检索结果-南通市图书馆

Evolutionary mechanisms and practical significance of reproductive success and clonal diversity in unisexual vertebrate polyploids

引用

Science China(life Sciences) 2024年第3期67卷 449-459页

作者： Meng Lu li Zhou Jian-fang Gui State Key Laboratory of Freshwater Ecology and Biotechnology Hubei Hongshan Laboratorythe Innovation Academy of Seed DesignInstitute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Sciences Beijing 100049China

Unisexual reproduction is generally relevant to polyploidy, and unisexual vertebrates are often considered an evolutionary “dead end” due to the accumulation of deleterious mutations and absence of genetic diversity. However, some unisexual polyploids have developed strategies to avoid genomic decay, and thus provide ideal models to unveil unexplored evolutionary mechanisms, from the reproductive success to clonal diversity creation. This article reviews the evolutionary mechanisms for overcoming meiotic barrier and generating genetic diversity in unisexual vertebrates, and summarizes recent research advancements in the polyploid Carassius complex. Gynogenetic gibel carp(Carassius gibelio) is a unique amphitriploid that has undergone a recurrent autotriploidy and has overcome the bottleneck of triploid sterility via gynogenesis. Recently, an efficient strategy in which ploidy changes, including from amphitriploid to amphitetraploid, then from amphitetraploid to novel amphitriploid, drive unisexual-sexual-unisexual reproduction transition and clonal diversity has been *** on this new discovery, multigenomic reconstruction biotechnology has been used to breed a novel strain with superior growth and stronger disease resistance. Moreover, a unique reproduction mode that combines both abilities of ameiotic oogenesis and sperm-egg fusion,termed as ameio-fusiongensis, has been discovered, and it provides an efficient approach to synthesize sterile allopolyploids. In order to avoid ecological risks upon escape and protect the sustainable property rights of the aquaculture seed industry, a controllable fertility biotechnology approach for precise breeding is being developed by integrating sterile allopolyploid synthesis and gene-editing *** review provides novel insights into the origin and evolution of unisexual vertebrates and into the attempts being made to exploit new breeding biotechnologies in aquaculture.

关键词： unisexual vertebrates polyploidy reproduction transition clonal diversity precise breeding genomic reconstruction controllable fertility

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Deep Video Harmonization by Improving Spatial-temporal Consistency

引用

Machine Intelligence Research 2024年第1期21卷 46-54页

作者： Xiuwen Chen li fang Long Ye Qin Zhang Key Laboratory of Media Audio and Video Ministry of Education Communication University of ChinaBeijing 100024China

Video harmonization is an important step in video editing to achieve visual consistency by adjusting foreground appear-ances in both spatial and temporal *** methods always only harmonize on a single scale or ignore the inaccuracy of flow estimation,which leads to limited harmonization *** this work,we propose a novel architecture for video harmoniza-tion by making full use of spatiotemporal features and yield temporally consistent harmonized *** introduce multiscale harmon-ization by using nonlocal similarity on each scale to make the foreground more consistent with the *** also propose a fore-ground temporal aggregator to dynamically aggregate neighboring frames at the feature level to alleviate the effect of inaccurate estim-ated flow and ensure temporal *** experimental results demonstrate the superiority of our method over other state-of-the-art methods in both quantitative and visual comparisons.

关键词： Harmonization temporal consistency video editing video composition nonlocal similarity

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Causal Analysis Between Rice Growth and Cadmium Accumulation and Transfer under Arbuscular Mycorrhizal Inoculation

引用

Rice science 2024年第2期31卷 226-236页

作者： ZHAO Ting WANG li YANG Jixian MA fang State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China

Cadmium(Cd)contamination in rice has been a serious threat to human *** investigate the effects of arbuscular mycorrhizal fungi(AMF)on the Cd translocation in rice,a controlled pot experiment was *** results indicated that AMF significantly increased rice biomass,with an increase of up to 40.0%,particularly in root biomass by up to 68.4%.Notably,the number of prominent rice individuals also increased,and their plasticity was enhanced following AMF *** led to an increase in the net photosynthetic rate and antioxidant enzyme activity of *** the AMF treatment group,the Cd concentration in the rice roots was significantly higher(19.1%‒68.0%)compared with that in the control ***,the Cd concentration in the rice seeds was lower in the AMF treatment group,indicating that AMF facilitated the sequestration of Cd in rice roots and reduced Cd accumulation in the *** coefficients varied across different treatments,suggesting that AMF inoculation reduced the direct impact of soil Cd concentration on the total Cd accumulation in *** translocation of Cd was consistently associated with simultaneous growth dilution and compensatory accumulation as a result of mycorrhizal *** study quantitatively analyzed this process through path analysis and clarified the causal relationship between rice growth and Cd transfer under the influence of AMF.

关键词： cadmium transfer dilution effect heavy metal immobilization mycorrhizal effect path analysis phenotypic plasticity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Optimal Operation with Dynamic Partitioning Strategy for Centralized Shared Energy Storage Station with Integration of Large-scale Renewable Energy

引用

Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 359-370页

作者： Jianlin li Zhijin fang Qian Wang Mengyuan Zhang Yaxin li Weijun Zhang Beijing Future Technology Innovation Centre for Electrochemical Energy Storage System Integration North China University of Technology Beijing China State Grid Fujian Electric Power Research Institute Fuzhou China

As renewable energy continues to be integrated into the grid,energy storage has become a vital technique supporting power system *** effectively promote the efficiency and economics of energy storage,centralized shared energy storage(SES)station with multiple energy storage batteries is developed to enable energy trading among a group of *** this paper,we propose the optimal operation with dynamic partitioning strategy for the centralized SES station,considering the day-ahead demands of large-scale renewable energy power *** implement a multi-entity cooperative optimization operation model based on Nash bargaining *** model is decomposed into two subproblems:the operation profit maximization problem with energy trading and the leasing payment bargaining *** distributed alternating direction multiplier method(ADMM)is employed to address the subproblems *** reveal that the optimal operation with a dynamic partitioning strategy improves the tracking of planned output of renewable energy entities,enhances the actual utilization rate of energy storage,and increases the profits of each participating *** results confirm the practicality and effectiveness of the strategy.

关键词： Shared energy storage(SES) dynamic partitioning strategy optimal operation Nash bargaining theory actual utilization rate of energy storage

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Flexible tuning of multifocal holographic imaging based on electronically controlled metasurfaces

引用

Photonics Research 2024年第1期12卷 61-69页

作者： OWEN ZENG CHENXIA li BO fang ZHI HONG XUFENG JING Institute of Optoelectronic Technology China Jiliang UniversityHangzhou 310018China Centre for THz Research China Jiliang UniversityHangzhou 310018China College of Metrology&Measurement Engineering China Jiliang UniversityHangzhou 310018China

Programmable hyper-coded holography has the advantage of being programmable as well as being flexibly *** coded metamaterials with excellent electromagnetic modulation capability and the ability to control the phase to modulate the spatial radiation field through external excitation in the form of switching can be used to realize low-cost digital *** design a 1-bit encoded programmable metasurface,which is electrically connected to control the PIN diode in the switching state and to switch the condition of each metasurface cell between“0”and“1.”Using the designed programmable metasurface,we can randomly encode the cell structure to realize single-focus focusing,multi-focusing,and simple holographic letter *** on the nonlinear holographic model,we employ the Gerchberg-Saxton improvement algorithm to modulate the energy distribution at the focus by adjusting the phase ***,we introduce the Fourier convolution principle to regulate the holographic imaging focus flexibly.

关键词： holographic letter excitation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Revealing Al-O/Al-F reaction dynamic effects on the combustion of aluminum nanoparticles in oxygen/fluorine containing environments:A reactive molecular dynamics study meshing together experimental validation

引用

Defence Technology（防务技术） 2024年第4期34卷 313-327页

作者： Gang li Chuande Zhao Qian Yu fang Yang Jie Chen Institute of Chemical Materials China Academy of Engineering Physics(CAEP)P.O.Box 919-311Mianyang 621900SichuanChina

Improving the energy conversion efficiency in metallic fuel(e.g.,Al)combustion is always desirable but challenging,which often involves redox reactions of aluminum(Al)with various mixed oxidizing *** instance,Al-O reaction is the most common pathway to release limited energy while Al-F reaction has received much attentions to enhance Al combustion ***,microscopic understanding of the Al-O/Al-F reaction dynamics remains unsolved,which is fundamentally necessary to further improve Al combustion *** this work,for the first time,Al-O/Al-F reaction dynamic effects on the combustion of aluminum nanoparticles(n-Al)in oxygen/fluorine containing environments have been revealed via reactive molecular dynamics(RMD)simulations meshing together combustion *** RMD simulation systems of Al core/O_(2)/HF,n-Al/O_(2)/HF,and n-Al/O_(2)/CF4 with oxygen percentage ranging from 0%to 100%have been *** n-Al combustion in mixed O_(2)/CF_4 environments have been conducted by constant volume combustion *** results show that Al-O reaction exhibits kinetic benefits while Al-F reaction owns thermodynamic benefits for n-Al *** n-Al/O_(2)/HF,Al-O reaction gives faster energy release rate than Al-F reaction(1.1 times).The optimal energy release efficiency can be achieved with suitable oxygen percentage of 10%and 50%for n-Al/O_(2)/HF and n-Al/O_(2)/CF_4,*** combustion experiments,90%of oxygen percentage can optimally enhance the peak pressure,pressurization rate and combustion ***,Al-O reaction prefers to occur on the surface regions while Al-F reaction prefers to proceed in the interior regions of n-Al,confirming the kinetic/thermodynamic benefits of Al-O/Al-F *** synergistic effect of Al-O/Al-F reaction for greatly enhancing n-Al combustion efficiency is demonstrated at atomicscale,which is beneficial for optimizing the combustion performance of metallic fuel.

关键词： Al-O/Al—F reaction Kinetic benefits Thermodynamic benefits Molecular dynamics Combustion

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Structural and magnetic properties of micropolycrystalline cobalt thin films fabricated by direct current magnetron sputtering

引用

International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 384-394页

作者： Kerui Song Zhou li Mei fang Zhu Xiao Qian Lei School of Materials Science and Engineering Central South UniversityChangsha 410083China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Hunan Key Laboratory of Super-Microstructure and Ultrafast Process School of Physics and electronicsCentral South UniversityChangsha 410083China Key Laboratory of Non-Ferrous Metal Materials Science and Engineering Ministry of EducationChangsha 410083China

Pure cobalt(Co)thin films were fabricated by direct current magnetron sputtering,and the effects of sputtering power and pres-sure on the microstructure and electromagnetic properties of the films were *** the sputtering power increases from 15 to 60 W,the Co thin films transition from an amorphous to a polycrystalline state,accompanied by an increase in the intercrystal pore ***,the resistivity decreases from 276 to 99μΩ·cm,coercivity increases from 162 to 293 Oe,and in-plane magnetic aniso-tropy *** the sputtering pressure decreases from 1.6 to 0.2 Pa,grain size significantly increases,resistivity significantly de-creases,and the coercivity significantly increases(from 67 to 280 Oe),which can be attributed to the increase in defect ***-pondingly,a quantitative model for the coercivity of Co thin films was *** polycrystalline films sputtered under pressures of 0.2 and 0.4 Pa exhibit significant in-plane magnetic anisotropy,which is primarily attributable to increased microstress.

关键词： cobalt thin film magnetron sputtering microstructure electromagnetic properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Unraveling the atomic interdiffusion mechanism of NiFe_(2_)O_(4)oxygen carriers during chemical looping CO_(2)conversion

引用

Carbon Energy 2024年第8期6卷 105-121页

作者： Da Song Yan lin Shiwen fang Yang li Kun Zhao Xinfei Chen Zhen Huang fang He Zengli Zhao Hongyu Huang Fanxing li Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhouChina School of Energy Science and Engineering University of Science and Technology of ChinaHefeiChina College of Mechanical and Electrical Engineering Zhongkai University of Agriculture and EngineeringGuangzhouChina College of Chemistry and Bioengineering Guilin University of TechnologyGuilinChina North Carolina State University RaleighNorth CarolinaUSA

By employing metal oxides as oxygen carriers,chemical looping demonstrates its effectiveness in transferring oxygen between reduction and oxidation environments to partially oxidize fuels into syngas and convert CO_(2)into ***,NiFe_(2_)O_(4)oxygen carriers have demonstrated remarkable efficiency in chemical looping CO_(2)***,the intricate process of atomic migration and evolution within the internal structure of bimetallic oxygen carriers during continuous high‐temperature redox cycling remains ***,the lack of a fundamental understanding of the complex ionic migration and oxygen transfer associated with energy conversion processes hampers the design of high‐performance oxygen ***,in this study,we employed in situ characterization techniques and theoretical calculations to investigate the ion migration behavior and structural evolution in the bulk of NiFe_(2_)O_(4)oxygen carriers during H2 reduction and CO_(2)/lab air oxidation *** discovered that during the H2 reduction step,lattice oxygen rapidly migrates to vacancy layers to replenish consumed active oxygen species,while Ni leaches from the material and migrates to the *** the CO_(2)splitting step,Ni migrates toward the core of the bimetallic oxygen carrier,forming Fe–Ni *** the air oxidation step,Fe–Ni migrates outward,creating a hollow structure owing to the Kirkendall effect triggered by the swift transfer of lattice *** metal atom migration paths depend on the oxygen transfer *** discoveries highlight the significance of regulating the release–recovery rate of lattice oxygen to uphold the structures and reactivity of oxygen *** work offers a comprehensive understanding of the oxidation/reduction‐driven atomic interdiffusion behavior of bimetallic oxygen carriers.

关键词： chemical looping CO_(2)splitting density functional theory in situ characterization ionic migration

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A Novel Fall Detection Framework Using Skip-DSCGAN Based on Inertial Sensor Data

引用

Computers, Materials & Continua 2024年第1期78卷 493-514页

作者： Kun fang Julong Pan lingyi li Ruihan Xiang College of Information Engineering China Jiliang UniversityHangzhou310018China

With the widespread use of Internet of Things(IoT)technology in daily life and the considerable safety risks of falls for elderly individuals,research on IoT-based fall detection systems has gainedmuch *** paper proposes an IoT-based spatiotemporal data processing framework based on a depthwise separable convolution generative adversarial network using skip-connection(Skip-DSCGAN)for fall *** method uses spatiotemporal data from accelerometers and gyroscopes in inertial sensors as input data.A semisupervised learning approach is adopted to train the model using only activities of daily living(ADL)data,which can avoid data imbalance ***,a quantile-based approach is employed to determine the fall threshold,which makes the fall detection frameworkmore *** proposed fall detection framework is evaluated against four other generative adversarial network(GAN)models with superior anomaly detection performance using two fall public datasets(SisFall&MobiAct).The test results show that the proposed method achieves better results,reaching 96.93% and 92.75% accuracy on the above two test datasets,*** the same time,the proposed method also achieves satisfactory results in terms ofmodel size and inference delay time,making it suitable for deployment on wearable devices with limited *** addition,this paper also compares GAN-based semisupervised learning methods with supervised learning methods commonly used in fall *** clarifies the advantages of GAN-based semisupervised learning methods in fall detection.

关键词： Fall detection skip-connection depthwise separable convolution generative adversarial networks inertial sensor

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Spatially explicit reconstruction of cropland cover in Europe from AD 1800 to 2000

引用

Science China Earth Sciences 2024年第9期67卷 2953-2971页

作者： Jun li Yu YE Xiuqi fang Diyang ZHANG Zhilei WU Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China College of Geographical Science Qinghai Normal UniversityXining 810016China

One of the challenges in global change research is the significant uncertainty in global historical land use and land cover(LUCC)datasets,which are widely used as foundational *** addition to the regional cropland area reconstructions,improving the grid allocation method is another feasible way to raise the reliability of historical LUCC *** this study,an integrated reconstruction of the national cropland areas over the past 200 years was developed for 36 European *** that,the allocation algorithm was built using physiogeographic variables and historical city sites for accounting for land suitability and cultivation preferences,***,cropland data in Europe with a spatial resolution of 5′×5′at five time sections from AD 1800 to 2000 were generated using the optimal allocation algorithm in accordance with the stages of the regional *** results were as follows:(1)The dominant factors governing the distribution of croplands in Europe vary at different agricultural stages,but the results can be merged *** suitability was more optimal for allocation during the modern agricultural stage(AD 1950 and 2000);the priority index combined with land suitability and cultivation preference was more reasonable for allocation during the traditional agricultural stage(AD 1800).The average of the allocations by priority index and the land suitability could be adopted as the allocation results during the transitional stage(AD 1850 and 1900)because the grids for absolute differences within±10 and±20 percentage points between the results obtained from the above two allocations were above 80% and 95%,respectively,which means the two allocation results could be merged.(2)Over the past 200 years,the total cropland area in Europe first increased to a peak in AD 1900 and then ***,the centre of the higher cropland fraction shifted from the western part of Europe in AD 1800 to the eastern part of the continent after AD 1950.(3)

关键词： Land use and land cover change Historical cropland Gridding allocation Europe Past 200 years

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：