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Theoretical Solutions of Dynamic Responses of Cancellous Bone

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Journal of Biosciences and Medicines 2019年第12期7卷 156-167页

Human bone may be damaged by impact in the cases of traffic accidents and ship impact. The impact responses of cancellous bone were analyzed based on the two-phase media theory. A direct analytical method is introduced for solving this type of problems. First, flow function and potential function were introduced to decouple the controlling equations. Then direction solving method was used to obtain the solution. The solution is determined by the parameters of a (related with wave speed) and b (related with damping), as well as the boundary conditions. These two parameters a and b determine the propagation speed of the responses along the bone and the attenuation rate. It is shown that the responses: deformation, stress and pressure of the corpus medullae caused by loading, propagate toward the other end when the impact is acted on one end of the bone. The responses are discontinuous during propagate. The discontinuous surface moves with a constant speed. The responses at the cross section increase gradually from the bottom to the top because of the distribution of the loading at the boundary. The solutions can be used as the basis for certification of numerical simulation as well as the design of impact prevention of bone.

关键词： Cancellous Bone Impact Load Responses Decoupling Method

Study on the Classification of Pulse Signal Based on the BP Neural Network

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Journal of Biosciences and Medicines 2020年第5期8卷 104-112页

The objectification of the pulse signal analysis is a practical problem. The classification of the pulse signal is studied based on the BP neural network. It is first analyzed how to select the characteristic factors of the pulse signal. Then the method of nondimensionalization/normalization on the pulse signal is presented to preprocess the characteristic factors. The classification of the pulse signal and the effects of the selection of characteristic factors are studied by using the normalized data and BP neural network. It is shown that nondimensionalization/normalization of the data is in favor of the training and forecasting of the network. The selection of characteristic factors affects the accuracy of forecasting obviously. The results of forecasting by selection of 8, 6 and 4 factors respectively show that the less the factors are, the worse the effects are.

关键词： BP Neural Network Pulse Signal Classification Dimensional Analysis

Characteristic Rainfall for Warning of Debris Flows

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Journal of Mountain Science 2010年第3期7卷 207-214页

作者： HU Kaiheng Cui Peng Wang Chuanchang Li Yong lu xiaobing Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences & Ministry of Water Conservancy Chengdu 610041 China Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

A characteristic rainfall is introduced to overcome the difficulties encountered in determining a critical rainfall value for triggering debris *** characteristic value is defined as the rainfall at which debris-flow occurrence probability shows a rapid increase,and can be used as a warning rainfall threshold for debris *** of recorded debris flows and 24-hour rainfall data at Jiangjia basin,Yunnan Province,in southwestern China,demonstrates the existence of such a characteristic *** was found that the characteristic rainfall corresponds to the daily rainfall of 90% cumulative probability by analyzing the basin's daily rainfall *** result provides a simple and useful method for estimating a debris-flow warning rainfall threshold from the daily rainfall *** was applied to estimate the debris-flow warning rainfall threshold for the Subaohe basin,a watershed in the 2008 Wenchuan earthquake zone with many physical characteristics similar to those of the Jiangjia basin.

关键词： Debris flow Wenchuan earthquake warning rainfall threshold statistics of daily rainfalldistribution

Advances in the prerequisite and consequence of STING downstream signalosomes

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Medical Review 2024年第5期4卷 435-451页

作者： Xinliang lu xiaobing Li Lili Li Chuanhui Han Sirui Li Institute of Immunology and Bone Marrow Transplantation Center of the First Affiliated Hospital Zhejiang University School of MedicineHangzhouChina InvivoGen Ltd. Hong Kong Science and Technology ParksHong KongChina Center for Systems Medicine Institute of Basic Medical SciencesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Suzhou Institute of Systems Medicine SuzhouJiangsuChina Peking University International Cancer Institute Peking University Cancer Hospital and InstituteHealth Science CenterPeking UniversityBeijing100084China Lineberger Comprehensive Cancer Center University of North Carolina at Chapel HillChapel HillNC 27599USA

The cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING)pathway is an evolving DNA-sensing mechanism involved in innate immunity and pathogen defense that has been optimized while remaining *** from recognizing pathogens through conserved motifs,these receptors also detect aberrant or misplaced self-molecules as possible signs of perturbed *** binding external or self-derived DNA,a mobile sec-ondary messenger 2′3′-cyclic GMP-AMP(cGAMP)is produced by cGAS and in turn activates its adapter STING in the endo-plasmic reticulum(ER).Resting-state or activated STING protein isﬁnely restricted by multiple degradation *** post-translational changes of the STING protein,along with the regulatory machinery ofthe secret routes,limit the onset,strength and sustention of STING *** experiences a conformational shift and relocates with TBK1 from the ER to perinuclear vesicles containing transcription factors,provoking the transcription activity of IRF3/IFN-I and NF-κB pathways,as well as to initiate a number of cellular processes that have been shown to alter the immune landscape in cancer,such as autophagy,NLRP3 inflamma-some,ER stress,and cell *** signal thus serves as a potent activator for immune mobilization yet also triggers immune-mediated pathology in *** advances have established the vital role of STING in immune surveil-lance as well as tumorigenic *** review provides an overview of the disparate outcomes of cancer attributed to the actions of pleiotropic and coordinated STING downstream signalosomes,along with the underlying mechanisms of STING function in pathologies,providing therapeutic impli-cations for new approaches in hunt for the next generation of cancer immunotherapy base on STING.

关键词： stimulator of interferon genes signalosomes cellular heterogeneity cancer therapeutics

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高速铁路受电弓主动控制算法适用性研究

西南交通大学学报 2015年第2期50卷 233-240页

作者：鲁小兵刘志刚西南交通大学电气工程学院四川成都610031

为分析适用于不同受电弓的最佳主动控制算法,建立了有效的弓网模型,设计了最优控制器、变结构控制器和模糊控制器.以应用最广泛的SBS81、DSA250、DSA380和SSS400+型受电弓为控制对象进行了验证,并分析了控制前后接触力最大值、最小值、... 详细信息

为分析适用于不同受电弓的最佳主动控制算法,建立了有效的弓网模型,设计了最优控制器、变结构控制器和模糊控制器.以应用最广泛的SBS81、DSA250、DSA380和SSS400+型受电弓为控制对象进行了验证,并分析了控制前后接触力最大值、最小值、平均值和标准差4个统计量,结果表明:当列车在简单链型悬挂接触网下行驶速度为250 km/h时,SBS81和DSA380应用变结构控制,接触力标准差分别降低了34.4%和18.6%,而应用最优控制则仅分别降低12.7%和10.0%;DSA250应用最优控制时接触力标准差降低了25.7%,而应用变结构控制仅降低了14.8%;SSS400+应用模糊控制时接触力标准差降低了38.1%.表明SBS81和DSA380适合变结构控制,DSA250应用最优控制表现最优,而SSS400+更适合模糊控制.

关键词：受电弓主动控制最优控制变结构控制模糊控制适用性

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长江黄石河段河道演变分析

人民长江 2011年第4期42卷 12-15页

作者：吕晓兵湖北省黄石市河道堤防管理局湖北黄石435000

为了使黄石市的城市防洪工程建设更具科学性,必须对长江黄石河段的河道演变特性,特别是近年来的变化情况有所了解。依据测绘及历史资料成果,选取4个典型断面,对黄石河段的平面形态、冲淤变化、岸线、深槽、边滩等演变情况进行了分析。... 详细信息

为了使黄石市的城市防洪工程建设更具科学性,必须对长江黄石河段的河道演变特性,特别是近年来的变化情况有所了解。依据测绘及历史资料成果,选取4个典型断面,对黄石河段的平面形态、冲淤变化、岸线、深槽、边滩等演变情况进行了分析。结果表明:由于燕矶至西塞山段边界条件较好,河势基本稳定;戴家洲分汊段有节点控制,双分汊河形将长期保持;黄石河段由于受地质和边界条件的控制,目前的微弯单一河形将维持相当长的时间;三峡工程建成后,黄石河段整体河势不会发生大的变化,但河道及岸滩将发生一定程度的冲刷,需要加强守护。

关键词：河道演变冲刷淤积洲滩变化黄石河段

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一种新的海洋浅层水合物开采法——机械-热联合法

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力学学报 2016年第5期48卷 1238-1246页

作者：张旭辉鲁晓兵中国科学院力学研究所流固耦合系统力学重点实验室北京100190

天然气水合物是国家的战略能源之一.天然气水合物分解相变使其开采难度高于常规化石能源.国际天然气水合物试验性开采表明通过降压、注热等方法难以满足商业化开采的需求,尤其在水合物位于浅层、软土情况下,持续稳定且高效率的热量供给... 详细信息

天然气水合物是国家的战略能源之一.天然气水合物分解相变使其开采难度高于常规化石能源.国际天然气水合物试验性开采表明通过降压、注热等方法难以满足商业化开采的需求,尤其在水合物位于浅层、软土情况下,持续稳定且高效率的热量供给是其瓶颈.天然气水合物机械-热联合开采是一种新概念模式,即通过粉碎水合物沉积物通过管道输运并在内部分解,这样既增加了传热的表面积,又利用海水热量和对流传热提高了能量供给效率.分析表明:利用该方法开采时水温过高会导致水合物分解过快而产生不稳定流,温度过低又导致水合物二次生成或结冰;水流流速既要能使被粉碎的水合物沉积物颗粒悬浮和流动,又不能导致流动失稳.为了实现高效安全的机械-热水合物开采,经过初步分析提出原位水合物地层粉碎的颗粒直径设定在0.1～1.0 cm之间,控制水流速度为0.22～0.67 m/s,温差保证在5 K以上,混合物中水的体积分数大于0.85.

关键词：机械-热联合开采天然气水合物对流传热海水热量

DFT Studies An Unusual Carboxylation Mechanism of the C-H Bond of Terminal Alkynes by Silver Complexes

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DFT Studies An Unusual Carboxylation Mechanism of the C-H Bo...

第十八届全国金属有机化学学术研讨会

作者：刘闯罗一张文珍 xiaobing lu 大连理工大学精细化工国家重点实验室

DFT calculations on the Ag-catalyzed carboxylation of phenyl acetylene with CO indicate that the true catalytically active species is a CsCO-coordinated Ag complex rather than neutral PhC≡CAg conventionally considered for such a *** energy barrier for the insertion of COinto the C-Ag bond of PhC≡CAg(28.8 kcal/mol)is higher than that of PhC≡CAgIand PhC≡CAgCsCOanions(19.0 and 23.6 kcal/mol,respectively).Such an anion as a key

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湖北黄石长江堤防管理信息系统建设与探讨

人民长江 2011年第5期42卷 98-101页

作者：吕晓兵湖北省黄石市河道堤防管理局湖北黄石435000

加快堤防管理信息化建设,对于提高防汛抗旱、堤防工程运行管理、抗灾应急管理等效率,充分发挥工程综合效益,具有重要的现实意义和经济价值。介绍了黄石长江堤防管理信息系统的项目建设内容、系统结构布置与功能,以及核实数据库的建设情... 详细信息

加快堤防管理信息化建设,对于提高防汛抗旱、堤防工程运行管理、抗灾应急管理等效率,充分发挥工程综合效益,具有重要的现实意义和经济价值。介绍了黄石长江堤防管理信息系统的项目建设内容、系统结构布置与功能,以及核实数据库的建设情况,论述了系统建成后的运行情况及所取得的效益。

关键词：管理信息系统工情数据库档案数据库堤防工程管理