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A Semi-Analytical Method for the PDFs of A Ship Rolling in Random Oblique Waves

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China Ocean Engineering 2018年第1期32卷 74-84页

作者： liU li-qin liU Ya-liu XU Wan-hai li Yan TANG you-gang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University

The PDFs(probability density functions) and probability of a ship rolling under the random parametric and forced excitations were studied by a semi-analytical method. The rolling motion equation of the ship in random oblique waves was established. The righting arm obtained by the numerical simulation was approximately fitted by an analytical function. The irregular waves were decomposed into two Gauss stationary random processes, and the CARMA(2, 1) model was used to fit the spectral density function of parametric and forced excitations. The stochastic energy envelope averaging method was used to solve the PDFs and the probability. The validity of the semi-analytical method was verified by the Monte Carlo method. The C11 ship was taken as an example, and the influences of the system parameters on the PDFs and probability were analyzed. The results show that the probability of ship rolling is affected by the characteristic wave height, wave length, and the heading angle. In order to provide proper advice for the ship’s manoeuvring, the parametric excitations should be considered appropriately when the ship navigates in the oblique seas.

关键词： ship random rolling parametric and forced excitations stochastic energy envelope averaging method probability density function parameter influence analysis

传统与现代健身运动——太极拳与健美操的对比

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四川体育科学 2004年第3期23卷 116-118页

作者：潜沉香杨锋李庆友华中师范大学体育系湖北武汉430079

健美操和太极拳运动作为学校强身健体的重要教学内容和手段之一,在各高校已蓬勃开展。通过对这两项运动的共性和个性进行探讨,使学生正确认识两者之间的关系,更好地合理安排、选择自己所喜受的运动项目,以培养持久的兴趣,真正为实现终... 详细信息

健美操和太极拳运动作为学校强身健体的重要教学内容和手段之一,在各高校已蓬勃开展。通过对这两项运动的共性和个性进行探讨,使学生正确认识两者之间的关系,更好地合理安排、选择自己所喜受的运动项目,以培养持久的兴趣,真正为实现终身体育打下基础。

关键词：健身运动太极拳健美操对比研究终身体育教学内容教学手段

HMFI分子筛Bronsted酸性位点与碱性分子的作用机制

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原子与分子物理学报 2025年第4期42卷 1-7页

作者：郑健秦康秦玉才宋丽娟中石化石油化工科学研究院有限公司北京100083 辽宁石油化工大学辽宁省石油化工催化科学与技术重点实验室抚顺113001

采用密度泛函理论(DFT)方法,以单铝、双铝和三铝酸性位点HMFI分子筛为模型分子筛,计算去质子化能考察HMFI分子筛的本征酸性,以NH_(3)分子作为模型分子,计算NH_(3)分子在HMFI分子筛中的吸附能与去质子化能进行关联性分析,并进一步考察NH_... 详细信息

采用密度泛函理论(DFT)方法,以单铝、双铝和三铝酸性位点HMFI分子筛为模型分子筛,计算去质子化能考察HMFI分子筛的本征酸性,以NH_(3)分子作为模型分子,计算NH_(3)分子在HMFI分子筛中的吸附能与去质子化能进行关联性分析,并进一步考察NH_(3)分子与HMFI分子筛的作用机制.研究表明分子筛Bronsted酸(简称B酸)强度与B酸数量没有强相关性,在考虑B酸位数量的同时须考虑B酸位的分布.酸性位点数量和分布的差异均可以调控NH_(3)分子的吸附构象,并且可以通过调节HMFI分子筛孔道对分子施加相互作用的模式,解析分子的结构和电子性质,精准调控分子的进一步转化.此项工作可以为未来高效多孔材料有效物种活性位的构建提供新思路.

关键词：密度泛函理论 HMFI分子筛 Bronsted酸性质吸附性能

Enantioselective Construction of Polycyclic Chromanes through Organocatalytic Sequential Quintuple Reaction via One-Pot Step-Wise Procedure

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Chinese Journal of Chemistry 2024年第18期42卷 2197-2202页

作者： Jie Wang Hang qin Ya-li Song Fei Cao Zhi-Hao you Key Laboratory of Pharmaceutical Quality Controlof Hebei Province College of Pharmaceutical SciencesHebei UniversityBaodingHebei 071002China Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education BaodingHebei 071002China

An efficient and highly stereoselective synthetic method to access polycyclic chromanes has been achieved through organocatalyzed one-pot step-wise reactions involving 2-hydroxycinnamaldehydes,2-aminochalcones,and malononitrile as *** reactions underwent a quintuple process by aza-Michael/Michael/Knoevenagel/oxa-Michael/aldol-type reaction in sequence to give products bearing 3 new generated rings and 5 chiral centers in moderate to quantitative yields with excellent stereoselectivities.

关键词： Asymmetric catalysis Organocatalysis Cyclization Quintuple reaction Polycycles Heterocycles Chromane One-pot reaction

The conformity of HI galaxies in ALFALFA-SDSS sample

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Research in Astronomy and Astrophysics 2021年第2期21卷 61-67页

作者： lin-Cheng li Bo qin Jie Wang Jing Wang you-Gang Wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China International Centre for Radio Astronomy Research(ICRAR) The University of Western Australia35 Stirling HwyCrawleyWA6009Australia Department of Astronomy Peking UniversityBeijing 100871China

The conformity effect,indicating the evolution of galaxies is related to its surrounding neighbor galaxies as far as a few Mpc,is an interesting phenomenon in the modeling of galaxy and *** we study the conformity effect of HI galaxies in a matched galaxy sample between SDSS DR7 and ALFALFA *** checking the probability difference for the detected H i galaxies as a function of distance around a normal or an H i galaxy,we find that this effect is significant out to 5 *** also shows a dependence on the stellar mass of galaxies,with the strength the strongest in the stellar mass range of 10^(10)light on the co-evolution of the galaxies and their neighbors in the current galaxy formation models.

关键词： method data analysis-radio lines galaxies-galaxies evolution

Myosin regulates intracellular force and guides collective cancer cell migration via the FAK-Rho/ROCK feedback loop

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Genes & Diseases 2023年第6期10卷 2199-2201页

作者： Xiang qin Yuchen He Yixi Zhang Shun li Tingting li Fengming you Yiyao liu Department of Pharmacy Personalized Drug Therapy Key Laboratory of Sichuan ProvinceSichuan Provincial People's HospitalSchool of Life Science and TechnologyUniversity of Electronic Science and Technology of ChinaChengduSichuan 611731China TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province Hospital of Chengdu University of Traditional Chinese MedicineChengduSichuan 610072China

Breast cancerhas been one of the biggest killers of women due to its susceptibility and high *** observations show that malignant cancer cells frequently invade the surrounding normal tissue in collective rather than individual cell migration.1,2 For individual cell migration,it has been found that the Rho/ROCK signaling is upregulated and correlates with disease progression.3 Meanwhile,Rho activates myosin-ll and the actomyosin-mediated contraction creates tension within the cells.4,5 However,the roles of the activation of the Rho/RoCK signal pathway in collective cell migration and the precise mechanisms by which myosin-ll fine-tunes the contractility of the cells to allow for the reorganization of the cytoskeleton that drives collective cell migration,remain *** study investigated whether the high cellular contractility could activate the inside-out signal transductions and how did the intracellular force contribute to the collective cell migration.

关键词： cancer collective migration

Efficacy of Chinese Medicine Acupoint Application Combined with Montelukast on Children with Perennial Allergic Rhinitis:A Randomized Controlled Trial

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Chinese Journal of Integrative Medicine 2020年第11期26卷 845-852页

作者： li you-jin ZONG Ming DING li-feng RUI Xiao-qing MA Bei-yin qin li-ping Department of Otorhinolaryngology-Head and Neck Surgery Shanghai Children's Medical CenterShanghai Jiaotong University School of MedicineShanghai(200127)China Department of Clinical Laboratory Shanghai East HospitalSchool of MedicineTong Ji UniversityShanghai(200120)China Department of Chinese Medicine Shanghai Children's Medical CenterShanghai Jiaotong University School of MedicineShanghai(200127)China Department of Medical Genetics and Molecular Diagnostic Laboratory Shanghai Children's Medical CenterShanghai Jiaotong University School of MedicineShanghai(200127)China Department of Chinese Medicine Xinhua HospitalShanghai』aotong University School of MedicineShanghai(200090)China

Objective To evaluate the efficacy of Chinese medicine acupoint application(CMAA)combined with Western medicine for perennial allergic rhinitis(PAR)in *** In this prospective,parallel,randomized,placebo-controlled and single-blind trial from August to September,2017,180 children with PAR were randomly assigned to an integrative group(CMAA and Montelukast),CMAA group(CMAA and placebo tablet),or Montelukast group(placebo CMAA and Montelukast).Participants were applied with CMAA for 6 sessions over 2 weeks,and/or Montelukast Chewable Tablet orally once daily for 12 *** changes in severity of symptoms were measured by Visual Analog Scale(VAS)and rhinitis control assessment test(RCAT)at 0,2,4 and 12 weeks of *** samples were collected for serum interleukin-4,interferon gammaγand T helper type 1(Th1)/Th2 flow cytometric analysis at the time points of 0,4 and 12 *** Eight cases dropped out from the trial,3 in the integrative group,2 in the CMAA group and 3 in the Montelukast *** VAS scores decreased significantly while the RCAT scores increased significantly in all three groups at 4 and 12 weeks compared with baseline(Pline(Plinical Trial Register,registration ***-IOR-17012434).

关键词： allergic rhinitis Chinese medicine acupoint application Montelukast interferon gamma/interleukin-4 T helper type 1/T helper type 2

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钢轨“高点”缺陷分析与控制

轧钢 2015年第2期32卷 85-89页

作者：陶功明吕攀峰李佑琴朱华林范红平攀钢集团攀枝花钢钒有限公司四川攀枝花617062

钢轨通长方向上局部轨高异常偏高称为"高点"。"高点"严重影响高速列车的运行安全,是高速铁路用钢轨突出且难解决的质量缺陷。本文就重轨连轧过程中存在的"高点"问题进行了分析,认为轧件脱离轧辊时的瞬间"甩尾"是"高点"形成的根本原因。... 详细信息

钢轨通长方向上局部轨高异常偏高称为"高点"。"高点"严重影响高速列车的运行安全,是高速铁路用钢轨突出且难解决的质量缺陷。本文就重轨连轧过程中存在的"高点"问题进行了分析,认为轧件脱离轧辊时的瞬间"甩尾"是"高点"形成的根本原因。为止,提出并验证了控制连轧张力、调整出钢侧导板间隙、增加连轧轧制道次、优化头底延伸系数等减轻或消除"高点"的措施。上述方法中单机架完成钢轨成品道次轧制是可靠而稳定的方法,可使轨高"高点"稳定控制在0.2mm以下。

关键词：钢轨 “高点”缺陷甩尾仿真分析轧机布置

Characterization of the Promoter of a Homolog of Maize MADS-Box Gene m18

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Journal of Integrative Agriculture 2014年第11期13卷 2330-2345页

作者： qin Hui-juan PAN Hong FAN Xian-wei WU Qiao li you-zhi Key Laboratory for Microbial and Plant Genetic Engineering Ministry of Education/State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Ministry of Science and Technology/College of Life Science and Technology Guangxi University

Maize （Zea mays L.） is one of the world’s major food crops, and often suffers from tremendous yield loss caused by abiotic stresses. The MADS-box genes are known to play versatile roles in plants, controlling plant responses to multiple abiotic stresses. However, understanding of regulation of their expressions by the conventional loss-of-function approach is very dififcult. So far, regulation of MADS-box gene expression is little known. The best approach to retrieve expression regulation of this category of genes is to characterize expression of their promoters. In this study, the promoter of a homolog （GenBank accession no. EC864166） of maize MADS-box gene m18 was cloned by way of genome-walking PCR, named Pro66. Predicative analysis indicated that Pro66 contains more than one TATA box and multiple cis-acting environmental conditions-responsive elements （ECREs）. Pro66 could drive expression of theβ-glucuronidase （GUS）-encoding gene in maize, and heterologous expression of GUS in red pepper stressed by water deifcit, salt, copper, iron deifciency, heat, cold, and grown under short and long photoperiods, echoing predicative ECREs. Conclusively, maize MADS-box gene m18 likely plays versatile functions in maize response to multiple abiotic stresses due to the promoter with multiple cis-acting elements. The complex arrangement of multiple cis-acting elements in the promoter features meticulously regulated expression of m18. The results give informative clues for heterologous utilisation of the promoters in monocot and dicot species. The copy of the ECREs and heterologous expression of the promoter in dicot species are also discussed.

关键词： maize MADS-box gene promoter stress transcription