This paper explores the existence of heteroclinic cycles and corresponding chaotic dynamics in a class of 3-dimensional two-zone piecewise affine systems. Moreover, the heteroclinic cycles connect two saddle foci and ...This paper explores the existence of heteroclinic cycles and corresponding chaotic dynamics in a class of 3-dimensional two-zone piecewise affine systems. Moreover, the heteroclinic cycles connect two saddle foci and intersect the switching manifold at two points and the switching manifold is composed of two perpendicular planes.展开更多
Stormwater runoff from three types of urban surfaces, a parking lot, a street, and a building roof, was monitored during four rainfall events that occurred in the one-year period from June 2009 to June 2010. The event...Stormwater runoff from three types of urban surfaces, a parking lot, a street, and a building roof, was monitored during four rainfall events that occurred in the one-year period from June 2009 to June 2010. The event mean concentrations （EMC） of dissolved copper （Cu）, lead （Pb）, zinc （Zn）, manganese （Mn）, and iron （Fe） exceeded China＇s National Water Quality Standards for Surface Water. The degree of heavy metal contamination was related to the type of underlying surfaces. Additionally, the concentration of dissolved heavy metals peaked shortly after the runoff began and then declined sharply as a result of adequate flushing. First flush effects of varying degrees were also observed during all of the monitored rainfall events based on the first flush ratio （FF25）. Redundancy analysis revealed that four environmental variables （rain- fall depth, intensity, antecedent dry weather period and type of underlying surface） had significant effects on the strengths of the first flush effects, accounting for 72.9% of the variation in the FF25. Dissolved metals presented varying first flush effects on different underlying surfaces that occurred in the following relative order： parking lot 〉 roof〉 road for low intensity and high runoff volume rainfall events; parking lot 〉 road 〉 roof for high intensity and low runoff volume events. The relative strength of the first flush for dissolved heavy metals was Fe, Mn 〉 Cu, Zn 〉 Pb.展开更多
In the past studies,it is shown that cardiac troponin I(cTnI,encoded by TNNI3),as a cytoplasmic protein,is an inhibitory subunit in troponin complex,and involves in cardiomyocyte diastolic regulation.Here,we assessed ...In the past studies,it is shown that cardiac troponin I(cTnI,encoded by TNNI3),as a cytoplasmic protein,is an inhibitory subunit in troponin complex,and involves in cardiomyocyte diastolic regulation.Here,we assessed a novel role of cTnI as a nucleoprotein.Firstly,the nuclear translocation of cTnI was found in mouse,human fetuses and rat heart tissues.In addition,there were differences in percentage of intranuclear cTnI in different conditions.Based on weighted gene co-expression network analyses(WGCNA)and verification in cell experiments,a strong expression correlation was found between TNNI3 and Atp2a2,which encodes sarco-endoplasmic reticulum Ca2t ATPase isoform 2a(SERCA2a),and involves in ATP hydrolysis and Ca2t transient.TNNI3 gain and loss caused Atpa2a2 increase/decrease in a dosedependent manner both in mRNA and protein levels,in vivo and in vitro.By using ChIP-sequence we demonstrated specific binding DNA sequences of cTnI were enriched in ATP2a2 promoter239we889 region and the specific binding sequence motif of cTnI was analyzed by software as"CCAT",which has been reported to be required for YY1 binding to the promoter region of YY1-related genes.Moreover,it was further verified that pcDNA3.1()-TNNI3 could express cTnI proteins and increase the promoter activity of Atp2a2 through luciferase report assay.In the end,we evaluated beat frequencies,total ATP contents,Ca2t transients in TNNI3-siRNA myocardial cells.These findings indicated,for the first time,cTnI may regulate Atp2a2 in cardiomyocytes as a co-regulatory factor and participate in the regulation of intracellular Ca ions.展开更多
Precipitation is a key factor in the water cycle.At the same time,precipitation is the focus of study in meteorology and climatology,ecological environmental assessment,non-point source pollution and so on.Understandi...Precipitation is a key factor in the water cycle.At the same time,precipitation is the focus of study in meteorology and climatology,ecological environmental assessment,non-point source pollution and so on.Understanding the temporal-spatial variation and the corresponding factors of precipitation has become the object of hydrology and environmentology.Based on the annual precipitation data,we analyzed the spatial distribution of precipitation in Sichuan Province in China as well as the temporal-spatial variation and the corresponding influence factors involved.The results show that the amount of precipitation was abundant,but the spatial distribution was not consistent with it and the amount of precipitation gradually declined from the south-east to the north-west in Sichuan Province,China.Moreover,the spatial distribution was different throughout the years.The result of correlation analysis indicated that elevation,temperature and air pressure were three key factors affecting the amount and distribution of precipitation,and the correlation coefficients were 20.56,0.38 and 0.45 respectively.Notably,the relationship between the slope of topography and precipitation were significantly negative and the average correlation coefficient was 20.28.展开更多
文摘This paper explores the existence of heteroclinic cycles and corresponding chaotic dynamics in a class of 3-dimensional two-zone piecewise affine systems. Moreover, the heteroclinic cycles connect two saddle foci and intersect the switching manifold at two points and the switching manifold is composed of two perpendicular planes.
文摘Stormwater runoff from three types of urban surfaces, a parking lot, a street, and a building roof, was monitored during four rainfall events that occurred in the one-year period from June 2009 to June 2010. The event mean concentrations （EMC） of dissolved copper （Cu）, lead （Pb）, zinc （Zn）, manganese （Mn）, and iron （Fe） exceeded China＇s National Water Quality Standards for Surface Water. The degree of heavy metal contamination was related to the type of underlying surfaces. Additionally, the concentration of dissolved heavy metals peaked shortly after the runoff began and then declined sharply as a result of adequate flushing. First flush effects of varying degrees were also observed during all of the monitored rainfall events based on the first flush ratio （FF25）. Redundancy analysis revealed that four environmental variables （rain- fall depth, intensity, antecedent dry weather period and type of underlying surface） had significant effects on the strengths of the first flush effects, accounting for 72.9% of the variation in the FF25. Dissolved metals presented varying first flush effects on different underlying surfaces that occurred in the following relative order： parking lot 〉 roof〉 road for low intensity and high runoff volume rainfall events; parking lot 〉 road 〉 roof for high intensity and low runoff volume events. The relative strength of the first flush for dissolved heavy metals was Fe, Mn 〉 Cu, Zn 〉 Pb.
基金This study was supported by research grants from Natural Science Foundation of China(No.81700214,and 81670212).
文摘In the past studies,it is shown that cardiac troponin I(cTnI,encoded by TNNI3),as a cytoplasmic protein,is an inhibitory subunit in troponin complex,and involves in cardiomyocyte diastolic regulation.Here,we assessed a novel role of cTnI as a nucleoprotein.Firstly,the nuclear translocation of cTnI was found in mouse,human fetuses and rat heart tissues.In addition,there were differences in percentage of intranuclear cTnI in different conditions.Based on weighted gene co-expression network analyses(WGCNA)and verification in cell experiments,a strong expression correlation was found between TNNI3 and Atp2a2,which encodes sarco-endoplasmic reticulum Ca2t ATPase isoform 2a(SERCA2a),and involves in ATP hydrolysis and Ca2t transient.TNNI3 gain and loss caused Atpa2a2 increase/decrease in a dosedependent manner both in mRNA and protein levels,in vivo and in vitro.By using ChIP-sequence we demonstrated specific binding DNA sequences of cTnI were enriched in ATP2a2 promoter239we889 region and the specific binding sequence motif of cTnI was analyzed by software as"CCAT",which has been reported to be required for YY1 binding to the promoter region of YY1-related genes.Moreover,it was further verified that pcDNA3.1()-TNNI3 could express cTnI proteins and increase the promoter activity of Atp2a2 through luciferase report assay.In the end,we evaluated beat frequencies,total ATP contents,Ca2t transients in TNNI3-siRNA myocardial cells.These findings indicated,for the first time,cTnI may regulate Atp2a2 in cardiomyocytes as a co-regulatory factor and participate in the regulation of intracellular Ca ions.
基金supported by the National Basic Research Program of China (No.2003CB415204).
文摘Precipitation is a key factor in the water cycle.At the same time,precipitation is the focus of study in meteorology and climatology,ecological environmental assessment,non-point source pollution and so on.Understanding the temporal-spatial variation and the corresponding factors of precipitation has become the object of hydrology and environmentology.Based on the annual precipitation data,we analyzed the spatial distribution of precipitation in Sichuan Province in China as well as the temporal-spatial variation and the corresponding influence factors involved.The results show that the amount of precipitation was abundant,but the spatial distribution was not consistent with it and the amount of precipitation gradually declined from the south-east to the north-west in Sichuan Province,China.Moreover,the spatial distribution was different throughout the years.The result of correlation analysis indicated that elevation,temperature and air pressure were three key factors affecting the amount and distribution of precipitation,and the correlation coefficients were 20.56,0.38 and 0.45 respectively.Notably,the relationship between the slope of topography and precipitation were significantly negative and the average correlation coefficient was 20.28.
