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1Evaluation of solar aided biomass power generation systems with parabolic trough field显示文摘Solar and biomass are both renewable energy resources.Using biomass as fuel is becoming more and more attractive after governments increase the tariff for the electricity from the renewable sources.However the costs of power from a biomass power generation plant depend greatly on the availability and quality of the biomass resource.The commercialization of solar alone thermal power generation is hindered by its high initial investment and low thermal efficiency.In this paper,a concept of integrating solar into a biomass power generation system is put forward.In the system the oil heated by a parabolic trough solar field is used to replace the extraction steam to preheat the feed water(entering a biomass boiler) and the previous extraction steam thus saved can continue to do work in the lower stages of turbine.The performance of the hybrid system with different replacements is analyzed and compared through two typical solar aided biomass generating units.The results show that the integration not only reduces the consumption of biomass fuel(at the same generation capacity) but is also proved to be an efficient way to convert solar thermal energy into power.The results also show that with the same solar aperture area,the higher the grade of the replaced extraction steam,the better the thermal performance and economy.HOU HongJuan YANG YongPing HU Eric SONG JiFeng DONG ChangQing MAO Jian 2011Science China(Technological Sciences)2011,54,6:15
2DNA image cytometry test for primary screening of esophageal cancer: a population-based multi-center study in high-risk areas in China显示文摘Objective: To evaluate the feasibility of DNA image cytometry(DNA-ICM) as a primary screening method for esophageal squamous cell cancer(ESCC).Methods: A total of 5,382 local residents aged 40–69 years from three high-risk areas in China(Linzhou in Henan province, Feicheng in Shandong province and Cixian in Hebei province) from 2008 to 2011 were recruited in this population-based screening study. And 2,526 subjects declined to receive endoscopic biopsy examination with Lugol's iodine staining, while 9 and 815 subjects were excluded from liquid-based cytology and DNA-ICM test respectively due to slide quality. Finally, 2,856, 5,373 and 4,567 subjects were enrolled in the analysis for endoscopic biopsy examination, liquid-based cytology and DNA-ICM test, respectively. Sensitivity(SE), specificity(SP), negative predictive values(NPV) and positive predictive values(PPV) as well as their 95% confidence intervals(95% CI) for DNA-ICM, liquid-based cytology and the combination of the two methods were calculated. Receiver operating characteristic(ROC) curves were applied to determine the cutoff point of DNA-ICM for esophageal cancer.Results: DNA-ICM results were significantly correlative with esophageal cancer and precancer lesions(χ~2=18.016, P<0.001). The cutoff points were 5,802, 5,803 and 8,002 based on dissimilar pathological types of low grade intraepithelial neoplasia(LGIN), high grade intraepithelial neoplasia(HGIN), and ESCC, respectively, and 5,803 was chosen in this study considering the SE and SP. The SE, SP, PPV, NPV of DNA-ICM test(cutoff point 5,803) combined with liquid-based cytology [threshold atypical squamous cells of undetermined significance(ASCUS)] were separately 72.1%(95% CI: 70.3%-73.9%), 43.3%(95% CI: 41.3%-45.3%), 22.8%(95% CI: 21.1%-24.5%) and 87.0%(95% CI: 85.7%-88.3%) for LGIN, 85.7%(95% CI: 84.3%-87.1%), 41.3%(95% CI: 39.3%-43.3%), 4.6%(95% CI: 3.8%-5.4%) and 98.9%(95% CI: 98.5%-99.3%) for HGIN, and 96.0%(95% CI: 95.2%-96.8%), 40.8%(95% CI: 38.8%-42.8%), 1.7%(95% CI: 1.2%-2.2%) and 99.9%(95% CI: 99.8%-100.0%) for ESCC.Conclusions: It is possible to use DNA-ICM test as a primary screening method before endoscopic screening for esophageal cancer.Meng Wang Changqing Hao Qing Ma Guohui Song Shanrui Ma Deli Zhao Lin Zhao Xinqing Li Wenqiang Wei 2016Chinese Journal of Cancer Research2016,28,4:15
3The impacts of conservation agriculture on crop yield in China depend on specific practices, crops and cropping regions显示文摘For smooth and wide application of conservation agriculture(CA), remaining uncertainties about its impacts on crop yield need to be reduced. Based on previous field experiments in China, a meta-analysis was performed to quantify the actual impacts of CA practices(NT: no/reduced-tillage only, CTSR: conventional tillage with straw retention, NTSR: NT with straw retention) on crop yields as compared to conventional tillage without straw retention(CT).Although CA practices increased crop yield by 4.6% on average, there were large variations in their impacts. For each CA practice, CTSR and NTSR significantly increased crop yield by 4.9%and 6.3%, respectively, compared to CT. However, no significant effect was found for NT. Among ecological areas, significant positive effects of CA practices were found in areas with an annual precipitation below 600 mm. Similar effects were found in areas with annual mean air temperature above 5 °C. For cropping regions, CA increased crop yield by 6.4% and 5.5%compared to CT in Northwest and South China, respectively, whereas no significant effects were found in the North China and Northeast China regions. Among crops, the positive effects of CA practices were significantly higher in maize(7.5%) and rice(4.1%) than in wheat(2.9%). NT likely decreased wheat yield. Our results indicate that there are great differences in the impacts of CA practices on crop yield, owing to regional variation in climate and crop types. CA will most likely increase maize yield but reduce wheat yield. It is strongly recommended to apply CA with crop straw retention in maize cropping areas and seasons with a warm and dry climate pattern.Chengyan Zheng Yu Jiang Changqing Chen Yanni Sun Jinfei Feng Aixing Deng Zhenwei Song Weijian Zhang 2014The Crop Journal2014,2,5:15
4Nat Microbiol:已结首次构建出小鼠肠道微生物组数据库显示文摘小鼠模型通常被广泛用于药理学和医学研究。我们都知道小鼠肠道中的微生物群落通常会对研究结果产生明显的影响,然而目前研究者们并没有获取到关于小鼠肠道中栖息细菌群落的详细信息。近日刊登在国际杂志Nature Microbiology上的一篇研究报告中。德国慕尼黑理工大学的研究者通过研究首次收集到了小鼠肠道中的多种细菌群落。同时研究者还对其进行了分裂、特性分析。最后得到了100种细菌,其中还包括15种迄今为止未知的细菌群落。Lu, Qiulun Yao, Yufeng Hu, Zhenkun Hu, Changqing Song, Qixue Ye, Jian Xu, Chengqi Wang, Annabel Z. Chen, Qiuyun Wang, Qing Kenneth 2016现代生物医学进展2016,16,32:13
5Cropland redistribution to marginal lands undermines environmental sustainability显示文摘Cropland redistribution to marginal land has been reported worldwide;however,the resulting impacts on environmental sustainability have not been investigated sufficiently.Here we investigated the environmental impacts of cropland redistribution in China.As a result of urbanization-induced loss of high-quality croplands in south China(~8.5 t ha^(-1)),croplands expanded to marginal lands in northeast(~4.5 t ha^(-1)) and northwest China(~2.9 t ha^(-1)) during 1990-2015 to pursue food security.However,the reclamation in these low-yield and ecologically vulnerable zones considerably undermined local environmental sustainability,for example increasing wind erosion(+3.47%),irrigation water consumption(+34.42%),fertilizer use(+20.02%) and decreasing natural habitats(-3.11%).Forecasts show that further reclamation in marginal lands per current policies would exacerbate environmental costs by 2050.The future cropland security risk will be remarkably intensified because of the conflict between food production and environmental sustainability.Our research suggests that globally emerging reclamation of marginal lands should be restricted and crop yield boost should be encouraged for both food security and environmental benefits.Wenhui Kuang Jiyuan Liu Hanqin Tian Hao Shi Jinwei Dong Changqing Song Xiaoyong Li Guoming Du Yali Hou Dengsheng Lu Wenfeng Chi Tao Pan Shuwen Zhang Rafiq Hamdi Zherui Yin Huimin Yan Changzhen Yan Shixin Wu Rendong Li Jiuchun Yang Yinyin Dou Wenbin Wu Liqiao Liang Bao Xiang Shiqi Yang 2022National Science Review2022,9,1:13
6Ecological-hydrological processes in arid environment: Past, present and future显示文摘Ecohydrology, aiming to study the interactions between terrestrial ecological systems and hydrological cycles as well as their impacts on water management, has been an emerging interdisciplinary research field since the 20 th century. It hosts both natural and human regulated processes that are potentially coupled in complex ways. Understanding the ecological-hydrological processes, the fundamental mechanisms and the connections between them is critical since these processes are not isolated but integrated to impact basin-scale hydrological and biogeochemical functioning of a larger river system, especially in arid environment where water resources are considered to be the source of life. Thus, research on ecological-hydrological processes in arid environment is not only a scientific focus area but also important to sustainable development. Research projects and initiatives involved in observation, measurement, modeling and data assimilation have been well-developed for those purposes over the past 20 years. This review summarizes the historical development of ecohydrology science in China and the state-of-the-art tools available in the research framework. Five grand scientific challenges are listed as prospects and exciting opportunities for the scientific community. To advance the current ecological-hydrological processes research, scientists from multidisciplinary backgrounds(such as geography, geology, geomorphology, hydrology, geochemistry and ecology), need to unite to tackle the many open problems in new dimensions.SONG Changqing YUAN Lihua YANG Xiaofan FU Bojie 2017Journal of Geographical Sciences2017,27,12:13
7A fundamental theorem for eco-environmental surface modelling and its applications显示文摘We propose a fundamental theorem for eco-environmental surface modelling(FTEEM) in order to apply it into the fields of ecology and environmental science more easily after the fundamental theorem for Earth’s surface system modeling(FTESM). The Beijing-Tianjin-Hebei(BTH) region is taken as a case area to conduct empirical studies of algorithms for spatial upscaling, spatial downscaling, spatial interpolation, data fusion and model-data assimilation, which are based on high accuracy surface modelling(HASM), corresponding with corollaries of FTEEM. The case studies demonstrate how eco-environmental surface modelling is substantially improved when both extrinsic and intrinsic information are used along with an appropriate method of HASM. Compared with classic algorithms, the HASM-based algorithm for spatial upscaling reduced the root-meansquare error of the BTH elevation surface by 9 m. The HASM-based algorithm for spatial downscaling reduced the relative error of future scenarios of annual mean temperature by 16%. The HASM-based algorithm for spatial interpolation reduced the relative error of change trend of annual mean precipitation by 0.2%. The HASM-based algorithm for data fusion reduced the relative error of change trend of annual mean temperature by 70%. The HASM-based algorithm for model-data assimilation reduced the relative error of carbon stocks by 40%. We propose five theoretical challenges and three application problems of HASM that need to be addressed to improve FTEEM.Tianxiang YUE Na ZHAO Yu LIU Yifu WANG Bin ZHANG Zhengping DU Zemeng FAN Wenjiao SHI Chuanfa CHEN Mingwei ZHAO Dunjiang SONG Shihai WANG Yinjun SONG Changqing YAN Qiquan LI Xiaofang SUN Lili ZHANG Yongzhong TIAN Wei WANG Ying’an WANG Shengnan MA Hongsheng HUANG Yimin LU Qing WANG Chenliang WANG Yuzhu WANG Ming LU Wei ZHOU Yi LIU Xiaozhe YIN Zong WANG Zhengyi BAO Miaomiao ZHAO Yapeng ZHAO Yimeng JIAO Ufra NASEER Bin FAN Saibo LI Yang YANG John PWILSON 2020Science China Earth Sciences2020,63,8:7
8Paleoenvironmental information recorded by pollen in B-3GC gravity core in Okinawa Trough显示文摘Based on pollen records in B-3GC gravity core, environmental change since 9500 aBP of Okinawa Trough and its adjacent islands was derived. The result showed that the most time during this period was in a warm temperate climate except in middle Holocene (6800-4400 aBP) that was under subtropical climate control. During 9500-8300 aBP and 3100-2000 aBP periods, it appeared colder and drier than the rest time. The original area of pollen sources surrounding Okinawa Trough was covered by evergreen and deciduous broadleaf forest alternatively with mixed broad-leaf-conifer forest distributed in high mountainous areas. Usually, these three kinds of forests existed at the same time with difference in altitude. Pollen from subtropical and tropical plants increased obviously in about 5000-6000 aBP, reflecting a great lifting of vegetation zone and expansion of evergreen broad-leaf forest in the study area. However, there was a slight descending of plant zone and shrinking of evergreen broadleaf forest duringSONG Changqing, SUN Xiangjun & Yoshiki SaitoNational Natural Science Foundation of China, Beijing 100085, China Open Lab of Marine Geology, Tongji University, Shanghai 200039, China Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China Geological Survey of Japan, Higashi 1-1-3, Tsukuba, Ibaraki, 305-8567,Japan 2001Chinese Science Bulletin2001,46,11:7
9Additive manufacturing of CNTs/PLA composites and the correlation between microstructure and functional properties显示文摘Owing to the facile,low cost,rapid,personalization characters,3D printing method has been one of the most attractive additive manufacturing processes in medicine,airplane,packaging and printing areas.In this work,a series of carbon nanotubes/polylactic acid(CNTs/PLA) composites were prepared through the combination of molten co-extrusion and 3D printing processes.The orientation and dispersion of CNTs in PLA matrix were investigated to explore the impact of 3D printing process on the morphology of CNTs/PLA composites via transmission electron microscopy,field emission scanning electron microscopy and Raman spectroscopy.X-ray diffractometer,differential scanning calorimetry,and thermal gravity analysis were employed to study the crystal structure and thermal properties of the composites.In addition,the electrical conductivity of the prepared specimen revealed that the orientation of CNTs in PLA might enhance the conductivity of the composite.It was found that 3D printing process was beneficial to increasing the purity of CNTs,electrical conductivity and mechanical properties of CNTs/PLA composites.Xing Zhou Jingrui Deng Changqing Fang Wanqing Lei Yonghua Song Zisen Zhang Zhigang Huang Yan Li 2021Journal of Materials Science & Technology2021,,1:6
10Preparation and Characterization of Waterborne Polyurethane/Cellulose Nanocrystal Composite Membrane from Recycling Waste Paper显示文摘Cellulose plays a key role in abundant organic natural materials meeting the increasing demand for green and biocompatible products.The highly crystalline nanoscale component of cellulose nanocrystals has recently attracted great attention due to the versatile performance as filler or matrix in producing functional materials.In this work,we prepared the waterborne polyurethane via a prepolymer process,and obtained cellulose and cellulose nanocrystals from waste paper via a facile acid hydrolysis process.After that,the cellulose nanocrystals were assembled into film and mixed with polyurethane to prepare flexible polyurethane/cellulose nanocrystals composite membrane with different soaking time.The correlation between the bulk structure and applied properties including thermal resistance and mechanical property was investigated by using Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),thermogravimetric analysis(TGA),differential scanning calorimetry(DSC)and folding test.The structure analysis indicates that cellulose nanocrystals prepared from used paper have a quality similar to that of commercial cellulose.Meanwhile,the cellulose nanocrystals have been mixed with polyurethane uniformly.Polyurethane can significantly benefit to the thermal resistance and mechanical property of the cellulose nanocrystals film.The polyurethane/cellulose nanocrystals composite membrane present good flexibility and may hold a significantly potential application as visual and flexible material.Xing Zhou Xin Zhang Dong Wang Changqing Fang Wanqing Lei Zhigang Huang Yonghua Song Xinyu He Yingwei Huang 2020Journal of Renewable Materials2020,8,6:5
11Anatomical variation of infra-pyloric artery origination: A prospective multicenter observational study (IPA-Origin)显示文摘Objective: Infra-pyloric artery(IPA) is an important anatomical landmark in treatment of gastric cancer and is the key vessel for pylorus-preserving gastrectomy and subgroup of infra-pyloric lymph nodes. However, its anatomical variation is not thoroughly understood. Our study aimed to clarify the origination of the IPA.Methods: We did this prospective, multicenter, open-label, observational study at gastric surgery departments of34 hospitals in China. Gastric cancer patients aged 18 years or older and scheduled to undergo elective total or distal gastrectomy were assigned. During the surgery, IPA dissecting and exposing the origination point with photographs or video clips were required. The primary outcome was the origination of the IPA. Analysis of variance, χ~2 tests and Fisher's tests were used to analyze the differences between groups. The study is registered at Clinicaltrials.gov(No. NCT03071237).Results: Between May 8 and July 31, 2017, 429 patients were assigned for the study, and 419(97.7%) patients had the IPA dissected and recorded through photograph or video and were included in the primary outcome analysis. The median age was 62 years old, and 73.7% were male. Among the patients, 78.5% received laparoscopic surgery. Single IPA origination was identified in 398(95.0%) patients, including gastroduodenal artery(GDA) in154(36.8%) patients, anterior superior pancreaticoduodenal artery(ASPDA) in 130(31.0%) patients, and right gastroepiploic artery(RGEA) in 114(27.2%) patients. Fifteen(3.6%) patients were identified with multiple IPA and 6(1.4%) patients were identified as IPA absence. The differences in the distribution of surgical approach(P=0.003) and geographic area(P=0.030) were statistically significant. No difference was shown in sex, age,gastrectomy type, tumor location, and clinical T, N and M stage.Conclusions: Our study found that the IPA originates from GDA, ASPDA and RGEA in similar proportions.Laparoscopic surgery may be more helpful in dissection of the IPA than open surgery.Rulin Miao Jianjun Qu Zhengrong Li Daguang Wang Jiang Yu Weidong Zang Yong Li Fenglin Liu Jian Zhang Wu Song Kai Ye Su Yan Wei Wang Shuangyi Ren Lu Zang Changqing Jing Li Zhang Kuan Wang Weihua Fu Lin Fan Bin Liang Gang Zhao Jun Cai Li Yang Jiaming Zhu Jun You Kun Yang Qingxing Huang Zhaojian Niu Ning Ning Xingfeng Qiu Gang Ji Feng Liang Hua Huang Chao Gao Fei Shan Shuangxi Li Yongning Jia Lianhai Zhang Xiangji Ying Yan Zhang Zhaode Bu Xiangqian Su Gang Zhao Ziyu Li Jiafu Ji 2018Chinese Journal of Cancer Research2018,30,5:5
12Whole Genome Analyses of Chinese Population and De Novo Assembly of A Northern Han Genome显示文摘To unravel the genetic mechanisms of disease and physiological traits,it requires comprehensive sequencing analysis of large sample size in Chinese populations.Here,we report the primary results of the Chinese Academy of Sciences Precision Medicine Initiative(CASPMI)project launched by the Chinese Academy of Sciences,including the de novo assembly of a northern Han reference genome(NH1.0)and whole genome analyses of 597 healthy people coming from most areas in China.Given the two existing reference genomes for Han Chinese(YH and HX1)were both from the south,we constructed NH1.0,a new reference genome from a northern individual,by combining the sequencing strategies of PacBio,10×Genomics,and Bionano mapping.Using this integrated approach,we obtained an N50 scaffold size of 46.63 Mb for the NH1.0 genome and performed a comparative genome analysis of NH1.0 with YH and HX1.In order to generate a genomic variation map of Chinese populations,we performed the whole-genome sequencing of 597 participants and identified 24.85 million(M)single nucleotide variants(SNVs),3.85 M small indels,and 106,382 structural variations.In the association analysis with collected phenotypes,we found that the T allele of rs1549293 in KAT8 significantly correlated with the waist circumference in northern Han males.Moreover,significant genetic diversity in MTHFR,TCN2,FADS1,and FADS2,which associate with circulating folate,vitamin B12,or lipid metabolism,was observed between northerners and southerners.Especially,for the homocysteine-increasing allele of rs1801133(MTHFR 677T),we hypothesize that there exists a “comfort”zone for a high frequency of 677T between latitudes of 35–45 degree North.Taken together,our results provide a high-quality northern Han reference genome and novel population-specific data sets of genetic variants for use in the personalized and precision medicine.Zhenglin Du Liang Ma Hongzhu Qu Wei Chen Bing Zhang Xi Lu Weibo Zhai Xin Sheng Yongqiao Sun Wenjie Li Meng Lei Qiuhui Qi Na Yuan Shuo Shi Jingyao Zeng Jinyue Wang Yadong Yang Qi Liu Yaqiang Hong Lili Dong Zhewen Zhang Dong Zou Yanqing Wang Shuhui Song Fan Liu Xiangdong Fang Hua Chen Xin Liu Jingfa Xiao Changqing Zeng 2019Genomics, Proteomics & Bioinformatics2019,17,3:4
13A Facile Self-assembly Synthesis of Hexagonal ZnO Nanosheet Films and Their Photoelectrochemical Properties显示文摘Here, large-scale and uniform hexagonal zinc oxide(ZnO) nanosheet films were deposited onto indium tin oxide(ITO)-coated transparent conducting glass substrates via a facile galvanic displacement deposition process. Compared with other commonly used solution methods, this process avoids high temperature and electric power as well as supporting agents to make it simple and cost-effective. The as-fabricated ZnO nanosheet films have uniform hexagonal wurtzite structure. The photoelectrochemical(PEC) cell based on ZnO nanosheet film/ITO photoelectrode was also fabricated and its performance was improved by optimizing the solution concentration. A higher photocurrent density of*500 l A cm^(-2)under AM 1.5 G simulated illumination of 100 m W cm^(-2)with zero bias potential(vs. Ag/AgCl electrode) was obtained, which may ascribe to the increased surface-to-volume ratio of disordered Zn O nanosheet arrays. Our developed method may be used to deposit other oxide semiconductors, and the Zn O nanosheet film/ITO PEC cell can be used to design low-cost optoelectronic and photoelectrochemical devices.Bin Zhang Faze Wang Changqing Zhu Qiang Li Jingnan Song Maojun Zheng Li Ma Wenzhong Shen 2016Nano-Micro Letters2016,8,2:3
14Impact of Droughts on Winter Wheat Yield in Different Growth Stages during 2001–2016 in Eastern China显示文摘Remote sensing can provide near real-time and dynamic monitoring of drought. The drought severity index(DSI), based on the normalized difference vegetation index(NDVI) and evapotranspiration/potential evapotranspiration(ET/PET), has been used for drought monitoring. This study examined the relationship between the DSI and winter wheat yield for prefecture-level cities in five provinces of eastern China during 2001–2016. We first analyzed the spatial and temporal distribution of droughts in the study area. Then the correlation coefficient between drought-affected area and detrended yield of winter wheat was quantified and the impact of droughts of different intensities on winter wheat yield during different growth stages was investigated. The results show that incipient drought during the wintering period has no significant impact on the yield of winter wheat, while moderate drought in the same period can reduce yield. Drought affects winter wheat yield significantly during the flowering and filling stages. Droughts of higher intensity have more significant negative effects on the yield of winter wheat. Monitoring of droughts and irrigation is critical during these periods to ensure normal yield of winter wheat. This study has important practical implications for the planning of irrigation and food security.Huiqian Yu Qiang Zhang Peng Sun Changqing Song 2018International Journal of Disaster Risk Science2018,9,3:3
15Room temperature ferromagnetism of Ni, (Ni, Li), (Ni, N)-doped ZnO thin films显示文摘Ni-doped ZnO thin films (Ni concentration up to 10 mol%) were generated on Si (100) substrates by a sol-gel technique. The films showed wurtzite structure and no other phase was found. The chemical state of Ni was found to be bivalent by X-ray photoelectron spectroscopy. The results of magnetic measurements at room temperature indicated that the films were ferromagnetic, and magnetic moment decreased with rise of Ni concentration. The magnetization of Ni (10 mol%)-doped ZnO film annealed in nitrogen was lower than that annealed in argon, suggesting that the density of defects had an effect on ferromagnetism.YE XiaoJuan SONG HaiAn ZHONG Wei QI XiaoSi XU MeiHua JIN ChangQing YANG ZaiXin AU ChakTong DU YouWei 2010中国科学:技术科学2010,40,2:2
16Exploring detailed urban-rural development under intersecting population growth and food production scenarios: Trajectories for China’s most populous agricultural province to 2030显示文摘Henan,China,is likely the most populous agricultural province worldwide.It is China’s major grain-producing area,with a continuously increasing population(96 million),which is greater than 93%of countries worldwide.However,this province has been experiencing unprecedented urbanization recently due to national policies and measures,such as a plan to build the capital city of Henan into a national center,resulting in severe conflicts in land use that endanger food security regionally and globally.To facilitate decision-making on this problem,we explored the detailed urban-rural development of Henan by modeling these land-use conflicts.Conventional modeling of a region’s urban-rural development is to navigate trade-offs(a)solely between different land-use types(b)by assuming that each type provides a single service(e.g.,croplands produce all the food),and(c)under a polynomial regression-based projection of population.In contrast,we considered both land-use type and intensity,resulting in a detailed land system for Henan.By introducing the concept of land system services(e.g.,food production),we established a many-to-many relationship between land system classes and services.These allowed us to carry out the most comprehensive modeling of Henan’s urban-rural development under eighteen combined scenarios of population growth and land-use policies on food production.The modeling results of these scenarios provide a solid basis for making decisions regarding Henan’s urban-rural development.We also revealed the influence mechanism of population growth,land-use policies,and their combinations,highlighting the benefits of securing food production by agricultural intensification rather than merely expanding the area of cropland.GAO Peichao XIE Yiru SONG Changqing CHENG Changxiu YE Sijing 2023Journal of Geographical Sciences2023,33,2:2
17Antigen-non-specific regulation centered on CD25^(+)Foxp3^(+) Treg cells显示文摘CD25^(+)Foxp3^(+) regulatory T cells(Tregs)are of special interest in immunology because of their potent inhibitory function.Many fundamental aspects of Tregs,including their antigenic profile,development and peripheral homeostasis,remain highly controversial.Here,we propose a Treg-centered antigen-non-specific immunoregulation model focused on the T-cell system,particularly on CD41 T cells.The T-cell pool consists of naive T cells(Tnais),Tregs and effector T cells(Teffs).Regardless of antigen specificity,the ratio of the activated T-cell subsets(Treg/Teff/Tnai)and their temporal and spatial uniformity dictate the differentiation of Tnais.Activated Tregs inhibit the activation,proliferation,induction and activity of Teffs;in contrast,activated Teffs inhibit the induction of Tregs from Tnais but cooperate with Treg-specific antigens to promote the proliferation and activity of Tregs.In many cases,these interactions are antigen-non-specific,whereas the activation of both Tregs and Teffs is antigen-specific.Memory T-cell subsets are essential for the maintenance of adaptive immune responses,but the antigen-non-specific interactions among T-cell subsets may be more important during the establishment of the adaptive immune system to a newly encountered antigen.This is especially important when new and memory antigens are presented closely—both temporally and spatially—to T cells,because there are always baseline levels of activated Tregs,which are usually higher than levels of memory T cells for new antigens.Based on this hypothesis,we further infer that,under physiological conditions,Tregs in lymph nodes mainly recognize antigens frequently released from draining tissues,and that these self-reactive Tregs are commonly involved in the establishment of adaptive immunity to new antigens and in the feedback control of excessive responses to pathogens.Gangzheng Hu Zhongmin Liu Changqing Zheng Song Guo Zheng 2010Cellular & Molecular Immunology2010,7,6:2
18Spatial-temporal Distribution Characteristics of Global Seismic Clusters and Associated Spatial Factors显示文摘Earthquakes exhibit clear clustering on the earth. It is important to explore the spatial-temporal characteristics of seismicity clusters and their spatial heterogeneity. We analyze effects of plate space, tectonic style, and their interaction on characteristic of cluster.Based on data of earthquakes not less than moment magnitude(M_w) 5.6 from 1960 to 2014, this study used the spatial-temporal scan method to identify earthquake clusters. The results indicate that seismic spatial-temporal clusters can be classified into two types based on duration: persistent clusters and burst clusters. Finally, we analysed the spatial heterogeneity of the two types. The main conclusions are as follows: 1) Ninety percent of the persistent clusters last for 22-38 yr and show a high clustering likelihood;ninety percent of the burst clusters last for 1-1.78 yr and show a high relative risk. 2) The persistent clusters are mainly distributed in interplate zones, especially along the western margin of the Pacific Ocean. The burst clusters are distributed in both intraplate and interplate zones, slightly concentrated in the India-Eurasia interaction zone. 3) For the persistent type, plate interaction plays an important role in the distribution of the clusters’ likelihood and relative risk. In addition, the tectonic style further enhances the spatial heterogeneity. 4) For the burst type,neither plate activity nor tectonic style has an obvious effect on the distribution of the clusters’ likelihood and relative risk. Nevertheless,interaction between these two spatial factors enhances the spatial heterogeneity, especially in terms of relative risk.YANG Jing CHENG Changxiu SONG Changqing SHEN Shi ZHANG Ting NING Lixin 2019Chinese Geographical Science2019,29,4:2
19Cross-national Perspectives on Using Sustainable Development Goals(SDGs) Indicators for Monitoring Sustainable Development: A Database and Analysis显示文摘Sustainable development is the theme of the 21st century. To monitor the progress of sustainable development, the United Nations launched Sustainable Development Goals(SDGs) in 2015. Subsequently, nations of the world have drawn up a list of localized indicators regarding the United Nations SDGs as a paradigm. We established a database including SDGs indicator systems of 11 economies by collecting and determining a large number of materials. Based on this database, we analyzed SDGs indicators by designing a conceptual framework of comparative analysis that included three views. We found that the SDGs indicator systems of 11 economies are different between the number of indicators, the proportion of different categories, and the connotation of indicators. Although the SDGs indicator systems among economies regarded the United Nations SDGs as a framework and included the major social problems related to sustainability, the inconsistency between SDGs indicator systems is large. It is a major reason why scholars lack the systematic method for developing indicators. There are challenges faced in data accessibility. The framework for comparative analysis could be applied to different economies.WANG Xiangyu SONG Changqing CHENG Changxiu YE Sijing SHEN Shi 2021Chinese Geographical Science2021,31,4:2
20The C_(6)D_(6)detector system on the Back-n beam line of CSNS显示文摘Introduction The neutron capture cross sections are very important in the field of nuclear device design and basic physics research.Hydrogen-free liquid scintillator such as C_(6)D_(6)detectors are widely used in the neutron capture cross-sectional measurements for the low neutron sensitivity and fast time response.The Back-n white neutron source at China Spallation Neutron Source is the first spallation white neutron source in China,and it is suitable for neutron capture cross-sectional measurement.Materials and methods A C_(6)D_(6)detector system was built in the Back-n experimental station.The pulse height weighting technique was used to determine the system’s detection efficiency.The response to gamma rays of the C_(6)D_(6)detector was measured,and the energy resolution function was determined.Monte Carlo simulation with Geant4 code was carried out to get the weighting function of this C_(6)D_(6)detector system.Additionally,the systematic uncertainty of the weighting function was also determined.Conclusion According to the experimental and simulation results,this C_(6)D_(6)detector system can be used to measure neutron capture cross section.Jie Ren Xichao Ruan Jie Bao Guangyuan Luan Wei Jiang Qi An Huaiyong Bai Ping Cao Qiping Chen Yonghao Chen Pinjing Cheng Zengqi Cui Ruirui Fan Changqing Feng Minhao Gu Fengqin Guo Changcai Han Zijie Han Guozhu He Yongcheng He Yuefeng He Hanxiong Huang Weiling Huang Xiru Huang Xiaolu Ji Xuyang Ji Haoyu Jiang Hantao Jing Ling Kang Mingtao Kang Bo Li Lun Li Qiang Li Xiao Li Yang Li Yang Li Rong Liu Shubin Liu Xingyan Liu Yinglin Ma Changjun Ning Binbin Qi Zhaohui Song Hong Sun Xiaoyang Sun Zhijia Sun Zhixin Tan Hongqing Tang Jingyu Tang Pengcheng Wang Qi Wang Taofeng Wang Yanfeng Wang Zhaohui Wang Zheng Wang Jie Wen Zhongwei Wen Qingbiao Wu Xiaoguang Wu Xuan Wu Likun Xie Yiwei Yang Han Yi Li Yu Tao Yu Yongji Yu Guohui Zhang Jing Zhang Linhao Zhang Liying Zhang Qingmin Zhang Qiwei Zhang Xianpeng Zhang Yuliang Zhang Zhiyong Zhang Yingtan Zhao Liang Zhou Zuying Zhou Danyang Zhu Kejun Zhu Peng Zhu 2019Radiation Detection Technology and Methods2019,3,3:1
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