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Development of Gravity Theories in the View of TRAPPIST-1e

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Research in Astronomy and Astrophysics 2025年第1期25卷 143-161页

作者： Nan wang Lu-Yao Lu Hui-Gen Liu An-Dong Chen Tiger Lu ao-Ran Cui Jun-Kai wang Marine Science and Technology College Zhejiang Ocean University Key Laboratory of Modern Astronomy and Astrophysics Ministry of Education Zhoushan Astronomical Society School of Astronomy and Space Science Nanjing University Department of Astronomy Yale University Kuang Yaming Honors School Nanjing University School of Physics Nanjing University

Contrary to the solar system, most exoplanet systems detected hitherto are close-in and compact. One typical system is TRAPPIST-1, which has seven nearly co-planar terrestrial planets all within the orbit of Mercury,including three in the habitable zone. To evaluate the differences in developing sophisticated gravity theories from the solar system, we use N-body integrations to simulate ephemeris and reproduce some important astronomy phenomena observed on the potentially habitable planet TRAPPIST-1e. Retrograde motions of other planets last1–2 orders of magnitude shorter than in the solar system, but occur much more frequently. Transit events of all inner planets can be observed steadily. Except for Kepler's first law, which is hard to notice for low eccentricities of planets, the other two laws can then be precisely verified in 102days, because the areas swept by planets vary by?0.01% and the observed semimajor axes and periods result in constants with theoretical and observation accuracies both ?2%. However, the mean motion correlation implies that the Great Inequality is not always apparent between one pair of planets like Jupiter and Saturn. Furthermore, general relativity can hardly be discovered because it gives rise to perihelion precession of inner planets only ～0.1% of gravity precession, dozens of times smaller than Mercury. Our results support the possibility of developing part of gravity theories by potential exo-civilizations in compact systems like TRAPPIST-1.

关键词： ephemerides extraterrestrial intelligence gravitation planets and satellites: terrestrial planets

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复杂应力状态下土料三轴渗透试验

河海大学学报（自然科学版） 2017年第5期45卷 451-456页

作者：凌华张胜敖大华王芳韩华强南京水利科学研究院水文水资源与水利工程科学国家重点实验室江苏南京210029 水利部土石坝破坏机理与防控技术重点实验室江苏南京210029 中国电建集团贵阳勘测设计研究院有限公司贵州贵阳550081

为研究高土石坝坝体内土体单元在复杂应力状态下的渗透性能,在中型三轴仪上对同一土料场3种不同级配土料进行三轴渗透试验。试验围压分为5级(100 k Pa、400 k Pa、800 k Pa、1 200k Pa和2 000 k Pa),每级围压下分4种应力水平(0、0.2、0.... 详细信息

为研究高土石坝坝体内土体单元在复杂应力状态下的渗透性能,在中型三轴仪上对同一土料场3种不同级配土料进行三轴渗透试验。试验围压分为5级(100 k Pa、400 k Pa、800 k Pa、1 200k Pa和2 000 k Pa),每级围压下分4种应力水平(0、0.2、0.4和0.8),当试样在初始应力状态下变形基本稳定后,采用常水头法测试试样的渗透系数。试验结果表明:级配是影响渗透系数的重要因素,相同应力条件下土料粉粒和黏粒含量越高,渗透系数越小;随围压和应力水平的提高,土料的渗透系数逐渐降低;粉粒和黏粒含量越低、大颗粒含量越高,围压对土料渗透系数的影响越显著;对于不同级配相同密实度试样,应力水平对渗透系数的影响程度基本一致。在分析渗透系数随围压和应力水平变化规律的基础上,建立了能描述复杂应力状态条件下土体渗透系数的经验公式。

关键词：复杂应力状态三轴渗透试验中型三轴仪渗透系数围压应力水平颗粒级配常水头法

DNMT1 promotes the proliferation and migration of gastric cancer cells by inducing microRNA-125a-5p methylation to promote SERPINE1 protein

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World Journal of Gastrointestinal Oncology 2025年第3期17卷 188-201页

作者： Hui Xie Hui wang Ru-Hong Li Yue-Wen Zhang Xi-Rui Fan Xiao-Xue He ao-Ran Guan Department of General Surgery Yan’an Hospital of Kunming CityKunming 650051Yunnan ProvinceChina Department of Digestive Internal Medicine Yan’an Hospital of Kunming CityKunming 650051Yunnan ProvinceChina

BACKGROUND Gastric cancer(GC)is a malignant tumor originating from gastric mucosal epithelial cells that has high morbidity and ***(miR)are important diagnostic markers and therapeutic targets in this *** To explore the mechanism of miR-125a-5p in the pathogenesis of *** The expression levels of miR-125a-5p,SERPINE1 and DNMT1 in GC cells and tissues were detected by real-time polymerase chain reaction(PCR)and Western ***-specific PCR was used to detect the level of miR-125a-5p methylation.A cell counting kit 8 assay,scratch test,and a Transwell assay were performed to detect the proliferation,migration,and invasiveness of HGC27 cells,*** expression of the epithelial mesenchymal transition(EMT)-related proteins E-cadherin,N-cadherin and vimentin in HGC27 cells was detected by Western blotting,while the expression of vimentin was detected by *** This study revealed that miR-125a-5p was expressed at low levels in GC clinical samples and cells and that miR-125a-5p overexpression inhibited the proliferation,migration,invasiveness and EMT of GC ***,miR-125a-5p can reduce GC cell proliferation,promote E-cadherin expression,inhibit N-cadherin and vimentin expression,and reduce the EMT of GC cells,thus constraining GC cells to a certain ***,DNMT1 inhibited miR-125a-5p expression by increasing the methylation of the miR-125a-5p promoter,thereby promoting the expression of SERPINE1,which acts together with miR-125a-5p to exert antagonistic effects on *** Our study revealed that DNMT1 promoted SERPINE1 protein expression by inducing miR-125a-5p methylation,which led to the proliferation,migration and occurrence of EMT in GC cells.

关键词： Gastric cancer microRNA-125a-5p DNA methyltransferase 1 SERPINE1 Methylation

不同几何尺寸SiC微粒对机床导轨材料GCr15的磨损机制

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表面技术 2025年第1期54卷 140-149页

作者：王奔史忠澳祝天龙张棋沈阳航空航天大学机电工程学院沈阳110000

目的探究不同几何尺寸SiCf/SiC陶瓷基复合材料切屑对机床精密部件磨损性能的影响机制及磨损机理,为机床防护提供理论参考。方法以机床精密部件——导轨运动副为例,利用SiC磨粒代替SiCf/SiC陶瓷基复合材料切屑,采用机床导轨运动副材料GC... 详细信息

目的探究不同几何尺寸SiCf/SiC陶瓷基复合材料切屑对机床精密部件磨损性能的影响机制及磨损机理,为机床防护提供理论参考。方法以机床精密部件——导轨运动副为例,利用SiC磨粒代替SiCf/SiC陶瓷基复合材料切屑,采用机床导轨运动副材料GCr15轴承钢,在不同几何尺寸磨粒条件下进行销盘摩擦磨损试验,采用宏观摩擦因数和微观磨损形貌对磨损表面进行表征,探究磨损机制。结果相较于无磨粒条件下,在加入磨粒后其摩擦因数更高、更不稳定。在磨粒条件下,GCr15轴承钢的磨损表面存在大量的平行凹槽和不规则压痕,并伴随着少量的剥落坑。随着磨粒尺寸的增加,损伤加重,平行凹槽磨损更深、更宽,表面材料的剥落坑更密集,同时,磨粒几何尺寸的增加导致更深的磨痕深度及更高的磨损量。结论磨粒在摩擦界面存在游离和结合等2种运动形式,磨损机制为滚动挤压磨损与滑动开槽磨损的结合,且随着磨粒几何尺寸的增大,磨损机制由磨粒滚动挤压过渡为滑动开槽主导;1μm和5μm磨粒对摩擦进程的影响主要体现在剧烈磨损阶段,而10μm和20μm磨粒对整个进程都有明显影响,且大尺寸磨粒的加入会使摩擦副提前进入剧烈阶段;对比不同条件下的磨损形貌、摩擦因数及磨损量可知,1μm和5μm的磨粒对摩擦的影响较小。

关键词：机床导轨销盘试验三体磨粒磨损摩擦磨损性能磨损机制

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Cr-Ni-Mo-Ti马氏体时效不锈钢热锻环粗晶粒的遗传及细化

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金属热处理 2025年第1期50卷 169-173页

作者：丁雅莉高齐王敖钢铁研究总院有限公司特殊钢研究院北京100081

针对Cr-Ni-Mo-Ti马氏体时效不锈钢热锻环的晶粒粗大问题,研究了锻态粗晶的遗传温度范围,确定了细化晶粒的再结晶温度(T_(re)),同时研究了重复加热/冷却的晶粒细化效应以及其对力学性能的影响。结果表明:在试验钢Af以上很宽的温度范围内... 详细信息

针对Cr-Ni-Mo-Ti马氏体时效不锈钢热锻环的晶粒粗大问题,研究了锻态粗晶的遗传温度范围,确定了细化晶粒的再结晶温度(T_(re)),同时研究了重复加热/冷却的晶粒细化效应以及其对力学性能的影响。结果表明:在试验钢Af以上很宽的温度范围内遗传锻态粗晶,950℃附近固溶处理后形成晶界完全封闭、明显细化的奥氏体晶粒,表明再结晶温度T_(re)≈950℃,进一步提高固溶温度时晶粒持续长大;略低于950℃重复加热/冷却时晶界大幅迁移形成晶界未封闭、尺寸明显细化的晶粒,在950℃重复加热/冷却仍有细化晶粒作用,但进一步提高温度重复加热/冷却时的晶粒细化作用减弱,1050℃重复加热/冷却不再有晶粒细化效果;875℃重复加热/冷却时细化晶粒能明显改善其冲击性能,但抗拉强度和屈服强度下降,表现出强度随晶粒尺寸细化而下降的现象;925℃和975℃(T_(re)附近)加热/冷却1次的强度和韧性与875℃加热/冷却3次的接近,虽然重复加热/冷却时晶粒略有细化,但力学性能无明显变化。

关键词：马氏体时效不锈钢锻态粗晶粗晶遗传再结晶重复加热/冷却

A genome-wide association study and transcriptome analysis reveal the genetic basis for the Southern corn rust resistance in maize

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Journal of Integrative Agriculture 2025年第2期24卷 453-466页

作者： Yang wang Chunhua Mu Xiangdong Li Canxing Duan Jianjun wang Xin Lu wangshu Li Zhennan Xu Shufeng Sun ao Zhang Zhiqiang Zhou shenghui Wen Zhuanfang Hao Jienan Han Jianzhou Qu Wanli Du Fenghai Li Jianfeng Weng College of Agronomy Shenyang Agricultural University Institute of Crop Sciences Chinese Academy of Agricultural Sciences Institute of Maize Research Shandong Academy of Agricultural Sciences College of Plant Protection Shandong Agricultural University Institute of Maize Shanxi Agricultural University

Southern corn rust(SCR) is an airborne fungal disease caused by Puccinia polysora Underw.(P. polysora) that adversely impacts maize quality and yields worldwide. Screening for new elite SCR-resistant maize loci or genes has the potential to enhance overall resistance to this pathogen. Using phenotypic SCR resistance-related data collected over two years and three geographical environments, a genome-wide association study was carried out in this work, which eventually identified 91 loci that were substantially correlated with SCR susceptibility. These included 13 loci that were significant in at least three environments and overlapped with 74 candidate genes(B73＿RefGen＿v4). Comparative transcriptomic analyses were then performed to identify the genes related to SCR infection, with 2,586 and 797 differentially expressed genes(DEGs) ultimately being identified in the resistant Qi319and susceptible 8112 inbred lines following P. polysora infection, respectively, including 306 genes common to both lines. Subsequent integrative multi-omics investigations identified four potential candidate SCR response-related genes. One of these genes is ZmHCT9, which encodes the protein hydroxycinnamoyl transferase 9. This gene was up-regulated in susceptible inbred lines and linked to greater P. polysora resistance as confirmed through cucumber mosaic virus(CMV)-based virus induced-gene silencing(VIGS) system-mediated gene silencing. These data provide important insights into the genetic basis of the maize SCR response. They will be useful for for future research on potential genes related to SCR resistance in maize.

关键词： maize southern corn rust genome-wide association study transcriptome

Synthesis of lutetium hydrides at high pressures

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Matter and Radiation at Extremes 2025年第1期10卷 98-104页

作者： Yuan-ao Peng Han-Yu wang Fu-Hai Su Pu wang Hai-An Xu Lin Liu Lun-Xuan Yu Ross T.Howie Wan Xu Eugene Gregoryanz Xiao-Di Liu University of Science and Technology of China Hefei 230026China Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China Centre for Science at Extreme Conditions and School of Physics and Astronomy University of EdinburghEdinburgh EH93FDUnited Kingdom Center for High Pressure Science and Technology Advanced Research Shanghai 201203China

High-pressure synthesis of lutetium hydrides from molecular hydrogen(H_(2))and lutetium(Lu)is systematically investigated using synchrotron X-ray diffraction,Raman spectroscopy,and visual *** demonstrate that the reaction pathway between H_(2)and Lu invariably follows the sequence Lu→LuH_(2)→LuH_(3)and exhibits a notable time dependence.A comprehensive diagram representing the formation and synthesis of lutetium hydrides as a function of pressure and time is *** findings indicate that the synthesis can be accelerated by elevated temperature and decelerated by increased ***,two critical pressure thresholds at ambient temperature are identified:the synthesis of LuH_(2)from Lu commences at a minimum pressure of~3 GPa,while~28 GPa is the minimum pressure at which LuH_(2)fails to transform into LuH_(3)within a time scale of *** underscores the significant impact of temporal factors on synthesis,with the reaction completion time increasing sub-linearly with rising ***,the cubic phase of LuH_(3)can be obtained exclusively through compressing the trigonal LuH_(3)phase at~11.5 *** also demonstrate that the bandgap of LuH_(3)slowly closes under pressure and is noticeably lower than that of LuH_(2).

关键词： synthesis ambient representing

基于贝叶斯和统计相似度量测的水下自主定位方法

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控制与决策 2025年第1期40卷 48-54页

作者：黄浩乾吕奥奇王迪张昱曈河海大学人工智能与自动化学院江苏常州213000

复杂的水下环境通常会引起信号传播延迟或带来量测野值,从而产生量测丢失和非高斯噪声问题,导致水下自主定位的精度降低.为了解决这些问题,提出一种基于贝叶斯推断和统计相似度量测的水下自主定位方法.首先,该定位方法使用最大后验估计... 详细信息

复杂的水下环境通常会引起信号传播延迟或带来量测野值,从而产生量测丢失和非高斯噪声问题,导致水下自主定位的精度降低.为了解决这些问题,提出一种基于贝叶斯推断和统计相似度量测的水下自主定位方法.首先,该定位方法使用最大后验估计方法来判断量测丢失是否发生.如果接收到此刻的量测信息,则采用不动点迭代方法最大化统计相似度量测的下界,以逼近真实的噪声协方差矩阵,从而获得更准确的状态估计和误差协方差矩阵;如果没有接收到量测信息,则只输出一步预测的状态估计和误差协方差矩阵,以提高该方法的鲁棒性.仿真和海试实验验证结果表明,所提出的水下自主定位方法相较于其他的定位方法具有更高的定位精度和更好的鲁棒性.

关键词：统计相似度量测量测丢失非高斯噪声不动点迭代水下自主定位贝叶斯推断

Analysis of risk factors for bile leakage after laparoscopic exploration and primary suture of common bile duct

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World Journal of Gastrointestinal Surgery 2025年第3期17卷 278-287页

作者： Qing-Song Yang Meng Zhang Chang-Song Ma Da Teng ao Li Ji-Dong Dong Xi-Fei wang Fu-Bao Liu Department of Hepatopancreatobiliary Surgery Affiliated Chuzhou Hospital of Anhui Medical University(The First People’s Hospital of Chuzhou)Chuzhou 239001Anhui ProvinceChina Department of Hepatobiliary and Pancreatic Surgery General SurgeryThe First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina

BACKGROUND Bile leakage is a common complication following laparoscopic common bile duct exploration(LCBDE)with primary duct closure(PDC).Identifying and analyzing the risk factors associated with bile leakage is crucial for improving surgical *** To explore the value analysis of common risk factors for bile leakage after LCBDE and PDC,with a focus on strict adherence to *** Clinical data of 106 cases undergoing LCBDE+PDC in the Hepatobiliary and Pancreatic Surgery Department(Division 1)of Chuzhou First People’s Hospital from April 2019 to March 2024 were *** and multiple factor regression analysis were conducted on common risk factors for bile *** change in surgical time was analyzed using the cumulative summation(CUSUM)method,and the minimum number of cases required to complete the learning curve for PDC was obtained based on the proposed fitting curve by identifying the CUSUM maximum *** Multifactor logistic regression analysis showed that fibrinous inflammation and direct bilirubin/indirect bilirubin were significant independent high-risk factors for postoperative bile leakage(P<0.05).The time to drain removal and length of hospital stay in cases without bile leakage were significantly shorter than in cases with bile leakage(P<0.05),with statistical *** CUSUM method indicated that a minimum of 51 cases were required for the surgeon to complete the learning curve(P=0.023).CONCLUSION With a good assessment of duodenal papilla sphincter function,unobstructed bile-pancreatic duct convergence,exact stone clearance,and sufficient surgical experience to complete the learning curve,PDC remains the preferred method for bile duct closure and is worthy of clinical promotion.

关键词： Laparoscopic common bile duct exploration Primary duct closure Bile leakage Risk factor analysis Cumulative summation