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Development of an Establishment Scheme for a DGVM

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Advances in Atmospheric Sciences 2016年第7期33卷 829-840页

作者： Xiang SONG Xiaodong ZENG Jiawen ZHU pu shao International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of lnformation Science&TechnologyNanjing 210044 University of Chinese Academy of Sciences Beijing 100049

Environmental changes are expected to shift the distribution and abundance of vegetation by determining seedling estab- lishment and success. However, most current ecosystem models only focus on the impacts of abiotic factors on biogeophysics （e.g., global distribution, etc.）, ignoring their roles in the population dynamics （e.g., seedling establishment rate, mortality rate, etc.） of ecological communities. Such neglect may lead to biases in ecosystem population dynamics （such as changes in population density for woody species in forest ecosystems） and characteristics. In the present study, a new establishment scheme for introducing soil water as a function rather than a threshold was developed and validated, using version 1.0 of the IAP-DGVM as a test bed. The results showed that soil water in the establishment scheme had a remarkable influence on forest transition zones. Compared with the original scheme, the new scheme significantly improved simulations of tree population density, especially in the peripheral areas of forests and transition zones. Consequently, biases in forest fractional coverage were reduced in approximately 78.8% of the global grid cells. The global simulated areas of tree, shrub, grass and bare soil performed better, where the relative biases were reduced from 34.3% to 4.8%, from 27.6% to 13.1%, from 55.2% to 9.2%, and from 37.6% to 3.6%, respectively. Furthermore, the new scheme had more reasonable dependencies of plant functional types （PFTs） on mean annual precipitation, and described the correct dominant PFTs in the tropical rainforest peripheral areas of the Amazon and central Africa.

关键词： establishment scheme soil water IAP-DGVM1.0 forest population density fractional coverage

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神经阻滞后反跳痛的研究进展

中国疼痛医学杂志 2024年第6期30卷 453-457页

作者：姚佳惠浦少锋杜冬萍上海交通大学医学院附属第六人民医院疼痛科上海200233

随着超声可视化技术不断地发展,神经阻滞作为一种镇痛技术,广泛地应用于临床麻醉中。传统的以阿片类药物为主的镇痛模式,正在向以外周神经阻滞为主的多模式镇痛转变。全身麻醉复合外周神经阻滞有很多优势,如减少阿片类药物用量,促进病... 详细信息

随着超声可视化技术不断地发展,神经阻滞作为一种镇痛技术,广泛地应用于临床麻醉中。传统的以阿片类药物为主的镇痛模式,正在向以外周神经阻滞为主的多模式镇痛转变。全身麻醉复合外周神经阻滞有很多优势,如减少阿片类药物用量,促进病人早期活动,加快术后康复等。但部分病人在神经阻滞作用消退时发生反跳痛,其表现为难以忍受的剧痛,不仅增加术后镇痛药的使用,而且严重影响着术后恢复。本文旨在探讨神经阻滞后反跳痛的定义、临床表现、危险因素、发生机制以及预防和治疗方法的最新进展,为临床麻醉中合理应用神经阻滞作为辅助镇痛提供指导。

关键词：反跳痛周围神经阻滞区域麻醉术后疼痛

大蒜秸秆对青山羊生长性能、养分表观消化率、血清生化和抗氧化能力的影响

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饲料研究 2024年第7期47卷 7-11页

作者：随韶璞朱广琴迟兰石丰运徐州生物工程职业技术学院江苏徐州221006

试验旨在探讨大蒜秸秆对青山羊血清生化、抗氧化能力、生长性能和养分表观消化率的影响。试验将40只5月龄雄性青山羊按体重相近原则随机分为4组,每组10个重复,每个重复1只羊。对照组饲喂大麦秸秆,试验1组、2组、3组分别用大蒜秸秆替代10... 详细信息

试验旨在探讨大蒜秸秆对青山羊血清生化、抗氧化能力、生长性能和养分表观消化率的影响。试验将40只5月龄雄性青山羊按体重相近原则随机分为4组,每组10个重复,每个重复1只羊。对照组饲喂大麦秸秆,试验1组、2组、3组分别用大蒜秸秆替代10%、20%、30%的大麦秸秆。预试期7 d,正式试验期30 d。结果表明:与对照组相比,试验1组、2组、3组平均日增重较对照组提高了17.7%、29.7%、16.5%(P<0.05),试验2组料重比降低了13.1%(P<0.05);试验1组、2组、3组干物质(DM)、粗蛋白(CP)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)表观消化率均显著提高(P<0.05);试验1组、2组、3组血清中总蛋白含量分别增加3.7%、4.1%、3.4%(P<0.05),白蛋白含量分别增加6.5%、5.2%、2.3%(P<0.05),球蛋白含量分别增加4.1%、3.5%、3.0%(P<0.05),血清中葡萄糖含量分别降低了7.6%、10.2%、6.4%(P<0.05),甘油三酯含量降低了14.3%、23.8%、21.4%。试验1组、2组、3组血清超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、总抗氧化能力(T-AOC)显著高于对照组(P<0.05),试验2组、3组血清谷胱甘肽过氧化物酶(GSH-Px)活性显著高于对照组和试验1组(P<0.05),试验1组、2组、3组血清丙二醛(MDA)显著低于对照组(P<0.05)。研究表明,大蒜秸秆替代部分大麦秸秆饲喂青山羊效果良好,替代20%的大麦秸秆效果最佳。

关键词：大蒜秸秆青山羊生长性能养分表观消化率血清生化指标抗氧化能力

急性氨氮胁迫下大口黑鲈的肝脏转录组特征分析

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水生生物学报 2024年第5期48卷 713-724页

作者：刘品王文博李超严少普李琪罗小敏张硕华张艺琛姚林荣咸阳师范学院生命科学系咸阳712000 西安市水产工作站西安710000

为研究大口黑鲈(Micropterus salmoides)受到氨氮胁迫时基因表达的变化规律,文章采用Illumina平台的HiSeq测序策略分析了氨氮胁迫12h和24h后大口黑鲈肝脏的基因表达谱。氨氮胁迫后在大口黑鲈肝脏共获得111.66 Gb的有效数据,组装获得133... 详细信息

为研究大口黑鲈(Micropterus salmoides)受到氨氮胁迫时基因表达的变化规律,文章采用Illumina平台的HiSeq测序策略分析了氨氮胁迫12h和24h后大口黑鲈肝脏的基因表达谱。氨氮胁迫后在大口黑鲈肝脏共获得111.66 Gb的有效数据,组装获得133486个单基因簇(Unigenes),N50为1000 bp。通过比较转录组分析在2个时间点共获得2072个差异表达基因,其中氨氮胁迫12h获得1516个差异表达基因,907个上调,609个下调;氨氮胁迫24h获得556个差异表达基因,其中330个上调,226个下调。GO功能注释分析结果表明,在氨氮胁迫12h差异基因富集数目明显多于24h,但在“氧化还原酶活性”条目中富集的差异基因数目则是氨氮胁迫24h多于12h。此外,KEGG功能富集分析发现,氨氮胁迫对大口黑鲈肝脏氧化应激、细胞自噬和凋亡相关等途径产生影响。选取10个差异表达基因进行qPCR验证,其表达水平与转录组差异基因分析结果一致,证明了测序结果的可靠性。其中,与氧化应激相关基因缺氧诱导因子1α(HIF1α)、生长停滞DNA损伤可诱导蛋白β(Gadd45β)、DNA损伤诱导转录因子4(DDIT4)、与细胞自噬相关基因自噬微管相关蛋白轻链3(LC3)及与细胞凋亡相关基因下游内质网氧化还原酶1α(Ero1α)在整个胁迫过程中均显著上调。综上所述,氨氮胁迫能引起大口黑鲈肝脏氧化应激,当机体调控作用不足时,大口黑鲈通过细胞自噬与凋亡方式去除受损细胞,以维持内环境稳定。研究结果将为进一步研究大口黑鲈在氨氮胁迫下生理调控的分子机制提供依据。

关键词：氨氮胁迫转录组肝脏大口黑鲈

Reconstruction of summer temperature variation from maximum density of alpine pine during 1917-2002 for west Sichuan Plateau, China

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Journal of Geographical Sciences 2008年第2期18卷 201-210页

作者： WU pu WANG Lily shao Xuemei Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

Having analyzed the tree ring width and maximum latewood density of Pinus densata from west Sichuan, we obtained different climate information from tree-ring width and maximum latewood density chronology. The growth of tree ring width was responded princi- pally to the precipitation in current May, which might be influenced by the activity of southwest monsoon, whereas the maximum latewood density reflected summer temperature （June-September）. According to the correlation relationship, a transfer function had been used to reconstruct summer temperature for the study area. The explained variance of reconstruction is 51% （F=52.099, p〈0.0001）. In the reconstruction series： before the 1930s, the climate was relatively cold, and relatively warm from 1930 to 1960, this trend was in accordance with the cold-warm period of the last 100 years, west Sichuan. Compared with Chengdu, the warming break point in west Sichuan is 3 years ahead of time, indicating that the Tibetan Plateau was more sensitive to temperature change. There was an evident summer warming signal after 1983. Although the last 100-year running average of summer temperature in the 1990s was the maximum, the running average of the early 1990s was below the average line and it was cold summer, but summer drought occurred in the late 1990s.

关键词： west Sichuan （province） plateau tree ring summer temperature

The generation and use of animal models of osteosarcoma in cancer research

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Genes & Diseases 2024年第2期11卷 664-674页

作者： Feifei pu Haoyu Guo Deyao Shi Fengxia Chen Yizhong Peng Xin Huang Jianxiang Liu Zhicai Zhang Zengwu shao Department of Orthopedics Wuhan Hospital of Traditional Chinese and Western Medicine (Wuhan No.1 Hospital)Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430022China Department of Orthopedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430022China Department of Radiation and Medical Oncology Zhongnan HospitalWuhan UniversityWuhanHubei 430071China Hubei Cancer Clinical Study Center Zhongnan HospitalWuhan UniversityWuhanHubei 430071China

Osteosarcoma is the most common malignant bone tumor affecting children and adolescents.Currently,the most common treatment is surgery combined with neoadjuvant chemotherapy.Although the survival rate of patients with osteosarcoma has improved in recent years,it remains poor when the tumor(s)progress and distant metastases develop.Therefore,better animal models that more accurately replicate the natural progression of the disease are needed to develop improved prognostic and diagnostic markers,as well as targeted therapies for both primary and metastatic osteosarcoma.The present review described animal models currently being used in research investigating osteosarcoma,and their characteristics,advantages,and disadvantages.These models may help elucidate the pathogenic mechanism(s)of osteosarcoma and provide evidence to support and develop clinical treatment strategies.

关键词： Animal model Cancer Osteosarcoma Pathogenic mechanism Translational research

Propagation form of internal cracks induced by continuous casting soft reduction and control strategy for internal quality

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Journal of Iron and Steel Research(International) 2024年第3期31卷 622-633页

作者： pu Wang Liang Chen Qun-wei Tang Wei-tao Li shao-xiang Li Jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Weifang Special Steel Group Co..Ltd. Weifang 262400ShandongChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

The propagation form of internal cracks induced by continuous casting soft reduction and the control strategy for enhancing the internal quality of 45 steel through industrial trials and a three-dimensional flow-heat transfer-solidification coupling model were investigated.The results showed that the internal cracks induced by soft reduction exhibited a characteristic of being"coarse in the middle and fine at both ends",and displayed an elliptical arc distribution on the loose side of the strand cross section.The cracks originated within the brittle temperature range and propagated inward to the liquid impenetrable temperature and outward to the zero ductility temperature or below.The control strategy for enhancing the internal quality of the 45 steel strand through soft reduction is to adjust the casting speed or the reduction zone appropriately,ensuring that the central solid fraction of the reduction zone falls within the range of 0.33-0.99.At this point,a reasonable reduction amount is allocated to eliminate the center shrinkage cavities and center segregation,even if it results in minor reduction-induced cracks.

关键词： Continuous casting Soft reduction Crack propagation Internal quality Control strategy

Bifurcations and the penetrating rate analysis of a model for percussive drilling

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Acta Mechanica Sinica 2010年第3期26卷 467-475页

作者： Qing-Jie Cao Marian Wiercigroch Ekaterina Pavlovskaia shao-pu Yang Centre for Nonlinear Dynamics Research Shijiazhuang Railway Institute Shijiazhuang 050043 China School of Astronautics Haerbin Institute of Technology Haerbin 150001 China Department of Engineering Centre for Applied Dynamics Research King's College University of Aberdeen Aberdeen AB24 3UE Scotland UK

In this paper, we investigate a low dimensional model of percussive drilling with vibro-impact to mimic the nonlinear dynamics of the bounded progression. Non- holonomity which arises in the stick-slip caused by the impact during drilling fails to be correctly identified via the classical techniques. A reduced model without non-holono- mity is derived by the introduction of a new state variable, of which averaging technique is employed successfully to detect the periodic motions. Local bifurcations are presented directly by using C-L method. Numerical simulations and the penetrating rate analysis along different choices of parame- ters have been carried out to probe the nonlinear behaviour and the optimal penetrating rate of the drilling system.

关键词： Bifurcation Chaos Non-holonomity Percussive drilling

Contact Behavior of Worn Bearings with Elastoplastic Functionally Graded Coating Based on Mixed Elastohydrodynamic Lubrication

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Acta Mechanica Solida Sinica 2021年第1期34卷 124-136页

作者： Xue-Qian Fang Yao Ning shao-pu Yang Hai-Hua Wang State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang050043China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang050043China Hebei Key Laboratory for Mechanics of Smart Materials and Structures Shijiazhuang050043China School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang050043China

The dynamic contact behavior of worn bearings with elastoplastic functionally graded coating is studied,and the interacting effect between worn band and functionally graded surface is analyzed.The surface deformation and roughness are included in the film thickness.The mixed elastohydrodynamic lubrication combined with point contact model is introduced to analyze the oil pressure in the contact zone.By using the Fourier transform method and Papkovich-Neuber potential function,the displacements and stress fields in the elastoplastic functionally graded coating are obtained.The second-order central difference method is used to solve the Reynolds equation.It is found that the repeated surface interaction can result in the sharp increase in pressure in bearings,and the oil pressure increases with increasing graded index.The entrainment of oil in the inlet and outlet zones becomes more evident if a large graded index is selected.

关键词： Wear bearings Contact behavior Elastoplastic functionally graded surface Mixed elastohydrodynamic lubrication.Central difference method