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| 1 | The impact of meteorological changes from 2013 to 2017 on PM2.5 mass reduction in key regions in China显示文摘In 2013,China issued the'Action Plan for the Prevention and Control of Air Pollution'('Ten Statements of Atmosphere')and implemented a series of pollution reduction measures from 2013 to 2017.In key regions of China,the mass concentrations of particulate matter with aerodynamic equivalent diameters less than 2.5μm(PM2.5)have dropped significantly.However,the contributions of meteorological changes to PM2.5 reduction are largely uncertain,which has attracted particular concern from the government and the public.Here,we investigated the impact of large-scale and boundary layer(BL)meteorological conditions on aerosol pollution and estimated the contributions of meteorological changes to PM2.5 reduction based on in-depth analysis and diagnosis of various observed meteorological elements and an integrated pollution-linked meteorological index(PLAM,which is approximately and linearly related to PM mass concentration).In this study,we found that the meteorological conditions worsened in 2014 and 2015 and improved in 2016 and 2017 relative to those in 2013 in key regions in China.In 2017 relative to 2013,only^5%(approximately 13%of the total PM2.5 decline)of the 39.6%reduction in PM2.5 mass concentrations can be attributed to meteorological changes in the Beijing-Tianjin-Hebei(BTH)region,and only^7%(approximately 20%of the total PM2.5 decline)of the 34.3%reduction can be attributable to meteorological changes in the Yangtze River Delta(YRD)region.Overall,the PM2.5 reduction due to meteorological improvement is much lower than the observed PM2.5 reduction in these areas,which indicates that emission reduction during the five-year implementation of the'Ten Statements of Atmosphere'is the dominant factor in the improvement in air quality.The changes in meteorology and climate are conducive to PM2.5 reduction but do not dominate the substantial improvement in air quality.Similar to the above regions,in the Pearl River Delta(PRD)region,the impact of meteorological changes on the annual averaged PM2.5 concentration from 2013 to2017 was relatively weak,and the PM2.5 reduction was mainly due to emission reductions.During winter 2017(January,February,and December of this year),the meteorological conditions improved-20%in the BTH region(observed total PM2.5reduction:40.2%)and-30%in the YRD region(observed total PM2.5 reduction:38.2%)relative to those in 2013,showing the meteorological factors played more important role in the decrease of PM2.5 in winter of these years in the two regions,respectively.The meteorological conditions in winter 2016 were 14%better than those in winter 2017,but the PM2.5 reduction in winter 2016 was still less than that in winter 2017,reinforcing the significant contributions of the increasing efforts to reduce PM2.5 emissions in 2017.The substantial progress of strict emission measures was also confirmed by a comparison of several persistent heavy aerosol pollution episodes(HPEs)with similar meteorological conditions.It is found that the decrease of PM2.5mass caused by emission reduction increases year by year,especially the decrease of PM2.5 concentration in 2016 and 2017.In China,HPEs mainly occur in winter,when meteorological conditions are approximately 40-100%worse than in other seasons.This worsening is partly due to the harbor effect of high topography,including downdrafts and the weak wind zone,and partly due to the increasingly stable regional BL structure caused by climate warming.For the formation of HPEs,it occurred under regional stagnant and stable conditions associated with upper-level circulation patterns,including the zonal westerly winds type and high-pressure ridges.After pollution formation,PM2.5 with mass accumulated to a certain degree can further worsen the BL meteorological conditions.The feedback effect associated with worsening conditions dominates PM2.5 mass explosive growth.In the context of high air pollutant emissions in China,unfavorable meteorological conditions are the necessary external conditions for the formation and accumulation of HPEs.Therefore,reducing aerosol pollution significantly during the earlier transport stage is critical in reducing persistent HPEs.Currently,even under favorable meteorological conditions,allowing emissions without restriction is also not advisable because aerosol pollution allowed to accumulate to a certain extent will significantly worsen the BL meteorological conditions and close the'meteorological channels'available for pollution dispersion. | Xiaoye ZHANG Xiangde XU Yihui DING Yanju LIU Hengde ZHANG Yaqiang WANG Junting ZHONG | 2019 | Science China Earth Sciences2019,62,12: | 42 |
| 2 | Expressions of cysteine-rich61,connective tissue growth factor and Nov genes in hepatocellular carcinoma and their clinical significance显示文摘AIM: To investigate the expression of cysteine-rich61 (Cyr61),connective tissue growth factor (CTGF) and nephroblastomaoverexpressecl gene (Nov) in hepatocellular carcinoma (HCC),and to evaluate the relationship between Cyr61, CTGF and Nov genes expression with invasion and metastasis of HCC.METHODS: Thirty-one HCC specimens were divided into small hepatocellular carcinoma (SHCC), nodular hepatocellular carcinoma (NHCC), solitary large hepatocellular carcinoma (SLHCC) according to their diameter and number of nodes. Reverse transcription polymerse chain reaction (RT-PCR) was used to detect the mRNA expression levels of Cyr61, CTGF and Nov genes in 31 resected specimens of hepatocellular carcinoma and para-cancerous normal liver tissues semi-quantitatively and the relation between their expression levels and clinical pathological parameters were compared.RESULTS: The expressions of Cyr61 and CTGF mRNA in carcinoma tissues were significantly higher than those in para-cancerous normal liver tissues (P<0.01). The expressions of Cyr61 and CTGF mRNA in HCC with venous invasion were higher than those in HCC without venous invasion. CTGF expression in HCC Edmondson's grade Ⅲ-IV was significantly higher than that in HCC Edmondson's grade I-II (P = 0.022). There was no obvious correlation between Nov mRNA and clinical-pathological features.Compared to NHCC, SLHCC had better cell differentiation,easier capsule formation, less microscopic venous invasion,milder liver cirrhosis. The expressions of Cyr61 and CTGF mRNA in NHCC were significantly higher than those in SLHCC and SHCC.CONCLUSION: Cyr61 and CTGF genes may play an important role in hepatocellular carcinogenesis and correlate with recurrence and metastasis of hepatocellular carcinoma.SLHCC has better biological behaviors than NHCC. | Zhi-JunZeng Lian-YueYang XiangDing WeiWang | 2004 | World Journal of Gastroenterology2004,10,23: | 28 |
| 3 | An emission source inversion model based on satellite data and its application in air quality forecasts显示文摘This paper aims at constructing an emission source inversion model using a variational processing method and adaptive nudging scheme for the Community Multiscale Air Quality Model (CMAQ) based on satellite data to investigate the applicability of high resolution OMI (Ozone Monitoring Instrument) column concentration data for air quality forecasts over the North China. The results show a reasonable consistency and good correlation between the spatial distributions of NO2 from surface and OMI satellite measurements in both winter and summer. Such OMI products may be used to implement integrated variational analysis based on observation data on the ground. With linear and variational corrections made, the spatial distribution of OMI NO2 clearly revealed more localized distributing characteristics of NO2 concentration. With such information, emission sources in the southwest and southeast of North China are found to have greater impacts on air quality in Beijing. When the retrieved emission source inventory based on high-resolution OMI NO2 data was used, the coupled Weather Research Forecasting CMAQ model (WRF-CMAQ) performed significantly better in forecasting NO2 concentration level and its tendency as reflected by the more consistencies between the NO2 concentrations from surface observation and model result. In conclusion, satellite data are particularly important for simulating NO2 concentrations on urban and street-block scale. High-resolution OMI NO2 data are applicable for inversing NOx emission source inventory, assessing the regional pollution status and pollution control strategy, and improving the model forecasting results on urban scale. | CHENG XingHong XU XiangDe DING GuoAn | 2010 | Science China Earth Sciences2010,53,5: | 17 |
| 4 | Role of AFP mRNA expression in peripheral blood as a predictor for postsurgical recurrence of hepatocellular carcinoma: A systematic review and meta-analysis显示文摘AIM: To identify the role of alpha-fetoprotein (AFP) mRNA expression in peripheral blood one week after surgery as a predictor for recurrence of hepatocellular carcinoma (HCC).METHODS: Published studies fulfilling the selection criteria were identified by searching several databases online. After a methodology assessment using a quality scale designed by European Lung Cancer Working Party, data in each research were aggregated by means of metaanalysis.RESULTS: Altogether 368 cases were included in the 9 selected studies, which fulfilled the selection criteria. The quality scores ranged from 35% to 84% with a median score of 55%. The 'design' subscore had the lowest median value (38%). By aggregating the data, a high χ2value (77.576) was presented. The fail-safe number was 136 and 64 for P = 0.05 and 0.01, respectively. CONCLUSION: AFP mRNA expression in peripheral blood 1 wk after surgery correlated with the recurrence of HCC and was a good predictor for tumor recurrence. | XiangDing Lian-YueYang Geng-WenHuang Jian-QingYang He-LiLiu WeiWang Ji-XiangPeng Jie-QuanYang Yi-MingTao Zhi-GangChang Xiu-ShouLing | 2005 | World Journal of Gastroenterology2005,11,17: | 15 |
| 5 | Spatial structure and scale feature of the atmospheric pollution source impact of city agglomeration显示文摘The spatial structure and multi-scale feature of the atmospheric pollution influence domain of Beijing and its peripheral areas (a rapidly developed city agglomeration) is dissected and analyzed in this paper on the basis of the atmospheric pollution dynamic-chemical process observation data of the urban building ensemble boundary layer of the Beijing City Air Pollution Observation Experiment (BECAPEX) in winter (February) and summer (August) 2003, and relevant meteorological elements and satellite retrieval aerosol optical depth (AOD), etc. comprehensive data with the dynamic-statistical integrated analysis of 'point-surface' spatial structure. Results show that there existed significant difference in the contribution of winter/summer different pollution emission sources to the component character of atmospheric pollution, and the principal component analysis (PCA) results of statistical model also indicate that SO2 and NOX dominated in the component structure of winter aerosol particle; instead, CO and NOX dominated in summer. Surface layer atmospheric dynamic and thermal structures and various pollutant species at the upper boundary of building ensembles at urban different observational sites of Beijing in winter and summer showed an 'in-phase' variation and its spatial scale feature of 'influence domain'. The power spectrum analysis (PSA) shows that the period spectrum of winter/summer particle concentration accorded with those of atmospheric wind field: the longer period was dominative in winter, but the shorter period in summer, revealing the impact of the seasonal scale feature of winter/summer atmospheric general circulation on the period of atmospheric pollution variations. It is found that from analyzing urban area thermal heterogeneity that the multiscale effect of Beijing region urban heat island (UHI) was associated with the heterogeneous expansion of tall buildings area. In urban atmospheric dynamical and thermal characteristic spatial structures, the turbulent scale feature of the urban boundary layer (UBL) of architectural complexes had important impact on the multi-scale feature of urban atmospheric pollution. The comprehensive analyses of the variational analysis field of Moderate Resolution Imaging Spectroradiometer (MODIS) AOD-surface PM10 under the condition of clear sky and the correlation resultant wind vector field for pollution source-tracing suggest that the emission sources for winter Beijing atmospheric pollution aerosols particle might be remotely traced to the south peripheral greater-scale spatial range of Hebei, Shandong, Tianjin, etc., and the spatial distribution of the high value area of AOD was associated with that of the high value area of resident family number (heating surface source). The backward trajectory feature of winter/ summer air particles exhibits analogous multi-scale feature, and depicts the difference in the scale feature of the pollution sources spatial distribution in different seasons. The peripheral source trajectory paths of urban atmospheric pollution (UAP) mainly come from the fixed industrial surface source or heating surface source in the outskirt of Beijing, and the diffusion and transport distance of peripheral sources in winter is larger than one in summer. The above conclusions depict the multi-scale spatial influence domain and seasonal features caused by UAP source influence and atmospheric dynamical structure. The high value area of the winter Total Ozone Mapping Spectrometer (TOMS) AOD lay in the Beijing region and its south peripheral area, an S-N zonal pattern, which reflects the dynamical effect of peripheral topographic pattern on the diffusion of regional scale atmospheric pollution sources. Study suggests that the extent of winter atmospheric pollution within the 'valley' megarelief in Beijing and periphery was close related with the pollution emission sources of the south peripheral area; and the significant 'anti-phase' variation feature of winter AOD and sunshine duration in Beijing and its peripheral areas, and regional scale correlation of low cloud cover, fog days, and aerosols reflects the local climatic effect of aerosol influence in this region. Besides, analysis of the impacts of atmospheric dry/wet deposition distributions within a valley-scale on the regional water body of Miyun reservoir also reveals the possible influence of the multi-scale spatial structure of summer water, soil and atmospheric pollution sources on the water quality of Miyun reservoir. | XU Xiangde ZHOU Xiuji SHI Xiaohui | 2005 | Science China Earth Sciences2005,48,z2: | 13 |
| 6 | Clinical analysis of the risk factors for recurrence of HCC and its relationship with HBV显示文摘AIM: To comprehend the risk factors of recurrence of hepatocellular carcinoma (HCC) and its relationship with the infection patterns of hepatitis B virus (HBV). METHODS: All materials of 270 cases of postoperative HCC were statistically analyzed by SPSS software. Recurrence and metastasis were classified into early (≤2 years) and late phase (>2 years). Risk factors for recurrence and metastasis after surgery in each group were analyzed.RESULTS: Out of 270 cases of HCC, 162 cases were followed up in which recurrence and metastasis occurred in 136 cases. There were a lot of risk factors related to recurrence and metastasis of HCC; risk factors contributing to early phase recurrence were serum AFP level, vascular invasion, incisal margin and operative transfusion, gross tumor classification and number of intrahepatic node to late phase recurrence. The HBV infective rate of recurrent HCC was 94.1%, in which 'HBsAg, HBeAb, HBcAb' positive pattern reached 45.6%. The proportion of HBV infection in solitary large hepatocellular carcinoma (SLHCC) evidently decreased compared to nodular hepatocellular carcinoma (NHCC) (P<0.05).CONCLUSION: The early and late recurrence and metastasis after hepatectomy of HCC were associated with different risk factors. The early recurrence may be mediated by vascular invasion and remnant lesion, the late recurrence by tumor's clinical pathology propert, as multicentric carcinogenesis or intrahepatic carcinoma denovo. HBV replication takes a great role in this process. From this study, we found that SLHCC has more satisfactory neoplasm biological behavior than NHCC. | Di-PengOu Lian-YueYang Geng-WenHuang Yi-MingTao XiangDing Zhi-GangChang | 2005 | World Journal of Gastroenterology2005,11,14: | 12 |
| 7 | The boundary layer characteristics in the heavy fog formation process over Beijing and its adjacent areas显示文摘By utilizing the Atmospheric Boundary Layer (ABL) observational data made available from the project '973' under the auspices of the Ministry of Science and Technology of the People's Republic of China - entitled the Beijing City Air Pollution Observation Field Experiment (BECAPEX), including the measurements by a wind profiler, captive airships, tower-based boundary layer wind and temperature gradient observational instruments (ultrasonic anemometers and electronic thermometers), air composition samplers, conventional upper-air, surface and Automatic Weather Stations (AWS) observations, this paper herewith analyzes, in a comprehensive manner, the occurrence of a heavy fog event over Beijing in February 2001, including its formation, development, persistence, dynamic and thermodynamic features as well as evolving stratification structures within the boundary layer at different stages. The results suggested: (i) as a typical case of urban heavy fog, before the fog onset over Beijing, a temperature inversion existed in the lower atmosphere, the smokes and the pollutants like SO2 and NO2 had been accumulated at a lower level. Proceeding the fog event, with the increase of SO2 and NO2 concentrations, condensability increased sharply. On the contrary, during the fog process, with increasing condensability, SO2 and NO2 concentrations decreased. This indicated that, acting as condensation nucleus, these accumulated pollutants were playing a key role in catalyzing the fog condensation. (ii) By analyzing mean gradient-, pulsation- and turbulence-distribution patterns derived from the wind measurements taken by the aforementioned tower-based instruments, they all indicated that about 10 hours before the fog onset, a signal foretelling potential strong disturbances in the lower boundary layer was detected, and a significant rise of both mean and disturbance kinetic energies was observed, revealing that the low-level wind shear was strengthened before the fog onset, consequently creating a favorable condition for the outbreak of turbulences. This strong signal seemed to be very meaningful in monitoring and predicting fog occurrence and its development. (iii) Once the fog was in shape, its condensation feedback effects tended to lift the height of temperature inversion layer within the mid and upper levels of the lower atmosphere, which in return determined the fog persistence and restructuring process. | ZHANG Guangzhi, BIAN Lingeng, WANG Jizhi, YANG Yuanqin, YAO Wenqing & XU Xiangde HWL of Chinese Academy of Meteorological Sciences, Beijing 10008, China National Meteorological Center, Beijing 100081, China | 2005 | Science China Earth Sciences2005,48,z2: | 12 |
| 8 | Vertical dynamic and thermodynamic characteristics of urban lower boundary layer and its relationship with aerosol concentration over Beijing显示文摘By utilizing observational data from a 325 m tower of the Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences (CAS) on March 19-29, 2001 and August 11-25, 2003, a comprehensive study was conducted on the vertical dynamical and thermodynamic characteristics of the urban lower boundary layer (ULBL) and its relationship with aerosol concentration over Beijing. Firstly, a comparative analysis was made on the gradient data (wind, temperature and humidity), ultrasonic data (atmospheric turbulences) and air-quality observations at different tower heights (47, 120 and 280 m). Secondly, a diagnosis was made to reveal the major features of normalized variances of velocity and temperature, turbulence kinetic energy as well as their relationship with aerosol concentrations. Furthermore, the characteristics of the ULBL vertical structure and the TSP concentration/distribution variations during a sand/dust weather process were also analyzed. The outcome of the study showed that under unstable stratification, the normalized variances of velocity (σu/u*, σv/u*, σw/u*) and temperature (σT/T*) at 47 and 120 m heights fit the Monin-Obukhov similarity (MOS) framework and the fitting formulas were given out accordingly. According to the stratification parameter (z′/L), the stable ULBL could be divided into 2 zones. With z′/L<0.1, it was a weakly stable zone and MOS framework was applicable. The other was a highly stable zone with z′/L>0.1 and the normalized velocity variances tended to increase along with higher stability, but it remained constant for normalized temperature variances. At daytime, the near-surface layer includes two heights of 47 and 120 m, while 280 m has been above it. The ULBL analysis in conjunction with a sand/dust weather process in Beijing in March 2001 indicated that the maximum concentration of Total Suspended Particulates (TSP) at 320 m reached 913.3 μg/m3 and the particles were transported from the upper to lower ULBL, which was apparently related to the development process of a low-level jet and its concomitant strong sinking motion. | ZHOU Mingyu, YAO Wenqing, XU Xiangde & YU Haiqing State Key Laboratory on Severe Weather, Chinese Academy of Meteorological Sciences, Beijing 100081, China National Marine Environment Forecasting Center, Beijing 100081, China National Meteorological Center, Beijing 100081, China | 2005 | Science China Earth Sciences2005,48,z2: | 11 |
| 9 | Land-surface processes and summer-cloud-precipitation characteristics in the Tibetan Plateau and their effects on downstream weather:a review and perspective显示文摘Correct understanding of the land-surface processes and cloud-precipitation processes in the Tibetan Plateau(TP)is an important prerequisite for the study and forecast of the downstream activities of weather systems and one of the key points for understanding the global atmospheric movement.In order to show the achievements that have been made,this paper reviews the progress on the observations for the atmospheric boundary layer,land-surface heat fluxes,cloud-precipitation distributions and vertical structures by using ground-and space-based multiplatform,multisensor instruments and the effect of the cloud system in the TP on the downstream weather.The results show that the form drag related to the topography,land-atmosphere momentum and scalar fluxes is an important part of the parameterization process.The sensible heat flux decreased especially in the central and northern TP caused by the decrease in wind speeds and the differences in the ground-air temperatures.Observations show that the cloud and precipitation over the TP have a strong diurnal variation.Studies also show the compressed-air column in the troposphere by the higher-altitude terrain of the TP makes particles inside clouds vary at a shorter distance in the vertical direction than those in the non-plateau area so that precipitation intensity over the TP is usually small with short duration,and the vertical structure of the convective precipitation over the TP is obviously different from that in other regions.In addition,the influence of the TP on severe weather downstream is preliminarily understood from the mechanism.It is necessary to use model simulations and observation techniques to reveal the difference between cloud precipitation in the TP and non-plateau areas in order to understand the cloud microphysical parameters over the TP and the processes of the land boundary layer affecting cloud,precipitation and weather in the downstream regions. | Yunfei Fu Yaoming Ma Lei Zhong Yuanjian Yang Xueliang Guo Chenghai Wang Xiaofeng Xu Kun Yang Xiangde Xu Liping Liu Guangzhou Fan Yueqing Li Donghai Wang | 2020 | National Science Review2020,7,3: | 10 |
| 10 | Regional characteristics of the interdecadal turning of winter/summer climate modes in Chinese mainland显示文摘Tomé and Miranda’s climate trend turning discriminatory model is used to identify the spatial-temporal characteristics of the interdecadal turning of winter/summer climate modes at stations and in eight sub-areas over Chinese mainland based on the 1961–2000 observations. It is found that the stations with close occurrence years of the interdecadal trend turning (ITT) and coincident trends after the ITT exhibit a zonal distribution. A view is accordingly proposed that the interdecadal turnings of climate modes in China have remarkably regional structures. The research results show that after the early 1980s, winter climate over Chinese mainland overall trends towards a “warm-wet” mode, while summer climate had an abrupt change into “warm wet” mode in the late 1980s, suggesting that the time of the “warm-wet” mode turning for winter climate is earlier than that for summer climate. The regional characteristics and test results of the ITTs in eight sub-areas suggest that winter climate exhibits a distinctive “warm-dry” trend in North China after the late 1970s, and a slight “warm-dry” trend in Northeast China, South China, and Southwest China after the late 1980s. A “warm-wet” trend appears in the rest four sub-areas (the middle and lower reaches of the Yangtze River and the Huaihe River Valley, briefly Jianghuai, the east of the Tibetan plateau, and the east and west of Northwest China) after the early 1980s. The summer climate trends towards a “warm-dry” mode in Northeast China, North China and the east of Northwest China after the late 1980s, but a “warm-wet” mode appears in Southwest China and the east of the Tibetan plateau after the middle 1970s, as well as in Jianghuai and the west of Northwest China after the early 1980s. Specially, summer climate in South China started a “cold-wet” trend in 1984. | SHI XiaoHui XU XiangDe | 2007 | Chinese Science Bulletin2007,52,1: | 9 |
| 11 | Extreme precipitation events in East China and associated moisture transport pathways显示文摘Interannual variation of summer precipitation in East China, and frequency of rainstorms during the monsoon season from 1961 to 2010, are analyzed in this study. It is found that the two variables show opposite trends on a decadal time scale: frequency of rainstorms increases significantly after the 1990 s, while summer precipitation in East China decreases during the same period. Analysis of the spatial distribution of summer rainstorm frequency from 1961 to 2010 indicates that it decreases from the southeast to the northwest at the east edge of the large-scale topography associated with the plateaus. Spatial distribution of rainstorms with daily rainfall greater than 50 mm is characterized by a 'high in the southeast and low in the northwest' pattern, similar to the staircase distribution of the topography. However, the spatial distribution of variation in both summer precipitation and frequency of extreme rainstorms under global warming differs significantly from the three-step staircase topography. It is shown that moisture characteristics of summer precipitation and extreme rainstorms during the monsoon season in East China, including moisture transport pathways, moist flow pattern, and spatial structure of the merging area of moist flows, differ significantly. Areas of frequent rainstorms include the Yangtze River Valley and South China. Column-integrated moisture transport and its spatial structure could be summarized as a 'merging' of three branches of intense moist flows from low and middle latitude oceans, and 'convergence' of column-integrated moisture fluxes. The merging area for moist flow associated with rainstorms in the high frequency region is located slightly to the south of the monsoonal precipitation or non-rainstorm precipitation, with significantly strong moisture convergence. In addition, the summer moist flow pattern in East China has a great influence on the frequency of extreme rainstorms. Moisture flux vectors in the region of frequent rainstorms correspond to vortical flow pattern. A comparison of moisture flux vectors associated with non-rainstorms and rainstorms indicates that the moist vortex associated with rainstorms is smaller in size and located to the south of the precipitation maximum, while the moist vortex associated with non-rainstorms is larger and located to the north. It is shown that column-integrated moist transport vortices and the structure of moist flux convergence have significant impacts on the north-south oscillation of frequent rainstorm areas in East China, which is synchronized with the maximum vorticity of moisture transport and the minimum of convergence on the decadal time scale. Synthesis of moisture transport pathways and related circulation impacts leads to a conceptual model of moisture flow associated with rainstorms. | ZHAO Yang XU XiangDe ZHAO TianLiang XU HongXiong MAO Fei SUN Han WANG YuHong | 2016 | Science China Earth Sciences2016,59,9: | 8 |
| 12 | Aerosol influence domain of Beijing and peripheral city agglomeration and its climatic effect显示文摘The aerosol distribution in Beijing and peripheral cities agglomeration (BPCA) and its re- gional climatic effect are investigated on the basis of the statistical analyses of satellite Total Ozone Map- ping Spectrometer (TOMS) retrieval aerosol optical depth (AOD) and the meteorological data of sunshine duration, fog days, and low cloud cover, observed at Beijing and its peripheral meteorological stations. The analysis on multi-samples variational correction of the satellite remote sensing Moderate Resolution Imaging Spectroradiometer (MODIS) AOD under the clear sky and stable weather condition in conjunction with surface observations reveal that there was a “triangle-like” distribution pattern of the high values of aerosols in the southern “valley” of the “U-shape” megarelief of Beijing and its peripheral areas. The distribution pattern suggests that the large-scale transfer and diffusion of city agglomeration pollutants might form a relatively persistent characteristic spatial distribution of city agglomeration pollutants much larger than city-scale. Under the background of the particular megarelief effect of Beijing and periph- eral areas, the high value area of TOMS AOD, as well as regional correlation distribution between clear sky sunshine duration and TOMS AOD are also similar to the composite image of MODIS AOD variational fields, that is to say, the effect of atmospheric aerosols was very distinctive in Beijing and peripheral areas. The high value area of the negative correlation between clear sky sunshine duration and TOMS AOD ap-proximately accorded with the significant negative value area of the sunshine duration deviations of the 1980s to the 1990s, and the daily variations of the AOD also showed an anti-phase relation with those of clear sky sunshine duration. The above high cor- relation area of the urban aerosol impact of Beijing- Tianjin region leant towards south peripheral area, with its “center of gravity” in the south of Beijing- Tianjin agglomeration, and the main body of the high correlation area prolongating southwards, forming an aerosol influence domain of “eccentric ellipse” shape, that is to say, there was an aerosol influence domain of some “radius” in Beijing City and its peripheral areas, within and outside which sunshine duration, low cloud cover, and fog days showed a remarkable difference in interannual variation trend. At the downstream of the city agglomeration there was a significant interdecadal increment area of fog or low cloud cover, which might be associated with the local climatic feature of the regional flow convergent field in the diffusion process of city agglomeration pollut- ants in the aerosol influence domain, and such a local dynamical convergence feature might lead to the regional exacerbation of aerosol impact downstream of the city agglomeration. The research result reveals that the significant area of interdecadal change rate of low cloud cover within the aerosol influence do- main is correlated with the regional strengthening effect of aerosol impact of the local wind structure in the “downstream plume area” of the city. | XU Xiangde SHI Xiaohui ZHANG Shengjun DING Guoan MIAO Qiuju ZHOU Li | 2006 | Chinese Science Bulletin2006,51,16: | 8 |
| 13 | 8-Bromo-7-methoxychrysin-blocked STAT3/ Twist axis inhibits the sternness of cancer stem cell-like cell originated from SMMC-7721 cells显示文摘抄写 3 的信号变换器和使活跃之物(STAT3 ) 是能调整房间增长,幸存,和开发的潜伏的细胞质的 transcriptional 因素的家庭的一个成员。扭曲是 STAT3 的目标基因,这被报导了,并且发信号的 STAT3/Twist 在调整癌症进步起一个重要作用。这里,探索 8-bromo-7-methoxychrysin (BrMC ) 是否禁止肝癌症经由破坏 STAT3/Twist 发信号的像茎的房间(LCSLC ) 性质,我们在 vitro 的有教养的 SMMC-7721 房间,并且由决定形成范围的能力和迁居在球状体的 stemness 上评估了 BrMC 的效果。范围形成试金结果在 LCSLC 显示出形成范围的能力的集中依赖者减少(P < 0.05 ) 与 BrMC 的不同集中对待。愈合创伤的试金结果在与 BrMC 的不同集中对待的 LCSLC 的房间移植表明了集中依赖者衰落。另外, CD133, CD44,和 ALDH1 层次在与 BrMC 对待的 LCSLC 被减少。有 BrMC 的不同集中的治疗也减少了 p-STAT3 和 Twist1 蛋白质的表情。BrMC 的效果被合作处理实质地与 JSI-124 提高, STAT3 的一个特定的禁止者。Twist1 的宫外的表示在 LCSLC 在标记的范围形成,移植,和表示上稀释了 BrMC 的禁止的效果。然而,它不有在 LCSLC 在 p-STAT3 上影响表示。这些结果证明 BrMC 禁止 LCSLC 的 stemness 由禁止 STAT3/Twist 从 SMMC-7721 房间线发源信号轴。 | Yimin Luo Yinghong Cui Xiaocheng Cao Xiang Li A Chen Jiansong Zhang Xiangding Chen Jianguo Cao | 2017 | Acta Biochimica et Biophysica Sinica2017,49,5: | 7 |
| 14 | Study on variational aerosol fields over Beijing and its adjoining areas derived from Terra-MODIS and ground sunphotometer observation显示文摘This paper presents a comprehensive observa-tion technique on derived aerosols data from mobile sun-photometer graph and Terra-Moderate Resolution Imaging Spectroradiometer (MODIS) observation. Research results suggest that after being treated by the variational technique with respect to sunphotometer observations, the Terra- MODIS remote sensing aerosol data are remarkably im-proved, thus for the first time revealing features of the influ-ence of aerosols and pollution emissions of Beijing and its adjoining areas (Hebei, Shandong, etc. provinces). The re-gional impact features of aerosols are related with the pe-ripheral U-shape topography of Beijing. Analyses with Hy-brid Single Particle Lagrangian Integrated Trajectory model (HYSPLIT-4) and meteorological data in the case studied confirm the pollutants diffusion process along the trajectory from the sources in the south-west region, and the regional aerosol impact features. | XU Xiangde ZHOU Xiuji WENG Yonghui TIAN Guoliang LIU Yujie YAN Peng DING Guoan ZHANG Yuxiang MAO Jietai QIU Hong | 2003 | Chinese Science Bulletin2003,48,18: | 7 |
| 15 | How is mRNA expression predictive for protein expression? A correlation study on human circulating monocytes显示文摘在学习 mRNA 表示的一个关键假设是它在蛋白质表示的预言是增进知识的。然而,仅仅有限的研究在酵母探索了 mRNA 蛋白质表示关联或人的纸巾和结果是相对不一致的。我们从 30 个无关的女人在刚孤立的人的传播单核白血球在 mRNA 蛋白质表情上执行了关联分析。为 71 基因的表示蛋白质被确定并且由结合的 2-D 电气泳动识别了集体 spectrometry。相应 mRNA 表达式被 Affymetrix 基因芯片确定。重要关联(r=0.235, P < 0.0001 ) 包括所有学习基因和所有样品为整个数据集被观察。关联在基因本体论的不同生物范畴变化了。例如,最高的关联以细胞的部件为细胞外的区域的基因被完成(r=0.643, P < 0.0001 ) 并且最低关联为规定的基因被获得(r=0.099, P=0.213 ) 以生物过程。在染色体,样品的一半证明为 71 基因的重要积极关联和重要关联在所有样品在平均 mRNA 和平均蛋白质表示层次之间被发现(r=0.296, P < 0.01 ) 。在学习组水平,然而,仅仅五学习基因越过所有样品有重要积极关联。我们的结果显示出在 mRNA 和蛋白质表示层次之间的全面积极关联。然而,中等、变化的关联建议那 mRNA 表情可能有时是有用的,但是远非当然在预言蛋白质表示层次完善。 | Yanfang Guo Peng Xiao Shufeng Lei Feiyan Deng Gary Guishan Xiao Yaozhong Liu Xiangding Chen Liming Li Shan Wu Yuan Chen Hui Jiang Lijun Tan Jingyun Xie Xuezhen Zhu Songping Liang Hongwen Deng | 2008 | Acta Biochimica et Biophysica Sinica2008,40,5: | 7 |
| 16 | Analysis to significant climate change in aerosol influence domain of Beijing and its peripheral areas by EOF mode显示文摘Using the total ozone mapping spectrometer (TOMS) aerosol optical depth (AOD)data and the sunshine duration, fog days, Iow cloud cover (LCC), etc. meteorological data in 1979-2000 in North China, as well as empirical orthogonal function (EOF) mode statistical analyses method, the winter aerosol distributive character of Beijing and peripheral city agglomeration and its influence effect on regional climate are investigated in this paper, especially the relation between aerosol influence effect and distinct change regions of eigenvectors of EOF mode. It is found from analyzing the regional distribution of the long-term averaged winter TOMS AOD that there is a large-scale relatively stable high value zone of aerosol concentration in the valley of the Beijing and peripheral U-shape megarelief. A high correlation area of AOD between Beijing and its southern peripheral exists in winter, and in this significant region of aerosol interaction, there is 'in-phase' character of the interannual variations of winter AOD, fog days, and LCCs. It indicates that the variations of aerosol in Beijing and its peripheral areas have impacts on interannual changes of fog days and LCCs in this area. The EOF analyses of the meteorological data further reveal the climate change regions and long-term trends of winter sunshine duration-reducing, and LCC- and fog days-increasing in North China. The areas of significant changes of the first EOF eigenvectors (FEE) of sunshine duration, fog days, LCCs almost superpose on corresponding marked regions of interdecadal differences between the 1990s and 1980s, and all accord with the S-N zonal high value pattern and high correlation region of winter AOD in Beijing and its peripheral areas. Interannual variations of their associated time coefficients (ATC) are in phase with that of regional mean AOD, and both of them have a secular rising trend. Results by EOF mode analyses depict the regional climatic change principal character of winter sunshine duration-reducing, and LCC- and fog days-increasing in peripheral areas to the south of Beijing, and reveal the regional influence effect of aerosol, i.e. the high value zone of long-term averaged winter AOD, significant change regions of FEE of sunshine duration, fog days, and LCC all lie in peripheral city agglomeration to the south of Beijing. These distributive features above suggest that there exists a regional strengthening trend of aerosol climatic effect within influence domain in peripheral city agglomeration to the south of Beijing. | SHI Xiaohui, XU Xiangde, ZHANG Shengjun & DING Guoan State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing 100081, China Nanjing University of Information Science and Technology, Nanjing 210044, China | 2005 | Science China Earth Sciences2005,48,z2: | 5 |
| 17 | RADIAL GROWTH OF HUASHAN PINE AND ITS RESPONSE TO CLIMATE显示文摘Huashan pine (Finus armandii Franch) is a poential species for dendroclimatic study. Ring-width cores were sampled for four stands of two sites from the eastern extreme of the Qinling Mountains. The ring-width chronologies developed in this study cover a maximum Period from A.D. 1359 t0 1992 and show high common chronology variance over the common period 1911-1960.All the chronologies are significantly correlated with all others, and the degree of correlation appears related to tree age. Response function analyses reveal that from 41 to 75 Percent of chronology variance can be accounted for by monthly mean air temperature and monthly total precipitation. A sufficiently strong correlation of ringwidth index with May and June rainfall and June temperature exists, implying soil moisture to be a limiting factor for Huashan pine growth. The association displayed by response diagrams between narrow rings, low precipitation, and high temperature during spring and early summer indicates a promising potential of ring widths for reconstruction of spring drought for the study area. | Shao Xuemei, Wu Xiangding(Institute of Geography, CAS, Beijing 100101 People’s Republic of China)Xi’an Laboratory of Loess and Quaternary Geology, CAS,xi’an 710061 People’s Republic of China) | 1994 | Journal of Geographical Sciences1994,4,Z2: | 5 |
| 18 | ADAM17 mRNA expression and pathological features of hepatocellular carcinoma显示文摘AIM: To study the expression of a disintegrin and metalloproteinase 17 (ADAM17) mRNA in hepatocellular carcinoma (HCC) and to evaluate the relationship between ADAM17 mRNA expression and clinicopathological featuresof HCC.METHODS: Hepatocellular carcinomas (HCC) from 31 cases were divided into small HCC (SHCC), nodular HCC (NHCC)and solitary large HCC (SLHCC) according to tumor diameter and the number of nodes. ADAM17 mRNA expressions were compared among those groups by means of semi-quantitative reverse transcription polymerase chain reaction (RT-PCR).The relationship between ADAM17 mRNA expression level and clinicopathological features of HCC was evaluated.RESULTS: NHCC had lower differentiation and was more frequently of microvascular invasion (10/12) than SHCC(3/11) and SLHCC (3/8) (P<0.05), but no statistical difference was observed between SHCC and SLHCC comparing their clinicopathological features. ADAM17 mRNA expression was detected in 77.4% (24/31) of HCC tissues and was significantly higher than that in paired non-cancerous liver tissues in which only 35.5% (11/31) of the samples were detected of the expression (P<0.05). The expression of ADAM17 mRNA was much higher in NHCC than in SHCC and SLHCC(P<0.05), while no significant difference was discovered between SHCC and SLHCC. The quantities of ADAM17 mRNA were significantly higher in poorly differentiated HCC than in well or moderately differentiated HCC, but no statistical difference was found concerning liver cirrhosis,tumor capsule formation or microvascular invasion of the cancer.CONCLUSION: The increased expression of ADAM17 may play a key role in the development of HCC. The expression levels of ADAM 17 mRNA varied among different pathological types of HCC. Lower mRNA expression of ADAM17 mRNA in SLHCC may be associated with the better molecular pathological features of SLHCC. | XiangDing Lian-YueYang Gen-WenHuang WeiWang Wei-QunLu | 2004 | World Journal of Gastroenterology2004,10,18: | 5 |
| 19 | Structures of convection and turbulent kinetic energy in boundary layer over the southeastern edge of the Tibetan Plateau显示文摘Based on a comprehensive analysis on Sonic Anemometer and gradient data, wind profile radar(WPR) and GPS sounding data of March–August 2008 from the boundary layer(BL) tower observation system at Dali on the southeastern edge of Tibetan Plateau(TP), it is found that the strengths of turbulent kinetic energy(TKE), buoyancy term and shear term depend on vegetation cover in association with local stability and thermodynamic condition. Strong kinetic turbulence appears when near surface layer in neutral condition with the large contribution from shear term. In an unstable condition within near surface layer, the atmospheric turbulent motion is mainly thermal turbulence, as buoyancy term is obviously larger than shear term. Under a stable condition the intermittent turbulence is accompanied by weak shear and buoyancy term, and TKE is significantly less than neutral or instable condition. The study also presents that the buoyancy term contribution at Nyingchi station in the southern slopes of the TP large topography in spring is significantly larger than that at Dali over the southeastern TP edge, reflecting that the thermal turbulence makes an important contribution to convection activity in the southern slopes of TP. Dali station is located in complex terrain with mountain and valley leading to larger kinetic turbulence. From the perspective of interaction of turbulence-convection in different scales, the study revealed that the height of convective boundary layer(CBL) could reach up to 1500–2000 m. TKE, shear term, and buoyancy term in near surface layer have the notable correlations with BL height and local vertical motion. The daytime thermodynamic turbulence effect of heat flux and buoyancy term has an obvious impact on the height of CBL, whereas mechanical turbulence only exerts a less impact. Mechanical turbulence in near surface layer has a significant impact on vertical motion especially in the forenoon with impacting height of 2500–3000 m. The peaks in diurnal variations of shear term and buoyancy term correspond to the high instable periods, especially in summer forenoon. Our observation analysis characterized the convection activity triggered by TKE source and their interaction in the southeastern TP edge. | WANG YinJun XU XiangDe ZHAO TianLiang SUN JiHua YAO WenQing ZHOU MingYu | 2015 | Science China Earth Sciences2015,58,7: | 4 |
| 20 | The Tibetan Plateau Surface–Atmosphere Coupling System and Its Weather and Climate Effects: The Third Tibetan Plateau Atmospheric Science Experiment显示文摘The Tibetan Plateau(TP) is a key area affecting forecasts of weather and climate in China and occurrences of extreme weather and climate events over the world. The China Meteorological Administration, the National Natural Science Foundation of China, and the Chinese Academy of Sciences jointly initiated the Third Tibetan Plateau Atmospheric Science Experiment(TIPEX-Ⅲ) in 2013, with an 8–10-yr implementation plan. Since its preliminary field measurements conducted in 2013, routine automatic sounding systems have been deployed at Shiquanhe, Gaize, and Shenzha stations in western TP, where no routine sounding observations were available previously. The observational networks for soil temperature and soil moisture in the central and western TP have also been established. Meanwhile, the plateau-scale and regional-scale boundary layer observations, cloud–precipitation microphysical observations with multiple radars and aircraft campaigns, and tropospheric–stratospheric air composition observations at multiple sites, were performed. The results so far show that the turbulent heat exchange coefficient and sensible heat flux are remarkably lower than the earlier estimations at grassland, meadow, and bare soil surfaces of the central and western TP. Climatologically, cumulus clouds over the main body of the TP might develop locally instead of originating from the cumulus clouds that propagate northward from South Asia. The TIPEX-Ⅲ observations up to now also reveal diurnal variations, macro-and microphysical characteristics, and water-phase transition mechanisms, of cumulus clouds at Naqu station. Moreover, TIPEX-Ⅲ related studies have proposed a maintenance mechanism responsible for the Asian 'atmospheric water tower' and demonstrated the effects of the TP heating anomalies on African, Asian, and North American climates. Additionally, numerical modeling studies show that the Γ distribution of raindrop size is more suitable for depicting the TP raindrop characteristics compared to the M–P distribution, the overestimation of sensible heat flux can be reduced via modifying the heat transfer parameterization over the TP, and considering climatic signals in some key areas of the TP can improve the skill for rainfall forecast in the central and eastern parts of China. Furthermore, the TIPEX-Ⅲ has been promoting the technology in processing surface observations, soundings, and radar observations, improving the quality of satellite retrieved soil moisture and atmospheric water vapor content products as well as high-resolution gauge–radar–satellite merged rainfall products, and facilitating the meteorological monitoring, forecasting, and data sharing operations. | Ping ZHAO Yueqing LI Xueliang GUO Xiangde XU Yimin LIU Shihao TANG Wenming XIAO Chunxiang SHI Yaoming MA Xing YU Huizhi LIU La JIA Yun CHEN Yanju LIU Jian LI Dabiao LUO Yunchang CAO Xiangdong ZHENG Junming CHEN An XIAO Fang YUAN Donghui CHEN Yang PANG Zhiqun HU Shengjun ZHANG Lixin DONG Juyang HU Shuai HAN Xiuji ZHOU | 2019 | Journal of Meteorological Research2019,33,3: | 4 |