow of a water-based Ag-Mg O hybrid nanofluid in a static cone-disk system while considering temperature-dependent fluid properties.How the variable fluid properties affect the dynamics and heat transfer features is studied by Reynolds's linearized model for variable viscosity and Chiam's model for variable thermal conductivity.The single-phase nanofluid model is utilized to describe convective heat transfer in hybrid nanofluids,incorporating the experimental data.This model is developed as a coupled system of convective-diffusion equations,encompassing the conservation of momentum and the conservation of thermal energy,in conjunction with an incompressibility condition.A self-similar model is developed by the Lie-group scaling transformations,and the subsequent self-similar equations are then solved numerically.The influence of variable fluid parameters on both swirling and non-swirling flow cases is analyzed.Additionally,the Nusselt number for the disk surface is calculated.It is found that an increase in the temperature-dependent viscosity parameter enhances heat transfer characteristics in the static cone-disk system,while the thermal conductivity parameter has the opposite effect. 展开更多
关键词 hybrid nanofluid cone-disk system laminar flow variable fluid property Nusselt number
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Systematic Method for Constructing Lewis Representations
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作者 Lahbib Abbas Lahcen Bih +3 位作者 Khalid Yamni Abderrahim Elyahyaouy Abdelmalik El Attaoui Zahra Ramzi 《Open Journal of Inorganic Chemistry》 2024年第1期1-18,共18页
The systematic method for constructing Lewis representations is a method for representing chemical bonds between atoms in a molecule. It uses symbols to represent the valence electrons of the atoms involved in the bon... The systematic method for constructing Lewis representations is a method for representing chemical bonds between atoms in a molecule. It uses symbols to represent the valence electrons of the atoms involved in the bond. Using a number of rules in a defined order, it is often better suited to complicated cases than the Lewis representation of atoms. This method allows us to determine the formal charge and oxidation number of each atom in the edifice more efficiently than other methods. 展开更多
关键词 systematic Method Lewis Representation Chemical Bond Formal Charge Oxidation Number
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Modeling Expected Failure Considering Repair Time and Degradation: A Rail System Case Study
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作者 Maryam Hamidi Atefe Sedaghat +1 位作者 Amir Gharehgozli Ferenc Szidarovszky 《Journal of Transportation Technologies》 2024年第2期236-254,共19页
The repeated failures of any equipment or systems are modeled as a renewal process. The management needs an assessment of the number of future failures to allocate the resources needed for fast repairs. Based on the i... The repeated failures of any equipment or systems are modeled as a renewal process. The management needs an assessment of the number of future failures to allocate the resources needed for fast repairs. Based on the idea of expectation by conditioning, special Volterra-type integral equations are derived for general types of repairs, considering the length of repair and reduced degradation of the idle object. In addition to minimal repair and failure replacement, partial repairs are also discussed when the repair results in reduction of the number of future failures or decreases the effective age of the object. Numerical integration-based algorithm and simulation study are performed to solve the resulting integral equation. Since the geometry degradation in different dimensions of a rail track and controlling and maintaining defects are of importance, a numerical example using the rail industry data is conducted. Expected number of failures of different failure type modes in rail track is calculated within a two-year interval. Results show that within a two-year period, anticipated occurrences of cross level failures, surface failures, and DPI failures are 2.4, 3.8, and 5.8, respectively. 展开更多
关键词 Renewal Theory Expected Number of Failures Partial Repair Minimal Repair
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SOME RESULTS ON BUNDLE SYSTEMS FOR A COUNTABLE DISCRETE AMENABLE GROUP ACTION
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作者 潘娟 周云华 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1382-1402,共21页
We consider the style number, independence number and entropy for a frame bundle dynamical system. The base system of which is a countable discrete amenable group action on a compact metric space. We obtain the existe... We consider the style number, independence number and entropy for a frame bundle dynamical system. The base system of which is a countable discrete amenable group action on a compact metric space. We obtain the existence of cover measures, an ergodic theorem about mean linear independence and the style number, and a variational principle for style numbers and independence numbers. We also study the relationship between the entropy of base systems and that of their bundle systems. 展开更多
关键词 mean linear independence style number independence number ENTROPY
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感知学生情绪的Java程序设计课堂教学改革
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作者 李向 王毅 +1 位作者 陈宇 姚文鑫 《计算机教育》 2024年第2期90-94,共5页
针对课堂中学生注意力与情绪状态存在特定关联,提出感知学生情绪的课堂教学改革思路,以Java程序设计课程中“循环语法结构的运用”课堂教学实践为例,阐述如何将经典水仙花数问题分解并运用穷举思想、组合思想和归纳思想求解,借此引出扩... 针对课堂中学生注意力与情绪状态存在特定关联,提出感知学生情绪的课堂教学改革思路,以Java程序设计课程中“循环语法结构的运用”课堂教学实践为例,阐述如何将经典水仙花数问题分解并运用穷举思想、组合思想和归纳思想求解,借此引出扩展问题,最终实现增强学生学习自信心、培养算法思维能力的课堂教学改革目的。 展开更多
关键词 情绪感知 课堂教学 JAVA程序设计 Narcissistic Numbers
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A Study on the Transmission Dynamics of the Omicron Variant of COVID-19 Using Nonlinear Mathematical Models 被引量:1
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作者 S.Dickson S.Padmasekaran +2 位作者 Pushpendra Kumar Kottakkaran Sooppy Nisar Hamidreza Marasi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2265-2287,共23页
This research examines the transmission dynamics of the Omicron variant of COVID-19 using SEIQIcRVW and SQIRV models,considering the delay in converting susceptible individuals into infected ones.The significant delay... This research examines the transmission dynamics of the Omicron variant of COVID-19 using SEIQIcRVW and SQIRV models,considering the delay in converting susceptible individuals into infected ones.The significant delays eventually resulted in the pandemic’s containment.To ensure the safety of the host population,this concept integrates quarantine and the COVID-19 vaccine.We investigate the stability of the proposed models.The fundamental reproduction number influences stability conditions.According to our findings,asymptomatic cases considerably impact the prevalence of Omicron infection in the community.The real data of the Omicron variant from Chennai,Tamil Nadu,India,is used to validate the outputs. 展开更多
关键词 Omicron local stability reproduction number steady states global stability
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一种新的Sparse Numbering Schema及其存储方法研究 被引量:1
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作者 郭松涛 朱征宇 《计算机工程与应用》 CSCD 北大核心 2004年第27期176-178,187,共4页
由于采用传统的NumberingSchema方法来表示XML文件结构不便于元素更新,论文在改进的基础上提出了SparseNumberingSchema。利用SparseNumberingSchema,在插入新的结点时,不需要重新计算其它结点的start和end值。鉴于目前关于NumberingSch... 由于采用传统的NumberingSchema方法来表示XML文件结构不便于元素更新,论文在改进的基础上提出了SparseNumberingSchema。利用SparseNumberingSchema,在插入新的结点时,不需要重新计算其它结点的start和end值。鉴于目前关于NumberingSchema存储方法的研究较为少见,论文给出了SparseNumberingSchema在关系数据库中的存储方法。该存储方法不仅有利于根据start值快速建立索引,而且可以节省存储空间。 展开更多
关键词 numbering SCHEMA 存储 XML
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Effects of multiple shapes for steady flow with transformer oil+Fe_(3)O_(4)+TiO_(2) between two stretchable rotating disks
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作者 M.RAHMAN M.TURKYILMAZOGLU Z.MUSHTAQ 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第2期373-388,共16页
In this study,we examine the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating disks.The steady flow of hybrid nanofluids with transformer oil as the bas... In this study,we examine the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating disks.The steady flow of hybrid nanofluids with transformer oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is considered.Several shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are studied.Every shape exists in the same volume of a nanoparticle.The leading equations(partial differential equations(PDEs))are transformed to the nonlinear ordinary differential equations(ODEs)with the help of similarity transformations.The system of equations takes the form of ODEs depending on the boundary conditions,whose solutions are computed numerically by the bvp4c MATLAB solver.The outputs are compared with the previous findings,and an intriguing pattern is discovered,such that the tangential velocity is increased for the rotation parameter,while it is decreased by the stretching values because of the lower disk.For the reaction rate parameter,the concentration boundary layer becomes shorter,and the activation energy component increases the rate at which mass transfers come to the higher disk but have the opposite effect on the bottom disk.The ranges of various parameters taken into account are Pr=6.2,Re=2,M=1.0,φ_(1)=φ_(2)=0.03,K=0.5,S=-0.1,Br=0.3,Sc=2.0,α_(1)=0.2,γ=0.1,E_(n)=2.0,and q=1.0,and the rotation factor K is within the range of 0 to 1. 展开更多
关键词 transformer oil Brinkman number skin friction coefficient double rotating disk Nusselt number Sherwood number
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Quantum geometric tensor and the topological characterization of the extended Su-Schrieffer-Heeger model
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作者 曾相龙 赖文喜 +1 位作者 魏祎雯 马余全 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期260-265,共6页
We investigate the quantum metric and topological Euler number in a cyclically modulated Su-Schrieffer-Heeger(SSH)model with long-range hopping terms.By computing the quantum geometry tensor,we derive exact expression... We investigate the quantum metric and topological Euler number in a cyclically modulated Su-Schrieffer-Heeger(SSH)model with long-range hopping terms.By computing the quantum geometry tensor,we derive exact expressions for the quantum metric and Berry curvature of the energy band electrons,and we obtain the phase diagram of the model marked by the first Chern number.Furthermore,we also obtain the topological Euler number of the energy band based on the Gauss-Bonnet theorem on the topological characterization of the closed Bloch states manifold in the first Brillouin zone.However,some regions where the Berry curvature is identically zero in the first Brillouin zone result in the degeneracy of the quantum metric,which leads to ill-defined non-integer topological Euler numbers.Nevertheless,the non-integer"Euler number"provides valuable insights and an upper bound for the absolute values of the Chern numbers. 展开更多
关键词 quantum geometric tensor topological Euler number Chern number Berry curvature quantum metric Su-Schrieffer-Heeger(SSH)model
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A novel Effective Panicle Number per Plant 4 haplotype enhances grain yield by coordinating panicle number and grain number in rice
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作者 Yun Wang Xiaoqian Wang +6 位作者 Laiyuan Zhai Sundus Zafar Congcong Shen Shuangbing Zhu Kai Chen Yun Wang Jianlong Xu 《The Crop Journal》 SCIE CSCD 2024年第1期202-212,共11页
Increasing effective panicle number per plant(EPN)is one approach to increase yield potential in rice.However,molecular mechanisms underlying EPN remain unclear.In this study,we integrated mapbased cloning and genome-... Increasing effective panicle number per plant(EPN)is one approach to increase yield potential in rice.However,molecular mechanisms underlying EPN remain unclear.In this study,we integrated mapbased cloning and genome-wide association analysis to identify the EPN4 gene,which is allelic to NARROW LEAF1(NAL1).Overexpression lines containing the Teqing allele(TQ)of EPN4 had significantly increased EPN.NIL-EPN4^(TQ) in japonica(geng)cultivar Lemont(LT)exhibited significantly improved EPN but decreased grain number and flag leaf size relative to LT.Haplotype analysis indicated that accessions with EPN4-1 had medium EPN,medium grain number,and medium grain weight,but had the highest grain yield among seven haplotypes,indicating that EPN4-1 is an elite haplotype of EPN4 for positive coordination of the three components of grain yield.Furthermore,accessions carrying the combination of EPN4-1 and haplotype GNP1-6 of GNP1 for grain number per panicle showed higher grain yield than those with other allele combinations.Therefore,pyramiding of EPN4-1 and GNP1-6 could be a preferred approach to obtain high yield potential in breeding. 展开更多
关键词 RICE Effective panicle number per plant Grain number per panicle HAPLOTYPE Grain yield potential
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Genome-wide investigation to assess copy number variants in the Italian local chicken population
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作者 Filippo Cendron Martino Cassandro Mauro Penasa 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期563-577,共15页
Background Copy number variants(CNV)hold significant functional and evolutionary importance.Numerous ongoing CNV studies aim to elucidate the etiology of human diseases and gain insights into the population structure ... Background Copy number variants(CNV)hold significant functional and evolutionary importance.Numerous ongoing CNV studies aim to elucidate the etiology of human diseases and gain insights into the population structure of livestock.High-density chips have enabled the detection of CNV with increased resolution,leading to the identification of even small CNV.This study aimed to identify CNV in local Italian chicken breeds and investigate their distribution across the genome.Results Copy number variants were mainly distributed across the first six chromosomes and primarily associated with loss type CNV.The majority of CNV in the investigated breeds were of types 0 and 1,and the minimum length of CNV was significantly larger than that reported in previous studies.Interestingly,a high proportion of the length of chromosome 16 was covered by copy number variation regions(CNVR),with the major histocompatibility complex being the likely cause.Among the genes identified within CNVR,only those present in at least five animals across breeds(n=95)were discussed to reduce the focus on redundant CNV.Some of these genes have been associated to functional traits in chickens.Notably,several CNVR on different chromosomes harbor genes related to muscle development,tissue-specific biological processes,heat stress resistance,and immune response.Quantitative trait loci(QTL)were also analyzed to investigate potential overlapping with the identified CNVR:54 out of the 95 gene-containing regions overlapped with 428 QTL associated to body weight and size,carcass characteristics,egg production,egg components,fat deposition,and feed intake.Conclusions The genomic phenomena reported in this study that can cause changes in the distribution of CNV within the genome over time and the comparison of these differences in CNVR of the local chicken breeds could help in preserving these genetic resources. 展开更多
关键词 CHICKEN Copy number variant CONSERVATION Local breed SNP
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The wheat sucrose synthase gene TaSus1 is a determinant of grain number per spike
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作者 Liping Shen Lili Zhang +20 位作者 Changbin Yin Xiaowan Xu Yangyang Liu Kuocheng Shen He Wu Zhiwen Sun Ke Wang Zhonghu He Xueyong Zhang Chenyang Hao Jian Hou Aoyue Bi Xuebo Zhao Daxing Xu Botao Ye Xuchang Yu Ziying Wang Danni Liu Yuanfeng Hao Fei Lu Zifeng Guo 《The Crop Journal》 SCIE CSCD 2024年第1期295-300,共6页
Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The e... Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions. 展开更多
关键词 Domestication selection Fertile spikelet number per spike(FSN) Geographical differentiation Grain number per spike(GNS) TaSus1
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Overall Assessment of Heat Transfer for a Rarefied Flow in a Microchannel with Obstacles Using Lattice Boltzmann Method
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作者 Siham Hammid Khatir Naima +7 位作者 Omolayo M.Ikumapayi Cheikh Kezrane Abdelkrim Liazid Jihad Asad Mokdad Hayawi Rahman Farhan Lafta Rashid Naseer Ali Hussien Younes Menni 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期273-299,共27页
The objective of this investigation is to assess the effect of obstacles on numerical heat transfer and fluid flow momentum in a rectangular microchannel(MC).Two distinct configurations were studied:one without obstac... The objective of this investigation is to assess the effect of obstacles on numerical heat transfer and fluid flow momentum in a rectangular microchannel(MC).Two distinct configurations were studied:one without obstacles and the other with alternating obstacles placed on the upper and lower walls.The research utilized the thermal lattice Boltzmann method(LBM),which solves the energy and momentum equations of fluids with the BGK approximation,implemented in a Python coding environment.Temperature jump and slip velocity conditions were utilized in the simulation for the MC and extended to all obstacle boundaries.The study aims to analyze the rarefaction effect,with Knudsen numbers(Kn)of 0.012,0.02,and 0.05.The outcomes indicate that rarefaction has a significant impact on the velocity and temperature distribution.The presence of nine obstacles led to slower fluid movement inside the microchannel MC,resulting in faster cooling at the outlet.In MCs with obstacles,the rarefaction effect plays a crucial role in decreasing the Nusselt number(Nu)and skin friction coefficient(Cf).Furthermore,the study demonstrated that the obstacles played a crucial role in boosting fluid flow and heat transfer in the MC.The findings suggest that the examined configurations could have potential applications as cooling technologies in micro-electro-mechanical systems and microdevice applications. 展开更多
关键词 MICROFLUID rarefied flow LBM MICROCHANNEL Knudsen number numerical simulation
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高马赫数球状气泡动力学理论研究
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作者 韩泠西 颜帅 李帅 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第1期39-48,共10页
The compressibility of fluids has a profound influence on oscillating bubble dynamics,as characterized by the Mach number.However,current theoretical frameworks for bubbles,whether at the first or second order of the ... The compressibility of fluids has a profound influence on oscillating bubble dynamics,as characterized by the Mach number.However,current theoretical frameworks for bubbles,whether at the first or second order of the Mach number,are primarily confined to scenarios characterized by weak compressibility.Thus,a critical need to elucidate the precise range of applicability for both first-and second-order bubble theories arises.Herein,we investigate the suitability and constraints of bubble theories with different orders through a comparative analysis involving experimental data and numerical simulations.The focal point of our investigation encompasses theories such as the Rayleigh–Plesset,Keller,Herring,and second-order bubble equations.Furthermore,the impact of parameters inherent in the second-order equations is examined.For spherical oscillating bubble dynamics in a free field,our findings reveal that the first-and second-order bubble theories are applicable when Ma≤0.3 and 0.4,respectively.For a single sonoluminescence bubble,we define an instantaneous Mach number,Mai.The second-order theory shows abnormal sensibility when Mai is high,which is negligible when Mai≤0.4.The results of this study can serve as a valuable reference for studying compressible bubble dynamics. 展开更多
关键词 Bubble dynamics Spherical bubble CAVITATION COMPRESSIBILITY Mach number
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Impacts of Aggregation Methods and Trophospecies Number on the Structure and Function of Marine Food Webs
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作者 LI Pengcheng ZHANG Chongliang +4 位作者 XU Binduo JI Yupeng LI Fan REN Yiping XUE Ying 《Journal of Ocean University of China》 CAS CSCD 2024年第1期190-198,共9页
Aggregation of species with similar ecological properties is one of the effective methods to simplify food web researches.However,species aggregation will affect not only the complexity of modeling process but also th... Aggregation of species with similar ecological properties is one of the effective methods to simplify food web researches.However,species aggregation will affect not only the complexity of modeling process but also the accuracy of models’outputs.Selection of aggregation methods and the number of trophospecies are the keys to study the simplification of food web.In this study,three aggregation methods,including taxonomic aggregation(TA),structural equivalence aggregation(SEA),and self-organizing maps(SOM),were analyzed and compared with the linear inverse model–Markov Chain Monte Carlo(LIM-MCMC)model.Impacts of aggregation methods and trophospecies number on food webs were evaluated based on the robustness and unitless of ecological net-work indices.Results showed that aggregation method of SEA performed better than the other two methods in estimating food web structure and function indices.The effects of aggregation methods were driven by the differences in species aggregation principles,which will alter food web structure and function through the redistribution of energy flow.According to the results of mean absolute percentage error(MAPE)which can be applied to evaluate the accuracy of the model,we found that MAPE in food web indices will increase with the reducing trophospecies number,and MAPE in food web function indices were smaller and more stable than those in food web structure indices.Therefore,trade-off between simplifying food webs and reflecting the status of ecosystem should be con-sidered in food web studies.These findings highlight the importance of aggregation methods and trophospecies number in the analy-sis of food web simplification.This study provided a framework to explore the extent to which food web models are affected by dif-ferent species aggregation,and will provide scientific basis for the construction of food webs. 展开更多
关键词 LIM-MCMC model species aggregation trophospecies number aggregation methods food web indices
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The first factor affecting dryland winter wheat grain yield under various mulching measures: Spike number
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作者 Yingxia Dou Hubing Zhao +4 位作者 Huimin Yang Tao Wang Guanfei Liu Zhaohui Wang Sukhdev Malhi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期836-848,共13页
Water is the key factor limiting dryland wheat grain yield.Mulching affects crop yield and yield components by affecting soil moisture.Further research is needed to determine the relationships between yield components... Water is the key factor limiting dryland wheat grain yield.Mulching affects crop yield and yield components by affecting soil moisture.Further research is needed to determine the relationships between yield components and soil moisture with yield,and to identify the most important factor affecting grain yield under various mulching measures.A long-term 9-yearifeld experiment in the Loess Plateau of Northwest China was carried out with three treatments:no mulch (CK),plastic mulch (M_(P)) and straw mulch (M_(S)).Yield factors and soil moisture were measured,and the relationships between them were explored by correlation analysis,structural equation modeling and significance analysis.The results showed that compared with CK,the average grain yields of M_(P) and M_(S) increased by 13.0and 10.6%,respectively.The average annual grain yield of the M_(P) treatment was 134 kg ha^(–1) higher than the M_(S) treatment.There were no significant differences in yield components among the three treatments (P<0.05).Soil water storage of the M_(S) treatment was greater than the M_(P) treatment,although the differences were not statistically signifiant.Soil water storage during the summer fallow period (SWSSF) and soil water storage before sowing (SWSS) of M_(S) were significantly higher than in CK,which increased by 38.5 and 13.6%,respectively.The relationship between M_(P) and CK was not statistically significant for SWSSF,but the SWSS in M_(P) was significantly higher than in CK.In terms of soil water storage after harvest (SWSH) and water consumption in the growth period(ET),there were no signi?cant differences among the three treatments.Based on the three analysis methods,we found that spike number and ET were positively correlated with grain yield.However,the relative importance of spike number to yield was the greatest in the M_(P )and M_(S) treatments,while that of ET was the greatest in CK.Suifcient SWSSF could indirectly increase spike number and ET in the three treatments.Based on these results,mulch can improve yield and soil water storage.The most important factor affecting the grain yield of dryland wheat was spike number under mulching,and ET with CK.These findings may help us to understand the main factors influencing dryland wheat grain yield under mulching conditions compared to CK. 展开更多
关键词 dryland winter wheat plastic mulch spike number straw mulch
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Genomic selection of eight fruit traits in pear
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作者 Manyi Sun Mingyue Zhang +8 位作者 Satish Kumar Mengfan Qin Yueyuan Liu Runze Wang Kaijie Qi Shaoling Zhang Wenjing Chang Jiaming Li Jun Wu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期318-326,共9页
Genomic selection (GS) has the potential to improve selection efficiency and shorten the breeding cycle in fruit tree breeding. In this study,we evaluated the effect of prediction methods, marker density and the train... Genomic selection (GS) has the potential to improve selection efficiency and shorten the breeding cycle in fruit tree breeding. In this study,we evaluated the effect of prediction methods, marker density and the training population (TP) size on pear GS for improving its performance and reducing cost. We evaluated GS under two scenarios:(1) five-fold cross-validation in an interspecific pear family;(2) independent validation. Based on the cross-validation scheme, the prediction accuracy (PA) of eight fruit traits varied between 0.33 (fruit core vertical diameter)and 0.65 (stone cell content). Except for single fruit weight, a slightly better prediction accuracy (PA) was observed for the five parametrical methods compared with the two non-parametrical methods. In our TP of 310 individuals, 2 000 single nucleotide polymorphism (SNP) markers were sufficient to make reasonably accurate predictions. PAs for different traits increased by 18.21%-46.98%when the TP size increased from 50to 100, but the increment was smaller (-4.13%-33.91%) when the TP size increased from 200 to 250. For independent validation, the PAs ranged from 0.11 to 0.45 using rrBLUP method. In summary, our results showed that the TP size and SNP numbers had a greater impact on the PA than prediction methods. Furthermore, relatedness among the training and validation sets, and the complexity of traits should be considered when designing a TP to predict the test panel. 展开更多
关键词 PEAR PYRUS Prediction method TP size SNP marker number
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A dynamic regulation of nitrogen on floret primordia development in wheat
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作者 Zhen Zhang Yujing Li +6 位作者 Yuxun Wu Xiaoyu Zheng Xiaolei Guo Wan Sun Zhencai Sun Zhimin Wang Yinghua Zhang 《The Crop Journal》 SCIE CSCD 2024年第1期271-280,共10页
Nitrogen(N)fertilization is critical for spike and floret development,which affects the number of fertile florets per spike(NFFs).However,the physiological regulation of the floret development process by N fertilizati... Nitrogen(N)fertilization is critical for spike and floret development,which affects the number of fertile florets per spike(NFFs).However,the physiological regulation of the floret development process by N fertilization is largely unknown.A high temporal-resolution investigation of floret primordia number and morphology,dry matter,and N availability was conducted under three N fertilization levels:0(N0),120(N1)and 240(N2)kg ha^(−1).Interestingly,fertile florets at anthesis stage were determined by those floret primordia with meiotic ability at booting stage:meiotic ability was a threshold that predicted whether a floret primordium became fertile or abortive florets.Because the developmental rate of the 4th floret primordium in the central spikelet was accelerated and then they acquired meiotic ability,the NFFs increased gradually as N application increased,but the increase range decreased under N2.There were no differences in spike N concentration among treatments,but leaf N concentration was increased in the N1 and N2 treatments.Correspondingly,dry matter accumulation and N content of the leaf and spike in the N1 and N2 treatments was increased as compared to N0.Clearly,optimal N fertilization increased leaf N availability and transport of assimilates to spikes,and allowed more floret primordia to acquire meiotic ability and become fertile florets,finally increasing NFFs.There was no difference in leaf N concentration between N1 and N2 treatment,whereas soil N concentration at 0–60 cm soil layers was higher in N2 than in N1 treatment,implying that there was still some N fertilization that remained unused.Therefore,improving the leaf’s ability to further use N fertilizer is vital for greater NFFs. 展开更多
关键词 Fertile florets Floret primordia Grain number Meiotic ability Morphological development
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A stable staggered-grid finite-difference scheme for acoustic modeling beyond conventional stability limit
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作者 Jing-Yi Xu Yang Liu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期182-194,共13页
Staggered-grid finite-difference(SGFD)schemes have been widely used in acoustic wave modeling for geophysical problems.Many improved methods are proposed to enhance the accuracy of numerical modeling.However,these met... Staggered-grid finite-difference(SGFD)schemes have been widely used in acoustic wave modeling for geophysical problems.Many improved methods are proposed to enhance the accuracy of numerical modeling.However,these methods are inevitably limited by the maximum Courant-Friedrichs-Lewy(CFL)numbers,making them unstable when modeling with large time sampling intervals or small grid spacings.To solve this problem,we extend a stable SGFD scheme by controlling SGFD dispersion relations and maximizing the maximum CFL numbers.First,to improve modeling stability,we minimize the error between the FD dispersion relation and the exact relation in the given wave-number region,and make the FD dispersion approach a given function outside the given wave-number area,thus breaking the conventional limits of the maximum CFL number.Second,to obtain high modeling accuracy,we use the SGFD scheme based on the Remez algorithm to compute the FD coefficients.In addition,the hybrid absorbing boundary condition is adopted to suppress boundary reflections and we find a suitable weighting coefficient for the proposed scheme.Theoretical derivation and numerical modeling demonstrate that the proposed scheme can maintain high accuracy in the modeling process and the value of the maximum CFL number of the proposed scheme can exceed that of the conventional SGFD scheme when adopting a small maximum effective wavenumber,indicating that the proposed scheme improves stability during the modeling. 展开更多
关键词 Acoustic wave Staggered-grid finite-difference(SGFD) modeling Courant-friedrichs-lewy(CFL)number Stability
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Single‑cell sequencing reveals the reproductive variations between primiparous and multiparous Hu ewes
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作者 Ting Ge Yifan Wen +3 位作者 Bo Li Xiaoyu Huang Shaohua Jiang Enping Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期614-631,共18页
Background In the modern sheep production systems,the reproductive performance of ewes determines the economic profitability of farming.Revealing the genetic mechanisms underlying differences in the litter size is imp... Background In the modern sheep production systems,the reproductive performance of ewes determines the economic profitability of farming.Revealing the genetic mechanisms underlying differences in the litter size is important for the selection and breeding of highly prolific ewes.Hu sheep,a high-quality Chinese sheep breed,is known for its high fecundity and is often used as a model to study prolificacy traits.In the current study,animals were divided into two groups according to their delivery rates in three consecutive lambing seasons(namely,the high and low reproductive groups with≥3 lambs and one lamb per season,n=3,respectively).The ewes were slaughtered within 12 h of estrus,and unilateral ovarian tissues were collected and analyzed by 10×Genomics single-cell RNA sequencing.Results A total of 5 types of somatic cells were identified and corresponding expression profiles were mapped in the ovaries of each group.Noticeably,the differences in the ovary somatic cell expression profiles between the high and low reproductive groups were mainly clustered in the granulosa cells.Furthermore,four granulosa cell subtypes were identified.GeneSwitches analysis revealed that the abundance of JPH1 expression and the reduction of LOC101112291 expression could lead to different evolutionary directions of the granulosa cells.Additionally,the expression levels of FTH1 and FTL in mural granulosa cells of the highly reproductive group were significantly higher.These genes inhibit necroptosis and ferroptosis of mural granulosa cells,which helps prevent follicular atresia.Conclusions This study provides insights into the molecular mechanisms underlying the high fecundity of Hu sheep.The differences in gene expression profiles,particularly in the granulosa cells,suggest that these cells play a critical role in female prolificacy.The findings also highlight the importance of genes such as JPH1,LOC101112291,FTH1,and FTL in regulating granulosa cell function and follicular development. 展开更多
关键词 Granulosa cells Hu sheep Lambing number Ovarian somatic cells Single-cell RNA sequencing
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