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Biological Properties of Chitosan Films with Different Degree of Deacetylation

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Journal of Materials Science & Technology 2008年第5期24卷 700-708页

作者： Jing ChanG Wanshun liu Baoqin han Bing liu Department of Marine Life Science Ocean University of China Qingdao 266003 China

Chitin and chitosan films were prepared by solution casting method. Chitosan specimens used in this study were deacetylated by 50.4%, 69.2%, 85.5% and 96.3%. Their water content, protein adhesion ability, cytocompatibility, cell adhesion ability, in vitro and vivo degradability and biocompatibility were evaluated. Results indicated that with the degree of deacetylation （DD） between 50% and 70%, the chitosan showed higher water content. The higher the DD, the stronger protein adhesion ability the chitosan had. All the films have good cytocompatibility and the films with higher DD have better cell adhesion ability. Chitin films degraded more rapidly than others, which disappeared in 2 to 4 weeks after they were implanted in subcutaneous tissue and musculature. Their inflammatory reaction became weaker as the films degraded. As the DD got higher, the films degraded slower. The films of DD 85.5% and DD 90.3% even didn＇t disappeared in 12 weeks after they were implanted. Their inflammatory reaction was mild at the beginning of degradation, and became severe in 4 to 8 weeks, then weaken at last. This basic result can be very helpful for tissue engineering.

关键词： Chitosan Degree of deacetylation Biodegradability Cytocompatibility Celladhesion ability Biocompatibility

Forkhead box M1 transcription factor:a novel target for pulmonary arterial hypertension therapy

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World Journal of Pediatrics 2020年第2期16卷 113-119页

作者： Li Gu han-Min liu Department of Pediatric Pneumology West China Second University HospitalSichuan UniversityChengduChina Key Laboratory of Birth Defects and Related Diseases of Women and Children(Sichuan University) Ministry of EducationWest China Second University HospitalSichuan UniversityNo.20Section 3Renmin South RoadWuhou DistrictChengduChina

Background Forkhead box M1(FoxM1),a member of forkhead family,plays a key role in carcinogenesis,progression,invasion,metastasis and drug *** on the similarities between cancer and pulmonary arterial hypertension,studies on the roles and mechanisms of FoxM1 in pulmonary arterial hypertension have been *** article aims to review recent advances in the mechanisms of signal transduction associated with FoxM1 in pulmonary arterial *** sources Articles were retrieved from PubMed and MEDLINE published after 1990,including-but not limited to FoxM1 and pulmonary arterial *** FoxM 1 is overexpressed in pulmonary artery smooth muscle cells in both pulmonary arterial hypertension patients and animal models,and promotes pulmonary artery smooth muscle cell proliferation and inhibits cell apoptosis via regulating cell cycle *** signaling molecules and pathways,including hypoxia-inducible factors,transforming growth factor-β/Smad,SET domain-containing 3/vascular endothelial growth factor,survivin,cell cycle regulatory genes and DNA damage response network,are reported to cross talk with FoxM1 in pulmonary arterial *** inhibitors are effective in the prevention and treatment of pulmonary arterial hypertension by inhibiting the expression and transcriptional activity of *** FoxM1 has a crucial role in the pathogenesis of pulmonary arterial hypertension and may represent a novel therapeutic *** more details of interaction between FoxM1 and other signaling pathways need to be clarified in the future.

关键词： Forkhead box M1 Proteasome inhibitor Pulmonary arterial hypertension Signaling pathway

ABRUPT DEFLECTED SUPERCRITICAL WATER FLOW-REVISED THEORY OF SHOCK WAVE

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Journal of Hydrodynamics 2006年第1期18卷 32-39页

作者： NI han-gen liu Ya-kun State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

The shock wave angle and depth ratio of the abrupt deflected supercritical water flow due to deflector was investigated experimentally and theoretically. A correction coefficient of the hydro-dynamic pressure ξ was introduced to generalize the momentum equation in the perpendicular direction to the shock front. An extensive series of tests were conducted in a 1 m wide flume with the Froude number ranging from 1.70 to 8.37, the deflection angle ranging from 5° to 40° and the length of deflector ranging from 0.28 m to 1 m. A dimensionless parameter K was defined to depict the ratio of the flow height to flow thickness. Test results show that the val ue of ~, the correction coefficient of the non-hydrostatic pres- sure distribution, decreases with the increase of the value of K An empirical relationship between the value of ξ and the val ue of K was proposed. It is indicated that the relative errors of the results calculated by the revised theory is much smaller than that obtained from the Ippen theory. Finally, a simple explicit expression was suggested to calculate the shock wave height ratio in consideration of the effect of the non-hydrostatic pressure distribution.

关键词： theory of shock wave abrupt deflection of supercritical flow trajectory type energy dissipater

Experimental study of lightweight aggregate concrete under multiaxial stresses

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第8期11卷 545-554页

作者： han-yong liu Yu-pu SONG Structural Engineering Institute School of Civil Engineering Faculty of lnfrastructure Engineering Dalian University of Technology Dalian 116024 China

Lightweight aggregate concrete cube specimens (100 mm×100 mm×100 mm) and plate specimens (100 mm×100 mm×50 mm) were tested under biaxial compression-compression (CC) and compression-tension (CT) load combinations. For comparison, normal concrete plate specimens (100 mm×100 mm×50 mm) were tested under the same load combinations. Based on the test results, a two-level strength criterion of lightweight aggregate concrete in both octahedral stress coordinate and principal stress coordinate was suggested. The lightweight aggregate concrete cube specimens (100 mm×100 mm×100 mm) were then tested under triaxial compression-compression-compression (CCC) load combination with corresponding tests on normal concrete cube specimens (100 mm×100 mm×100 mm). The effect of intermediate principal stress on triaxial compressive strength is further examined. A "plastic flow plateau" area was apparent in principal compressive stress-strain relationships of lightweight aggregate concrete but not in normal concrete. A quadratic formula was suggested for the expression of strength criterion under triaxial compression.

关键词： Lightweight aggregate concrete Normal concrete Biaxial loads Triaxial loads Compressive strength Tensile strength Stress-strain relationships Plastic flow plateau Lode angle

Vortex-lines motion for the Ginzburg-Landau equation with impurity

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Science China Mathematics 2007年第12期50卷 1705-1734页

作者： Zu-han liu Department of Mathematics Xuzhou Normal University Xuzhou 221116 China

In this paper, we study the asymptotic behavior of solutions of the Ginzburg-Landau equation with impurity. We prove that, asymptotically, the vortex-lines evolve according to the mean curvature flow with a forcing te... 详细信息

关键词： mean curvature flow, vortices, geometric measure theory, Ginzburg-Landau equations

Time Synchronized Velocity Error for Trajectory Compression

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Computer Modeling in Engineering & Sciences 2022年第2期130卷 1193-1219页

作者： Haibao Jiang Dezhi han han liu Jiuzhang han Wenjing Nie College of Information Engineering ShanghaiMaritime UniversityShanghai201306China College of Foreign Language ShanghaiMaritime UniversityShanghai201306China

Nowadays,distance is usually used to evaluate the error of trajectory *** methods can effectively indicate the level of geometric similarity between the compressed and the raw trajectory,but it ignores the velocity error in the *** fill the gap of these methods,assuming the velocity changes linearly,a mathematical model called SVE(Time Synchronized Velocity Error)for evaluating compression error is designed,which can evaluate the velocity error effectively,conveniently and *** on this model,an innovative algorithm called SW-MSVE(Minimum Time Synchronized Velocity Error Based on Sliding Window)is proposed,which can minimize the velocity error in trajectory compression under the premise of local *** elaborate experiments are designed to demonstrate the advancements of the SVE and the SW-MSVE *** the first experiment,we use the PED,the SED and the SVE to evaluate the error under four compression algorithms,one of which is the SW-MSVE *** results show that the SVE is less influenced by noise with stronger performance and more *** the second experiment,by marking the raw trajectory,we compare the SW-MSVE algorithm with three others algorithms at information *** results show that the SW-MSVE algorithm can take into account both velocity and geometric structure constraints and retains more information of the raw trajectory at the same compression ratio.

关键词： Trajectory compression error evaluation trajectory data time synchronization velocity compression ratio

Uncertainty Analysis for Ship-Bank Interaction Tests in A Circulating Water Channel

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China Ocean Engineering 2020年第3期34卷 352-361页

作者： liu han MA Ning GU Xie-chong School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai Jiao Tong UniversityShanghai 200240China

This paper presents a systematic model test program to assess the uncertainty of the ship-bank interaction forces,using the planar motion mechanism(PMM)system in a circulating water channel(CWC).Therefore,the uncertainties due to ship-bank distance and water depth are considered,and they are calculated via the partial differentials of the regression formulae based on the test *** general part of the uncertainty analysis(UA)is performed according to the ITTC recommended procedure 7.5-02-06.04,while the uncertainty of speed is identified as the bias limit due to the flow velocity maldistribution in the *** each example test for the UA of ship-bank interaction forces,12 repeated measurements were *** from the UA show that the contribution of water depth error and flow velocity maldistribution to the total uncertainty is noticeable,and the paper explains how they increase with the change of the test *** present study will be useful in understanding the uncertainty regarding the ship-bank interaction force measurement in a CWC.

关键词： ship-bank interaction test uncertainty analysis circulating water channel bias limit ship-bank distance

Reducing congestion and emissions via roadside unit deployment under mixed traffic flow

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International Journal of Coal Science & Technology 2023年第1期10卷 197-211页

作者： Yuhao liu Zhibin Chen Siyuan Gong han liu Shanghai Key Laboratory of Urban Design and UrbanScience NYU ShanghaiShanghaiChina Division of Engineering and Computer Science NYUShanghaiShanghaiChina The Joint Laboratory for Internet of Vehicles Ministryof Education-China Mobile Communications CorporationXi’anShaanxiChina School of Information Engineering Chang’an UniversityXi’anShaanxiChina Central Research Institute China Coal Technologyand Engineering Group(CCTEG)BeijingChina

It is expected that for a long time the future road trafc will be composed of both regular vehicles(RVs)and connected autonomous vehicles(CAVs).As a vehicle-to-infrastructure technology dedicated to facilitating CAV under the mixed trafc fow,roadside units(RSUs)can also improve the quality of information received by CAVs,thereby infuencing the routing behavior of CAV *** paper explores the possibility of leveraging the RSU deployment to afect the route choices of both CAVs and RVs and the adoption rate of CAVs so as to reduce the network congestion and *** this end,we frst establish a logit-based stochastic user equilibrium model to capture drivers’route choice and vehicle type choice behaviors provided the RSU deployment plan is ***,CAV users’perception error can be reduced by higher CAV penetration and denser RSUs deployed on the road due to the improved information *** the established equilibrium model,the RSU deployment problem is then formulated as a mathematical program with equilibrium *** active-set algorithm is presented to solve the deployment problem *** results suggest that an optimal RSU deployment plan can efectively drive the system towards one with lower network delay and emissions.

关键词： Roadside unit deployment Connected autonomous vehicle Information quality Congestion and emission

Generation of Interstellar Class Ⅱ 7_2-8_1A^+ and 7_2-8_1A^-Methanol Masers

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Chinese Journal of Astronomy and Astrophysics 2007年第6期7卷 803-808页

作者： han-Ping liu Jin Sun Department of Physics Beijing Normal University Beijing 100875 Department of Astronomy Beijing Normal University Beijing 100875

New methanol maser lines at 72 → 63A^-（86.6 GHz） and 72 → 63A^＋（86.9 GHz） together with two candidate methanol maser lines at 72 → 81A-（80.99GHz） and 72→81A^＋（111.29GHz） have been detected in W3（OH）. We use a pumping mechanism, i.e., methanol masers without population inversion, to explain the formation of weak methanol masers of 72 → 81A^＋ and 72→ 81A^-. We explain well why the line-shape of the transition 72 → 81A^＋ is not typical. A similar argument can be applied to the A-type level system 72A^-, 63A^- and 81A^-, as well as to the 72 → 81A^- 80.99 GHz masers.

关键词： pumping mechanism -- Class II methanol sources -- maser without inversion-- coherent microwave field