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Unveiling an ancient whole-genome duplication event in Stentor,the model unicellular eukaryotes

Science China Life Sciences 2025年

作者： Weibo Zheng Chao Li Zhaorui Zhou xiao Chen Michael Lynch Ying Yan School of Life Sciences Ludong University Key Laboratory of Evolution & Marine Biodiversity (Ministry of Education) and Institute of Evolution & Marine Biodiversity Ocean University of China Biodesign Center for Mechanisms of Evolution Arizona State University Marine College Shandong University

Whole-genome duplication(WGD) events are widespread across eukaryotes and have played a significant role in moulding the genetic architectures of diverse organisms. In the present study, the newly sequenced genome of a giant ciliated protist, Stentor roeselii, provides an opportunity for the analysis of the collinearity and retention of reciprocal best-hit genes between two Stentor species. As a main result, we have unveiled a previously undetected ancient WGD event shaping the genome of its congener, Stentor coeruleus, a model protist used in cytological and evolutionary studies. Genomes of two congeners, S. coeruleus and S. roeselii, are compared and analyzed, revealing that:(i)the former exhibits a much higher retention rate of colinear-gene pairs(28%) than does S. roeselii, and in S. coeruleus, 75% of genes that have a RBH hit in S. roeselii, have paralogs with high amino-acid identity, consistent with a WGD event in the lineage leading to S. coeruleus;(ii) the S. roeselii genome possesses extremely short intergenic regions, implying that the lengths of intergenic regions are under strong selection;(iii) the unique characteristics of introns may have been shaped in the common ancestor of heterotrichs;(iv) gene families that play a role in activities of multiple protein kinases and voltage-gated ion channels expanded rapidly in the ancestor of both taxa, possibly relating to the remarkable regenerative ability in Stentor. This study offers new insights into the evolutionary dynamics of ciliate genomes,with implications for understanding of the processes underlying the evolution of genomic complexity.

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Rise of β-furanosyl ribonucleosides as the extant RNA component facilitated by simple divalent transition-metal minerals

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Science China Chemistry 2025年

作者： Qianqian Chen Haoxing Xu Bingyue Zhao Yeersen Patehebieke Zerun Zhao xiao Wang School of Chemistry and Chemical Engineering Nanjing University Frontiers Science Center for Critical Earth Material Cycling Nanjing University

The selective nucleoside synthesis through direct condensation between nucleobase and unactivated sugar in aqueous media has long been a formidable obstacle for the early chemical transformations hypothesized to construct the RNAWorld, due to product complexity and the low selectivity of the desired isomer. The preference of β-furanoside, the extant RNA component, has never been documented. Here we report an aqueous ribosylation mediated by divalent transition-metal ions, which unprecedentedly enhances the selectivity of furanosyl ribonucleosides as opposed to the traditionally predominating pyranosyl ones, with the furanoside/pyranoside ratio reaching up to 9/1. Furthermore, β-furanoside stands out for the first time as the most prevalent isomer in the presence of zinc and ammonium salts. The mechanism of this selectivity is elucidated with density functional theory calculations. The selectivity for β-furanoside can be further elevated via the adsorption on a zinc mineral. These findings exhibit as the first example that the selection of nucleosides with the desired, canonical configuration might be completed in the early stage of the RNA-forming process as opposed to later evolution, promoted by simple and widespread transition-metal minerals. The study may also find its value in synthetic chemistry as a guideline for developing a sustainable and selective glycosylation process.

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Development of a general circumferentially nonuniform heat transfer fuel rod model for subchannel analysis and application to helical fuel rods

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Science China Technological Sciences 2025年

作者： Junsen FU Junlong LI xiaowen WANG Qi ZHANG Yao xiao Hanyang GU School of Mechanical Engineering Shanghai Jiao Tong University Key Laboratory of Nuclear Power Systems and Equipment of the Ministry of Education Shanghai Jiao Tong University National Key Laboratory of Nuclear Reactor Technology Nuclear Power Institute of China State Key Laboratory of Nuclear Power Safety Technology and Equipment Shanghai Jiao Tong University

The subchannel analysis method is one of the most crucial transient safety analysis methods in the thermal design of nuclear reactors. The nonuniformity of circumferential heat transfer is slight in conventional pressurized water reactor (PWR)cores, but it is significant in advanced reactors with wire-wrapped or helical fuel rods. Predicting circumferentially nonuniform heat transfer behavior can be challenging owing to the complex geometry of helical fuel rods. In this study, a general circumferentially nonuniform heat transfer fuel rod (GCNF) model is developed to predict the fuel central temperature and circumferential heat flux and wall temperature. This model incorporates a refined two-dimensional fuel conduction model and circumferential nonuniform shape factor, addressing the dual factors contributing to the circumferential nonuniformity of helical fuel rods. An empirical correlation for the nonuniform shape factor is developed based on the computational fluid dynamics (CFD) results, and it is implemented to the subchannel code. The newly developed model is applied to a helical fuel annulus and validated by comparing the prediction results with CFD data. The maximum wall temperature predicted by the code is 1.15°C lower than the value calculated through CFD. In terms of the heat flux, the maximum value at the inner corner is22 kW lower than that obtained from the CFD prediction. The accurate prediction of circumferentially nonuniform heat transfer in helical fuel, concerning the surface heat flux and cladding temperature, addresses existing shortcomings in helical fuel subchannel analysis methods. Additionally, the capability to predict the fuel central temperature is essential for the safety analysis to determine whether fuel rods are melting. The generality of the model framework allows it to be used for the prediction of circumferential nonuniform heat transfer behavior in other types of fuel assemblies.

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Integrating lipidomics and gut microbiota to study the anti-hyperlipidemia effect of Sargentodoxae Caulis extract

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Traditional Medicine Research 2025年第1期10卷 1-11页

作者： xiao-xiao Zhang Li Jia Xiu-Jun Zhan Charity Ngina Qing-Rui Zhang xiao-Ge Li Qi-Bao Jiang Shi Bai Miao-Miao Jiang National Key Laboratory of Chinese Medicine Modernization Tianjin University of Traditional Chinese MedicineTianjin 301617China Haihe Laboratory of Modern Chinese Medicine Tianjin 301617China School of Medicine Taizhou UniversityTaizhou 318000China.

Background:Sargentodoxae Caulis(SC)is the vine stem of Sargentodoxa Cuneata(Oliv.)Rehd.&*** in ***,and it in traditional Chinese medicine has been known for promoting blood circulation and removing blood stasis as recorded in the ancient book“Illustrated Classics of Materia Medica”.It has been used effectively to treat blood stasis too in modern clinical ***,the anti-hyperlipidemia effect of SC is not fully *** paper aims at exploring the use of SC stems to improve the balance of blood lipids in the body,and its new role in treating ***:The effects of SC extract on hyperlipidemia were explored by combining lipidomics and gut ***,we explored the potential mechanism of SC in treating hyperlipidemia by pathway ***:The results showed that the stem extract of SC could restore the physiological and biochemical indices of hyperlipidemia in mice,as well as repair the morphological and structural damage to *** to the Model group,the SC extract significantly reduced the liver index,epididymal fat index,and Lee’s *** also significantly decreased serum levels of total cholesterol,triglycerides,low-density lipoprotein cholesterol,peroxisome proliferator-activated receptor gamma(PPAR-γ),D-lactate,and free fatty acids,while significantly increasing the relative content of peroxisome proliferator-activated receptor alpha(PPAR-α).These changes were statistically ***-targeted lipidomics,based on LC-MS,were utilized to investigate the lipid metabolism characteristics in serum,liver,and epididymal fat of the *** was observed that,compared to the blank group,the Model group exhibited significant changes primarily in glycerol lipids and *** treatment group also displayed alterations in these lipids.A total of 38,81,and 27 differential lipids were identified in serum,liver,and epididymal fat samples,*** these,14 common differenti

关键词： hyperlipidemia Sargentodoxae Caulis lipidomics intestinal flora

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Unlocking the stable interface in aqueous zinc-ion battery with multifunctional xylose-based electrolyte additives

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Journal of Energy Chemistry 2025年第1期100卷 770-778页

作者： xiaoqin Li Jian Xiang Lu Qiu xiaohan Chen Yinkun Zhao Yujue Wang Qu Yue Taotao Gao Wenlong Liu Dan xiao Zhaoyu Jin Panpan Li Institute for Advanced Study Chengdu University School of Mechanical Engineering Chengdu University College of Food and Biological Engineering Chengdu University Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China College of Materials Science and Engineering Sichuan University

The growth of dendrites and the side reactions occurring at the Zn anode pose significant challenges to the commercialization of aqueous Zn-ion batteries（AZIBs）. These challenges arise from the inherent conflict between mass transfer and electrochemical kinetics. In this study, we propose the use of a multifunctional electrolyte additive based on the xylose（Xylo） molecule to address these issues by modulating the solvation structure and electrode/electrolyte interface, thereby stabilizing the Zn anode. The introduction of the additive alters the solvation structure, creating steric hindrance that impedes charge transfer and then reduces electrochemical kinetics. Furthermore, in-situ analyses demonstrate that the reconstructed electrode/electrolyte interface facilitates stable and rapid Zn2+ion migration and suppresses corrosion and hydrogen evolution reactions. As a result, symmetric cells incorporating the Xylo additive exhibit significantly enhanced reversibility during the Zn plating/stripping process, with an impressively long lifespan of up to 1986 h, compared to cells using pure ZnSO4electrolyte. When combined with a polyaniline cathode, the full cells demonstrate improved capacity and long-term cyclic stability. This work offers an effective direction for improving the stability of Zn anode via electrolyte design, as well as highperformance AZIBs.

关键词： Solvation

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Recent Advances in Fibrous Materials for Hydroelectricity Generation

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Nano-Micro Letters 2025年第2期17卷 109-133页

作者： Can Ge Duo Xu xiao Feng Xing Yang Zheheng Song Yuhang Song Jingyu Chen Yingcun Liu Chong Gao Yong Du Zhe Sun Weilin Xu Jian Fang College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123People’s Republic of China National Engineering Laboratory for Modern Silk Soochow UniversitySuzhou 215123People’s Republic of China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200People’s Republic of China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123People’s Republic of China Department of Electrical and Computer Engineering University of MassachusettsAmherstMA 01003USA Department of Materials Imperial College LondonSouth Kensington CampusLondon SW72AZUK College of Textile Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China School of Materials Science and Engineering Shanghai Institute of Technology100 Haiquan RoadShanghai 201418People’s Republic of China

Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable *** generation from ubiquitous and spontaneous phase transitions between liquid and gaseous water has been considered a promising strategy for mitigating the energy *** materials with unique flexibility,processability,multifunctionality,and practicability have been widely applied for fibrous materials-based hydroelectricity generation(FHG).In this review,the power generation mechanisms,design principles,and electricity enhancement factors of FHG are first ***,the fabrication strategies and characteristics of varied constructions including 1D fiber,1D yarn,2D fabric,2D membrane,3D fibrous framework,and 3D fibrous gel are ***,the advanced functions of FHG during water harvesting,proton dissociation,ion separation,and charge accumulation processes are analyzed in ***,the potential applications including power supply,energy storage,electrical sensor,and information expression are also ***,some existing challenges are considered and prospects for future development are sincerely proposed.

关键词： Hydroelectricity Fibrous material Streaming potential Ion diffusion

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压应力条件下缺口产生疲劳裂纹的研究

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金属学报 1984年第5期 341-347页

作者：刘天化褚武扬肖纪美金连强首都钢铁公司设计院北京钢铁学院

对超高强度钢和铝合金的研究表明,在压-压交变载荷下缺口前端能引发疲劳裂纹,其门槛值比拉应力高3—4倍。压应力下缺口裂纹长到一定尺寸（如0.2—0.5mm）后就将停止扩展。如果压应力的最小载荷（绝对值）接近零,则裂纹容易形核（门槛值... 详细信息

对超高强度钢和铝合金的研究表明,在压-压交变载荷下缺口前端能引发疲劳裂纹,其门槛值比拉应力高3—4倍。压应力下缺口裂纹长到一定尺寸（如0.2—0.5mm）后就将停止扩展。如果压应力的最小载荷（绝对值）接近零,则裂纹容易形核（门槛值和拉应力相近）,且能扩展较长的距离。

关键词：缺口门槛值阈值裂纹高倍缺陷(金属) 压应力拉应力张应力

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超声对子宫内膜容受性评价的研究进展

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医学影像学杂志 2018年第8期28卷 1390-1393页

作者：肖继梅撒元红王天琪姜华颖苑丽华孙振高山东中医药大学山东济南250011 山东中医药大学附属医院生殖与遗传中心山东济南250014

随着辅助生殖技术的发展,其成功率备受关注。子宫内膜容受性是提高成功率的关键。但是目前缺乏评价子宫内膜容受性的可靠标准。本文综述了经阴道彩色多普勒(TVCD)从内膜厚度,内膜形态,内膜容积,内膜动脉,血流灌注,内膜运动几个方面对子... 详细信息

随着辅助生殖技术的发展,其成功率备受关注。子宫内膜容受性是提高成功率的关键。但是目前缺乏评价子宫内膜容受性的可靠标准。本文综述了经阴道彩色多普勒(TVCD)从内膜厚度,内膜形态,内膜容积,内膜动脉,血流灌注,内膜运动几个方面对子宫内膜容受性的研究,以期后续临床的研究和应用。

关键词：经阴道彩色多普勒子宫内膜容受性血流灌注

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浅析“女子以肝为先天”在IVF-ET中对高龄女性助孕的指导意义

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辽宁中医杂志 2018年第5期45卷 949-951页

作者：肖继梅孙振高撒元红姜华颖苑丽华王天琪山东中医药大学山东济南250014 山东中医药大学附属医院山东济南250014

中医对辅助生殖技术的指导多从肾论治,少有从肝论治的辨证思想。文章从女子以肝为先天的源流出发,以中医理论为基础,结合高龄女性备孕的常见问题,浅析了从肝论治的指导意义以及临床可用入肝经的方药,为中医药在生殖技术中的应用提供新... 详细信息

中医对辅助生殖技术的指导多从肾论治,少有从肝论治的辨证思想。文章从女子以肝为先天的源流出发,以中医理论为基础,结合高龄女性备孕的常见问题,浅析了从肝论治的指导意义以及临床可用入肝经的方药,为中医药在生殖技术中的应用提供新思路。

关键词：女子以肝为先天高龄助孕意义

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用正电子湮灭技术研究裂纹顶端塑性区内的缺陷分布

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核技术 1982年第6期 38-39页

作者：薛嘉渔季国坤田中卓常香荣吕荣邦肖纪美中国科学院高能物理研究所北京钢铁学院

本文用多普勒加宽谱研究了钢材裂纹顶端塑性区内的应变分布及其充氢后的变化。 40MnNb中强度石油用钢在H2S介质中使用发生氢脆。用这种钢制成10×20×160悬臂梁试样,线切割和疲劳裂纹总长度为5.977mm,经抛光后在悬臂梁上加载,作用于裂... 详细信息

本文用多普勒加宽谱研究了钢材裂纹顶端塑性区内的应变分布及其充氢后的变化。 40MnNb中强度石油用钢在H2S介质中使用发生氢脆。用这种钢制成10×20×160悬臂梁试样,线切割和疲劳裂纹总长度为5.977mm,经抛光后在悬臂梁上加载,作用于裂纹顶端的应力场强度因子KI=273kg/mm3/2,然后加楔固定裂纹顶端的张开位移。在加载的情况下线切割成2×20×40（mm）薄片状恒位移试样,切割面经砂纸磨光,

关键词：塑性区应变分布充氢塑性域裂纹高倍缺陷(金属) 单轴拉伸

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