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1Exosomes as therapeutic drug carriers and delivery vehicles across biological membranes:current perspectives and future challenges显示文摘Exosomes are small intracellular membrane-based vesicles with different compositions that are involved in several biological and pathological processes. The exploitation of exosomes as drug delivery vehicles offers important advantages compared to other nanoparticulate drug delivery systems such as liposomes and polymeric nanoparticles; exosomes are non-immunogenic in nature due to similar composition as body's own cells. In this article, the origin and structure of exosomes as well as their biological functions are outlined. We will then focus on specific applications of exosomes as drug delivery systems in pharmaceutical drug development. An overview of the advantages and challenges faced when using exosomes as a pharmaceutical drug delivery vehicles will also be discussed.Dinh Ha Ningning Yang Venkatareddy Nadithe 2016Acta Pharmaceutica Sinica B2016,6,4:104
2Comparison of scoring systems in predicting the severity of acute pancreatitis显示文摘AIM:To investigate the prognostic usefulness of several existing scoring systems in predicting the severity of acute pancreatitis(AP).METHODS:We retrospectively analyzed the prospectively collected clinical database from consecutive patients with AP in our institution between January 2011 and December 2012.Ranson,Acute Physiology and Chronic Health Evaluation(APACHE)-Ⅱ,and bedside index for severity in acute pancreatitis(BISAP)scores,and computed tomography severity index(CTSI)of all patients were calculated.Serum C-reactive protein(CRP)levels were measured at admission(CRPi)and after 24h(CRP24).Severe AP was defined as persistent organ failure for more than 48 h.The predictive accuracy of each scoring system was measured by the area under the receiver-operating curve(AUC).RESULTS:Of 161 patients,21(13%)were classified as severe AP,and 3(1.9%)died.Statistically significant cutoff values for prediction of severe AP were Ranson≥3,BISAP≥2,APACHE-Ⅱ≥8,CTSI≥3,and CRP24≥21.4.AUCs for Ranson,BISAP,APACHE-Ⅱ,CTSI,and CRP24 in predicting severe AP were 0.69(95%CI:0.62-0.76),0.74(95%CI:0.66-0.80),0.78(95%CI:0.70-0.84),0.69(95%CI:0.61-0.76),and0.68(95%CI:0.57-0.78),respectively.APACHE-Ⅱdemonstrated the highest accuracy for prediction of severe AP,however,no statistically significant pairwise differences were observed between APACHE-Ⅱand the other scoring systems,including CRP24.CONCLUSION:Various scoring systems showed similar predictive accuracy for severity of AP.Unique models are needed in order to achieve further improvement of prognostic accuracy.Joon Hyun Cho Tae Nyeun Kim Hyun Hee Chung Kook Hyun Kim 2015World Journal of Gastroenterology2015,21,8:35
3THE NONLINEAR SINGULARLY PERTURBED PROBLEMS FOR REACTION DIFFUSION EQUATIONS WITH TIME DELAY显示文摘A class of nonlinear for singularly perturbed problems for reaction diffusion equations with time delays are considered. Under suitable conditions, using theory of differential inequalities the asymptotic behavior of solution for the initial boundary value problems are studied.莫嘉琪 冯茂春 2001Acta Mathematica Scientia2001,21,2:31
4A New Discipline of Science-The Study of Open Complex Giant System and Its Methodology显示文摘This paper introduces the conception of open complex giant system and the methodology for dealing with the system, with stress on its profound significance in development of science and technology. The authors conclude that the reductionism underlying the exact science is not suitable to open complex giant system, and the only feasible alternative is the meta-synthetic engineering from the qualitative to the quantitative.Qian XuesenChina Association for Science and Technology, Beijing 100863, ChinaYu JingyuanBeijing Institute of Information and Control, P.O.Box 824, Beijing 100037, ChinaDai RuweiInstitute of Automation, Chinese Academy of Sciences, Beijing 100080, China 1993Journal of Systems Engineering and Electronics1993,4,2:28
5Progress in China's Unconventional Oil & Gas Exploration and Development and Theoretical Technologies显示文摘The new century has witnessed a strategic breakthrough in unconventional oil & gas.Hydrocarbon accumulated in micro-/nano-scale pore throat shale systems has become an important domain that could replace current oil & gas resources.Unconventional oil & gas plays an increasingly important role in our energy demand.Tight gas,CBM,heavy oil and asphaltic sand have served as a key domain of exploration & development,with tight oil becoming a 'bright spot' domain and shale gas becoming a 'hotspot' domain.China has made great breakthroughs in unconventional oil & gas resources,such as tight gas,shale gas,tight oil and CBM,and great progress in oil shale,gas hydrate,heavy oil and oil sand.China has an estimated(223-263)×10~8t of unconventional oil resources and(890-1260)×l0^(12)m^3 of gas resources.China has made a breakthrough for progress in unconventional oil & gas study.New progress achieved in fine-grained sedimentary studies related to continental open lacustrine basin large-scale shallow-water delta sand bodies,lacustrine basin central sandy clastic flow sediments and marine-continental fine-grained sediments provide a theoretical basis for the formation and distribution of basin central reservoir bodies.Great breakthroughs have been made in unconventional reservoir geology in respect of research methodology & technology,multi-scale data merging and physical simulation of formation conditions.Overall characterization of unconventional reservoirs via multi-method and multi-scale becomes increasingly popular and facilitates the rapid development of unconventional oil & gas geological theory,method and technology.The formation of innovative,continuous hydrocarbon accumulation theory,the establishment of the framework of the unconventional oil & gas geological theory system,and the determination of the implications,geological feature,formation mechanism,distribution rule and core technology of unconventional oil& gas geological study lays a theoretical foundation for extensive unconventional oil & gas exploration and development.Theories and technologies of unconventional oil & gas exploration and development developed rapidly,including some key evaluation techniques such as 'sweet spot zone' integrated evaluation and a six-property evaluation technique that uses hydrocarbon source,lithology,physical property,brittleness,hydrocarbon potential and stress anisotropy,and some key development &engineering technologies including micro-seismic monitoring,horizontal drilling & completion and 'factory-like' operation pattern, 'man-made reservoir' development,which have facilitated the innovative development of unconventional oil & gas.These breakthroughs define a new understanding in four aspects:①theoretical innovation;② key technologies;③ complete market mechanism and national policy support;and ④ well-developed ground infrastructure,which are significant for prolonging the life cycle of petroleum industry,accelerating the upgrade and development of theories and technologies and altering the global traditional energy structure.ZOU Caineng YANG Zhi ZHU Rukai ZHANG Guosheng HOU Lianhua WU Songtao TAO Shizhen YUAN Xuanjun DONG Dazhong WANG Yuman WANG Lan HUANG Jinliang WANG Shufang 2015Acta Geologica Sinica(English Edition)2015,89,3:27
6Performance of a quantum heat engine cycle working with harmonic oscillator systems显示文摘A cycle model of an irreversible heat engine working with harmonic systems is established in this paper. Based on the equation of motion of an operator in the Heisenberg picture and semi-group approach, the first law of thermodynamics for a harmonic system and the time evolution of the system are obtained. The general expressions for several important parameters, such as the work, efficiency, power output, and rate of entropy production are derived. By means of numerical analysis, the optimally operating regions and the optimal values of performance parameters of the cycle are determined under the condition of maximum power output. At last, some special cases, such as high temperature limit and frictionless case, are dis-cussed in brief.WANG JianHui HE JiZhou MAO ZhiYuan 2007Science China(Physics,Mechanics & Astronomy)2007,50,2:25
7Dynamic Modeling and Simulation of Multi-body Systems Using the Udwadia-Kalaba Theory显示文摘Laboratory experiments were conducted for falling U-chain,but explicit analytic form of the general equations of motion was not presented.Several modeling methods were developed for fish robots,however they just focused on the whole fish's locomotion which does little favor to understand the detailed swimming behavior of fish.Udwadia-Kalaba theory is used to model these two multi-body systems and obtain explicit analytic equations of motion.For falling U-chain,the mass matrix is non-singular.Second-order constraints are used to get the constraint force and equations of motion and the numerical simulation is conducted.Simulation results show that the chain tip falls faster than the freely falling body.For fish robot,two-joint Carangiform fish robot is focused on.Quasi-steady wing theory is used to approximately calculate fluid lift force acting on the caudal fin.Based on the obtained explicit analytic equations of motion(the mass matrix is singular),propulsive characteristics of each part of the fish robot are obtained.Through these two cases of U chain and fish robot,how to use Udwadia-Kalaba equation to obtain the dynamical model is shown and the modeling methodology for multi-body systems is presented.It is also shown that Udwadia-Kalaba theory is applicable to systems whether or not their mass matrices are singular.In the whole process of applying Udwadia-Kalaba equation,Lagrangian multipliers and quasi-coordinates are not used.Udwadia-Kalaba theory is creatively applied to dynamical modeling of falling U-chain and fish robot problems and explicit analytic equations of motion are obtained.ZHAO Han ZHEN Shengchao CHEN Ye-Hwa 2013Chinese Journal of Mechanical Engineering2013,26,5:22
8THEORY OF VALUES OF SINGULAR POINT IN COMPLEX AUTONOMOUS DIFFERENTIAL SYSTEMS显示文摘Consider the complex autonomous differential system (E). The main results of this paper are as follows: (i) The concept of values of singular point has been defined. It can realize the unity between the saddle values and the focal values in real systems, (ii) By defining the concept of the Lie-invariant, the constructive theorem of values of singular point and the extended symmetric principle can be obtained. (iii) All the 120 elementary Lie-invariants of (E3) have been computed. The constructive theorem being used, formulas of values of singular point and the integrability conditions of (E2) and (E(3)3) have been derived.刘一戎 李继彬 1990Science China Mathematics1990,33,1:23
9Unmanned aerial systems coordinate target allocation based on wolf behaviors显示文摘Unmanned aerial systems (UASs), especially the cluster of UAS, are highly focused and widely used in various domains. The application of small and inexpensive UAS with a large-scale group to perform complex tasks has become a mainstream trend. Thus, collaborative task assignment of UAS has become a problem that must be solved.Haibin DUAN Qing YANG Yimin DENG Pei LI Huaxin QIU Tianjie ZHANG Daifeng ZHANG Mengzhen HUO Yankai SHEN 2019Science China(Information Sciences)2019,62,1:22
10全国智能交通系统示范城市建设示例显示文摘本篇汇编了9个全国智能交通系统(Intelligent Transportation Systems,ITS)示范城市的建设示例,包括杭州、深圳、上海、北京、广州、济南、重庆、中山、青岛。分别从ITS整体建设、交通信息、交通管理、信号控制、公交智能化等方面进行介绍,从目前ITS建设运行效果来看,在改善交通运输服务质量、缓解行路难以及提高交通管理水平等方面确实发挥了积极的作用。但是,ITS实际建设过程中仍存在一些问题,如个别子系统不能整合、信息数据不能完全实现交换和共享、公交智能化建设还不够深入等等。通过介绍这些示例,希望对其他城市的ITS建设有所借鉴。陈茜 裘红妹 林群 李锋 关志超 赵一斌 张昕 蔡五三 杜勇 陈智宏 汪祖云 乐娟 谢振东 张孜 田夫 陶云 卢一夫 刘延东 周飞雄 陈观宙 2008城市交通2008,6,2:21
11MAXIMUM PRINCIPLE FOR OPTIMAL CONTROLPROBLEM OF FULLY COUPLEDFORWARD-BACKWARD STOCHASTIC SYSTEMS显示文摘The optimal control problem of fully coupled forward-backward stochastic systems is put forward. A necessary condition, called maximum principle, for an optimal control of the problem with the control domain being convex is proved.WU Zhen(College of Mathematics and System Sciences, Shandong University, Ji’nan 250100, China) 1998Systems Science and Mathematical Sciences1998,11,3:21
12Systems Biology of Plant-Microbiome Interactions显示文摘In natural environments,plants are exposed to diverse microbiota that they interact with in complex ways.While plant-pathogen interactions have been intensely studied to understand defense mechanisms in plants,many microbes and microbial communities can have substantial beneficial effects on their plant host.Such beneficial effects include improved acquisition of nutrients,accelerated growth,resilience against pathogens,and improved resistance against abiotic stress conditions such as heat,drought,and salinity.However,the beneficial effects of bacterial strains or consortia on their host are often cultivar and species specific,posing an obstacle to their general application.Remarkably,many of the signals that trigger plant immune responses are molecularly highly similar and often identical in pathogenic and beneficial microbes.Thus,it is unclear what determines the outcome of a particular microbe-host interaction and which factors enable plants to distinguish beneficials from pathogens.To unravel the complex network of genetic,microbial,and metabolic interactions,including the signaling events mediating microbe-host interactions,comprehensive quantitative systems biology approaches will be needed.Patricia A.Rodriguez Michael Rothballer Soumitra Paul Chowdhury Thomas Nussbaumer Caroline Gutjahr Pascal Falter-Braun 2019Molecular Plant2019,12,6:20
13国内医院信息平台现状及解决方案分析显示文摘介绍了国内医院信息平台建设的现状以及'集成难'的问题,阐述了医院信息平台的建设内容与建设模式,从核心架构与技术特点等方面详细分析了国外Orion、InterSystems等知名公司提供的解决方案。指出了构建医院信息平台时要从最紧迫的需求入手,逐步推进,并协调不同厂商间的利益,这样才能更好地为医院内部信息共享提供一个数据共享与交换平台,对外提供一个统一的信息出口,助力智慧医院建设战略目标的实现。李伟 张麟 王爱娥 卢敬泰 周丁华 王士泉 2018医疗卫生装备2018,39,2:19
14Shift to a low carbon society through energy systems design显示文摘Concern about global warming calls for an advanced approach for designing an energy system to reduce carbon emissions as well as to secure energy security for each country.Conventional energy systems tend to introduce different technologies with high conversion efficiency,leading to a higher average efficiency.Advanced energy systems can be achieved not by an aggregate form of conversion technologies but by an innovative system design itself.The concept of LCS(low carbon society) is a unique approach having multi-dimensional considerations such as social,economic and environmental dimensions.The LCS aims at an extensive restructuring of worldwide energy supply/demand network system by not only replacing the conventional parts with the new ones,but also integrating all the necessary components and designing absolutely different energy networks.As a core tool for the LCS design,energy-economic models are applied to show feasible solutions in future with alternatives such as renewable resources,combined heat and power,and smart grid operations.Models can introduce changes in energy markets,technology learning in capacity,and penetration of innovative technologies,leading to an optimum system configuration under priority settings.The paper describes recent trials of energy models application related to waste-to-energy,clean coal,transportation and rural development.Although the modelling approach is still under investigation,the output clearly shows possible options having variety of technologies and linkages between supply and demand sides.Design of the LCS means an energy systems design with the modelling approach,which gives solution for complex systems,choices among technologies,technology feasibility,R&D targets,and what we need to start.Toshihiko NAKATA Mikhail RODIONOV Diego SILVA Joni JUPESTA 2010Science China(Technological Sciences)2010,53,1:19
15A review of aerial manipulation of small-scale rotorcraft unmanned robotic systems显示文摘Small-scale rotorcraft unmanned robotic systems(SRURSs) are a kind of unmanned rotorcraft with manipulating devices. This review aims to provide an overview on aerial manipulation of SRURSs nowadays and promote relative research in the future. In the past decade, aerial manipulation of SRURSs has attracted the interest of researchers globally. This paper provides a literature review of the last 10 years(2008–2017) on SRURSs, and details achievements and challenges. Firstly, the definition, current state, development, classification, and challenges of SRURSs are introduced. Then, related papers are organized into two topical categories: mechanical structure design, and modeling and control. Following this, research groups involved in SRURS research and their major achievements are summarized and classified in the form of tables. The research groups are introduced in detail from seven parts. Finally, trends and challenges are compiled and presented to serve as a resource for researchers interested in aerial manipulation of SRURSs. The problem,trends, and challenges are described from three aspects. Conclusions of the paper are presented,and the future of SRURSs is discussed to enable further research interests.Xilun DING Pin GUO Kun XU Yushu YU 2019Chinese Journal of Aeronautics2019,32,1:18
16Depositional architecture and developing settings of large-scale incised valley and sub-marine gravity flow systems in the Yinggehai and Qiong-dongnan basins,South China Sea显示文摘In the Ying-Qiong basins in the South China Sea developed a set of giant inner shelf slope and submarine gravity flow deposits in the Ying-Huang formations since the Late Miocene. These deposits can be classified into 9 sequences in which slope slump-debris flow, slope fan and particularly, the large-scale axial basin-floor incised valley fills have been recognized. They were distributed in a distinctive pattern attributed to tectonic control. The development ofshelf slopes and abyssal plains in the basins was related to the last episode of rapid subsidence and a large amount of sediment inputs. Large-scale basin-floor incised valleys, formed during the late Miocene and Pliocene, indicate several major sea level falls that occurred in the South China Sea.LIN Changsong LIU Jingyan CAI Shixiang ZHANG Yanmei LU Ming LI Jie 2001Chinese Science Bulletin2001,46,8:18
17A general end-to-end diagnosis framework for manufacturing systems显示文摘The manufacturing sector is envisioned to be heavily influenced by artificial-intelligence-based technologies with the extraordinary increases in computational power and data volumes. A central challenge in the manufacturing sector lies in the requirement of a general framework to ensure satisfied diagnosis and monitoring performances in different manufacturing applications. Here, we propose a general data-driven,end-to-end framework for the monitoring of manufacturing systems. This framework, derived from deep-learning techniques, evaluates fused sensory measurements to detect and even predict faults and wearing conditions. This work exploits the predictive power of deep learning to automatically extract hidden degradation features from noisy, time-course data. We have experimented the proposed framework on 10 representative data sets drawn from a wide variety of manufacturing applications. Results reveal that the framework performs well in examined benchmark applications and can be applied in diverse contexts,indicating its potential use as a critical cornerstone in smart manufacturing.Ye Yuan Guijun Ma Cheng Cheng Beitong Zhou Huan Zhao Hai-Tao Zhang Han Ding 2020National Science Review2020,7,2:18
18EXISTENCE OF ALMOST PERIODIC SOLUTIONS FOR DIFFERENCE SYSTEMS显示文摘In this work, we first define the notions of almost periodic sequences, asymptotically almost periodic sequences, as well as uniformly almost periodic sequences,and reveal their basic properties. Then for the almost periodic difference systems of general form we establish the criteria of existence for almost periodic solutions.Especially, several existence theorems are proved in terms of discrete Liapunov functions.张书年 2000Annals of Differential Equations2000,16,2:17
19Reliability Design for Impact Vibration of Hydraulic Pressure Pipeline Systems显示文摘The research of reliability design for impact vibration of hydraulic pressure pipeline systems is still in the primary stage,and the research of quantitative reliability of hydraulic components and system is still incomplete.On the condition of having obtained the numerical characteristics of basic random parameters,several techniques and methods including the probability statistical theory,hydraulic technique and stochastic perturbation method are employed to carry out the reliability design for impact vibration of the hydraulic pressure system.Considering the instantaneous pressure pulse of hydraulic impact in pipeline,the reliability analysis model of hydraulic pipeline system is established,and the reliability-based optimization design method is presented.The proposed method can reflect the inherent reliability of hydraulic pipe system exactly,and the desired result is obtained.The reliability design of hydraulic pipeline system is achieved by computer programs and the reliability design information of hydraulic pipeline system is obtained.This research proposes a reliability design method,which can solve the problem of the reliability-based optimization design for the hydraulic pressure system with impact vibration practically and effectively,and enhance the quantitative research on the reliability design of hydraulic pipeline system.The proposed method has generality for the reliability optimization design of hydraulic pipeline system.ZHANG Tianxiao LIU Xinhui 2013Chinese Journal of Mechanical Engineering2013,26,5:17
20Adaptive Iterative Learning Control for Nonlinearly Parameterized Systems with Unknown Time-varying Delay and Unknown Control Direction显示文摘This paper proposes a new adaptive iterative learning control approach for a class of nonlinearly parameterized systems with unknown time-varying delay and unknown control direction.By employing the parameter separation technique and signal replacement mechanism,the approach can overcome unknown time-varying parameters and unknown time-varying delay of the nonlinear systems.By incorporating a Nussbaum-type function,the proposed approach can deal with the unknown control direction of the nonlinear systems.Based on a Lyapunov-Krasovskii-like composite energy function,the convergence of tracking error sequence is achieved in the iteration domain.Finally,two simulation examples are provided to illustrate the feasibility of the proposed control method.Dan Li Jun-Min Li Department of Mathematics,Xidian University,Xi an 710071,China 2012International Journal of Automation and computing2012,9,6:17
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