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On the True Face of the Economic Statistics

Journal of Mathematics and System Science 2014年第7期4卷 472-478页

作者： zhu yu chen xiaoru wang lei Xi'an University of Finance and Economics Xi'an China

In 2012, China National Ministry of Education issued a new undergraduate course catalog, economic statistics to be classified as a second level discipline of applied economics. However, what specific content should be included in the second level discipline has become a very important issue. What should be taught to students or how can they adapt to the needs of the social market aroused a wide attention. For this case, the National Ministry of Education has given a clearly provision for economic statistics＇ core courses, but whether these main courses can reflect the actual needs and characteristics of economic statistics or not still needs some considerations and discussions. This article started from the angle of the studies on China and the U.S. Journals concerning economic statistics. Using text mining by R, a recent mainstream statistical analysis software, gives a comparative analysis on the contents of economic statistics for recent decades. We created wordcloud about the contents of core statistical journals by R which can help us visually examine the course of economic statistics discipline development for the comparative study. Besides, we drew a conclusion that there were significant differences between China and America＇s economic statistics, the main difference is the United States pay more attention to the exploration of new methods and be able to adapt to market demand, the development of China＇s economic statistics are still more traditional, it need a better understanding of the multi-disciplinary knowledge of education, such as Bayesian and dynamics. Another is that the curriculum of China＇s economic statistics are corrected for China＇s actual situation, a new training program pay more attention to students＇ practical ability and social practice. There are a lot of practical problems remain untouched or unsolved which need efforts of decades probably.

关键词： Economic statistics text mining word cloud comparative analysis

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A Novel Design of Mechanical Switch for the High Overload Environment

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Computers, Materials & Continua 2020年第10期65卷 419-432页

作者： yu wang chen Liu lei wang Lihua zhu School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China School of Computing and Information Technology University of WollongongWollongongNSW 2522Australia

The internal structure of the inertial measurement unit(IMU)in active state is easily damaged in the high overload *** that the IMU is usually required to be powered within the disappearance of the high *** this paper,a mechanical switch is designed to enable the IMU based on the analysis of the impact of high overload on the power-supply *** which,parameters of mechanical switch are determined through theoretical calculation and data *** innovation of the proposed structure lies in that the mechanical switch is triggered through the high overload process and could provide a delay signal for the *** all,the proposed switch is tested through mechanical simulation,impact test and practical *** experimental results show that the designed mechanical switch can effectively and reliably provide the delay for the circuit and guarantee operation of the IMU under high overload.

关键词： High overload environment mechanical switch power-supply circuit circuit delayed closing data analysis

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Thermal effects on fracture toughness of cracked straight-through Brazilian disk green sandstone and granite

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第5期14卷 1447-1460页

作者： lei Zhou Weiting Gao Liyuan yu Zheming zhu Jianxing chen Xingkai wang Key Laboratory of Deep Earth Science and Engineering Ministry of EducationSichuan UniversityChengdu610065China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221116China Failure Mechanics and Engineering Disaster Prevention and Mitigation Key Laboratory of Sichuan ProvinceSichuan UniversityChengdu610065China Key Laboratory of Rock Mechanics and Geohazards of Zhejiang Province Shaoxing UniversityShaoxing312000China

Cracked straight-through Brazilian disc(CSTBD) samples prepared using two rock materials were used for thermal treatment from room temperature to 700℃. Uniaxial splitting experiments were performed using an automatic electro-hydraulic servo press to study the evolution laws of physical and fracture properties of different deep rock materials under high-temperature geological conditions. The fracture characteristics were measured using an industrial camera and digital image correlation technology to analyze the effect of high temperature on fracture properties and failure modes of the CSTBD samples after different thermal treatments. The micro-damage properties of green sandstone and granite materials were obtained using a scanning electron microscope(SEM). The following conclusions were drawn from the test results:(1) With the increasing temperature, the fracture characteristics of green sandstone and granite change from brittle fracture to plasticity fracture, the longitudinal wave velocity of granite decreases sharply at 600℃, and the damage factor reaches 0.8748 at 700℃.(2) The fracture toughness of green sandstone and granite decreases with increasing temperature;however, the decreasing range of granite is larger than that of green sandstone.(3) As the temperature increases, the fracture morphologies of green sandstone and granite materials become rougher, whereas thermal damage cracks of granite and intergranular fractures inside sandstone as well as pores of sandstone increase.(4) The crack tip opening displacement and peak strain corresponding to peak load increase with the temperature.

关键词： High temperature Cracked straight-through Brazilian disc(CSTBD)sample Fracture toughnessm Scanning electron microscope(SEM)

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miR-23a/b suppress cGAS-mediated innate and autoimmunity

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Cellular & Molecular Immunology 2021年第5期18卷 1235-1248页

作者： Qiuya yu lei Chu Yongxing Li Quanyi wang Juanjuan zhu chen wang Shufang Cui State Key Laboratory of Natural Medicines School of Life Science and TechnologyChina Pharmaceutical UniversityNanjingChina

Cyclic GMP-AMP synthase(cGAS),a key sensor of intracellular DNA,is essential for eliciting innate immunity against infection,whereas aberrant activation of cGAS by endogenous DNA promotes severe autoimmune ***,it is largely unknown how cGAS expression is regulated during pathogen infection and ***,we report that during herpes simplex virus type 1(HSV-1)infection,two microRNAs(miR-23a and miR-23b)whose levels significantly decrease due to their interaction with the lncRNA Oasl2-209 directly regulate the expression of *** of miR-23a/b markedly dampens cytosolic DNA-induced innate immune responses,whereas inhibition of miR-23a/b enhances these *** treated with miR-23a/b agomirs exhibit increased susceptibility to HSV-1 ***,cGAS is significantly upregulated in the Trex1^(−/−)mouse autoimmune disease *** of miR-23a/b blunts self DNA-induced autoinflammatory responses in Trex1^(−/−)***,our study not only reveals a novel regulatory mechanism of cGAS expression by miRNAs but also identifies a potential therapy for cGAS-related autoimmune diseases.

关键词： cGAS miR-23a miR-23b DNA virus Innate immunity Autoimmune disease

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Boosting thermal stability and crystallization of closed-loop-recyclable biodegradable poly(p-dioxanone) by end-group regulation

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Science China Chemistry 2024年第2期67卷 642-651页

作者： Jin lei zhu-Xin Gui Wan-Ting Xiong Gang Wu Si-Chong chen yu-Zhong wang The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu610064China

A chemically closed-loop-recyclable biodegradable polymer,poly(p-dioxanone)(PPDO),is one of the ideal candidates for single-use plastic products due to its suitability for different application ***,when PPDO wastes can be collected,its monomer p-dioxanone(PDO) will be obtained through chemical recycling of these wastes;when cannot be collected,the wastes are able to be biodegraded into harmless ***,unsatisfied thermal stability and low crystallization rate of PPDO restrict its wider ***,based on end-group regulation,we simultaneously realized the significant enhancement of thermal stability and crystallization of PPDO through the simple melt processing with tributyl phosphite(TBP) or triphenyl phosphite(TPP).The model reactions were conducted to investigate the reaction mechanism and theoretical products during the preparation of PPDO/phosphite *** kinds of phosphites were proved to act as the end-capped reagent and chain extender in the melt processing,while TBP presented better *** a result,the activation energy of thermal decomposition was largely elevated,and the unprecedented T_(5%)(the temperature at a weight loss of 5%) and Tmax(the temperature at a maximum rate of weight loss) of PPDO were obtained,i.e.,T_(5%)of ~330 ℃ and Tmaxof ~385 ℃ in N_(2) atmosphere,T_(5%)of ~240 ℃ and Tmaxof ~317 ℃ in air atmosphere,***,the increased crystallization rate,crystallinity,crystalline orderliness,and realizable monomer recovery(yield >90%,purity >99.9%) of PPDO/phosphite compounds were confirmed.

关键词： poly(p-dioxanone) phosphite thermal stability crystallization end-group regulation

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Using diffusive gradients in thin films technique for in-situ measurement of labile phosphorus around Oryza sativa L. roots in flooded paddy soils

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Pedosphere 2021年第1期31卷 76-82页

作者： yu wang Hao chen lei wang Wenbin zhu Jiahui yuAN Deb P.JAISI Xu ZHAO Shenqiang wang State Key Laboratory of Soil and Sustainable Agriculture Changshu National Agro-Ecosystem Observation and Research StationInstitute of Soil ScienceChinese Academy of SciencesNanjing 210008China Organic Food Development Center Nanjing Institute of Environmental SciencesMinistry of Environmental ProtectionNanjing 210042China Department of Plant and Soil Sciences University of DelawareNewark DE 19716(USA)

Behavior of phosphorus(P) in flooded rice soil is controlled by iron(Fe) redox cycling in root-zone. In this study, we applied a novel approach—the diffusive gradients in thin films(DGT) technique—for investigating the in-situ distribution of labile phosphorus(P) and Fe in close proximity to Asian rice(Oryza sativa L.) roots at submillimeter to millimeter spatial resolutions during the seedling and booting stages. We conducted a seven-year field experiment under rice-wheat rotation with different P fertilizer treatments. The results showed a significant and strong positive relationship of the average DGT-labile P concentration with soil Olsen P(R2= 0.77, P < 0.01) and with rice total P concentration(R^(2)= 0.62, P < 0.05). Furthermore, results on one-and two-dimensional changes of DGT-labile P indicated that fertilization only in the wheat season produced sufficient amounts of labile P in the flooded paddy soils, similar to when fertilizer was applied only in the rice season;dissolved P concentrations, however, were lower. A co-occurrence and significant positive correlation(P < 0.01) between DGT-labile P and Fe indicated Fe-coupled mobilization of P in flooded paddy soils. These results collectively indicated that the DGT technique provided information on in-situ distribution of labile P and its variability in close proximity to rice roots. This suggests that the DGT technique can improve our understanding of in-situ and high-resolution labile P processes in paddy soils and can provide useful information for optimizing P fertilization.

关键词： fertilization reduction labile P rice root Zr-oxide DGT Fe-P coupling

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Primary Sn-rich titianite in the Qitianling granite, Hunan Province, southern China: An important type of tin-bearing mineral and its implications for tin exploration

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Chinese Science Bulletin 2009年第5期54卷 798-805页

作者： XIE lei wang Rucheng chen Jun zhu JinChu ZHANG WenLan wang DeZi yu APeng State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University Nanjing210093 China

The Qitianling calc-alkaline granite in Hunan Province (South China) has attracted much attention since the discovery of the Furong super-large tin deposit. The present study provides new mineralogical data to address their implications for exploration of tin deposits. In the Taoxiwo granite in the southeastern part of the Qitianling granite body, Sn-rich titanite was identified as an important type of Sn-bearing mineral. The titanite commonly occurs with biotite as euhedral crystals, exhibiting typical envelope-like shape and sector-zoning texture. These indicate that the titanite most likely crystallized in the mag-matic stage. Electron-microprobe analyses show that the titanite is enriched in tin up to 1.12 wt% SnO2, with an average of 0.43 wt%. With the crystallization of the granite, primary minerals undertook hydro-thermal alteration by magma-derived fluids. Subsequently, in the hydrothermal stage, the primary Sn-bearing titanite was altered (at least partially), but still preserved its typical envelope-shaped outline. Micro-scale cassiterite is a representative product of such alteration; other secondary minerals include fluorite, ilmenite, Sn-bearing rutile and quartz. Therefore, the titanite, commonly present in the calc- alkaline granites, can be treated as an important Sn-carrying mineral in the Qitianling granite, reflecting the primary magmatic environment with tin enrichment. The hydrothermal alteration of the primary titanite and subsequent crystallization of cassiterite recorded a process of leaching and accumulation of tin in magmatic-hydrothermal evolution of the Snbearing granite. Thus, this titanite has important implications for tin exploration.

关键词：锡成因矿物学骑天岭花岗岩湖南

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DITCHES AND PONDS CAN BE THE SOURCES OR SINKS OF NON-POINT SOURCE POLLUTION:OBSERVATIONS IN AN UPLAND AREA IN THE JINGLINXI CATCHMENT,CHINA

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Frontiers of Agricultural Science and Engineering 2023年第4期10卷 607-626页

作者： Yiwen wang lei chen Kaihang zhu chenxi GUO yu PU ZhenyaoSHEN State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China.

As the common features of agroecosystems,ditches and ponds benefit the irrigation and drainage,as well as intercepting non-point source ***,most ditch-pond studies have been conducted in lowland *** test this source-sink assumption in upland areas,this study made observations on the ecological function of the ditch and pond system in a typical catchment in ***,the changes in ponds in the catchment were analyzed using high-resolution remote sensing ***,the migration of agricultural pollutants in ditches and ponds were analyzed by field sampling and laboratory *** results showed that over the past 15 years the length of ditches in the catchment and the number of small ponds(<500 m2)have increased by 32%and 75%,*** rate of change in nutrient concentrations in the ditches and ponds were mostly from-20%to 20%,indicating ditches and ponds can be both sources and sinks for agricultural ***,the contributing factors were explored and it was found that ditches and ponds are important sinks in dry ***,during the rainy season,ditches and ponds become sources of pollutants,with the rapid drainage of ditches and the overflow of ponds in upland *** results of this study revealed that the ditches and ponds could be used for ecological engineering in upland catchments to balance drainage and intercept pollutants.

关键词： ditches ponds non-point source pollution mountainous areas nitrogen phosphorus

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Accumulation characteristic of protein bodies in different regions of wheat endosperm under drought stress

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Journal of Integrative Agriculture 2016年第12期15卷 2921-2930页

作者： chen Xin-yu LI Bo SHAO Shan-shan wang lei-lei zhu Xiao-wei YANG yang wang Wen-jun yu Xu-run XIONG Fei Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops Yangzhou University Yangzhou 225009 P.R.China Jiangsu Yanjiang Institute of Agricultural Sciences Nantong 226541 P.R. China

The structural characteristics of protein body accumulation in different endosperm regions of hard wheat cultivar （XM33） and soft wheat cultivar （NM13） under drought stress were investigated. Drought stress treatment was implemented from plant regreening to the caryopsis mature stage. Microscope images of endosperm cells were obtained using resin semi- thin slice technology to observe the distribution and relative area of protein body （PB）. Compared with NM13, relative PB area of XM33 was significantly higher in sub-aleurone endosperm region. The amount of accumulation, including the size and relative area of PB, in two wheat cultivars was higher in sub-aleurone region than that in central region at 18 days post anthesis （DPA）. Drought stress significantly enhanced the sizes and relative areas of PBs in the dorsal and abdominal endosperms in two wheat cultivars. Particularly for dorsal endosperm, drought stress enhanced the relative PB area at 18 DPA and NM13 （5.0% vs. 6.73%） showed less enhancement than XM33 （5.49% vs. 8.96%）. However, NM13 （9.58% vs. 12.02%） showed greater enhancement than XM33 （10.25% vs. 11.7%） at 28 DPA. The protein content in the dorsal and abdominal endosperms of the two wheat cultivars decreased at 12 DPA and then increased until 38 DPA. Drought stress significantly increased the protein contents in the two main regions. From 12 to 38 DPA, the amount of PB accumulation and the protein content were higher in XM33 than those in NM13. The results revealed that PB distribution varied in different endosperm tissues and that the amount of PB accumulation was remarkably augmented by drought stress.

关键词： wheat protein bodies distribution accumulation drought stress

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Microbe-derived non-necrotic glycoside hydrolase family 12 proteins act as immunogenic signatures triggering plant defenses

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Journal of Integrative Plant Biology 2022年第10期64卷 1966-1978页

作者： Lan wang Hanmei Liu Mingmei Zhang yu Ye lei wang Jinyi zhu Zhaodan chen Xiaobo Zheng Yan wang yuanchao wang Department of Plant Pathology Nanjing Agricultural UniversityNanjing 210095China Key Laboratory of Soybean Disease and Pest Control(Ministry of Agriculture and Rural Affairs) Nanjing Agricultural University210095NanjingChina The Key Laboratory of Plant Immunity Nanjing Agricultural UniversityNanjing 210095China

Plant pattern recognition receptors(PRRs)are sentinels at the cell surface sensing microbial invasion and activating innate immune *** infection,certain microbial apoplastic effectors can be recognized by plant PRRs,culminating in immune responses accompanied by cell ***,the intricated relationships between the activation of immune responses and cell death are ***,we studied the glycoside hydrolase family12(GH12)protein,Ps109281,secreted by Phytophthora sojae into the plant apoplast during ***109281 exhibits xyloglucanase activity,and promotes *** infection in a manner dependent on the enzyme ***109281 is recognized by the membranelocalized receptor-like protein RXEG1 and triggers immune responses in various plant *** other characterized GH12 members,Ps109281 fails to trigger cell death in *** loss of cell death induction activity is closely linked to a sequence polymorphism at the *** sequence polymorphism does not affect the in planta interaction of Ps109281 with the recognition receptor RXEG1,indicating that cell death and immune response activation are determined using different regions of the GH12 *** GH12 protein also exists in other Phytophthora and fungal *** together,these results unravel the evolution of effector sequences underpinning different immune outputs.

关键词： apoplastic effector cell death glycoside hydrolases immune recognition immune responses

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