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Dependence of magnetic field just inside the magnetopause on subsolar standoff distance:Global MHD results

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Chinese Science Bulletin 2012年第12期57卷 1438-1442页

作者： wang ming lu jianyong liu ziqian pei shixin College of Math ＆ Physics Nanjing University of Information Science ＆ Technology Nanjing 210044 China National Center for Space Weather China Meteorology Administration Beijing 100081 China Chinese Academy of Meteorological Sciences Beijing 100081 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The subsolar magnetopause is the boundary between the solar wind and the Earth's magnetosphere,where reduced solar wind dynamic pressure is equal to the magnetic pressure of the Earth's outer *** use a global magnetohydrodynamic (MHD)model to estimate the ratio f of the compressed magnetic field just inside the subsolar magnetopause to the purely dipolar magnetic *** also compare our numerical results to a similar work by Shue,which used Time History of Events and Macroscale Interactions during Substorms(THEMIS)*** results show that the ratio f is linearly proportional to the subsolar magnetopause standoff distance(r0)for both the northward and southward interplanetary magnetic field,properties consistent with Shue but with a smaller proportionality ***,previous theoretical studies show that f is nearly independent of the subsolar standoff *** global model results also show that f is smaller for the southward Interplanetary Magnetic Field(IMF)under the same r0,and that the proportionality constant for the southward IMF is larger than that for the northward *** conclusions agree with statistical results from observations by Shue.

关键词：行星际磁场地球磁层磁流体距离国际货币基金组织模型估计相互作用历史事件

PIM1-HDAC2 axis modulates intestinal homeostasis through epigenetic modification

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Acta Pharmaceutica Sinica B 2024年第7期14卷 3049-3067页

作者： Jianming Yang Yawen Xiao Ningning Zhao Geng pei Yan Sun Xinyu Sun Kaiyuan Yu Chunhui Miao Ran liu Junqiang Lv Hongyu Chu lu Zhou Bangmao wang Zhi Yao Quan wang Key Laboratory of Immune Microenvironment and Disease(Ministry of Education) Tianjin Institute of ImmunologyState Key Laboratory of Experimental Hematologythe Province and Ministry Co-sponsored Collaborative Innovation Center for Medical EpigeneticsDepartment of ImmunologySchool of Basic Medical SciencesTianjin Institute of Urologythe Second Hospital of Tianjin Medical UniversityTianjin Key Laboratory of Cellular and Molecular ImmunologyTianjin Medical UniversityTianjin 300070China Department of Pathology Tianjin Medical University Cancer Institute and Hospital/National Clinical Research Center of Cancer/Key Laboratory of Cancer Prevention and TherapyTianjin/Tianjin’s Clinical Research Center of CancerTianjin 30060China Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalTianjin Medical UniversityTianjin 300070China

The mucosal barrier is crucial for intestinal homeostasis,and goblet cells are essential for maintaining the mucosal barrier *** proviral integration site for Moloney murine leukemia virus-1(PIM1)kinase regulates multiple cellular functions,but its role in intestinal homeostasis during colitis is ***,we demonstrate that PIM1 is prominently elevated in the colonic epithelia of both ulcerative colitis patients and murine models,in the presence of intestinal *** PIM1 leads to decreased goblet cells,thus impairing resistance to colitis and colitis-associated colorectal cancer(CAC)in ***,PIM1 modulates goblet cell differentiation through the Wnt and Notch signaling ***,PIM1 interacts with histone deacetylase 2(HDAC2)and downregulates its level via phosphorylation,thereby altering the epigenetic profiles of Wnt signaling pathway ***,these findings investigate the unknown function of the PIM1-HDAC2 axis in goblet cell differentiation and ulcerative colitis/CAC pathogenesis,which points to the potential for PIM1-targeted therapies of ulcerative colitis and CAC.

关键词： PIM1 HDAC2 Goblet cell Gut microbiota Intestinal homeostasis Epigenetic modification Ulcerative colitis CAC

Detector performance of the Gamma-ray Transient Monitor onboard DRO-A satellite

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 75-90页

作者： pei-Yi Feng Zheng-Hua An Da-Li Zhang Chen-Wei wang Chao Zheng Sheng Yang Shao-Lin Xiong Jia-Cong liu Xin-Qiao Li Ke Gong Xiao-Jing liu Min Gao Xiang-Yang Wen Ya-Qing liu Xiao-Yun Zhao Fan Zhang Xi-Lei Sun Hong lu Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

The Gamma-ray Transient Monitor(GTM) is an all-sky monitor onboard the Distant Retrograde Orbit-A(DRO-A) satellite with the scientific objective of detecting gamma-ray transients ranging from 20 ke V to 1 MeV. The GTM was equipped with five Gamma-ray Transient Probe(GTP) detector modules utilizing a NaI(Tl) scintillator coupled with a SiPM array. To reduce the SiPM noise, GTP uses a dedicated dual-channel coincident readout design. In this work, we first studied the impact of different coincidence times on the detection efficiency and ultimately selected a 0.5 μs time coincidence window for offline data processing. To test the performance of the GTPs and validate the Monte-Carlo-simulated energy response, we conducted comprehensive ground calibration tests using the Hard X-ray Calibration Facility(HXCF) and radioactive sources, including the energy response, detection efficiency, spatial response, bias-voltage response, and temperature dependence. We extensively present the ground calibration results and validate the design and mass model of the GTP detector, thus providing the foundation for in-flight observations and scientific data analysis.

关键词： NaI(Tl)detector energy response ground calibration gamma-ray detector DRO-A satellite

Dependence of magnetic field just inside the magnetopause on subsolar standoff distance:global MHD results

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Dependence of magnetic field just inside the magnetopause on...

第十四届全国日地空间物理学术研讨会

作者： wang ming1,2.lu jianyong1,2.liu ziqian3.pei shixin1 (1 College of Math & Physics, Nanjing University of Information Science & Technology, Nanjing 210044, China ) (2 National Center for Space Weather, China Meteorology Administration, Beijing 100081, China ) (3 Chinese Academy of Meteorological Science, Graduate University of Chinese Academy of Science, Beijing 100081, China )

The subsolar magnetopause is the boundary of solar wind and the Earth’s magnetosphere where reduced solar wind dynamic pressure is equal to the magnetic pressure of the Earth’s outer magnetosphere. We use a global MHD model to estimate the ratio （f） of the compressed magnetic field just inside the subsolar magnetopause to the purely dipolar magnetic field. We also compared our numerical results with a similar work by Shue with the THEMIS data. Our results show that the ratio f is linearly proportional to the subsolar magnetopause standoff distance （r0） for both northward and southward interplanetary magnetic field, which in property is consistent with Shue’s result but the proportionality constant is smaller, although previous theoretical studies show that the ratio f is nearly independent of the subsolar standoff distance. The global model results also show that the ratio f is smaller for the southward IMF under the same r0 and the proportionality constant for the southward IMF is larger than that for the northward IMF. Both conclusions agree with statistical results from observations by Shue.

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太赫兹多维复用与折射率传感集成器件

光学学报 2024年第8期44卷 229-241页

作者：揭璐李海粟刘亚静王建帅任国斌裴丽北京交通大学光波技术研究所全光网络与现代通信网教育部重点实验室北京100044

提出了一种基于亚波长偏振保持光纤的多维复用与折射率(RI)传感集成器件。该器件由定向耦合器、Y型分束器和布拉格光栅器件构成,能够同时实现三维空间中偏振和频率(解)复用、色散补偿以及RI传感功能。集成器件下行端口输出偏振解复用后... 详细信息

提出了一种基于亚波长偏振保持光纤的多维复用与折射率(RI)传感集成器件。该器件由定向耦合器、Y型分束器和布拉格光栅器件构成,能够同时实现三维空间中偏振和频率(解)复用、色散补偿以及RI传感功能。集成器件下行端口输出偏振解复用后的x偏振态,其在0.25 THz频率处的传输率和消光比分别为-5.94 dB和15.16 dB。此后,原波导中y偏振态(工作频率为0.25 THz)与x偏振态(工作频率为0.27 THz)复用后于直通端口输出,传输率分别为-7.20 dB和-2.02 dB。同时,集成的均匀光栅和π相移光栅可分别实现色散补偿(群速度色散为-109.4 ps·THz^(-1)·mm^(-1))和RI传感(灵敏度为0.181 THz/RIU)功能。基于太赫兹亚波长光纤的集成器件在下一代通感一体化信息系统中具有良好的应用前景。

关键词：光学器件太赫兹耦合器复用器传感器

新疆库尔勒八字地老虎在不同温度下的种群生命表及灯下成虫种群动态

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昆虫学报 2024年第2期67卷 246-254页

作者：楚士娇刘冰王佩玲陆宴辉石河子大学农学院新疆绿洲农业病虫害治理与植保资源利用重点实验室石河子832003 中国农业科学院植物保护研究所植物病虫害综合治理全国重点实验室北京100193

【目的】研究温度对新疆库尔勒八字地老虎Xestia c-nigrum生长发育和繁殖的影响,明确其对环境温度的适应能力。【方法】利用两性生命表方法比较15, 20, 25, 30和35℃下八字地老虎卵孵化率、幼虫存活率、化蛹率、羽化率、发育历期及繁殖... 详细信息

【目的】研究温度对新疆库尔勒八字地老虎Xestia c-nigrum生长发育和繁殖的影响,明确其对环境温度的适应能力。【方法】利用两性生命表方法比较15, 20, 25, 30和35℃下八字地老虎卵孵化率、幼虫存活率、化蛹率、羽化率、发育历期及繁殖力,分析不同温度对其种群生命表参数的影响,并计算不同发育阶段的发育起点温度和有效积温。利用灯诱监测数据分析2020-2022年期间新疆库尔勒农区八字地老虎种群动态与日平均温度变化的关系。【结果】15℃时八字地老虎幼虫存活率、化蛹率、羽化率均低于30%,30℃时幼虫存活率、化蛹率低于10%且蛹不能正常羽化,35℃时幼虫不能存活。八字地老虎各发育阶段历期随温度升高而缩短,15, 20, 25, 30和35℃时卵历期分别为15.52, 7.40, 5.47, 4.88和3.88 d;15, 20, 25和30℃时幼虫历期分别为109.43, 40.53, 26.48和24.55 d;15, 20和25℃时蛹历期分别为41.43, 18.00和12.54 d。15℃时种群呈负增长,20和25℃时种群呈正增长,其中25℃时内禀增长率(r_m)最大。八字地老虎卵、1-6龄幼虫和蛹的发育起点温度分别为9.81, 8.43,9.95, 10.26, 12.52, 13.58, 12.60和10.81℃,有效积温依次为79.62, 92.17, 56.09, 57.03, 39.35, 38.16, 80.72和172.39日·度。2020-2022年灯诱监测数据表明,八字地老虎在新疆库尔勒每年发生3代,成虫高峰期分别在5月中旬、7月下旬和9月上旬,对应的日平均温度在19.5~26.5℃之间。【结论】低于15℃时八字地老虎种群呈负增长,超过30℃时不能完成生活史,而20~25℃比较适合八字地老虎的生长与繁殖,该结果为明确新疆库尔勒八字地老虎的温度适应能力及其发生规律提供了科学依据。

关键词：八字地老虎生命表参数温度发育历期种群动态两性生命表

Cortactin/N-cadherin信号轴在病理性心肌肥大中的作用

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中国药理学通报 2024年第2期40卷 234-242页

作者：王钺镁喻文静孙袭孟张静路静刘培庆中山大学药学院广东广州510006

目的探究皮层肌动蛋白结合蛋白(Cortactin)对异丙肾上腺素(isoprenaline,ISO)诱导的病理性心肌肥大的调控作用及其机制。方法采用ISO刺激新生大鼠心肌细胞(neonatal rat cardiomyocytes,NRCMs)24 h,在细胞水平建立心肌肥大模型;C57BL/6... 详细信息

目的探究皮层肌动蛋白结合蛋白(Cortactin)对异丙肾上腺素(isoprenaline,ISO)诱导的病理性心肌肥大的调控作用及其机制。方法采用ISO刺激新生大鼠心肌细胞(neonatal rat cardiomyocytes,NRCMs)24 h,在细胞水平建立心肌肥大模型;C57BL/6小鼠皮下注射ISO 1周,在动物水平建立心肌肥大模型。采用RT-qPCR检测mRNA的变化;免疫印迹法检测相应蛋白含量的变化;免疫荧光法检测Cortactin的亚细胞定位及表达量的变化;采用腺病毒感染的方法过表达Cortactin,通过转染小干扰RNA敲低Cortactin。结果在细胞和动物水平上,成功建立ISO诱导的心肌肥大模型,均观察到ISO引起Cortactin和N型钙黏连蛋白(N-cadherin)水平降低;过表达Cortactin可逆转ISO导致的N-cadherin蛋白水平的降低及心肌细胞肥大反应;敲低Cortactin则显示相反的效应。结论Cortactin可能联合N-cadherin通过增强心肌细胞之间的连接,发挥抗心肌肥大的作用。

关键词：异丙肾上腺素心肌肥大心肌细胞肌动蛋白结合蛋白 N-cadherin 细胞连接

Mechanism of Polymorph Selection during Crystallization of Random Butene-1/Ethylene Copolymer

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Chinese Journal of Polymer Science 2016年第8期34卷 1014-1020页

作者： Yao-tao wang pei-ru liu Ying lu 门永锋 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Starting from an initial sample of butene-1/ethylene copolymer with stable form I＇, we examined the nucleation of different crystalline polymorphs （here metastable form II and stable form I＇） at different isothermal crystallization temperatures after being melted at different melt temperature （Tmelt）. When Tmelt was just above the melting temperature （Tm） of the crystallites, self-seeding took place. There, residue crystallites served as nuclei leading to the crystallization of the same crystalline phase. When Tmelt was a few degrees above the Tin, self-seeding was disabled due to complete melting of the initial crystals. Upon crystallization, the selection of the different polymorphs in this random copolymer was found to depend on an interplay between the domain size of segregated long crystallizable sequences and the size and energy barrier of the critical nucleus of the respective crystalline forms. Our results provide a clear understanding of the polymorphs selection during crystallization of a random copolymer as well as homo-polymers under confinement.

关键词： Crystallization Random copolymer Polybutene-1 Polymorphism.

心脏磁共振影像组学对肥厚型心肌病的价值研究

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磁共振成像 2024年第2期15卷 30-41页

作者：吕静朱永琪朱彦芳何瑛王艺霖王霈朱力刘云宁夏医科大学临床医学院银川750004 宁夏人民医院医学影像中心银川750002 银川市妇幼保健院医务科银川750299 宁夏医科大学总医院放射科银川750004

目的初步探索基于心脏磁共振(cardiovascular magnetic resonance,CMR)影像组学揭示肥厚型心肌病(hypertrophic cardiomyopathy,HCM)患者心肌病变影像组学特征的临床应用价值。材料与方法回顾性分析宁夏医科大学总医院2018年1月1日至202... 详细信息

目的初步探索基于心脏磁共振(cardiovascular magnetic resonance,CMR)影像组学揭示肥厚型心肌病(hypertrophic cardiomyopathy,HCM)患者心肌病变影像组学特征的临床应用价值。材料与方法回顾性分析宁夏医科大学总医院2018年1月1日至2022年12月31日确诊为HCM的患者142例及健康对照组72例的CMR影像及临床资料。选择CMR未增强亮血电影序列左心室长轴位两腔心、四腔心二尖瓣口水平切面,以舒张末期壁厚(end-diastolic wall thickness,EDWT)为基础,将HCM患者心肌分为肥厚区域(无HCM家族史,EDWT≥15 mm;有HCM家族史,EDWT≥13 mm)与非肥厚区域(无HCM家族史,EDWT15 mm;有HCM家族史,EDWT13 mm),和健康对照组在室间隔、心尖、左心室侧壁、左心室前壁及左心室下壁等相同解剖部位室壁分别进行感兴趣区(region of interest,ROI)勾画及影像组学特征提取,分组后行影像组学特征组间比较。采用Mann-Whitney U检验、递归特征消除法(recursive feature elimination,RFE)及最小绝对收缩与选择算法(least absolute shrinkage and selection operator,LASSO)进行影像组学特征筛选并使用支持向量机(supportvector machine,SVM)算法建立影像组学模型,最后计算准确度、敏感度、特异度、阳性预测值(positive predictive value,PPV)、阴性预测值(negative predictive value,NPV)受试者操作特征曲线下面积(area under the curve,AUC),分别评价各模型效能;并统计分析HCM患者及健康对照组临床资料。结果(1)HCM组的左心室收缩末期容积(left ventricular end systolic volume,LVESV)、LVESV指数(LVESV index,LVESVI)、左心室舒张末期室壁质量(left ventricular end diastolic wall mass,LVED wall mass)、左心室舒张末期室壁+乳头肌质量(left ventricular end diastolic wall+papillary mass,LVED wall+papillary mass)、左心室收缩末期室壁质量(left ventricular end systolic wall mass,LVES wall mass)、左心室收缩末期室壁+乳头肌质量(left ventricular end systolic wall+papillary mass,LVES wall+papillary mass)、舒张末期左室壁最大厚度(left ventricular maximum wall thickness,LVMWT)均高于健康对照组(P2)HCM患者肥厚区域、非肥厚区域与健康对照组左心室相同解剖部位室壁影像组学鉴别模型鉴别效果良好;HCM非肥厚区域组(左心室前壁)与HCM肥厚区域组(左心室前壁)影像组学鉴别模型为本研究的最优模型,其AUC值、准确度、敏感度、特异度、PPV及NPV在训练集中为0.98、93%、94%、92%、89%、96%;在测试集中为0.97、94%、92%、96%、92%、96%。结论影像组学可通过深入全面的定量分析HCM患者不同病变状态心肌组织,为评估HCM患者心肌组织学改变提供客观敏感的新方法,有助于更准确地评估HCM患者病情、提高CMR检查效率及减少检查费用,有望为探寻方便快捷检测心肌组织学状态的人工智能技术开发及临床应用提供新思路。

关键词：肥厚型心肌病心脏磁共振影像组学磁共振成像电影序列支持向量机