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Ochratoxin A induces abnormal tryptophan metabolism in the intestine and liver to activate AMPK signaling pathway
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作者 Weiqing Ma Yang Fu +8 位作者 Shanshan Zhu Daiyang Xia Shuangshuang Zhai Deqin Xiao Yongwen Zhu Michel Dione Lukuyu Ben Lin Yang Wence Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2674-2685,共12页
Background Ochratoxin A(OTA)is a mycotoxin widely present in raw food and feed materials and is mainly pro-duced by Aspergillus ochraceus and Penicillium verrucosum.Our previous study showed that OTA principally induc... Background Ochratoxin A(OTA)is a mycotoxin widely present in raw food and feed materials and is mainly pro-duced by Aspergillus ochraceus and Penicillium verrucosum.Our previous study showed that OTA principally induces liver inflammation by causing intestinal flora disorder,especially Bacteroides plebeius(B.plebeius)overgrowth.However,whether OTA or B.plebeius alteration leads to abnormal tryptophan-related metabolism in the intestine and liver is largely unknown.This study aimed to elucidate the metabolic changes in the intestine and liver induced by OTA and the tryptophan-related metabolic pathway in the liver.Materials and methods A total of 30 healthy 1-day-old male Cherry Valley ducks were randomly divided into 2 groups.The control group was given 0.1 mol/L NaHCO3 solution,and the OTA group was given 235μg/kg body weight OTA for 14 consecutive days.Tryptophan metabolites were determined by intestinal chyme metabolomics and liver tryptophan-targeted metabolomics.AMPK-related signaling pathway factors were analyzed by Western blot-ting and mRNA expression.Results Metabolomic analysis of the intestinal chyme showed that OTA treatment resulted in a decrease in intesti-nal nicotinuric acid levels,the downstream product of tryptophan metabolism,which were significantly negatively correlated with B.plebeius abundance.In contrast,OTA induced a significant increase in indole-3-acetamide levels,which were positively correlated with B.plebeius abundance.Simultaneously,OTA decreased the levels of ATP,NAD+and dipeptidase in the liver.Liver tryptophan metabolomics analysis showed that OTA inhibited the kynurenine metabolic pathway and reduced the levels of kynurenine,anthranilic acid and nicotinic acid.Moreover,OTA increased the phosphorylation of AMPK protein and decreased the phosphorylation of mTOR protein.Conclusion OTA decreased the level of nicotinuric acid in the intestinal tract,which was negatively correlated with B.plebeius abundance.The abnormal metabolism of tryptophan led to a deficiency of NAD+and ATP in the liver,which in turn activated the AMPK signaling pathway.Our results provide new insights into the toxic mechanism of OTA,and tryptophan metabolism might be a target for prevention and treatment. 展开更多
关键词 AMPK Metabolomics Ochratoxin A Tryptophan metabolism
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A Set of Lie Symmetrical Conservation Law for Rotational Relativistic Hamiltonian Systems 被引量:6
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作者 LUOShao-Kai JIALi-Qun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第3X期265-268,共4页
For the rotational relativistic Hamiltonian system, a new type of the Lie symmetries and conserved quantities are given. On the basis of the theory of invariance of differential equations under infinitesimal transfor... For the rotational relativistic Hamiltonian system, a new type of the Lie symmetries and conserved quantities are given. On the basis of the theory of invariance of differential equations under infinitesimal transformations, and introducing infinitesimal transformations for generalized coordinates qs and generalized momentums ps, the determining equations of Lie symmetrical transformations of the system are constructed, which only depend on the canonical variables.A set of non-Noether conserved quantities are directly obtained from the Lie symmetries of the system. An example is given to illustrate the application of the results. 展开更多
关键词 哈密顿系统 李对称 非NOETHER守恒量 守恒规律 转动相对论 力学系统
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Spirostane Steroidal Saponins from the Undergroud Parts of Tupistra chinensis 被引量:4
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作者 GuangXuWU XiaoYiWEI WeiXinCHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第7期911-914,共4页
Two new spirostanol saponins, (25S)-spirostane-1β,3β,5β-triol 3-O-β-D-glucopyrano- side 1 and rhodeasapogenin 3-O-β-D-glucopyranosyl-(1 → 4)-β-D-glucopyranoside 2, together with a known saponin, rhodeasapogenin... Two new spirostanol saponins, (25S)-spirostane-1β,3β,5β-triol 3-O-β-D-glucopyrano- side 1 and rhodeasapogenin 3-O-β-D-glucopyranosyl-(1 → 4)-β-D-glucopyranoside 2, together with a known saponin, rhodeasapogenin 3-O-β-D-glucopyranoside 3, were isolated from the underground parts of Tupistra chinensis Bak.. Their structures were determined by spectroscopic analysis. 展开更多
关键词 Tupistra chinensis Bak. LILIACEAE steroidal saponins (25S)-spirostane-1β 5β-triol 3- O-β-D-glucopyranoside rhodeasapogenin 3-O-β-D-glucopyranosyl-(1 4)-β-D-glucopyranoside.
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Noether Symmetry Can Lead to Non-Noether Conserved Quantity of Holonomic Nonconservative Systems in General Lie Transformations 被引量:4
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作者 LUOShao-Kai JIALi-Qun CAIJian-Le 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期193-196,共4页
For the holonomic nonconservative system, by using the Noether symmetry, a non-Noether conserved quantity is obtained directly under general infinitesimal transformations of groups in which time is variable. At first,... For the holonomic nonconservative system, by using the Noether symmetry, a non-Noether conserved quantity is obtained directly under general infinitesimal transformations of groups in which time is variable. At first,the Noether symmetry, Lie symmetry, and Noether conserved quantity are given. Secondly, the condition under which the Noether symmetry is a Lie symmetry under general infinitesimal transformations is obtained. Finally, a set of nonNoether conserved quantities of the system are given by the Noether symmetry, and an example is given to illustrate the application of the results. 展开更多
关键词 holonomic conservative system noether symmetry non-Noether conservedquantity general inifinitesimal transformations of groups
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A set of Lie symmetrical non-Noether conserved quantity for the relativistic Hamiltonian systems 被引量:4
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作者 罗绍凯 贾利群 蔡建乐 《Chinese Physics B》 SCIE EI CAS CSCD 2003年第8期841-845,共5页
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Research of PDC Bit Compact Die With FEM and Optimum Method
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作者 ZhouSizhu LiChenggang +1 位作者 CaoJiguang HuaJian 《Petroleum Science》 SCIE CAS CSCD 2004年第1期59-64,82,共7页
In mould design, it is necessary for a designer to ensure that the cylinder has enough intensity in both the prestressed and synthesis states. An individual layer cylindrical mould cannot withstand a very high pressur... In mould design, it is necessary for a designer to ensure that the cylinder has enough intensity in both the prestressed and synthesis states. An individual layer cylindrical mould cannot withstand a very high pressure needed in polycrystalline diamond composite (PDC) production. So, multi-layer prepressure combination assemble moulds are often used. The analysis conducted here is to study the interaction of cylindrical layers and to explain how to obtain enough load capability with the lowest requirement of material performance. The ratio of the pressure cylinder radius of synthetic diamond is 3.27, which is close to the optimal value and can be used as structure size in a design for PDC bit compact die. There is a linear relationship between the internal and external pressures under a special tangent stress on the inner wall of the pressure cylinder. So, when two of the three parameters (the internal pressure, external pressure, and the requirement value of the tangent stress on the inner wall of the pressure cylinder) are given, the third can be obtained. The sleeve acts as a bridge?between the pressure cylinder and the steel belts. The optimum model developed in this paper can be used in PDC bit compact die design and other similar prestressed cold extrusion die design. 展开更多
关键词 PDC bit COMPACT DIE optimum design finite element method
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Time evolution of the intensity correlation function in a single-mode laser driven by both the coloured pump noise with signal modulation and the quantum noise with cross-correlation between the real and imaginary parts 被引量:1
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作者 程庆华 曹力 +1 位作者 徐大海 吴大进 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第6期1159-1167,共9页
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An Electromagnetic Model for Jet Power from an Advection Dominated Accretion Flow around a Rotating Black Hole 被引量:1
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作者 龚小龙 汪定雄 《Chinese Physics Letters》 SCIE CAS CSCD 2005年第5期1293-1295,共3页
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Carbon isotopic composition and genetic types of natural gas in the Sichuan Basin, China
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作者 Jin-ning peng Dong-yan Wang +2 位作者 Guang-xiang Liu Min Zhang Feng-li Li 《Acta Geochimica》 EI CAS CSCD 2017年第1期102-111,共10页
The origin and genetic types of natural gas in the Sichuan Basin are still disputed.To classify the origin and genetic types in different areas,the paper analyzes the carbon isotopic composition of gases and geologic ... The origin and genetic types of natural gas in the Sichuan Basin are still disputed.To classify the origin and genetic types in different areas,the paper analyzes the carbon isotopic composition of gases and geologic features in the Sichuan Basin.The results showed that the gas sourced from terrestrial layers is typically characterized by terrestrial origin and was mainly accumulated nearby to form reservoir.The carbon isotopic composition of gas showed a normal combination sequence distribution,suggesting that natural gas in continental strata is not affected by secondary alteration or that this deformation is very weak.The gas source is singular,and only gas from the southern and northern Sichuan Basin shows the characteristic of mixed sources.However,marine gas presents the characteristics of an oil-formed gas.The carbon isotopic composition of natural gas in the western and central part of the basin mostly distributes in a normal combination sequence,and few of them showed an inversion,indicating that the gas perhaps had not experienced secondary alteration.The carbon isotopic composition of marine-origin gas in the southern,northern and eastern Sichuan Basin displays a completely different distribution pattern,which is probably caused by different mixing ratio of gas with multi-source and multi-period. 展开更多
关键词 The Sichuan Basin ALKANE Carbon isotope Genetic type
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A Potential-Reduction Algorithm for Linear Complementarity Problems
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作者 WangYan-jin FeiPu-sheng YanZi-zong 《Wuhan University Journal of Natural Sciences》 CAS 2004年第2期144-148,共5页
Feasible-interior-point algorithms start from a strictly feasible interior point, but infeassible-interior-point algorithms just need to start from an arbitrary positive point, we give a potential reduction algorithm ... Feasible-interior-point algorithms start from a strictly feasible interior point, but infeassible-interior-point algorithms just need to start from an arbitrary positive point, we give a potential reduction algorithm from an infeasible-starting-point for a class of non-monotone linear complementarity problem. Its polynomial complexity is analyzed. After finite iterations the algorithm produces an approximate solution of the problem or shows that there is no feasible optimal solution in a large region. Key words linear complementarity problems - infeasible-starting-point - P-matrix - potential function CLC number O 221 Foundation item: Supported by the National Natural Science Foundation of China (70371032) and the Doctoral Educational Foundation of China of the Ministry of Education (20020486035)Biography: Wang Yan-jin (1976-), male, Ph. D candidate, research direction: optimal theory and method. 展开更多
关键词 linear complementarity problems infeasible-starting-point P-MATRIX potential function
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Intensity Correlation Function of a Single-Mode Laser Driven by Colored Cross-Correlation Noises in Modulation of a Bias Signal
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作者 HANLi-Bo CAOLi +1 位作者 YANGHong-Quan WUDa-Jin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4期666-670,共5页
By using the linear approximation method, the intensity correlation function is calculated for a single-mode laser modulated by a bias signal and driven by colored pump and quantum noises with colored cross-correlatio... By using the linear approximation method, the intensity correlation function is calculated for a single-mode laser modulated by a bias signal and driven by colored pump and quantum noises with colored cross-correlation. We found that, when the correlation time between the two noises is very short, the behavior of the intensity correlation function versus the time, in addition to decreasing monotonously, also exhibits several cases, such as one maximum, one minimum, and two extrema. When the correlation time between the two noises is very long, the behavior of the intensity correlation function exhibits oscillation and the envelope is similar to the case of short cross-correlation time. 展开更多
关键词 linear approximation method intensity correlation function bias signal modulation oscillation
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A new non-Noether conserved quantity of the relativistic holonomic nonconservative systems in general Lie transformations 被引量:1
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作者 罗绍凯 蔡建乐 贾利群 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第4期656-659,共4页
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Origin of Natural Gas in Kekeya Field, Tarim Basin, China
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作者 HouDujie XiaoZhongyao +2 位作者 TangYoujun ZhuJunzhang LiXianqing 《Journal of China University of Geosciences》 SCIE CSCD 2004年第1期91-98,共8页
This paper is mainly concentrated on the geochemical characteristics and origin of gas of Kekeya field in the Tarim basin, NW China. This study shows that Permian mudstone is the main source rock of oil and gas. Based... This paper is mainly concentrated on the geochemical characteristics and origin of gas of Kekeya field in the Tarim basin, NW China. This study shows that Permian mudstone is the main source rock of oil and gas. Based on the carbon isotopes of C 1-C 4, the carbon isotope of gas in Kekeya field is a little heavier than that in the typical marine-derived gas. The relationship between carbon isotopes of methane and ethane is coincident with Faber equation of gas derived from organic matter Ⅰ/Ⅱ. The majority of gas maturity is estimated, based on the formula, at 1.8 %-2.2 % besides K2 and K18 wells. In addition, the gas derived from 0.9 %-1.2 % R o source rocks may also be mixture. 40Ar/ 36Ar and 3He/ 4He ratios from the gas samples also support the mixing process. Moreover, the gas in this region is mainly generated from more mature source rocks although the low mature gas exists. 展开更多
关键词 natural gas ORIGIN KEKEYA source rock.
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Problems and Countermeasures of Taihu Port Farm in Jingzhou City after Function Reform of Running the Society
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作者 Hefan XU Jun ZHENG Jiafeng YU 《Asian Agricultural Research》 2019年第8期1-4,共4页
Deepening function reform of running the society of state-owned farm is an important strategic plan made by the Party Central Committee and the State Council,and is also ' hard bone' bitten by fully implementi... Deepening function reform of running the society of state-owned farm is an important strategic plan made by the Party Central Committee and the State Council,and is also ' hard bone' bitten by fully implementing the strategy of rural revitalization and promoting the modernization of agriculture and countryside. In this paper,the problems of Taihu Port Farm in Jingzhou City after function reform of running the society are systematically and comprehensively analyzed via field research,and corresponding countermeasures are proposed. The research could provide beneficial reference and experience reference for deepening function reform of running the society of current state-owned farm. 展开更多
关键词 Function reform of running the SOCIETY of STATE-OWNED FARM Agricultural MODERNIZATION Rural REVITALIZATION Taihu PORT FARM
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Study of Commercial Wheat Flour Milling Process:Relation of Flour Yield,Ash and Protein Contents of Flour Mill and Characteristics of Wheat Blend
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作者 Y S Kim C W Deyoe +1 位作者 O K Chung E Haque 《食品科学》 EI CAS CSCD 北大核心 2006年第11期146-152,共7页
The profit margin in the flour milling industry is quite narrow,so high-quality raw materials and efficiency of milling operations are crucial for every company. Many flour mills,especially those which import wheat fr... The profit margin in the flour milling industry is quite narrow,so high-quality raw materials and efficiency of milling operations are crucial for every company. Many flour mills,especially those which import wheat from other countries and have limited storage space for the different varieties or classes of wheat,can not afford to buy low quality wheat. Consequently,a mathematical model which can test the impact and interactions of raw materials,in technical point of view,would be a useful decision-making tool for the milling industry. A flour miller tests wheat for physical and chemical characteristics,cleanness and soundness. The miller also performs experimental milling,if available,to have some idea how the given wheat will behave during commercial milling. Based on these test results,the miller can only guess the commercial milling results such as flour yields and flour ash and protein contents. Thus,the objective of this study was to develop empirical equations to estimate commercial milling results,using the physical,chemical and experimental milling data of the given wheat blend and also,additionally,flour ash and protein specifications of the end-user. This was done by using the actual commercial milling procedures and their wheat physical,chemical,experimental milling data,and other vital data. Data were collected from a commercial mill located in East Asia that had four production lines and used wheat blend combinations from five different wheat classes,i.e. Hard Red Winter (HRW),Dark Northern Spring (DNS),Soft White (SW),Australian Soft (AS),and Australian Standard White (ASW) wheat to produce over 40 different products. The wheat physical and chemical characteristics included test weight,thousand kernel weight,ash and protein contents. The experimental milling data were straight-grade and patent flour yields,along with patent flour ash and protein contents from a Buhler experimental mill. The commercial milling results included the flour yields of patent,first clear,and second clear flours,as well as the ash and protein contents of commercial patent flours. Using multiple linear regression procedures,we have developed empirical equations to be able to estimate the commercial patent flour yields with R2 values above 0.90 for all four production lines,and commercial first clear flour yields with R2 values ranging 0.76 to 0.98,and the commercial patent flour protein contents with R2 values of 0.89 to 0.92. However,the yields of commercial second clear flours and the commercial patent flour ash contents were not able to be estimated with high coefficients of determination (R2 values). We recommend that the empirical equations for estimating commercial milling parameters should be derived using data from each individual flour milling company,for each production line of a given mill,and furthermore,tailored to specific products at a given ash and/or protein contents desired by end-users. 展开更多
关键词 Study of Commercial Wheat Flour Milling Process SFA BPP
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Jet Magnetically Accelerated from Advection Dominated Accretion Flow
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作者 龚小龙 姜志雄 《Chinese Physics Letters》 SCIE CAS CSCD 2014年第8期178-180,共3页
A jet model for the jet power arising from a steady, optically thin, advection dominated accretion flow (ADAF) around a Kerr black hole (BH) is proposed. We investigate the typical numerical solutions of ADAF, and... A jet model for the jet power arising from a steady, optically thin, advection dominated accretion flow (ADAF) around a Kerr black hole (BH) is proposed. We investigate the typical numerical solutions of ADAF, and calculate the jet power from an ADAF using a general relativistic version of electronic circuit theory. It is shown that the jet power concentrates in the inner region of the accretion flow, and the higher the degree to which the flow advection-dominated is, the lower the jet power from the ADAF is. 展开更多
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The Research of Complex System Property between Thermosensitive Polymer and Surfactant
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作者 Chao Ma Gang Wan Tang Tang 《Journal of Energy and Power Engineering》 2015年第8期721-726,共6页
In this paper, the rigid structural thermosensitive polymer (made in lab) of NBS (N-butyl styrene), N, N-DEAM (diethyl acrylamide) and AM (acrylamide) was prepared. The influence of viscosity for copolymer sol... In this paper, the rigid structural thermosensitive polymer (made in lab) of NBS (N-butyl styrene), N, N-DEAM (diethyl acrylamide) and AM (acrylamide) was prepared. The influence of viscosity for copolymer solution under different reaction conditions such as temperatures and inorganic salt (monovalent salt and divalent salt) was analyzed. The experiment studies the combination of polymer situation and three different types of surfactants under certain conditions of the room temperature (25℃) and the formation temperature (76℃). At last, the influence of the surfactant kinds and concentration on the viscosity of the polymer solution are studied. The results show that: The copolymer solution, the apparent viscosity of which decreases with the increasement of temperature, but its viscosity has suddenly increased and thereafter dropped in the transition temperature. So the temperature sensitive effect ofcopolymer is very significantly. When the concentration of inorganic salt and surfactant can be controlled in certain extent, the copolymer solution, the effect increases with the increasement of the concentration, but the viscosity of which decreases with the increasement of shear rate. Shear rate can be controlled in certain extent, shearing stability properties of the copolymer solution are proved. 展开更多
关键词 Butyl styrene hydrophobic monomer solution properties thermosensitive polymer surfactant.
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A Monte Carlo Study on Cone-Angle Property of the Quark- and Gluon-Jets Identified by b-Tag Method
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作者 陈刚 刘连寿 《Chinese Physics Letters》 SCIE CAS CSCD 2005年第4期839-842,共4页
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Phosphate Availability Alters Lateral Root Anatomy and Root Architecture of Fraxinus mandshurica Rupr. Seedlings 被引量:7
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作者 ChuWU XingWEI +1 位作者 Hai-LongSUN Zheng-QuanWANG 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2005年第3期292-301,共10页
Abstract: Plants have evolved some mechanisms to maximize the efficiency of phosphorus acquisition. Changes in root architecture are one such mechanism. When Fraxinus mandshurica Rupr. seedlings were grown under condi... Abstract: Plants have evolved some mechanisms to maximize the efficiency of phosphorus acquisition. Changes in root architecture are one such mechanism. When Fraxinus mandshurica Rupr. seedlings were grown under conditions of low phosphorus availability, the length of cells in the meristem zone of the lateral roots was longer, but the length of cells in the elongation and mature zones of the lateral roots was shorter, compared with seedlings grown under conditions of high phosphorus availability. The elongation rates of primary roots increased as phosphorus availability increased, but the elongation rates of the branched zones of the primary roots decreased. The number of lateral root primordia and the length of the lateral roots decreased as phosphorus availability increased. The topological index (altitude slope) decreased as phosphorus availability increased, suggesting that root architecture tended to be herringbone-like when seedlings were grown under conditions of low phosphate availability. Herringbone-like root systems exploit nutrients more efficiently, but they have higher construction costs than root systems with a branching pattern. 展开更多
关键词 Fraxinus mandshurica Rupr lateral root anatomy phosphate availability root architecture
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Packing-type Measures of the Sample Paths of Fractional Brownian Motion
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作者 Zhen-longChen San-yangLiu Ci-wenXu 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2005年第2期335-352,共18页
Let Λ = {λ_k} be an infinite increasing sequence of positive integers withλ_k → ∞. Let X = {X(t), t ∈ R^N} be a multi-parameter fractional Brownian motion of index (0 【α 【 1) in R^d . Subject to certain hypot... Let Λ = {λ_k} be an infinite increasing sequence of positive integers withλ_k → ∞. Let X = {X(t), t ∈ R^N} be a multi-parameter fractional Brownian motion of index (0 【α 【 1) in R^d . Subject to certain hypotheses, we prove that if N 【 αd, then there exist positivefinite constants K_1 and K_2 such that, with unit probability, K_1 ≤ φ - p_Λ(X([0,1])~N) ≤ φ -p_Λ(G_rX([0,1])~N)) ≤ K_2 if and only if there exists γ 】 0 such that ∑ from k=1 to ∞ of1/λ_k~γ = ∞, where φ(s) = s^(N/α)(loglog 1/s)^(N/2(α)), φ - p_Λ(E) is the Packing-typemeasure of E,X([0, 1]) N is the image and G_rX([0, 1]~N ) = {(t,X(t)); t ∈ [0,1]~N} is the graph ofX, respectively. We also establish liminf type laws of the iterated logarithm for the sojournmeasure of X. 展开更多
关键词 Fractional Brownian motion packing-type measure image graph law ofiterated logarithm sojourn measure
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