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刘岳云的“西学中源”论及其构建的科学知识体系——《格物中法》初探 被引量:5
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作者 张明悟 《自然科学史研究》 CSCD 北大核心 2012年第2期152-166,共15页
《格物中法》是晚清"西学中源"说的一部集大成之作。作者刘岳云从中国古代典籍中搜集了大量有关科学及技术的记载和论述,把它们组织起来,建构了一套完整的中国式科学知识体系,从而论证"西学中源"说,并与西学一较短... 《格物中法》是晚清"西学中源"说的一部集大成之作。作者刘岳云从中国古代典籍中搜集了大量有关科学及技术的记载和论述,把它们组织起来,建构了一套完整的中国式科学知识体系,从而论证"西学中源"说,并与西学一较短长。文章分析了《格物中法》的选材和构架,并发掘其在中国科学史研究上的意义。 展开更多
关键词 《格物中法》 西学中源 刘岳云
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主敬立本与穷理之基——对朱子“格物致知补传”中“已知之理”的阐释 被引量:1
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作者 李健芸 《安徽大学学报(哲学社会科学版)》 CSSCI 北大核心 2021年第1期42-49,共8页
朱子在“格物致知补传”中提到的“已知之理”一直未获得足够的关注,但它却是理解朱子格物穷理思想的必要一环。已知之理首先是穷理之前的小学之教的内容,但究其实质,它是一种关于“理”的知识。“理”在朱子的界定中可以理解为事物依... 朱子在“格物致知补传”中提到的“已知之理”一直未获得足够的关注,但它却是理解朱子格物穷理思想的必要一环。已知之理首先是穷理之前的小学之教的内容,但究其实质,它是一种关于“理”的知识。“理”在朱子的界定中可以理解为事物依其自身的本然规定而应当遵循的当然之则,而已知之理就是一种对事事物物的当然之则的形式上的理解。但这种知只有在一种自主自觉的心灵状态中才能得到呈现,而这种心灵状态正是经由“主敬”工夫的清理而得到确立的。由此呈现的知识先于具体的穷理活动,并为穷理活动确定方向,即心灵探究以事事物物的当然之则为根本的方向。同时,这种知识根源于心灵自身之理,其为穷理活动确立了根基。当然,作为形式上的知,已知之理需要在具体展开的穷理活动中由具体理解的一事一物的当然之则加以充实,只有在具体的当然之则的知识的充实下,心灵对“理”的理解才是真实而丰富的。对已知之理的阐明表明,朱子的格物思想并非如同一些心学家所批评的那样支离和无头脑。 展开更多
关键词 朱子 已知之理 主敬 格物 穷理
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《格物粗谈》中的服饰类条目研究
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作者 王鑫 厚宇德 《服饰导刊》 2020年第1期41-45,共5页
[研究意义]《格物粗谈》一书专门设有“服饰”一节。其中包含衣物保存、纺织品性能改变、织品洗涤,以及香料和佩饰制作等方面的实用方法与经验,使该书成为对宋元时期这些领域做深入研究的重要文献资料。[研究方法]文章对书中这部分条目... [研究意义]《格物粗谈》一书专门设有“服饰”一节。其中包含衣物保存、纺织品性能改变、织品洗涤,以及香料和佩饰制作等方面的实用方法与经验,使该书成为对宋元时期这些领域做深入研究的重要文献资料。[研究方法]文章对书中这部分条目按内容予以分类,对这些经验方法做了科学解读。[研究结果与结论]研究发现与该书中其他类别知识往往真假并存不同,这部分内容在现代科学的语境下,基本上都是有可靠依据的,因而是真实可信的。这证明这些知识应该是直接来源于古人的生活实践,因而能较好地反映那一时期人们的部分生活状态。 展开更多
关键词 《格物粗谈》 服饰 洗涤
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“格物”之“格”考述
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作者 余沛壹 《现代语文》 2020年第8期15-19,共5页
从文字训诂的视角出发,以传世文献中对“格物”之“格”的主要训释为切入点,对“格”的字义进行考证。研究发现,“格物”之“格”可释为“来、至”“捍御”“穷、究”“正”“量、絜”等。不同思想流派对“格”的释义截然不同乃至针锋相... 从文字训诂的视角出发,以传世文献中对“格物”之“格”的主要训释为切入点,对“格”的字义进行考证。研究发现,“格物”之“格”可释为“来、至”“捍御”“穷、究”“正”“量、絜”等。不同思想流派对“格”的释义截然不同乃至针锋相对,这也是他们不同格物观念及学说体系的体现。 展开更多
关键词 格物 “格”字 训诂
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Wood Physical and Mechanical Properties of Populus × canadensis Moench and Populus ×euramericana(Dode) Guinier cv. Gelrica
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作者 张英杰 冯德君 窦延光 《Agricultural Science & Technology》 CAS 2017年第12期2532-2535,共4页
The physical-mechanical properties of Populus x canadensis Moench and Populus x euramericana (Dode) Guinier cv. Gelrica were studied to provide theoret- ical and scientific bases for the directional breeding and eff... The physical-mechanical properties of Populus x canadensis Moench and Populus x euramericana (Dode) Guinier cv. Gelrica were studied to provide theoret- ical and scientific bases for the directional breeding and efficient use of artificial forests with P. canadensis and P. euramericana Gelrica. The results showed the air-dried density, basic density of P. canadensis were 0.468 g/cm3 and 0.372 g/cm3, respectively; the shrinkage coefficient of radial, tangential and volume were 0.133%, 0.270% and 0.553%, respectively;the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain were 9 302.99 MPa, 79.69 MPa and 40.32 Mpa, respectively. As for the P. euramericana Gelrica, the air-dried density, basic densitywere 0.453 and 0.355 g/cm3, respectively; the shrink- age coefficient of radial, tangential and volume were 0.205%, 0.304% and 0.554%, respectively; the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain were 9 014.44, 55.87 and 33.09 Mpa respectively. Comprehensive analysis of the indicators showed that the properties of P. canadensis were better than those of P.euramericana Gelrica. 展开更多
关键词 Populus x canadensis Moench Populus x euramericana (Dode) Guiniercv. Ge/rica Physical properties Mechanical properties
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In vitro Dissolution and Pharmacokinetics in Beagle Dogs of a Self-Emulsifying Formulation of Tretinoin
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作者 全东琴 徐贵霞 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第2期105-109,共5页
Aim In vitro dissolution test and pharmacokinetics in beagle dogs wereconducted to assess the formulation of tretinoin in self-emulsifying systems. Methods Theconcentrations of tretinoin were determined by HPLC. A cro... Aim In vitro dissolution test and pharmacokinetics in beagle dogs wereconducted to assess the formulation of tretinoin in self-emulsifying systems. Methods Theconcentrations of tretinoin were determined by HPLC. A crossover study was performed in four fastingbeagle dogs with the formulation of self-emulsifying systems and commercial capsules. Results Theresults showed that the dissolution rate in 15 min of tretinoin in self-emulsifying systems washigher than 80% while that of the commercial capsules was lower than 5% . The area under the plasmaconcentration-time curve (AUC) of the self-emulsifying formulation was significantly higher andC_(max) was approximately two times greater than those of commercial capsule, respectively, Inaddition, the time taken to reach peak was shorter (2 h to 1.25 h) for self-emulsifying formulationof tretinoin. Conclusion The self-emulsifying drug delivery systems.can significantly increasetretinoin in vitro dissolution and in vivo absorption. 展开更多
关键词 self-emulsifying systems TRETINOIN BIOAVAILABILITY DISSOLUTION
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Alloy gene Gibbs energy partition function and equilibrium holographic network phase diagrams of AuCu_3-type sublattice system 被引量:3
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作者 谢佑卿 李小波 +2 位作者 刘心笔 聂耀庄 彭红建 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3585-3610,共26页
Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing exp... Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing experimental phenomena of alloy phase transitions during extremely slow variation in temperature by equilibrium thinking mode and then taking erroneous knowledge of experimental phenomena as selected information for establishing Gibbs energy function and so-called equilibrium phase diagram. Second, the equilibrium holographic network phase diagrams of AuCu3-type sublattice system may be used to describe systematic correlativity of the composition?temperature-dependent alloy gene arranging structures and complete thermodynamic properties, and to be a standard for studying experimental subequilibrium order-disorder transition. Third, the equilibrium transition of each alloy is a homogeneous single-phase rather than a heterogeneous two-phase, and there exists a single-phase boundary curve without two-phase region of the ordered and disordered phases; the composition and temperature of the top point on the phase-boundary curve are far away from the ones of the critical point of the AuCu3 compound. 展开更多
关键词 AuCu3 compound AuCu3-type sublattice system alloy gene Gibbs energy partition function equilibrium holographic network phase diagram systematic metal materials science
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Alloy gene Gibbs energy partition function and equilibrium holographic network phase diagrams of Au_3Cu-type sublattice system 被引量:3
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作者 谢佑卿 聂耀庄 +2 位作者 李小波 彭红建 刘心笔 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第1期211-240,共30页
Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that... Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that the Gibbs energy function of an alloy phase should be derived from Gibbs energy partition function constructed of alloy gene sequence and their Gibbs energy sequence. Second, the six rules for establishing alloy gene Gibbs energy partition function have been discovered, and it has been specially proved that the probabilities of structure units occupied at the Gibbs energy levels in the degeneracy factor for calculating configuration entropy should be degenerated as ones of component atoms occupied at the lattice points. Third, the main characteristics unexpected by today’s researchers are as follows. There exists a single-phase boundary curve without two-phase region coexisting by the ordered and disordered phases. The composition and temperature of the top point on the phase-boundary curve are far away from those of the critical point of the Au3Cu compound; At 0 K, the composition of the lowest point on the composition-dependent Gibbs energy curve is notably deviated from that of the Au3Cu compounds. The theoretical limit composition range of long range ordered Au3Cu-type alloys is determined by the first jumping order degree. 展开更多
关键词 Au3Cu compound Au3Cu-type sublattice system alloy gene Gibbs energy partition function equilibrium holographic network phase diagrams systematic metal materials science
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An Explicit Difference Scheme with High Accuracy and Branching Stability for Solving Parabolic Partial Differential Equation 被引量:4
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作者 马明书 王肖凤 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第4期98-103,共6页
This paper presents an explicit difference scheme with accuracy and branching stability for solving onedimensional parabolic type equation by the method of undetermined parameters and its truncation error is O(△t4+△... This paper presents an explicit difference scheme with accuracy and branching stability for solving onedimensional parabolic type equation by the method of undetermined parameters and its truncation error is O(△t4+△x4). The stability condition is r=a△t/△x2<1/2. 展开更多
关键词 parabolic type equation explicit difference scheme high accuracy branching stability truncation er
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Distribution pattern of rare plants along riparian zone in Shennongjia Area 被引量:4
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作者 江明喜 邓红兵 蔡庆华 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期25-27,83,共3页
Due to the importance of riparian zone in maintaining and protecting regional biodiversity, increasingly more ecologists paid their attentions to riparian zone and had been aware of the important effects of riparian z... Due to the importance of riparian zone in maintaining and protecting regional biodiversity, increasingly more ecologists paid their attentions to riparian zone and had been aware of the important effects of riparian zone in basic study and practical management. In this study, 42 sampling belts (10 m?00 m) parallel to the bank of Xiangxi River at different elevations in Shennongjia Area were selected to investigate the riparian vegetation and rare plants. 14 species of rare plants were found distributing in riparian zone, accounting for 42.4% of the total rare plant species in Shennongjia Area. The main distribution range of the 14 rare plant species was the evergreen and deciduous mixed broadleaved forest at elevation of 1200-1800 m, where, species diversity of plant community was the maximum at the moderate elevation. The analysis of TWINSPAN divided the 14 rare species into 3 groups against the elevation, namely low elevation species group, moderate elevation species group, and high elevation species group. The analysis of DCA ordination showed similar results to that of TWINSPAN. In the paper, the authors discussed the reasons forming the distribution pattern of rare plant species, and pointed out that the important function of riparian zone on rare plant species protection. 展开更多
关键词 Xiangxi River Rare plant Riparian zone Distribution pattern BIODIVERSITY
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Structure Determination of By-product in Grignard Reaction for Preparing Mifepristone Derivatives 被引量:1
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作者 陈安平 雷小平 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第1期19-23,共5页
Aim To determine the structure of the by-product produced in Grignard reaction for preparing mifepristone derivatives, and elucidate the reaction mechanism.Methods The structure of the by-product was determined with e... Aim To determine the structure of the by-product produced in Grignard reaction for preparing mifepristone derivatives, and elucidate the reaction mechanism.Methods The structure of the by-product was determined with elemental analysis, one- and two-dimension spectra NMR (DEPT, 1H-1Hcosy, HMQC, HMBC) and compared with those of mifepristone.Results The main by-product was 11,17-di-addition product of Grignard reagent of N, N-dimethylamino phenyl bromide.Conclusion This is the first complete assignment of 1H NMR and 13C NMR of compound (3). 展开更多
关键词 by-product identification mifepristone derivatives two-dimension NMR
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Microstructure and superhardness effect of VC/TiC superlattice films 被引量:1
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作者 董学超 岳建岭 +2 位作者 王恩青 李淼磊 李戈扬 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2581-2586,共6页
Vanadium carbide/titanium carbide (VC/TiC) superlattice films were synthesized by magnetron sputtering method. The effects of modulation period on the microstructure evolution and mechanical properties were investig... Vanadium carbide/titanium carbide (VC/TiC) superlattice films were synthesized by magnetron sputtering method. The effects of modulation period on the microstructure evolution and mechanical properties were investigated by EDXA, XRD, HRTEM and nano-indentation. The results reveal that the VC/TiC superlattice films form an epitaxial structure when their modulation period is less than a critical value, accompanied with a remarkable increase in hardness. Further increasing the modulation period, the hardness of superlattices decreases slowly to the rule-of-mixture value due to the destruction of epitaxial structures. The XRD results reveal that three-directional strains are generated in superlattices when the epitaxial structure is formed, which may change the modulus of constituent layers. This may explain the remarkable hardness enhancement of VC/TiC superlattices. 展开更多
关键词 superlattice films carbide films microstructure evolution superhardness effect epitaxial growth
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Dark Solitons in FPU Lattice Chain 被引量:2
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作者 WANG Deng-Long YANG Ru-Shu YANG You-Tian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5X期917-920,共4页
Based on multiple scales method, we study the nonlinear properties of a new Fermi-Pasta-Ulam lattice model analytically. It is found that the lattice chain exhibits a novel nonlinear elementary excitation, i.e. a dark... Based on multiple scales method, we study the nonlinear properties of a new Fermi-Pasta-Ulam lattice model analytically. It is found that the lattice chain exhibits a novel nonlinear elementary excitation, i.e. a dark soliton. Moreover, the modulation depth of dark soliton is increasing as the anharmonic parameter increases. 展开更多
关键词 FPU lattice chain a dark soliton the multiple-scale method
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Abnormality of Magnetic Behavior and Resistivity of La_(0.7-x)Dy_x Sr_(0.3)MnO_3 (0.00≤x≤0.30)System at Low Temperature
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作者 刘宁 徐素军 +1 位作者 童伟 严国清 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期173-177,共5页
By measuring M-T curves, ρ-T curves and MR-T curves of the samples under different temperatures, the influence of Dy doping (0.00 ≤ x ≤0.30) on the magnetic and electric properties of La0.7-xDyxSr0.3MnO3 has been... By measuring M-T curves, ρ-T curves and MR-T curves of the samples under different temperatures, the influence of Dy doping (0.00 ≤ x ≤0.30) on the magnetic and electric properties of La0.7-xDyxSr0.3MnO3 has been studied. The experimental results show that, with the increase of the Dy content, the system undergoes a transition from long range ferromagnetic order to the cluster-spin glass state and further to antiferromagnetic order. For the samples with x=0.20 and 0.30, their magnetic behaviors are abnormal at low temperature, and their resistivities at low temperature have a minimum value. These peculiar phenomena not only come from the lattice effect induced by doping, but also from extra magnetic coupling induced by doping. 展开更多
关键词 MANGANITE Abnormality of resistivity at low temperature Lattice effect Extra magnetic coupling
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Structure identification for compound I separated and purified from taxoids-produced endophytic fungi (Alternaria. alternata var. taxi 1011)
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作者 项勇 刘君 +1 位作者 呂安国 崔京霞 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期217-220,共4页
Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physio... Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physiological active com-pounds through microbial fermentation can give a new way to resolve resource limitation and to find out alternative source. Through the methods of organic solvent extraction, thin layer chromatography (TLC) and column chromatography, compound I was isolated, purified from the liquid fermentation metabolites of the taxoids-produced endophytic fungi (Alternaria. alternata var. taxi 1011 Y. Xiang et LU An-guo) that was screened from the bark of Taxus. cuspidata Sieb.et Zucc.. Compound I was identified as one kind of taxoids type III, based on the analyzing results by using the methods of ultraviolet spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR). This study provides a com-pleted method for separation and purification of the endophytic fungi as well as structure identification of its fermentation me-tabolite 展开更多
关键词 Alternaria. Alternata var. taxi 1011 TAXOIDS Separation Purification Structure identification
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A High-order Accuracy Explicit Difference Scheme with Branching Stability for Solving Higher-dimensional Heat-conduction Equation 被引量:3
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作者 MA Ming-shu MA Ju-yi +1 位作者 GU Shu-min ZHU Lin-lin 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期446-452,共7页
A high-order accuracy explicit difference scheme for solving 4-dimensional heatconduction equation is constructed. The stability condition is r = △t/△x^2 = △t/△y^2 = △t/△z^2 = △t/△w^2 〈 3/8, and the truncatio... A high-order accuracy explicit difference scheme for solving 4-dimensional heatconduction equation is constructed. The stability condition is r = △t/△x^2 = △t/△y^2 = △t/△z^2 = △t/△w^2 〈 3/8, and the truncation error is O(△t^2 + △x^4). 展开更多
关键词 heat-conduction equation explicit difference scheme high-order accuracy branching stability
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Clopidogrel resistance response in patients with coronary artery disease and metabolic syndrome: the role of hyperglycemia and obesity 被引量:21
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作者 Zhao-Ke WU Jing-Jing WANG +4 位作者 Ting WANG Shen-Shen ZHU Xi-Ling CHEN Chao LIU Wei-Guo ZHANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2015年第4期378-382,共5页
Background Despite the proven benefits of clopidogrel combined aspirin therapy for coronary artery disease (CAD), CAD patients with metabolic syndrome (MS) still tend to have coronary thrombotic events. We aimed t... Background Despite the proven benefits of clopidogrel combined aspirin therapy for coronary artery disease (CAD), CAD patients with metabolic syndrome (MS) still tend to have coronary thrombotic events. We aimed to investigate the influence of metabolic risk factors on the efficacy of clopidogrel treatment in patients with CAD undergoing percutaneous coronary intervention (PCI). Methods Cohorts of 168 MS and 168 non-MS subjects with CAD identified by coronary angiography (CAG) were enrolled in our study. MS was defined by modified Adult Treatment Panel Ⅲ criteria. All subjects had taken 100 mg aspirin and 75 mg clopidogrel daily for more than 1 month, and administered loading doses of 600 mg clopidogrel and 300 mg aspirin before PCI. Blood samples were taken 24 h after the loading doses of clopidogrel and aspirin. Platelet aggregation was measured using light transmittance aggregometry (LTA) and thrombelastography (TEG). Clopidogrel resistance was defined as more than 50% adenosine diphosphate (ADP) induced platelet aggregation as measured by TEG. Re- sults Platelet aggregation inhibition rate by ADP was significantly lower in patients with MS as measured both by TEG (55% + 31% vs. 68% ± 32%; P 〈 0.001) and LTA (29% ± 23% vs. 42% ± 29%; P 〈 0.001). In the multivariate analysis, elderly [OR (95% CI): 1.483 (1.047±.248); P = 0.002], obesity [OR (95% CI): 3.608 (1.241-10.488); P = 0.018], high fasting plasma glucose level [OR (95% CI): 2.717 (1.176±.277); P = 0.019] and hyperuricemia [OR (95% CI): 2.583 (1.095-6.094); P = 0.030] were all statistically risk factors for clopido- grel resistance. CAD patients with diabetes and obesity were more likely to have clopidogrel resistance than the CAD patients without dia- betes and obesity [75% (61/81) vs. 43% (67/156); P 〈 0.001]. Conclusions CAD patients with MS appeared to have poorer antiplatelet response to clopidogrel compared to those without MS. Obesity, diabetes and hyperuricemia were all significantly associated with clopido- grel resistance. 展开更多
关键词 Clopidogrel resistance Coronary artery disease Metabolic syndrome
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Distribution and Abundance of Pelagic Tunicates in the North Yellow Sea 被引量:3
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作者 Pietro Franco CHEN Hongju LIU Guangxing 《Journal of Ocean University of China》 SCIE CAS 2014年第5期782-790,共9页
In this paper, the distribution patterns and abundance of pelagic tunicates in the North Yellow Sea of China during the period 2006-2007 were analyzed. Zooplankton samples were obtained with vertical towing from botto... In this paper, the distribution patterns and abundance of pelagic tunicates in the North Yellow Sea of China during the period 2006-2007 were analyzed. Zooplankton samples were obtained with vertical towing from bottom to surface using a WP2 plankton net(200 μm mesh size; mouth area: 0.25 m2). Five species belonging to two classes were identified: Oikopleura dioica, O. longicauda and Fritillaria borealis belonging to class Appendicularia; Salpa fusiformis and Doliolum denticulatum of class Thaliacea. O. dioica and O. longicauda were the dominant species, occurring in the samples of all four seasons, with different distribution patterns. Their maximum abundance were 1664.7 ind. m-3(spring) and 1031.7 ind. m-3(spring) respectively. Following Oikopleura spp. were D. denticulatum, which was found only in autumn with an average abundance of 149.6 ind. m-3, and S. fusiformis, which was detected all the year long except for autumn with low abundance(max. abundance 289.4 ind. m-3 in summer). Only a very small amount of F. borealis was detected in summer samples, with an average abundance of 2.7 ind. m-3. The relationship between tunicates abundances and the environmental factors was analyzed using the stepwise regression model for each species. The variation of appendicularian abundance showed a significant correlation with the surface water temperature and with the concentration of Chl-a. No relationship was found between tunicates abundance and salinity, likely due to the slight changes in surface salinity of the studied area during the four seasons. Salps abundance and that of doliolids were significantly correlated to bottom water temperature, indicating that these two species(S. fusiformis and D. denticulatum) migrate vertically in the water column. In particular D. denticulatum, known to be a warm water species, showed not only an important correlation with water temperature, but also a spatial distribution connected to the warm currents in the North Yellow Sea. The occurrence of D. denticulatum represents an interesting result never found in past research work. Water temperature, algal distribution and currents were the most relevant environmental factors influencing the tunicate abundance and distribution in the North Yellow Sea. Further research is needed in order to get more information on the ecology of these organisms and to better understand their role in the ecosystem including the oceanic food web. 展开更多
关键词 North Yellow Sea pelagic tunicates ABUNDANCE DISTRIBUTION sea surface temperature
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Ising Model on an Infinite Ladder Lattice
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作者 GAO Xing-Ru 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期553-562,共10页
In this paper we propose an Ising model on an infinite ladder lattice, which is made of two infinite Ising spin chains with interactions. It is essentially a quasi-one-dimessional Ising model because the length of the... In this paper we propose an Ising model on an infinite ladder lattice, which is made of two infinite Ising spin chains with interactions. It is essentially a quasi-one-dimessional Ising model because the length of the ladder lattice is infinite, while its width is finite. We investigate the phase transition and dynamic behavior of Ising model on this quasi-one-dimessional system. We use the generalized transfer matrix method to investigate the phase transition of the system. It is found that there is no nonzero temperature phase transition in this system. At the same time, we are interested in Glauber dynamics. Based on that, we obtain the time evolution of the local spin magnetization by exactly solving a set of master equations. 展开更多
关键词 Ising model general transfer matrix phase transition Glauber dynamics critical slow down
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Impacts of Drought and Human Activity on Vegetation Growth in the Grain for Green Program Region,China 被引量:6
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作者 WANG Hao LIU Guohua +3 位作者 LI Zongshan YE Xin FU Bojie LV Yihe 《Chinese Geographical Science》 SCIE CSCD 2018年第3期470-481,共12页
The Chinese government adopted six ecological restoration programs to improve its natural environments. Although these programs have proven successful in improving local environments, some studies have questioned thei... The Chinese government adopted six ecological restoration programs to improve its natural environments. Although these programs have proven successful in improving local environments, some studies have questioned their performance when regions suffer from drought. Whether we should consider the effects of drought on vegetation change in assessments of the benefits of ecological restoration programs is unclear. Therefore, taking the Grain for Green Program(GGP) region as a study area, we estimated vegetation growth in the region from 2000–2010 to clarify the trends in vegetation and their driving forces. Results showed that: 1) vegetation growth increased in the GGP region during 2000–2010, with 59.4% of the area showing an increase in the Normalized Difference Vegetation Index(NDVI). This confirmed the benefits of the ecological restoration program. 2) Drought can affect the vegetation change trend, but human activity plays a significant role in altering vegetation growth, and the slight downward trend in the NDVI was not consistent with the severity of the drought. Positive human activity led to increased NDVI in 89.13% of areas. Of these, 22.52% suffered drought, but positive human activity offset the damage in part. 3) Results of this research suggest that appropriate human activity can maximize the benefits of ecological restoration programs and minimize the effects of extreme weather. We therefore recommend incorporating eco-risk assessment and scientific management mechanisms in the design and management of ecosystem restoration programs. 展开更多
关键词 Grain for Green Program Normalized Difference Vegetation Index(NDVI) climate fluctuation human activity China
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