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Adaptive convergence at the genomic level——prevalent, uncommon or very rare?

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National Science Review 2020年第6期7卷 947-951页

作者： Ziwen He Shaohua Xu suhua Shi School of Life Sciences Sun Yat-sen University

Convergent evolution is one of the central topics in evolutionary genetics [1].While there has been ample evidence of phenotypic convergence, the issue is whether each and any of the phenotypic convergences have an underlying cause in genic convergence [2,3]. Fortunately,the torrent of genomic data has made it possible to address the issue [4–8].Convergence can happen at multiple

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Molecular Population genetics of Rice Domestication

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Journal of Integrative Plant Biology 2007年第6期49卷 769-775页

作者： Tian Tang suhua Shi State Key Laboratory of Biocontrol School of Life Sciences Sun Yat-sen (Zhongshan) University Guangzhou 510275 China

Domestication is a selection process that genetically modifies species to meet human needs. A most intriguing feature of domestication is the extreme phenotypic diversification among breeds. What could be the ultimate source of such genetic variations？ Another notable outcome of artificial selection is the reduction In the fitness of domesticated species when they live In the wild without human assistance. The complete sequences of the two subspecies of rice cultlvars provide an opportunity to address these questions. Between the two subspecies, we found much higher rates of non-synonymous （N） than synonymous （S） substitutions and the N/S ratios are higher between cultivars than between wild species. Most interestingly, substitutions of highly dissimilar amino acids that are deleterious and uncommon between natural species are disproportionately common between the two subspecies of rice. We suggest strong selection in the absence of effective recombination may be the driving force, which we called the domestication-associated Hill-Robertson effect. These hitchhiking mutations may contribute to some fitness reduction in cultivars. Comparisons of the two genomes also reveal the existence of highly divergent regions in the genomes. Haplotypes in these regions often form highly polymorphic linkage blocks that are much older than speciation between wild species. genes from such regions could contribute to the differences between indica and japonica and are likely to be involved in the diversifying selection under domestication. Their existence suggests that the amount of genetic variation within the single progenitor species Oryza rufipogon may be insufficient to account for the variation among rice cultivars, which may come from a more inclusive gene pool comprising most of the A-genome wild species. genes from the highly polymorphic regions also provide strong support for the Independent domestication of the two subspecies. The genomic variation in rice has revealing i

关键词： rice population genetics domestication artificial selection admixture.

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of geotechnical Structures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses significant risks to the stability of geotechnical structures *** understanding of the liquefaction triggering,and the post-failure large deformation behaviour is essential for designing resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading is described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A staggered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San Fernando *** agreement for liquefaction triggering and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

genes and speciation: is it time to abandon the biological species concept?

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National Science Review 2020年第8期7卷 1387-1397页

作者： Xinfeng wang Ziwen He suhua Shi Chung-I Wu State Key Laboratory of Biocontrol Guangdong Key Lab of Plant Resources School of Life Sciences Sun Yat-Sen University Department of Ecology and Evolution University of Chicago

The biological species concept(BSC) is the cornerstone of neo-Darwinian thinking. In BSC, species do not exchange genes either during or after speciation. However, as gene flow during speciation is increasingly being reported in a substantial literature, it seems time to reassess the revered, but often doubted, *** to the common perception, BSC should expect substantial gene flow at the onset of speciation, not least because geographical isolation develops gradually. Although BSC does not stipulate how speciation begins, it does require a sustained period of isolation for speciation to complete its course. Evidence against BSC must demonstrate that the observed gene flow does not merely occur at the onset of speciation but continues until its completion. Importantly, recent genomic analyses cannot reject this more realistic version of BSC, although future analyses may still prove it wrong. The ultimate acceptance or rejection of BSC is not merely about a historical debate; rather, it is about the fundamental nature of species – are species(and, hence, divergent adaptations) driven by a relatively small number of genes, or by thousands of them? Many levels of biology, ranging from taxonomy to biodiversity, depend on this resolution.

关键词： speciation species concept gene flow geographical isolation allopatry

Theoretical Investigation of Negative Refraction in Metallic and Ferromagnetic Composites

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Wuhan University Journal of Natural Sciences 2004年第4期9卷 459-462页

作者： suhua LICheng-fang SchoolofPhysicsandTechnology.WuhanUniversity Wuhan430072Hubei.China SchoolofPhysicsandTechnology.WuhanUniversity Wuhan430072Hubei.China

A new design of LHM (left-handed material) is suggested, in which the wave vectork and the energy flowS (the Poynting vector) are in the opposite direction. Metallic cores or lines are coated with ferromagnetic layers to obtain negative permittivity and permeability. This design may bring some improvements over the binary design, such as higher homogeneity, smaller volume size, lower power loss, higher convenience and economy. The analytical expressions for the permittivity ε and permeability μ are shown to be negative in certain direction and frequency regions. Two specific structures are theoretically discussed and proved to be left-handed. Key words left-handed materials - negative refraction - NIM - LHM - artificial crystal CLC number O 438 Foundation item: Supported by the National Natural Science Foundation of China (10344002)Biography: SU Hua (1978-), male, Master candidate, research direction: information optics.

关键词： left-handed materials negative refraction NIM LHM artificial crystal

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Coordinated Optimization of Multi-energy generation Systems Considering the Health Damages of Coal-fired Pollutant Dispersion

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CSEE Journal of Power and Energy Systems 2022年第6期8卷 1613-1622页

作者： suhua Lou Yinhao Yang Yanjie Liang Yaowu Wu State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and TechnologyWuhan 430074China Power Dispatch and Control Center of China Southern Power grid Guangzhou 510623China

Pollutants emitted from coal-fired power plants lead to the deterioration of air quality in developing countries,and contribute to both mortality and *** improve air quality from power generation,new dispatch strategies incorporated with air pollution dispersion models should be *** paper takes into account the impact of meteorological variations on spatio-temporal dispersion of *** on the coal-fired pollutant concentration estimated by the gaussian plume dispersion model,exposure-response functions are used to quantify the resulting health ***,the corresponding economic costs of health damages are incorporated to penalize the power *** generation costs and economic costs of health damages,this paper formulates a twostage stochastic optimization model of a multi-energy generation system including coal units,gas units,and photovoltaic ***,numerical studies based on a modified IEEE 14-node system are performed for illustration and validation.

关键词： Coal-fired pollutant dispersion exposure-response functions gaussian plume model meteorological variations multi-energy generation system

Low-carbon Operation of Combined Heat and Power Integrated Plants Based on Solar-assisted Carbon Capture

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Journal of Modern Power Systems and Clean Energy 2022年第5期10卷 1138-1151页

作者： Xusheng guo suhua Lou Yaowu Wu Yongcan wang State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and TechnologyWuhan 430074China State grid Sichuan Electric Power Research Institute Chengdu 610041China

Accelerating the development of renewable energy and reducing CO_(2)emissions have become a general consensus and concerted action of all countries in the world. The electric power industry, especially thermal power industry, is the main source for fossil energy consumption and CO_(2)emissions. Since solvent-based post-combustion carbon capture technology would bring massive extra energy consumption, the application of solar-assisted carbon capture technology has attracted extensive attention. Due to the important role of coal-fired combined heat and power plants for serving residential and industrial heating districts, in this paper, the low-carbon operation benefits of combined heat and power integrated plants based on solar-assisted carbon capture(CHPIP-SACC) are fully evaluated in heat and power integrated energy system with a high proportion of wind power. Based on the selected integration scheme, a linear operation model of CHPIP-SACC is developed considering energy flow characteristics and thermal coupling interaction of its internal modules. From the perspective of system-level operation optimization, the day-ahead economic dispatch problem based on a mix-integer linear programming model is presented to evaluate the low-carbon benefits of CHPIP-SACC during annual operation simulation. The numerical simulations on a modified IEEE 39-bus system demonstrate the effectiveness of CHPIP-SACC for reducing CO_(2)emissions as well as increasing the downward flexibility. The impact of different solar field areas and unit prices of coal on the low-carbon operation benefits of CHPIP-SACC is studied in the section of sensitivity analysis.

关键词： Solar-assisted carbon capture CO_(2)emission reduction combined heat and power integrated plant heat and power integrated energy system wind power

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Efficient Priority-Flood depression filling in raster digital elevation models

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International Journal of Digital Earth 2019年第4期12卷 415-427页

作者： Hongqiang Wei guiyun Zhou suhua Fu Center for Information geoscience University of Electronic Science and Technology of ChinaChengduPeople’s Republic of China School of Resources and Environment University of Electronic Science and Technology of ChinaChengduPeople’s Republic of China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of SciencesYanglingPeople’s Republic of China Faculty of geographical Science Beijing Normal UniversityBeijingPeople’s Republic of China

Depressions in raster digital elevation models(DEM)present a challenge for extracting hydrological *** are commonly filled before subsequent algorithms are further *** existing algorithms for filling depressions,the Priority-Flood algorithm runs the *** this study,we propose an improved variant over the fastest existing sequential variant of the Priority-Flood algorithm for filling depressions in floating-point *** proposed variant introduces a series of improvements and greatly reduces the number of cells that need to be processed by the priority queue(PQ),the key data structure used in the *** proposed variant is evaluated based on statistics from 30 *** average,our proposed variant reduces the number of cells processed by the PQ by around 70%.The speed-up ratios of our proposed variant over the existing fastest variant of the Priority-Flood algorithm range from 31%to 52%,with an average of 45%.The proposed variant can be used to fill depressions in large DEMs in much less time and in the parallel implementation of the Priority-Flood algorithm to further reduce the running time for processing huge DEMs that cannot be dealt with easily on single computers.

关键词： Depression filling DEM drainage network

Carbon foam with microporous structure for high performance symmetric potassium dual-ion capacitor

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Journal of Energy Chemistry 2020年第4期29卷 129-138页

作者： Yanhong Feng suhua Chen Jue wang Bingan Lu School of Physics and Electronics Hunan UniversityChangsha 410082HunanChina State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082HunanChina

A novel carbon foam with microporous structure(CFMS),with the advantages of a simple fabrication process,low energy consumption,large specific surface area and high conductivity,has been prepared by a facile one-step *** addition,the carbon foam possesses suitable interlayer spacing in short range which is flexible to accommodate the deformation of carbon layer caused by the ion insertion and deinsertion at the charge and discharge ***,a low cost carbon-based symmetric potassium dual-ion capacitor(PDIC),which integrates the virtues of potassium ion capacitors and dual-ion batteries,is successfully established with CFMS as both the battery-type cathode and the capacitor-type *** displays a superior rate performance,an ultra-long cycle life(90%retention after 10000 cycles),and a high power density of 7800 W kg^-1 at an energy density of 39Whkg^-*** PDIC also exhibits excellent ultrafast charge and slow discharge properties,with a full charge in just 60 s and a discharge time of more than 3000 s.

关键词： Carbon foam Symmetric potassium-based dual-ion capacitor High energy/power density Ultrafast charge and slow discharge

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