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Journal of Materials Science & Technology 2022年第10期105卷 203-213页

作者： yutong shi Weiyan Lu Wenhai Sun Suode Zhang Baijun Yang Jianqiang Wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Gas atomization is now an important production technique for Fe-based amorphous alloy powders used in additive manufacturing,particularly selective laser melting,fabricating large-sized Fe-based bulk metallic glasses.Using the realizable k-εmodel and discrete phase model theory,the flow dynamics of the gas phase and gas-melt two-phase flow felds in the close-wake condition were investigated to establish the correlation between high gas pressure and powder particle characteristics.The locations of the recirculation zones and the shapes of Mach disks were analyzed in detail for the type of discrete-jet closed-coupled gas atomization nozzle.In the gas-phase flow feld,the vortexes,closed to the Mach disk,are found to be a new deceleration method.In the two-phase flow feld,the shape of Mach disk changes from“S”-shape to“Z”-shape under the impact of the droplet flow.As predicted by the wave model,with the elevation of gas pressure,the size of the particle is found to gradually decrease and its distribution becomes more concentrated.Simulation results were compliant with the Fe-based amorphous alloy powder preparation tests.This study deepens the understanding of the gas pressure impacting particle features via gas atomization,and contributes to technological applications.

关键词： Gas atomization Fe-based amorphous powder Closed-wake Gas-melt flow Break-up Particle size distribution

Phase Evolution and Glass Formation in an Fe-Based Alloy

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金属学报:英文版 2023年第9期36卷 1502-1510页

作者： Ping Huang yutong shi Wei Zhang Suode Zhang Yinglei Ren Keqiang Qiu Jianqiang Wang School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China Shenyang National Laboratory for Materials Science Institute of Metal ResearchCASShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

The understanding of phase competing is of pretty importance in designing high glass-forming systems. In this work, it has been investigated experimentally and theoretically the phase evolution and glass formation of a wedge-casting Fe-based alloy. The results indicated that the phase formation was sensitive to the wedge position, i.e., there were amorphous phase, Fe_(2)P, {Fe, Ni} and α-Fe precipitates as well as M_(23)B_(6) phase at the distances of 3, 10 and 20 mm away from the wedge-tip, respectively. These were closely connected with the variation of cooling rate, embodied in the heat transfer at the solidification process. Furthermore, we constructed the time–temperature-transformation (TTT) diagrams of the iron-based alloy and these crystal phases through calculating Rc-related functions. Finally, the glass-forming features of the wedge-shaped Fe-based alloy have been elucidated in accordance with a crystallization kinetics analysis of the recorded temperature data and the phase selection competition. This research provides us an insight into in-depth understanding bulk metallic glass from the perspective of kinetics competition of crystallization phases.

关键词： Bulk metallic glass Phase evolution Crystallization kinetics Cooling rate

JAG1 enhances angiogenesis in triple-negative breast cancer through promoting the secretion of exosomal lncRNA MALAT1

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Genes & Diseases 2023年第5期10卷 2167-2178页

作者： Junping Liu yutong shi Minmin Wu Fengmei Zhang Mengqi Xu Zhiqiang He Min Tang Key Laboratory of Laboratory Medical Diagnostics Designated by the Chinese Ministry of Education Chongqing Medical UniversityChongqing 400016China

Despite significant improvements in five-year survival rates due to early diagnosis and combination therapy, triple-negative breast cancer (TNBC) treatment remains a major challenge. Finding new and effective targets for diagnosis and drug therapy is urgent for TNBC patients. Jagged-1 (JAG1), one of the canonical ligands of the Notch signaling pathway, is involved in vascular budding and is a poor prognostic factor of TNBC. In this study, combined with quantitative real-time PCR, database analysis, animal experiments, and other means, JAG1 was confirmed to be related to the poor prognosis of TNBC patients. JAG1 was highly expressed in MDA-MB-231 Bone (231B) cells, with stronger invasion and metastasis ability than MDA-MB-231 (231) cells. Treatment of human vascular endothelial cells (HUVEC) with TNBC conditioned medium showed that TNBC JAG1 promoted the angiogenesis of HUVEC. Next, we detected the exosomes extracted from TNBC conditioned medium and found that JAG1 promoted the exosome secretion from 231 cells via ALIX-RAB11A/RAB35. In addition, we also found that the exosomes from JAG1 overexpressed TNBC cells contained more long non-coding RNA (lncRNA) MALAT1 , and MALAT1 promoted angiogenesis of HUVEC by targeting miR-140-5p . Finally, the angiogenesis-promoting effect of JAG1 in TNBC was further investigated by matrix gel assay. In conclusion, we reveal that JAG1 has a pro-invasion effect on TNBC and is involved in microenvironment angiogenesis by promoting exosome secretion and the MALAT1-miR-140-5p-JAG1/VEGFA pathway.

关键词： Angiogenesis Exosome JAG1 lncRNAMALAT1 Triple-negative breast cancer

Herbicide 2,4-dichlorophenoxyacetic acid interferes with MAP kinase signaling in Fusarium graminearum and is inhibitory to fungal growth and pathogenesis

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Stress Biology 2023年第1期3卷 345-361页

作者： Kaili Duan Qifang Shen Yu Wang Ping Xiang yutong shi Chenfei Yang Cong Jiang Guanghui Wang Jin-Rong Xu Xue Zhang State Key Laboratory of Crop Stress Biology for Arid Areas College of Plant ProtectionNorthwest A&F UniversityYangling 712100ShaanxiChina Department of Botany and Plant Pathology Purdue UniversityWest LafayetteIN 47907USA

Plant hormones are important for regulating growth,development,and plant-pathogen interactions.Some of them are inhibitory to growth of fungal pathogens but the underlying mechanism is not clear.In this study,we found that hyphal growth of Fusarium graminearum was significantly reduced by high concentrations of IAA and its metabolically stable analogue 2,4-dichlorophenoxyacetic acid(2,4-D).Besides inhibitory effects on growth rate,treatments with 2,4-D also caused significant reduction in conidiation,conidium germination,and germ tube growth.Treatments with 2,4-D had no obvious effect on sexual reproduction but significantly reduced TRI gene expression,toxisome formation,and DON production.More importantly,treatments with 2,4-D were inhibitory to infection structure formation and pathogenesis at concentrations higher than 100μM.The presence of 1000μM 2,4-D almost completely inhibited plant infection and invasive growth.In F.graminearum,2,4-D induced ROS accumulation and FgHog1 activation but reduced the phosphorylation level of Gpmk1 MAP kinase.Metabolomics analysis showed that the accumulation of a number of metabolites such as glycerol and arabitol was increased by 2,4-D treatment in the wild type but not in the Fghog1 mutant.Transformants expressing the dominant active FgPBS2^(S451D T455D) allele were less sensitive to 2,4-D and had elevated levels of intracellular glycerol and arabitol induced by 2,4-D in PH-1.Taken together,our results showed that treatments with 2,4-D interfere with two important MAP kinase pathways and are inhibitory to hyphal growth,DON biosynthesis,and plant infection in F.graminearum.

关键词： Fungal pathogenesis MAP kinase pathways 2,4-D,Fusarium graminearum

Effect of Sr on Grain Refinement of Mg–3%Al Alloy Containing Trace Fe by Carbon-Inoculation

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Journal of Materials Science & Technology 2016年第12期32卷 1297-1302页

作者： Jun Du yutong shi Mingchuan Zhou Wenfang Li School of Materials Science and Engineering South China University of Technology

Magnesium（Mg）-3% aluminum（Al）（in weight） alloy was modified by carbon（C） inoculation combining with strontium（Sr）.The effects of trace 0.1% iron（Fe） addition and operating sequence of carboninoculation and Fe addition on the grain size of Mg-3%Al alloy were studied.The results reveal that the Sr addition could effectively suppress grain-coarsening resulted from the inclusion of Fe in the carboninoculated Mg-Al alloy.Sr addition could contribute to the formation of the duplex-phase particles that Al-C-rich phases coated on Al-Fe or Al-C-Fe-rich phases,regardless of the Fe addition sequence.These duplex-phase particles should be the potent substrates for α-Mg grains.Consequently,Sr addition could effectively subsidize the inhibiting effect of Fe on grain refinement and the active nuclei were maintained.In other words,Sr plays a counter role in the poisoning effect of Fe on the microstructure of Mg-3%Al alloy.

关键词： Magnesium alloy Grain refinement Carbon-inoculation Nucleating substrate Poisoning-free

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火星峡谷网研究的现状、问题与展望

地球科学 2024年第1期49卷 359-374页

作者：史语桐杨勇赵健楠黄俊肖龙中国地质大学地球科学学院行星科学研究所湖北武汉430074

广泛分布于火星表面的谷网地貌作为火星地质环境演变的记录者,对认识火星地质历史时期的环境变化、了解火星古气候与宜居性具有重要意义.随着中国火星探测计划的开展,详细了解火星谷网的研究进展尤为重要.对火星谷网地貌的探测历史、形... 详细信息

广泛分布于火星表面的谷网地貌作为火星地质环境演变的记录者,对认识火星地质历史时期的环境变化、了解火星古气候与宜居性具有重要意义.随着中国火星探测计划的开展,详细了解火星谷网的研究进展尤为重要.对火星谷网地貌的探测历史、形貌分类、时空分布、成因假说等方面的研究进展进行了总结,在此基础上提出了当前火星谷网研究中存在的主要问题与争议,并认为未来可着重在谷网侵蚀沉积物的识别分析、谷网对古气候重建所提供的地质学证据与理论模型预测结果的协调、以及火星与地球谷网的类比等方面开展研究.

关键词：火星峡谷网水源古气候流水活动行星地质

重度牙周炎磨牙拔牙同期微翻瓣牙槽嵴保存术后种植修复效果的前瞻性队列研究

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中华口腔医学杂志 2024年第4期59卷 318-325页

作者：危伊萍徐涛胡文杰刘云松石宇彤北京大学口腔医学院·口腔医院牙周科、国家口腔医学中心、国家口腔疾病临床医学研究中心、口腔生物材料和数字诊疗装备国家工程研究中心、口腔数字医学北京市重点实验室北京100081 北京大学口腔医学院·口腔医院急诊科、国家口腔医学中心、国家口腔疾病临床医学研究中心、口腔生物材料和数字诊疗装备国家工程研究中心、口腔数字医学北京市重点实验室北京100081 北京大学口腔医学院·口腔医院修复科、国家口腔医学中心、国家口腔疾病临床医学研究中心、口腔生物材料和数字诊疗装备国家工程研究中心、口腔数字医学北京市重点实验室北京100081 北京大学国际医院口腔科北京102206

目的评价重度牙周炎磨牙拔牙微翻瓣牙槽嵴保存与自然愈合后实施种植修复3年种植体存留率、成功率、种植体周软组织情况以及边缘骨水平变化。方法纳入2015年3月至2017年1月就诊于北京大学口腔医学院·口腔医院牙周科,因重度牙周病变需要... 详细信息

目的评价重度牙周炎磨牙拔牙微翻瓣牙槽嵴保存与自然愈合后实施种植修复3年种植体存留率、成功率、种植体周软组织情况以及边缘骨水平变化。方法纳入2015年3月至2017年1月就诊于北京大学口腔医学院·口腔医院牙周科,因重度牙周病变需要拔除磨牙并拟进行种植修复的40例重度牙周炎患者,共计40颗磨牙,根据就诊时间,前20颗磨牙纳入自然愈合组,后20颗磨牙纳入微翻瓣牙槽嵴保存组,两组患者分别在拔牙后自然愈合或经过微翻瓣牙槽嵴保存后进行种植治疗,6个月后两组患者均接受上部结构修复。所有患者在种植冠修复完成2周内(基线)、修复后1、2、3年复查记录种植体改良菌斑指数、探诊深度、改良出血指数和颊侧角化组织宽度;拍摄平行投照根尖片,测量种植体边缘骨水平,计算边缘骨丧失量。采用独立样本t检验或Mann-Whitney U检验比较两组间上述临床指标和影像学指标的差异。结果两组种植体负重后3年存留率和成功率均为100%(20/20)。两组种植体改良菌斑指数、探诊深度、改良出血指数、颊侧角化组织宽度和边缘骨丧失在修复后1、2、3年差异均无统计学意义(均P>0.05)。自然愈合组负重3年时边缘骨丧失为0.22(0.14,0.34)mm,微翻瓣牙槽嵴保存组负重3年时边缘骨丧失为0.21(0.12,0.30)mm。结论在本临床研究有限的范围内,重度牙周炎磨牙拔牙微翻瓣牙槽嵴保存和自然愈合种植修复后3年种植体的临床效果相当。

关键词：牙周炎磨牙拔牙牙槽嵴保存牙种植

火星资源赋存状况及其原位利用技术研究进展与展望

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地质学报 2024年第2期98卷 611-622页

作者：赵健楠张诗琪耿志卿肖龙王江史语桐陆希中国地质大学(武汉)地质探测与评估教育部重点实验室湖北武汉430074 中国地质大学(武汉)地球科学学院行星科学研究所湖北武汉430074 上海卫星工程研究所上海200240 上海市深空探测技术重点实验室上海200240

太空资源的勘探及利用是深空探测的重要目的之一。火星是人类最容易到达和资源利用最为迫切的行星,对火星资源进行勘查和原位利用是未来火星载人探测及基地建设需要解决的重要问题。本文对火星大气资源、水资源、土壤与岩石矿物资源、... 详细信息

太空资源的勘探及利用是深空探测的重要目的之一。火星是人类最容易到达和资源利用最为迫切的行星,对火星资源进行勘查和原位利用是未来火星载人探测及基地建设需要解决的重要问题。本文对火星大气资源、水资源、土壤与岩石矿物资源、风能与太阳能资源等可利用资源的类型及赋存状况进行了分析,制作了火星资源的全球分布图,并从资源分布的角度提出了未来火星资源探测及火星基地建设的首选区域。同时,本文也总结了火星原位资源利用技术的研究进展及问题,认为未来需要从以下几个方面开展进一步研究:加强火星资源的针对性勘查与评估;开发新的资源利用模式与技术;建立资源利用成本的综合评估模型;完善资源开发与利用相关的法律法规。

关键词：火星太空资源原位资源利用火星基地建设备选着陆区

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磁共振成像在颅内肿瘤周围脑区中的研究进展

磁共振成像 2024年第6期15卷 172-178页

作者：赵恩东施禹彤宋雪琳娄诗云杨超大连医科大学附属第一医院放射科大连116000 大连医科大学附属第二医院放射科大连116000 大连大学附属新华医院神经内科大连116000

肿瘤并不是单一生长的组织,其周围特异性的肿瘤微环境与其发展息息相关,肿瘤周围脑区是指肿瘤原发病灶周围邻近的大脑区域,在放射学上通常包括瘤周脑实质及瘤周水肿区域。充分认识并挖掘肿瘤及瘤周脑区的潜在放射学信息,将在肿瘤的科学... 详细信息

肿瘤并不是单一生长的组织,其周围特异性的肿瘤微环境与其发展息息相关,肿瘤周围脑区是指肿瘤原发病灶周围邻近的大脑区域,在放射学上通常包括瘤周脑实质及瘤周水肿区域。充分认识并挖掘肿瘤及瘤周脑区的潜在放射学信息,将在肿瘤的科学研究及临床诊疗中获益。本文阐明了瘤周脑区的定义与形成机制,并对基于磁共振成像的各项技术,包括扩散成像、灌注成像、磁共振波谱成像、酰胺质子转移加权成像及影像组学,在颅内肿瘤周围脑区中的应用进展进行综述,旨在通过开展瘤周脑区的影像学研究继而为颅内肿瘤的鉴别诊断、基因分子分型、探寻术中切除范围、预测预后及监测疗效等方面提供新思路。

关键词：脑肿瘤瘤周脑区磁共振成像影像组学多模态

氮缺乏对84K杨树组培苗光合特性及次生代谢的影响

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西部林业科学 2024年第3期53卷 161-168页

作者：苗娜史羽桐王胜芳高媛王慧梅青岛工程职业学院海洋财经学院山东青岛266000 东北林业大学化学化工与资源利用学院黑龙江哈尔滨150040 浙江农林大学林业与生物技术学院亚热带森林培育国家重点实验室浙江杭州311300

研究氮缺乏对84K杨树组培苗生长的影响,以期为84K杨的育种与繁殖提供理论基础。以84K杨树组培苗为实验材料,通过氮缺乏处理,测定84K杨树组培苗的生物量、光合参数、叶绿素荧光参数,并进一步分析氮缺乏时全氮、全碳、碳氮比、总酚及抗氧... 详细信息

研究氮缺乏对84K杨树组培苗生长的影响,以期为84K杨的育种与繁殖提供理论基础。以84K杨树组培苗为实验材料,通过氮缺乏处理,测定84K杨树组培苗的生物量、光合参数、叶绿素荧光参数,并进一步分析氮缺乏时全氮、全碳、碳氮比、总酚及抗氧化活性的变化。结果显示:随着培养基中氮含量的减少,84K杨树组培苗的干重、净光合速率(P n)和气孔导度(G s)均受到抑制,同时,氮缺乏导致84K杨树组培苗叶绿素a、叶绿素b、总叶绿素含量及最大光化学效率(Fv/Fm)降低。此外,随着培养基中氮素的减少,84K杨树组培苗中全氮含量显著减少,碳氮比显著升高,总酚含量显著增加。抗氧化分析结果表明,培养基中氮含量越低,组培苗的抗氧化活性越好。相关性分析表明,生物量与光合参数及叶绿素含量之间存在极显著正相关,但与总酚含量之间存在负相关;全氮含量与总酚含量之间存在负相关,与全碳及碳氮比之间存在正相关;同时84K杨树组培苗总酚含量及抗氧化活性之间具有明显的相关性。研究结果表明:氮缺乏可对84K杨树组培苗的光合生理及次生代谢产物产生影响,不利于84K杨树组培苗的生长和光合作用,但促进了多酚等抗氧化物质的产生。本研究可为84K杨树的栽培管理提供理论依据和基础数据。

关键词：氮缺乏 84K杨树组培苗生长光合总酚抗氧化活性

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