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Sensitivity of Atlantic Meridional Overturning Circulation to the Dynamical Framework in an Ocean General Circulation Model

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Journal of Meteorological Research 2017年第3期31卷 490-501页

作者： xiaolan li Yongqiang YU Hailong liU Pengfei liN State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences

The horizontal coordinate systems commonly used in most global ocean models are the spherical latitude-longit- ude grid and displaced poles, such as a tripolar grid. The effect of the horizontal coordinate system on Atlantic meri- dional overturning circulation （AMOC） is evaluated by using an OGCM （ocean general circulation model）. Two ex- periments are conducted with the model---one using a latitude-longitude grid （referred to as Latl） and the other us- ing a tripolar grid （referred to as Tri）. The results show that Tri simulates a stronger North Atlantic deep water （NADW） than Lat_l, as more saline water masses enter the Greenland-Iceland-Norwegian （GIN） seas in Tri. The stronger NADW can be attributed to two factors. One is the removal of the zonal filter in Tri, which leads to an in- creasing of the zonal gradient of temperature and salinity, thus strengthening the north geostrophic flow. In turn, it decreases the positive subsurface temperature and salinity biases in the subtropical regions. The other may be associ- ated with topography at the North Pole, because realistic topography is applied in the tripolar grid while the latitude-longitude grid employs an artificial island around the North Pole. In order to evaluate the effect of the filter on AMOC, three enhanced filter experiments are carried out. Compared to Lat_l, an enhanced filter can also aug- ment NADW formation, since more saline water is suppressed in the GIN seas, but accumulated in the Labrador Sea, especially in experiment Lat_2 S, which is the experiment with an enhanced filter on salinity.

关键词： AMOC OGCM tripolar grid latitude-longitude grid zonal filter

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Spatial heterogeneity of plant species on the windward slope of active sand dunes in a semi-arid region of China

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Journal of Arid Land 2013年第1期5卷 80-88页

作者： DeMing JIANG ChunPing MIAO XueHua li xiaolan li ALAMUSA QuanLai ZHOU Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Xinjiang Academy of Agricultural and Reclamation Sciences Shihezi 832000 China

Species richness and abundance are two important species diversity variables that have attracted particular attention because of their significance in determining present and future species composition conditions. This paper aims to explain the qualitative and quantitative relationships between species diversity pattern and grain size （i.e. size of the sampling unit）, and species diversity pattern and sampling area, and to analyze species diversity variability on active sand dunes in the Horqin Sandy Land, northeastern Inner Mongolia, China. A 50 mx50 m sampling plot was selected on the windward slope, where the dominant species was annual herb Agriophyllum squarrosum. Species composition and abundance at five grain sizes were recorded, and the species-area curves were produced for thirteen grain sizes. The range of values for species abundance tended to increase with in- creasing grain size in the study area, whereas, generally, species richness did not follow this rule because of poor species richness on the windward slope of active sand dunes. However, the homogeneity of species richness in- creased significantly. With the increase in sampling area, species abundance increased linearly, but richness in- creased logarithmically. Furthermore, variograms showed that species diversity on the windward slope of active sand dunes was weakly anisotropic and the distribution pattern was random, according to the Moran Coefficient. The results also showed that species richness was low, with a random distribution pattern. This conflicts with the results of previous studies that showed spatial aggregation in lower richness in a sampling area within a community and inferred that the physical processes play a more important role in species diversity than distribution pattern on active sand dunes. Further research into different diversity patterns and mechanisms between active sand dunes and interdune lowlands should be conducted to better understand biodiversity conservation in

关键词： abundance richness grain size species-area curve variogram Horqin Sandy Land

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Comparison of Sunshine Duration Measurements between a Jordan Sunshine Recorder and Three Automatic Sensors at Shangdianzi GAW Station

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Journal of Meteorological Research 2021年第4期35卷 716-728页

作者： Huaigang ZHOU Weijun QUAN Zhenfa WANG xiaolan li Yingruo li Hujia ZHAO Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089 Environmental Meteorology Forecast Center of Beijing-Tianjin-Hebei Beijing 100089 Institute of Atmospheric Environment China Meteorological AdministrationShenyang 110016

We used parallel sunshine duration datasets obtained with a Jordan sunshine recorder and three automatic sunshine duration sensors to investigate the differences between these *** used measurements obtained at Shangdianzi(SDZ)regional Global Atmosphere Watch(GAW)station with a Jordan sunshine recorder,a DFC2 photoelectric sunshine meter,a CHP1 pyrheliometer,and two CMP11 pyranometers from 1 January to 5 July 2019 and from 3 November 2020 to 28 February *** results showed that the daily sunshine duration measurements obtained from the Jordan sunshine recorder were comparable with those from the DFC2 meter and the CMP11 pyranometers under all-sky conditions,but were considerably different from those observed by the CHP1 *** analysis of potential influencing factors showed that the solar zenith angle,the spectral range of the automatic sensors,the relative humidity,and the sky conditions were the main factors affecting the measurements of sunshine duration between the Jordan sunshine recorder and three automatic *** proposed a simple linear regression function-the DFC2-equivalent sunshine duration estimation(DFCESD)model—to guarantee the consistency of the long-term sunshine duration series observed by the Jordan sunshine recorder at SDZ and the measurements from the DFC2 *** of the DFCESD model showed that the mean absolute difference(MAD)between the daily sunshine duration observed by the Jordan sunshine recorder and those from the DFC2 meter improved from-0.7 to-0.2 h day^(-1),the relative deviation(RD)improved from-9.3%to-2.3%,and the root-mean-square deviation(RMSD)decreased from 1.0 to 0.8 h day^(-1).

关键词： sunshine duration Jordan sunshine recorder pyrheliometer pyranometer Shangdianzi station

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Migration characteristics of neural stem cells for glioma cells in vivo and in vitro

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Neural Regeneration Research 2011年第1期6卷 12-17页

作者： Jianxiong liu Yi Zhang Haixia liu li Qiao xiaolan Xie Department of Neurosurgery Gansu Provincial People's Hospital Lanzhou 730000 Gansu Province China

This study analyzed migration characteristics of neural stem cells （NSCs） in vitro and in vivo, as well as exogenous gene expression in the brain following transfection of NSCs with an enhanced green fluorescent protein （EGFP） gene expression vector plRES2-EGFP plasmid, in glioma experimental models. NSCs slowly migrated towards glioma cells （C6 cells） in culture, although mouse embryonic fibroblasts 3T3 cells did not migrate. NSCs rapidly migrated to the tumor bed, and to tissues surrounding the tumor and metastatic lesions. A large number of EGFP-expressing cells formed distinct colonies in and surrounding the tumor following NSCs-EGFP transfection. EGFP-positive cells aggregated in incubation sites following 3T3-EGFP treatment. Results suggested that NSCs could be used to track tumor cells in vitro. In vivo, transplanted NSCs survived expressed transfected exogenous genes, migrated to the tumor bed, and expressed exogenous genes.

关键词： glioma stem cells gene transfection tracing migration

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Effect of baclofen combined with neural facilitation technique on the reduction of muscular spasm in patients with spinal cord injury

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Neural Regeneration Research 2007年第8期2卷 510-512页

作者： Shun li Senxin Xue Zhixiang li xiaolan liu Department of Rehabilitation the Third Affiliated Hospital Guangzhou Medical College Guangzhou 510150 Guangdong Province China

BACKGROUND： Recent researches have demonstrated that baclofen is a commonly central anti-spasm drug. In addition, neural facilitation technique based on nerve development and neurophysiology is widely used for rehabilitation training of motor disorder after central nerve injury. However, whether baclofen combining with neural facilitation technique can relieve muscular spasm after spinal cord injury needs further studies. OBJECTIVE： To observe the effect of baclofen combining with neural facilitation technique on decreasing muscular tension in two lower extremities after spinal cord injury. DESIGN： Randomized controlled study. SETTING- Departments of Rehabilitation and Orthopaedics, the Third Affiliated Hospital of Guangzhou Medical College. PARTICIPANTS： A total of 28 patients with spinal cord injury, including 17 males and 11 females, whose age ranged from 31 to 71 years, were selected from Departments of Rehabilitation and Orthopaedics, the Third Affiliated Hospital of Guangzhou Medical College from March 2005 to September 2006. The illness course ranged from 22 to 54 days and the mean course was （38±8） days. All patients were diagnosed as the fLrst onset and the increase of extensor muscular tension in two lower extremities after thoracic vertebra injury by using spine MR or CT examination. Informed consents were obtained from all the patients. METHODS： All 28 patients who had upper motor neuronal paralysis in two lower extremities after spinal cord injury in thoracic vertebra region were randomly divided into treatment group and control group with 14 cases in each group. Patients in both groups received routine therapy, while those in the treatment group were treated with oral baclofen （the beginning dosage： 5 rag/time; three times per day, 5 mg was increased every three days; the maximal dosage was 60 mg/day; 6 weeks in total）（made in Weicai Pharmaceutical Co., Ltd.; tablet; batch number： HC20040029） combining with neural facilitation technique, which accorde

关键词： baclofen spinal cord injury spasm

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Multilevel air quality evolution in Shenyang:Impact of elevated point emission reduction

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Journal of Environmental Sciences 2022年第3期34卷 300-310页

作者： xiaolan li Guiqian Tang liguang li Weijun Quan Yangfeng Wang Ziqi Zhao Ningwei liu Ye Hong Yanjun Ma Institute of Atmospheric Environment China Meteorological AdministrationNo.388 Changbai South RoadShenyangLiaoning 110166China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Environmental Meteorology Forecast Center of Beijing-Tianjin-Hebei Beijing 100089China

Visibility observed at different altitudes is favorable to understand the causes of air *** conducted 4-years of observations of visibility at 2.8 and 60 m and particulate matter(PM)concentrations from 2015 to 2018 in Shenyang,a provincial city in Northeast *** results indicated that visibility increased with the increasing height in winter(especially at night),and decreased with height in summer(especially at the daytime).PM concentration exhibited opposite vertical variation to visibility,reflecting that visibility de-grades with the increase of aerosol concentration in the *** radiosonde meteorological data showed that weak turbulence in the planetary boundary layer(PBL)in winter favored aerosols'accumulation near the *** in summer,unstable atmospheric con-ditions,upper-level moister environment,and regional transport of air pollutants resulted in the deterioration of upper-level ***-annual variation in the two-level visibility indicated that the upper-level visibility improved more significantly than low-level visibil-ity,much likely due to the reduction in emission of elevated point sources in *** study suggested that strengthening the control of surface non-point emissions is a promis-ing control strategy to improve Shenyang air quality.

关键词： Aerosol pollution Atmospheric visibility Planetary boundary layer Northeast China Vertical evolution

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Spatiotemporal Variations and Regional Transport of Air Pollutants in Two Urban Agglomerations in Northeast China Plain

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Chinese Geographical Science 2019年第6期29卷 917-933页

作者： li xiaolan HU Xiaoming SHI Shuaiyi SHEN lidu LUAN Lan MA Yanjun Institute of Atmospheric Environment China Meteorological AdministrationShenyang 110166China Center for Analysis and Prediction of Storms University of OklahomaNormanOK 73072USA School of Meteorology University of OklahomaNormanOK 73072USA State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Shenyang Regional Climatic Center Shenyang 110166China Chinese Academy of Meteorological Sciences Beijing 100081China

Characteristics of air pollution in Northeast China(NEC) received less research attention in the past comparing to other heavily polluted regions in *** variations of six criteria air pollutants(PM10, PM2.5, SO2, NO2, O3 and CO) in Central liaoning Urban Agglomeration(CLUA) and Harbin-Changchun Urban Agglomeration(HCUA) in NEC Plain were analyzed in this study based on three-year hourly observations of air pollutants and meteorological variables from 2015 to *** results indicated that the annual mean concentrations of air pollutants are generally higher in the middle and southern regions in NEC Plain and lower in the northern *** such as Shenyang, Harbin and Changchun experience severe air pollution, with a three-year averaged air quality index(AQI) larger than 80, far exceeding the daily AQI standard at the first-level of 50 in *** annual mean PM and SO2 concentrations decrease most significantly in NEC urban agglomerations from 2015 to 2017, followed by CO and NO2, while O3 shows a slight increasing *** the six pollutants exhibit obvious seasonal and diurnal variations, and these variations are dictated by local emission and meteorological ***2.5 and O3 concentrations in NEC urban agglomerations strongly depend on wind *** O3 concentrations at different cities usually occur in presence of strong winds but are independent on wind direction(WD), while high PM2.5 is usually accompanied by weak winds and poor dispersion condition, and sometimes also occur when the northerly or southerly winds are *** transport of air pollutants between NEC urban agglomerations is common.A severe haze event on November 1–4, 2017 is examined to demonstrate the role of regional transport on pollution.

关键词： criteria air pollutant meteorological condition regional transport urban agglomeration of Northeast China

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Annual plants in arid and semi-arid desert regions

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Frontiers in Biology 2008年第3期3卷 259-264页

作者： Xuehua li xiaolan li Deming JIANG Zhimin liU Qinghe YU Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China Graduate University of Chinese Academy of Sciences Beijing 100039China Environmental Protection Bureau of Chaoyang County Chaoyang 122000China

Annual plants are the main vegetation in arid and semi-arid desert *** of their unique traits,they are the optimal experimental subjects for eco-logical *** this article,we summarize annual plants’seed germination strategies,seedling adaptability mechanism to environments,seed dispersal,and soil seed *** also discuss the biotic and abiotic factors affecting the composition and dynamics of annual plant populations and *** annual plants have important ecological functions in desert vegetation systems,this study on annual plants will be of great benefit to the conservation and restoration of desert ecosystems,the rational utilization of resources,and the sustainable development of desert regions.

关键词： desert region annual plants seed germination seedling seed bank population dynamics

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Characteristics of Boundary Layer Structure during a Persistent Haze Event in the Central liaoning City Cluster, Northeast China

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Journal of Meteorological Research 2018年第2期32卷 302-312页

作者： xiaolan li Yangfeng WANG lidu SHEN Hongsheng ZHANG Hujia ZHAO Yunhai ZHANG Yanjun MA Institute of Atmospheric Environment China Meteorological Administration Shenyang 110166 Shenyang Regional Climatic Center Shenyang 110166 Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of Physics Peking University Beijing 100871

The characteristics of boundary layer structure during a persistent regional haze event over the central liaoning city cluster of Northeast China from 16 to 21 December 2016 were investigated based on the measurements of particulate matter（PM） concentration and the meteorological data within the atmospheric boundary layer（ABL）. During the observational period, the maximum hourly mean PM_（2.5） and PM10 concentrations in Shenyang, Anshan, Fushun, and Benxi ranged from 276 to 355 μg m–3 and from 378 to 442 μg m–3, respectively, and the lowest hourly mean atmospheric visibility（VIS） in different cities ranged from 0.14 to 0.64 km. The central liaoning city cluster was located in the front of a slowly moving high pressure and was mainly controlled by southerly winds. Wind speed（WS） within the ABL（〈 2 km） decreased significantly and WS at 10-m height mostly remained below 2 m s–1 during the hazy episodes, which was favorable for the accumulation of air pollutants. A potential temperature inversion layer existed throughout the entire ABL during the earlier hazy episode [from 0500 Local Time（LT） 18 December to 1100 LT 19 December], and then a potential temperature inversion layer developed with the bottom gradually decreased from 900 m to 300 m. Such a stable atmospheric stratification further weakened pollutant dispersion. The atmospheric boundary layer height（ABLH） estimated based on potential temperature profiles was mostly lower than 400 m and varied oppositely with PM_（2.5） in Shenyang. In summary, weak winds due to calm synoptic conditions, strong thermal inversion layer, and shallow atmospheric boundary layer contributed to the formation and development of this haze *** backward trajectory analysis revealed the sources of air masses and explained the different characteristics of the haze episodes in the four cities.

关键词： haze event thermal inversion layer atmospheric boundary layer Northeast China

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Composition-tuned optical properties of CdSe_(x)S_(1-x) and CdSe_(x)S_(1-x)/ZnS QDs

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Optoelectronics Letters 2022年第8期18卷 479-483页

作者： WU Feng ZHANG Siwen TIAN Zhu YU Wenhui SUN Shishuai li xiaolan Department of Physics School of ScienceTianjin University of TechnologyTianjin 300384China

The different compositions of the ternary alloyed CdSe_(x)S_(1-x)quantum dots(QDs)and CdSe_(x)S_(1-x)/ZnS core/shell quantum dots(CSQDs)have been synthesized by the chemical *** radii of these QDs were determined by transmission electron microscope(TEM).The optical properties of these QDs were investigated by the absorption and fluorescent *** was found that the absorption and fluorescent emissions were tuned by the component ratio,and the Commission Internationale de l´Eclairage(CIE)coordinates of the fluorescent spectra also depended on the *** with the CdSe_(x)S_(1-x)QDs,the CdSe_(x)S_(1-x)/ZnS CSQDs exhibit the fluorescence enhancement due to the surface passivation by shell *** composition-tuned optical properties may allow them to be used as fluorescent markers in biological imaging and to fabricate multicolor light emitting diode(LED).

关键词： CdSe_(x)S_(1-x) CdSe_(x)S_(1-x)/ZnS QDs

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