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Inter-Regional Comparisons on the Quaternary Large Mammalian Faunas between China and Sub-Saharan Africa 被引量:2
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作者 TONG Haowen HU Nan +1 位作者 LIU Jinyi Ronald CLARKE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第1期91-106,共16页
The current and dominant theory about the origin of modern humans is the out-of-Africa hypothesis, which asserts that populations of Homo sapiens left Africa 100,000 years ago and replaced indigenous populations of hu... The current and dominant theory about the origin of modern humans is the out-of-Africa hypothesis, which asserts that populations of Homo sapiens left Africa 100,000 years ago and replaced indigenous populations of humans in Eurasia. Many scholars equated the out-of-Africa dispersal of humans with paleoenvironmental changes. However, until now, few have paid special attention to the faunal data and whether or not faunal patterns are supportive of the popular theory. Recent comparative study of the Chinese fauna shows that the communication of faunas between Africa and East Asia could have occurred during the Neogene, but it was very limited during the Pleistocene. In the Chinese Quaternary fauna, only 16% of the genera are also present in the sub-Saharan African fauna. There is also no element among the dominant taxa of the Chinese Quaternary fauna which can be related to the African fauna. There is no reliable proof for the existence of Hippopotamus and Giraffa, as well as Panthera leo, during the Quaternary in China. Two controversial taxa are Acinonyx and Crocuta, about which there is still argument concerning their species identification in Eurasia. It is possible that both of the genera have co-specific taxa in Africa and Eurasia. Although the two genera are confined to Africa today, they did have a long evolutionary history in China. For the Out of Africa hypothesis for Homo sapiens, the implications of the limited faunal interchanges between China and Africa are not completely clear yet. 展开更多
关键词 large mammals faunal comparisons QUATERNARY out of Africa theory Sub-SaharanAfrica China
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Global Research Progress on Municipal Waste and Future Prospect Based on the Cross-national Comparisons
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作者 ZHANG Yuxin LIU Xiaoqian +2 位作者 YAN Xiaoxia MA Sike MAO Weiyun 《Chinese Geographical Science》 SCIE CSCD 2024年第2期250-264,共15页
Due to the acceleration of urbanization,the municipal waste(MW)problem has transformed into a global challenge for urb-an sustainability.To elucidate historical trends,current focal points,and future directions in MW ... Due to the acceleration of urbanization,the municipal waste(MW)problem has transformed into a global challenge for urb-an sustainability.To elucidate historical trends,current focal points,and future directions in MW research,we conducted a bibliometric analysis and employed knowledge graph visualization to scrutinize a total of 34212 articles,which were published between 1991 and 2021 in the Web of Science(WoS)core database.The results indicated that current major research themes encompass waste classifica-tion and recycling,waste management and public behavior,waste disposal methods and technologies,as well as environmental impact and evaluation.There has been a shift in the research focus from the environmental impacts of waste incineration to sustainable manage-ment related issues.A comparison of research from six typical countries revealed the differences in research priorities and techniques advantages.Scholars from the USA and Britain initiated MW research earlier than other countries and investigated management issues in depth,such as public behavior and willingness to pay.Meanwhile,Japanese,German,and Swedish scholars conducted extensive studies on advanced waste treatment technologies,such as disposal and recycling,risk assessment,and waste-to-energy techniques.Chinese scholars placed particular emphasis on end-of-pipe treatments and their associated environmental impacts.Hotspots and poten-tial future frontiers were identified by burst detection analysis.Keywords with high value of burst index(BI)worldwide are food waste and circular economy.Chinese scholars have put great efforts on waste environmental impact and its recycling technologies,while we’re expecting to further investigating vulnerable population.Furthermore,this study contributes to bridging the regional gap of scientific research among different countries and fostering international collaboration. 展开更多
关键词 BIBLIOMETRICS municipal waste(MW) CiteSpace hotspot prediction burst index(BI) SUSTAINABILITY cross-national comparison Web of Science(WoS)
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Natural gas characteristics and gas-source comparisons of the Lower Triassic Feixianguan Formation,Eastern Sichuan Basin,China
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作者 Zi-Yun Zheng Yin-Hui Zuo +5 位作者 Hua-Guo Wen De-Ming Li Yang Luo Jia-Zhen Zhang Mei-Hua Yang Jian-Cheng Zeng 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1458-1470,共13页
There is great controversy regarding the origin and source of natural gas in the Lower Triassic Feix-ianguan Formation in the Eastern Sichuan Basin.This seriously restricts the study of natural gas dy-namics in the Fe... There is great controversy regarding the origin and source of natural gas in the Lower Triassic Feix-ianguan Formation in the Eastern Sichuan Basin.This seriously restricts the study of natural gas dy-namics in the Feixianguan Formation and thus hampers natural gas exploration in the region,so further study is urgently required.Using experimental tests of natural gas composition,stable isotopes,and noble gas isotopes with gas chromatography(GC)and mass spectrometry(MS)studies of source rock and reservoir asphalt saturated hydrocarbons,the natural gas geochemical characteristics,the genetic identification and a gas-source comparison of the Feixianguan Formation were studied.Then,con-strained by the thermal history,the histories of gas generation and expulsion were restored by basin simulation technology.Finally,a gas accumulation model was established for the Feixianguan Formation.The results showed that(1)the H_(2)S-rich and H2S-poor gas reservoirs of the Feixianguan Formation are distributed on the east and west sides of the Kaijiang-Liangping trough in the Eastern Sichuan Basin,respectively.The carbon and hydrogen isotope compositions of the natural gas in the gas reservoirs are generally heavy and have typical characteristics of high-maturity dry gas reservoirs.(2)The natural gas of the Feixianguan Formation is organic thermogenic gas,which is mainly oil-type gas generated by the secondary cracking of crude oil.The gas-generating parent material is mainly type II kerogen.(3)The natural gas of the Feixianguan Formation in the Eastern Sichuan Basin was mainly generated by argil-laceous source rocks of the Upper Permian Longtan Formation.(4)Natural gas accumulation occurred as follows:the paleo-structure heights were filled with crude oil in the Early Jurassic,and paleo-oil res-ervoirs were formed in the Feixianguan Formation;during the Middle-Late Jurassic,the paleo-oil res-ervoirs were cracked when the reservoir temperatures rose above 160 C,and paleo-gas reservoirs were formed.Since the end of the Late Jurassic,the paleo-gas reservoirs have been adjusted and reformed to form the present-day natural gas reservoirs.These results provide a basis for studying natural gas accumulation dynamics of the Feixianguan Formation in the Eastern Sichuan Basin. 展开更多
关键词 Eastern Sichuan Basin Feixianguan Formation Natural gas origin Gas-source comparison Longtan Formation
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Efficacy of fexuprazan compared with rebamipide in Korean patients with gastritis:A matching-adjusted indirect comparison
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作者 Gwang Ha Kim Hang Lak Lee 《World Journal of Clinical Cases》 SCIE 2024年第19期3890-3897,共8页
BACKGROUND Gastritis is one of the most frequently diagnosed diseases requiring medical treatment in South Korea.Fexuprazan,a novel potassium-competitive acid blocker,has been approved for treating gastritis and erosi... BACKGROUND Gastritis is one of the most frequently diagnosed diseases requiring medical treatment in South Korea.Fexuprazan,a novel potassium-competitive acid blocker,has been approved for treating gastritis and erosive esophagitis.Meanwhile,rebamipide is the most commonly used mucoprotective agent for acute and chronic gastritis in real-world settings in South Korea.However,there have been no studies comparing the efficacy of these two drugs yet.AIM To compare the efficacy of fexuprazan with that of rebamipide for acute and chronic gastritis.METHODS This was a matching-adjusted indirect comparison.Individual patient data from a phase III study of fexuprazan(10 mg BID)were compared with cumulative data from two matching studies of rebamipide(100 mg TID).Erosion improvement and healing rates were compared between two weeks of fexurapan,two weeks of rebamipide,and four weeks of rebamipide.The two main outcome variables were presented as percentages,and the risk differences(RD)and 95%confidence intervals(CI)were calculated for the relative treatment effects.RESULTS In the primary analysis,the erosion improvement and healing rates after a twoweek treatment with fexuprazan were 64.5%and 53.2%,respectively,while a twoweek treatment with rebamipide resulted in erosion improvement and healing rates of 43.6%(RD:21.0%;95%CI:9.6-32.3;P<0.01)and 35.6%(RD:17.6%;95%CI:6.1-29.2;P=0.003),respectively.In the additional analysis,the erosion improvement and healing rates for the two-week fexuprazan treatment(64.2%and 51.2%,respectively)were similar to those obtained during a four-week treatment with rebamipide(60.6%;RD:3.6%;95%CI:-9.8,17.0;P=0.600 and 53.5%;RD:-2.3%;95%CI:-16.1,11.5;P=0.744,respectively).CONCLUSION The two-week fexuprazan treatment was superior to the two-week rebamipide treatment and similar to the fourweek rebamipide treatment for patients with gastritis. 展开更多
关键词 GASTRITIS Erosive gastritis Fexuprazan REBAMIPIDE Matching-adjusted indirect comparison Indirect treatment comparison
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Accuracy comparison and improvement for state of health estimation of lithium-ion battery based on random partial recharges and feature engineering
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作者 Xingjun Li Dan Yu +1 位作者 Søren Byg Vilsen Daniel Ioan Stroe 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期591-604,共14页
State of health(SOH)estimation of e-mobilities operated in real and dynamic conditions is essential and challenging.Most of existing estimations are based on a fixed constant current charging and discharging aging pro... State of health(SOH)estimation of e-mobilities operated in real and dynamic conditions is essential and challenging.Most of existing estimations are based on a fixed constant current charging and discharging aging profiles,which overlooked the fact that the charging and discharging profiles are random and not complete in real application.This work investigates the influence of feature engineering on the accuracy of different machine learning(ML)-based SOH estimations acting on different recharging sub-profiles where a realistic battery mission profile is considered.Fifteen features were extracted from the battery partial recharging profiles,considering different factors such as starting voltage values,charge amount,and charging sliding windows.Then,features were selected based on a feature selection pipeline consisting of filtering and supervised ML-based subset selection.Multiple linear regression(MLR),Gaussian process regression(GPR),and support vector regression(SVR)were applied to estimate SOH,and root mean square error(RMSE)was used to evaluate and compare the estimation performance.The results showed that the feature selection pipeline can improve SOH estimation accuracy by 55.05%,2.57%,and 2.82%for MLR,GPR and SVR respectively.It was demonstrated that the estimation based on partial charging profiles with lower starting voltage,large charge,and large sliding window size is more likely to achieve higher accuracy.This work hopes to give some insights into the supervised ML-based feature engineering acting on random partial recharges on SOH estimation performance and tries to fill the gap of effective SOH estimation between theoretical study and real dynamic application. 展开更多
关键词 Feature engineering Dynamic forklift aging profile State of health comparison Machine learning Lithium-ion batteries
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Efficacy comparison of multipoint and single point scanning panretinal laser photocoagulation in non-proliferative diabetic retinopathy treatment
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作者 Yang-Zhou Zhang Hua Gong +2 位作者 Juan Yang Ji-Pu Bu Hui-Ling Yang 《World Journal of Diabetes》 SCIE 2024年第8期1734-1741,共8页
BACKGROUND Non-proliferative diabetic retinopathy(NPDR)poses a significant challenge in diabetes management due to its microvascular changes in the retina.Laser photocoagulation,a conventional therapy,aims to mitigate... BACKGROUND Non-proliferative diabetic retinopathy(NPDR)poses a significant challenge in diabetes management due to its microvascular changes in the retina.Laser photocoagulation,a conventional therapy,aims to mitigate the risk of progressing to proliferative diabetic retinopathy(PDR).AIM To compare the efficacy and safety of multi-spot vs single-spot scanning panretinal laser photocoagulation in NPDR patients.METHODS Forty-nine NPDR patients(86 eyes)treated between September 2020 and July 2022 were included.They were randomly allocated into single-spot(n=23,40 eyes)and multi-spot(n=26,46 eyes)groups.Treatment outcomes,including bestcorrected visual acuity(BCVA),central macular thickness(CMT),and mean threshold sensitivity,were assessed at predetermined intervals over 12 months.Adverse reactions were also recorded.RESULTS Energy levels did not significantly differ between groups(P>0.05),but the multi-spot group exhibited lower energy density(P<0.05).BCVA and CMT improvements were noted in the multi-spot group at one-month posttreatment(P<0.05).Adverse reaction incidence was similar between groups(P>0.05).CONCLUSION While energy intensity and safety were comparable between modalities,multi-spot scanning demonstrated lower energy density and showed superior short-term improvements in BCVA and CMT for NPDR patients,with reduced laser-induced damage. 展开更多
关键词 Panretinal laser photocoagulation Non-proliferative diabetic retinopathy Efficacy comparison Multipoint Single point Treatment assessment
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Comparison and Selection of Water Restoration Techniques for Artificial Landscape Lakes in Nantong City
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作者 Shengrong YAN Yuyue MA +2 位作者 Yi'an CHEN Jiafeng SUN Mingqing CHEN 《Agricultural Biotechnology》 2024年第3期90-92,95,共4页
As an important part of urban infrastructure,urban water system is of great and far-reaching significance for ensuring urban flood control and waterlogging safety,protecting ecological environment and building livable... As an important part of urban infrastructure,urban water system is of great and far-reaching significance for ensuring urban flood control and waterlogging safety,protecting ecological environment and building livable homes.Taking the urban water system of Nantong as an example,Nantong Water Resources Bureau issued R evision of Nantong Urban Water System Planning in 2017,and put forward the construction of the"two circles,eight lakes and nine veins"water system layout,giving new vitality to the urban water system.In view of problems existing in newly excavated artificial landscape lakes,such as fragile water ecosystem,strong eutrophication trend,poor environmental sensory effect and unsatisfactory water landscape effect,it is urgent to study the in-situ water ecological restoration technique of"algae-controlling zooplankton+submerged plant community"to build a"grass-type clear water"ecosystem for artificial landscape lakes,so as to improve the water sensory index and self-purification ability and finally realize the double improvement of"sensory effect and water quality"of artificial landscape lakes. 展开更多
关键词 Water body remediation technique Artificial landscape lake comparison and selection Nantong City
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Direct Pointwise Comparison of FE Predictions to StereoDIC Measurements:Developments and Validation Using Double Edge-Notched Tensile Specimen
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作者 Troy Myers Michael A.Sutton +2 位作者 Hubert Schreier Alistair Tofts Sreehari Rajan Kattil 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1263-1298,共36页
To compare finite element analysis(FEA)predictions and stereovision digital image correlation(StereoDIC)strain measurements at the same spatial positions throughout a region of interest,a field comparison procedure is... To compare finite element analysis(FEA)predictions and stereovision digital image correlation(StereoDIC)strain measurements at the same spatial positions throughout a region of interest,a field comparison procedure is developed.The procedure includes(a)conversion of the finite element data into a triangular mesh,(b)selection of a common coordinate system,(c)determination of the rigid body transformation to place both measurements and FEA data in the same system and(d)interpolation of the FEA nodal information to the same spatial locations as the StereoDIC measurements using barycentric coordinates.For an aluminum Al-6061 double edge notched tensile specimen,FEA results are obtained using both the von Mises isotropic yield criterion and Hill’s quadratic anisotropic yield criterion,with the unknown Hill model parameters determined using full-field specimen strain measurements for the nominally plane stress specimen.Using Hill’s quadratic anisotropic yield criterion,the point-by-point comparison of experimentally based full-field strains and stresses to finite element predictions are shown to be in excellent agreement,confirming the effectiveness of the field comparison process. 展开更多
关键词 StereoDIC spatial co-registration data transformation finite element simulations point-wise comparison of measurements and FEA predictions double edge notch specimen model validation
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对《Drug Facts & Comparisons》的分析与介绍
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作者 胡欣 乔彦 杨莉萍 《中国执业药师》 CAS 2011年第6期50-52,共3页
《Drug Facts & Comparisons》是目前在全球医疗卫生专业人员中广泛使用的、极具影响力的药物信息参考工具书之一。本文通过对该书主要内容、数据特点、编辑及更新流程、编辑出版沿革等信息的分析与介绍,为国内医药学专业人员学习... 《Drug Facts & Comparisons》是目前在全球医疗卫生专业人员中广泛使用的、极具影响力的药物信息参考工具书之一。本文通过对该书主要内容、数据特点、编辑及更新流程、编辑出版沿革等信息的分析与介绍,为国内医药学专业人员学习、了解、获取国外先进的药学信息资源提供参考。 展开更多
关键词 药学信息 药物事实与比较 参考工具书
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Therapeutic effect of regulating autophagy in spinal cord injury: a network meta-analysis of direct and indirect comparisons 被引量:5
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作者 Duo Zhang Di Zhu +4 位作者 Fang Wang Ji-Chao Zhu Xu Zhai Yuan Yuan Chen-Xi Li 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第6期1120-1132,共13页
Objective:An increasing number of studies indicate that autophagy plays an important role in the pathogenesis of spinal cord injury,and that regulating autophagy can enhance recovery from spinal cord injury.However,th... Objective:An increasing number of studies indicate that autophagy plays an important role in the pathogenesis of spinal cord injury,and that regulating autophagy can enhance recovery from spinal cord injury.However,the effect of regulating autophagy and whether autophagy is detrimental or beneficial after spinal cord injury remain unclear.Therefore,in this study we evaluated the effects of autophagy regulation on spinal cord injury in rats by direct and indirect comparison,in an effort to provide a basis for further research.Data source:Relevant literature published from inception to February 1,2018 were included by searching Wanfang,CNKI,Web of Science,MEDLINE(OvidSP),PubMed and Google Scholar in English and Chinese.The keywords included"autophagy","spinal cord injury",and"rat".Data selection:The literature included in vivo experimental studies on autophagy regulation in the treatment of spinal cord injury(including intervention pre-and post-spinal cord injury).Meta-analyses were conducted at different time points to compare the therapeutic effects of promoting or inhibiting autophagy,and subgroup analyses were also conducted.Outcome measure:Basso,Beattie,and Bresnahan scores.Results:Of the 622 studies,33 studies of median quality were included in the analyses.Basso,Beattie,and Bresnahan scores were higher at 1 day(MD=1.80,95%CI:0.81-2.79,P=0.0004),3 days(MD=0.92,95%CI:0.72-1.13,P<0.00001),1 week(MD=2.39,95%CI:1.85-2.92,P<0.00001),2 weeks(MD=3.26,95%CI:2.40-4.13,P<0.00001),3 weeks(MD=3.13,95%CI:2.51-3.75,P<0.00001)and 4 weeks(MD=3.18,95%CI:2.43-3.92,P<0.00001)after spinal cord injury with upregulation of autophagy compared with the control group(drug solvent control,such as saline group).Basso,Beattie,and Bresnahan scores were higher at 1 day(MD=6.48,95%CI:5.83-7.13,P<0.00001),2 weeks(MD=2.43,95%CI:0.79-4.07,P=0.004),3 weeks(MD=2.96,95%CI:0.09-5.84,P=0.04)and 4 weeks(MD=4.41,95%CI:1.08-7.75,P=0.01)after spinal cord injury with downregulation of autophagy compared with the control group.Indirect comparison of upregulation and downregulation of autophagy showed no differences in Basso,Beattie,and Bresnahan scores at 1 day(MD=-4.68,95%CI:-5.840 to-3.496,P=0.94644),3 days(MD=-0.28,95%CI:-2.231-1.671,P=0.99448),1 week(MD=1.83,95%CI:0.0076-3.584,P=0.94588),2 weeks(MD=0.81,95%CI:-0.850-2.470,P=0.93055),3 weeks(MD=0.17,95%Cl:-2.771-3.111,P=0.99546)or 4 weeks(MD=-1.23,95%Cl:-4.647-2.187,P=0.98264)compared with the control group.Conclusion:Regulation of autophagy improves neurological function,whether it is upregulated or downregulated.There was no difference between upregulation and downregulation of autophagy in the treatment of spinal cord injury.The variability in results among the studies may be associated with differences in research methods,the lack of clearly defined autophagy characteristics after spinal cord injury,and the limited autophagy monitoring techniques.Thus,methods should be standardized,and the dynamic regulation of autophagy should be examined in future studies. 展开更多
关键词 AUTOPHAGY Basso Beattie and Bresnahan SCORES indirect comparison meta-analysis nerve REGENERATION neural REGENERATION NEUROLOGICAL function rat models regulation spinal CORD injury strategy analysis
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平“语”近人中课程思政元素comparison的应用及分析
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作者 武悦 《海外英语》 2023年第13期85-87,共3页
文章的研究目的是理解平“语”近人中comparison(比喻)的用法,平“语”近人中课程思政的内容和其背后的真实含义具有重要的教育意义。文章以话语中课程思政元素的comparison主要例子作为研究对象,来探讨和研究平“语”近人话语中的关于c... 文章的研究目的是理解平“语”近人中comparison(比喻)的用法,平“语”近人中课程思政的内容和其背后的真实含义具有重要的教育意义。文章以话语中课程思政元素的comparison主要例子作为研究对象,来探讨和研究平“语”近人话语中的关于comparison的应用并且加以分析。 展开更多
关键词 平“语”近人 课程思政元素 comparison应用分析
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Comparisons of OCO-2 satellite derived XCO_(2)with in situ and modeled data over global ocean 被引量:4
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作者 Siqi Zhang Yan Bai +3 位作者 Xianqiang He Haiqing Huang Qiangkun Zhu Fang Gong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第4期136-142,共7页
Atmospheric CO_(2)is one of key parameters to estimate air-sea CO_(2)flux.The Orbiting Carbon Observatory-2(OCO-2)satellite has observed the column-averaged dry-air mole fractions of global atmospheric carbon dioxide(... Atmospheric CO_(2)is one of key parameters to estimate air-sea CO_(2)flux.The Orbiting Carbon Observatory-2(OCO-2)satellite has observed the column-averaged dry-air mole fractions of global atmospheric carbon dioxide(XCO_(2))since 2014.In this study,the OCO-2 XCO_(2)products were compared between in-situ data from the Total Carbon Column Network(TCCON)and Global Monitoring Division(GMD),and modeling data from CarbonTracker2019 over global ocean and land.Results showed that the OCO-2 XCO_(2)data are consistent with the TCCON and GMD in situ XCO_(2)data,with mean absolute biases of 0.25×10^(-6)and 0.67×10^(-6),respectively.Moreover,the OCO-2 XCO_(2)data are also consistent with the CarbonTracker2019 modeling XCO_(2)data,with mean absolute biases of 0.78×10^(-6)over ocean and 1.02×10^(-6)over land.The results indicated the high accuracy of the OCO-2 XCO_(2)product over global ocean which could be applied to estimate the air-sea CO_(2)flux. 展开更多
关键词 XCO_(2) OCO-2 comparison in situ modeling data
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Comparisons and Assessment of Forest Fire Danger Systems 被引量:1
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作者 TianXiao-rui DouglasJMcrae +4 位作者 DenBoychu JinJi-zhong GaoCheng-da ShuLi-fu WangMing-yu 《Forestry Studies in China》 CAS 2005年第1期53-61,共9页
The paper gives a brief description about the current main forest fire danger rating systems in the world, which in- clude forest fire danger rating system used in Canada, USA, Australia, and other countries. It show... The paper gives a brief description about the current main forest fire danger rating systems in the world, which in- clude forest fire danger rating system used in Canada, USA, Australia, and other countries. It shows the composition, structure and development of the main fire danger rating systems. The limitations of those systems are also discussed. Through a comparison of the three main forest fire danger rating systems the paper describes their differences on development, fuel complex descriptions, inputs and outputs, and their applications and finds that the technologies of the Canadian forest fire danger rating system can be adopted for China to develop a national forest fire danger rating system. Two steps are needed to develop our own national forest fire danger rating system. Firstly, we apply the CFFDRS directly. Then some studies should be done to calibrate the FDRS to local weather and fuel characteristics. 展开更多
关键词 fire danger rating system comparison ASSESSMENT
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COMPARISONS OF THE WEST PACIFIC SUBTROPICAL HIGH AND THE SOUTH ASIA HIGH BETWEEN NCEP/NCAR AND ECMWF REANALYSIS DATASETS 被引量:4
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作者 陈雯 智协飞 《Journal of Tropical Meteorology》 SCIE 2008年第2期121-124,共4页
Comparisons of the west Pacific subtropical high with the South Asia High are made using the NCEP/NCAR and ECMWF 500 hPa and 100 hPa monthly boreal geopotential height fields for the period 1961-2000. Discrepancies ar... Comparisons of the west Pacific subtropical high with the South Asia High are made using the NCEP/NCAR and ECMWF 500 hPa and 100 hPa monthly boreal geopotential height fields for the period 1961-2000. Discrepancies are found for the time prior to 1980. The west Pacific subtropical high in the NCEP/NCAR data is less intense than in ECMWF data before 1980. The range and strength of the west Pacific subtropical high variation described by the NCEP/NCAR data are larger than those depicted by ECMWF data. The same situation appears in the 100-hPa geopotential field. These discoveries suggest that the interdecadal variation of the two systems as shown by the NCEP/NCAR data may not be true. Besides, the South Asia High center in the NCEP/NCAR data is obviously stronger than in the ECMWF data during the periods 1969, 1979-1991 and 1992-1995. Furthermore, the range is larger from 1992 to 1995. 展开更多
关键词 reanalysis datasets west Pacific subtropical high South Asia High comparisons
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Inter-hemispheric comparisons of geospace environment in the polar regions—A proposed cooperative research program between China and Norway 被引量:1
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作者 刘瑞源 杨惠根 +2 位作者 胡红桥 Asgeir Brekke Jφran Moen 《Chinese Journal of Polar Science》 2002年第1期1-6,共6页
The Chinese Zhongshan Station in Antarctica and the stations in Svalbard (Auroral station at Longyearbyen and NP station at Ny lesund) are closely magnetic conjugate. All of them are equipped similar measurement inst... The Chinese Zhongshan Station in Antarctica and the stations in Svalbard (Auroral station at Longyearbyen and NP station at Ny lesund) are closely magnetic conjugate. All of them are equipped similar measurement instruments dealing with upper atmospheric physics. Therefore, there is a good reason to conduct a cooperative research program between China and Norway to do the inter hemispheric comparisons of geospace environment in the polar regions. It will make significant contribution to further understanding of the coupled magnetosphere ionsphere system. The scientific aims of the cooperative project are: to experimentally verify the modeled complicated conjugate relationship between Zhongshan Station in the Antarctic and Svalbard in the Arctic. To derive knowledge from the conjugate characteristics of auroral formations, ionospheric features and space plasma waves in the polar regions, which in turn will lead to better understanding of the solar wind magnetosphere ionosphere coupling processes. The proposed research contents, research methods and experimental techniques are discussed, and the manners of the cooperative research are suggested in the paper. 展开更多
关键词 geospace comparison CUSP Zhongshan Station Svalbard.
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Stock Market: Comparisons of the Achievements of China's State-owned Enterprises and Private-owned Enterprises 被引量:1
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作者 Sen Wang 《Chinese Business Review》 2004年第9期67-75,共9页
With China taking its reform and opening policy, the private economy has been developed rapidly now, especially going public. It is discovered that there are two ways of entering China's stock market: one is direct ... With China taking its reform and opening policy, the private economy has been developed rapidly now, especially going public. It is discovered that there are two ways of entering China's stock market: one is direct listing; the other is indirect listing. Private enterprise studied in this paper excludes state-owned economy. Since 1996 in China, a number of private listing corporations have been going increased year by year, and indirect listing has become the main form of private enterprises' access to stock market. In the paper, the author made a substantial evidence analysis on the 53 private corporations, which have entered China's stock market by the end of 1998. By means of the SHAZAM regression test analysis, the author draws a surprising conclusion: as far as private listing companies are concerned, state-ownership enterprise's efficiency is more satisfied than private ones. This indicates that improving the management of private enterprise has already been on the agenda. 展开更多
关键词 SOE POE comparison
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Comparisons on Mineralogy and Lithology between Paleozoic Marine and Lacustrine Dolostones, Northern China 被引量:1
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作者 LI Hong LIU Yiqun +3 位作者 NIU Yuanzhe FENG Shihai LEI Yun LIU Yongjie 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期281-282,共2页
1 Introduction Dolomite[Ca Mg(CO3)2],a common mineral in carbonate rocks,can be found in various geological settings from Precambrian to modern age,and is widely reported in almost all sedimentary and digenetic
关键词 comparisons on Mineralogy and Lithology between Paleozoic Marine and Lacustrine Dolostones Northern China
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Global Comparisons of Geological Heritages in Alxa and Establishment of Global Geopark
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作者 Yuhuan Geng~(1,2),Mingzhong Tian~1,Siwen Liu~1,Guoqing Zhang~1,Jing Guo~1 1.School of the Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China. 2.Department of Geography,McGill University,Montreal,Quebec H3A2K6,Canada 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期299-299,共1页
Alxa,located at the junction of the North China plate and the Tarim plate,is characterized by complicated geological conditions and obvious climate changes.Unique geological and geographic conditions formed a variety ... Alxa,located at the junction of the North China plate and the Tarim plate,is characterized by complicated geological conditions and obvious climate changes.Unique geological and geographic conditions formed a variety of landscapes in Alxa, including desert landscape,Gobi landscape,wind -erosion landform,canyon landform,etc.This paper compares and evaluates the scientific interests 展开更多
关键词 Alxa GEOLOGICAL heritages GEOPARK comparison
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Multiomics comparison among populations of three plant sources of Amomi Fructus 被引量:1
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作者 Xinlian Chen Shichao Sun +15 位作者 Xiaoxu Han Cheng Li Fengjiao Wang Bao Nie Zhuangwei Hou Song Yang Jiaojiao Ji Ge Li Yanqian Wang Xiaoyu Han Jianjun Yue Cui Li Wei Li Lixia Zhang Depo Yang Li Wang 《Horticulture Research》 SCIE CSCD 2023年第8期129-142,共14页
Amomi Fructus(Sharen,AF)is a traditional Chinese medicine(TCM)from three source species(or varieties),including Wurfbainia villosa var.villosa(WVV),W.villosa var.xanthioides(WVX),or W.longiligularis(WL).Among them,WVV... Amomi Fructus(Sharen,AF)is a traditional Chinese medicine(TCM)from three source species(or varieties),including Wurfbainia villosa var.villosa(WVV),W.villosa var.xanthioides(WVX),or W.longiligularis(WL).Among them,WVV has been transplanted from its top-geoherb region,Guangdong,to its current main production area,Yunnan,for>50 years in China.However,the genetic and transcriptomic differentiation among multiple AF source species(or varieties)and between the origin and transplanted populations of WVV is unknown.In our study,the observed overall higher expression of terpenoid biosynthesis genes in WVV than in WVX provided possible evidence for the better pharmacological effect of WVV.We also screened six candidate borneol dehydrogenases(BDHs)that potentially catalyzed borneol into camphor in WVV and functionally verified them.Highly expressed genes at the P2 stage of WVV,Wv05G1424 and Wv05G1438,were capable of catalyzing the formation of camphor from(+)-borneol,(-)-borneol and DL-isoborneol.Moreover,the BDH genes may experience independent evolution after acquiring the ancestral copies,and the following tandem duplications might account for the abundant camphor content in WVV.Furthermore,four populations of WVV,WVX,and WL are genetically differentiated,and the gene flow from WVX to WVV in Yunnan contributed to the greater genetic diversity in the introduced population(WVV-JH)than in its top-geoherb region(WVV-YC),which showed the lowest genetic diversity and might undergo genetic degradation.In addition,terpene synthesis(TPS)and BDH genes were selected among populations of multiple AF source species(or varieties)and between the top-and non-top-geoherb regions,which might explain the difference in metabolites between these populations.Our findings provide important guidance for the conservation,genetic improvement,and industrial development of the three source species(or varieties)and for identifying top-geoherbalism with molecular markers,and proper clinical application of AF. 展开更多
关键词 HERBAL AMONG comparison
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Comparisons of particles thermal behavior between Fe-base alloy and boron carbide during plasma transferred-arc powder surfacing
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作者 王惜宝 《China Welding》 EI CAS 2003年第1期67-71,共5页
Comparisons of particle’s thermal behavior between Fe base alloy and boron carbide in plasma transferred arc (PTA) space was made based on theoretical evaluation results in this article. It was found that most of t... Comparisons of particle’s thermal behavior between Fe base alloy and boron carbide in plasma transferred arc (PTA) space was made based on theoretical evaluation results in this article. It was found that most of the Fe base particles would be fully melted while they transporting through the central plasma field with 200 A surfacing currents. And the particles with a diameter less than 0.5×10 -4 m might be fully evaporated. However, for the boron carbide (B 4C) particles, only the one with a diameter less than 0.5×10 -4 m could be melted in the same PTA space. Most of B 4C particles are only preheated at its solid state when they were fed through the central field of PTA plasma when the surfacing current is equal to or less than 200 A . When the arc current was smaller than100 A , only the particles smaller than 0.5×10 -4 m could be melted in the PTA space for the Fe base alloy. Almost none of the discussed B 4C particles could be melted in the 100 A PTA space. 展开更多
关键词 comparison particle Fe base alloy B 4C plasma transferred arc
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