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Recent advances in cell imaging and cytotoxicity of intracellular stimuli-responsive nanomaterials

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Science Bulletin 2015年第23期60卷 1973-1979页

作者： wenbo zhang Changyou Gao Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University

The stimuli-responsive nanomaterials are gaining more and more interest in the biological field,including cell imaging and biosensing etc. Nanomaterials in response to the bio-relevant stimuli(i.e., p H, enzymes and other bioactive molecules) can be utilized to enhance imaging(i.e., optical imaging, MRI, and multi-mode imaging) sensitivity via disease site-specific delivery and controlled release, which helps to diagnose cancer at an early stage or to monitor progression during treatment. In the triggered responsive process, smart nanomaterials undergo changes in physiochemical properties that can cause cytotoxicity or influence on cell functions due to the interactions between nanomaterials and cells. In order to promote the design and fabrication of effective platforms for therapeutics and diagnostics, special attention should be paid to these effects. By taking the advantages of intracellular stimuli, the controlled self-assembly in living cells can be achieved, which has been used for various in situ detections and insights into biological self-assembly. In this review, the recent advances in cell imaging, cytotoxicity and self-assembly of intracellular stimuli-responsive nanomaterials are summarized. Some principles for the further design and applications of intracellular stimuli-responsive nanomaterials and future perspectives are discussed.

关键词： Stimuli-responsive · Nanomaterials ·Cell imaging · Cytotoxicity · Self-assembly

A benefit-aware on-demand provisioning approach for multi-tier applications in cloud computing

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Frontiers of Computer Science 2013年第4期7卷 459-474页

作者： Heng WU wenbo zhang Jianhua zhang Jun WEI Tao HUANG Institute of Software Chinese Academy of Sciences Beijing 100190 China State Key Laboratory Computer Science Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Dynamic resource provisioning is a challenging technique to meet the service level agreement （SLA） requirements of multi-tier applications in virtualization-based cloud computing. Prior efforts have addressed this challenge based on either a cost-oblivious approach or a cost-aware approach. However, both approaches may suffer frequent SLA violations under flash crowd conditions. Because they ignore the benefit gained that a multi-tier application continuously guarantees the SLA in the new configuration. In this paper, we propose a benefit-aware approach with feedback control theory to solve this problem. Experimental results based on live workload traces show that our approach can reduce resource provisioning cost by as much as 30% compared with a costoblivious approach, and can effectively reduce SLA viola- tions compared with a cost-aware approach.

关键词： cloud computing visualization resource recon-figuration feedback control benefit-aware

Strong motion characteristics of the M_w 6.6 Lushan earthquake,Sichuan,China——an insight into the spatial difference of a typical thrust fault earthquake

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 203-216页

作者： Hu Jinjun zhang wenbo Xie Lili zhang Qi Jiang Zhijun Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering Mechanics China Earthquake Administration College of Earth Science University of Chinese Academy of Science School of Civil Engineering Harbin Institute of Technology

Near-field strong ground motions are useful for engineering seismology studies and seismic design, but dense observation networks of damaging earthquakes are still rare. In this study, based on the strong-motion data from the M w 6.6 Lushan earthquake, the ground motion parameters in different spatial regions are systematically analyzed, and the contributions from different effects, like the hanging-wall effect, directivity effect, and attenuation effect are separated to the extent possible. Different engineering parameters from the observed ground motions are compared with the local design response spectra and a new attenuation relation of Western China. General results indicate that the high frequency ground motion, like the peak ground acceleration, on two sides of the fault plane is sensitive to the hanging-wall effect, whereas the low frequency ground motion, like the long period spectral acceleration, in the rupture propagation direction is affected by the directivity effect. Moreover, although the M w 6.6 Lushan earthquake is not a large magnitude event, the spatial difference of ground motion is still obvious; thus, for a thrust faulting earthquake, in addition to the hanging effect, the directivity effect should also be considered.

关键词： Lushan earthquake near-fi eld ground motion direct

Short-term exposure to fine particulate matter and hospital admission for stroke:a meta-analysis

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中国循环杂志 2018年第S1期33卷 118-119页

作者： wenbo zhang State Key Laboratory of Cardiovascular Disease National Center for Cardiovascular DiseasesFuwai HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Objective Air pollution is an important risk factor for cardiovascular diseases throughout the *** particulate matter(PM)air pollution alone is responsible for over three million deaths each *** and growing literature has explored whether short-term exposure to fine particulate matter is associated with stroke,but results from prior studies have been *** fill this gap,we assessed the evidence quantitatively from epidemiological time-series studies published worldwide and determined whether short-term exposure to fine particulate matter(<2.5μm or<10μm)diameter[PM2.5 and PM10]was associated with increased risk of hospital admission for stroke(including ischemic and hemorrhagic stroke).

关键词： Air pollution cardiovascular diseases particulate matter(PM)

Bio-Based Waterborne Poly(Vanillin-Butyl Acrylate)/MXene Coatings for Leather with Desired Warmth Retention and Antibacterial Properties

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Engineering 2024年第5期36卷 250-263页

作者： Jianzhong Ma Li Ma Lei zhang wenbo zhang Qianqian Fan Buxing Han College of Bioresources Chemical and Materials Engineering Shaanxi University of Science and TechnologyXi’an 710021China Xi’an Key Laboratory of Green Chemicals and Functional Materials Xi’an 710021China College of Chemistry and Chemical Engineering Shaanxi University of Science and TechnologyXi’an 710021China Shaanxi Collaborative Innovation Center of Industrial Auxiliary Chemistry and Technology Shaanxi University of Science and TechnologyXi’an 710021China Institute of Chemistry Chinese Academy of SciencesBeijing 100190China

This study presents a solvent-free,facile synthesis of a bio-based green antibacterial agent and aromatic monomer methacrylated vanillin(MV)using *** resulting MV not only imparted antibacterial properties to coatings layered on leather,but could also be employed as a green alternative to petroleum-based carcinogen styrene(St).Herein,MV was copolymerized with butyl acrylate(BA)to obtain waterborne bio-based P(MV-BA)miniemulsion via miniemulsion ***,MXene nanosheets with excellent photothermal conversion performance and antibacterial properties,were introduced into the P(MV-BA)miniemulsion by ultrasonic *** the gradual solidification of P(MV-BA)/MXene nanocomposite miniemulsion on the leather surface,MXene gradually migrated to the surface of leather coatings due to the cavitation effect of ultrasonication and amphiphilicity of MXene,which prompted its full exposure to light and bacteria,exerting the maximum photothermal conversion efficiency and significant antibacterial *** particular,when the dosage of MXene nanosheets was 1.4 wt%,the surface temperature of P(MV-BA)/MXene nanocomposite miniemulsioncoated leather(PML)increased by about 15℃ in an outdoor environment during winter,and the antibacterial rate against Escherichia coli and Staphylococcus aureus was nearly 100%under the simulated sunlight treatment for 30 ***,the introduction of MXene nanosheets increased the air permeability,water vapor permeability,and thermal stability of these *** study provides a new insight into the preparation of novel,green,and waterborne bio-based nanocomposite coatings for leather,with desired warmth retention and antibacterial *** can not only realize zerocarbon heating based on sunlight in winter,reducing the use of fossil fuels and greenhouse gas emissions,but also improve ability to fight off invasion by harmful bacteria,viruses,and other microorganisms.

关键词： MXene nanosheets Vanillin Styrene substitute Leather coating Photothermal conversion Warmth retention Antibacterial properties

Time Domain Synchronous OFDM System for Optical Fiber Communications

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China Communications 2019年第9期16卷 155-164页

作者： Chenxin Jing Xianfeng Tang Xiaoguang zhang Lixia Xi wenbo zhang State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

A spectrum efficient OFDM scheme named Time Domain Synchronous-OFDM(TDS-OFDM)is introduced into coherent optical transmission system,in which the pseudo noise(PN)sequence is exploited as guard interval to realize frame synchronization,compensate the carrier frequency offset(CFO),and estimate and equalize channel *** there is no pilot signals or training symbols in TDS-OFDM,the proposed scheme can achieve higher spectral efficiency(SE)above 10%improvement comparing with *** proposed method is implemented and verified in a 28GBaud QPSK OFDM system and a 28GBaud 16QAM OFDM *** is demonstrated that the proposed scheme shows high CFO estimation accuracy and synchronous *** CFO and linewidth of laser source set as 100MHz and 100kHz respectively,BER of QPSK OFDM system is below 3.8e-3 at the optical signal-to-noise ratio(OSNR)of 13dB,and BER of 16QAM OFDM system is below 3.8e-3 at the OSNR of 20dB.

关键词： channel estimation carrier frequencyoffset (CFO) compensation pseudonoise (PN) sequence synchronization timedomain synchronous OFDM (TDS-OFDM)

Boundary integral equations for dynamic rupture propagation on vertical complex fault system in half-space:Theory

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Earthquake Science 2010年第2期23卷 177-190页

作者： Haiming zhang Xiaoping Rui wenbo zhang Department of Geophysics School of Earth and Space Sciences Peking University Beijing 100871 China College of Resources and Environment Graduate University of Chinese Academy of Sciences Beijing 100049 China College of Earth Sciences Graduate University of Chinese Academy of Sciences Beijing 100049 China

The boundary integral equation method （BIEM） is now widely used in numerical studies on earthquake rupture dynamics, and is proved to be a powerful tool to deal with problems on complex fault system. However, since this method heavily lies on the specific forms of Green＇s function and only the Green＇s function in full-space has a closed analytic expression, it is usually limited to a full-space medium. In this study, as a first step to extend this method to an arbitrary complex fault system in half-space, the boundary integral equations （BIEs） for dynamic strike-slip on vertical complex fault system in half-space are derived based on exact Green＇s function for isotropic and homogeneous half-space. Effect of the geometry of the complex fault system are dealt with carefully. Final BIEs is composed of two parts： contribution from full-space, which has been thoroughly investigated by Aochi and his co-workers by using the Green＇s function for full-space, and that from free surface, which is studied in detail in this study.

关键词： seismic source dynamics boundary integral equation complex fault system free surface

The Motion Planets Detection and Tracking Algorithm Based on Gestalt Principle

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Chinese Journal of Electronics 2018年第4期27卷 808-812页

作者： QIU Shi TANG Ying zhang wenbo FENG Jun zhang Fuchun LI Chen Xi'an Institute of Optics and Precision Mechanics of CAS Chengdu University of Technology College of Information Science & Technology School of Electronic Engineering Xidian University School of Information Science and Technology Engineering Northwestern University Department of Aviation Theory Aviation University of Air Force Institute of Deep-sea Science and Engineering Chinese Academy of Sciences

The moving planets have a few of pixels which can lead to lacking enough image characteristics when tracking them. So we propose the motion planets detection and tracking algorithm based on gestalt principle. We structure Gaussian mixture model to detect the motion area from the visual cognition perspective, and use astronomy images graphics characteristics to confirm the planet position. Then we propose space-time fusion model for tracking planet. All the experiments use 1000 16-bitframe images of wide view CCD camera which contain 5684 motion planets in total. The results show that our algorithm reaches an accuracy of 94% and has robustness.

关键词： The moving planets Gestalt principle Tracking

A Blockchain and CP-ABE Based Access Control Scheme with Fine-Grained Revocation of Attributes in Cloud Health

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Computers, Materials & Continua 2024年第2期78卷 2787-2811页

作者： Ye Lu Tao Feng Chunyan Liu wenbo zhang School of Computer&Communication Lanzhou University of TechnologyLanzhou730000China School of Economics&Management Lanzhou University of TechnologyLanzhou730000China School of Computer Science Baoji University of Arts and ScienceBaoji721000China

The Access control scheme is an effective method to protect user data *** access control scheme based on blockchain and ciphertext policy attribute encryption(CP–ABE)can solve the problems of single—point of failure and lack of trust in the centralized ***,it also brings new problems to the health information in the cloud storage environment,such as attribute leakage,low consensus efficiency,complex permission updates,and so *** paper proposes an access control scheme with fine-grained attribute revocation,keyword search,and traceability of the attribute private key distribution *** technology tracks the authorization of attribute private *** credit scoring method improves the Raft protocol in consensus ***,the interplanetary file system(IPFS)addresses the capacity deficit of *** the premise of hiding policy,the research proposes a fine-grained access control method based on users,user attributes,and file *** optimizes the data-sharing *** the same time,Proxy Re-Encryption(PRE)technology is used to update the access *** proposed scheme proved to be *** analysis and experimental results show that the proposed scheme has higher efficiency and more *** can meet the needs of medical institutions.

关键词： Blockchain access-control CP-ABE cloud health