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Lactate and lactylation in breast cancer:current understanding and therapeutic opportunities
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作者 Lan Huang xuemei chen +2 位作者 Meina Yan Ze Xiang Jian Wu 《Cancer Biology & Medicine》 2025年第7期789-805,共17页
Breast cancer(BC)has the highest prevalence among cancers specific to women,and its incidence rates are increasing in many countries.Subtypes of BC,including HER2-positive or triple-negative BC,exhibit differing treat... Breast cancer(BC)has the highest prevalence among cancers specific to women,and its incidence rates are increasing in many countries.Subtypes of BC,including HER2-positive or triple-negative BC,exhibit differing treatment responses;consequently,demand for personalized therapy is increasing,and relevant precision medicine strategies are under development.Aerobic glycolysis in cancer cells can lead to excessive lactate production,which in turn promotes lactylation and influences tumor cell behavior.Epigenetic alterations and metabolic reprogramming are prominent characteristics of tumors.Because lactate and lactylation are important in cancer,further investigation of the mechanisms underlying lactate metabolism and lactylation,and the development of therapeutic strategies targeting these processes,are topics of increasing interest.This review describes current research on lactate metabolism and lactylation in BC,thus offering new perspectives for advancing treatment and management toward more precise and personalized approaches that will ultimately increase BC survival rates and patient quality of life. 展开更多
关键词 LACTATE lactylation breast cancer tumor metabolism immunotherapy prognosis
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基于Tei指数评价蒽环类药物对急性白血病患儿心脏毒性的研究 被引量:1
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作者 陈雪梅 郭品 +3 位作者 钏刘芳 王梓 李雪娇 何文姬 《昆明医科大学学报》 CAS 2024年第2期117-122,共6页
目的应用超声技术监测急性白血病患儿使用蒽环类药物后的心功能,以期得到心功能早期变化的指标。方法按照入组与排除标准选取2018年3月至2020年12月昆明医科大学附属儿童医院白血病患儿,记录其常规心脏超声指标和组织多普勒,并应用TeiS... 目的应用超声技术监测急性白血病患儿使用蒽环类药物后的心功能,以期得到心功能早期变化的指标。方法按照入组与排除标准选取2018年3月至2020年12月昆明医科大学附属儿童医院白血病患儿,记录其常规心脏超声指标和组织多普勒,并应用TeiS、TeiRL、TeiM和TeiT评估心脏收缩功能的变化。结果正常组和用药前实验组常规心脏超声指标中LVEF的均值都在60%以上,FS、SV及EDV均在正常范围,常规指标、TDI和Tei指数无统计学意义(P>0.05);实验组累积剂量为200和250 mg/m^(2)组的TeiM与用药前存在显著差异(P<0.05);200和250 mg/m^(2)组与用药前的TeiRL存在显著差异(P<0.05);200和250 mg/m^(2)组与用药前的TeiT存在显著差异(P<0.05)。结论Tei指数可作为白血病患儿应用蒽环类药物后左右心功能的早期改变较敏感监测指标。 展开更多
关键词 蒽环类药物 心脏毒性 超声心动图 室间隔基底段心肌做功指数 右室侧壁基底心肌做功指数 左心心肌做功指数
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基于宏基因组分析纳帕海高原湿地微生物及其碳氮代谢多样性 被引量:10
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作者 徐志伟 陈学梅 +2 位作者 魏云林 张琦 季秀玲 《生物工程学报》 CAS CSCD 北大核心 2021年第9期3276-3292,共17页
由于地理位置特殊和生态系统类型的复杂多样性,高原湿地在水源供给、温室气体调节、生物多样性保护等方面具有不可忽视的生态作用。纳帕海高原湿地是特殊的低纬度高海拔湿地类型,目前关于其微生物多样性的研究较少。文中基于宏基因组学... 由于地理位置特殊和生态系统类型的复杂多样性,高原湿地在水源供给、温室气体调节、生物多样性保护等方面具有不可忽视的生态作用。纳帕海高原湿地是特殊的低纬度高海拔湿地类型,目前关于其微生物多样性的研究较少。文中基于宏基因组学方法对纳帕海高原湿地微生物的基因组进行测序,在细菌域中鉴定出184个门、3 262个属、24 260个种;在古菌域中检测到13个门、32个属;在真菌域中共有13个门、47个属。土壤和水体的物种多样性具有明显差异:在门水平上,土壤中酸杆菌门、变形菌门和放线菌门为优势菌门,水体则以变形菌门和拟杆菌门为主。通过宏基因组分析获得纳帕海微生物群落的多样性数据,并对高原湿地中固碳途径和氮代谢途径进行了初步分析。研究表明碳、氮代谢基因丰度较高,湿地微生物固碳途径主要以卡尔文循环、还原性三羧酸循环和3-羟基丙酸循环为主,变形菌门、绿弯菌门、泉古菌门为主要固碳菌群;对于氮循环,水中以固氮和异化硝酸盐还原过程为主,土壤则以硝化和反硝化过程为主,变形菌门、硝化螺旋菌门、疣微菌门、放线菌门、奇古菌门和广古菌门的微生物为氮循环的主要贡献者。本研究揭示的纳帕海高原湿地微生物多样性,为湿地环境的综合治理和保护提供了新的知识。 展开更多
关键词 纳帕海高原湿地 微生物群落 宏基因组学 碳氮代谢 生物多样性
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前噬菌体研究进展 被引量:10
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作者 陈学梅 魏云林 季秀玲 《遗传》 CAS CSCD 北大核心 2021年第3期240-248,共9页
噬菌体是地球上最多的生物实体,一直被认为是细菌的天敌。然而随着基因组学和分子生物学等技术的快速发展,人们发现噬菌体与宿主之间存在微妙而复杂的关系。前噬菌体是指溶原性细菌内存在的整套噬菌体DNA基因组,广泛分布在细菌基因组中... 噬菌体是地球上最多的生物实体,一直被认为是细菌的天敌。然而随着基因组学和分子生物学等技术的快速发展,人们发现噬菌体与宿主之间存在微妙而复杂的关系。前噬菌体是指溶原性细菌内存在的整套噬菌体DNA基因组,广泛分布在细菌基因组中,对调节细菌宿主生理具有重要作用,如参与调节宿主的毒力、影响生物膜形成、赋予宿主免疫力等。有趣的是,前噬菌体可以通过“监听”细菌的群体感应来调节自身的溶原–裂解状态。近年来,一些细菌中由前噬菌体编码的抗CRISPR蛋白的发现引起了人们对前噬菌体研究的关注。因此,对前噬菌体的研究可以为改造宿主和前噬菌体提供基础理论参考。本文对前噬菌体的预测、分布、分类及功能进行了综述,以期为进一步研究噬菌体与宿主间的关系提供基础。 展开更多
关键词 前噬菌体 毒力 抗CRISPR蛋白 溶原转换 群体感应
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LincRNA AC027700.1在小鼠蜕膜化中的表达研究 被引量:2
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作者 谭丽萍 高茹菲 +4 位作者 尹鑫 陈雪梅 李方方 袁柳 何俊琳 《遗传》 CAS CSCD 北大核心 2022年第2期168-177,共10页
长链非编码RNA(long non-coding RNA,lncRNA)是一类长度大于200 nt、不具有蛋白编码潜能的RNA分子。在细胞生长发育、物质代谢以及疾病等的发生发展过程中起关键调控作用,但在蜕膜化相关领域研究报道较少。为了探究lincRNA AC027700.1... 长链非编码RNA(long non-coding RNA,lncRNA)是一类长度大于200 nt、不具有蛋白编码潜能的RNA分子。在细胞生长发育、物质代谢以及疾病等的发生发展过程中起关键调控作用,但在蜕膜化相关领域研究报道较少。为了探究lincRNA AC027700.1在早孕小鼠子宫内膜中的表达规律,初步探讨AC027700.1在小鼠蜕膜化中的作用,本研究利用qRT-PCR检测AC027700.1在小鼠孕第6 d胚胎着床点及着床旁子宫组织中的表达;构建了假孕小鼠体内人工诱导蜕膜化模型和原代小鼠子宫内膜基质细胞体外诱导蜕膜化模型,qRT-PCR检测AC027700.1在人工诱导蜕膜化的组织和细胞中的表达;通过分离细胞核、细胞质RNA,qRT-PCR检测AC027700.1在胞核和胞质中的相对表达水平;利用GOseq和KOBAS软件对AC027700.1下游靶基因进行GO和KEGG分析。结果表明,AC027700.1在小鼠孕第6 d着床点子宫组织中的表达显著高于着床旁;AC027700.1在成功诱导蜕膜化的子宫内膜组织及细胞中的表达显著高于未诱导的组织及细胞;AC027700.1主要定位于细胞核内;AC027700.1下游靶基因主要富集于自噬通路、细胞周期以及RNA转运等通路。本研究初步揭示了lincRNA AC027700.1可能与早孕子宫内膜蜕膜化有关,但具体作用及调节机制还有待进一步研究。 展开更多
关键词 lincRNA AC027700.1 蜕膜化 子宫内膜 着床
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Buyang Huanwu Decoction regulates neural stem cell behavior in ischemic brain 被引量:18
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作者 Baiyan Liu Guangxian Cai +1 位作者 Jian Yi xuemei chen 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第25期2336-2342,共7页
The traditional Chinese medicine Buyang Huanwu Decoction has been shown to improve the neu- rological function of patients with stroke. However, the precise mechanisms underlying its effect remain poorly understood. I... The traditional Chinese medicine Buyang Huanwu Decoction has been shown to improve the neu- rological function of patients with stroke. However, the precise mechanisms underlying its effect remain poorly understood. In this study, we established a rat model of cerebral ischemia by middle cerebral artery occlusion and intragastrically administered 5 g/kg Buyang Huanwu Decoction, once per day, for 1, 7, 14 and 28 days after cerebral ischemia. Immunohistochemical staining revealed a number of cells positive for the neural stem cell marker nestin in the cerebral cortex, the subven- tricular zone and the ipsilateral hippocampal dentate gyrus in rat models of cerebral ischemia. Buyang Huanwu Decoction significantly increased the number of cells positive for 5-bromodeoxyuridine (BrdU), a cell proliferation-related marker, microtubule-associated protein-2, a marker of neuronal differentiation, and growth-associated protein 43, a marker of synaptic plasticity in the ischemic rat cerebral regions. The number of positive cells peaked at 14 and 28 days after intragastric administration of Buyang Huanwu Decoction. These findings suggest that Buyang Huanwu Decoction can promote the proliferation and differentiation of neural stem cells and en- hance synaptic plasticity in ischemic rat brain tissue. 展开更多
关键词 neural regeneration traditional Chinese medicine Buyang Huanwu Decoction cerebral ischemia NESTIN BRDU microtubule-associated protein-2 growth-associated protein 43 neural stem cells proliferation differentiation cerebral cortex subventricular zone dentate gyrus grants-supportedpaper NEUROREGENERATION
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Evolution of permafrost in Northeast Chinasince the Late Pleistocene 被引量:7
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作者 HuiJun Jin XiaoLi Chang +6 位作者 DongLiang Luo RuiXia He LanZhi Lu SiZhong Yang DongXin Guo xuemei chen Stuart A.Harris 《Research in Cold and Arid Regions》 CSCD 2016年第4期269-296,共28页
In Northeast China, permafrost advanced and retreated several times under the influences of fluctuating paleo-climatesand paleo-environments since the Late Pleistocene. During the last 60 years, many new data were obt... In Northeast China, permafrost advanced and retreated several times under the influences of fluctuating paleo-climatesand paleo-environments since the Late Pleistocene. During the last 60 years, many new data were obtained and studies wereconducted on the evolution of permafrost in Northeast China, but so far no systematic summary and review have been made.Based on sedimentary sequences, remains of past permafrost, paleo-flora and -fauna records, and dating data, permafrostevolution since the Late Pleistocene has been analyzed and reconstructed in this paper. Paleo-temperatures reconstructedfrom the remains of past permafrost and those from paleo-flora and -fauna are compared, and thus the southern limitof permafrost (SLP) in each climate period is inferred by the relationship of the permafrost distribution and the meanannual air/ground temperatures (MAAT/MAGT). Thus, the evolutionary history of permafrost is here divided into fivestages: (1) the Late Pleistocene (Last Glaciation, or LG) (65 to 10–8.5 ka), the Last Glaciation Maximum (LGM, 21–13 ka)in particular, the coldest period in the latest history with a cooling of about 6~10 °C, characterized by extensive occurrencesof glaciation, flourishing Mammathas-Coelodonta Faunal Complex (MCFC), widespread aeolian deposits, and significantsea level lowering, and permafrost greatly expanded southwards almost to the coastal plains (37°N–41°N); (2) the HoloceneMegathermal Period (HMP, 8.5–7.0 to 4.0–3.0 ka), 3~5 °C warmer than today, permafrost retreated to about 52°N; (3) theLate Holocene Cold Period (Neoglaciation) (4.0–3.0 to 1.0–0.5 ka), a cooling of 1~3 °C, some earlier thawed permafrost wasrefrozen or attached, and the SLP invaded southwards to 46°N; (4) the Little Ice Age (LIA, 500 to 100–150 a), the latestcold period with significant permafrost expansion; and (5) climate warming since the last century, during which NortheastChina has undergone extensive permafrost degradation. The frequent and substantial expansions and retreats of permafrosthave greatly impacted cold-region environments in Northeast China. North of the SLP during the HMP, or in the presentcontinuous permafrost zone, the existing permafrost was largely formed during the LG and was later overlapped by thepermafrost formed in the Neoglaciation. To the south, it was formed in the Neoglaciation. However, many aspects ofpermafrost evolution still await further investigations, such as data integration, numerical reconstruction, and merging ofChinese permafrost history with those of bordering regions as well as collaboration with related disciplines. Of these, studies on the evolution and degradation of permafrost during the past 150 years and its hydrological, ecological, and environmentalimpacts should be prioritized. 展开更多
关键词 Last Glaciation (LG) Holocene Megathermal Period (HMP) Neoglaciation Little Ice Age (LIA) NortheastChina permafrost evolution
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Hydrophilic carbon nanotube membrane enhanced interfacial evaporation for desalination 被引量:5
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作者 Yaqi Hou Qianxiao Wang +3 位作者 Shuli Wang Miao Wang xuemei chen Xu Hou 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第4期2155-2158,共4页
Carbon nanotube-based(CNT-based) interfacial evaporation material is one of the most potential materials for solar desalination. Here, we studied the evaporation rate of the CNT-based membranes with different hydrophi... Carbon nanotube-based(CNT-based) interfacial evaporation material is one of the most potential materials for solar desalination. Here, we studied the evaporation rate of the CNT-based membranes with different hydrophilic and hydrophobic chemical modified surfaces using molecular dynamic simulations.We found that the hydrogen bonding density among water molecules at the interface is a key factor in enhancing the evaporation rate. For a hydrophilic CNT-based membrane, the strong interactions between the membrane outer surface and the water molecules can destroy the water-water hydrogen bonding interactions at the interface, resulting in the reduction of the hydrogen bonding density, leading to an enhancement effect in evaporation rate. We also found that there is an optimal thickness for evaporation membrane. These findings could provide some theoretical guidance for designing and exploring advanced CNT-based systems with more beneficial performance in water desalination. 展开更多
关键词 Hydrophilic surface chemistry Carbon nanotube Water evaporation DESALINATION Molecular dynamic simulation
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Construction and analysis of a plant transformation binary vector pBDGG harboring a bi-directional promoter fusing dual visible reporter genes 被引量:4
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作者 Chunxiao Zhang Ying Gai +3 位作者 Wenqi Wang Yanyan Zhu xuemei chen Xiangning Jiang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第4期245-249,共5页
The constitutive promoter of cauliflower mosaic virus 35S (CaMV 35S) is a polar unidirectional promoter and is widely used in plant genetic engineering. In the present study, the unidirectional CaMV 35S promoter has... The constitutive promoter of cauliflower mosaic virus 35S (CaMV 35S) is a polar unidirectional promoter and is widely used in plant genetic engineering. In the present study, the unidirectional CaMV 35S promoter has been modified to a bi-directional promoter by fusing its minimal promoter element to the 5' end of CaMV 35S promoter in the opposite orientation. To qualitatively and quantitatively estimate its bi-directional transcriptional function and activity, two visible reporter genes, gusA (13-glucuronidase, GUS) and gfp (green fluorescent protein, GFP), were fused to the two ends of the promoter in bi-orientations ending with NOS terminator sequences, respectively. Stable expression of gusA and gfp genes in transgenic tobacco (Nicotiana tabacum L.) was visulized by histochemically staining for GUS and fluorescence microscopic observation under UV for GFP in transgenic plants. The expression of two reporter genes showed that the constructed bi-directional promoter did have the bi-directional transcriptional function in both expected orientations. The quantitative estimation of GUS and GFP were determined on a HITACHI F1000 Fluorescence Spectrophotometer with various wavelengths of excitation and emission. The GUS activity varied from g to 250 pmol 4-MU/min/mg protein and the GFP content varied from 0.9 to 1.8 μg/ mg protein in various lines of transgenic tobacco plants. Higher GUS activity generally coupled with lower GFP content, and vice versa. 展开更多
关键词 bi-directional promoter gusA gene gfp gene Nicotiana tabacum L. EXPRESSION
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Fast-Suppressor Screening for New Components in Protein Trafficking,Organelle Biogenesis and Silencing Pathway in Arabidopsis thaliana Using DEX-Inducible FREE1-RNAi Plants 被引量:3
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作者 Qiong Zhao Caiji Gao +20 位作者 PoShing Lee Lin Liu Shaofang Li Tangjin Hu Jinbo Shen Shuying Pan Hao Ye Yunru chen Wenhan Cao Yong Cui Peng Zeng Sheng Yu Yangbin Gao Liang chen Beixin Mo Xin Liu Shi Xiao Yunde Zhao Silin Zhong xuemei chen Liwen Jiang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2015年第6期319-330,共12页
Membrane trafficking is essential for plant growth and responses to external signals.The plant unique FYVE domain-containing protein FREE1 is a component of the ESCRT complex(endosomal sorting complex required for tr... Membrane trafficking is essential for plant growth and responses to external signals.The plant unique FYVE domain-containing protein FREE1 is a component of the ESCRT complex(endosomal sorting complex required for transport).FREE1 plays multiple roles in regulating protein trafficking and organelle biogenesis including the formation of intraluminal vesicles of multivesicular body(MVB),vacuolar protein transport and vacuole biogenesis,and autophagic degradation.FREE1 knockout plants show defective MVB formation,abnormal vacuolar transport,fragmented vacuoles,accumulated autophagosomes,and seedling lethality.To further uncover the underlying mechanisms of FREE1 function in plants,we performed a forward genetic screen for mutants that suppressed the seedling lethal phenotype of FREE1-RNAi transgenic plants.The obtained mutants are termed as suppressors of free1(sof).To date,229 putative sof mutants have been identified.Barely detecting of FREE1 protein with M3 plants further identified 84 FREE1-related suppressors.Also145 mutants showing no reduction of FREE1 protein were termed as RNAi-related mutants.Through next-generation sequencing(NGS)of bulked DNA from F2 mapping population of two RNAi-related sof mutants,FREE1-RNAi T-DNA inserted on chromosome 1 was identified and the causal mutation of putative sof mutant is being identified similarly.These FREE1-and RNAi-related sof mutants will be useful tools and resources for illustrating the underlying mechanisms of FREE1 function in intracellular trafficking and organelle biogenesis,as well as for uncovering the new components involved in the regulation of silencing pathways in plants. 展开更多
关键词 SUPPRESSORS FREE1 Endomembrane trafficking Arabidopsis NGS
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High-Voltage-Activated Calcium Channel in the Afferent Pain Pathway: An Important Target of Pain Therapies 被引量:2
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作者 Qi Li Jian Lu +4 位作者 Xiaoxin Zhou xuemei chen Diansan Su Xiyao Gu Weifeng Yu 《Neuroscience Bulletin》 SCIE CAS CSCD 2019年第6期1073-1084,共12页
High-voltage-activated(HVA) Ca^(2+)channels are widely expressed in the nervous system. They play an important role in pain conduction by participating in various physiological processes such as synaptic transmission,... High-voltage-activated(HVA) Ca^(2+)channels are widely expressed in the nervous system. They play an important role in pain conduction by participating in various physiological processes such as synaptic transmission, changes in synaptic plasticity, and neuronal excitability. Available evidence suggests that the HVA channel is an important therapeutic target for pain management. In this review, we summarize the changes in different subtypes of HVA channel during pain and present the currently available evidence from the clinical application of HVA channel blockers. We also review novel drugs in various phases of development. Moreover, we discuss the future prospects of HVA channel blockers in order to promote ‘‘bench-to-bedside'' translation. 展开更多
关键词 PAIN High-voltage-activated calcium channel Dorsal root ganglion
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幽门螺杆菌感染与皮肤疾病相关性的研究进展
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作者 陈雪梅 王玉婷 《临床医学进展》 2023年第5期7157-7163,共7页
幽门螺杆菌是一种革兰阴性菌,感染世界上约50%的人群,其常定植于胃黏膜中,与胃肠溃疡、慢性胃炎、胃癌等胃肠道疾病联系紧密。近年来研究发现,幽门螺杆菌感染还与许多皮肤病变相关,包括但不限于玫瑰痤疮、慢性荨麻疹、复发性阿弗他溃疡... 幽门螺杆菌是一种革兰阴性菌,感染世界上约50%的人群,其常定植于胃黏膜中,与胃肠溃疡、慢性胃炎、胃癌等胃肠道疾病联系紧密。近年来研究发现,幽门螺杆菌感染还与许多皮肤病变相关,包括但不限于玫瑰痤疮、慢性荨麻疹、复发性阿弗他溃疡、过敏性紫癜、免疫性血小板减少性紫癜等疾病。本文就幽门螺杆菌感染与皮肤疾病的研究进行综述,为临床决策提供帮助。 展开更多
关键词 幽门螺杆菌 皮肤疾病 根除治疗
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Microchannel cooling technique for dissipating high heat flux on W/Cu flat-type mock-up for EAST divertor
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作者 Mingxiang LU Le HAN +5 位作者 Qi ZHAO Juncheng QIU Jianhong ZHOU Dinghua HU Nanyu MOU xuemei chen 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第9期134-144,共11页
As an important component of tokamaks,the divertor is mainly responsible for extracting heat and helium ash,and the targets of the divertor need to withstand high heat flux of 10 MW m-2 for steady-state operation.In t... As an important component of tokamaks,the divertor is mainly responsible for extracting heat and helium ash,and the targets of the divertor need to withstand high heat flux of 10 MW m-2 for steady-state operation.In this study,we proposed a new strategy,using microchannel cooling technology to remove high heat load on the targets of the divertor.The results demonstrated that the microchannel-based W/Cu flat-type mock-up successfully withstood the thermal fatigue test of 1000 cycles at 10 MW m^(-2)with cooling water of 26 l min^(-1),30°C(inlet),0.8 MPa(inlet),15 s power on and 15 s dwell time;the maximum temperature on the heat-loaded surface(W surface)of the mock-up was 493°C,which is much lower than the recrystallization temperature of W(1200°C).Moreover,no occurrence of macrocrack and‘hot spot’at the W surface,as well as no detachment of W/Cu tiles were observed during the thermal fatigue testing.These results indicate that microchannel cooling technology is an efflcient method for removing the heat load of the divertor at a low flow rate.The present study offers a promising solution to replace the monoblock design for the EAST divertor. 展开更多
关键词 MICROCHANNEL DIVERTOR flat-type high heat flux test EAST
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Decision-Making Models Based on Meta-Reinforcement Learning for Intelligent Vehicles at Urban Intersections
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作者 xuemei chen Jiahe Liu +3 位作者 Zijia Wang Xintong Han Yufan Sun Xuelong Zheng 《Journal of Beijing Institute of Technology》 EI CAS 2022年第4期327-339,共13页
Behavioral decision-making at urban intersections is one of the primary difficulties currently impeding the development of intelligent vehicle technology.The problem is that existing decision-making algorithms cannot ... Behavioral decision-making at urban intersections is one of the primary difficulties currently impeding the development of intelligent vehicle technology.The problem is that existing decision-making algorithms cannot effectively deal with complex random scenarios at urban intersections.To deal with this,a deep deterministic policy gradient(DDPG)decision-making algorithm(T-DDPG)based on a time-series Markov decision process(T-MDP)was developed,where the state was extended to collect observations from several consecutive frames.Experiments found that T-DDPG performed better in terms of convergence and generalizability in complex intersection scenarios than a traditional DDPG algorithm.Furthermore,model-agnostic meta-learning(MAML)was incorporated into the T-DDPG algorithm to improve the training method,leading to a decision algorithm(T-MAML-DDPG)based on a secondary gradient.Simulation experiments of intersection scenarios were carried out on the Gym-Carla platform to verify and compare the decision models.The results showed that T-MAML-DDPG was able to easily deal with the random states of complex intersection scenarios,which could improve traffic safety and efficiency.The above decision-making models based on meta-reinforcement learning are significant for enhancing the decision-making ability of intelligent vehicles at urban intersections. 展开更多
关键词 DECISION-MAKING intelligent vehicles meta learning reinforcement learning urban intersections
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RAIENet:End-to-End Multitasking Road All Information Extractor
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作者 xuemei chen Pengfei Ren +2 位作者 Zeyuan Xu Shuyuan Xu Yaohan Jia 《Journal of Beijing Institute of Technology》 EI CAS 2024年第5期374-388,共15页
Road lanes and markings are the bases for autonomous driving environment perception.In this paper,we propose an end-to-end multi-task network,Road All Information Extractor named RAIENet,which aims to extract the full... Road lanes and markings are the bases for autonomous driving environment perception.In this paper,we propose an end-to-end multi-task network,Road All Information Extractor named RAIENet,which aims to extract the full information of the road surface including road lanes,road markings and their correspondences.Based on the prior knowledge of pavement information,we explore and use the deep progressive relationship between lane segmentation and pavement mark-ing detection.Then,different attention mechanisms are adapted for different tasks.A lane detection accuracy of 0.807 F1-score and a ground marking accuracy of 0.971 mean average precision at intersection over union(IOU)threshold 0.5 were achieved on the newly labeled see more on road plus(CeyMo+)dataset.Of course,we also validated it on two well-known datasets Berkeley Deep-Drive 100K(BDD100K)and CULane.In addition,a post-processing method for generating bird’s eye view lane(BEVLane)using lidar point cloud information is proposed,which is used for the construction of high-definition maps and subsequent decision-making planning.The code and data are available at https://github.com/mayberpf/RAIEnet. 展开更多
关键词 autonomous driving multitasking pavement marking detection lane segmentation pavement information
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Investigation on the Resources of Paris Polyphylla var.yunnanensis
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作者 Shicai WU Guo LI +5 位作者 Qiping WANG Wenli YANG xuemei chen Jian FENG Ganghua LI Shaoshan ZHANG 《Medicinal Plant》 CAS 2020年第6期27-30,共4页
In this study,the resource distribution,morphological characteristics,artificial cultivation and market circulation of Paris Polyphylla var.yunnanensis and its polygerm varieties in Yunnan were investigated by referri... In this study,the resource distribution,morphological characteristics,artificial cultivation and market circulation of Paris Polyphylla var.yunnanensis and its polygerm varieties in Yunnan were investigated by referring to the research literature,field investigation and our planting experience.It is found that P.polyphylla var.yunnanensis is widely distributed in Yunnan Province,realizing large-scale artificial cultivation,while the wild resources of polygerm varieties are almost on the verge of extinction and are in urgent need of protection. 展开更多
关键词 Paris Polyphylla var.yunnanensis Resource distribution CULTIVATION INVESTIGATION
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Optimization of Temperature Drop Formula for Annular Gathering Pipeline in High Water Cut Oil Region of Central Hebei Province
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作者 Haonan Cai Lining Zhao +5 位作者 xuemei chen Xintong chen Tong Guan Jinxiu Wang Bolin Lv Shuaibin Li 《Journal of Power and Energy Engineering》 2018年第9期21-26,共6页
In order to respond to the national policy of energy saving and consumption reduction, the temperature drop formula of annular pipeline should be established to optimize the water mixing temperature and water mixing f... In order to respond to the national policy of energy saving and consumption reduction, the temperature drop formula of annular pipeline should be established to optimize the water mixing temperature and water mixing flow. The traditional temperature drop formula applies the high water cut actual situation to 13.7%. On the basis of the traditional Schulhof temperature drop formula, the influence of hydraulic friction on the oil flow temperature is calculated by the calculus idea. The heat transfer coefficient of the pipeline under the complex condition is obtained by the inverse algorithm, and the water mixing flow and water temperature are simulated with MATLAB. The function surface diagram of the degree and the back station temperature. The actual error can be reduced to 4.8%, and the return station temperature can be optimized by 7 degrees. 展开更多
关键词 Circular Water COLLECTING Oil Hydraulic Friction INVERSE Algorithm SAVING Energy Cost
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The Application of Task-based Approach to Senior High School English Teaching
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作者 xuemei chen 《Journal of Zhouyi Research》 2014年第4期19-22,共4页
关键词 任务教学法 英语教学 应用 高中 青少年学生 教学方法 教学过程 教学模式
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Dynamics of neutralizing antibodies against COVID-19 Omicron subvariants following breakthrough infection in southwest China between December 2022 and April 2024
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作者 Yongquan He Yi Yin +15 位作者 Yi Zhang Huiping Yang Zhiling Jiang Fang Hao Taiqiang Zhao Xiaobin Liu Yusong Liu Yong Zeng Xi Li xuemei chen Kaiju Xu Chang Tan Jie Yang Li Jiang Bo Gong Zhenglin Yang 《Signal Transduction and Targeted Therapy》 2025年第8期4778-4784,共7页
From December 2022 to January 2023,the SARS-CoV-2 Omicron BA.5/BF.7 variant significantly impacted China’s mainland.While most COVID-19 patients experienced mild symptoms and were treated as outpatients or at home,so... From December 2022 to January 2023,the SARS-CoV-2 Omicron BA.5/BF.7 variant significantly impacted China’s mainland.While most COVID-19 patients experienced mild symptoms and were treated as outpatients or at home,some cases progressed to severe illness,necessitating hospitalization or even resulting in death.To better understand this outbreak and forecast future waves as SARS-CoV-2 continues to evolve,it is crucial to assess the titer of neutralizing antibodies(Nab)for evaluating the establishment of an immune barrier.In this study,we investigated the dynamic evolution of humoral immunity following the breakthrough infection wave driven by the SARS-CoV-2 Omicron BA.5/BF.7 variant in southwest China. 展开更多
关键词 Omicron BA BF neutralizing antibodies nab humoral immunity neutralizing antibodies establishment immu SARS COV dynamic evolution breakthrough infection
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Research on vertical strategy for left turn at signal-free T-shaped intersections based on multi-layer reinforcement learning methods
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作者 xuemei chen Jia Wu +1 位作者 Jiachen Hao Yixuan Yang 《Green Energy and Intelligent Transportation》 2025年第5期104-112,共9页
The task of executing left turns at signal-free T-shaped intersections without protective signals poses a criticalchallenge in the realm of autonomous driving. Conventional rule-based approaches tend to be excessively... The task of executing left turns at signal-free T-shaped intersections without protective signals poses a criticalchallenge in the realm of autonomous driving. Conventional rule-based approaches tend to be excessivelycautious, rendering them inadequate for effectively managing driving tasks within unpredictable T-shapedintersection environments. In the case of complex traffic scenarios, a single model is less effective in convergenceand has a lower pass rate and poorer safety. Thus, this study introduces a multi-layer reinforcement learningmodel, employing D3QN (Dueling Double DQN) and TD3 (Twin Delayed Deep Deterministic policy gradientalgorithm) for advanced behavioral decision-making and vertical acceleration planning, respectively. In ourexperimental investigation, we designed four simulation scenarios based on the driving behavior of the Carlasimulator to replicate real-world driving conditions. Verification and test simulation outcomes substantiate that,in comparison to other single-trained reinforcement learning models, the multi-layer reinforcement learningmodel proposed in this study attains the highest success rate. Specifically, the pass rate in the verification scenario,consistent with the training conditions, achieves an impressive 99.5%. Furthermore, the pass rate in thecomprehensive test scenario reaches 89.6%. These experiments unequivocally demonstrate the considerableenhancement in T-shaped intersections pass rates achieved by the proposed method while ensuring both trafficefficiency and safety. 展开更多
关键词 Autonomous driving T-shaped intersection Reinforcement learning Accelerate planning
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