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

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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 revealed.Based 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 techniques.This 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

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An explainable framework for load forecasting of a regional integrated energy system based on coupled features and multi-task learning

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Protection and Control of Modern Power Systems 2022年第1期7卷 349-362页

作者： Kailang Wu Jie Gu lu meng Honglin Wen Jinghuan Ma School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina

To extract strong correlations between different energy loads and improve the interpretability and accuracy for load forecasting of a regional integrated energy system(RIES),an explainable framework for load forecasting of an RIES is proposed.This includes the load forecasting model of RIES and its interpretation.A coupled feature extracting strat-egy is adopted to construct coupled features between loads as the input variables of the model.It is designed based on multi-task learning(MTL)with a long short-term memory(LSTM)model as the sharing layer.Based on SHapley Additive exPlanations(SHAP),this explainable framework combines global and local interpretations to improve the interpretability of load forecasting of the RIES.In addition,an input variable selection strategy based on the global SHAP value is proposed to select input feature variables of the model.A case study is given to verify the effectiveness of the proposed model,constructed coupled features,and input variable selection strategy.The results show that the explainable framework intuitively improves the interpretability of the prediction model.

关键词： Load forecasting Regional integrated energy system Coupled feature SHapley additive exPlanations Interpretability of deep learning

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Development of lunar regolith composite and structure via laser-assisted sintering

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Frontiers of Mechanical Engineering 2022年第1期17卷 178-187页

作者： Hua ZHAO lu meng Shaoying LI Jihong ZHU Shangqin YUAN Weihong ZHANG State IJR Center of Aerospace Design and Additive Manufacturing School of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Beijing Institute of Radio Measurement Beijing 100854China Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi'an 710072China Unmanned System Research Institute Northwestern Polytechnical UniversityXi’an 710072China

Aiming at the exploration and resource utilization activities on the Moon,in situ resource utilization and in situ manufacturing are proposed to minimize the dependence on the ground transportation supplies.In this paper,a laser-assisted additive manufacturing process is developed to fabricate lunar regolith composites with PA12/SiO2 mixing powders.The process parameters and composite material compositions are optimized in an appropriate range through orthogonal experiments to establish the relationship of process–structure–property for lunar regolith composites.The optimal combination of composite material compositions and process parameters are mixing ratio of 50/50 in volume,laser power of 30 W,scanning speed of 3500 mm/s,and scanning hatch space of 0.2 mm.The maximum tensile strength of lunar regolith composites reaches 9.248 MPa,and the maximum depth of surface variation is 120.79μm,which indicates poor powder fusion and sintering quality.Thereafter,the mechanical properties of laser-sintered lunar regolith composites are implemented to the topology optimization design of complex structures.The effectiveness and the feasibility of this laser-assisted process are potentially developed for future lightweight design and manufacturing of the solar panel installed on the lunar rover.

关键词： in situ manufacturing laser-assisted powder fusion process mechanical properties topological structure design

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考虑变井阻的多元复合地基固结理论研究

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工程力学 2024年第6期41卷 44-54页

作者：白垚卢萌盟杨康赵明中国矿业大学力学与土木工程学院江苏徐州221116 中国矿业大学深部岩土力学与地下工程国家重点实验室江苏徐州221116 浙江木石建设项目管理咨询有限公司浙江杭州311199

该文以塑料排水板联合水泥搅拌桩多元复合地基为研究对象,通过假定排水板的渗透系数随时间呈指数型衰减,考虑了排水板在固结过程中的淤堵效应对地基固结性状的影响。同时,该文还考虑排水板的涂抹效应、水泥搅拌桩的扰动效应以及土体的径... 详细信息

该文以塑料排水板联合水泥搅拌桩多元复合地基为研究对象,通过假定排水板的渗透系数随时间呈指数型衰减,考虑了排水板在固结过程中的淤堵效应对地基固结性状的影响。同时,该文还考虑排水板的涂抹效应、水泥搅拌桩的扰动效应以及土体的径-竖向耦合渗流,推导得出多元复合地基的固结控制方程及其解答。通过与已有解答和现场试验的对比分析,验证该文解答的正确性。最后,采用参数敏感性分析法对多元复合地基固结性状进行研究。研究结果表明:复合地基井阻因子θ对固结后期影响较大,当θ值较大时,径向渗流由于排水板的淤堵效应将提前终止,最终仅由竖向渗流使得地基达到完全固结;初始渗透系数k_0越大,井阻因子θ越小,涂抹作用越弱,板和桩的置换率越高,复合地基固结速率就越快。

关键词：多元复合地基排水板变井阻效应固结淤堵效应

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多元经营与主业坚守:出版传媒上市公司高质量发展研究

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编辑之友 2024年第1期32卷 54-60页

作者：陆朦朦崔波浙江传媒学院新闻与传播学院浙江杭州310018

党的二十大报告提出,“高质量发展是全面建设社会主义现代化国家的首要任务”。高质量发展是“十四五”乃至更长时期中国经济社会发展的主题。出版传媒上市公司是中国出版业高质量发展的微观基础,也是出版业中国式现代化进程的实践者和... 详细信息

党的二十大报告提出,“高质量发展是全面建设社会主义现代化国家的首要任务”。高质量发展是“十四五”乃至更长时期中国经济社会发展的主题。出版传媒上市公司是中国出版业高质量发展的微观基础,也是出版业中国式现代化进程的实践者和见证者,把握和分析我国出版传媒上市公司既有的主业营收结构及多元化经营的实际效果,是促进出版传媒企业高质量发展的基本前提。文章选取我国依托出版发行集团上市的20家出版传媒上市公司2018年至2023年上半年财务数据,从业务结构、区域结构、内部结构、输出结构四个维度,探析出版传媒上市公司高质量发展的营收现状。在此基础上,从多元经营与主业坚守的双向角度分析出版传媒上市公司高质量发展面临的挑战与困境,并针对性地提出有效的突破方案和路径。

关键词：高质量发展出版传媒上市公司多元经营营收结构

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Civil gas energy accidents in China from 2012-2021

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Journal of Safety Science and Resilience 2023年第4期4卷 348-357页

作者： Lei Pang Wei Li Kai Yang lu meng Jiansong Wu Jinglun Li Lishun Ma Sisi Chen Yan Liang School of Safety Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Research Institute of Macro-Safety Science University of Science and Technology BeijingBeijing 100083China Beijing Academy of Safety Engineering and Technology Beijing 102617China School of Emergency Management and Safety Engineering China University of Mining&TechnologyBeijing 100083China

In this study,civil gas energy accidents reported by the China Gas Network and related organizations from 2012 to 2021 were collected,and a comprehensive multidimensional correlation analysis was conducted considering factors such as accident timing,geography,causes,and casualties.The results identified July and August,Mondays and Sundays,and the morning,mid-day,and evening cooking times as the high-incidence months,days,and times for gas accidents,respectively.Gas accidents were found to occur more frequently in eastern coastal areas,provincial capitals,and larger cities,while residential and construction sites were identified as high-risk areas for gas accidents.Explosions were the most prevalent type of gas accident,followed by leaks,fires,and poisoning.Third-party construction and valve issues were identified as the primary factors contributing to gas leakage,whereas cooking was identified as the most common ignition source.An analysis of the Pearson correlation coefficient indicated a significant correlation among the gas accident factors.Moreover,a time-series prediction model was developed to forecast gas accidents in China,with the results demonstrating fluctuating gas accidents.This study proposes targeted preventive measures in terms of publicity,education,equipment,and facilities to provide scientific support to government units to improve civil gas energy security measures.

关键词： Gas accident Accident statistics Accident cause Accident prediction Preventive measures

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CFD analysis of a CiADS fuel assembly during the steam generator tube rupture accident based on the LBEsteamEulerFoam

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Nuclear Science and Techniques 2023年第10期34卷 136-147页

作者： Yun-Xiang Li lu meng Song Li Zi-Nan Huang Di-Si Wang Bo Liu You-Peng Zhang Tian-Ji Peng lu Zhang Xing-Kang Su Wei Jiang Institute of Modern Physics Fudan UniversityShanghai 200433China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516003China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

Steam generator tube rupture(SGTR) accident is an important scenario needed to be considered in the safety analysis of lead-based fast reactors. When the steam generator tube breaks close to the main pump, water vapor will enter the reactor core, resulting in a two-phase flow of heavy liquid metal and water vapor in fuel assemblies. The thermal-hydraulic problems caused by the SGTR accident may seriously threaten reactor core's safety performance. In this paper, the open-source CFD calculation software OpenFOAM was used to encapsulate the improved Euler method into the self-developed solver LBEsteamEulerFoam. By changing different heating boundary conditions and inlet coolant types, the two-phase flow in the fuel assembly with different inlet gas content was simulated under various accident conditions. The calculation results show that the water vapor may accumulate in edge and corner channels. With the increase in inlet water vapor content, outlet coolant velocity increases gradually. When the inlet water vapor content is more than 15%, the outlet coolant temperature rises sharply with strong temperature fluctuation. When the inlet water vapor content is in the range of 5–20%, the upper part of the fuel assembly will gradually accumulate to form large bubbles. Compared with the VOF method, Euler method has higher computational efficiency. However, Euler method may cause an underestimation of the void fraction, so it still needs to be calibrated with future experimental data of the two-phase flow in fuel assembly.

关键词： Steam generator tube rupture CiADS CFD simulations Two-phase flow

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典型城市不同河流沉积物中抗生素抗性基因的时空分布特征:以石家庄为例

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环境科学 2024年第6期45卷 3176-3185页

作者：赵波宋圆梦卢梦淇白寅虎陈昊达高赛王琳静张璐璐崔建升河北科技大学环境科学与工程学院石家庄050000 河北省污染防治生物技术实验室石家庄050000 河北省水利规划设计研究院有限公司石家庄050021

河流是抗生素抗性基因(ARGs)的重要储库.然而,目前有关河流中ARGs的研究多集中在其时空分布,而较少对同一区域城市和农村河流中ARGs的种类和丰度进行比较.鉴于此,以石家庄市不同河流为例,分别在2020年12月和2021年4月,选取了2条农村河流... 详细信息

河流是抗生素抗性基因(ARGs)的重要储库.然而,目前有关河流中ARGs的研究多集中在其时空分布,而较少对同一区域城市和农村河流中ARGs的种类和丰度进行比较.鉴于此,以石家庄市不同河流为例,分别在2020年12月和2021年4月,选取了2条农村河流和3条城市河流,布设了15个采样点,采集了各个样点的沉积物,运用宏基因组测序技术分析了各样点沉积物中ARGs的种类和丰度,比较了城市和农村河流沉积物中ARGs的时空差异.结果表明:①在城市和农村河流中分别检出162种(4 776±4 452,丰度,下同)和79种ARGs(1 043±632),ARGs种类和丰度均呈城市>农村的趋势;②在城市河流中磺胺类(SAs,27%)、氨基糖苷类(AGs,26%)和多药类(MDs,15%) ARGs的相对丰度最高;而在农村河流中MDs类ARGs的相对丰度最高(65%),且城市河流中ARGs的复杂程度高于农村河流.③城市河流中SAs、AGs、MDs、四环素类(TCs)、利胆醇类(PNs)、大环内酯类(MLS)、β-内酰胺类(β-lactams)和二氨基嘧啶类(DAPs)ARGs间呈显著正相关(P <0.01),而糖肽类(GPs)ARGs与各类ARGs呈显著负相关(P <0.05和P <0.01);而在农村河流中MDs和SAs类ARGs呈显著正相关(P <0.05),氨基香豆素类(ACs)ARGs与肽类(PTs)、利福霉素类(RMs)和磷霉素类(FMs)ARGs呈显著负相关(P <0.05和P <0.01);④在时间分布上,城市河流12月和4月分别检出162种(4 776±4 452)和148种(5 673±5 626)ARGs;而农村河流12月和4月分别检出79种(1 043±632)和46种(467±183)ARGs;⑤RDA分析结果表明,城市和农村河流中的ARGs均呈时间分布差异;相关分析表明城市河流主要与工业企业数量显著相关,而农村河流则主要与牧业产值显著相关.总体而言,通过比较城市和农村河流中ARGs的时空异质性,识别其主要社会影响因子,可为后续河流中ARGs风险管控提供数据支撑.

关键词：抗生素抗性基因(ARGs) 时空分布宏基因组城市河流农村河流社会经济因子

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阿勒泰地区生境质量的时空演变及其驱动因素

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北京林业大学学报 2024年第3期46卷 27-39页

作者：卢梦王鹤松荀雪北京林业大学生态与自然保护学院北京100083 新疆农业大学林学与风景园林学院新疆乌鲁木齐830052

【目的】揭示阿勒泰地区生境质量时空变化特征及其驱动机制,为当地生态环境保护和可持续发展提供科学支撑。【方法】基于1990—2021年逐年土地利用数据,运用ArcGIS和InVEST模型定量分析了阿勒泰地区土地利用和生境质量的时空变化特征,... 详细信息

【目的】揭示阿勒泰地区生境质量时空变化特征及其驱动机制,为当地生态环境保护和可持续发展提供科学支撑。【方法】基于1990—2021年逐年土地利用数据,运用ArcGIS和InVEST模型定量分析了阿勒泰地区土地利用和生境质量的时空变化特征,并探究生境质量指数的驱动因子。【结果】(1)阿勒泰地区土地利用类型以裸地和草地为主,主要分布于中部和南部,森林主要分布在研究区西北部,1990—2021年土地利用类型发生较大的变化,主要表现为裸地和草地之间的相互转化以及二者转化为耕地、森林和建筑用地,其间草地面积大幅度下降,而耕地、森林、建筑用地面积有较大上升。(2)空间格局上,阿勒泰地区的生境质量呈现出西北和北部地区高、南部地区低的空间特征,生境质量高值区主要分布在西北部森林、草地以及水体区域,低值区主要分布在南部裸地区域。同时,1990—2021年间生境质量平均值由0.513降至0.508。(3)土地利用程度和潜在蒸散发是驱动阿勒泰地区生境质量的两个主要因子,二者均与生境质量呈现显著负相关关系,年均温及年降水量与生境质量的相关性则较弱。【结论】阿勒泰地区生境质量整体呈轻度下降趋势,且与土地利用程度显著相关。未来应继续推进林草生态治理,优化土地利用结构。研究结果有助于增进对当地生境质量长时间序列动态变化过程的理解,可为阿勒泰地区以及其他西北干旱区的生态建设和产业发展评估提供决策支持。

关键词：阿勒泰地区土地利用变化 InVEST模型生境质量驱动因子

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超重力技术强化工业废水脱碳研究

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现代化工 2024年第4期44卷 216-219页

作者：赵泽盟李潇孟陆许强中煤能源研究院有限责任公司陕西西安710054 中煤西安设计工程有限责任公司陕西西安710054 陕西化工研究院有限公司陕西西安710054 陕西延长青山科技工程股份有限公司陕西西安710054

采用超重力设备RPB代替脱碳塔对实际工业废水进行脱碳。结果表明,使用RPB进行脱碳的效果、加药量和设备体积均优于常规脱碳塔。但是,RPB的运行费用高出常规脱碳塔15%。通过阐述RPB设备在工业废水脱碳过程中的优劣,为未来工业废水零排放... 详细信息

采用超重力设备RPB代替脱碳塔对实际工业废水进行脱碳。结果表明,使用RPB进行脱碳的效果、加药量和设备体积均优于常规脱碳塔。但是,RPB的运行费用高出常规脱碳塔15%。通过阐述RPB设备在工业废水脱碳过程中的优劣,为未来工业废水零排放项目脱碳工艺的选取提供参考。

关键词：超重力脱碳传质性能运行成本零排放

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