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New atom movement mechanism for tracking path on disordering AuCuI(A_8^(Au)A_4^(Cu)) compound 被引量:3
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作者 谢佑卿 彭红建 +2 位作者 刘心笔 李小波 聂耀庄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3221-3256,共36页
Taking experimental path on disordering AuCuI(AAuCu8A4)composed of A Au8 and ACu4 stem alloy genes as an example, three discoveries and a method were presented. The ability of Au Cu I(AAu Cu8 A4)to keep structure ... Taking experimental path on disordering AuCuI(AAuCu8A4)composed of A Au8 and ACu4 stem alloy genes as an example, three discoveries and a method were presented. The ability of Au Cu I(AAu Cu8 A4)to keep structure stabilization against changing temperature is attributed to the fact that the AAu8 and ACu4 potential well depths greatly surpass their vibration energies, which leads to the subequilibrium of experimental path. A new atom movement mechanism of AuCuI(AAuACu84)to change structure for suiting variation in temperature is the resonance activating-synchro alternating of alloy genes, which leads to heterogeneous and successive subequilibrium transitions. There exists jumping order degree, which leads to the existence of jumping Tj-temperature and an unexpected so-called "retro-effect" about jumping temperature retrograde shift to lower temperatures upon the increasing heating rate. A set of subequilibrium holographic network path charts were obtained by the experimental mixed enthalpy path method. 展开更多
关键词 INTERMETALLICS alloy gene order/disorder transformation resonance activating-synchro alternating mechanism thermodynamic properties equilibrium and subequilibrium holographic network path charts
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Design,Analysis,and Optimization of a CMOS Active Pixel Sensor 被引量:2
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作者 徐江涛 姚素英 +2 位作者 李斌桥 史再峰 高静 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第9期1548-1551,共4页
A three-transistor active pixel sensor and its double sampling readout circuit implemented by a switch capacitor amplifier are designed. The circuit is embedded in a 64 × 64 pixel array CMOS image sensor and succ... A three-transistor active pixel sensor and its double sampling readout circuit implemented by a switch capacitor amplifier are designed. The circuit is embedded in a 64 × 64 pixel array CMOS image sensor and success-fully taped out with a Chartered 0.35μm process. The pixel pitch is 8μm × 8μm with a fill factor of 57%, the photo-sensitivity is 0.8V/(lux · s) ,and the dynamic range is 50dB. Theoretical analysis and test results indicate that as the process is scaled down, a smaller pixel pitch reduces the sensitivity. A deep junction n-well/p-substrate photodiode with a reasonable fill factor and high sensitivity are more appropriate for submicron processes. 展开更多
关键词 CMOS image sensor active pixel sensor fill factor photo-response sensitivity
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STUDY ON THE METHOD OF CONSTRUCTING RATIONAL CUBIC CURVES AND CURVED SURFACE INCLUDING CONTROLLING PARAMETERS
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作者 孙兰凤 高天真 +1 位作者 梁艳书 陈健 《Transactions of Tianjin University》 EI CAS 1998年第1期31-36,共6页
By adopting the method of controlling parameters this paper describes the construction of various kinds of cubic curve segment and curved surface fragment with rational and non rational parameters, and discusses the ... By adopting the method of controlling parameters this paper describes the construction of various kinds of cubic curve segment and curved surface fragment with rational and non rational parameters, and discusses the relationship between controlling parameters, weighted factors and types, kinds and characteristics of curve segments and curved surface fragments. A mathematical method is provided for CAGD with abundant connotations, broad covering region, convenience, flexibility and direct simplicity. 展开更多
关键词 controlling parameter weighted factor rational and non rational curve segment curved surface fragment matrix of parametric coefficient
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Dynamics models of soil organic carbon 被引量:7
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作者 杨丽霞 潘剑君 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期323-330,共8页
As the largest pool of terrestrial organic carbon, soils interact strongly with atmosphere composition, climate, and land change. Soil organic carbon dynamics in ecosystem plays a great role in global carbon cycle and... As the largest pool of terrestrial organic carbon, soils interact strongly with atmosphere composition, climate, and land change. Soil organic carbon dynamics in ecosystem plays a great role in global carbon cycle and global change. With development of mathematical models that simulate changes in soil organic carbon, there have been considerable advances in understanding soil organic carbon dynamics. This paper mainly reviewed the composition of soil organic matter and its influenced factors, and recommended some soil organic matter models worldwide. Based on the analyses of the developed results at home and abroad, it is suggested that future soil organic matter models should be developed toward based-process models, and not always empirical ones. The models are able to reveal their interaction between soil carbon systems, climate and land cover by technique and methods of GIS (Geographical Information System) and RS (Remote Sensing). These models should be developed at a global scale, in dynamically describing the spatial and temporal changes of soil organic matter cycle. Meanwhile, the further researches on models should be strengthen for providing theory basis and foundation in making policy of green house gas emission in China. 展开更多
关键词 Soil carbon Soil organic carbon Dynamic model
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A Systematic Study of the Forbidden Pitch in the CD Through-Pitch Curve for Beyond 130nm
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作者 赵宇航 朱骏 曹永峰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第5期889-892,共4页
The forbidden pitch "dip" in the critical dimension (CD) through the pitch curve is a well-known optical proximity effect. The CD and CD process window near the "dip",usually found near a pitch range of 1.1 to 1... The forbidden pitch "dip" in the critical dimension (CD) through the pitch curve is a well-known optical proximity effect. The CD and CD process window near the "dip",usually found near a pitch range of 1.1 to 1.4 wavelength/ NA (numerical aperture),is smaller when compared with other pitches. This is caused by inadequate imaging contrast for an unequal line and space grating. Although this effect is relatively well-known, its relationship with typical process condition parameters,such as the effective image blur caused by the photo-acid diffusion during the post exposure bake or the aberration in the imaging lens, has not been systematically studied. In this paper, we will examine the correlation between the image blur and the effect on the CD, including the decrease in the CD value (the depth of the "dip") and the CD process window. We find that both the decrease in the CD value and the focus latitude near the forbidden pitch correlate very well with the effective Gaussian image blur. Longer effective diffusion length correlates well with a smaller process window and a deeper CD "dip". We conclude that the dip depth is very sensitive to the change in image contrast. 展开更多
关键词 forbidden pitch effective resist diffusion length OPC OAI deep-UV
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Elastoplastic response of functionally graded cemented carbides due to thermal loading
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作者 黄自谦 李传新 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期463-466,共4页
Finite dement formulations are used to simulate the evolution of the elastoplastic response of functionally graded cemented carbides (FGCC) due to thermal loading. The geometry of specimens is an axisymmetric solid ... Finite dement formulations are used to simulate the evolution of the elastoplastic response of functionally graded cemented carbides (FGCC) due to thermal loading. The geometry of specimens is an axisymmetric solid cylinder with a two-dimensional gradient. The elastoplastic constitutive relationship is developed by constraint factors. Numerical results show that compressive stresses occur in the surface zone and tensile stresses in the cobalt rich zone when the temperature drops from the initial stress-free temperature of 800 to 0℃. The maximum value of the surface compressive stress is 254 MPa and the maximum value of the tensile stress is 252 MPa in the cobalt rich zones. When the cobalt concentration difference in the specimens is equal to or greater than 0.3, there is pronounced plastic flow in cobalt rich zone. When the temperature heats up from 0 to 800 ℃, the total plastic strain reaches 0.001 4. Plastic flow has a significant effect on the reduction of thermal stress concentration. 展开更多
关键词 functionally graded cemented carbides finite element method constraint factors elastoplastic response
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Available Contents of Trace Nutrient Element and Factors Affecting Their Availability in Western Jilin 被引量:4
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作者 施宪 王冬艳 +2 位作者 李月芬 靳克 郭珍 《Agricultural Science & Technology》 CAS 2010年第5期73-76,共4页
Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient ele... Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient elements and their affecting factors are studied. The results show that the available B in western Jilin is in a middle level,the content in Nong'an is higher than that in the others; the available Mn is extremely abundant; the available Cu in Nong'an is obviously higher than other areas,and the content in Da'an differs greatly; the available Zn is in a middle level; the severe shortage of available Mo differs between different areas; and the available Fe is extremely abundant. The available Mn,Cu and Fe have significantly positive correlation with their total content; the available B has significantly positive correlation with pH,and Zn has obviously negative correlation with pH; the available Mn and Fe had significantly positive correlation with soil organic matter. 展开更多
关键词 Trace nutrient element Available content The affecting factors Western Jilin
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Existence of homologous sequences corresponding to cDNA of the ver gene in diverse higher plant species 被引量:3
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作者 JiaSH YngWD 《Cell Research》 SCIE CAS CSCD 2001年第4期265-271,共7页
The presence of DNA homologues corresponding to verc203 (vernalization-related cDNA clone) was investigated by molecular hybridization techniques. The genes were detected in 16 plant species that cover 12 subclasses o... The presence of DNA homologues corresponding to verc203 (vernalization-related cDNA clone) was investigated by molecular hybridization techniques. The genes were detected in 16 plant species that cover 12 subclasses of the Takhtajan system of angiosperms classification including diverse model species. The results of Southern blot analysis showed a low copy number of this gene existed in rice, wheat, barley and Arabidopsis. The hybridization result of PCR products demonstrated the conservation of the gene corresponding to ver203 in diverse plants. The phylogenetic tree of the ver203 gene in tested plants was supported by evolution relationship of species. The ver203 gene expressed in a vernalized plumule winter wheat, instead of the root. And the endosperm before the treatment was essential for the ver203 expression during vernalization in wheat. In Arabidopsis thaliana, the pattern of expression showed that the gene corresponding to ver203 was expressed at low temperature for 14 days. Gibberellin(GA3) may accelerate the expression of ver203 gene in Arabidopsis exposed to low temperature. However, it could not replace vernalization treatment to initiate the gene expression. 展开更多
关键词 Ver203 gene vernalization-related gene flower initiation homologous DNA Takhtajan system.
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MEKK1, MKK1/MKK2 and MPK4 function together in a mitogen-activated protein kinase cascade to regulate innate immunity in plants 被引量:39
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作者 Minghui Gao Jinman Liu +3 位作者 Dongling Bi Zhibin Zhang Fang Cheng2, Sanfeng Chen Yuelin Zhang 《Cell Research》 SCIE CAS CSCD 2008年第12期1190-1198,共9页
Mitogen-activated protein kinase (MAPK) cascades play important roles in regulating plant innate immune responses. In a genetic screen to search for mutants with constitutive defense responses, we identified multipl... Mitogen-activated protein kinase (MAPK) cascades play important roles in regulating plant innate immune responses. In a genetic screen to search for mutants with constitutive defense responses, we identified multiple alleles of mpk4 and mekkl that exhibit cell death and constitutive defense responses. Bimolecular fluorescence complemen- tation (BiFC) analysis showed that both MPK4 and MEKK1 interact with MKK1 and MKK2, two closely related MAPK kinases, mkkl and mkk2 single mutant plants do not have obvious mutant phenotypes. To test whether MKK1 and MKK2 function redundantly, mkkl mkk2 double mutants were generated. The mkkl mkk2 double mutant plants die at seedling stage and the seedling-lethality phenotype is temperature-dependent. Similar to the mpk4 and mekkl mutants, the mkkl mkk2 double mutant seedlings accumulate high levels of H202, display spontaneous cell death, constitutively express Pathogenesis Related (PR) genes and exhibit pathogen resistance. In addition, activation of MPK4 by fig22 is impaired in the mkkl mkk2 double mutants, suggesting that MKK1 and MKK2 function together with MPK4 and MEKK1 in a MAP kinase cascade to negatively regulate innate immune responses in plants. 展开更多
关键词 MAPK innate immunity MPK4 MEKK1 MKK1 MKK2
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Finite element simulation of stress intensity factors in elastic-plastic crack growth 被引量:3
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作者 ALSHOAIBI Abdulnaser M ARIFFIN Ahmad Kamal 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第8期1336-1342,共7页
A finite element program developed elastic-plastic crack propagation simulation using Fortran language. At each propagation step, the adaptive mesh is automatically refined based on a posteriori h-type refinement usin... A finite element program developed elastic-plastic crack propagation simulation using Fortran language. At each propagation step, the adaptive mesh is automatically refined based on a posteriori h-type refinement using norm stress error estimator. A rosette of quarter-point elements is then constructed around the crack tip to facilitate the prediction of crack growth based on the maximum normal stress criterion and to calculate stress intensity factors under plane stress and plane strain conditions. Crack was modelled to propagate through the inter-element in the mesh. Some examples are presented to show the results of the implementation. 展开更多
关键词 Crack propagation Nodal displacement Stress intensity factor Adaptive mesh Finite element method (FEM)
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Helicobacter pylori vac A genotype is a predominant determinant of immune response to Helicobacter pylori CagA 被引量:12
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作者 Alexander Link Cosima Langner +9 位作者 Wiebke Schirrmeister Wiebke Habendorf Jochen Weigt Marino Venerito Ina Tammer Dirk Schlüter Philipp Schlaermann Thomas F Meyer Thomas Wex Peter Malfertheiner 《World Journal of Gastroenterology》 SCIE CAS 2017年第26期4712-4723,共12页
To evaluate the frequency of Helicobacter pylori (H. pylori) CagA antibodies in H. pylori infected subjects and to identify potential histopathological and bacterial factors related to H. pylori CagA-immune response. ... To evaluate the frequency of Helicobacter pylori (H. pylori) CagA antibodies in H. pylori infected subjects and to identify potential histopathological and bacterial factors related to H. pylori CagA-immune response. METHODSSystematic data to H. pylori isolates, blood samples, gastric biopsies for histological and molecular analyses were available from 99 prospectively recruited subjects. Serological profile (anti-H. pylori, anti-CagA) was correlated with H. pylori isolates (cagA, EPIYA, vacA s/m genotype), histology (Sydney classification) and mucosal interleukin-8 (IL-8) mRNA and protein expression. Selected H. pylori strains were assessed for H. pylori CagA protein expression and IL-8 induction in co-cultivation model with AGS cells. RESULTSThirty point three percent of microbiologically confirmed H. pylori infected patients were seropositive for CagA. Majority of H. pylori isolates were cagA gene positive (93.9%) with following vacA polymorphisms: 42.4% vacA s1m1, 23.2% s1m2 and 34.3% s2m2. Anti-CagA-IgG seropositivity was strongly associated with atrophic gastritis, increased mucosal inflammation according to the Sydney score, IL-8 and cagA mRNA expression. VacA s and m polymorphisms were the major determinants for positive (vacA s1m1) or negative (vacA s2m2) anti-CagA serological immune response, which also correlated with the in vitro inflammatory potential in AGS cells. In vitro co-cultivation of representative H. pylori strains with AGS cells confirmed functional CagA translocation, which showed only partial correlation with CagA seropositivity in patients, supporting vacA as major co-determinant of the immune response. CONCLUSIONSerological immune response to H. pylori cagA+ strain in H. pylori infected patients is strongly associated with vacA polymorphism, suggesting the crucial role of bacterial factors in immune and clinical phenotype of the infection. 展开更多
关键词 Helicobacter pylori SEROPOSITIVITY Virulence factors CAGA VACA Immune response
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Genetic Data Clustering Based on Minimum Coding Length
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作者 汪雪红 焦清局 +1 位作者 常盼盼 黄继风 《Agricultural Science & Technology》 CAS 2012年第6期1376-1380,共5页
[Objective] This paper aimed to provide a new method for genetic data clustering by analyzing the clustering effect of genetic data clustering algorithm based on the minimum coding length. [Method] The genetic data cl... [Objective] This paper aimed to provide a new method for genetic data clustering by analyzing the clustering effect of genetic data clustering algorithm based on the minimum coding length. [Method] The genetic data clustering was regarded as high dimensional mixed data clustering. After preprocessing genetic data, the dimensions of the genetic data were reduced by principal component analysis, when genetic data presented Gaussian-like distribution. This distribution of genetic data could be clustered effectively through lossy data compression, which clustered the genes based on a simple clustering algorithm. This algorithm could achieve its best clustering result when the length of the codes of encoding clustered genes reached its minimum value. This algorithm and the traditional clustering algorithms were used to do the genetic data clustering of yeast and Arabidopsis, and the effectiveness of the algorithm was verified through genetic clustering internal evaluation and function evaluation. [Result] The clustering effect of the new algorithm in this study was superior to traditional clustering algorithms, and it also avoided the problems of subjective determination of clustering data and sensitiveness to initial clustering center. [Conclusion] This study provides a new clustering method for the genetic data clustering. 展开更多
关键词 Genetic clustering Lossy compression Gaussian distribution Minimum coding length
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The mitochondrial genomes of Macrocheraia grandis grandis and Myrmoplasta mira(Hemiptera:Heteroptera:Pentatomomorpha) and the unique mitogenome rearrangement in Pyrrhocoroidea 被引量:1
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作者 Yu MEN Fei YE +1 位作者 Yanhui WANG Qiang XIE 《Entomotaxonomia》 CSCD 2019年第2期96-113,共18页
Sequencing technology has developed rapidly in recent years. Complete or nearly complete mitochondrial genomes(mitogenomes) of 155 species from 47 families in Heteroptera have been sequenced. However, the amounts of m... Sequencing technology has developed rapidly in recent years. Complete or nearly complete mitochondrial genomes(mitogenomes) of 155 species from 47 families in Heteroptera have been sequenced. However, the amounts of mitogenomes between those families are unbalanced, which makes it difficult to correctly discern the patterns of mitogenome rearrangement in Heteroptera. Among 21 species from ten families, ten variations in mitogenome rearrangement had been previously reported, among which the translocation between tRNA-Thr and tRNA-Pro was considered as a synapomorphy of Pyrrhocoroidea based on two mitogenomes. As only one mitogenome in each of Largidae and Pyrrhocoridae had been sequenced to conclude the synapomorphy, more mitogenomes of Pyrrhocoroidea need to be explored. In this study, additional two mitogenomes of Pyrrhocoroidea(Macrocheraia grandis grandis(Gray, 1832) and Myrmoplasta mira Gerst-cker, 1892) were sequenced. Both of them also possess the same translocation between tRNA-Thr and tRNA-Pro, which reaffirms that this kind of rearrangement is a molecular synapomorphy of Pyrrhocoroidea. Moreover, we discovered a more complex rearrangement in Myrmoplasta mira, in which six nearly identical duplications of tRNA-Thr were found located downstream of tRNA-Pro. Considering the high biodiversity of Heteroptera, more mitogenomic studies are needed to improve our knowledge about mitogenome rearrangements and the potential synapomorphies. 展开更多
关键词 Pyrrhocoroidea MITOGENOME synapomorphy PHYLOGENOMICS evolutionary history
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Comparison of Mode Quality Factors for Equilateral Triangular, Square and Rhombus Optical Micro-Resonators
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作者 黄永箴 国伟华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第2期117-120,共4页
The mode frequencies and the quality factors for the equilateral triangular resonator (ETR), the square resonator (SR) and the rhombus resonator (RR) are numerically calculated by the finite difference time domai... The mode frequencies and the quality factors for the equilateral triangular resonator (ETR), the square resonator (SR) and the rhombus resonator (RR) are numerically calculated by the finite difference time domain technique and the Padé approximation. The numerical results show that the resonant modes confined in an equilateral triangular cavity have much higher quality factors than those in the square or the rhombus cavities. The modes in the ETR are totally confined in transverse direction while those in the SR and RR are only partly confined. For the ETR with the side length of 4μm and the refractive index of 3 2, the mode quality factor of about 5 5×10 3 at the wavelength of 1 55μm has been obtained. 展开更多
关键词 MICRORESONATOR quality factor resonant frequency finite difference time domain technique semiconductor laser
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Diffusion and Reaction Model of Catalyst Pellets for Fischer-Tropsch Synthesis 被引量:1
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作者 Wu Jianmin Sun Qiwen +1 位作者 Zhang Zongsen Pang Lifeng 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第4期77-86,共10页
The diffusion and reaction phenomenon in a Fe-based catalyst pellet for Fischer-Tropsch synthesis was studied. It was considered that the pores of catalyst pellets were full of liquid wax under Fischer-Tropsch synthes... The diffusion and reaction phenomenon in a Fe-based catalyst pellet for Fischer-Tropsch synthesis was studied. It was considered that the pores of catalyst pellets were full of liquid wax under Fischer-Tropsch synthesis conditions. The re- actants diffused from the bulk gas phase to the external surface of the pellet, and then the reactants diffused through the wax inside the pellet and reacted on the internal surface formed along the pore passages of the pellet. On the basis of reaction kinetics and double a-ASF product distribution model, a diffusion and reaction model of catalyst pellet was established. The effects of diffusion and reaction interaction in a catalyst pellet, the bulk temperature, the reaction pressure and the pellet size on the reactivity were further investigated. The relationship between the internal diffusion effectiveness factor of spherical catalyst pellet and the Thiele modulus were also discussed. The bulk temperature and pellet size have significant effects on the reactivity, while the pressure shows only a slight influence on the reactivity. The internal diffusion effectiveness factor decreases with an increasing Thiele modulus. 展开更多
关键词 Fischer-Tropsch synthesis diffusion and reaction catalyst pellet internal diffusion effectiveness factor
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Scale Effect of Climate and Soil Texture on Soil Organic Carbon in the Uplands of Northeast China 被引量:17
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作者 WANG Dan-Dan SHI Xue-Zheng +5 位作者 WANG Hong-Jie D. C. WEINDORF YU Dong-Sheng SUN Wei-Xia REN Hong-Yan ZHAO Yong-Cun 《Pedosphere》 SCIE CAS CSCD 2010年第4期525-535,共11页
Understanding how spatial scale influences commonly-observed effects of climate and soil texture on soil organic carbon (SOC) storage is important for accurately estimating the SOC pool at different scales. The rela... Understanding how spatial scale influences commonly-observed effects of climate and soil texture on soil organic carbon (SOC) storage is important for accurately estimating the SOC pool at different scales. The relationships among climate factors, soil texture and SOC density at the regional, provincial, city, and county scales were evaluated at both the soil surface (0-20 cm) and throughout the soil profile (0-100 cm) in the Northeast China uplands. We examined 1 022 profiles obtained from the Second National Soil Survey of China. The results indicated that the relationships between climate factors and SOC density generally weakened with decreasing spatial scale. The provincial scale was optimal to assess the relationship between climate factors and SOC density because regional differences among provinces were covered up at the regional scale. However, the relationship between soil texture and SOC density had no obvious trend with increasing scale and changed with temperature. There were great differences in the impacts of climate factors and soil texture on SOC density at different scales. Climate factors had a larger effect on SOC density than soil texture at the regional scale. Similar trends were seen in Heilongjiang and eastern Inner Mongolia at the provincial scale. But, soil texture had a greater effect on SOC density compared with climate factors in Jilin and Liaoning. At the city and county scales, the influence of soil texture on SOC density was more important than climate factors. 展开更多
关键词 FACTOR PRECIPITATION spatial scale temperature
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Increased expression of mitogen-activated protein kinase and its upstream regulating signal in human gastric cancer 被引量:16
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作者 BinLiang ShanWang +3 位作者 Xue-GuangZhu Yong-XiangYu Zhi-RongCui You-ZhiYu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第5期623-628,共6页
AIM: To investigate the expression of mitogen-activated protein kinases (MAPKs) and its upstream protein kinase in human gastric cancer and to evaluate the relationship between protein levels and clinicopathological p... AIM: To investigate the expression of mitogen-activated protein kinases (MAPKs) and its upstream protein kinase in human gastric cancer and to evaluate the relationship between protein levels and clinicopathological parameters. METHODS: Western blot was used to measure the expression of extracellular signal-regulated kinase (ERK)-1, ERK-2, ERK-3, p38 and mitogen or ERK activated protein kinaseMEK-1 proteins in surgically resected gastric carcinoma, adjacent normal mucosa and metastatic lymph nodes from 42 patients. Immunohistochemistry was employed for their localization. RESULTS: Compared with normal tissues, the protein levels of ERK-1 (integral optical density value 159 526?5 760 vs 122 807±65 515, P= 0.001), ERK-2 (168 471±95 051 vs 120 469±72 874, P<0.001), ERK-3 (118 651±71 513 vs 70 934±68 058,P<0.001), P38 (104 776±51 650 vs 82 930±40 392, P= 0.048) and MEK-1 (116 486±45 725 vs 101 434±49 387, P = 0.027) were increased in gastric cancer tissues. Overexpression of ERK-3 was correlated to TNM staging [average ratio of integral optic density (IOD)tumor: IODnormal in TNM I, II, III, IV tumors was 1.43±0.34, 5.08±3.74, 4.99±1.08, 1.44±1.02, n = 42, P= 0.023] and serosa invasion (4.31±4.34 vs 2.00±2.03, P = 0.037). In poorly differentiated cancers (n = 33), the protein levels of ERK-1 and ERK-2 in stage III and IV tumors were higher than those in stage I and II tumors (2.64+3.01 vs 1.01±0.33, P= 0.022; 2.05±1.54 vs1.24±0.40, P= 0.030). Gastric cancer tissues with either lymph node involvement (2.49±2.91 vs1.03±0.36, P= 0.023; 1.98±1.49vs1.24±0.44, P= 0.036) or serosa invasion (2.39±2.82 vs 1.01±0.35, P= 0.022; 1.95±1.44 vs1.14±0.36, P=0.015) expressed higher protein levels of ERK-1 and ERK-2. In Borrmann II tumors, expression of ERK-2 and ERK-3 was increased compared with Borrmann III tumors (2.57±1.86 vs1.23±0.60, P= 0.022; 5.50±5.05 vs1.83±1.21, P= 0.014). Borrmann IV tumors expressed higher p38 protein levels. No statistically significant difference in expression of MAPKs was found when stratified to tumor size or histological grade (P>0.05). Protein levels of ERK-2, ERK-3 and MEK-1 in metastatic lymph nodes were 2-7 folds higher than those in adjacent normal mucosa. The immunohistochemistry demonstrated that ERK-1, ERK-2, ERK-3, p38 and MEK-1 proteins were mainly localized in cytoplasm. The expression of MEK-1 in gastric cancer cells metastasized to lymph nodes was higher than that of the primary site. CONCLUSION: MAPKs, particularly ERK subclass are overexpressed in the majority of gastric cancers. Overexpression of ERKs is correlated to TNM staging, serosa invasion, and lymph node involvement. The overexpression of p38 most likely plays a prominent role in certain morphological subtypes of gastric cancers. MEK-1 is also overexpressed in gastric cancer, particularly in metastatic lymph nodes. Upregulation of MARK signal transduction pathways may play an important role in tumorigenesis and metastatic potential of gastric cancer. 展开更多
关键词 Gastric cancer Mitogen-activated protein kinase Extracellular signal-regulated kinase Signal transduction
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Estimation of Acentric Factor of Organic Compounds with Corresponding States Group Contribution Method 被引量:3
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作者 衣守志 贾原媛 马沛生 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第5期709-712,共4页
A new estimation method was proposed by combining the corresponding state principle with the group contribution method through introducing the concept of assumed-critical properties. Combining it with the Reidel equat... A new estimation method was proposed by combining the corresponding state principle with the group contribution method through introducing the concept of assumed-critical properties. Combining it with the Reidel equation, a new acentric factor correlation equation (CSGC-Reidel) was developed. Contribution values of 70 groups were obtained by correlating acentric factor data of 228 organic compounds of 14 type substances including saturated hydrocarbons, unsaturated hydrocarbons, cyclanes, aromatics, oxygen compounds, nitrogen compounds,halohydrocarbons, etc. The average error of acentric factor is 3.52% between the literature data and the predicated with the new estimation method. 展开更多
关键词 acentric factor estimation of properties corresponding state group contribution (CSGC) Edmister equation Reidel equation
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Computation of rolling resistance caused by rubber hysteresis of truck radial tire 被引量:1
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作者 MA Gai-ling XU Hong CUI Wen-yong 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第5期778-785,共8页
Applying the results of stress and strain calculated by 3D finite element model of truck radial tire 11.00R20, a MATLAB program used to compute rolling resistance of the tire caused by hysteresis rolling resistance (H... Applying the results of stress and strain calculated by 3D finite element model of truck radial tire 11.00R20, a MATLAB program used to compute rolling resistance of the tire caused by hysteresis rolling resistance (HRR) is worked out. The HRR distribution on different part of tire section, and the effects of speed, load, internal pressure and the width of the rim on HRR are analyzed. The analysis results showed that energy loss produced by tread rubber contributes the most part to HRR of the whole tire, and that to decrease the HRR, the hysteresis factor of the tread rubber should be reduced, and the distribution of the stress and strain on the section be optimized. 展开更多
关键词 Truck radial tire Hysteresis rolling resistance (HRR) Finite element analysis (FEA) Hysteresis factor Tire structuredesign
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Association between preoperative high sensitive troponin I levels and cardiovascular events after hip fracture surgery in the elderly 被引量:16
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作者 Bum Sung Kim Tae-Hoon Kim +5 位作者 Jeong-Hwan Oh Chang Hee Kwon Sung Hea Kim Hyun-Joong Kim Heung Kon Hwang Sang-Man Chung 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第3期215-221,共7页
Objective Cardiovascular complications contribute to postoperative morbidity and mortality in elderly hip fracture patients. Limited data are available regarding which preoperative risk factors predict cardiovascular ... Objective Cardiovascular complications contribute to postoperative morbidity and mortality in elderly hip fracture patients. Limited data are available regarding which preoperative risk factors predict cardiovascular course following hip fracture surgery (HFS). We used high sensitive troponin I (hs-TnI) assays and clinical parameters to identify preoperative risk factors associated with major adverse cardiac events (MACE) in elderly hip frac^u'e patients. Method From August 2014 to November 2016, 575 patients with hip fracture were enrolled in a retrospective, single-center registry. A total of 262 of these patients underwent HFS and hs-TnI assays. MACE was defined as postoperative all-cause deaths, heart failure (HF), new-onset atrial fibrillation (AF), myocardial infarction (MI) and cardiovascular re-hospitalization that occurred within 90 days postoperative. Results Of 262 HFS patients, MACE developed following HFS in 65 (24.8%). Patients with MACE were older and had higher rates of renal insufficiency, coronary artery disease, prior HF, low left ventricular ejection fraction and use of beta blockers; higher levels of hs-Tnl and N-terminal pro-brain natriuretic peptide (NT-proBNP) and higher revised cardiac risk index. A preoperative hs-TnI≥ 6.5 ng/L was associated with high risk of postoperative HF, new-onset AF and MACE. In multivariable analysis, pre-operative independent predictors for MACE were age 〉 80 years [adjusted hazard ratio (HR): 1.79, 95% confident interval (CI): 1.03-3.13, P = 0.04], left ventricular ejection fraction (LVEF) 〈 50% (adjusted HR: 3.17, 95% CI: 1.47-5.82, P 〈 0.01) and hs-TnI 〉 6.5 ng/L (adjusted HR: 3.75, 95% CI: 2.09~5.17, P 〈 0.01). Conclusion In elderly patients with hip fracture who undergo HFS, a preoperative assessment of hs-TnI may help the risk refinement of cardiovascular complications. 展开更多
关键词 Cardiovascular complication High sensitive troponin I Hip fracture surgery
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