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Antioxidant and cardioprotective effects of Ilex cornuta on myocardial ischemia injury

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Chinese Journal of Natural Medicines 2017年第2期15卷 94-104页

作者： YUAN yan pan shu yanG Shi-Lin LIU yan-Li XU Qiong-Ming Department of Pharmacology College of Pharmaceutical ScienceSoochow UniversitySuzhou 215123China Department of Pharmaceutical Chemistry Guizhou UniversityGuiyang 550025China Department of Pharmacognosy College of Pharmaceutical ScienceSoochow UniversitySuzhou 215123China

Previous studies have indicated that the Ilex genus exhibits antioxidant, neuroprotective, hepatoprotective, and antiinflammatory activities. However, the pharmacologic action and mechanisms of Ilex cornuta against cardiac diseases have not yet been explored. The present study was designed to investigate the antioxidant and cardioprotective effects of Ilex cornuta root with in vitro and in vivo models. The anti-oxidative effects of the extract of Ilex cornuta root(ICR) were measured by 2, 2-diphenyl-1- picrylhydrazyl(DPPH) free-radical scavenging and MTT assays as well as immunoassay. Furthermore, a rat model of myocardial ischemia was established to investigate the cardioprotective effect of ICR in vivo. Eight compounds were isolated and identified from ICR and exhibited DPPH free-radical scavenging activities. They also could increase cell viability and inhibit morphological changes induced by H_2O_2 or Na_2S_2O_4 in H9c2 cardiomyocytes, followed by increasing the SOD activities and decreasing the MDA and ROS levels. In addition, it could suppress the apoptosis of cardiomyocytes. In the rat model of myocardial ischemia, ICR decreased myocardial infarct size and suppressed the activities of LDH and CK. Furthermore, ICR attenuated histopathological alterations of heart tissues and the MDA levels, while increasing SOD activities in serum. In conclusion, these results suggest that ICR has cardioprotective activity and could be developed as a new food supplement for the prevention of ischemic heart disease.

关键词： Ilex cornuta Myocardial ischemia Antioxidant Apoptosis

乳腺癌中医证候分型与细胞增殖核抗原表达的相关性研究

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中国卫生检验杂志 2017年第4期27卷 502-504页

作者：傅春燕陈述政潘颖郑琎蔡仕彬潘聪慧丽水市中心医院甲状腺乳腺外科浙江丽水323000

目的探讨乳腺癌中医证候分型与细胞增殖核抗原Ki-67表达的相关性。方法对180例乳腺癌患者在手术前及其他治疗前均进行中医辨证分型,检测Ki-67表达情况,并进行相关性分析。结果研究对象乳腺癌中医分型以肝淤痰凝型为最多,占53.33%,冲任... 详细信息

目的探讨乳腺癌中医证候分型与细胞增殖核抗原Ki-67表达的相关性。方法对180例乳腺癌患者在手术前及其他治疗前均进行中医辨证分型,检测Ki-67表达情况,并进行相关性分析。结果研究对象乳腺癌中医分型以肝淤痰凝型为最多,占53.33%,冲任失调型次之,占24.44%,正虚毒炽型最低,占22.23%;Ki-67阴性表达为35.56%,低于阳性表达(64.44%);乳腺癌中医证候分型与Ki-67表达为正相关关系(r=0.219,P<0.01),正虚毒炽型乳腺癌患者的Ki-67阳性表达明显高于冲任失调型及肝淤痰凝型,以肝淤痰凝型乳腺癌患者的Ki-67阳性表达为最低。结论乳腺癌中医证候分型与Ki-67表达为正相关关系,所以中医的辨证论治可以预测乳腺癌的预后情况,并为辨证施治提供理论依据。

关键词：乳腺癌中医证候分型细胞增殖核抗原相关性研究

Simulations and Projections of Winter Sea Ice in the Barents Sea by CMIP6 Climate Models

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Advances in Atmospheric Sciences 2023年第12期40卷 2318-2330页

作者： Rongrong pan Qi shu Zhenya SONG Shizhu WANG yan HE Fangli QIAO First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdao 266061China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Dramatic changes in the sea ice characteristics in the Barents Sea have potential consequences for the weather and climate systems of mid-latitude continents,Arctic ecosystems,and fisheries,as well as Arctic maritime *** and projections of winter sea ice in the Barents Sea based on the latest 41 climate models from the Coupled Model Intercomparison Project Phase 6(CMIP6)are investigated in this *** show that most CMIP6 models overestimate winter sea ice in the Barents Sea and underestimate its decreasing *** discrepancy is mainly attributed to the simulation bias towards an overly weak ocean heat transport through the Barents Sea Opening and the underestimation of its increasing *** methods of observation-based model selection and emergent constraint were used to project future winter sea ice changes in the Barents *** indicate that sea ice in the Barents Sea will continue to decline in a warming climate and that a winter ice-free Barents Sea will occur for the first time during 2042-2089 under the Shared Socioeconomic Pathway 585(SSP5-8.5).Even in the observation-based selected models,the sensitivity of winter sea ice in the Barents Sea to global warming is weaker than observed,indicating that a winter ice-free Barents Sea might occur earlier than projected by the CMIP6 simulations.

关键词： Arctic sea ice Barents Sea ocean heat transport sea ice projection CMIP6

On the micromechanism of superior strength and ductility synergy in a heterostructured Mg-2.77Y alloy

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Journal of Magnesium and Alloys 2024年第7期12卷 2793-2811页

作者： Yuliang yang Yuxin Liu shu yan shuang Jiang Zhufeng He Haizheng pan Nan Jia Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Key Laboratory of Lightweight Structural Materials Northeastern UniversityShenyang 110819China

Heterostructured metals and alloys are a new class of materials in which mechanical behaviors between the heterogeneous regions are significantly different,and the mechanical properties of bulk materials are superior to the superposition of individual *** this paper,three distinct types of heterostructures were constructed in Mg-2.77Y(wt.%)alloy by applying simple thermomechanical ***,Type I:the non-recrystallized grains of several tens of microns were embedded in the micron-scaled recrystallized grains that were distributed along shear bands and dispersed near grain boundaries;Type II:the aggregations of micron-scaled recrystallized grains were surrounded by the non-recrystallized grains;Type II:the micron-scaled recrystallized grains dominated the microstructure,and the non-recrystallized regions with diameters of tens of micrometers were surrounded by those fine recrystallized *** tests showed that the material with type III heterostructure had the optimal combination of yield strength and uniform *** is attributed to its remarkable hetero-deformation induced(HDI)strengthening and dislocation *** the initial stage of plastic deformation(engineering strain below 4%),the rapid accumulation of geometrically necessary dislocations(GNDs)at the interfaces between recrystallized and non-recrystallized regions and between neighboring recrystallized grains lead to the significant HDI *** deformation proceeded,the HDI strengthening effect gradually decreased,and the traditional dislocation strengthening that was caused by GNDs accumulation at grain boundaries became ***-situ electron back-scattered diffraction(EBSD)testing revealed that the non-basal slip in the non-recrystallized regions became more remarkable in the late stage of deformation,which improved ductility and strain hardening of the *** findings provide new insight into the design of high-performance hexagonal close-pac

关键词： Heterostructure Magnesium alloy Hetero-deformation induced strengthening In-situ EBSD

Recent advances in self-propelled particles

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Science China Chemistry 2017年第10期60卷 1293-1304页

作者： Qi pan yan He Department of Chemistry Tsinghua University Beijing 100084 China

"Active" components can be introduced into a passive system to completely change its physical behavior from its typical behavior at thermodynamic equilibrium. To reveal the interaction mechanisms between individuals, researchers have designed unique self-propelled particles to mimic the collective behavior of biological systems. This review focuses on recent theoretical and experimental advances in the study of self-propelled particle systems and their individual and collective behaviors. The potential applications of active particles in chemical, biological and environmental sensing and single particle imaging are discussed.

关键词： self-propelled particles micromotors collective behavior single particle tracking

Characteristics of anoxic phosphors removal in sequence batch reactor

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Journal of Environmental Sciences 2007年第7期19卷 776-782页

作者： WANG Ya-yi pan Mian-li yan Min PENG Yong-zhen WANG shu-ying College of Civil Engineering and Architecture Zhejiang University of Technology Hangzhou 310014 China. Key Lab of Beijing for Water Quality Science Beijing University of Technology Beijing 100022 China Biotech Institute Hangzhou Huadong Medicine Group Co. Ltd Hangzhou 310011 China

The characteristics of anaerobic phosphorus release and anoxic phosphorus uptake were investigated in sequencing batch reactors using denitrifying phosphorus removing bacteria （DPB） sludge. The lab-scale experiments were accomplished under conditions of various nitrite concentrations （5.5, 9.5, and 15 mg/L） and mixed liquor suspended solids （MLSS）（1844, 3231, and 6730 mg/L）. The results obtained confirmed that nitrite, MLSS, and pH were key factors, which had a significant impact on anaerobic phosphorus release and anoxic phosphorus uptake in the biological phosphorous removal process. The nitrites were able to successfully act as electron acceptors for phosphorous uptake at a limited concentration between 5.5 and 9.5 mg/L. The denitrification and dephosphorous were inhibited when the nitrite concentration reached 15 mg/L. This observation indicated that the nitrite would not inhibit phosphorus uptake before it exceeded a threshold concentration. It was assumed that an increase of MLSS concentration from 1844 mg/L to 6730 mg/L led to the increase of denitrification and anoxic P-uptake rate. On the contrary, the average P-uptake/N denitrifying reduced from 2.10 to 1.57 mg PO4^3--P/mg NO3^--N. Therefore, it could be concluded that increasing MLSS of the DEPHANOX system might shorten the reaction time of phosphorus release and anoxic phosphorus uptake. However, excessive MLSS might reduce the specific denitrifying rate. Meanwhile, a rapid pH increase occurred at the beginning of the anoxic conditions as a result of denitrification and anoxic phosphate uptake. Anaerobic P release rate increased with an increase in pH. Moreover, when pH exceeded a relatively high value of 8.0, the dissolved P concentration decreased in the liquid phase, because of chemical precipitation. This observation suggested that pH should be strictly controlled below 8.0 to avoid chemical precipitation if the biological denitrifying phosphorus removal capability is to be studied accurately.

关键词： biological phosphorus removal nitrite MLSS pH denitrifying phosphorus removing bacteria (DPB) anaerobic-anoxic processes

Research status and performance optimization of medium-temperature thermoelectric material SnTe

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Chinese Physics B 2022年第4期31卷 18-30页

作者： pan-pan Peng Chao Wang Lan-Wei Li shu-Yao Li yan-Qun Chen Institute for Computational Materials Science School of Physics and ElectronicsHenan UniversityKaifeng 475004China

Thermoelectric materials have the ability to directly convert heat into electricity,which have been extensively studied for decades to solve global energy shortages and environmental *** a medium temperature(400-800 K)thermoelectric material,SnTe has attracted extensive attention as a promising substitute for PbTe due to its non-toxic *** this paper,the research status of SnTe thermoelectric materials is reviewed,and the strategies to improve its performance are summarized and discussed in terms of electrical and thermal transport *** comprehensive discussion will provides guidance and inspiration for the research on SnTe.

关键词： SnTe thermoelectric materials electronic transport thermal conductivity

Joint offloading strategy based on quantum particle swarm optimization for MEC-enabled vehicular networks

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Digital Communications and Networks 2023年第1期9卷 56-66页

作者： Wanneng shu yan Li College of Computer Science South-Central University for NationalitiesWuhan430074China College of Science Huazhong Agricultural UniversityWuhan430070China

With the development of the mobile communication technology,a wide variety of envisioned intelligent transportation systems have emerged and put forward more stringent requirements for vehicular *** of computation-intensive and power-hungry applications result in a large amount of energy consumption and computation costs,which bring great challenges to the on-board *** is necessary to exploit traffic offloading and scheduling in vehicular networks to ensure the Quality of Experience(QoE).In this paper,a joint offloading strategy based on quantum particle swarm optimization for the Mobile Edge Computing(MEC)enabled vehicular networks is *** minimize the delay cost and energy consumption,a task execution optimization model is formulated to assign the task to the available service nodes,which includes the service vehicles and the nearby Road Side Units(RSUs).For the task offloading process via Vehicle to Vehicle(V2V)communication,a vehicle selection algorithm is introduced to obtain an optimal offloading decision ***,an improved quantum particle swarm optimization algorithm for joint offloading is proposed to optimize the task delay and energy *** maintain the diversity of the population,the crossover operator is introduced to exchange information among ***,the crossover probability is defined to improve the search ability and convergence speed of the ***,an adaptive shrinkage expansion factor is designed to improve the local search accuracy in the later *** results show that the proposed joint offloading strategy can effectively reduce the system overhead and the task completion delay under different system parameters.

关键词： Computation offloading MEC-enabled vehicular networks Mobile edge computing Task scheduling

Investigation of vortical flow over bluff bodies with base cavities

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Acta Mechanica Sinica 2012年第5期28卷 1238-1247页

作者： shu-Cheng pan Jin-Sheng Cai National Key Laboratory of Aerodynamic Design and Research Northwestern Polytechnical University

Based on our previous research about drag reduction in term of the base cavity length using two dimensional simulations, this paper describes a numerical study of a bluff body of which the number of base cavities is successively increased and the cavity geometries are also modified to assume different shapes. Here we attempt to find an effective configuration to reduce the drag by increasing the number of base cavities. The numerical simulations examining varied number of base cavities reveal the presence of different strength of vortices in the wake zone which is the reason why the drag coefficients are distinctly different for different cases. In the case with double and triple rectangular cavities, we use the pressure contours snapshots at successive time instants to describe the wake evolution. We further investigate the effect of variable base cavity shapes for a constant cavity length at an identical time instant. A total of two different geometries of base cavities are discussed here： the rectangular and the sinusoidal cavities with sharp and rounded trailing edges, respectively. The numerical results reveal that the for- mer is an effective drag reduction configuration which can produce a significant base pressure recovery corresponding to the strength of the vortices shown in the pressure contour figures. While the latter shows no obvious reduction in drag coefficient and a similar intensity of vortex in the wake zone compared with the unmodified case. Reductions in drag are observed for all the investigated cavity configurations, and additionally it is found that the magnitude of the reduction bears a direct relationship with the number of the cavities up to a certain minimum value.

关键词： Flow control Drag reduction. Bluff body Basecavity