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Structural variations of a new fertility restorer gene,Rf20,underlie the restoration of wild abortive-type cytoplasmic male sterility in rice

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Molecular Plant 2024年第8期17卷 1272-1288页

作者： Shufeng Song Yixing Li Mudan Qiu na Xu Bin Li Longhui Zhang Lei Li Weijun Chen Jinglei Li Tiankang wa.g Yingxin Qiu Mengmeng gong Dong Yu Hao Dong Siqi Xia Yi Pan Dingyang Yuan Li Li State Key Laboratory of Hybrid Rice Hunan Hybrid Rice Research CenterHunan Academy of Agricultural SciencesChangsha 410125China College of Agronomy Hunan Agricultural UniversityChangsha 410128China College of Plant Protection Hunan Agricultural UniversityChangsha 410128China College of Tropical Crops Hainan UniversityHaikou 570228China Longping Branch College of BiologyHunan UniversityChangsha 410125China

The discovery of a wild abortive-type(wa)cytoplasmic male sterile(CMS)line and breeding its restorer line have led to the commercialization of three-line hybrid rice,contributing considerably to global food ***,the molecular mechanisms underlyingfertility abortion and the restoration of CMs-wa lines remain largely *** this study,we cloned a restorer gene,Rf2o,following a genome-wide association study analysis of the core parent lines of three-line hybrid *** found that Rf20 was present in all core parental lines,but different haplotypes and structural variants of its gene resulted in differences in Rf2o expression levels between sterileand restored ***20 could restorepollen fertility in the CMS-wa line and was found to be responsible for fertility restoration in some CMs lines under high *** addition,we found that Rf20 encodes a pentatricopeptide repeat protein that competes with wa352 for binding with *** interaction enhances Cox11's function as a scavenger of reactive oxygen species,which in turn restores ***,ourstudysuggestsanewactionmodeforpentatricopeptide repeatproteins inthe fertilityrestorationofCMs lines,providing an essential theoretical basisforbreedingrobustrestorer lines and for overcoming high temperature-induced fertility recovery of some CMS lines.

关键词： COX11 cytoplasmic male sterility rf20 wa352 wild abortion

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基于超声透射法的新拌混凝土密度检测研究

佛山陶瓷 2024年第4期34卷 88-90页

作者：娜仁高娃内蒙古交通职业技术学院赤峰024005

混凝土的密度是衡量其质量的一个关键性指标,对工程结构强度和耐久性具有极大的影响。传统的密度检测方法存在一些缺点,如破坏性、时间消耗长等,无法满足实际工程应用需求。超声透射法作为一种非破坏性测试技术,通过分析超声波在混凝土... 详细信息

混凝土的密度是衡量其质量的一个关键性指标,对工程结构强度和耐久性具有极大的影响。传统的密度检测方法存在一些缺点,如破坏性、时间消耗长等,无法满足实际工程应用需求。超声透射法作为一种非破坏性测试技术,通过分析超声波在混凝土中的传播特性和反射信号,可以准确、快速地测量新拌混凝土的密度。该方法具有高精度、无损伤和操作简便的优点,对于提高施工质量控制和实现工程效益具有重要意义。因此,在新拌混凝土密度检测领域中,超声透射法的应用备受关注,并且具有广阔的发展前景。

关键词：超声透射法新拌混凝土密度检测

16MnDR钢焊接接头组织特性及在氢氟酸环境中的腐蚀行为

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机械工程学报 2024年第8期60卷 196-203页

作者：顾玉芬鲁娜石玗孙青岭兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室兰州730050 中核兰州铀浓缩有限公司兰州730060

16MnDR钢中厚板核贫料储罐焊接接头采用脉冲钨极氩弧焊(P-TIg)打底和埋弧焊(SAW)填充及盖面工艺制造。只采用P-TIg焊接的打底层组织为针状铁素体+索氏体,但SAW填充后的打底层发生了组织转变,变为多边形铁素体+蠕虫状屈氏体。通过对焊接... 详细信息

16MnDR钢中厚板核贫料储罐焊接接头采用脉冲钨极氩弧焊(P-TIg)打底和埋弧焊(SAW)填充及盖面工艺制造。只采用P-TIg焊接的打底层组织为针状铁素体+索氏体,但SAW填充后的打底层发生了组织转变,变为多边形铁素体+蠕虫状屈氏体。通过对焊接接头在0.1 M氢氟酸中的浸泡腐蚀试验发现,SAW填充后的打底层的耐蚀性发生严重退化,其原因是蠕虫状屈氏体极细的片层结构在腐蚀溶液中发生了微电偶腐蚀,从而近表面的屈氏体就相当于一个块状的渗碳体,然后与周边多边形铁素体形成的大阴极小阳极的腐蚀电偶加速了铁素体的腐蚀溶解,进而屈氏体失去支撑,最终松动脱落并在宏观上形成了腐蚀坑。这一发现为核贫料储罐的安全服役奠定了理论基础,为后续工艺的优化设计指明了方向。

关键词： 16MnDR钢焊接显微组织热循环腐蚀

Hormone-based pharmacotherapy for metabolic dysfunction-associated fatty liver disease

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Medical Review 2024年第2期4卷 158-168页

作者： Zara Siu wa Chui Yaqian Xue Aimin Xu State Key Laboratory of Pharmaceutical Biotechnology The University of Hong KongHong Kong SARChina Department of Medicine The University of Hong KongHong Kong SARChina School of Biomedical Sciences The University of Hong KongHong Kong SARChina State Key Laboratory of Pharmaceutical Biotechnology The University of Hong Kong999077Hong Kong SARChina Department of Medicine The University of Hong Kong999077Hong Kong SARChina Department of Pharmacology and Pharmacy The University of Hong Kong999077Hong Kong SARChina

Metabolic dysfunction-associated fatty liver disease(MAFLD)has reached epidemic proportions globally in parallel to the rising prevalence of *** its significant burden,there is no approved pharmacotherapy specifically tailored for this *** potential drug candidates for MAFLD have encountered setbacks in clinical trials,due to safety concerns or/and insufficient therapeutic ***,several investigational drugs that mimic the actions of endogenous metabolic hormones,including thyroid hormone receptorβ(THRβ)agonists,fibroblast growth factor 21(FgF21)analogues,and glucagon-like peptide-1 receptor agonists(gLP-1RAs),showed promising therapeutic efficacy and excellent safety *** them,resmetirom,a liver-targeted THRβ-selective agonist,has met the primary outcomes in alleviation of metabolic dysfunction-associated steatohepatitis(MASH),the advanced form of MAFLD,and liver fibrosis in phase-3 clinical *** hormone-based pharmacotherapies not only exhibit varied degrees of therapeutic efficacy in mitigating hepatic steatosis,inflammation and fibrosis,but also improve metabolic ***more,these three hormonal agonists/analogues act in a complementary manner to exert their pharmacological effects,suggesting their combined therapies may yield synergistic therapeutic *** in-depth studies on the intricate interplay among these metabolic hormones are imperative for the development of more efficacious combination therapies,enabling precision management of MAFLD and its associated comorbidities.

关键词： metabolic hormones metabolic dysfunctionassociated steatohepatitis(MASH) liver fibrosis biopharmaceutical development clinical trials

The earliest evidence for a microblade adaptation in the remote,high altitude regions of the Tibetan Plateau

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Science China Earth Sciences 2024年第5期67卷 1561-1573页

作者： Yingshuai JIN Xiaoling ZHANg Shejiang wa.g Junyi gE Wei HE wa DA Yunyao TAN Ziyi YANg Christopher MORgAN Xing gAO Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of SciencesBeijing 100044China University of the Chinese Academy of Sciences Beijing 100049China Cultural Relics Conservation Institute of the Xizang Autonomous Region Lhasa 850000China nagqu Culture and Tourism Bureau Nagqu 852000China University of Nevada Reno 89557USA

Microblade assemblages are among the most common prehistoric archaeological materials found on the Tibetan Plateau(TP)and are thought to indicate large scale migration to and settlement of the *** microblade sites,however,have been systematically excavated,especially in the remotest,highest-elevation regions of the *** timing of the large-scale arrival,spread,and permanent settlement of people on the TP therefore remains *** this paper,we report on a recently excavated site,Locality 3 of the Nwya Devu Site(ND3),located at 4600 meters above sea level(masl),near the shore of Ngoin Lake,on the interior *** analyses reveal a fairly typical microblade technological orientation and two types of microblade cores:wedge-shaped and semi-conical,which are similar to those found throughout North *** Optically Stimulated Luminescence(OSL)dating and AMS^(14)C dating,the age of ND3 ranges from 11 to 10 *** date range indicates ND3 is the oldest microblade site yet recorded in the remote,high-elevation regions of the TP and thus provides important information about when and how hunter-gatherers using microblades began exploiting the higher altitudes of the *** together,studies at ND3 and throughout the TP suggest that a microblade adaptation is associated with the first prolonged human occupation of the plateau and that microblades played a significant role in mediating the risks and facilitating the mobility necessary to permanently inhabit the TP.

关键词： The interior of Tibetan Plateau Nwya Devu locality 3 Microblade Early Holocene High altitude adaption

Strengthening and control of second-phase particle precipitation in ferritic/austenitic/martensitic heat-resistant alloys:a review

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Journal of Iron and Steel Research International 2024年第1期31卷 3-23页

作者： Xue-cheng Peng Han-jie guo Xin-fang Zhang Yi-wa Luo Ye Sun Jing guo Rong-guang Yang Xiao-dan Zheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials University of Science and Technology Beijing(USTB)Beijing100083China Beijing Shougang gitane New MATERIALS Co. Ltd.Beijing102206China

Heat-resistant alloys with excellent mechanical properties are widely used in various fields,and further improvement in their properties is essential to meet the requirements in new-generation advanced supercritical boilers,nuclear reactors,superheaters,and other new materials *** effectively enhance the comprehensive performance of heat-resistant alloys,second-phase particle strengthening has been widely studied,and in the face of different service envi-ronments of advanced heat-resistant steels,the selection of suitable second-phase particles is essential to maximize the performance of these *** this end,three major types of reinforcing phases in heat-resistant alloys such as carbides,rare earth oxides,and intermetallic compounds are summarized.A comparative analysis of the precipitation behavior of the reinforcing phases with different types as well as the risks and means of controlling their use in service,is *** parameters for the application of various types of second-phase particles in heat-resistant alloys are provided to support the design and preparation of new ultrahigh-performance heat-resistant alloys.

关键词： Heat-resistant alloy Second-phase particle Carbide Rare earth oxide Intermetallic compound Strengthening

Deuterium distribution and behavior of blisters in pre-damaged and undamaged tungsten

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Tungsten 2024年第3期6卷 647-656页

作者： Cong Li Xiao-wa wa.g Ran-Ran Su Xuan-Xin Hu Shu-guang Wei Han-Jun Tu Li-Qun Shi Hong-Liang Zhang Key Laboratory of Nuclear Physics and Ion-Beam Application Institute of Modern Physics Fudan University School of Mechanical Engineering Shanghai Jiao Tong University Department of Materials Science and Engineering University of Wisconsin

Tungsten(W),as a plasma-facing material,is subjected to high fluence plasma,resulting in both radiation damage and deuterium(D) *** study explores the blistering behavior and D supersaturated layers in both pre-damaged and undamaged W *** achieve a uniform damage profile similar to neutron irradiation,carbon(C) ions with multiple energies and angles were *** samples were further irradiated with low-energy D ions under two fluences at temperatures from ～380 to 640 *** various experimental techniques,we found that pre-damaged W samples can effectively suppress the formation of blistering and lower the threshold temperature at which the surface remains free of *** also observed the prominent D supersaturated peaks within the depth of 20 nm in both pre-damaged and undamaged ***,a close correlation between blistering and the D supersaturation was *** results suggest that neutron irradiation in the fusion reactors could increase the critical D concentration for blistering,while a greater depth of damage facilitated the inward diffusion of D,thereby reducing the D concentration gradient and alleviating surface blistering.

关键词： Tungsten Deuterium Supersaturated layer Blister Ion irradiation Pre-damage

Supramolecular Manipulation of Intracellular Acidic Vesicles to Improve Cellular Self-Repair and Self-Defense

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CCS Chemistry 2024年第6期6卷 1487-1498页

作者： Ziyi wa.g Chen Sun Yu Dong Yuan-Fu Ding Chen Zhao Ian wa Ho Jiahong Lu Ruibing wa.g State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipaMacao 999078China

Lysosomes are the“cell stomach”that digests various species including macromolecules and pathogens for self-repair and self-defense upon fusion with endosomes,autophagosomes,and ***,artificially manipulating intracellular vesicles could potentially promote lysosome-mediated intracellular digestion for disease prevention and ***,a supramolecular strategy to efficiently tether and fuse acidic vesicles(i.e.,lysosomes,late endosomes,autolysosomes,and phagosomes)has been developed for the first time to enhance the digestion of cellular wastes and foreign matter,including pathogens.A linear polyethylene glycol(PEg)derivative dually tagged with morpholine(MOR)and adamantane(ADA)on the opposite side,namely,MOR-PEg-ADA,was designed to target intracellular acidic vesicles via MOR and to decorate their surfaces with ***,the addition of cucurbit[7]uril(CB[7])grafted hyaluronic acid(HA)induced supramolecular tethering and fusion of acidic vesicles via strong host-guest interactions between CB[7]of CB[7]-HA and ADA residing on the surface of acidic *** a proof-ofconcept,the overall cellular metabolism,including endogenous autophagy and the exogenous endocytosis and phagocytosis,was effectively upregulated,demonstrating that supramolecular regulation of the dynamics of intracellular acidic vesicles may promote the lysosome’s digestion to significantly improve cellular self-repair and self-defense.

关键词： supramolecular chemistry organelle regulation intracellular acidic vesicles lysosomes selfdefense self-repair

Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

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Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： gürel Cam Ali günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200 Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(wa-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(waAM) 3-D printing High deposition rate