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Molecular Grouping of Grateloupia Tissues Collected Along Chinese Coast and Microsatellite Diversity Analysis of G. asiatica

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Journal of Ocean University of China 2018年第4期17卷 925-931页

作者： peng chong DING Haiyan TANG Zhihong GUO Li YANG Guanpin College of Marine Life Sciences Ocean University of China Institute of Evolution & Marine Biodiversity Ocean University of China Key Laboratory of Marine Genetics and Breeding of Chinese Ministry of Education Ocean University of China

Genus Grateloupia is one of the most speciose genera in family Halymeniales. It is also one of the sources for natural materials, food and medicine. With different environments, Grateloupia change their morphological characteristics, making their morphological identification very difficult. In addition, few of the species diversity in this genus has been described before. In this study, phylogenetic analysis based on rbc L gene sequence was employed to group Grateloupia collected from three locations along Chinese coast. The microsatellites were also used to evaluate their genetic diversity. In total, the tissue parts of 6 putative species were collected from G. asiatica, G. livida, G. lanceolate, G. catenata, G. turuturu and G. filicina. In order to evaluate their genetic diversity and then conserve them better, 40 microsatellites available for Grateloupia were used to evaluate their genetic diversity, and 11 microsatellites were found to be applicable to determine the genetic diversity of G. asiatica. It was found that the genetic diversity of G. asiatica around Qingdao was very rich. We suggested that the species of genus Grateloupia should be identified based on rbc L phylogenetic analysis before the diversity evaluation with microsatellites. The microsatellites should be developed for each species of Grateloupia so that their genetic diversity can be evaluated appropriately.

关键词： Grateloupia rbc L molecular grouping microsatellite genetic diversity

Review of Sc microalloying effects in Al-Cu alloys

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1098-1114页

作者： Shenghua Wu chong Yang peng Zhang Hang Xue Yihan Gao Yuqing Wang Ruihong Wang Jinyu Zhang Gang Liu Jun Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China School of Aerospace Engineering North University of ChinaTaiyuan 030051China

Artificially controlling the solid-state precipitation in aluminum (Al) alloys is an efficient way to achieve well-performed properties,and the microalloying strategy is the most frequently adopted method for such a purpose.In this paper,recent advances in lengthscale-dependent scandium (Sc) microalloying effects in Al-Cu model alloys are reviewed.In coarse-grained Al-Cu alloys,the Sc-aided Cu/Sc/vacancies complexes that act as heterogeneous nuclei and Sc segregation at the θ′-Al_(2)Cu/matrix interface that reduces interfacial energy contribute significantly to θ′precipitation.By grain size refinement to the fine/ultrafine-grained scale,the strongly bonded Cu/Sc/vacancies complexes inhibit Cu and vacancy diffusing toward grain boundaries,promoting the desired intragranular θ′precipitation.At nanocrystalline scale,the applied high strain producing high-density vacancies results in the formation of a large quantity of (Cu Sc,vacancy)-rich atomic complexes with high thermal stability,outstandingly improving the strength/ductility synergy and preventing the intractable low-temperature precipitation.This review recommends the use of microalloying technology to modify the precipitation behaviors toward better combined mechanical properties and thermal stability in Al alloys.

关键词： aluminum alloy microalloying effect length-scale dependence precipitation mechanical properties

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基于局部相似性学习的鲁棒非负矩阵分解

数据采集与处理 2023年第5期38卷 1125-1141页

作者：侯兴荣彭冲青岛大学计算机科学技术学院青岛266071

现有的非负矩阵分解方法往往聚焦于数据全局结构信息的学习,在很多情况下忽略了对数据局部信息的学习,而局部学习的方法也通常局限于流行学习,存在一些缺陷。为解决这一问题,提出了一种基于数据局部相似性学习的鲁棒非负矩阵分解算法(Ro... 详细信息

现有的非负矩阵分解方法往往聚焦于数据全局结构信息的学习,在很多情况下忽略了对数据局部信息的学习,而局部学习的方法也通常局限于流行学习,存在一些缺陷。为解决这一问题,提出了一种基于数据局部相似性学习的鲁棒非负矩阵分解算法(Robust nonnegative matrix factorization with local similarity learning,RLS-NMF)。采用一种新的数据局部相似性学习方法,它与流形方法存在显著区别,能够同时学习数据的全局结构信息,从而能挖掘数据类内相似和类间相离的性质。同时,考虑到现实应用中的数据存在异常值和噪声,该算法还使用l_(2,1)范数拟合特征残差,过滤冗余的噪声信息,保证了算法的鲁棒性。多个基准数据集上的实验结果显示了该算法的最优性能,进一步证明了该算法的有效性。

关键词：非负矩阵分解聚类全局结构局部相似性鲁棒性

Molecular phylogenetic relationships based on mitochondrial genomes of novel deep-sea corals(Octocorallia:Alcyonacea):Insights into slow evolution and adaptation to extreme deep-sea environments

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Zoological Research 2024年第1期45卷 215-225页

作者： Zhan-Fei Wei Kai-Wen Ta Nan-Nan Zhang Shan-Shan Liu Liang Meng Kai-Qiang Liu chong-Yang Cai Xiao-Tong peng Chang-Wei Shao National Key Laboratory of Mariculture Biobreeding and Sustainable Goods Yellow Sea Fisheries Research InstituteChinese Academy of Fishery SciencesQingdaoShandong 266071China BGI-Qingdao BGI-ShenzhenQingdaoShandong 266555China Institute of Deep-Sea Science and Engineering Chinese Academy of SciencesSanyaHainan 572000China

A total of 10 specimens of Alcyonacea corals were collected at depths ranging from 905 m to 1633 m by the manned submersible Shenhai Yongshi during two cruises in the South China Sea(SCS).Based on mitochondrial genomic characteristics,morphological examination,and sclerite scanning electron microscopy,the samples were categorized into four suborders(Calcaxonia,Holaxonia,Scleraxonia,and Stolonifera),and identified as 9 possible new cold-water coral species.Assessments of GC-skew dissimilarity,phylogenetic distance,and average nucleotide identity(ANI)revealed a slow evolutionary rate for the octocoral mitochondrial sequences.The nonsynonymous(Ka)to synonymous(Ks)substitution ratio(Ka/Ks)suggested that the 14 protein-coding genes(PCGs)were under purifying selection,likely due to specific deep-sea environmental pressures.Correlation analysis of the median Ka/Ks values of five gene families and environmental factors indicated that the genes encoding cytochrome b(cyt b)and DNA mismatch repair protein(mutS)may be influenced by environmental factors in the context of deep-sea species formation.This study highlights the slow evolutionary pace and adaptive mechanisms of deep-sea corals.

关键词： Mitochondrial genome Alcyonacea Ka/Ks evolution Environmental factors

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消费型街道:道路密度与消费活力的微观证据

经济学（季刊） 2022年第4期22卷 1361-1382页

作者：彭冲金培振南京审计大学经济学院上海交通大学中国发展研究院华东师范大学经济学院 200062

本文利用大数据挖掘技术、地理信息技术构建上海的网格化数据集,实证检验街区层面的道路密度对消费活力的影响。研究发现,更高的路网密度提升了服务消费的数量、质量和多样性,等级低的路网其密度越高越有利于消费活力的提升,上述效应呈... 详细信息

本文利用大数据挖掘技术、地理信息技术构建上海的网格化数据集,实证检验街区层面的道路密度对消费活力的影响。研究发现,更高的路网密度提升了服务消费的数量、质量和多样性,等级低的路网其密度越高越有利于消费活力的提升,上述效应呈现显著的“中心-外围”特征。机制分析表明,提升道路连通性通过影响人流量增强消费活力,这种机制在等级低、步行友好的道路中更加显著。进一步分析显示,消费活力会资本化到房价和住宅租金中。

关键词：路网密度消费活力大数据

Using Multi-agent System for Residential Expansion Models——A Case Study of Hongshan District,Wuhan City

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Chinese Geographical Science 2007年第3期17卷 210-215页

作者： peng chong &Email:pengchong1980@*** Cheng Jianquan Department of Urban Resources Sciences Nanjing University Nanjing 210093 China Department of Environmental & Geographical Sciences Manchester Metropolitan University M1 5GD UK

Residential expansion is gaining more and more attention from government authorities and urban planners.However,most of the current urban models focus heavily on presenting economic,political and ecological objectives of urban development,while seldom taking the effects of human behavior into consideration.Multi-agent systems for land use/cover change(MAS/LUCC),which mainly concern the behavioral effects of stakeholders on the processes of land use/cover change,are promising to fill the gap.This article,based on the concepts of MAS/LUCC model,con-structs a multi-agent system for residential expansion model(MAS/RE)through the analysis of the behavior of gov-ernment authorities and households.The model takes complex human actions into account,namely urban master plan-ning,planning review and approval,policies of traffic,economy and environment,location and allocation choices of the households and their interrelationships.Taking Hongshan District of Wuhan City,Hubei Province as an illustration,the model is implemented on Arc/info platform to simulate residential expansion between 1996 and 2002.The study result shows that the model is suitable for understanding the process of residential expansion with the effects of human actions,and is especially effective for its capacity in presenting spatio-temporal and behavioral complexity.Therefore,the model can be a reference for policy-making for government authorities and urban planners.

关键词：中国武汉住宅扩张 GIS 区位选择

Clinicopathological significance and immunotherapeutic outcome of claudin 18.2 expression in advanced gastric cancer:A retrospective study

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Chinese Journal of Cancer Research 2024年第1期36卷 78-89页

作者： Changsong Qi Xiaoyi chong Ting Zhou Mingyang Ma Jifang Gong Miao Zhang Jian Li Jun Xiao Xiaohui peng Zhen Liu Zonghai Li Lin Shen Xiaotian Zhang State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers Beijing Key Laboratory of Carcinogenesis and Translational ResearchDepartment of Gastrointestinal OncologyPeking University Cancer Hospital&InstituteBeijing 100142China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of Gastrointestinal OncologyPeking University Cancer Hospital&InstituteBeijing 100142China CARsgen Therapeutics Co. LtdShanghai 200231China CARsgen Life Sciences Co. LtdShanghai 200131China

Objective: Immunotherapeutic outcomes and clinical characteristics of claudin 18 isoform 2 positive(CLDN18.2-positive) gastric cancer(GC) vary in different clinical studies, making it difficult to optimize antiCLDN18.2 therapy. We conducted a retrospective analysis to explore the association of CLDN18.2 expression with clinicopathological characteristics and immunotherapeutic outcomes in GC.Methods: A total of 536 advanced GC patients from 2019 to 2021 in the CT041-CG4006 and CT041-ST-01clinical trials were included in the analysis. CLDN18.2 expression on ≥40% of tumor cells(2+, 40%) and CLDN18.2 expression on ≥70% of tumor cells(2+, 70%) were considered the two levels of positively expressed GC. The clinicopathological characteristics and immunotherapy outcomes of GC patients were analyzed according to CLDN18.2 expression status.Results: CLDN18.2 was expressed in 57.6%(cut-off: 2+, 40%) and 48.9%(cut-off: 2+, 70%) of patients.Programmed death-ligand 1(PD-L1) and CLDN18.2 were co-expressed in 19.8% [combined positive score(CPS)≥1, CLDN18.2(cut-off: 2+, 40%)] and 17.2% [CPS≥5, CLDN18.2(cut-off: 2+, 70%)] of patients.CLDN18.2 expression positively correlated with younger age, female sex, non-gastroesophageal junction(nonGEJ), and diffuse phenotype(P<0.001). HER2 and PD-L1 expression were significantly lower in CLDN18.2-positive GC(both P<0.05). Uterine adnexa metastasis(P<0.001) was more frequent and liver metastasis(P<0.001)was less common in CLDN18.2-positive GC. Overall survival and immunotherapy-related progression-free survival(ir PFS) were inferior in the CLDN18.2-positive group.Conclusions: CLDN18.2-positive GC is associated with poor prognosis and worse immunotherapeutic outcomes. The combination of anti-CLDN18.2 therapy, anti-PD-L1/PD-1 therapy, and chemotherapy for GC requires further investigation.

关键词： Gastric cancer claudin18.2 CT041 PD-L1 immunotherapy

河南一次罕见飞机积冰过程云系宏微观特性的综合观测

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大气科学 2023年第6期47卷 1757-1769页

作者：彭冲宋灿蔡淼河南省人工影响天气中心郑州450003 中国气象局云雾物理环境重点开放实验室北京100081 中国气象局河南省农业气象保障与应用技术重点实验室郑州450003 中国气象局人工影响天气中心北京100081

2018年12月10日河南省人工影响天气中心探测到本省飞机增雨有史以来的最强积冰,积冰出现高度为3600 m(−7.9℃~−12.9℃),机头及机翼最厚积冰达到16.2 cm。利用机载DMT云物理探测资料,结合FY-4A卫星反演云参数和雷达等综合观测,对本次过... 详细信息

2018年12月10日河南省人工影响天气中心探测到本省飞机增雨有史以来的最强积冰,积冰出现高度为3600 m(−7.9℃~−12.9℃),机头及机翼最厚积冰达到16.2 cm。利用机载DMT云物理探测资料,结合FY-4A卫星反演云参数和雷达等综合观测,对本次过程的云宏、微观结构特征进行了细致分析。结果表明,此次过程强积冰区域位于700 hPa切变线东侧附近,西南急流持续输送水汽,且大气有深厚逆温层存在,有利于水汽和液态水的堆积。产生积冰的云系云顶高度约4000~5000 m,云顶温度为−15℃~−20℃,云光学厚度大于30。FY-4A云顶相态与机载仪器观测结果较为一致,对过冷水和飞机积冰区域具有一定指示意义。强积冰区域液态水含量丰沛,最大液态含水量可达0.818 g m^(−3),大量球型过冷液滴和半径超过50μm的过冷大滴存在是导致积冰的重要原因。由于强积冰区域缺少尺度超过毫米量级的冰晶粒子,其S波段天气雷达回波值较弱,甚至明显低于非积冰区域。因此在使用天气雷达监测时,单靠回波强度来判断积冰强度存在一定的局限性。

关键词：飞机积冰 FY-4A卫星机载探测云宏微观特性

Study on Relationship between Microstructure of Active Phase and HDS Performance of Sulfided Ni-Mo Catalysts: Effect of Metal Loading

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China Petroleum Processing & Petrochemical Technology 2014年第2期16卷 12-19页

作者： Guo Rong Shen Benxian Fang Xiangchen Sun Jin peng chong Cui Xiaoli State Key Laboratory of Chemical Engineering East China University of Science and Technology Fushun Research Institute of Petroleum and Petrochemicals SINOPEC

Six Ni-Mo catalysts with different metal contents were prepared and characterized by N2 adsorption and X-ray diffractometry. The active phase microstructure of these catalysts was examined by the Raman spectroscopy, temperatureprogrammed reduction(TPR), X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. Hydrodesulfurization(HDS) activity of catalyst samples were analyzed in a flow fixed-bed microreactor. The sulfidation degree of Mo and the length of the MoS2 slab slightly increased with the amount of metal loaded following sulfidation. This small change is attributed to polymolybdate species observed in all the oxidized catalysts. Weak metal-support interactions, as determined by the TPR technique, increased the NiSx sulfidation phase and MoS2 slab stacking. The HDS activity of the catalyst samples increased with the number of active sites. For high metal loading catalysts, their HDS activity was nearly identical because the sulfur atoms cannot easily approach active sites. This change is caused by the large number of stacked layers in the MoS2 slabs as well as the decrease in the specific surface area and pore volume of the catalyst samples with an increasing metal loading.

关键词：加氢脱硫活性镍钼催化剂二硫化钼金属含量微观结构脱硫性能研究活动 X射线光电子能谱