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| 1 | SlMYB75,an MYB-type transcription factor,promotes anthocyanin accumulation and enhances volatile aroma production in tomato fruits显示文摘Genetic manipulation of genes to upregulate specific branches of metabolic pathways is a method that is commonly used to improve fruit quality.However,the use of a single gene to impact several metabolic pathways is difficult.Here,we show that overexpression of the single gene SlMYB75(SlMYB75-OE)is effective at improving multiple fruit quality traits.In these engineered fruits,the anthocyanin content reached 1.86mg g−1 fresh weight at the red-ripe stage,and these SlMYB75-OE tomatoes displayed a series of physiological changes,including delayed ripening and increased ethylene production.In addition to anthocyanin,the total contents of phenolics,flavonoids and soluble solids in SlMYB75-OE fruits were enhanced by 2.6,4,and 1.2 times,respectively,compared to those of wild-type(WT)fruits.Interestingly,a number of aroma volatiles,such as aldehyde,phenylpropanoid-derived and terpene volatiles,were significantly increased in SlMYB75-OE fruits,with some terpene volatiles showing more than 10 times higher levels than those in WT fruits.Consistent with the metabolic assessment,transcriptomic profiling indicated that the genes involved in the ethylene signaling,phenylpropanoid and isoprenoid pathways were greatly upregulated in SlMYB75-OE fruits.Yeast one-hybrid and transactivation assays revealed that SlMYB75 is able to directly bind to the MYBPLANT and MYBPZM cis-regulatory elements and to activate the promoters of the LOXC,AADC2 and TPS genes.The identification of SlMYB75 as a key regulator of fruit quality attributes through the transcriptional regulation of downstream genes involved in several metabolic pathways opens new avenues towards engineering fruits with a higher sensory and nutritional quality. | Wei Jian Haohao Cao Shu Yuan Yudong Liu Juanfang Lu Wang Lu Ning Li Jianhui Wang Jian Zou Ning Tang Chan Xu Yulin Cheng Yanqiang Gao Wanpeng Xi Mondher Bouzayen Zhengguo Li | 2019 | Horticulture Research2019，6，1： | 39 |
| 2 | Geochronology of Baogutu porphyry copper deposit in Western Junggar area, Xinjiang of China显示文摘Baogutu copper deposit in Western Junggar area is a mesoscopic porphyry deposit found in recent years. Study on its geochronology will help further understand ore genesis and regional ore-forming pattern. A series of small quartz-diorite and granodiorite stocks outcrop at Baogutu area, numbered I―X according to their size. A detailed exploration on Number V stock confirmed it as a mesoscopic scale copper deposit, and various exploration work has been carried out on other stocks with ore-forming evidence. This paper studies geochronology of Number V stock using zircon SHRIMP U-Pb and single mineral K-Ar method. Twenty-five SHRIMP ages yield two 206Pb/238U weighed mean ages of 335.6 ± 7.8 Ma and 311.4 ± 3.3 Ma respectively. The older date is considered to be inherited zircon from either surrounding rock tuff or deep granitoid batholith, whereas the younger date is the formation age of ore-bearing intrusion. K-Ar ages of ore-forming biotites, 296.0 ± 3.7 Ma and 297.3 ± 3.8 Ma, in combination with Re-Os age of molybdenite, 310 Ma, confirm the ore-forming age of 310-296 Ma. Granophyre and dioritic porphyrite dikes cut Number V stock and their K-Ar ages range from 278 to 240 Ma, which confine the lower boundary of the mineralization. The framework of Baogutu ore-forming geochrono-logy can be established based on these data. | LIU YuLin GUO LiShuang LIU YuDe SONG HuiXia SONG Biao ZHANG Rui XU FaJun ZHANG YunXiao | 2009 | Science China Earth Sciences2009，52，10： | 33 |
| 3 | PIV measurement on internal instantaneous flows of a centrifugal pump显示文摘In this paper,the internal flow field in a centrifugal pump working at the design flow rate operating condition has been measured using the particle image velocimetry(PIV)technique with the fluorescent particles and the index-matched fluid technology.The index-marching fluid with the same refractive index as the transparent material has been prepared and applied in the present test of pump with geometrical complex walls.The comparison between velocity distributions of PIV results both with and without fluorescent particles,as well as with and without index-marching fluid are conducted to find the differences.The DES(Detached Eddy Simulation)has been employed to calculate the three-dimensional unsteady turbulent flow in the pump to examine and to certify the PIV measurement results.The DES results of instantaneous flow velocity fields agree with PIV test results with fluorescent particles and index-marching fluid.It is necessary to perform the PIV measurement of pumps with fluorescent seeds and index-marching fluid in order to get exact results.The experimental results show the distributions of velocity,steamlines,and the principal Reynolds normal stress(PRNS)and the principal Reynolds shear stress(PRSS). | WU YuLin LIU ShuHong YUAN HuiJing SHAO Jie | 2011 | Science China(Technological Sciences)2011，54，2： | 20 |
| 4 | An optimization method on runner blades in bulb turbine based on CFD analysis显示文摘In this paper an optimization method of the runner blades in a bulb turbine based on CFD analysis is proposed.In the method the main scales of the turbine including guide vane,runner and draft are maintained.Only the runner blades are modified based on the present method.In the optimization method the runner blade is expressed by spline surface with a gather of coordinate points.The B-spline curve is used to keep the modified blades smooth.In order to make the blade optimization simple and ef- ficient,one of the coordinates is fixed and only the angles of the points are changed according to different modification purposes.Three main optimization principles based on flow diagnosis are presented here.These three principles are all based on the CFD analysis of the internal flow in bulb turbine.For the purpose of method verification,the optimization method is used in a model bulb turbine.A three dimensional steady turbulent computation is carried out through the whole passage including the bulb body,guide vanes,runner and draft tube of the bulb turbine under seven different work conditions.An SST k-ωturbulence model is used during the CFD analysis and the performance of the turbine can be achieved.The runner blade is optimized according to the three optimization principles based on flow diagnosis.The CFD analysis is conducted again on the optimized turbine and another modification is needed if the new turbine can’t satisfy the required performance.Comparison of the computational results between the original turbine and an optimized one indicates that the optimization method is practical and does improve the performance of the bulb turbine. | YANG Wei WU YuLin LIU ShuHong | 2011 | Science China(Technological Sciences)2011，54，2： | 15 |
| 5 | Biofunctional magnesium coated Ti6Al4V scaffold enhances osteogenesis and angiogenesis in vitro and in vivo for orthopedic application显示文摘The insufficient osteogenesis and osseointegration of porous titanium based scaffold limit its further application.Early angiogenesis is important for scaffold survival.It is necessary to develop a multifunctional surface on titanium scaffold with both osteogenic and angiogenic properties.In this study,a biofunctional magnesium coating is deposited on porous Ti6Al4V scaffold.For osseointegration and osteogenesis analysis,in vitro studies reveal that magnesium-coated Ti6Al4V co-culture with MC3T3-E1 cells can improve cell proliferation,adhesion,extracellular matrix(ECM)mineralization and ALP activity compared with bare Ti6Al4V cocultivation.Additionally,MC3T3-E1 cells cultured with magnesium-coated Ti6Al4V show significantly higher osteogenesisrelated genes expression.In vivo studies including fluorochrome labeling,micro-computerized tomography and histological examination of magnesium-coated Ti6Al4V scaffold reveal that new bone regeneration is significantly increased in rabbits after implantation.For angiogenesis studies,magnesium-coated Ti6Al4V improve HUVECs proliferation,adhesion,tube formation,wound-healing and Transwell abilities.HUVECs cultured with magnesium-coated Ti6Al4V display significantly higher angiogenesis-related genes(HIF-1αand VEGF)expression.Microangiography analysis reveal that magnesium-coated Ti6Al4V scaffold can significantly enhance the blood vessel formation.This study enlarges the application scope of magnesium and provides an optional choice to the conventional porous Ti6Al4V scaffold with enhanced osteogenesis and angiogenesis for further orthopedic applications. | Peng Gao Bo Fan Xiaoming Yu Wenwen Liu Jie Wu Lei Shi Di Yang Lili Tan Peng Wan Yulin Hao Shujun Li Wentao Hou Ke Yang Xiaokang Li Zheng Guo | 2020 | Bioactive Materials2020，5，3： | 15 |
| 6 | The late Paleoproterozoic extension event:aulacogens and dyke Swarms in the North China craton显示文摘在北方中国 Craton (NCC ) 的延期结构和构造牵连基于 mafic 塘群和地球年代学在这篇论文被讨论,与 aulacogens 的地球年代学结合。迟了的 Paleoproterozoic 时间是在 NCC 的前寒武纪的进化的重要拐弯处点。延期系统(例如 aulacogens 和塘群) 在 NCC 是普遍的,它与类似于现代的板的僵硬特征标记 NCC 的碳化。当模特儿的 paleostress 地建议塘聚集, aulacogens 是标记超级大陆,不是 synorogenic 的开始的 arogenic 扩展和 postorogenic 扩展。在 NCC 的 mafic 塘群主要从 1.83 ~ 1.77 Ga 。NCC 的延期是很有限的易碎的扩展,平均延期比率仅仅是 0.35% 由 mafic 塘群延期计算给,大多数在 NCC 的扩展被 aulacogens 因此贡献。mafic 塘群在起源与 aulacogens 被联系。 | HOU Guiting LI Jianghai LIU Yulin QIAN Xianglin | 2006 | Progress in Natural Science:Materials International2006，16，2： | 13 |
| 7 | Progress and records in the study of endogenetic mineralization during collisional orogenesis显示文摘To develop and perfect the theory of plate tectonics and regional metallogeny, metal-logenesis during collisional orogenesis should be thoroughly studied and will attract increasing at-tention of more and more scientists. This paper presents the main aspects of research and discus-sions on metallogenesis during collisional orogenesis after the development of plate tectonics, and accordingly divides the study history into two stages, i.e. the junior stage during 1971-1990 and the senior stage after 1990. Beginning with the negation of mineralization in the collision regime by Guild (1971), the focus of study was put on whether there occurred any mineralization during collisional orogenesis at the junior stage. At the senior stage, which is initiated by the advance of met-allogenic and petrogenic model for collisional orogenesis, scientists begin to pay their attention to the geodynamic mechanism of metallogenesis, spatial and temporal distribution of ore deposits, ore-forming fluidization, relationship | Yanjing Chen Huayong Chen Yulin Liu Guangjun Guo Yong Lai Shan Qin Baoling Huang Zengjie Zheng Yinghui Sui Chao Li et al. | 2000 | Chinese Science Bulletin2000，45，1： | 13 |
| 8 | Metamodel-based Global Optimization Using Fuzzy Clustering for Design Space Reduction显示文摘High fidelity analysis are utilized in modern engineering design optimization problems which involve expensive black-box models.For computation-intensive engineering design problems,efficient global optimization methods must be developed to relieve the computational burden.A new metamodel-based global optimization method using fuzzy clustering for design space reduction(MGO-FCR) is presented.The uniformly distributed initial sample points are generated by Latin hypercube design to construct the radial basis function metamodel,whose accuracy is improved with increasing number of sample points gradually.Fuzzy c-mean method and Gath-Geva clustering method are applied to divide the design space into several small interesting cluster spaces for low and high dimensional problems respectively.Modeling efficiency and accuracy are directly related to the design space,so unconcerned spaces are eliminated by the proposed reduction principle and two pseudo reduction algorithms.The reduction principle is developed to determine whether the current design space should be reduced and which space is eliminated.The first pseudo reduction algorithm improves the speed of clustering,while the second pseudo reduction algorithm ensures the design space to be reduced.Through several numerical benchmark functions,comparative studies with adaptive response surface method,approximated unimodal region elimination method and mode-pursuing sampling are carried out.The optimization results reveal that this method captures the real global optimum for all the numerical benchmark functions.And the number of function evaluations show that the efficiency of this method is favorable especially for high dimensional problems.Based on this global design optimization method,a design optimization of a lifting surface in high speed flow is carried out and this method saves about 10 h compared with genetic algorithms.This method possesses favorable performance on efficiency,robustness and capability of global convergence and gives a new optimization strategy for engineering design optimization problems involving expensive black box models. | LI Yulin LIU Li LONG Teng DONG Weili | 2013 | Chinese Journal of Mechanical Engineering2013，26，5： | 13 |
| 9 | Discovery of mantle and lower crust xenoliths from early Cretaceous volcanic rocks of southwestern Tianshan,Xinjiang显示文摘In Tuoyun area of southwestern Tianshan, mantle and lower crust xenoliths are present In the volcanic rocks with ages of 101-123 Ma. Mantle xenoliths include mineral megacrysts such as kaersutite and pargasite, feldspar, biotite, and rare pyroxene and rock fragments such as perodotite, pyroxenite, amphibolite, and rare glimmerite. Lower crust xenoliths are mainly banded and massive granulite. The volcanic rocks were produced by within-plate magmatism. Occurrence of hydrous and volatile mineral megacrysts, amphibolite, and some pyroxenite containing hydrous and volatile minerals indicates that mantle metasomatism was intense. Undoubtedly, this discovery is very important to understanding of the crust-mantle structure and geodynamic background in depth in southwestern Tianshan and geological correlation with adjacent regions. | Baofu Han Xuechao Wang Guoqi He Tairan Wu Maosong Li Yulin Liu Shiguang Wang | 1999 | Chinese Science Bulletin1999，44，12： | 11 |
| 10 | Distribution of ground stress on Puhe Coal Mine显示文摘Puhe Coal Mine is a typical Tertiary coal in Shenbei mining area. With an increase in mining depth, tectonic stress field becomes more complex, leading to increased deformation and failure of the soft rock roadway. Stress becomes an important factor of mine safety and stability. This paper analyzes the distribution of the regional tectonic field, and determines the distribution of situ stress measurement through measuring the ground stress field in the main mining area level of Puhe Coal Mine using stress relief method. The acquired in situ stress data at different locations and depths provide a reference for the rational arrangement of the stop and mine roadway supporting design, which are of great significance for the efficient safety production of the mine. | Guo Zhibiao Jiang Yulin Pang Jiewen Liu Jiawei | 2013 | International Journal of Mining Science and Technology2013，23，1： | 10 |
| 11 | Cotton bollworm resistance to Bt transgenic cotton: A case analysis显示文摘Cotton bollworm (Helicoverpa armigera) is one of the most serious insect pests of cotton. Transgenic cotton expressing Cry toxins derived from a soil bacterium, Bacillus thuringiensis (Bt), has been produced to target this pest. Bt cotton has been widely planted around the world, and this has resulted in efficient control of bollworm populations with reduced use of synthetic insecticides. However, evolution of resistance by this pest threatens the continued success of Bt cotton. To date, no field populations of bollworm have evolved significant levels of resistance; however, several laboratory-selected Cry-resistant strains of H. armigera have been obtained, which suggests that bollworm has the capacity to evolve resistance to Bt. The development of resistance to Bt is of great concern, and there is a vast body of research in this area aimed at ensuring the continued success of Bt cotton. Here, we review studies on the evolution of Bt resistance in H. armigera, focusing on the biochemical and molecular basis of Bt resistance. We also discuss resistance management strategies, and monitoring programs implemented in China, Australia, and India. | LIU ChenXi, LI YunHe, GAO YuLin, NING ChangMing & WU KongMing State Key Laboratory of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing 100193, China | 2010 | Science China(Life Sciences)2010，53，8： | 10 |
| 12 | Cascade conditional generative adversarial nets for spatial-spectral hyperspectral sample generation显示文摘Sample generation is an effective way to solve the problem of the insufficiency of training data for hyperspectral image classification.The generative adversarial network(GAN)is one of the popular deep learning methods,which utilizes adversarial training to generate the region of samples based on the required class label.In this paper,we propose cascade conditional generative adversarial nets for hyperspectral image complete spatial-spectral sample generation,named C2GAN.The C2GAN includes two stages.The stageone model consists of the spatial information generation with a window size that entails feeding random noise and the required class label.The second stage is the spatial-spectral information generation that generates spectral information of all bands in the spatial region by feeding the label regions.The visualization and verification of generated samples based on the Pavia University and Salinas datasets show superior performance,which demonstrates that our method is useful for hyperspectral image classification. | Xiaobo LIU Yulin QIAO Yonghua XIONG Zhihua CAI Peng LIU | 2020 | Science China(Information Sciences)2020，63，4： | 9 |
| 13 | Electron Beam Melted Beta-type Ti–24Nb–4Zr–8Sn Porous Structures With High Strength-to-Modulus Ratio显示文摘Electron beam melting(EBM)has been used to manufactureβ-type Ti–24Nb–4Zr–8Sn porous components with 70%porosity.EBM-produced components have favorable structural features(i.e.smooth strut surfaces,fewer defects)and an(α+β)-type microstructure,similar to that subjected to aging treatment.EBM-produced components exhibit more than twice the strength-to-modulus ratio of porous Ti–6Al–4V components having the same porosity.The processing–microstructure–property relationship and deformation behavior of EBM-produced components are discussed in detail.Such porous titanium components composed of non-toxic elements and having high strength-to-modulus ratio are highly attractive for biomedical applications. | Yujing Liu Shujun Li Wentao Hou Shaogang Wang Yulin Hao Rui Yang Timothy B.Sercombe Lai-Chang Zhang | 2016 | Journal of Materials Science & Technology2016，32，6： | 9 |
| 14 | Numerical simulation of pressure fluctuation in Kaplan turbine显示文摘As it is almost impossible to carry out the prototype hydro-turbine experiment be- fore the power plant is built up, rational prediction of pressure fluctuations in the prototype turbine is very important at the design stage. From this viewpoint, we at first treated the unsteady turbulent flow computation based on the modified RNG k-ε turbulence model through the whole flow passage to simulate the pressure fluctuation in a model turbine. Since fair agreement was recognized between the numerical results and the experimental data, this numerical method was applied to simulate the pressure fluctuations in the prototype turbine. From the comparison of them with the model turbine results, it is seen that their qualitative trend of pres- sure fluctuations are similar, but an appreciable difference is observed between the amplitudes of pressure fluctuation of the prototype turbine and that of the model turbine. Though the present findings may be explained by the effect of Reynolds number, further studies are expected for quantitative interpretation. We paid atten- tion to the interaction between the fluid and turbine structure. Adopting a weak fluid-solid coupling method, we studied the pressure fluctuation in the prototype turbine to clarify how the elastic behavior of runner blades influenced the charac- teristics of pressure fluctuation. | LIU ShuHong SHAO Jie WU ShangFeng WU YuLin | 2008 | Science China(Technological Sciences)2008，51，8： | 9 |
| 15 | Coupled modeling and analysis of radiometer effect and residual gas damping on proof mass in purely gravitational orbit显示文摘Spacecrafts free of all but gravitational forces are important in precision navigation,gravity field measurement and basic scientific research.The Inner-formation Flying System,one kind of spacecrafts free of all but gravitational forces,is used for gravitational field measurement with high precision.Restraining the interfering factors on the inner-satellite is one of the keys to gravitational field measurement.Radiometer effect and residual gas damping are both interfering forces on the inner-satellite caused by gas molecules.By analyzing the mechanism of the two forces,a coupled model for radiometer effect and residual gas damping was established,which contained the coupling term and reflected the actual force of gas molecules on the inner-satellite.The simulation results showed the coupling property of radiometer effect and residual gas damping:The actual force of gas molecules is directly proportional to the average pressure in the cavity and the largest cross-sectional area of the inner-satellite,but is inversely proportional to the square root of the average temperature in the cavity. | LIU HongWei WANG ZhaoKui ZHANG YuLin | 2011 | Science China(Technological Sciences)2011，54，4： | 8 |
| 16 | Effect of Fe, Si and Cooling Rate on the Formation of Fe-and Mn-rich Intermetallics in Al–5Mg–0.8Mn Alloy显示文摘The Fe-and Mn-rich intermetallics are of great effect on the mechanical properties of the AA5083 type alloy(Al–5Mg–0.8Mn). The effect of Fe, Si and cooling rate on the formation of the intermetallics were investigated by analyzing the microstructures of the alloys with different Fe and Si contents. The results indicated that increasing the Fe content resulted in the increase of the Al_6(Fe,Mn) phase in both amount and size. In the alloys with high Fe content, the platelet-like Al_6(Fe,Mn) compounds lined up and formed a band. Increasing the content of Si resulted in the increase of the Mg_2 Si phase which formed a network structure. Increasing the cooling rate significantly refined the intermetallics. However, increasing the cooling rate did not change the characteristic of the intermetallic compounds in the alloys with low or medium Si contents. For the alloys with high contents of Fe and Si under the condition of near-rapid cooling, the Fe- and Mn-rich intermetallic compound changed to the quaternary (Al)_15(Fe,Mn)_3Si phase and displayed a fine fish bone or Chinese script structure. The refinement of the intermetallics would allow higher tolerance of Fe and Si contents in the AA5083 alloy produced, for instance, via the continuous strip casting process. | Yulin Liu Lei Luo Chaofei Han Liangyun Ou Jijie Wang Chunzhong Liu | 2016 | Journal of Materials Science & Technology2016，32，4： | 7 |
| 17 | Influence of olivine grains on K-Ar dating of Late-Cenozoic olivine basalts in eastern China显示文摘Five Late-Cenozoic olivine basalt samples, taken from 3 young volcanoes (Keluo, Lianhuashan and Qinglongshan) located in the north of Heilongjian Province, were dated by the conventional K-Ar dating method. The apparent ages of whole rock are (0.06±0.01) Ma,( 0.15±0.03) Ma, (0.17±0.02) Ma, (21.10±0.13) Ma and (24.46±0.10) Ma, respectively. In the crushed sample grains (mush number 80-100)olivine(including phynocryst and xenocryst)was picked out under a binocular microscope, then apparent ages obtained are (0.03±0.01) Ma, (0.06±0.01) Ma, (0.07±0.03) Ma, (2.31±0.02) Ma and (1.50±0.21) Ma, respectively. The apparent ages of the olivine-picked out sample are come down (younger)50 to over 90. There are a lot of the Late-Cenozoic volcanic olivine basalt outcropping in eastern China, probably the age-datings of those basalt samples in which olivine grains are unpicked out are older than the true geological ages. The inference and conclusion drawn from those datings should be renewed. | Zhiguo Mu Yulin Liu Baoling Huang | 1998 | Chinese Science Bulletin1998，43，19： | 7 |
| 18 | Overview of Biomass Conversion to Electricity and Hydrogen and Recent Developments in Low-Temperature Electrochemical Approaches显示文摘Biomass is plant or animal material that stores both chemical and solar energies,and that is widely used for heat production and various industrial processes.Biomass contains a large amount of the element hydrogen,so it is an excellent source for hydrogen production.Therefore,biomass is a sustainable source for electricity or hydrogen production.Although biomass power plants and reforming plants have been commercialized,it remains a difficult challenge to develop more effective and economic technologies to further improve the conversion efficiency and reduce the environmental impacts in the conversion process.The use of biomass-based flow fuel cell technology to directly convert biomass to electricity and the use of electrolysis technology to convert biomass into hydrogen at a low temperature are two new research areas that have recently attracted interest.This paper first briefly introduces traditional technologies related to the conversion of biomass to electricity and hydrogen,and then reviews the new developments in flow biomass fuel cells(FBFCs)and biomass electrolysis for hydrogen production(BEHP)in detail.Further challenges in these areas are discussed. | Wei Liu Congmin Liu Parikshit Gogoi Yulin Deng | 2020 | Engineering2020，6，12： | 7 |
| 19 | Residents’ perspectives and responses to environmental degradation in the upper Dadu River, eastern Tibetan Plateau显示文摘Environmental degeneration in the Tibetan Plateau attracts worldwide attention, whereas case studies on how the residents understand and respond to environmental degeneration are scarce. Using a Participatory Rural Appraisal method, this paper investigates how the people in different regions in the upper Dadu River understand and respond to environmental degeneration, based on comparative field surveys in three villages, in which Danzamu village is chosen from villages in the valley region, Kerma village from mountainside region, Rico village from the mountain and plateau region. The results show that: (1) although awakened to environmental degeneration, the residents in different regions have different responses. As agricultural labors have been transferred to the secondary and tertiary industries, population pressure in Danzamu and Kerma villages is mitigated. Residents in Danzamu village actively respond to natural disasters and forest degradation, as their livelihoods never rely on forests and rangelands again. Whereas the residents in Kerma village negatively respond to natural disasters, forest and meadow degradation and the ruin of wildlife resources, as their livelihoods still rely on stockbreeding. Labors in Rico village are hard to transfer to the secondary and tertiary industries, so they have to raise more livestock to make a living. Active measures are just taken to avoid livestock loss, not to avoid forest and meadow degradation and the ruin of wildlife resources. So the most fragile region is the mountain and plateau region and mountainside region, not the valley region. (2) Livelihood strategy is the key factor affecting the residents to respond to population pressure and environmental degeneration. So the framework of sustainable livelihood strategy should be used to explain and intervene in issues of population pressure and environmental degradation in ecotones. (3) Transferring agricultural labors to the secondary and tertiary industries were favorable to improving people’s livelihood. It is necessary to reduce the education fees to speed up the pace of labors transferring in the mountainside region. In the mountain and plateau region, preferable ways also include the development of towns, highways, education equipment and other establishments. | YAN Jianzhong ZHANG Yili LIU Linshan BAI Wanqi ZHU Huiyi SHI Yulin ZHENG Du | 2006 | Journal of Geographical Sciences2006，16，3： | 7 |
| 20 | Improved activity of MC3T3-E1 cells by the exciting piezoelectric BaTiO_(3)/TC4 using low-intensity pulsed ultrasound显示文摘Developing bioactive materials for bone implants to enhance bone healing and bone growth has for years been the focus of clinical research.Barium titanate(BT)is an electroactive material that can generate electrical signals in response to applied mechanical forces.In this study,a BT piezoelectric ceramic coating was synthesized on the surface of a TC4 titanium alloy,forming a BT/TC4 material,and low-intensity pulsed ultrasound(LIPUS)was then applied as a mechanical stimulus.The combined effects on the biological responses of MC3T3-E1 cells were investigated.Results of scanning electron microscopy,energy-dispersive X-ray spectroscopy,and X-ray diffraction showed that an uniform nanospheres-shaped BT coating was formed on TC4 substrate.Piezoelectric behaviors were observed using piezoelectric force microscopy with the piezoelectric coefficient d_(33)of 0.42 pC/N.Electrochemical measures indicated that LIPUS-stimulated BT/TC4 materials could produce a microcurrent of approximately 10μA/cm^(2).In vitro,the greatest osteogenesis(cell adhesion,proliferation,and osteogenic differentiation)was found in MC3T3-E1 cells when BT/TC4 was stimulated using LIPUS.Furthermore,the intracellular calcium ion concentration increased in these cells,possibly because opening of the L-type calcium ion channels was promoted and expression of the Ca_(V)1.2 protein was increased.Therefore,the piezoelectric BT/TC4 material with LIPUS loading synergistically promoted osteogenesis,rending it a potential treatment for early stage formation of reliable bone-implant contact. | Kunzhan Cai Yilai Jiao Quan Quan Yulin Hao Jie Liu Lin Wu | 2021 | Bioactive Materials2021，6，11： | 6 |
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