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Geospatial Analysis of Urban Heat Island Effects and Tree Equity
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作者 Jillian Gorrell Sharon R. Jean-Philippe +3 位作者 Paul D. Ries Jennifer K. Richards Neelam C. Poudyal Rochelle Butler 《Open Journal of Forestry》 2024年第1期1-18,共18页
In recent decades, Urban Heat Island Effects have become more pronounced and more widely examined. Despite great technological advances, our current societies still experience great spatial disparity in urban forest a... In recent decades, Urban Heat Island Effects have become more pronounced and more widely examined. Despite great technological advances, our current societies still experience great spatial disparity in urban forest access. Urban Heat Island Effects are measurable phenomenon that are being experienced by the world’s most urbanized areas, including increased summer high temperatures and lower evapotranspiration from having impervious surfaces instead of vegetation and trees. Tree canopy cover is our natural mitigation tool that absorbs sunlight for photosynthesis, protects humans from incoming radiation, and releases cooling moisture into the air. Unfortunately, urban areas typically have low levels of vegetation. Vulnerable urban communities are lower-income areas of inner cities with less access to heat protection like air conditioners. This study uses mean evapotranspiration levels to assess the variability of urban heat island effects across the state of Tennessee. Results show that increased developed land surface cover in Tennessee creates measurable changes in atmospheric evapotranspiration. As a result, the mean evapotranspiration levels in areas with less tree vegetation are significantly lower than the surrounding forested areas. Central areas of urban cities in Tennessee had lower mean evapotranspiration recordings than surrounding areas with less development. This work demonstrates the need for increased tree canopy coverage. 展开更多
关键词 Spatial Analysis Land Cover Urban Heat Island effect (UHIE) EVAPOTRANSPIRATION Tree Canopy Impervious Surface GIS Prediction Model GIS Machine Learning
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Numerical modeling of seabed morphological effects from the construction of artificial islands in Danzhou, Hainan
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作者 英晓明 贾后磊 +1 位作者 曹玲珑 谢健 《Marine Science Bulletin》 CAS 2014年第2期37-45,共9页
Haihua Islands is a large artificial island in Danzhou, Hainan. The construction of Haihua Islands changes the hYdrodynamic environment of Yangpu waters, and further affects its morphological change. Delft3D is used t... Haihua Islands is a large artificial island in Danzhou, Hainan. The construction of Haihua Islands changes the hYdrodynamic environment of Yangpu waters, and further affects its morphological change. Delft3D is used to set up a two dimensional nested hydrodynamic and sediment model for Yangpu waters in this paper, and this paper focuses on simulating the velocity and morphological change due to the construction of Haihua Islands after the verification of the model. The seabed deposition is small because of low suspended sediment concentration and less sand source near Yangpu waters. The bed level erodes in the south area of Xiaochan Reef and the Yangpu channel due to the velocity increase in the area. 展开更多
关键词 Haihua Islands seabed morphological effect numerical modeling
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基于无人机果树冠层卷吸效应的窄弧扇形防漂移喷嘴设计
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作者 李毅轩 赵耀辉 汪星星 《农机化研究》 北大核心 2025年第1期79-86,共8页
针对植保无人机对果树冠层喷洒易产生的药液漂移问题,结合植保无人机对果树喷洒时产生的卷吸效应和扇形喷嘴雾化原理,设计了一种窄弧扇形喷嘴结构,并通过对不同冠层压力损失系数下的喷洒过程进行仿真分析,得到最佳防漂移的窄弧扇形喷嘴... 针对植保无人机对果树冠层喷洒易产生的药液漂移问题,结合植保无人机对果树喷洒时产生的卷吸效应和扇形喷嘴雾化原理,设计了一种窄弧扇形喷嘴结构,并通过对不同冠层压力损失系数下的喷洒过程进行仿真分析,得到最佳防漂移的窄弧扇形喷嘴结构参数。研究结果表明:喷嘴内径增大,液膜与液带结构趋于稳定,液滴分布均匀,沉积率呈先降后升趋势;冠层压力损失系数降低,粒径频谱宽度减小,但沉积率总体提高;对较厚冠层果树植保时,选择内径1.3 mm、狭缝宽度0.15 mm的喷嘴,防漂移性能较好;对较薄冠层果树植保时,选择内径1.03 mm、狭缝宽度0.2 mm的喷嘴,防漂移性能较好;采用窄弧扇形喷嘴的液滴频谱宽度>0.7,沉积率>94.1%。 展开更多
关键词 植保无人机 窄弧扇形喷嘴 卷吸效应 防漂移性能
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Analysis on the Variation Characteristics of Temperature in Anqing City and Urban Heat Island Effect 被引量:1
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作者 刘立群 朱月霞 顾卫 《Agricultural Science & Technology》 CAS 2011年第12期1913-1916,共4页
[Objective] The aim was to analyse the variation characteristics of temperature in Anqing City and urban heat island effect.[Method] Based on the observation data of temperature from Anqing Station,other surrounding m... [Objective] The aim was to analyse the variation characteristics of temperature in Anqing City and urban heat island effect.[Method] Based on the observation data of temperature from Anqing Station,other surrounding meteorological stations and local automatic meteorological stations in suburbs,the annual variation of temperature and regional consistency was analysed,then the abrupt change of annual average temperature was tested by Mann-Kendall test,finally the influences of urban heat island effect on temperature variation in Anqing Station were studied.[Result] Affected by station migration and urban construction,the annual average temperature increased significantly in Anqing Station from 1977 to 2009,and the rising was more prominent after the middle of the 1990s.Mann-Kendall test showed that the change of temperature in Anqing Station was obviously abrupt around 1993;because of the development of urbanization,average temperature in Anqing Station was 0.8 ℃ higher than that in suburbs,and the minimum temperature rose more remarkably.In addition,urban heat island effect was the strongest in spring,followed by summer and autumn,while it was the weakest in winter.[Conclusion] The effects of urbanization development on the temperature in Anqing City were understood through this research. 展开更多
关键词 TEMPERATURE Abrupt change Urban heat island effect
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Characteristics of the Heat Island Effect in Shanghai and Its Possible Mechanism 被引量:17
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作者 陈隆勋 朱文琴 +1 位作者 周秀骥 周自江 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2003年第6期991-1001,共11页
The characteristics of the urban heat island effect and the climate change in Shanghai and its possible mechanism are analyzed based on monthly meteorological data from 1961 to 1997 at 16 stations in Shanghai and its ... The characteristics of the urban heat island effect and the climate change in Shanghai and its possible mechanism are analyzed based on monthly meteorological data from 1961 to 1997 at 16 stations in Shanghai and its adjacent areas. The results indicate that Shanghai City has the characteristics of a heat island of air temperature and maximum and minimum air temperature, a cold island of surface soil temperature, a weak rainy island of precipitation, and a turbid island of minimum visibility and aerosols, with centers at or near Longhua station (the urban station of Shanghai). Besides theses, the characteristics of a cloudy island and sunshine duration island are also obvious, but their centers are located in the southern part of the urban area and in the southern suburbs. A linear trend analysis suggests that all of the above urban effects intensified from 1961 to 1997. So far as the heat island effect is concerned, the heat island index (difference of annual temperature between Longhua and Songjiang stations) strengthens (weakens) as the economic development increases (decreases). The authors suggest that the heating increase caused by increasing energy consumption due to economic development is a main factor in controlling the climate change of Shanghai besides natural factors. On the other hand, increasing pollution aerosols contribute to the enhancement of the turbid island and cooling. On the whole, the heating effect caused by increasing energy consumption is stronger than the cooling effect caused by the turbid island and pollution aerosols. 展开更多
关键词 Shanghai heat island climate change due to economic development cooling effect due to clouds and aerosols rainy island turbid island
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Preparation and Anti-oxidative Effects of Corn Peptides 被引量:5
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作者 XU Li ZHANG Xue-zhong +2 位作者 GUO Yi REN Qiao WU Xiao-xia 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第3期299-302,共4页
Corn peptides(CP) were prepared from zein via proteolysis by means of a type of alkaline protease, Alcalase, at 50 ℃ and pH 8.0. The anti oxidative activity of the hydrolysate was examined. It was found that the... Corn peptides(CP) were prepared from zein via proteolysis by means of a type of alkaline protease, Alcalase, at 50 ℃ and pH 8.0. The anti oxidative activity of the hydrolysate was examined. It was found that the anti oxidative activity reached the maximum at the fourth hour of the hydrolysis and then decreased. The effect of the enzyme dosage on the solubility of corn protein, the dependence of hydrolysis time on the degree of the hydrolysis(DH) and molecular weight distribution were examined respectively. 30% DH was controlled on the basis of anti oxidative activity. The hydrolysate was fractionated on a Sephadex G 15 column. The anti oxidative activities were examined for all the fractions. The main fraction for anti oxidative activity was collected and characterized by the methods of amino acid analysis, the measurement of average chain length and etc .. The main M W distribution of the main fraction was 300-600 Daltons. The anti oxidative properties of the small peptides in vitro were studied. It was found that they could inhibit the auto oxidation of pyrogallol and the oxidation of hemoglobin. The hemolysis degree of erythrocyte caused by hydroxyl free radicals was decreased greatly, indicating a protective effect of the anti oxidative peptides on the cell membrane damage of erythrocyte. 展开更多
关键词 Corn Peptides PREPARATION Anti oxidative effect
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Oasis cold island effect and its influence on air temperature: a case study of Tarim Basin, Northwest China 被引量:2
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作者 HAO Xingming LI Weihong 《Journal of Arid Land》 SCIE CSCD 2016年第2期172-183,共12页
Oasis effect can improve the regional climate and habitability of an arid region. In this study, we explored the cold island effects of oases distributed along the edge of Tarim Basin by analyzing the oasis cold islan... Oasis effect can improve the regional climate and habitability of an arid region. In this study, we explored the cold island effects of oases distributed along the edge of Tarim Basin by analyzing the oasis cold island effect (OCIE) intensity, spatial-temporal variation of OCIE, factors influencing the OCIE and impacts of OCIE on air temperature using geographical statistics and GIS methods based on the MODIS land surface temperature, land use/cover change (LUCC) and observed air temperature data. Results showed that all the oases in the Tarim Basin exhibited cold island effects, with the OCIE intensity highest in summer (-9.08℃), followed by autumn (-4.24℃) and spring (-3.85℃). The total area of oasis cold island (OCI) and the comprehensive OCIE index showed the same seasonal change trend as the OCIE intensity. However, the changing trends in areas of OCI with strong, medium and weak OCIEs were inconsistent across different seasons. Farmland and water areas were found to be the key contributors that affected the OCIE, and the area and aggregation metrics of these two land use/cover types directly contributed to the OCIE. By contrast, natural vegetation, such as forest and grassland, almost had no contribution to the OCIE. Simulation of observed air temperature data showed that if farmland is replaced by forest or grassland in the oasis, the mean, maximum and minimum air temperatures will increase significantly. This heating effect will be higher in summer (reaching 1.14℃ to 2.08℃) and lower in spring and autumn. Moreover, the heating effect of farmland being replaced by forest will be higher than that of farmland being replaced by grassland. These results can provide a basis for understanding the cold island effect of oases in arid regions. 展开更多
关键词 oasis cold island effect comprehensive oasis cold island effect index landscape index oasis evolution arid environment
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Characteristics of urban heat island effect in Lhasa City 被引量:2
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作者 Zhuo Ga YunDan NiMa +1 位作者 Jian Jun PuBu CiRen 《Research in Cold and Arid Regions》 2011年第1期70-77,共8页
This paper analyzes the Urban Heat Island (UHI) effect in Lhasa City of Tibet using meteorological observations, the Normalized Difference Vegetation Index (NDVI), Land Surface Temperature (LST) data obtained fr... This paper analyzes the Urban Heat Island (UHI) effect in Lhasa City of Tibet using meteorological observations, the Normalized Difference Vegetation Index (NDVI), Land Surface Temperature (LST) data obtained from Earth Observing System/Moderate resolution Imaging Spectroradiometer (EOS/MODIS) information, and correlation and composite analyses. The results show: (1) Areas with high temperature are primarily located in the center of the city or nearby counties, while low temperature areas are in the suburbs of counties. The area with high temperature has expanded in recent years and some high-temperature centers have even migrated to certain other regions. (2) The UHI intensity tends to be stronger both in annual and seasonal variations, especially in winter. Also, LST is somewhat positively related to mean air temperature. (3) A negative correlation exists between the changes of LST and NDVI with the increase of vegetation from urban to rural areas in different seasons. (4) The UHI intensity is negatively correlated with precipitation while positively correlated with wind speed, and the relation between the UHI intensity and evaporation varies with the seasons, namely, the intensity is positively correlated with summer evaporation but negatively corre- lated with winter evaporation. (5) UHI intensity might be enhanced by intensified urbanization, wherein built-up areas expand, there is increased heat from human activity, and there is more artificial heat input to the atmosphere. 展开更多
关键词 LHASA urban heat island effect CHARACTERISTICS meteorological conditions
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The Environmental Effects of Tourism Architecture on Island Ecosystem in Cayo Guillermo, Cuba 被引量:2
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作者 Lourdes Ruiz Gutiérrez 《Journal of Environmental Protection》 2015年第9期1057-1065,共9页
The objective of this study is to determine the main adverse impacts that may be caused by tourism architecture upon island ecosystems consisting of small islands or islets and to propose an architectural and landscap... The objective of this study is to determine the main adverse impacts that may be caused by tourism architecture upon island ecosystems consisting of small islands or islets and to propose an architectural and landscape design with a focus on the environmental sustainability of the same. A study of projects was undertaken in Cayo Guillermo, located to the north of Ciego de Avila in Cuba using methods of life-cycle assessment of buildings, matrix methods of the activities that caused severe environmental impact and statistical processing through multivariate analysis. Conclusions were reached on the need for designs that did not harm the ecosystems of islands with high ecological fragility. It has been determined that suitable construction intervention would decrease the negative impact and would allow the natural resources of these valuable ecosystems that are the basis for responsible sun and sand tourism to be preserved. 展开更多
关键词 ENVIRONMENTAL effects ARCHITECTURE TOURISM ISLAND ECOSYSTEM
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Change in Urban Wetlands and Their Cold Island Effects in Response to Rapid Urbanization 被引量:6
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作者 ZHANG Wei JIANG Jingang ZHU Yubi 《Chinese Geographical Science》 SCIE CSCD 2015年第4期462-471,共10页
The cold-island effect of urban wetlands has received increasing attention in recent years due to its important role in the alleviation of urban heat islands.Hangzhou,a representative rapidly urbanizing city with rich... The cold-island effect of urban wetlands has received increasing attention in recent years due to its important role in the alleviation of urban heat islands.Hangzhou,a representative rapidly urbanizing city with rich wetlands in China,was selected as a case study for researching the changes that the urban wetlands have undergone and their impact on the urban thermal environment.Land surface temperature(LST) was acquired from the thermal infrared data of Landsat 5 Thematic Mapper(TM) images in 1990,1995,2000,2006,and 2010,using the single-channel method.The results are as follows:1) considering the changes in land use,the urban wetlands located to the west of Hangzhou have decreased significantly during 1990–2010 because of rapid urbanization.In the Xixi Wetland,the change in land use was relatively small and most of the water body and vegetation were preserved.However,to the east of the Xixi Wetland,large areas of water body and vegetation have been replaced by built-up land as a result of the urbanization process;2) considering the change in LST,it was found from land surface temperature retrieval that the changing spatial pattern of the thermal field was highly correlated with land use changes.Low temperature regions of the eastern Xixi Wetland were gradually eroded by high temperature regions,and the centroid of the heat island in East Xixi was found to be constantly shifting westward.In addition,the difference in LST between the Xixi Wetland and East Xixi has increased;3) considering the impact factors for this area,land use structure and patch shape were found to have a significant impact on LST,shown by the results of multiple linear stepwise regressions.Increasing the size of the wetlands in urban planning is considered to be the most effective measure in alleviating the urban heat island effect.Moreover,reducing the spatial complexity of landscape patches also contributes to the alleviation of the urban heat island effect. 展开更多
关键词 rapid urbanization cold island effect heat island effect Thematic Mapper(TM) Xixi Wetland Hangzhou
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Spatial and temporal analysis of urban heat island effect over Tiruchirappalli city using geospatial techniques 被引量:2
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作者 Ajay Badugu K.S.Arunab +1 位作者 Aneesh Mathew P.Sarwesh 《Geodesy and Geodynamics》 EI CSCD 2023年第3期275-291,共17页
Alterations made to the natural ground surface and the anthropogenic activity elevate the surface and air temperature in the urban areas compared with the surrounding rural areas,known as urban heat island effect.Ther... Alterations made to the natural ground surface and the anthropogenic activity elevate the surface and air temperature in the urban areas compared with the surrounding rural areas,known as urban heat island effect.Thermal remote sensors measure the radiation emitted by ground objects,which can be used to estimate the land surface temperature and are beneficial for studying urban heat island effects.The present study investigates the spatial and temporal variations in the effects of urban heat island over Tiruchirappalli city in India during the summer and winter seasons.The study also identifies hot spots and cold spots within the study area.In this study,a significant land surface temperature difference was observed between the urban and rural areas,predominantly at night,indicating the presence of urban heat island at night.These diurnal land surface temperature fluctuations are also detected seasonally,with a relatively higher temperature intensity during the summer.The trend line analysis shows that the mean land surface temperature of the study area is increasing at a rate of 0.166 K/decade with p less than 0.01.By using the spatial autocorrelation method with the urban heat island index as the key parameter,hot spots with a 99 percent confidence level and a 95 percent confidence level were found within the urban area.A hot spot with 95 and 90 percent confidence level was identified outside the urban area.This spike in temperature for a particular region in the rural area is due to industry and the associated built-up area.The study also identified cold spots with a 90 percent confidence level within the rural area.However,cold spots with a 95 and 99 percent confidence level were not identified within the study area. 展开更多
关键词 URBANIZATION Land surface temperature Urban heat island effect Hot spots Remote sensing
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Impact of the Urban Heat Island Effect on Ozone Pollution in Chengdu City,China 被引量:1
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作者 SHI Haoyuan SONG Xingtao ZENG Shenglan 《Chinese Geographical Science》 SCIE CSCD 2023年第6期1017-1032,共16页
With the advancement of urbanization,the urban heat island effect and ozone pollution have become hot issues in urban research.The urban heat island effect can impact ozone conversion,but its mechanism of action is un... With the advancement of urbanization,the urban heat island effect and ozone pollution have become hot issues in urban research.The urban heat island effect can impact ozone conversion,but its mechanism of action is unclear.In this study,the effects of the urban heat island effect on ozone concentration in Chengdu City,China,were investigated by comparing the ozone concentration under different heat island levels with ozone data from March 2020 to February 2021 and the temperature and wind field data of ERA5-Land during the same period.The results showed that:1)regarding the distribution characteristics,the ozone concentration in Chengdu presented a‘high in summer and low in winter’distribution.The ozone concentration in summer(189.54µg/m^(3))was nearly twice that in winter(91.99µg/m^(3)),and the ozone diurnal variation presented a‘single peak and single valley’distribution,with a peak at 16:00.2)For the characteristics of the heat island effect,the heat island intensity in Chengdu was obviously higher in spring than in other seasons,and the diurnal variation showed a‘single peak and single valley’distribution,with the peak and trough values appearing at 9:00 and 17:00,respectively.Spatially,the eastern part of Chengdu was a heat island,while the western and northwestern parts were mostly cold island.3)The correlation analysis between heat island intensity and ozone concentration showed a significant positive correlation but with a 7–8 h time lag.Ambient air temperature was not the main factor affecting ozone concentration.The heat island effect impacts the ozone concentration in two ways:changing the local heat budget to promote ozone generation and forming local urban wind,which promotes ozone diffusion or accumulation and forms different areas of low and high ozone values. 展开更多
关键词 ozone pollution urban heat island effect heat island intensity lag correlation Chengdu China
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The Effects of Road and Other Pavement Materials on Urban Heat Island (A Case Study of Port Harcourt City) 被引量:1
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作者 Elenwo Ephraim Ikechukwu 《Journal of Environmental Protection》 2015年第4期328-340,共13页
Urban centers are consistently exhibiting higher temperature than its surrounding suburban rural areas. The large amount of heat generated from urban structures such as road materials and pavement materials and other ... Urban centers are consistently exhibiting higher temperature than its surrounding suburban rural areas. The large amount of heat generated from urban structures such as road materials and pavement materials and other anthropogenic heat sources are the main causes of Urban Heat Island (UHI). The sources of data for this research included primary and secondary sources. Other techniques employed for data collection were direct measurement and readings on the road and pavement materials. The research found out that, there was consistency in rising temperature at different time of the day by the different road and pavement materials. Asphalt has the greatest effect of increasing the urban temperature four degrees higher, followed by concrete, three degree rise in temperature, and earth (ordinary ground) by two degree rise and vegetation (grass) by one degree rise in temperature. The overall effect on the residents of the study area ranges from increase in hotness of the day;44.6% respondents agrees;while 34.3% says it affects the ambient air quality of the area, and other effects such as increased ground level ozone, suffocation, sleeplessness and restlessness as a result of excessive high temperature especially at night are identified in this paper. The research recommends the review or redesigning of the entire Port Harcourt city Master Plan to make provision for creation of more green areas rather than pavements and concreted areas to reduce the effects of (UHI) and ultimately improve the comfort and living conditions of the people in a the garden city Port Harcourt. 展开更多
关键词 effectS Road and PAVEMENT Materials Urban Heat ISLAND RESIDENTS PORT Harcourt
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Cloning,Eukaryotic Expression of Human ISG20 and Preliminary Study on the Effect of Its Anti-HBV 被引量:3
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作者 郝友华 杨东亮 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2008年第1期11-13,共3页
Human ISG20 gene was cloned and the effect of its anti-HBV was primarily studied. The ISG20 gene was amplified from HeLa cells by RT-PCR and recombinant vector expressing ISG20 was constructed by genetic engineering. ... Human ISG20 gene was cloned and the effect of its anti-HBV was primarily studied. The ISG20 gene was amplified from HeLa cells by RT-PCR and recombinant vector expressing ISG20 was constructed by genetic engineering. The overexpression of ISG20 in HepG2 cells was detected by Western blot and the levels of secretion of HBs antigen and HBe antigen tested by ELISA. The results showed that: (1) Sequence of ISG20 cloned was consistent to that published in Genebank; (2) Recombinant vector expressing ISG20 could be expressed in HepG2 cells by transfection; (3) The overexpression of ISG20 protein could reduce the levels of the secretion of HBs antigen and HBe antigen in transfected HepG2 cells. It was suggested that the overexpression of recombinant ISG20 in culture cells could reduce the synthesis of HBV proteins. 展开更多
关键词 human ISG20 effect of anti-HBV
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Heavy-ion and pulsed-laser single event effects in 130-nm CMOS-based thin/thick gate oxide anti-fuse PROMs 被引量:8
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作者 Chang Cai Tian-Qi Liu +8 位作者 Xiao-Yuan Li Jie Liu Zhan-Gang Zhang Chao Geng Pei-Xiong Zhao Dong-Qing Li Bing Ye Qing-Gang Ji Li-Hua Mo 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第5期92-102,共11页
Single event effects of 1-T structure programmable read-only memory(PROM) devices fabricated with a 130-nm complementary metal oxide semiconductorbased thin/thick gate oxide anti-fuse process were investigated using h... Single event effects of 1-T structure programmable read-only memory(PROM) devices fabricated with a 130-nm complementary metal oxide semiconductorbased thin/thick gate oxide anti-fuse process were investigated using heavy ions and a picosecond pulsed laser. The cross sections of a single event upset(SEU) for radiationhardened PROMs were measured using a linear energy transfer(LET) ranging from 9.2 to 95.6 MeV cm^2mg^(-1).The result indicated that the LET threshold for a dynamic bit upset was ~ 9 MeV cm^2mg^(-1), which was lower than the threshold of ~ 20 MeV cm^2mg^(-1) for an address counter upset owing to the additional triple modular redundancy structure present in the latch. In addition, a slight hard error was observed in the anti-fuse structure when employing209 Bi ions with extremely high LET values(~ 91.6 MeV cm^2mg^(-1)) and large ion fluence(~ 1×10~8 ions cm^(-2)). To identify the detailed sensitive position of a SEU in PROMs, a pulsed laser with a 5-μm beam spot was used to scan the entire surface of the device.This revealed that the upset occurred in the peripheral circuits of the internal power source and I/O pairs rather than in the internal latches and buffers. This was subsequently confirmed by a ^(181)Ta experiment. Based on the experimental data and a rectangular parallelepiped model of the sensitive volume, the space error rates for the used PROMs were calculated using the CRèME-96 prediction tool. The results showed that this type of PROM was suitable for specific space applications, even in the geosynchronous orbit. 展开更多
关键词 Anti-fuse PROM Single event effects HEAVY IONS Pulsed laser Space error rate
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Tidal Effects on the Bottom Thermal Front of North Yellow Sea Cold Water Mass near Zhangzi Island in Summer 2009
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作者 XIA Yingying BAO Xianwen +3 位作者 SONG Dehai DING Yang WAN Kai YAN Yuhan 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第4期751-760,共10页
Three seabed-mounted TD/CTD chains and two upward-looking acoustic Doppler current profilers (ADCPs) in the southwest of Zhangzi Island are used and a simultaneous cruise observation in the northern North Yellow Sea (... Three seabed-mounted TD/CTD chains and two upward-looking acoustic Doppler current profilers (ADCPs) in the southwest of Zhangzi Island are used and a simultaneous cruise observation in the northern North Yellow Sea (NYS) is conducted to study temperature variation in the bottom thermal front zone of the NYS Cold Water Mass (NYSCWM) during the summer of 2009. In the flood-ebb tidal cycles, the bottom temperature decreases (increases) during flood (ebb) tides, which are dominated by the tidal-current induced horizontal advection. The ebb tide-induced temperature increase is larger than the flood tide-induced tempera- ture decrease due to seasonal warming. In the spring-neap tidal cycles, the temperature and the vertical temperature structure show notable fortnightly variation from 16 July to 25 August. The bottom temperature increases from neap to spring tides and decreases from spring to neap. The Richardson number demonstrates strengthened vertical mixing during spring tides but enhanced stratifica- tion during neap tides. The spring-neap variation in vertical shear caused by tidal current is the dominant factor that induces the fort- nightly variation in vertical mixing and thus bottom temperature. 展开更多
关键词 TIDAL effect NORTH YELLOW Sea Cold Water Mass temperature variation Zhangzi ISLAND thermal front
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Effects of Climate and the Urban Heat Island Effect on Urban Tree Growth in Houston 被引量:2
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作者 Astrid Moser Enno Uhl +4 位作者 Thomas Rotzer Peter Biber Jens Dahlhausen Barry Lefer Hans Pretzsch 《Open Journal of Forestry》 2017年第4期428-445,共18页
The growing conditions of urban trees differ substantially from forest sites and are mainly characterized by small planting pits with less water, nutrient and aeration availability, high temperatures and radiation inp... The growing conditions of urban trees differ substantially from forest sites and are mainly characterized by small planting pits with less water, nutrient and aeration availability, high temperatures and radiation inputs as well as pollution and soil compaction. Especially, global warming can amplify the negative effects of urban microclimates on tree growth, health and well-being of citizens. To quantify the growth of urban trees influenced by the urban climate, ten urban tree species in four climate zones were assessed in an overarching worldwide dendrochronological study. The focus of this analysis was the species water oak (Quercus nigra L.) in Houston, Texas, USA. Similar to the overall growth trend, we found in urban trees, water oaks displayed an accelerated growth during the last decades. Moreover, water oaks in the city center grew better than the water oaks growing in the rural surroundings of Houston, though this trend was reversed with high age. Growth habitat (urban, suburban, rural and forest) significantly affected tree growth (p < 0.001) with urban trees growing faster than rural growing trees and forest trees, though a younger age of urban trees might influence the found growth patterns. Growing site in terms of cardinal direction did not markedly influence tree growth, which was more influenced by the prevalent climatic conditions of Houston and the urban climate. Higher temperatures, an extended growing season and eutrophication can cause an accelerated growth of trees in urban regions across, across all climatic zones. However, an accelerated growth rate can have negative consequences like quicker ageing and tree death resulting in higher costs for new plantings and tree management as well as the decrease in ecosystem services due to a lack of old trees providing greatest benefits for mitigating the negative effects of the urban climate. 展开更多
关键词 Climate Change Growth Trends Heat Island effect Quercus nigra Tree Ring Analyses
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A new cerebroside and its anti-proliferation effect on VSMCs from the radix of Cyperus rotundus L. 被引量:5
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作者 Pei Liu Li Liu +2 位作者 Yu Ping Tang Jin Ao Duan Nian Yun Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第5期606-609,共4页
A new cerebroside,1-O-(β-D-glucopyranosyloxy)-(2S,3R,4E,8Z)-2-[(2′R)-2’-hydroxylignoceranoylamino]-4,8-tetradecene-3- diol was isolated from the 60%EtOH extract of traditional Chinese medical plant Cyperus rotundus... A new cerebroside,1-O-(β-D-glucopyranosyloxy)-(2S,3R,4E,8Z)-2-[(2′R)-2’-hydroxylignoceranoylamino]-4,8-tetradecene-3- diol was isolated from the 60%EtOH extract of traditional Chinese medical plant Cyperus rotundus L.Its structure was determined on the basis of spectroscopic data.This new compound showed anti-proliferation effect on vascular smooth muscle cells(VSMCs). 展开更多
关键词 Cyperus rotundus CEREBROSIDE Anti-proliferation effect Vascular smooth muscle cells(VSMCs)
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Development and evaluation of a herbal formulation with antipathogenic activities and probiotics stimulatory effects 被引量:4
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作者 ZHOU Qian WANG Si-si +2 位作者 YANG Guang ZHAO Wen LI Hui-ling 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第5期1103-1111,共9页
Searching alternative feed antibiotics is always a study hotspot in the field of animal production. In this study, the antipathogenic activities and probiotics stimulatory effects of 30 kinds of herbs were screened th... Searching alternative feed antibiotics is always a study hotspot in the field of animal production. In this study, the antipathogenic activities and probiotics stimulatory effects of 30 kinds of herbs were screened through Oxford cup method and Hungate roll method. 15 herbs showed significantly antibacterial activities(P〈0.05) against Escherichia coli, Salmonella enteritidis, Salmonella typhimurium and Staphylococcus aureus. Seven herbs showed greatly stimulatory promoting effects on Lactobacillus acidophilus and Bifidobacterium longum. Finally, five herbs were combined for the developed formulation with selective antibacterial properties and they were Mume Fructus(35%), Isatidis Folium(25%), Moslae Herba(20%), Chrysanthemi Indici Flos(13%) and Bupleuri Radix(7%). The herbal formulation showed significantly antibacterial abilities against four pathogens and stimulatory promoting abilities on two probiotics in vitro and the equivalent activities in broiler chickens in vivo against E. coli and L. acidophilus. The toxicity study showed it had no toxicity, which indicated that it would be a kind of preferred candidate for an alternative antibiotic in future animal production. 展开更多
关键词 herbal formulation alternative feed antibiotic anti-pathogenic activity probiotic stimulatory effect
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Changes of Urban Boundary Layer Thermodynamic Stability Induced by Heat Island Effect and Their Influences on Precipitation 被引量:1
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作者 WANG Jian-peng1,SUN Ji-song2,WANG Shi-gong3,ZHANG Hong1,QU Jing1,MENG Xiao-rong1,JING Li-na1 Xi’an Meteorological Bureau,Xi’an 710016,China 《Meteorological and Environmental Research》 CAS 2011年第10期39-43,49,共6页
[Objective] The aim was to study the characteristics of the changes of the urban boundary layer thermodynamic stability induced by heat island effect and their influences on precipitation.[Method] Proceeding from the ... [Objective] The aim was to study the characteristics of the changes of the urban boundary layer thermodynamic stability induced by heat island effect and their influences on precipitation.[Method] Proceeding from the thermodynamic equation,the changes of urban boundary layer thermodynamic stability caused by the urban heat disturbance and the mean state of heat island effect were discussed.The influence of the changes of urban boundary layer thermodynamic stability on the precipitation was expounded.Combining with case study of precipitation in Xi’an,the test was verified.[Result] Under interaction between the disturbed temperature and disturbed airflow,the boundary thermal disturbed stability(θ’z) was positive in the urban zone,as well as in the upstream and downstream areas of the city.But the stability in the urban zone was weaker than the suburbs,which favored for the short-time convective precipitation.For the boundary layer mean thermal stability(θ-0-0z) under the interaction between the mean airflow and mean environmental temperature,if the city zone was in the front of the warm ridge,the stability in the upstream of the city weakened which increased the instability of the boundary layer,while it increased in the downstream of the city.It was contrary if the city zone was in the font of the cold trough.For the mean airflow(prevailing wind) and the mean horizontal disturbed temperature,if it was upward motion in the boundary layer,the boundary layer mean thermal disturbed stability(θ’-0z) was negative in the downstream and positive in the upstream.Strong precipitation occured in the upstream of the city.It was contrary if it was descending air in the boundary layer.[Conclusion] The above results served some references for the fine city forecast. 展开更多
关键词 Heat-island effect Boundary layer STABILITY PRECIPITATION China
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