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191篇 您的检索式:作者名="Di Tian"
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1Current pattern of Chinese dialysis units: a cohort study in a representative sample of units显示文摘ZHOU Qiu-gen JIANG Jian-ping WU Sheng-jie TIAN Jian-wei CHEN Jiang-hua YU Xue-qing CHEN Ping-yan MEI Chang-lin XIONG Fei SHI Wei ZHOU Wei LIU Xu-sheng SUN Shi-ren XIE Di LIU Jun XU Xin HOU Fan-fan 2012Chinese Medical Journal2012,,19:69
2Persistence and clearance of viral RNA in 2019 novel coronavirus disease rehabilitation patients显示文摘Background:A patient’s infectivity is determined by the presence of the virus in different body fluids,secretions,and excreta.The persistence and clearance of viral RNA from different specimens of patients with 2019 novel coronavirus disease(COVID-19)remain unclear.This study analyzed the clearance time and factors influencing 2019 novel coronavirus(2019-nCoV)RNA in different samples from patients with COVID-19,providing further evidence to improve the management of patients during convalescence.Methods:The clinical data and laboratory test results of convalescent patients with COVID-19 who were admitted to from January 20,2020 to February 10,2020 were collected retrospectively.The reverse transcription polymerase chain reaction(RT-PCR)results for patients’oropharyngeal swab,stool,urine,and serum samples were collected and analyzed.Convalescent patients refer to recovered non-febrile patients without respiratory symptoms who had two successive(minimum 24 h sampling interval)negative RT-PCR results for viral RNA from oropharyngeal swabs.The effects of cluster of differentiation 4(CD4)+T lymphocytes,inflammatory indicators,and glucocorticoid treatment on viral nucleic acid clearance were analyzed.Results:In the 292 confirmed cases,66 patients recovered after treatment and were included in our study.In total,28(42.4%)women and 38 men(57.6%)with a median age of 44.0(34.0-62.0)years were analyzed.After in-hospital treatment,patients’inflammatory indicators decreased with improved clinical condition.The median time from the onset of symptoms to first negative RT-PCR results for oropharyngeal swabs in convalescent patients was 9.5(6.0-11.0)days.By February 10,2020,11 convalescent patients(16.7%)still tested positive for viral RNA from stool specimens and the other 55 patients’stool specimens were negative for 2019-nCoV following a median duration of 11.0(9.0-16.0)days after symptom onset.Among these 55 patients,43 had a longer duration until stool specimens were negative for viral RNA than for throat swabs,with a median delay of 2.0(1.0-4.0)days.Results for only four(6.9%)urine samples were positive for viral nucleic acid out of 58 cases;viral RNA was still present in three patients’urine specimens after throat swabs were negative.Using a multiple linear regression model(F=2.669,P=0.044,and adjusted R2=0.122),the analysis showed that the CD4+T lymphocyte count may help predict the duration of viral RNA detection in patients’stools(t=-2.699,P=0.010).The duration of viral RNA detection from oropharyngeal swabs and fecal samples in the glucocorticoid treatment group was longer than that in the non-glucocorticoid treatment group(15 days vs.8.0 days,respectively;t=2.550,P=0.013)and the duration of viral RNA detection in fecal samples in the glucocorticoid treatment group was longer than that in the non-glucocorticoid treatment group(20 days vs.11 days,respectively;t=4.631,P<0.001).There was no statistically significant difference in inflammatory indicators between patients with positive fecal viral RNA test results and those with negative results(P>0.05).Conclusions:In brief,as the clearance of viral RNA in patients’stools was delayed compared to that in oropharyngeal swabs,it is important to identify viral RNA in feces during convalescence.Because of the delayed clearance of viral RNA in the glucocorticoid treatment group,glucocorticoids are not recommended in the treatment of COVID-19,especially for mild disease.The duration of RNA detection may relate to host cell immunity.Yun Ling Shui-Bao Xu Yi-Xiao Lin Di Tian Zhao-Qin Zhu Fa-Hui Dai Fan Wu Zhi-Gang Song Wei Huang Jun Chen Bi-Jie Hu Sheng Wang En-Qiang Mao Lei Zhu Wen-Hong Zhang Hong-Zhou Lu 2020Chinese Medical Journal2020,,9:58
3Global leaf nitrogen and phosphorus stoichiometry and their scaling exponent显示文摘Leaf nitrogen(N) and phosphorus(P) concentrations constrain photosynthetic and metabolic processes,growth and the productivity of plants. Their stoichiometry and scaling relationships regulate the allocation of N and P from subcellular to organism, and even ecosystem levels, and are crucial to the modelling of plant growth and nutrient cycles in terrestrial ecosystems. Prior work has revealed a general biogeographic pattern of leaf N and P stoichiometric relationships and shown that leaf N scales roughly as two-thirds the power of P. However, determining whether and how leaf N and P stoichiometries, especially their scaling exponents, change with functional groups and environmental conditions requires further verification. In this study, we compiled a global data set and documented the global leaf N and P concentrations and the N:P ratios by functional group, climate zone and continent. The global overall mean leaf N and P concentrations were 18.9 mg g^(-1) and 1.2 mg g^(-1), respectively, with significantly higher concentrations in herbaceous than woody plants(21.72 mg g^(-1) vs. 18.22 mg g^(-1) for N; and 1.64 mg g^(-1) vs. 1.10 mg g^(-1) for P). Both leaf N and P showed higher concentrations at high latitudes than low latitudes. Among six continents, Europe had the highest N and P concentrations(20.79 and 1.54 mg g^(-1)) and Oceania had the smallest values(10.01 and 0.46 mg g^(-1)). These numerical values may be used as a basis for the comparison of other individual studies. Further, we found that the scaling exponent varied significantly across different functional groups,latitudinal zones, ecoregions and sites. The exponents of herbaceous and woody plants were 0.659 and0.705, respectively, with significant latitudinal patterns decreasing from tropical to temperate to boreal zones. At sites with a sample size ≥10, the values fluctuated from 0.366 to 1.928, with an average of 0.841.Several factors including the intrinsic attributes of different life forms, P-related growth rates and relative nutrient availability of soils likely account for the inconstant exponents of leaf N vs. P scaling relationships.Di Tian Zhengbing Yan Karl J.Niklas Wenxuan Han Jens Kattge Peter B.Reich Yongkai Luo Yahan Chen Zhiyao Tang Huifeng Hu Ian J.Wright Bernhard Schmid Jingyun Fang 2018National Science Review2018,5,5:24
4Individualized prediction of perineural invasion in colorectal cancer: development and validation of a radiomics prediction model显示文摘Objective: To develop and validate a radiomics prediction model for individualized prediction of perineural invasion(PNI) in colorectal cancer(CRC).Methods: After computed tomography(CT) radiomics features extraction, a radiomics signature was constructed in derivation cohort(346 CRC patients). A prediction model was developed to integrate the radiomics signature and clinical candidate predictors [age, sex, tumor location, and carcinoembryonic antigen(CEA) level]. Apparent prediction performance was assessed. After internal validation, independent temporal validation(separate from the cohort used to build the model) was then conducted in 217 CRC patients. The final model was converted to an easy-to-use nomogram.Results: The developed radiomics nomogram that integrated the radiomics signature and CEA level showed good calibration and discrimination performance [Harrell's concordance index(c-index): 0.817; 95% confidence interval(95% CI): 0.811–0.823]. Application of the nomogram in validation cohort gave a comparable calibration and discrimination(c-index: 0.803; 95% CI: 0.794–0.812).Conclusions: Integrating the radiomics signature and CEA level into a radiomics prediction model enables easy and effective risk assessment of PNI in CRC. This stratification of patients according to their PNI status may provide a basis for individualized auxiliary treatment.Yanqi Huang Lan He Di Dong Caiyun Yang Cuishan Liang Xin Chen Zelan Ma Xiaomei Huang Su Yao Changhong Liang Jie Tian Zaiyi Liu 2018Chinese Journal of Cancer Research2018,30,1:23
5Future Changes and Uncertainties in Temperature and Precipitation over China Based on CMIP5 Models显示文摘Climate changes in future 21 st century China and their uncertainties are evaluated based on 22 climate models from the Coupled Model Intercomparison Project Phase 5(CMIP5). By 2081–2100, the annual mean surface air temperature(SAT) is predicted to increase by 1.3℃± 0.7℃, 2.6℃± 0.8℃ and 5.2℃± 1.2℃ under the Representative Concentration Pathway(RCP) scenarios RCP2.6, RCP4.5 and RCP8.5, relative to 1986–2005, respectively. The future change in SAT averaged over China increases the most in autumn/winter and the least in spring, while the uncertainty shows little seasonal variation.Spatially, the annual and seasonal mean SAT both show a homogeneous warming pattern across China, with a warming rate increasing from southeastern China to the Tibetan Plateau and northern China, invariant with time and emissions scenario.The associated uncertainty in SAT decreases from northern to southern China. Meanwhile, by 2081–2100, the annual mean precipitation increases by 5% ± 5%, 8% ± 6% and 12% ± 8% under RCP2.6, RCP4.5 and RCP8.5, respectively. The national average precipitation anomaly percentage, largest in spring and smallest in winter, and its uncertainty, largest in winter and smallest in autumn, show visible seasonal variations. Although at a low confidence level, a homogeneous wetting pattern is projected across China on the annual mean scale, with a larger increasing percentage in northern China and a weak drying in southern China in the early 21 st century. The associated uncertainty is also generally larger in northern China and smaller in southwestern China. In addition, both SAT and precipitation usually show larger seasonal variability on the sub-regional scale compared with the national average.TIAN Di GUO Yan DONG Wenjie 2015Advances in Atmospheric Sciences2015,32,4:21
6Changes in China’s lakes: climate and human impacts显示文摘Lakes have played a critical role in providing water and ecosystem services for people and other organisms in China for millennia.However,accelerating climate change and economic boom have resulted in unprecedented changes in these valuable lakes.Using Landsat images covering the entity of the country,we explored the changes in China’s lakes and the associated driving forces over the last 30 years(i.e.mid-1980 s to 2015).We discovered that China’s lakes have changed with divergent regional trends:in the sparsely populated Tibetan Plateau,lakes are abundant and the lake area has increased dramatically from 38596 to46831 km^2(i.e.increased by 8235 km^2,or 21.3%),whereas,in the densely populated northern and eastern regions,lakes are relatively scarce and the lake area has decreased from 36659 to 33657 km^2(i.e.decreased by 3002 km^2,or 8.2%).In particular,severe lake decreases occurred in the Mongolia-Xinjiang Plateau and the Eastern Plain(-2151 km^2).Statistical analyses indicated that climate was the most important factor controlling lake changes in the Tibetan Plateau,the Yun-Gui Plateau and the Northeast Plain.However,the strength of climatic control on lake changes was low in the Eastern Plain and the Mongolia-Xinjiang Plateau,where human activities,e.g.impoldering,irrigation and mining,have caused serious impacts on lakes.Further lake changes will exacerbate regional imbalances between lake resources and population distribution,and thus may increase the risk of water-resource crises in China.Shengli Tao Jingyun Fang Suhui Ma Qiong Cai Xinyu Xiong Di Tian Xia Zhao Leqi Fang Heng Zhang Jiangling Zhu Shuqing Zhao 2020National Science Review2020,7,1:14
7Extracting mineral alteration information using WorldView-3 data显示文摘The multispectral commercial satellite-WorldView-3(WV-3) has the highest spatial, spectral and radiation resolutions among the satellites currently and can generate good data in the shortwave infrared(SWIR). The study area is located in the Pobei area of Xinjiang Uygur Autonomous Region, which is rich in mineral resources. The spectral analyses of some typical altered hydroxy-bearing, iron-bearing, and carbonate-bearing minerals could establish several Principal Component Analysis(PCA) models and mineral indices, using the visible and near infrared(VNIR) and the shortwave infrared(SWIR) subsystems of WV-3 data. In addition, the Spectral Angle Method and the spectrum index tool of ENVI software were used to extract the relevant alteration information. The WV-3 data is well suited for identifying hydroxy-bearing alteration with rich SWIR bands which distinguish Al-OH-bearing from MgOH-bearing alteration. Hence, this study provides a basis for the prediction of mineral resources in the Pobei area and sets the foundation for WV-3 data to be used as an important tool in extracting alteration information and prospecting practices.Yaqin Sun Shufang Tian Baogang Di 2017Geoscience Frontiers2017,8,5:13
8Hangzhou criteria as downstaging criteria in hepatocellular ca显示文摘Background:The downstaging of hepatocellular carcinoma(HCC)has been confirmed to benefit liver transplantation(LT)patients whose tumors are beyond the transplantation criteria.Milan criteria(MC),a tumor size and number-based assessment,is currently used as the endpoint in these patients.However,many studies believe that tumor biological behavior should be added to the evaluation criteria for downstaging efficacy.Hence,this study aimed to explore the feasibility of Hangzhou criteria(HC),which introduced tumor grading and alpha-fetoprotein in addition to tumor size and number,as an endpoint of downstaging.Methods:We performed a multicenter and retrospective study of 206 patients accepted locoregional therapy(LRT)as downstaging/bridge treatment prior to LT in three centers of China.Results:Recipients were divided into four groups:failed downstaging to the HC(group A,n=46),successful downstaging to the HC(group B,n=30),remained within the HC all the time(group C,n=113),and tumor progressed(group D,n=17).The 3-year HCC recurrence probabilities of groups B and C were not significantly different(10.3%vs.11.6%,P=0.87).The HCC recurrent rate was significantly higher in group A(52.3%)compared with that in group B/C(P<0.05).Seven patients(7/76,9.2%)whose tumor exceeded the the HC were successfully downstaged to the MC,and 39.5%(30/76)to the the HC.In group B,23 patients remained beyond the MC and their survivals were as well as those of patients within the MC.Conclusions:Compared to the MC,HC downstaging criteria can give more HCC patients access to LT and furthermore,the outcome of these patients is the same as those matching MC downstaging criteria.Hangzhou downstaging criteria therefore is applicable in clinical practice.Qi-Fan Zhan Sun-Bin Ling Yi-Nan Deng Qiao-Nan Shan Qian-Wei Ye Sheng-Jun Xu Guang-Jiang Jiang Di Lu Xu-Yong Wei Li Zhuang Wu Zhang Tian Shen Bei-Ni Cen Hai-Yang Xie Ji-Min Liu Jian Wu Shu-Sen Zheng Yang Yang Xiao Xu 2020Hepatobiliary & Pancreatic Diseases International2020,19,4:11
9Targeting HMGB1 for the treatment of sepsis and sepsis-induced organ injury显示文摘High mobility group box 1(HMGB1)is a ubiquitous nuclear protein that is present in almost all cells and regulates the activity of innate immune responses in both intracellular and extracellular settings.Current evidence suggests that HMGB1 plays a pivotal role in human pathological and pathophysiological processes such as the inflammatory response,immune reactions,cell migration,aging,and cell death.Sepsis is a systemic inflammatory response syndrome(SIRS)that occurs in hosts in response to microbial infections with a proven or suspected infectious etiology and is the leading cause of death in intensive care units worldwide,particularly in the aging population.Dysregulated systemic inflammation is a classic characteristic of sepsis,and suppression of HMGB1 may ameliorate inflammation and improve patient outcomes.Here,we focus on the latest breakthroughs regarding the roles of HMGB1 in sepsis and sepsis-related organ injury,the ways by which HMGB1 are released,and the signaling pathways and therapeutics associated with HMGB1.This review highlights recent advances related to HMGB1:the regulation of HMBG1 might be helpful for both basic research and drug development for the treatment of sepsis and sepsis-related organ injury.Chao Deng Lin Zhao Zhi Yang Jia-jia Shang Chang-yu Wang Ming-zhi Shen Shuai Jiang Tian Li Wen-cheng Di Ying Chen He Li Ye-dong Cheng Yang Yang 2022Acta Pharmacologica Sinica2022,43,3:11
10In-situ fabrication of PtSe2/GaN heterojunction for self-powered deep ultraviolet photodetector with ultrahigh current on/off ratio and detectivity显示文摘The research of ultraviolet photodetectors(UV PDs)have been attracting extensive attention,due to their important applications in many areas.In this study,PtSe2/GaN heterojunction is in-situ fabricated by synthesis of large-area vertically standing two-dimensional(2D)PtSe2 film on n-GaN substrate.The PtSe2/GaN heterojunction device demonstrates excellent photoresponse properties under illumination by deep UV light of 265 nm at zero bias voltage.Further analysis reveals that a high responsivity of 193 mA·W^-1,an ultrahigh specific detectivity of 3.8 × 10^14 Jones,linear dynamic range of 155d B and current on/off ratio of^10^8,as well as fast response speeds of 45/102μs were obtained at zero bias voltage.Moreover,this device response quickly to the pulse laser of 266 nm with a rise time of 172 ns.Such high-performanee PtSe2/GaN heteroj u nction UV PD demonstrated in this work is far superior to previously reported results,suggesting that it has great potential for deep UV detection.Ranran Zhuo Longhui Zeng Huiyu Yuan Di Wu Yuange Wang Zhifeng Shi Tingting Xu Yongtao Tian Xinjian Li Yuen Hong Tsang 2019Nano Research2019,12,1:11
11Effects of multidrug resistance, antisense RNA on the chemosensitivity of hepatocellular carcinoma cells显示文摘BACKGROUND: Multidrug resistance is a major obstacle in cancer chemotherapy. We examined whether the antisense RNA of multidrug resistance gene 1 (mdr1) could reverse multidrug resistance in the human hepatocellular carcinoma (HCC) cell line SMMC7721/ADM. METHODS: The recombinant adenoviruses pAdEasy- GFP-ASmdr1 product was produced by the adenoviral vector AdEasy system, which can express antisense RNA against the mdr1 gene. Following that, the recombinant adenovirus was transfected into the P-glycoprotein- producing multidrug resistance cell line, SMMC7721/ADM human HCC cells resistant to adriamycin (ADM) and daunorubicin (DNR). In order to investigate the reversal of multidrug resistance phenotype, we measured the expression of mdr1 mRNA by RT-PCR and the production of P-glycoprotein by flow cytometry. The sensitivities for ADM and DNR SMMC7721/ADM cells were examined by [3-(4, 5-dimethylthi-azol-2-yl)-2,5 diphenyl-terazolium bromide] (MTT) analysis. RESULTS: The low-level expression of mdr1 mRNA and P-glycoprotein production were observed in parental sensitive cells SMMC/7721 in addition to the overexpressionof mdr1 mRNA and P-glycoprotein in SMMC7721/ADM cells. The transfection of antisense-RNA into SMMC7721/ ADM cells resulted in decreases of mdr1 mRNA and P-glycoprotein, but increase of drug sensitivities. The sensitivities of transfected SMMC7721/ADM cells to ADM and DNR in IC50 reduced by 31.25% and 62.96% respectively. CONCLUSIONS: Mdr1 antisense RNA can increase the sensitivities of SMMC7721/ADM cells to anticancer drug by decreasing the expression of the mdr1 gene and inhibiting P-glycoprotein expression. This strategy may be applicable to cancer patients with P-glycoportein mediated multidrug resistance.Bo Li, Tian Ye, Lei Zhao, De-Hua Li, Xing-Hua Gou, Lan-Ying Zhao, Lei Han, Lin Chen, Lu-Nan Yan and Jian-Ping Gong Department of Hepatobiliary Surgery, Second Affiliated Hospital, Chongqing University of Medical Sciences, Chongqing 400010, China Department of Traditional Chinese Surgery, Second Affiliated Hospital, Luzhou Medical College, Luzhou 646000, China Genetic Engineering Laboratory, Chengdu Di’ao Group Co., Ltd., Chengdu 610041, China Department of General Surgery, West China Hospital, Sichuan University, Chengdu 610041, China 2006Hepatobiliary & Pancreatic Diseases International2006,5,4:10
12Future changes in coverage of 1.5℃ and 2℃warming thresholds显示文摘The areas covered by 1.5 ℃ and 2.0 ℃ warming thresholds under RCP2.6, RCP4.5, and RCP8.5 were analyzed based on 22 CMIP5 models. More than 90% of the model runs are in agreement that by the end of the 21 st century, near-surface air temperature changes over ~5%(~2%), ~40%(~18%), and ~92%(~86%)of the globe will cross the 1.5 ℃(2.0 ℃) threshold under RCP2.6, RCP4.5, and RCP8.5, respectively. Under RCP8.5, nearly the whole of North America, Europe + Russia, Africa, and Asia–Russia will cross the 1.5 ℃(2.0 ℃) threshold in ~2050(~2060), while the coverage rates over South America and Oceania are ~80%(~75%) and ~50%(~30%), respectively. The threshold-onset time(TOT) for 2 ℃ warming is earliest over Europe + Russia and North America, followed by Africa, Asia–Russia, South America, and finally Oceania under the RCP4.5 and RCP8.5 scenarios. The TOT for 1.5 ℃ is ~10–30 years ahead of that for 2.0 ℃.di tian wenjie dong han zhang yan guo shili yang tanlong dai 2017Science Bulletin2017,62,21:10
13Hot workability characteristics of Rene88DT superalloy with directionally solidified microstructure显示文摘The hot deformation characteristics of Rene88 DT superalloy with directionally solidified microstructure produced by electroslag remelting continuous directionally solidification(ESR-CDSò) were studied in the temperature range of 1,040–1,140 °C and strain rate range of 0.001–1.000 s-1by hot compression tests. Flow curves for Rene88 DT alloy with initial directionally solidified(DS)microstructure exhibit pronounced peak stresses at the early stage of deformation followed by the occurrence of dynamic softening phenomenon. Rene88 DT alloy with DS microstructure shows higher flow peak stresses compared with HIPed P/M superalloy FGH4096, but the disparities in peak stresses between ESR-CDSed Rene88 DT and HIPed P/M superalloy FGH4096 reduce as temperature increases. The improvement of hot workability of DS alloy with columnar grains avoiding the maximum shear stress comes true. A hot deformation constitutive equation as a function of strain that describes the dependence of flow stress on strain rate and temperature is established. Hot deformation apparent activation energy(Q) varies not only with the strain rate and temperature but also with strain. The strain rate sensitivity exponent(m) map is established at the strain of 0.8, which reveals that global dynamic recrystallization(DRX) shows a relatively high m value in a large strain compression.Optimum parameters are predicted in two regions:T = 1,100–1,130 °C,_e = 0.100–1.000 s-1and T = 1,080–1,100 °C,_e = 0.010–0.100 s-1, which is based on processing maps and deformation microstructure observations.Fu-Lin Li Rui Fu Di Feng Zhi-Ling Tian 2015Rare Metals2015,34,1:9
14cDNA microarray reveals the alterations of cytoskeleton-related genes in osteoblast under high magneto-gravitational environment显示文摘为模仿减少的严肃环境的一个新奇基于地面的模型广泛地在许多地里被使用了的抗磁的悬浮。在这研究,一个专辑设计了超导的磁铁,它能生产三个明显的严肃层次(0, 1,和 2 g ) ,也就是高的磁电机重力的环境(HMGE ) ,被用来模仿空间严肃环境。造骨细胞基因表示侧面上的 HMGE 的效果被 microarray 调查。对抗磁的悬浮环境(0 g ) 敏感的基因,严肃变化,和高磁场变化根据典型房间功能被排序。作为细胞内部的忍受负担的结构,细胞骨架在严肃感觉起一个重要作用。因此, 13 细胞骨架相关的基因根据 microarray 分析的结果被选择,并且这些基因的表情被发现被即时 PCR 在 HMGE 下面改变。基于 PCR 结果, WASF2 的表情(是蛋白质家庭,成员 2 ) , WIPF1 (WAS/WASL 交往蛋白质家庭,成员 1 ) , paxillin,和 talin 1 被西方的污点试金进一步识别。结果显示了那 WASF2, WIPF1 对改变的严肃层次,和 talin 更敏感 1 并且 paxillin 对磁场和严肃变化敏感。我们的调查结果证明 HMGE 能影响造骨细胞基因表示侧面和细胞骨架相关的基因表示。mechanosensitive 基因的鉴定可以提高我们的理解到 microgravity 导致的骨头损失的机制并且可以为阻止并且对待骨头损失或骨质疏松症提供一些潜在的目标。Airong Qian Shengmeng Di Xiang Gao Wei Zhang Zongcheng Tian Jingbao Li Lifang Hu Pengfei Yang Dachuan Yin Peng Shang 2009Acta Biochimica et Biophysica Sinica2009,41,7:8
15Global warming projections using the human–earth system model BNU-HESM1.0显示文摘Future climate change is usually projected by coupled earth system models under specific emission scenarios designed by integrated assessment models(IAMs),and this offline approach means there is no interaction between the coupled earth system models and the IAMs.This paper introduces a new method to design possible future emission scenarios and corresponding climate change, in which a simple economic and climate damage component is added to the coupled earth system model of Beijing Normal University(BNU-ESM). With the growth of population and technological expertise and the declining emission-to-output ratio described in the Dynamic Integrated Climate-Economy model, the projected carbon emission is 13.7 Gt C, resulting in a 2.4 °C warming by the end of the twenty-first century(2080–2099) compared with1980–1999. This paper also suggests the importance of the land and ocean carbon cycle in determining the CO2 concentration in the atmosphere. It is hoped that in the near future the next generation of coupled earth system models that include both the natural system and the social dimension will be developed.Shili Yang Wenjie Dong Jieming Chou Jinming Feng Zhigang Wei Yan Guo Xiaohang Wen Ting Wei Di Tian Xian Zhu Zhiyong Yang 2016Science Bulletin2016,61,23:7
16Shuanghuanglian injection downregulates nuclear factor-kappa B expression in mice with viral encephalitis显示文摘A mouse model of viral encephalitis was induced by intracranial injection of a Coxsackie virus B3 suspension. Quantitative real-time reverse transcription-PCR and western blot assay were applied to detect mRNA and protein expression of intelectin-2 and nuclear factor-kappa B in the viral encephalitis and control groups. Nuclear factor-kappa B and intelectin-2 mRNA and protein expression were significantly increased in mice with viral encephalitis. After intraperitoneal injection of Shuanghuanglian at a dose of 1.5 mg/kg for 5 successive days, intelectin-2 and nuclear factor-kappa B protein and mRNA expression were significantly decreased. To elucidate the relationship between intelectin-2 and nuclear factor-kappa B, mice with viral encephalitis were administered an intracerebral injection of 107 pfu recombinant lentivirus expressing intelectin shRNA. Both protein and mRNA levels of intelectin and nuclear factor-kappa B in brain tissue of mice were significantly decreased. Experimental findings suggest that Shuanghuanglian injection may downregulate nuclear factor-kappa B production via suppression of intelectin production, thus inhibiting inflammation associated with viral encephalitis.Naibing Gu Ye Tian Zhengli Di Caiping Han Hui Lei Gejuan Zhang 2012Neural Regeneration Research2012,7,33:7
17Family-level leaf nitrogen and phosphorus stoichiometry of global terrestrial plants显示文摘Leaf nitrogen(N) and phosphorus(P) concentrations are critical for photosynthesis, growth, reproduction and other ecological processes of plants. Previous studies on large-scale biogeographic patterns of leaf N and P stoichiometric relationships were mostly conducted using data pooled across taxa, while family/genus-level analyses are rarely reported. Here, we examined global patterns of family-specific leaf N and P stoichiometry using a global data set of 12,716 paired leaf N and P records which includes 204 families, 1,305 genera, and 3,420 species. After determining the minimum size of samples(i.e., 35 records), we analyzed leaf N and P concentrations, N:P ratios and N^P scaling relationships of plants for 62 families with 11,440 records. The numeric values of leaf N and P stoichiometry varied significantly across families and showed diverse trends along gradients of mean annual temperature(MAT) and mean annual precipitation(MAP). The leaf N and P concentrations and N:P ratios of 62 families ranged from 6.11 to 30.30 mg g–1, 0.27 to 2.17 mg g–1, and 10.20 to 35.40, respectively. Approximately 1/3–1/2 of the families(22–35 of 62) showed a decrease in leaf N and P concentrations and N:P ratios with increasing MAT or MAP, while the remainder either did not show a significant trend or presented the opposite pattern. Family-specific leaf N^P scaling exponents did not converge to a certain empirical value, with a range of 0.307–0.991 for 54 out of 62 families which indicated a significant N^P scaling relationship. Our results for the first time revealed large variation in the family-level leaf N and P stoichiometry of global terrestrial plants and that the stoichiometric relationships for at least one-third of the families were not consistent with the global trends reported previously. The numeric values of the family-specific leaf N and P stoichiometry documented in the current study provide critical synthetic parameters for biogeographic modeling and for further studies on the physiological and ecological mechanisms underlying the nutrient use strategies of plants from different phylogenetic taxa.Di Tian Zhengbing Yan Suhui Ma Yuehong Ding Yongkai Luo Yahan Chen Enzai Du Wenxuan Han Emoke Dalma Kovacs Haihua Shen Huifeng Hu Jens Kattge Bernhard Schmid Jingyun Fang 2019Science China(Life Sciences)2019,62,8:7
18Effect of a transverse plasma jet on a shock wave induced by a ramp显示文摘We conducted experiments in a wind tunnel with Mach number 2 to explore the evolution of a transverse plasma jet and its modification effect on a shock wave induced by a ramp with an angle of 24°. The transverse plasma jet was created by arc discharge in a small cylindrical cavity with a 2 mm diameter orifice. Three group tests with different actuator arrangements in the spanwise or streamwise direction upstream from the ramp were respectively studied to compare their disturbances to the shock wave. As shown by a time-resolved schlieren system, an unsteady motion of the shock wave by actuation was found: the shock wave was significantly modified by the plasma jet with an upstream motion and a reduced angle. Compared to spanwise actuation, a more intensive impact was obtained with two or three streamwise actuators working together. From shock wave structures, the control effect of the plasma jet on the shock motion based on a thermal effect, a potential cause of shock modification, was discussed. Furthermore, we performed a numerical simulation by using the Improved Delayed Detached Eddy Simulation(IDDES) method to simulate the evolution of the transverse plasma jet plume produced by two streamwise actuators. The results show that flow structures are similar to those identified in schlieren images. Two streamwise vortices were recognized, which indicates that the higher jet plume is the result of the overlap of two streamwise jets.Hongyu WANG Jun LI Di JIN Hui DAI Tian GAN Yun WU 2017Chinese Journal of Aeronautics2017,30,6:7
19Timing the termination of the Doushantuo negative carbon isotope excursion: evidence from U-Pb ages from the Dengying and Liuchapo formations,South China显示文摘The Doushantuo negative carbon isotope excursion(DOUNCE) is the largest known marine inorganic carbon isotope anomaly. The origin of this pronounced negative excursion is still an enigmatic issue that attracts geologists. Time constraints on the excursion are the critical information that would provide insight into its genesis. In previous decades, the timing of its termination has been constrained by the widely cited zircon U-Pb age of 550.5 ± 0.8 Ma for the tuff at the top of the Miaohe Member at the Jiuqunao section in the Yangtze Gorges area, South China. However, results of recent studies indicate that the reliability of this time constraint needs to be re-evaluated. Here, a geochronological study was carried out using two K-bentonites from Fanglong in South China. A K-bentonite in the lower Dengying Formation yielded a U-Pb age of 557 ± 3 Ma, while a K-bentonite in the basal Liuchapo Formation yielded an age of 550 ± 3 Ma. Based on regional correlations between the Ediacaran successions in South China,the age(557 ± 3 Ma) for the K-bentonite in the lower Dengying Formation may serve as a second critical timing constraint for the ending of the DOUNCE. Combined with available estimates of the DOUNCE duration, our new data indicate that the DOUNCE has a maximum onset age ~570 Ma.Mingzhong Zhou Taiyi Luo Warren D.Huff Zhiqing Yang Guanghong Zhou Tian Gan Hua Yang Di Zhang 2018Science Bulletin2018,63,21:6
20A novel design of 3D carbon host for stable lithium metal anode显示文摘Rational design of porous conductive hosts with high electrical conductivity,large surface area,and adequate interior space is desirable to suppressing dendritic lithium growth and accommodating large volume change of lithium metal anode during the Li plating/stripping process.However,due to the conductive nature of the conductive hosts,Li is easily deposited directly on the top of the hosts,which hinders it from fully functioning.To circumvent the issue,in this study,we designed a novel porous carbon host with a gradient-pore-size structure based on one-dimensional(1D)carbon with different diameters.With this kind of host,stable cycling with high and stable Coulombic efficiency of~98%is achieved at 0.5 mA cm^(−2) with an areal capacity of 1 mAh cm^(−2) over 320 cycles.In contrast,the normal three-dimensional(3D)carbon nanotube host presents a moss-like Li morphology with wildly fluctuating Coulombic efficiency after 100 cycles.The results reveal that the unique gradient-pore-size structure of the 3D conductive host greatly improves the performance of lithium metal batteries.Hang Liu Jie Di Ping Wang Rui Gao Han Tian Pengfei Ren Qingxi Yuan Wanxia Huang Ruiping Liu Qiang Liu Ming Feng 2022Carbon Energy2022,4,4:5
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