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控制理论与应用（英文版） 2013年第3期11卷 351-358页

作者： P.MUTHUKUMAR c.RAJIVgANTHI Department of Mathematics Gandhigram Rural Institute-Deemed University

Many practical systems in physical and technical sciences have impulsive dynamical behaviors during the evolution process which can be modeled by impulsive differential equations. In this paper, we prove the approximate controllability of control systems governed by a class of impulsive neutral stochastic functional differential system with state-dependent delay in Hilbert spaces. Sufficient conditions for approximate controllability of the control systems are established under the natural assumption that the corresponding linear system is approximately controllable. The results are obtained by using semigroup theory, stochastic analysis techniques, fixed point approach and abstract phase space axioms. An example is provided to illustrate the application of the obtained results.

关键词： Approximate controllability Hilbert space Impulsive neutral stochastic functional differential system Semigroup theory Sadovskii’s fixed point theorem

On Quasi-Reduced Quadratic Forms

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Acta Mathematica Sinica,English Series 2010年第8期26卷 1425-1448页

作者： E. DUBOIS c. LEVESQUE Eugene Dubois UMR 6138 CNRS Dep. de mathematiques et mecanique BP 5186 U. de Caen Basse-Normandie 14032 Caen France claude Levesque CICMA et Departement de mathematiques et de statistique U. Laval Quebec P. Qudbec Canada G1K 7P4

With the help of continued fractions, we plan to list all the elements of the set Q△ = {aX2 ＋ bXY ＋ cY2 ： a,b, c ∈Z, b2 - 4ac = △ with 0 ≤ b 〈 √△}of quasi-reduced quadratic forms of fundamental discriminant △. As a matter of fact, we show that for each reduced quadratic form f = aX2 ＋ bXY ＋ cY2 = （a, b, c） of discriminant △〉0（and of sign σ（f） equal to the sign of a）, the quadratic forms associated with f and defined by {〈a＋bu＋cu2,b＋2cu.c〉},with 1≤σ（f）u≤b/2｜c｜（whenever they exist）, 〈c,-b-2cu,a＋bu＋cu2〉 with b/2｜c｜≤σ（f）u≤[w（f）]=[b＋√△/2｜c｜], are all different from one another and build a set I（f） whose cardinality is #I（f）={1＋[ω（f）],when（2c）｜b,[ω（f）],when （2c）｜b. If f and g are two different reduced quadratic forms, we show that I（f） ∩ I（g） = Ф. Our main result is that the set Q△ is given by the disjoint union of all I（f） with f running through the set of reduced quadratic forms of discriminant △〉0. This allows us to deduce a formula for #（Q△） involving sums of partial quotients of certain continued fractions.

关键词： Quadratic forms reduced forms equivalence of forms class numbers quadratic fields,continued fractions

Hormones and phenotypic plasticity： Implications for the evolution of integrated adaptive phenotypes

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current Zoology 2013年第4期59卷 506-525页

作者： Sean c. LEMA Jun KITANO Biological Sciences Department Center for Coastal Marine Sciences California Polytechnic State University San Luis Obispo CA 93407-0401 Ecological genetics Laboratory National Institute of Genetics Mishima Shizuoka Japan

It is generally accepted that taxa exhibit genetic variation in phenotypic plasticity, but many questions remain unanswered about how divergent plastic responses evolve under dissimilar ecological conditions. Hormones are signaling molecules that act as proximate mediators of phenotype expression by regulating a variety of cellular, physiological, and behavioral responses. Hormones not only change cellular and physiological states but also influence gene expression directly or indirectly, thereby linking environmental conditions to phenotypic development. Studying how hormonal pathways respond to environmental variation and how those responses differ between individuals, populations, and species can expand our understanding of the evolution of phenotypic plasticity. Here, we explore the ways that the study of hormone signaling is providing new insights into the underlying proximate bases for individual, population or species variation in plasticity. Using several studies as exemplars, we examine how a ‘norm of reaction’ approach can be used in investigations of hormone-mediated plasticity to inform the following: 1) how environmental cues affect the component hormones, receptors and enzymes that comprise any endocrine signaling pathway, 2) how genetic and epigenetic variation in endocrine-associated genes can generate variation in plasticity among these diverse components, and 3) how phenotypes mediated by the same hormone can be coupled and decoupled via independent plastic responses of signaling components across target tissues. Future studies that apply approaches such as reaction norms and network modeling to questions concerning how hormones link environmental stimuli to ecologically-relevant phenotypic responses should help unravel how phenotypic plasticity evolves.

关键词：表型可塑性激素信号自适应环境因素进化集成遗传变异生理状态

Research,Extension,and good Farming Practices Improve Water Quality and Productivity

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Journal of Integrative Agriculture 2012年第1期11卷 14-30页

作者： clinton c Shock candace B Shock Oregon State University Malheur Experiment Station Scientific Ecological Services

Agriculture in southeastern Oregon and southwestern Idaho known collectively as the Treasure Valley has depended on furrow irrigation using heavy inputs of water and nitrogen （N） fertilizer. crop rotations include onion, corn, wheat, sugar beet, potato, bean, and other crops. By 1986 groundwater had become contaminated with nitrate and residues of the herbicide chlorthal-dimethyl （DcPA）; an official groundwater management area was established by the Oregon Department of Environmental Quality along with an action plan and well monitoring network. The action plan allowed for a trial period to see whether voluntary changes would improve trends. Researchers, producers, and agencies cooperated to develop production options that had the possibility of being both environmentally protective and cost effective. Options were tested to improve irrigation practices, increase N fertilizer use efficiency on several rotation crops, and find a cost effective replacement for DcPA. Research demonstrated the opportunity for increased productivity through both irrigation scheduling and the adoption of drip and sprinkler systems. Fertilizer research demonstrated that smaller, more frequent N applications were more efficient than a single large application. Effective, lower cost herbicides replaced DcPA. Research results were effectively delivered through many means and voluntarily adopted. Both groundwater nitrate and DcPA residues are declining. Productivity has increased.

关键词： DcPA drip irrigation groundwater nitrate irrigation management irrigation scheduling nutrient management voluntary cooperation

Spin squeezing in Dicke-class of states with non-orthogonal spinors

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chinese Physics B 2019年第6期28卷 66-71页

作者： K S Akhilesh K S Mallesh Sudha Praveen g Hegde Department of Physics University of MysoreManasagangotriMysuru-570006KarnatakaIndia Department of Physics Kuvempu UniversityShankaraghattaShimoga-577451India Inspire Institute Inc. AlexandriaVirginia 22303USA

The celebrated Majorana representation is exploited to investigate spin squeezing in different classes of pure symmetric states of N qubits with two distinct spinors, namely the Dicke-class of states. On obtaining a general expression for spin squeezing parameter, the variation of squeezing for different configurations is studied in detail. It is shown that the states in the Dicke-class, characterized by two-distinct non-orthogonal spinors, exhibit squeezing.

关键词： Majorana representation of pure symmetric multiqubit states spin squeezing Dicke states

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性传播疾病的性伴通知策略

生殖与避孕 2005年第6期25卷 363-370页

作者： Mathews c coetzee N Zwarenstein M Lombard c guttmacher S Oxman A Schmid g 刘善民单位不详

性伴通知是通知被诊断为STD患者(指示患者)的性伴，他们易于感染，有必要到卫生服务机构就诊。其临床目标之一是防止指示患者的再感染：另一个是公共卫生目标，减少STDs的传播。人部分感染STD的人既无感染症状，又无体征。如通过性伴通... 详细信息

性伴通知是通知被诊断为STD患者(指示患者)的性伴，他们易于感染，有必要到卫生服务机构就诊。其临床目标之一是防止指示患者的再感染：另一个是公共卫生目标，减少STDs的传播。人部分感染STD的人既无感染症状，又无体征。如通过性伴通知识别的淋病男性患者中，22％-68％是无症状的(Holmes1990)。要实现上述目标，性伴通知是能联系到这些个体的两个策略之一，

关键词：性传播疾病性伴通知策略流行病学医生通知约定通知

Estimating Evapotranspiration Using chloride Mass Balance in a New Mexico Paired Basin Study 2009-2019

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Journal of Water Resource and Protection 2023年第4期15卷 115-129页

作者： Amy c. Lewis Daniel cadol HydroAnalytics LLc Santa Fe NM USA New Mexico Institute of Mining and Technology Socorro NM USA

A paired basin study in the upper Santa Fe River watershed following forest thinning and prescribed burns successfully measured water budget components in a treated and an untreated (control) basin. The paired basin study was established to investigate questions that have arisen regarding changes in water yield from forest treatments. Precipitation, stream flow, soil moisture, and chloride concentrations in precipitation and stream flow were measured to quantify the water budget components. The results from eleven years of data collection and analysis have a high degree of confidence with respect to measuring the water budget components based on the mass balance of water and chloride. The differences in the geologic structure and topography between the two paired basins appeared to impact the water budgets more than the forest treatments, except during periods when winter precipitation and snowmelt represented a significant component of inflow. Although this paired basin study was not able to portray a simple relationship between forest thinning and water yield, the chloride concentration methodology used to estimate evapotranspiration (ET) was successful. These detailed observations of chloride deposition and transport characteristics may be relevant for other researchers working in forested basins with substantial ET. ET rates were estimated by examining the cycle of chloride entering and exiting each basin over six integration periods. ET was estimated to be about 90% to 94% of precipitation in the treated basin and 77% to 86% in the control basin. The higher ET in the treated basin both before and after forest treatments may be due to the much greater area of west-facing hillslopes in the treated basin, which receive warm afternoon sun, and the greater area of rock cover in the control basin. Variation in the chloride concentration of collected precipitation samples from different sites indicates that horizontal precipitation of chloride in the tree canopy is an

关键词： Evapotranspiration chloride Mass Balance Paired Basins Water Budgets Horizontal Precipitation

Magnetic resonance spectroscopy to study hepatic metabolism in diffuse liver diseases, diabetes and cancer

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World Journal of gastroenterology 2010年第13期16卷 1577-1586页

作者： Pieter c Dagnelie Susanne Leij-Halfwerk Department of Epidemiology Maastricht University

This review provides an overview of the current state of the art of magnetic resonance spectroscopy (MRS) in in vivo investigations of diffuse liver disease. So far, MRS of the human liver in vivo has mainly been used as a research tool rather than a clinical tool. The liver is particularly suitable for static and dynamic metabolic studies due to its high metabolic activity. Furthermore, its relatively superfi cial position allows excellent MRS localization, while its large volume allows detection of signals with relatively low intensity. This review describes the application of MRS to study the metabolic consequences of different conditions including diffuse and chronic liver diseases, congenital diseases, diabetes, and the presence of a distant malignancy on hepatic metabolism. In addition, future prospects of MRS are discussed. It is anticipated that future technical developments such as clinical MRS magnets with higher fi eld strength (3 T) and improved delineation of multicomponent signals such as phosphomonoester and phosphodiester using proton decoupling, especially if combined with price reductions for stable isotope tracers, will lead to intensifi ed research into metabolic syndrome, cardiovascular disease, hepato-biliary diseases, as well as non-metastatic liver metabolism in patients with a distant malignant tumor.

关键词： cancer cirrhosis Diabetes Diffuse liver disease Hepatitis Magnetic resonance spectroscopy

Are Polyploid Species Less Vulnerable to climate change? A Simulation Study in North American crataegus

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American Journal of climate change 2023年第3期12卷 359-375页

作者： Somayeh Naghiloo Jana c. Vamosi Department of Biological Sciences University of Calgary Calgary Canada

Understanding the mechanisms underlying plant responses to climate change is an important step toward developing effective mitigation strategies. Polyploidy is an important evolutionary trait that can influence the capacity of plants to adapt to climate change. The environmental flexibility of polyploids suggests their resiliency to climate change, however, such hypotheses have not yet received empirical evidence. To understand how ploidy level may influence response to climate change, we modeled the current and future distribution of 54 crataegus species under moderate to severe environments and compared the range change between diploids and polyploids. The majority of studied species are predicted to experience considerable range expansion. We found a negative interaction between ploidy and ecoregions in determining the response to climate change. In extreme environments, polyploids are projected to experience a higher range expansion than diploids with climate change, while the opposite is true for moderate environments. The range expansion of crataegus species can be attributed to their tolerance for a wide range of environmental conditions. Despite the higher tolerance of polyploids to extreme environments, they do not necessarily outperform diploids in moderate environments, which can be attributed to the varying nature of species interactions along a stress gradient.

关键词： climate change crataegus Ecoregion North America Range change Species Distribution Modeling

Effects of Numerical Methods on the calculation of Developing Plane channel Flow

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Journal of Applied Mathematics and Physics 2022年第6期10卷 2086-2104页

作者： Ronald M. c. So Mechanical Engineering Department The Hong Kong Polytechnic University Hong Kong China

In wall-bounded turbulent flow calculations, the past focus has been directed to the modelling of the Reynolds-stress gradients. Not much attention has been paid to the effects of the numerical methods used to calculate these terms and the modelled equations. Discrepancies between model calculations and measurements are quite often attributed to incorrect modelling, while the suitability and accuracy of the numerical methods used are seldom scrutinized. Instead, alternate near-wall and Reynolds-stress models are proposed to remedy the incorrect turbulent flow calculations. On the other hand, if care is not taken in the numerical treatment of the Reynolds-stress gradient terms, physically unrealistic results and solution instability could occur. Previous studies by the author and his collaborators on the effects of numerical methods have shown that some of the more commonly used numerical methods could enhance numerical stability in the solution procedure but would introduce considerable inaccuracy to the results. The flow cases chosen to demonstrate these inaccuracies are a backstep flow and flow in a square duct, where flow complexities are present. The current investigation attempts to show that the above-mentioned effects of numerical methods could also occur in the calculation of a developing plane channel flow, where flow complexities are absent. In addition, this study shows that the results thus obtained lead to a predicted skin friction coefficient that is influenced more by the numerical method used than by the turbulence model invoked. Together, these results show that numerical treatment of the Reynolds-stress gradients in the equations play an important role, even for a developing plane channel flow.

关键词： Numerical Representation of Pressure-gradient Terms Numerical Representation of Stress-gradient Terms Numerical grid Effects Numerical Methods Effects calculation of Plane channel Flow