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A historical review of hybrid rice breeding

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Journal of Integrative Plant Biology 2024年第3期66卷 532-545页

作者： Xiaoming zheng Fei wei cheng cheng Qian Qian State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Yazhouwan National Laboratory Sanya City 572024China

The development of germplasm resources and advances in breeding methods have led to steady increases in yield and quality of rice (Oryza sativa L.). Three milestones in the recent history of rice breeding have contributed to these increases: dwarf rice breeding, hybrid rice breeding, and super rice breeding. On the 50th anniversary of the success of three-line hybrid rice,we highlight important scientific discoveries in rice breeding that were made by Chinese scientists and summarize the broader history of the field. We discuss the strategies that could be used in the future to optimize rice breeding further in the hope that China will continue to play a leading role in international rice breeding.

关键词： Chinese experience dwarf breeding hybrid rice breeding super rice breeding

Field-Aligned Electrons in Polar Region Observed by Cluster on 30 September 2001

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Chinese Physics Letters 2012年第9期29卷 244-247页

作者： ZHANG Zi-Ying SHI Jian-Kui cheng zheng-wei Andrew Fazakerley State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190 MSSL University College LondonUK

The physical process in the Earth's polar region is very complex and still needs to be further *** the data from Cluster satellite measurement,an analysis on field-aligned electrons in the mid-latitude cusp on 30 September 2001 has been *** satellite observed a down-flowing electron event in the low-latitude boundary and a sequential up-flowing electron event in the high-latitude boundary of the cusp *** down-flowing electron had a velocity as high as 500 km/s and a flux of 2.0×10^(9) cm^(-2)-s^(-1).The up-flowing electron had a velocity up to 1200 km/s and a flux of 4.9×10^(9) cm^(-2)-s^(-1).Both the velocity and the flux observed in this event are the maximum values of the up-flowing electrons observed by all satellites to *** electron is the main contributor for the field-aligned current in this *** physical mechanism is also *** down-flowing electron in the low-latitude boundary of the cusp region may result from solar wind injecting during the southward IMF,and the up-flowing electrons in the high-latitude boundary of cusp may result from mirroring of the solar wind,or from the ionospheric up-flowing electrons which have been accelerated.

关键词： latitude Earth flowing

Emergent symmetry in quantum phase transition:From deconfined quantum critical point to gapless quantum spin liquid

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Science Bulletin 2024年第2期69卷 190-196页

作者： Wen-Yuan Liu Shou-Shu Gong wei-Qiang Chen zheng-cheng Gu Department of Physics The Chinese University of Hong KongHong KongChina Division of Chemistry and Chemical Engineering California Institute of TechnologyPasadena CA 91125USA School of Physical Sciences Great Bay UniversityDongguan 523000China Great Bay Institute for Advanced Study Dongguan 523000China Department of Physics and Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices Southern University of Science and TechnologyShenzhen 518055China

The emergence of exotic quantum phenomena in frustrated magnets is rapidly driving the development of quantum many-body physics,raising fundamental questions on the nature of quantum phase *** we unveil the behaviour of emergent symmetry involving two extraordinarily representative phenomena,i.e.,the deconfined quantum critical point(DQCP)and the quantum spin liquid(QSL)*** large-scale tensor network simulations,we study a spatially anisotropic spin-1/2 square-lattice frustrated antiferromagnetic(AFM)model,namely the J1x-J1y-J2 model,which contains anisotropic nearestneighbor couplings J1x,J1y and the next nearest neighbor coupling *** small J1y/J1x,by tuning J2,a direct continuous transition between the AFM and valence bond solid phase is *** growing J1y/J1x,a gapless QSL phase gradually emerges between the AFM and VBS *** observe an emergent O(4)symmetry along the AFM–VBS transition line,which is consistent with the prediction of DQCP *** surprisingly,we find that such an emergent O(4)symmetry holds for the whole QSL–VBS transition line as *** findings reveal the intrinsic relationship between the QSL and DQCP from categorical symmetry point of view,and strongly constrain the quantum field theory description of the QSL *** phase diagram and critical exponents presented in this paper are of direct relevance to future experiments on frustrated magnets and cold atom systems.

关键词： Tensor network Quantum phase transition Emergent symmetry Quantum spin liquid Deconfined quantum critical point Anisotropic

Field-Aligned Currents at the PSBL on 17 August 2001 Storm: Relationships with solar Wind Conditions

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Chinese Physics Letters 2011年第9期28卷 267-270页

作者： cheng zheng-wei SHI Jian-Kui ZHANG Tie-Long WANG Sheng-Guo LIU Zhen-Xing State Key Laboratory of Space Weather CSSAR/CASBeijing 100190 Space Research Institute Austrian Academy of SciencesGrazAustria Beijing Institute of Applied Meteorology Beijing 100083

Using magnetic field and plasma data acquired with Cluster spacecrafts,we investigate the relationship between the field-aligned currents(FACs)at the plasma sheet boundary layer(PSBL)and solar wind dynamic pressure,as well as the interplanetary magnetic field(IMF)By on 17 August 2001 *** studies reveal that FAC density at the PSBL in the magnetotail in the storm time is controlled mainly by the solar wind dynamic pressure rather than IMF *** FACs at the PSBL are associated with the low−altitude region-1 current and have the same polarity as region-1 current in the dawn *** the polar region,the footprints of the FACs at the PSBL expand *** data analysis also shows that a very strong FAC with a density over 40 nA·m^(−2) appeared in this storm time when a substorm just occurred.

关键词： storm altitude Wind

Investigation of wake-induced vibration interference between two staggered wave-cone cylinders at subcritical Reynolds number

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Journal of Hydrodynamics 2024年第2期36卷 378-393页

作者： Lin Zou Di-wei Liu Jian Liu Hong-cheng Zuo Yin-huan zheng Hao Xia School of Mechanical and Electronic Engineering Wuhan University of TechnologyWuhan430070China Department of Aeronautical and Automotive Engineering Loughborough UniversityLoughboroughUK

The wake induced vibration(WIV)of a one-and two-degree-of-freedom(1DOF,2DOF)downstream wave-cone cylinder(WCC)behind a stationary equal-size upstream wave-cone cylinder in the staggered arrangement is numerically investigated at subcritical Reynolds number of 3900 by using shear stressed transfer(SST)k-ωturbulence *** streamwise pitch ratios(P/Dm)vary from 4 to 6 with a fixed incident angleα=8°.Experimental measurements were also performed for the validation of the present numerical *** is found that the largest vibration amplitude in crossflow direction occurred at P/Dm=4,Ur=8 with small difference of streamwise vibration at P/Dm=4,*** from single wavy-cone cylinder(SWCC),the downstream flexible one of a pair staggered WCCs got larger vibration amplitude during phase switching stage instead of in-phase *** upstream wake will suppress the triple frequency of main frequency in the power spectra density(PSD)functions of Cl but stimulate the double one of *** intriguing vibration mechanism happened in all 2DOF cases where the trajectory of downstream WCC is a significant ellipse rather than a figure of *** transformation of phase switching and the variation of the main frequency of drag coefficient(Cd)can be explained by the vortex-shedding modes of downstream WCC.

关键词： Two wave-cone cylinders staggered arrangement wake induced vibration phase switching vortex shedding

Recent progress in functional modification and crosslinking of bioprosthetic heart valves

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Regenerative Biomaterials 2024年第1期3卷 1-16页

作者： cheng zheng Li Yang Yunbing Wang National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China

Valvular heart disease(VHD),clinically manifested as stenosis and regurgitation of native heart valve,is one of the most prevalent cardiovascular diseases with high *** valve replacement surgery has been recognized as golden standard for the treatment of *** to the clinical application of transcatheter heart valve replacement technic and the excellent hemodynamic performance of bioprosthetic heart valves(BHVs),implantation of BHVs has been increasing over recent years and gradually became the preferred choice for the treatment of ***,BHVs might fail within 10-15 years due to structural valvular degeneration(SVD),which was greatly associated with drawbacks of glutaraldehyde crosslinked BHVs,including cytotoxicity,calcification,component degradation,mechanical failure,thrombosis and immune *** prolong the service life of BHVs,much effort has been devoted to overcoming the drawbacks of BHVs and reducing the risk of *** this review,we summarized and analyzed the research and progress on:(i)modification strategies based on glutaraldehyde crosslinked BHVs and(ii)nonglutaraldehyde crosslinking strategies for BHVs.

关键词： bioprosthetic heart valves modification crosslinking anticalcification antithrombosis

On-surface synthesis and characterization of polyynic carbon chains

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National Science Review 2024年第3期11卷 192-199页

作者： Wenze Gao wei zheng Luye Sun Faming Kang zheng Zhou wei Xu Interdisciplinary Materials Research Center School of Materials Science and Engineering Tongji University

Carbyne, an elusive sp-hybridized linear carbon allotrope, has fascinated chemists and physicists for decades. Due to its high chemical reactivity and extreme instability, carbyne was much less explored in contrast to the sp2-hybridized carbon allotropes such as graphene. Herein, we report the on-surface synthesis of polyynic carbon chains by demetallization of organometallic polyynes on the Au（111） surface;the longest one observed consists of ～60 alkyne units（120 carbon atoms）. The polyynic structure of carbon chains with alternating triple and single bonds was unambiguously revealed by bond-resolved atomic force microscopy. Moreover, an atomically precise polyyne, C14, was successfully produced via tip-induced dehalogenation and ring-opening of the decachloroanthracene molecule(C14Cl10) on a bilayer NaCl/Au（111） surface at 4.7 K, and a band gap of 5.8 eV was measured by scanning tunnelling spectroscopy,in a good agreement with the theoretical HOMO–LUMO gap（5.48 eV）.

关键词： polyyne scanning probe microscopy carbon allotrope on-surface synthesis organometallic polyyne

Relationship between dietary niacin intake and erectile dysfunction:a population-based study

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Asian Journal of Andrology 2024年第4期26卷 382-388页

作者： wei-Long Lin cheng zheng Hao-Xu Wang wei Zhang Ming-En Lin Department of Urology The First Affiliated Hospital of Shantou University Medical CollegeMedical College of Shantou UniversityShantou 515041China The Second School of Clinical Medicine Southern Medical UniversityGuangzhou 510260China.

Existing research on the precise link between dietary niacin intake and erectile dysfunction(ED)is ***,this study aimed to investigate the potential association between dietary niacin intake and the risk of *** logistic regression and restricted cubic splines(RCSs)were used to examine the relationship between dietary niacin intake and *** interaction analysis was performed to assess the impact of different subgroups on the study *** addition,1:1 propensity score matching(PSM)was employed to adjust for potential confounding factors,ensuring the reliability of the *** analyzed data were collected from the 2001–2004 National Health and Nutrition Examination Survey(NHANES)in the *** study encompassed 3184 adults,among whom 863 participants were identified as having *** adjustments for potential confounders,the findings revealed that higher niacin intake,specifically in the highest tertile,was associated with a decreased risk of ED compared to that in the lowest tertile,showing an odds ratio(OR)of 0.56(95%confidence interval[CI]:0.37–0.85).Analysis of dose–response curves illustrated a negative correlation between dietary niacin intake and the risk of *** and interaction analyses fortified the consistency of these ***,PSM corroborated the validity of the *** study suggests an inverse association between dietary niacin intake and the risk of ***,establishing a cause-and-effect relationship remains elusive,and defining the safe threshold of niacin intake to prevent ED requires further investigation.

关键词： dietary niacin erectile dysfunction National Health and Nutrition Examination Survey propensity score matching

Design and experiment of anti-adhesion rototiller based on staggered double-roller scraping

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 165-175页

作者： Jian cheng Junfang Xia Kan zheng Guoyang Liu Youshuai wei Juan Zou College of Engineering Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Agricultural Equipment in Mid-lower Reaches of Yangtze River Ministry of Agriculture and Rural AffairsWuhan 430070China Hubei academy of agricultural sciences institute of food crops Wuhan 430070China

In order to solve the serious problem of soil adhering blade roller in the middle and lower reaches of Yangtze River,the anti-adhesion rototiller based on staggered double-roller scraping(ARSDS)was designed by mechanical scraping *** volume equation for scraping the soil adhesion part with staggered rotary blades was *** mechanical conditions for separation of soil adhesion part from blade roller were clarified,and the contact time between rotary blade and soil during rotary tillage was *** this way,the key parameters affecting soil adhering on and separating from the blade roller were determined,which were rotational speed,cutting pitch and tillage *** spatial and temporal trajectory changes for the sidelong section edge of staggered rotary blades were analyzed,so that the rotary blade arrangement was *** the discrete element method,selecting the soil adhesion mass on the staggered blade rollers as the response value established prediction model by Box-Behnken design *** example,taking the tillage depth of 14 cm for wheat cultivation in the middle and lower reaches of Yangtze River,the optimal combination of parameters was determined to be 230 r/min and 10 cm for rotational speed and cutting pitch,*** this time,the soil adhesion mass was 4566.67 *** the meantime,the process of soil particles adhering staggered blade rollers and rotary blades scraping off the adhering soil were *** experiments have shown that the operation quality of ARSDS met the requirements of rototiller performance *** the rice stubble field of high water moisture,the soil adhesion mass was 13.455 kg and 38.215 kg for ARSDS and conventional rototiller,respectively,which indicated that ARSDS effectively reducing soil adhesion *** research results can provide technical support for the design of rototiller reducing soil adhesion in the agricultural areas of the middle and lower reaches of the Yangtze River.

关键词： rice stubble field rotary tillage reducing soil adhesion staggered double-roller discrete element method