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光度立体技术的物体三维表面重建算法模拟与评价

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计算机工程与设计 2010年第16期31卷 3635-3639页

作者：吕东辉张栋孙九爱上海大学通信与信息工程学院上海200072 University of the West of England Bristol BS16 1QY UK

为了提高基于光度立体法的物体三维表面重建精度,研究了几种常用三维表面重建算法的适用范围。介绍了几种常用重建算法(变分法、金字塔法、代数法)的基本原理及求解方法,指出了表面方向梯度的求解准确度是三维表面重建过程中的难点。在... 详细信息

为了提高基于光度立体法的物体三维表面重建精度,研究了几种常用三维表面重建算法的适用范围。介绍了几种常用重建算法(变分法、金字塔法、代数法)的基本原理及求解方法,指出了表面方向梯度的求解准确度是三维表面重建过程中的难点。在此基础上建立了朗伯半球体模型和实际拍摄的玻璃灯罩,从重建速度、重建精度等方面对几种算法进行了比较和评价。最后通过实验模拟和算法性能评价,表明了常用算法的重建精确度有限,并且对三维重建今后的研究进行了展望。

关键词：光度立体技术变分法金字塔法代数法重建精度表面方向梯度

In vivo real-time monitoring delayed administration of M2 macrophages to enhance healing of tendon by NIR-II fluorescence imaging

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Nano Research 2024年第5期17卷 4379-4390页

作者： Yuzhou Chen Mo Chen Chengxuan Yu Huizhu Li Liman Sai Nguyen T.K.Thanh Yueming Wang Yan Wo Jian Zhang Xing Yang Evgenii L.Guryev Andrei V.Zvyagin Hao De Min Tang Shiyi Chen Yunxia Li Yuefeng Hao Sijia Feng Jun Chen Sports Medicine Institute of Fudan University Department of Sports MedicineHuashan HospitalFudan UniversityShanghai 200040China Department of Orthopedic Surgery Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Department of Bone and Joint Surgery Department of OrthopedicsRenji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200001China Department of Physics Shanghai Normal UniversityShanghai 200234China Biophysics Group Department of Physics and AstronomyUniversity College LondonLondon WC1E 6BTUK UCL Healthcare Biomagnetic and Nanomaterials Laboratories London W1S 4BSUK Department of Anatomy and Physiology School of MedicineShanghai Jiao Tong UniversityShanghai 200025China Department of Orthopedics Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhou 215500China Institute of Biology and Biomedicine Lobachevsky State University of Nizhny NovgorodNizhny Novgorod 603950Russia Mathematical Institute University of OxfordOxford OX26GGUK Institute of Natural Sciences School of MathematicsShanghai Jiao Tong UniversityShanghai 200240China

The administration time is a critical but long-neglected point in cell therapy based on macrophages because the incorrect time of macrophage administration could result in diverse outcomes regarding the same macrophage *** this work,the second near-infrared(NIR-II)fluorescence imaging in vivo tracking of M2 macrophages during a pro-healing therapy in the mice model of rotator cuff injury revealed that the behavior of administrated macrophages was influenced by the timing of their *** delayed cell therapy(DCT)group had a longer retention time of injected M2 macrophages in the repairing tissue than that in the immediate cell therapy(ICT)*** Keller-Segel model and histological analysis further demonstrated that DCT altered the chemotaxis of M2 macrophages and improved the healing outcome of the repaired structure in comparison with *** results offer a possible explanation of previous conflicting results on reparative cell therapy and provoke reconsideration of the timing of these therapies.

关键词： macrophage cell therapy NIR-II in vivo imaging delayed therapy tendon healing

A primitive confuciusornithid bird from China and its implications for early avian flight

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Science China Earth Sciences 2008年第5期51卷 625-639页

作者： Michael J. BENTON Department of Earth Sciences University of Bristol Bristol BS8 1RJ UK

Confuciusornithids, lived from 120―125 million years ago, form a basal bird group and include the oldest birds with horny beaks. Here we describe Eoconfuciusornis zhengi, gen. et sp. nov. from the Early Cretaceous Dabeigou Formation (131 Ma) in Fengning, Hebei Province, northern China. It repre- sents a new and, more primitive than other known, member of this group and extends the lifespan of this family to 11 Ma, the longest of any known Early Cretaceous avian lineages. Furthermore, Eoconfuciusornis and its relatives present many osteological transformations, such as the size increase of the deltopectoral crest of the humerus and the keel of the sternum, apparently an adaptation toward improved flight in the evolution of the Confuciusornithidae.

关键词： Birds Early Cretaceous confuciusornithids flight

Game and Dynamic Communication Path-Based Pricing Strategies for Microgrids Under Communication Interruption

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IEEE/CAA Journal of Automatica Sinica 2023年第4期10卷 1032-1047页

作者： Bo Zhang Chunxia Dou Dong Yue Ju H.Park Yudi Zhang Zhanqiang Zhang Institute of Advanced Technology Nanjing University of Posts and TelecommunicationsNanjing 210023China Department of Electrical Engineering Yeungnam UniversityGyeongsan 38541South Korea Nanjing University Nanjing 210093China.She is now with the University of BristolBristol BS81QUUK

Nowadays,the microgrid cluster is an important application scenario for energy *** trading,one of the most important research directions is the issue of *** determine reasonable pricing for the microgrid cluster,data communication is used to create the cyber-physical system(CPS),which can improve the observability of ***,the following works are carried out in the *** the physical layer:1)Regarding trading between microgrids and the load,based on the generalized game theory,an optimal pricing strategy is proposed,which takes into account the interactive relationships among microgrids and transforms the pricing problem into a Nikaido-Isoda function to obtain the optimal prices conveniently;2)Regarding peer-to-peer trading between two microgrids,based on evolutionary game theory and the penalty mechanism,the optimal sale price of the seller is selected with boundary *** the cyber layer,regarding the communication interruption issue existing in pricing(i.e.,the game process),based on the principle of matching the performance of the path with the importance degree of the data,a dynamic regulating method of paths is proposed,i.e.,adopting a new path to re-transmit the interrupted data to the ***,the effect of the proposed strategies is verified by case studies.

关键词： Communication interruption dynamic regulating

Manufacturing Titanium Metal Matrix Composites by Consolidating Matrix Coated Fibres

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Journal of Materials Science & Technology 2005年第5期21卷 647-651页

作者： Hua-Xin PENGDepartment of Aerospace Engineering, University of bristol, University Walk, bristol, bs8 1TR, UK Department of Aerospace Engineering University of Bristol University Walk Bristol BS8 1TR United Kingdom

Titanium metal matrix composites （TiMMCs） reinforced by continuous silicon carbide fibres are being developed for aerospace applications. TiMMCs manufactured by the consolidation of matrix-coated fibre （MCF） method offer optimum properties because of the resulting uniform fibre distribution, minimum fibre damage and fibre volume fraction control. In this paper, the consolidation of Ti-6Al-4V matrix-coated SiC fibres during vacuum hot pressing has been investigated. Experiments were carried out on multi-ply MCFs under vacuum hot pressing （VHP）. In contrast to most of existing studies, the fibre, arrangement has been carefully controlled either in square or hexagonal arrays throughout the consolidated sample. This has enabled the dynamic consolidation behaviour of MCFs to be demonstrated by eliminating the fibre re-arrangement during the VHP process. The microstructural evolution of the matrix coating was reported and the deformation mechanisms involved were discussed.

关键词： Titanium matrix composites Matrix-coated fibres Vacuum hot pressing Microstructure Dynamic denslfication

SAHRC：一种基于分簇的无线传感器网络路由控制算法

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电子与信息学报 2011年第8期33卷 2013-2017页

作者：张小波程良伦 Zhu Quan-min 广东工业大学自动化学院广州510006 英国西英格兰大学计算机工程与数学学院布里斯托尔BS16 1QY

设计特定应用场合的路由控制算法是无线传感器网络路由控制领域研究的热点之一。在深入研究经典网络路由算法(LEACH)的基础上,提出一种基于分簇的自适应混合型路由控制(SAHRC)算法。该算法针对大规模事件驱动型网络场景应用,采用网内节... 详细信息

设计特定应用场合的路由控制算法是无线传感器网络路由控制领域研究的热点之一。在深入研究经典网络路由算法(LEACH)的基础上,提出一种基于分簇的自适应混合型路由控制(SAHRC)算法。该算法针对大规模事件驱动型网络场景应用,采用网内节点启发机制解决了LEACH算法面对大规模网络缺乏自适应性,未考虑节点剩余能量,通信效率难以得到保障等问题。仿真结果表明,新的SAHRC算法比原有LEACH算法有更好的节能性和稳定性。

关键词：无线传感器网络路由控制算法自适应分簇自适应混合型路由控制(SAHRC)

SARS-CoV-2 spike variants differ in their allosteric responses to linoleic acid

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Journal of Molecular Cell Biology 2023年第3期15卷 55-66页

作者： A.Sofia F.Oliveira Deborah K.Shoemark Andrew D.Davidson Imre Berger Christiane Schaffitzel Adrian J.Mulholland School of Chemistry Centre for Computational ChemistryUniversity of BristolBristol BS81TSUK School of Chemistry University of BristolBristol BS81TSUK School of Biochemistry University of BristolBristol BS81TDUK School of Cellular and Molecular Medicine University of BristolUniversity WalkBristol BS81TDUK School of Chemistry Max Planck Bristol Centre for Minimal BiologyBristol BS81TSUK

The SARS-CoV-2 spike protein contains a functionally important fatty acid(FA)binding site,which is also found in some other coronaviruses,***-CoV and *** occupancy of the FA site by linoleic acid(LA)reduces infectivity by‘locking’the spike in a less infectious ***,we use dynamical-nonequilibrium molecular dynamics(D-NEMD)simulations to compare the allosteric responses of spike variants to LA removal.D-NEMD simulations show that the FA site is coupled to other functional regions of the protein,*** receptor-binding motif(RBM),N-terminal domain(NTD),furin cleavage site,and regions surrounding the fusion peptide.D-NEMD simulations also identify the allosteric networks connecting the FA site to these functional *** comparison between the wild-type spike and four variants(Alpha,Delta,Delta plus,and Omicron BA.1)shows that the variants differ significantly in their responses to LA *** allosteric connections to the FA site on Alpha are generally similar to those on the wild-type protein,with the exception of the RBM and the S71–R78 region,which show a weaker link to the FA *** contrast,Omicron is the most different variant,exhibiting significant differences in the RBM,NTD,V622–L629,and furin cleavage *** differences in the allosteric modulation may be of functional relevance,potentially affecting transmissibility and *** comparison of the effects of LA on SARS-CoV-2 variants,including emerging variants,is warranted.

关键词： SARS-CoV-2 spike allosteric modulation D-NEMD simulations fatty acid binding site SARS-CoV-2 variants

质膜NAD(P)H氧化酶参予金瓜炭疽(Colletotrichum lagerarium)细胞壁激发子诱导人参细胞产生激发反应(英文)

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Acta Botanica Sinica 2003年第1期45卷 32-39页

作者：胡向阳 Steven J.NEILL 方建颖蔡伟明汤章城中国科学院上海生命科学研究院植物生理生态研究所上海200032 Centre for Research in Plant Science University of the West of England BristolColdharbour LaneBrisiol BS16 1QYUnited Kingdom

在人参(Panax ginseng ***)悬浮细胞质膜上测出了NAD(P)H氧化酶活性。这类NAD(P)H氧化酶活性可以被金瓜炭疽细胞壁激发子(Cle)诱导。Cle处理还能诱导人参悬浮细胞的氧进发、促进人参悬浮细胞的皂苷合成、提高苯丙氨酸解氨酶(PAL)的活力... 详细信息

在人参(Panax ginseng ***)悬浮细胞质膜上测出了NAD(P)H氧化酶活性。这类NAD(P)H氧化酶活性可以被金瓜炭疽细胞壁激发子(Cle)诱导。Cle处理还能诱导人参悬浮细胞的氧进发、促进人参悬浮细胞的皂苷合成、提高苯丙氨酸解氨酶(PAL)的活力、以及诱导查尔式酮酶(CHS)的累积和细胞壁上抗性相关蛋白基因脯氨酸富裕蛋白基因hrgp(Hydroxyprolin-rich glycoproleins)的表达。当用哺乳动物白细胞质膜NADPH氧化酶的特异性抑制剂二亚苯基碘(Diphenylene iodonium,DPI)与奎吖因(quinacrine)预处理人参悬浮细胞30 min 后,Cle诱导的H2O2释放与Cle激活的质膜NAD(P)H氧化酶活性被抑制,同时Cle诱导的PAL活性及CHS的积累下降,皂苷合成与hrgp的表达被抑制。由此推测:人参细胞质膜NAD(P)H氧化酶与哺乳动物白细胞质膜NADPH氧化酶有很大的相似性。在Cle激发人参悬浮细胞产生氧进发的过程中,NAD(P)H氧化酶活性被诱导从而导致H2O2的产生,H2O2作为第二信使,激活苯丙氨酸途径,诱发人参皂苷的合成及hrgp防御基因的表达。这一过程中还涉及到Ca2+内流,胞内Ca2+浓度的升高,蛋白磷酸化与去磷酸化。人参细胞质膜NAD(P)H氧化酶在人参细胞对Cle的反应过程中起一种介导作用。因此可能存在由Cle刺激,NAD(P)H氧化酶被诱导,H2O2释放,到人?

关键词：质膜NAD(P)H氧化酶金瓜炭疽人参皂苷细胞壁激发子诱导人参细胞激发反应信号转导

Video quality based link adaptation for low latency video transmission over WLANs

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 847-856页

作者： FERR Pierre DOUFEXI Angela CHUNG-HOW James NIX Andrew BULL David University of bristol Department of Electrical and Electronic Engineering Centre for Communications Research Bristol BS8 1UB UK ProVision Communication Technologies Bristol BS4 4EU UK

Wireless Local Area Networks (WLANs) such as IEEE 802.11a/g and Hiperlan/2 utilise numerous transmission modes, each providing different throughputs and reliability levels. Many link adaptation algorithms proposed in the literature either maximise the error-free data throughput based on channel conditions or are based on the number of failed transmissions. However, these algo- rithms do not take into account the content of the data stream and strongly rely on the use of Automatic Repeat Requests (ARQs). Low latency video applications such as real-time video transmission may require no retransmission, or only a limited number of retrans- missions. Moreover, completely error-free communication is not essential, especially if robust video compression techniques are applied. In such scenarios, improved decoded video quality can be obtained with a video stream transmitted at a higher bit rate using a higher link speed but with some degree of transmission error, rather than an error-free video stream at a lower bit rate using a lower link speed. In this work, we investigate a link adaptation scheme that improves the Quality of Service (QoS) for video transmission, based on the overall received video quality (Peak Signal to Noise Ratio, PSNR), rather than by maximising the error-free throughput. We also study a practical link adaptation approach that uses PER thresholds at the PHY layer. An empirical study showed that thresholds for switching from one mode to another are much lower (almost error free) than those currently used by throughput based schemes. We show that traditional link adaptation strategies are not appropriate for real-time video transmission with no retransmis- sion. Simulation results using the H.264 video compression standard over IEEE 802.11a are presented.

关键词： Link adaptation Wireless LAN Video quality Peak Signal to Noise Ratio (PSNR) Packet Error Rate (PER)