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| 1 | Accuracy assessment of global historical cropland datasets based on regional reconstructed historical data——A case study in Northeast China显示文摘Historical cropland datasets are fundamental for quantifying the effects of human land use activities on climatic change and the carbon cycle. Two representative global land-use datasets, the Global Land Use Database (termed SAGE dataset) and the Historical Database of the Global Environment (termed HYDE dataset) have been established and used widely. Despite improvement of data quality and methodologies for extracting historical land use information, certain dataset limitations exist that need to be quantified and communicated to users so that they can make informed decisions on whether and how these land-use products should be used. The Cropland data of Northeast China (CNEC) is based on calibrated historical data and a multi-sourced data conversion model, and reconstructs cropland cover change in Northeast China over the last 300 years. Us- ing the CNEC as a reference, we evaluated the accuracy of cropland cover for SAGE and HYDE in Northeast China at spatial scales ranging from the entire Northeast China to provinces and even individual raster grid cells. Neither SAGE nor HYDE reflects real historical land reclamation. Cropland areas in SAGE are overestimated by 20.98 times in 1700 to 1.6 times in 1990. Although HYDE is better, there are significant disagreements in cropland area and distribution between HYDE and CNEC, especially in the 18th and 19th centuries. The proportion of total grid cells whose relative error was greater than 100% was 63.55% in 1700 and 53.27% in 1780. Global cropland dataset errors over Northeast China originate mainly from both the reverse calculation method for historical cropland data based on modern spatial patterns, and modern land-use outputs from satellite data. | Li BeiBei Fang XiuQi Ye Yu Zhang XueZhen | 2010 | Science China Earth Sciences2010,53,11: | 31 |
| 2 | Comparisons of cropland area from multiple datasets over the past 300 years in the traditional cultivated region of China显示文摘陆地使用 / 盖住变化是在气候和生态的模拟的一个重要参数。尽管他们广泛地在社区,半自动地面防空系统数据集和 HYDE 数据集被使用了,二代表性的全球历史的陆地使用数据集,很少在地区性的规模关于他们的精确性被估计。这里,我们为中国(TCRC ) 的传统的栽培区域执行了一些评价在上持续 300 年,由把 SAGE2010 和 HYDE (v3.1 ) 与中国历史的农田数据集(CHCD ) 作比较。比较在三空间规模被执行:由 60 km 格子房间的全部学习区域,省的区域和 60 km。结果证明(1 ) 从 SAGE2010 的农田区域从 CHCD 是多于那的大部分;而且,以在 1950 以后的从 1700 ~ 1950 和 0.34% 的 0.51% 的率的生长从 CHCD 与那也不一致。(2 ) HYDE 数据集(v3.1 ) 在全部学习区域上比半自动地面防空系统数据集接近了 CHCD 数据集。然而,大偏爱能被 60 km 格子房间规模在省的规模和 60 km 检测。有比70%大的偏爱的格子房间的百分比(<-70%或>70%)并且90%(<-90%或>90%)当那些有的偏爱为仅仅5%6%从10%~10%并且从30%~30%报道 时,分别地说明了全部的格子房间的56%63%和40%45%并且17%全部的格子房间分别地。(3 ) 用本地历史的档案,有高精确性的历史的数据集将是改进气候和生态的模拟的精确性的一个珍贵方法重建。 | HE Fanneng LI Shicheng ZHANG Xuezhen GE Quansheng DAI Junhu | 2013 | Journal of Geographical Sciences2013,23,6: | 21 |
| 3 | Cropland cover change in Northeast China during the past 300 years显示文摘Land use/cover change induced by human activities has emerged as a 'global' phenomenon with Earth system consequences. Northeast China is an area where the largest land cultivation activities by migrants have happened in China during the past 300 years. In this paper, methods including documentary data calibration and multi-sourced data conversion model are used to reconstruct historical cropland cover change in Northeast China during the past 300 years. It is concluded that human beings have remarkably changed the natural landscape of the region by land cultivation in the past 300 years. Cropland area has increased almost exponentially during the past 300 years, especially during the past 100 years when the ratio of cropland cover changed from 10% to 20%. Until the middle of the 19th century, the agricultural area was still mainly restricted in Liaoning Province. From the late 19th century to the early 20th century, dramatic changes took place when the northern boundary of cultivation had extended to the middle of Heilongjiang Province. During the 20th century, three agricultural regions with high ratio of cropland cover were formed after the two phases of spatial expansion of cropland area in 1900s—1930s and 1950s—1980s. Since 1930s—1940s, the expansion of new cultivated area have invaded the forest lands especially in Jilin and Heilongjiang Provinces. | YE Yu FANG XiuQi REN YuYu ZHANG XueZhen CHEN Li | 2009 | Science China Earth Sciences2009,52,8: | 21 |
| 4 | Leaching ion adsorption rare earth by aluminum sulfate for increasing efficiency and lowering the environmental impact显示文摘The leaching efficiency(LE) of ion adsorption rare earth(IARE) by the sulfate and chloride of ammonium,magnesium and aluminum were comparatively determined using column leaching method. It is found that at equal equivalent concentration of cation, the LE of IARE by aluminum sulfate is the highest, and the zeta potential of clay mineral particles in the tailing is near to zero, which means a lower risk of landslide and pollutant emission. Furthermore, the optimum concentration of aluminum sulfate is determined to be0.02 mol/L, which is much lower than that of ammonium sulfate and magnesium sulfate. To reduce the production cost and environmental impact, we proposed a multi-stage leaching process, which was firstly leaching with ammonium sulfate and then with aluminum sulfate, following by water washing and lime neutralizing. With the ratio of ammonium sulfate to aluminum sulfate varying from 1:0 to 0.5:0.5, the residual ammonium in tailing decreases from 11.2% to 0.6%, however, the LE of RE shows an optimum value at 0.8:0.2. By neutralizing the pH of tailing with lime water to over 6, the ion concentration in water rinsing solution can meet the requirement for water discharge. At the same time, the zeta potential of clay particles is found to be around-5 mV, means a relatively lower risk of landslide. These facts indicate that the LE of IARE can be increased and the danger caused by tailings landslides and pollutant emissions can be reduced by replacing ammonium sulfate with aluminum sulfate as leaching reagent. | Lifen Yang Cuicui Li Dashan Wang Fengyang Li Yanzhu Liu Xuezhen Zhou Mingbiao Liu Xiufeng Wang Yongxiu Li | 2019 | Journal of Rare Earths2019,37,4: | 19 |
| 5 | Rates of temperature change in China during the past 2000 years显示文摘Using 24 proxy temperature series,the rates of temperature change in China are analyzed at the 30-to 100-year scales for the past 2000 years and at the 10-year scale for the past 500 years.The results show that,at the 100-year scale,the warming rate for the whole of China in the 20th century was only 0.6±1.6°C/100 a (interval at the 95% confidence level,which is used hereafter),while the peak warming rate for the period from the Little Ice Age (LIA) to the 20th century reached 1.1±1.2°C/100 a,which was the greatest in the past 500 years and probably the past 2000 years.At the 30-year scale,warming in the 20th century was quite notable,but the peak rate was still less than rates for previous periods,such as the rapid warming from the LIA to the 20th century and from the 270s-290s to 300s-320s.At the 10-year scale,the warming in the late 20th century was very evident,but it might not be unusual in the context of warming over the past 500 years.The exact timing,duration and magnitude of the warming peaks varied from region to region at all scales.The peak rates of the 100-year scale warming in the AD 180s-350s in northeastern China as well as those in the 260s-410s and 500s-660s in Tibet were all greater than those from the mid-19th to 20th century.Meanwhile,the rates of the most rapid cooling at scales of 30 to 100 years in the LIA were prominent,but they were also not unprecedented in the last 2000 years.At the 10-year scale,for the whole of China,the most rapid decadal cooling in the 20th century was from the 1940s to 1950s with a rate of 0.3±0.6°C/10 a,which was similar to rates for periods before the 20th century.For all regions,the rates of most rapid cooling in the 20th century were all less than those for previous periods. | GE QuanSheng ZHANG XueZhen HAO ZhiXin ZHENG JingYun | 2011 | Science China Earth Sciences2011,54,11: | 17 |
| 6 | Experimental research on electrochemical machining of titanium alloy Ti60 for a blisk显示文摘Ti60(Ti–5.6Al–4.8Sn–2Zr–1Mo–0.35Si–0.7Nd) is a high-temperature titanium alloy that is now used for important components of aircraft engines. Electrochemical machining(ECM) is a promising technique that has several advantages, such as a high machining rate, and can be used on a wide range of difficult-to-process materials. In this paper, orthogonal experiments are conducted to investigate ECM of Ti60, with the aim of determining the influences of some electrochemical process parameters on the surface roughness. The most important parameter is found to be the frequency of the pulsed power supply. It is found that using suitably optimized parameters for ECM can greatly decrease the surface roughness of a workpiece. A surface roughness of approximately 0.912 lm can be obtained with the following optimal parameters: Na Cl electrolyte concentration 13wt%, voltage20 V, pulse frequency 0.4 k Hz, duty cycle 0.3, temperature 23 °C, and anode feed rate 0.5 mm/min.Furthermore, blisk blades have been successfully processed using these optimized parameters. | Chen Xuezhen Xu Zhengyang Zhu Dong Fang Zhongdong Zhu Di | 2016 | Chinese Journal of Aeronautics2016,29,1: | 17 |
| 7 | Agriculture Development-induced Surface Albedo Changes and Climatic Implications Across Northeastern China显示文摘To improve the understandings on regional climatic effects of past human-induced land cover changes,the surface albedo changes caused by conversions from natural vegetation to cropland were estimated across northeastern China over the last 300 years,and its climatic effects were simulated by using the Weather Research and Forecasting (WRF) model.Essential natural vegetation records compiled from historical documents and regional optimal surface albedo dataset were used.The results show that the surface albedo decreased by 0.01-0.03 due to conversions from grassland to cropland in the Northeast China Plain and it increased by 0.005-0.015 due to conversions from forests to cropland in the surrounding mountains.As a consequence,in the Northeast China Plain,the surface net radiation increased by 4-8 W/m 2,2-5 W/m 2,and 1-3 W/m 2,and the climate was therefore warmed by 0.1℃-0.2℃、0.1℃-0.2℃、 0.1℃-0.3 ℃ in the spring,autumn and winter,respectively.In the surrounding mountain area,the net radiation decreased by less than 1.5 W/m 2,and the climate was therefore cooled too slight to be detected.In summer,effects of surface albedo changes on climate were closely associated with moisture dynamics,such as evapotranspiration and cloud,instead of being merely determined by surface radiation budget.The simulated summer climatic effects have large uncertainties.These findings demonstrate that surface albedo changes resulted in warming climate effects in the non-rainy seasons in Northeast China Plain through surface radiation processes while the climatic effects in summer could hardly be concluded so far. | ZHANG Xuezhen WANG Wei-Chyung FANG Xiuqi YE Yu ZHENG Jingyun | 2012 | Chinese Geographical Science2012,22,3: | 15 |
| 8 | Evaluation of health benefit using Ben MAP-CE with an integrated scheme of model and monitor data during Guangzhou Asian Games显示文摘Guangzhou is the capital and largest city(land area:7287 km2)of Guangdong province in South China.The air quality in Guangzhou typically worsens in November due to unfavorable meteorological conditions for pollutant dispersion.During the Guangzhou Asian Games in November 2010,the Guangzhou government carried out a number of emission control measures that significantly improved the air quality.In this paper,we estimated the acute health outcome changes related to the air quality improvement during the 2010 Guangzhou Asian Games using a next-generation,fully-integrated assessment system for air quality and health benefits.This advanced system generates air quality data by fusing model and monitoring data instead of using monitoring data alone,which provides more reliable results.The air quality estimates retain the spatial distribution of model results while calibrating the value with observations.The results show that the mean PM_2.5concentration in November 2010 decreased by 3.5μg/m^3 compared to that in 2009 due to the emission control measures.From the analysis,we estimate that the air quality improvement avoided 106 premature deaths,1869 cases of hospital admission,and 20,026 cases of outpatient visits.The overall cost benefit of the improved air quality is estimated to be 165 million CNY,with the avoided premature death contributing 90%of this figure.The research demonstrates that Ben MAP-CE is capable of assessing the health and cost benefits of air pollution control for sound policy making. | Dian Ding Yun Zhu Carey Jang Che-Jen Lin Shuxiao Wang Joshua Fu Jian Gao Shuang Deng Junping Xie Xuezhen Qiu | 2016 | Journal of Environmental Sciences2016,28,4: | 13 |
| 9 | Schisandra sphenanthera extract(Wuzhi Tablet)protects against chronic-binge and acute alcohol-induced liver injury by regulating the NRF2-ARE pathway in mice显示文摘Alcohol abuse leads to alcoholic liver disease and no effective therapy is currently available.Wuzhi Tablet(WZ), a preparation of extract from Schisandra sphenanthera that is a traditional hepatoprotective herb, exerted a significant protective effect against acetaminophen-induced liver injury in our recent studies, but whether WZ can alleviate alcohol-induced toxicity remains unclear. This study aimed to investigate the contribution of WZ to alcohol-induced liver injury by using chronic-binge and acute models of alcohol feeding. The activities of ALT and AST in serum were assessed as well as the level of GSH and the activity of SOD in the liver. The expression of CYP2E1 and proteins in the NRF2-ARE signaling pathway including NRF2, GCLC, GCLM, HO-1 were measured, and the effect of WZ on NRF2 transcriptional activity was determined. We found that both models resulted in liver steatosis accompanied by increased transaminase activities, but that liver injury was significantly attenuated by WZ. WZ administration also inhibited CYP2E1 expression induced by alcohol, and elevated the level of GSH and the activity of SOD in the liver. Moreover, the NRF2-ARE signaling pathway was activated by WZ andthe target genes were all upregulated. Furthermore, WZ significantly activated NRF2 transcriptional activity. Collectively, our study demonstrates that WZ protected against alcohol-induced liver injury by reducing oxidative stress and improving antioxidant defense, possibly by activating the NRF2-ARE pathway. | Xuezhen Zeng Xi Li Chenshu Xu Fulin Jiang Yufei Mo Xiaomei Fan Yaoting Li Yiming Jiang Dongshun Li Min Huang Huichang Bi | 2017 | Acta Pharmaceutica Sinica B2017,7,5: | 13 |
| 10 | Mapping Heterotic Loci for Yield and Agronomic Traits Using Chromosome Segment Introgression Lines in Cotton显示文摘在现在的学习,一套染色体片断基因渗入排队(CSIL ) 使用 Gossypium hirsutum L。TM-1 作为接受者父母和 G。施主父母被用来为种间的混血儿探索杂种优势的基因基础的 barbadense Hai7124。个别地从与两个父母一起交叉的 CSIL 导出的 F1 人口的二个集合被设置调查 heterotic loci (HL ) 和替换效果 loci (SL ) 。58 HL 和 39 SL 的一个总数在 3 年里被识别。一稳定的 HL, hLP-A4-3,能在所有 3 年里被检测。三 HL, hBS-A8-1, hLP-D6-1,和 hSI-D7-11,能在 2 年里被检测。四 SL, sBS-D7-1, sLP-A8-1, sLP-D7-1,和 sLP-D12-1,能在 2 年里被检测。HL 和 SL 趋于在有靠近的位置的一些 HL 富有的染色体片断分布式。与在以前的研究检测的 QTL 相比, HL 与 QTL 显示出很少重叠,显示特点显型和杂种优势可能被 loci 的不同集合控制。基因效果的所有三种形式(部分 -- ,完整 -- ,在主导上) 被识别,当在主导上的效果做了主要贡献到杂种优势时。这些结果可以帮助为在棉花澄清杂种优势的遗传机制打了基础。 | Xian Guo Yuping Guo Jun Ma Fang Wang Mizhen Sun Lijuan Gui Jiajia Zhou Xianliang Song Xuezhen Sun Tianzhen Zhang | 2013 | Journal of Integrative Plant Biology2013,55,8: | 13 |
| 11 | Design and demonstration of a next-generation air quality attainment assessment system for PM_(2.5)and O_3显示文摘Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test—Community Edition(SMAT-CE) is developed for demonstrating attainment of air quality standards of O3 and PM2.5. SMAT-CE improves computational efficiency and provides a number of advanced visualization and analytical functionalities on an integrated GIS platform. SMAT-CE incorporates historical measurements of air quality parameters and simulated air pollutant concentrations under a number of emission inventory scenarios to project the level of compliance to air quality standards in a targeted future year. An application case study of the software based on the U.S. National Ambient Air Quality Standards(NAAQS) shows that SMAT-CE is capable of demonstrating the air quality attainment of annual PM2.5and 8-hour O3 for a proposed emission control policy. | Hua Wang Yun Zhu Carey Jang Che-Jen Lin Shuxiao Wang Joshua S.Fu Jian Gao Shuang Deng Junping Xie Dian Ding Xuezhen Qiu Shicheng Long | 2015 | Journal of Environmental Sciences2015,27,3: | 11 |
| 12 | A case study of development and application of a streamlined control and response modeling system for PM_(2.5)attainment assessment in China显示文摘This article describes the development and application of a streamlined air control and response modeling system with a novel response surface modeling-linear coupled fitting method and a new module to provide streamlined model data for PM_(2.5) attainment assessment in China.This method is capable of significantly reducing the dimensions required to establish a response surface model,as well as capturing more realistic response of PM_(2.5) to emission changes with a limited number of model simulations.The newly developed module establishes a data link between the system and the Software for Model Attainment Test—Community Edition(SMAT-CE),and has the ability to rapidly provide model responses to emission control scenarios for SMAT-CE using a simple interface.The performance of this streamlined system is demonstrated through a case study of the Yangtze River Delta(YRD) in China.Our results show that this system is capable of reproducing the Community Multi-Scale Air Quality(CMAQ) model simulation results with maximum mean normalized error < 3.5%.It is also demonstrated that primary emissions make a major contribution to ambient levels of PM_(2.5) in January and August(e.g.,more than50%contributed by primary emissions in Shanghai),and Shanghai needs to have regional emission control both locally and in its neighboring provinces to meet China's annual PM_(2.5)National Ambient Air Quality Standard.The streamlined system provides a real-time control/response assessment to identify the contributions of major emission sources to ambient PM_(2.5)(and potentially O_3 as well) and streamline air quality data for SMAT-CE to perform attainment assessments. | Shicheng Long Yun Zhu Carey Jang Che-Jen Lin Shuxiao Wang Bin Zhao Jian Gao Shuang Deng Junping Xie Xuezhen Qiu | 2016 | Journal of Environmental Sciences2016,28,3: | 9 |
| 13 | Reconstructing temperature change in Central East China during 601-920 AD显示文摘Using historical records on first and last frost and snow,spring cultivation,David peach blossom,autumn crop harvest,grade of sea freeze and change in northern citrus boundary,we reconstructed temperature change during 601-920 AD.The mean temperature of the winter half-year(October to April)over Central East China during this period was about-0.22°C higher than that of the present(1961-2000 AD mean).During 601-820 AD,mean temperature was about-0.52°C higher than the present.During 821-920 AD,the mean temperature was 0.42°C lower than the present.The temperature fluctuations were characterized by a maximum amplitude of 1.05°C at the centennial scale,1.38°C at the 50-year scale,2.02°C at the 30-year scale,and 2.3°C at the 20-year scale.There were four peaks warmer than today(601-620 AD,mean of 1°C higher temperature;641-660 AD,1.44°C;701-720 AD,0.88°C;781-800 AD,0.65°C).Three cold periods were in 741-760,821-840,and 881-900 AD,the mean temperature of which was 0.37-0.87°C lower than the present. | GE QuanSheng LIU HaoLong ZHENG JingYun ZHANG XueZhen | 2010 | Chinese Science Bulletin2010,55,34: | 8 |
| 14 | 1876-1878 severe drought in North China:Facts,impacts and climatic background显示文摘Based on the reconstructed precipitation series in North China from historical documents, the 1876-1878 drought was identified as the most severe and extreme one in North China over the past 300 years. Meanwhile, the spatial patterns of seasonal and annual precipitation during 1876-1877 were analyzed and the social and economic impacts related with this drought event were evaluated according to the descriptions in the historical documents. The results indicated that this long-lasting drought started by the spring of 1876 and did not stop until the spring of 1878. Within the three years, the harvest failures brought the rice price increased to 5-10 times than that in the normal year, and the total population in the five provinces over North China decreased by more than 20 million due to a large number of dead people and migrations. In addition, related investigations suggested that the 1876-1878 drought was prevalent worldwide, which has possible link with abnormal high SST in the equatorial central and eastern Pacific, strong El Nio episode and positive AAO anomalies. | HAO ZhiXin ZHENG JingYun WU GuoFeng ZHANG XueZhen GE QuanSheng | 2010 | Chinese Science Bulletin2010,55,26: | 8 |
| 15 | Carbon emissions induced by cropland expansion in Northeast China during the past 300 years显示文摘Assessments of the impacts of land use and land cover changes(LUCC) on the terrestrial carbon budget, atmospheric CO2 concentration, and CO2-related climatic change are important to understand the environmental effects of LUCC and provide information about the effects of historical carbon emissions. Using regional land cover reconstructions from historical records, with a bookkeeping model, we estimated the carbon sink changes caused by historical cropland expansion in Northeast China during the past 300 years. The conclusions are as follows:(1) There was a dramatic land reclamation of cropland during the past 300 years in Northeast China. Approximately 26% of the natural land was cultivated, and 38% of the grassland and 20% of the forest and shrubland were converted to cropland.(2) The carbon emission induced by cropland expansion between 1683 and 1980 was 1.06–2.55 Pg C, and the estimation from the moderate scenario was 1.45 Pg C. The carbon emissions of the soil carbon pool was larger than that from the vegetation carbon pool and comprised more than 2/3 of the total carbon emissions.(3) The carbon emissions of the three provinces in Northeast China were different. Heilongjiang Province had the largest carbon emissions, and Jilin Province had the second largest emissions.(4) The primary source of carbon emissions was forest reclamation(taking 60% of the total emissions in the moderate scenario), the secondary source was grassland cultivation(taking 27%), and the tertiary sources were shrubland and wetland reclamation(taking 13%). Examination on the data accuracy revealed that the high-resolution regional land cover data allowed the carbon budget to be evaluated at the county level and improved the precision of the results. The carbon emission estimation in this study was lower than those in previous studies because of the improved land use data quality and various types of land use change considered. | LI BeiBei FANG XiuQi YE Yu ZHANG XueZhen | 2014 | Science China Earth Sciences2014,57,9: | 8 |
| 16 | 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 |
| 17 | Reconstruction of cropland area and spatial distribution in the mid-Northern Song Dynasty (AD1004-1085)显示文摘为了理解历史的导致人的土地,盖住变化和它的气候的效果,与明确的空间信息创造历史的陆地使用数据集是必要的。用税农田区域和从历史的文件编的家庭的数字,我们在每陆(在北歌王朝的一个省级的政治区域) 以内估计了真实农田区域和人口在中间 -- 北歌王朝(AD1004-1085 ) 。评价通过分析税,人口和农业开发的当代的政策被完成。然后,我们把政治基于区域的农田区域变换成地理上明确的格子在由 60 km 的 60 km 的房间尺寸的基于房间的部分农田。变换作为独立变量用地志的斜坡,高度和人口密度基于每个格子房间的精明的耕作适用性。作为结果,在在 1070 年代的北歌领土以内的农田的全部的区域被估计是大约 7.2 亿亩(中国区域单位, 1 亩 = 666.7 m2 ) ,哪个 40.1% 和 59.9% 分别地发生在北方和南方。人口被估计是大约 8720 万,哪个 38.7% 和 61.3% 分别地在北方和南方,并且人均的农田区域是大约 8.2 亩。国家吝啬的开垦比率(即到全部的土地的农田区域的比率区域;RRA 此后为短) 是一回 16.6% 。平凡区域例如诺思中国平原,中间和长江的更低的活动范围, Guanzhong 平原,包围东廷·莱克和波伊昂·莱克和四川盆的平原,有更高的 RRA,主要是超过 40% ;当时多山、多山的区域例如 Nanling 山的南方,西南区域(排除 Chengdu 平原) ,黄土高原和东南沿海的区域,有更低的 RRA,是不到 20% 。而且, RRA 与地志的斜坡和高度变化了。在低高度(250 m ) 的区域,中间的高度(250100 m ) 和高高度(10003500 m ) ,有 4.43 亿, 2.15 亿并且 6400 万亩农田分别地并且他们的地区性的吝啬的 RRA 分别地是 27.5% , 12.6% 和 7.2% 。在扁平的斜坡,轻轻的斜坡,中等斜坡和陡峭的斜坡的区域,有 1.16 亿, 4.56 亿, 1.44 亿并且 200 万亩农田分别地并且他们的地区性的吝啬的 RRA 分别地是 34.6% , 20.7% , 8.5% 和 2.3% 。 | HE Fanneng LI Shicheng ZHANG Xuezhen | 2012 | Journal of Geographical Sciences2012,22,2: | 7 |
| 18 | DUXAP8, a pseudogene derived lncRNA, promotes growth of pancreatic carcinoma cells by epigenetically silencing CDKN1A and KLF2显示文摘Background:Recent studies highlight pseudogene derived long non-coding RNAs(lncRNAs)as key regulators of cancer biology.However,few of them have been well characterized in pancreatic cancer.Here,we aimed to identify the association between pseudogene derived lncRNA DUXAP8 and growth of pancreatic cancer cells.Methods:We screened for pseudogene derived lncRNAs associated with human pancreatic cancer by compara-tive analysis of three independent datasets from GEO.Quantitative real-time reverse transcription polymerase chain reaction was used to assess the relative expression of DUXAP8 in pancreatic cancer tissues and cells.Loss-of-function approaches were used to investigate the potential functional roles of DUXAP8 in pancreatic cancer cell proliferation and apoptosis in vitro and in vivo.RNA immunoprecipitation,chromosome immunoprecipitation assay and rescue experiments were performed to analyze the association of DUXAP8 with target proteins and genes in pancreatic cancer cells.Results:Pancreatic cancer tissues had significantly higher DUXAP8 levels than paired adjacent normal tissues.High DUXAP8 expression was associated with a larger tumor size,advanced pathological stage and shorter overall survival of pancreatic cancer patients.Moreover,silencing DUXAP8 expression by siRNA or shRNA inhibited pancreatic cancer cell proliferation and promoted apoptosis in vitro and in vivo.Mechanistic analyses indicated that DUXAP8 regulates PC cell proliferation partly through downregulation of tumor suppressor CDKN1A and KLF2 expression.Conclusion:Our results suggest that tumor expression of pseudogene derived lncRNA DUXAP8 plays an important role in pancreatic cancer progression.DUXAP8 may serve as a candidate biomarker and represent a novel therapeutic target of pancreatic cancer. | Yifan Lian Jiebin Yang Yikai Lian Chuangxing Xiao Xuezhen Hu Hongzhi Xu | 2018 | Cancer Communications2018,38,1: | 7 |
| 19 | A neurotrophic peptide-functionalized self-assembling peptide nanofiber hydrogel enhances rat sciatic nerve regeneration显示文摘神经指导水管(NGC ) 是为外部神经新生的自体同源的神经的一种潜在的选择。有希望的治疗学的策略是用物理或化学的指导暗示修改神经指导水管 intraluminal 微型环境。在这研究,神经营养的 peptide-functionalized 能在 vitro 支持 PC12 细胞粘附,增长,和 neuronal 区别的自我装配的肽 nanofiber hydrogel 是在一个空 chitosan 试管(hCST ) 的腔的 prefilled 在一只老鼠加速 axonal 新生臀部的神经缺点模型。functionalized 自我装配的肽被介绍神经营养的肽开发(RGI, RGIDKRHWNSQ ) 源于导出大脑的神经营养的因素(BDNF ) 到自我装配的肽 RADA16 的 C 终点 -- 我(交流 --(RADA )4-CONH2) 。词法,组织学, electrophysiological,和功能的分析证明 RGI-functionalized,自我装配,肽 nanofiber hydrogel RAD/RGI 能生产显著地与提高的 re-myelination 和马达改进了 axonal 新生的神经营养的微型环境功能的恢复。 | Jiaju Lu Xun Sun Heyong Yin Xuezhen Shen Shuhui Yang Yu Wang Wenli Jiang Yue Sun Lingyun Zhao Xiaodan Sun Shibi Lu Antonios G. Mikos Jiang Peng Xiumei Wang | 2018 | Nano Research2018,11,9: | 6 |
| 20 | Evolution of Microstructure,Mechanical Properties and Corrosion Resistance of Ultrasonic Assisted Welded-Brazed Mg/Ti Joint显示文摘Ultrasonic vibration with different powers from 0 k W to 1.6 k W was applied during the tungsten inert gas welding-brazing of Mg/Ti.The microstructures,mechanical properties and corrosion resistance of the ultrasonic assisted tungsten inert gas(U-TIG) welded-brazed Mg/Ti joint were characterized.The results showed that,without being subjected to ultrasonic vibration,coarse columnar α-Mg grains occurred in the fusion zone of Mg/Ti joint.However,with ultrasonic power of 1.2 k W,the average grain size of columnar α-Mg grains was refined from 200 μm to about 50 μm and the tensile strength of joints increased^18% up to 228 MPa.Besides,high fraction of grain boundaries was introduced by grain refinement,contributing to improve the corrosion resistance in two ways:(i) accelerating the formation of Mg(OH)2protective layer and(ii) reducing the mismatch and disorder between Mg(OH)2 protective layer and Mg alloy surface. | Chuan Xu Guangmin Sheng Xuezhen Cao Xinjian Yuan | 2016 | Journal of Materials Science & Technology2016,32,12: | 6 |