Relevant bibliographies by topics / Time correlation functions

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Time correlation functions'

Author: Grafiati
Published: 19 February 2023

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Journal articles on the topic "Time correlation functions"

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Shimoji, Mitsuo, and Toshio Itami. "1.3 Time Correlation Functions and Memory Functions." Defect and Diffusion Forum 43 (January 1986): 22–34. http://dx.doi.org/10.4028/www.scientific.net/ddf.43.22.

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Hinze, G., G. Diezemann, and H. Sillescu. "Four-time rotational correlation functions." Europhysics Letters (EPL) 44, no. 5 (December 1, 1998): 565–70. http://dx.doi.org/10.1209/epl/i1998-00510-7.

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Franosch, Thomas. "Long-time limit of correlation functions." Journal of Physics A: Mathematical and Theoretical 47, no. 32 (July 29, 2014): 325004. http://dx.doi.org/10.1088/1751-8113/47/32/325004.

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Coretti, Alessandro, Sara Bonella, Lamberto Rondoni, and Giovanni Ciccotti. "Time reversal and symmetries of time correlation functions." Molecular Physics 116, no. 21-22 (May 17, 2018): 3097–103. http://dx.doi.org/10.1080/00268976.2018.1464674.

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Bikondoa, Oier. "On the use of two-time correlation functions for X-ray photon correlation spectroscopy data analysis." Journal of Applied Crystallography 50, no. 2 (February 17, 2017): 357–68. http://dx.doi.org/10.1107/s1600576717000577.

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Multi-time correlation functions are especially well suited to study non-equilibrium processes. In particular, two-time correlation functions are widely used in X-ray photon correlation experiments on systems out of equilibrium. One-time correlations are often extracted from two-time correlation functions at different sample ages. However, this way of analysing two-time correlation functions is not unique. Here, two methods to analyse two-time correlation functions are scrutinized, and three illustrative examples are used to discuss the implications for the evaluation of the correlation times and functional shape of the correlations.
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van Stokkum, I. H. M., P. I. M. Johannesma, and J. J. Eggermont. "Representation of time-dependent correlation and recurrence time functions." Biological Cybernetics 55, no. 1 (October 1986): 17–24. http://dx.doi.org/10.1007/bf00363974.

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Ignatyuk. "SHORT-WAVELENGTH ASYMPTOTICS OF TIME CORRELATION FUNCTIONS." Condensed Matter Physics 4, no. 2 (2001): 243. http://dx.doi.org/10.5488/cmp.4.2.243.

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Mócsy, Á., and P. Petreczky. "Describing charmonium correlation functions in Euclidean time." European Physical Journal Special Topics 155, no. 1 (March 2008): 101–6. http://dx.doi.org/10.1140/epjst/e2008-00593-2.

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Hood, Lindsay M., Denis J. Evans, and Gary P. Morriss. "Time correlation functions in the stress ensemble." Molecular Physics 62, no. 2 (October 10, 1987): 419–28. http://dx.doi.org/10.1080/00268978700102291.

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Egorov, S. A., and J. L. Skinner. "Semiclassical approximations to quantum time correlation functions." Chemical Physics Letters 293, no. 5-6 (September 1998): 469–76. http://dx.doi.org/10.1016/s0009-2614(98)00807-0.

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Dissertations / Theses on the topic "Time correlation functions"

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Alavi, Saman. "Density corrections to transport coefficients from time correlation functions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0019/NQ46308.pdf.

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Jou, Wen Chi. "The theoretical studies of time-correlation functions with the first principle molecular dynamics simulations on surfaces /." Tamsui : Tamkang University, Department of Chemistry, 2007. http://etds.lib.tku.edu.tw/etdservice/view_metadata?etdun=U0002-0207200714531200.

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Freire, Márcio de Melo. "Funções de Green em Mecânica Estatística." reponame:Repositório Institucional da UFC, 2014. http://www.repositorio.ufc.br/handle/riufc/9059.

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FREIRE, Márcio de Melo. Funções de Green em Mecânica Estatística. 2014. 56 f. Dissertação (Mestrado em Física) - Programa de Pós-Graduação em Física, Departamento de Física, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2014.
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Neste trabalho estabeleceremos as definições das funções de Green em mecânica estatística e suas propriedades básicas. Estas funções dependem duplamente do tempo e da temperatura. Isto pode ser observado por meio de suas definições, onde aparecem os valores médios dos produtos de operadores. Neste caso a média é feita sobre o ensemble grão-canônico. Os operadores envolvidos nestas funções satisfazem a equação de movimento de Heisenberg, o que nos permite descrever as equações de evolução para as funções de Green. Por meio da representação espectral das funções de correlação temporal, que é feita através da introdução de uma transformada de Fourier para mudar o sistema do espaço dos tempos para o espaço das frequências, podemos obter as representações espectrais para as funções de Green retardada, avançada e causal. Por último, faremos o uso da função de Green retardada para descrever a condutividade elétrica de um sistema de elétrons submetido a um campo elétrico externo dependente de tempo, em outras palavras, descreveremos o tensor de condutividade elétrica em termos da função de Green retardada e, por último, calcularemos a condutividade elétrica de um sistema de elétrons e fônons.
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Brookes, Sarah. "Fluids in Nanopores." Thesis, Griffith University, 2016. http://hdl.handle.net/10072/365467.

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Molecular modelling plays an important and complementary role to experimental studies. In this thesis we use molecular dynamic simulations and time correlation functions to examine the isomerization of n-butane and to perform a proof-of-concept demonstration, applying the dissipation theorem to calculating transport properties. Equilibrium molecular dynamics are used to determine the solvent shift and rate constants in the isomerization process of n-butane. Furthermore the effects of confining n-butane to a nanopore are examined and compared to in two different wall-models. The structure and dynamics of a fluid can be affected when confined to pores of nanometre widths. An understanding of the effects of confinement on the equilibrium composition of reacting mixtures, diffusion and adsorption rates, can lead to improvements in industrial processes such as in the food and pharmaceutical industry. A known effect of confinement is wetting of the walls due to interactions between the wall and the fluid. Examination of the local molecular fluid density across the pore has shown that the degree of wetting is a function of pore width, mean fluid density and wall surface density.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Natural Sciences
Science, Environment, Engineering and Technology
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DeVane, Russell H. "Molecular dynamics and time correlation function theories." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001309.

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De, Silva Weeraddana Manjula Kumara. "Correlation Imaging for Real-time Cardiac MRI." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1471346206.

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Kasprzyk, Christina Ridley. "Practical applications of molecular dynamics techniques and time correlation function theories." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001644.

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Ryderfors, Linus. "Two-Photon Excited Fluorescence Depolarisation : Experimental and Theoretical Development." Doctoral thesis, Uppsala University, Department of Photochemistry and Molecular Science, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9285.

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We have studied fundamental aspects of time-resolved two-photon excited fluorescence depolarisation. The thesis presents experimental as well as theoretical progress. We show that a multi-photon induced instrumental response function obtained from a suspension of gold nanoparticles is appropriate for the analysis of two-photon excited fluorescence decays obtained using time-correlated single photon counting detection. Theoretical expressions have been derived for the fluorescence anisotropy decay obtained upon two-photon excitation of various molecular systems in liquid solutions: a) an anisotropic rigid rotor that undergoes rotational diffusion in the presence of ultrafast unresolved restricted reorientations, e.g. librations. b) a molecular group covalently attached to a stationary macromolecule, and undergoing local reorientation in a uniaxial ordering potential. A new approach to the analysis of two-photon excited fluorescence depolarisation experiments was developed, which combines data obtained by using linearly and circularly polarised excitation light, in a global manner. In the analysis, knowledge about unresolved reorientations was obtained from one-photon excitation studies of the corresponding systems. By means of this procedure it has been possible to obtain quantitative information about the molecular two-photon absorption tensor for perylene and two of its derivatives. Thereby the symmetry of the final excited and intermediate vibronic states could be assigned. The analysis reveals that the two-photon transition studied with the 800 nm laser exhibits mixed character. An important finding from the experiments was that the two-photon absorption tensor appears to be solvent dependent. Furthermore, the thesis presents the first theoretical treatment of two-photon excited donor-donor energy migration in the presence of molecular reorientation and which applies the extended Förster theory. Explicit expressions for molecules that belong to the point groups D2h, D2 and C2v are given. Preliminary experiments are finally also reported on a two-photon excited donor-donor energy migration system consisting of a bisanthryl-bisteroid.

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Martins, Marcio Marques. "Influência de parâmetros moleculares em funções de correlação temporal na dinâmica de solvatação mecânica." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2004. http://hdl.handle.net/10183/6896.

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No presente trabalho descrevemos nossos resultados relativos à investigação da dinâmica de solvatação mecânica por meio de simulações por dinâmica molecular, respeitando o regime da resposta linear, em sistemas-modelo de argônio líquido com um soluto monoatômico ou diatômico dissolvido. Estudamos sistematicamente a influência dos parâmetros moleculares dos solutos (tamanho, polarizabilidade) e da densidade frente a vários modelos de solvatação. Funções de Correlação Temporal da Energia de Solvatação foram calculadas com relação à correlações de n-corpos (n = 2; 3) distinguindo interações repulsivas e atrativas para ambos os sistemas líquidos. Também obtivemos segundas derivadas temporais dessas funções referindo-se à parcelas translacionais, rotacionais e roto-translacionais na solução do diatômico. Encontramos que funções de correlação temporal coletivas podem ser razoavelmente bem aproximadas por correlações binárias a densidades baixas e, a densidades altas, correlações ternárias tornam-se mais importantes produzindo um descorrelacionamento mais rápido das funções coletivas devido a efeitos de cancelamento parciais. As funções de correlação para interações repulsivas e atrativas exibem comportamentos dinâmicos independentes do modelo de solvatação devido a fatores de escalonamento linear que afetam apenas as amplitudes das dessas funções de correlação temporal. Em geral, os sistemas com grau de liberdade rotacional apresentam tempos de correlação mais curtos para a dinâmica coletiva e tempos de correlação mais longos para as funções binárias e ternárias. Finalmente, esse estudo mostra que os sistemas contendo o diatômico relaxam-se predominantemente por mecanismos translacionais binários em modelos de solvatação envolvendo alterações apenas na polarizabilidade do soluto, e por mecanismos rotacionais atrativos binários em modelos envolvendo alterações no comprimento de ligação.
In the present work, we describe our results concerning our molecular dynamics investigation of the mechanical solvation dynamics within the linear response regime in model systems composed by liquid argon with a monoatomic or diatomic solute. The effect of molecular parameters (size, polarizability) and density has been elucidated for various solvation models. Time Correlation Functions for the solvation energy were calculated and separated into n-body (n = 2; 3) contributions distinguishing repulsive and attractive interactions in both liquid systems. In addition, we computed second time derivatives of these functions in order to describe translational, rotational, and roto-translational portions in the solutions containing the diatomics. We found that collective time correlation functions are well described by binary correlations at low liquid densities and, at high densities, ternary correlations become more important producing faster decaying collective time correlation functions due to partial cancellation effects. The repulsive and attractive time correlation functions exhibit a dynamic behavior that is independent on the solvation model due to linear scaling factors that only affect the absolute amplitudes of these functions. In general, the systems involving a rotational degree of freedom furnish smaller correlation times for the collective solvation dynamics, but stronger correlated two-body and three-body terms. Finally, this study shows that the solvation dynamics for the solution containing the diatomics relaxes predominatly by binary translational mechanisms when solvation models involving changes only in the polarizability parameter are considered. Binary attractive rotational mechanism become important in models with changes in the bond length.
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Rouhvand, Bahar. "Vesicle-Protein Diffusion and Interaction Study Using Time Resolved Fluorescence Correlation Spectroscopy." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1503261462042903.

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Books on the topic "Time correlation functions"

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Rubinstein, Robert. Effects of helicity on Lagrangian and Eulerian time correlations in turbulence. Hampton, VA: Institute for Computer Applications in Science and Engineering, NASA Langley Research Center, 1998.

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Cevelev, Aleksandr. Strategic development of railway transport logistics. ru: INFRA-M Academic Publishing LLC., 2021. http://dx.doi.org/10.12737/1194747.

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The monograph is devoted to the methodology of material and technical support of railway transport. According to the types of activities, the nature of the material and technical resources used, technologies, means and management systems, Russian railways belong to the category of high-tech industries that must have high quality and technical level, reliability and technological efficiency in operation. For this reason, the logistics system itself, both in structure and in the algorithm of the functions performed as a whole, needs a serious improvement in the quality of its work. The economic situation in Russia requires a revision of the principles and mechanisms of management based on the corporate model of supply chain management, focused on logistics knowledge. In the difficult economic conditions of the current decade, it is necessary to improve the quality of the supply organization of enterprises and structural divisions of railway transport, directly related to the implementation of the process approach, the advantage of which is a more detailed regulation of management actions and their mutual coordination. In order to increase the efficiency of its activities and develop the management system, Russian Railways is developing a lean production system aimed at further expanding the implementation of the principles of customer orientation, ideology and corporate culture. At the present time, the solution of many issues is impossible without a cybernetic approach to the formulation of problems of material and technical support and logistics analysis of information technologies, to the implementation of the developed algorithms and models of development strategies and concepts for improving the business processes of the production system. The management strategy, or the general plan for the implementation of activities for the management of material resources, is based on a fundamental assessment of the alignment and correlation of forces and factors operating in the economic and political field, taking into account the impact on the specific form of the management strategy. The materials will be useful to the heads and specialists of the directorates of the MTO, CDZs and can be used in the scientific research of bachelors, masters and postgraduates interested in the economics of railway transport and supply logistics.
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Allen, Michael P., and Dominic J. Tildesley. How to analyse the results. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198803195.003.0008.

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In this chapter, practical guidance is given on the calculation of thermodynamic, structural, and dynamical quantities from simulation trajectories. Program examples are provided to illustrate the calculation of the radial distribution function and a time correlation function using the direct and fast Fourier transform methods. There is a detailed discussion of the calculation of statistical errors through the statistical inefficiency. The estimation of the error in equilibrium averages, fluctuations and in time correlation functions is discussed. The correction of thermodynamic averages to neighbouring state points is described along with the extension and extrapolation of the radial distribution function. The calculation of transport coefficients by the integration of the time correlation function and through the Einstein relation is discussed.
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Morawetz, Klaus. Spectral Properties. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198797241.003.0008.

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The spectral properties of the nonequilibrium Green’s functions are explored. Causality and sum rules are shown to be completed by the extended quasiparticle picture. The off-shell motion is seen to become visible in satellite structures of the spectral function. Different forms of ansatz to reduce the two-time Green’s function to a one-time reduced density matrix are discussed with respect to the consistency to other approximations. We have seen from the information contained in the correlation function that the statistical weight of excitations with which the distributions are populated are given by the spectral function. This momentum-resolved density of state can be found by the retarded and advance functions.
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Morawetz, Klaus. Interacting Systems far from Equilibrium. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198797241.001.0001.

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In quantum statistics based on many-body Green’s functions, the effective medium is represented by the selfenergy. This book aims to discuss the selfenergy from this point of view. The knowledge of the exact selfenergy is equivalent to the knowledge of the exact correlation function from which one can evaluate any single-particle observable. Complete interpretations of the selfenergy are as rich as the properties of the many-body systems. It will be shown that classical features are helpful to understand the selfenergy, but in many cases we have to include additional aspects describing the internal dynamics of the interaction. The inductive presentation introduces the concept of Ludwig Boltzmann to describe correlations by the scattering of many particles from elementary principles up to refined approximations of many-body quantum systems. The ultimate goal is to contribute to the understanding of the time-dependent formation of correlations. Within this book an up-to-date most simple formalism of nonequilibrium Green’s functions is presented to cover different applications ranging from solid state physics (impurity scattering, semiconductor, superconductivity, Bose–Einstein condensation, spin-orbit coupled systems), plasma physics (screening, transport in magnetic fields), cold atoms in optical lattices up to nuclear reactions (heavy-ion collisions). Both possibilities are provided, to learn the quantum kinetic theory in terms of Green’s functions from the basics using experiences with phenomena, and experienced researchers can find a framework to develop and to apply the quantum many-body theory straight to versatile phenomena.
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Ferrari, Patrik L., and Herbert Spohn. Random matrices and Laplacian growth. Edited by Gernot Akemann, Jinho Baik, and Philippe Di Francesco. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780198744191.013.39.

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This article reviews the theory of random matrices with eigenvalues distributed in the complex plane and more general ‘beta ensembles’ (logarithmic gases in 2D). It first considers two ensembles of random matrices with complex eigenvalues: ensemble C of general complex matrices and ensemble N of normal matrices. In particular, it describes the Dyson gas picture for ensembles of matrices with general complex eigenvalues distributed on the plane. It then presents some general exact relations for correlation functions valid for any values of N and β before analysing the distribution and correlations of the eigenvalues in the large N limit. Using the technique of boundary value problems in two dimensions and elements of the potential theory, the article demonstrates that the finite-time blow-up (a cusp–like singularity) of the Laplacian growth with zero surface tension is a critical point of the normal and complex matrix models.
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Morawetz, Klaus. Transient Time Period. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198797241.003.0019.

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The formation of correlations at short- time scales is considered. A universal response function is found which allows describing the formation of collective modes in plasmas created by femto-second lasers as well as the formation of occupations in cold atomic optical lattices. Quantum quench and sudden switching of interactions are possible to describe by such Levinson-type kinetic equations on the transient time regime. On larger time scales it is shown that non-Markovian–Levnson equations double count correlations and the extended quasiparticle picture to distinguish between the reduced density matrix and quasiparticle distribution solve this shortcoming. The problem of initial correlations and how they can be incorporated into the Green’s function technique to result into modified kinetic equations is solved and a systematic expansion is suggested.
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Bradbury, Elizabeth J., and Nicholas D. James. Mapping of neurotrophin receptors on adult sensory neurons. Edited by Paul Farquhar-Smith, Pierre Beaulieu, and Sian Jagger. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198834359.003.0022.

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The paper discussed in this chapter describes the first mapping of neurotrophin receptors in adult sensory neurons. Neurotrophins and their receptors were a particularly hot topic at the time, but the primary focus of interest had been in their role in development. In this paper, McMahon and colleagues characterized both mRNA and protein expression of the recently discovered trk receptors on defined populations of adult sensory neurons, correlating trk expression with other primary afferent projection neuron properties such as cell size and neuronal function. Furthermore, by showing clear correlations between the expression of different trk receptors and the physical and functional properties of defined primary afferent projections, the authors provided key evidence suggesting that nerve growth factor and neurotrophin-3 acted on functionally distinct populations of adult sensory neurons. This paper provided the basis for subsequent research on neurotrophin signalling and function in both the healthy and the diseased nervous system.
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Berber, Stevan. Discrete Communication Systems. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198860792.001.0001.

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The book present essential theory and practice of the discrete communication systems design, based on the theory of discrete time stochastic processes, and their relation to the existing theory of digital communication systems. Using the notion of stochastic linear time invariant systems, in addition to the orhogonality principles, a general structure of the discrete communication system is constructed in terms of mathematical operators. Based on this structure, the MPSK, MFSK, QAM, OFDM and CDMA systems, using discrete modulation methods, are deduced as special cases. The signals are processed in the time and frequency domain, which requires precise derivatives of their amplitude spectral density functions, correlation functions and related energy and pover spectral densities. The book is self-sufficient, because it uses the unified notation both in the main ten chapters explaining communications systems theory and nine supplementary chapters dealing with the continuous and discrete time signal processing for both the deterministic and stochastic signals. In this context, the indexing of vital signals and finctions makes obvious distinction beteween them. Having in mind the controversial nature of the continuous time white Gaussian noise process, a separate chapter is dedicated to the noise discretisation by introducing notions of noise entropy and trauncated Gaussian density function to avoid limitations in applying the Nyquist criterion. The text of the book is acompained by the solutions of problems for all chapters and a set of deign projects with the defined projects’ topics and tasks and offered solutions.
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Ross, John, Igor Schreiber, and Marcel O. Vlad. Determination of Complex Reaction Mechanisms. Oxford University Press, 2006. http://dx.doi.org/10.1093/oso/9780195178685.001.0001.

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In a chemical system with many chemical species several questions can be asked: what species react with other species: in what temporal order: and with what results? These questions have been asked for over one hundred years about simple and complex chemical systems, and the answers constitute the macroscopic reaction mechanism. In Determination of Complex Reaction Mechanisms authors John Ross, Igor Schreiber, and Marcel Vlad present several systematic approaches for obtaining information on the causal connectivity of chemical species, on correlations of chemical species, on the reaction pathway, and on the reaction mechanism. Basic pulse theory is demonstrated and tested in an experiment on glycolysis. In a second approach, measurements on time series of concentrations are used to construct correlation functions and a theory is developed which shows that from these functions information may be inferred on the reaction pathway, the reaction mechanism, and the centers of control in that mechanism. A third approach is based on application of genetic algorithm methods to the study of the evolutionary development of a reaction mechanism, to the attainment given goals in a mechanism, and to the determination of a reaction mechanism and rate coefficients by comparison with experiment. Responses of non-linear systems to pulses or other perturbations are analyzed, and mechanisms of oscillatory reactions are presented in detail. The concluding chapters give an introduction to bioinformatics and statistical methods for determining reaction mechanisms.
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Book chapters on the topic "Time correlation functions"

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Schirmacher, Walter. "Time-Dependent Correlation and Response Functions." In Theory of Liquids and Other Disordered Media, 99–110. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-06950-0_7.

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Pecora, R. "Basic Concepts – Scattering and Time Correlation Functions." In Soft Matter Characterization, 2–40. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-4465-6_1.

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Berne, B. J., and G. D. Harp. "On the Calculation of Time Correlation Functions." In Advances in Chemical Physics, 63–227. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470143636.ch3.

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Sung, Wokyung. "Dynamic Linear Responses and Time Correlation Functions." In Graduate Texts in Physics, 327–46. Dordrecht: Springer Netherlands, 2018. http://dx.doi.org/10.1007/978-94-024-1584-1_17.

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Okabe, Yasunori. "On long time tails of correlation functions for KMO-Langevin equations." In Lecture Notes in Mathematics, 391–97. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/bfb0078497.

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Dufty, James W. "Time Correlation Functions and Hydrodynamic Modes for Lattice Gas Cellular Automata." In Microscopic Simulations of Complex Flows, 257–66. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4684-1339-7_18.

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Habicht, K., R. Golub, R. Gähler, and T. Keller. "Space-Time View of Neutron Spin Echo, Correlation Functions and Phonon Focusing." In Neutron Spin Echo Spectroscopy, 116–32. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/3-540-45823-9_11.

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Alonso, Daniel, and Inés Vega. "Timescales in Quantum Open Systems: Dynamics of Time Correlation Functions and Stochastic Quantum Trajectory Methods in Non-Markovian Systems." In Time in Quantum Mechanics II, 277–301. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-03174-8_10.

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Pesquera, L., and R. Blanco. "Gas Ring Lasers with Backscattering: One-Time Statistical Properties and Intensity Correlation Functions." In Coherence and Quantum Optics VI, 897–900. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4613-0847-8_163.

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Blinov, Nicholas, and Pierre-Nicholas Roy. "Rotations and Exchange in Doped Helium Clusters: Insight from Imaginary-Time Correlation Functions." In ACS Symposium Series, 165–75. Washington, DC: American Chemical Society, 2006. http://dx.doi.org/10.1021/bk-2007-0953.ch012.

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Conference papers on the topic "Time correlation functions"

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WEBER, Axel. "A generating functional for equal-time correlation functions." In VIIIth Conference Quark Confinement and the Hadron Spectrum. Trieste, Italy: Sissa Medialab, 2012. http://dx.doi.org/10.22323/1.077.0161.

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Weber, Axel. "Steps toward Dyson-Schwinger equations for equal-time correlation functions." In PARTICLES AND FIELDS. ASCE, 2009. http://dx.doi.org/10.1063/1.3131573.

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Evans, Allan K. "The long-time behavior of correlation functions in dynamical systems." In Stochastic and chaotic dynamics in the lakes. AIP, 2000. http://dx.doi.org/10.1063/1.1302412.

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Fishman, Louis, B. Lars G. Jonsson, Maarten V. de Hoop, Börje Nilsson, Louis Fishman, Anders Karlsson, and Sven Nordebo. "Time Reversal Mirrors and Cross Correlation Functions in Acoustic Wave Propagation." In MATHEMATICAL MODELING OF WAVE PHENOMENA: 3rd Conference on Mathematical Modeling of Wave Phenomena, 20th Nordic Conference on Radio Science and Communications. AIP, 2009. http://dx.doi.org/10.1063/1.3117094.

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Yu, F. T. S., and X. J. Lu. "Real-time programmable joint transform correlator." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1985. http://dx.doi.org/10.1364/oam.1985.the7.

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A real-time programmable joint transform correlator (PJTC) utilizing a magnetooptic device (MOD) with a liquid crystal light valve (LCLV) is presented. Object functions to be correlated are written into a light MOD with a programmable microcomputer as input signals. Real-time correlation takes place with a LCLV, as a square-law detector, with a coherent read out. Cross correlation between the input functions can be obtained through the inverse Fourier transform of the read-out coherent illumination. A brief discussion of the proposed PJTC and a few experimental results are provided.
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Leong, S. Y., Y. R. Zheng, and Chengshan Xiao. "Space-time fading correlation functions of a 3-D MIMO channel model." In 2004 IEEE Wireless Communications and Networking Conference (IEEE Cat. No.04TH8733). IEEE, 2004. http://dx.doi.org/10.1109/wcnc.2004.1311346.

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Wu, Tsan-Ming, and Chia-Ming Kuo. "3-D Space-Time-Frequency Correlation Functions of Mobile-to-Mobile Radio Channels." In 2007 IEEE 65th Vehicular Technology Conference. IEEE, 2007. http://dx.doi.org/10.1109/vetecs.2007.80.

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Korenkov, A., A. Dmitriev, and O. Astafiev. "Measurement system of correlation functions of microwave single photon source in real time." In FOURTH INTERNATIONAL CONFERENCE ON QUANTUM TECHNOLOGIES (ICQT-2017). Author(s), 2018. http://dx.doi.org/10.1063/1.5025446.

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LEMARCHAND, A., and C. BIANCA. "TIME ASYMMETRY OF CROSS-CORRELATION FUNCTIONS AS A SIGNATURE OF NON EQUILIBRIUM STEADY STATES." In International Symposium on Mathematical and Computational Biology. WORLD SCIENTIFIC, 2015. http://dx.doi.org/10.1142/9789814667944_0003.

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Alonso, Daniel, Ines de Vega, J. G. Hartnett, and P. C. Abbott. "Dynamics of time correlation functions and stochastic quantum trajectories methods in Non-Markovian systems." In FRONTIERS OF FUNDAMENTAL AND COMPUTATIONAL PHYSICS: 10th International Symposium. AIP, 2010. http://dx.doi.org/10.1063/1.3460217.

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Reports on the topic "Time correlation functions"

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Cao, Jianshu, and Gregory A. Voth. A Theory for Time Correlation Functions in Liquids. Fort Belvoir, VA: Defense Technical Information Center, May 1995. http://dx.doi.org/10.21236/ada294650.

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Cao, Jianshu, and Gregory A. Voth. Semiclassical Approximations to Quantum Dynamical Time Correlation Functions. Fort Belvoir, VA: Defense Technical Information Center, October 1995. http://dx.doi.org/10.21236/ada300432.

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Cao, Jianshu, and Gregory A. Voth. A New Perspective on Quantum Time Correlation Functions. Fort Belvoir, VA: Defense Technical Information Center, November 1993. http://dx.doi.org/10.21236/ada272579.

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Taniguchi, M., and P. R. Krishnaiah. Asymptotic Distributions of Functions of the Eigenvalues of the Sample Covariance Matrix and Canonical Correlation Matrix in Multivariate Time Series. Fort Belvoir, VA: Defense Technical Information Center, March 1986. http://dx.doi.org/10.21236/ada170282.

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Kuropiatnyk, D. I. Actuality of the problem of parametric identification of a mathematical model. [б. в.], December 2018. http://dx.doi.org/10.31812/123456789/2885.

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The purpose of the article is to study the possibilities of increasing the efficiency of a mathematical model by identifying the parameters of an object. A key factor for parametrization can be called the consideration of properties of the values of the model at a specific time point, which allows a deeper analysis of data dependencies and correlation between them. However, such a technique does not always work, because in advance it is impossible to predict that the parameters can be substantially optimized. In addition, it is necessary to take into account the fact that minimization reduces the values of parameters without taking into account their real physical properties. The correctness of the final values will be based on dynamically selected parameters, which allows you to modify the terms of use of the system in real time. In the development process, the values of experimentally obtained data with the model are compared, which allows you to understand the accuracy of minimization. When choosing the most relevant parameters, various minimization functions are used, which provides an opportunity to cover a wide range of theoretical initial situations. Verification of the correctness of the decision is carried out with the help of a quality function, which can identify the accuracy and correctness of the optimized parameters. It is possible to choose different types of functional quality, depending on the characteristics of the initial data. The presence of such tools during parametrization allows for varied analysis of the model, testing it on various algorithms, data volumes and conditions of guaranteed convergence of functional methods.
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Moran, Nava, Richard Crain, and Wolf-Dieter Reiter. Regulation by Light of Plant Potassium Uptake through K Channels: Biochemical, Physiological and Biophysical Study. United States Department of Agriculture, September 1995. http://dx.doi.org/10.32747/1995.7571356.bard.

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The swelling of plant motor cells is regulated by various signals with almost unknown mediators. One of the obligatory steps in the signaling cascade is the activation of K+-influx channels -K+ channels activated by hyperpolarization (KH channels). We thus explored the regulation of these channels in our model system, motor cell protoplasts from Samanea saman, using patch-clamp in the "whole cell" configuration. (a) The most novel finding was that the activity of KH channels in situ varied with the time of the day, in positive correlation with cell swelling: in Extensor cells KH channels were active in the earlier part of the day, while in Flexor cells only during the later part of the day; (b) High internal pH promoted the activity of these channels in Extensor cells, opposite to the behavior of the equivalent channels in guard cells, but in conformity with the predicted behavior of the putative KH channel, cloned from S. saman recently; (c) HIgh external K+ concentration increased (KH channel currents in Flexor cells. BL depolarized the Flexor cells, as detected in cell-attached patch-clamp recording, using KD channels (the K+-efflux channels) as "voltage-sensing devices". Subsequent Red-Light (RL) pulse followed by Darkness, hyperpolarized the cell. We attribute these changes to the inhibition of the H+-pump by BL and its reactivation by RL, as they were abolished by an H+-pump inhibitor. BL increased also the activity KD channels, in a voltage-independent manner - in all probability by an independent signaling pathway. Blue-Light (BL), which stimulates shrinking of Flexor cells, evoked the IP3 signaling cascade (detected directly by IP3 binding assay), known to mobilize cytosolic Ca2+. Nevertheless, cytosolic Ca2+ . did not activate the KD channel in excised, inside-out patches. In this study we established a close functional similarity of the KD channels between Flexor and Extensior cells. Thus the differences in their responses must stem from different links to signaling in both cell types.
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Pichersky, Eran, Alexander Vainstein, and Natalia Dudareva. Scent biosynthesis in petunia flowers under normal and adverse environmental conditions. United States Department of Agriculture, January 2014. http://dx.doi.org/10.32747/2014.7699859.bard.

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The ability of flowering plants to prosper throughout evolution, and for many crop plants to set fruit, is strongly dependent on their ability to attract pollinators. To that end many plants synthesize a spectrum of volatile compounds in their flowers. Scent is a highly dynamic trait that is strongly influenced by the environment. However, with high temperature conditions becoming more common, the molecular interplay between this type of stress and scent biosynthesis need to be investigated. Using petunia as a model system, our project had three objectives: (1) Determine the expression patterns of genes encoding biosynthetic scent genes (BSGs) and of several genes previously identified as encoding transcription factors involved in scent regulation under normal and elevated temperature conditions. (2) Examine the function of petunia transcription factors and a heterologous transcription factor, PAPl, in regulating genes of the phenylpropanoid/benzenoid scent pathway. (3) Study the mechanism of transcriptional regulation by several petunia transcription factors and PAPl of scent genes under normal and elevated temperature conditions by examining the interactions between these transcription factors and the promoters of target genes. Our work accomplished the first two goals but was unable to complete the third goal because of lack of time and resources. Our general finding was that when plants grew at higher temperatures (28C day/22C night, vs. 22C/16C), their scent emission decreased in general, with the exception of a few volatiles such as vanillin. To understand why, we looked at gene transcription levels, and saw that generally there was a good correlation between levels of transcriptions of gene specifying enzymes for specific scent compounds and levels of emission of the corresponding scent compounds. Enzyme activity levels, however, showed little difference between plants growing at different temperature regimes. Plants expressing the heterologous gene PAPl showed general increase in scent emission in control temperature conditions but emission decreased at the higher temperature conditions, as seen for control plants. Finally, expression of several transcription factor genes decreased at high temperature, but expression of new transcription factor, EOB-V, increased, implicating it in the decrease of transcription of BSGs. The major conclusion of this work is that high temperature conditions negatively affect scent emission from plants, but that some genetic engineering approaches could ameliorate this problem.
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Russo, David, and William A. Jury. Characterization of Preferential Flow in Spatially Variable Unsaturated Field Soils. United States Department of Agriculture, October 2001. http://dx.doi.org/10.32747/2001.7580681.bard.

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Preferential flow appears to be the rule rather than the exception in field soils and should be considered in the quantitative description of solute transport in the unsaturated zone of heterogeneous formations on the field scale. This study focused on both experimental monitoring and computer simulations to identify important features of preferential flow in the natural environment. The specific objectives of this research were: (1) To conduct dye tracing and multiple tracer experiments on undisturbed field plots to reveal information about the flow velocity, spatial prevalence, and time evolution of a preferential flow event; (2) To conduct numerical experiments to determine (i) whether preferential flow observations are consistent with the Richards flow equation; and (ii) whether volume averaging over a domain experiencing preferential flow is possible; (3) To develop a stochastic or a transfer function model that incorporates preferential flow. Regarding our field work, we succeeded to develop a new method for detecting flow patterns faithfully representing the movement of water flow paths in structured and non-structured soils. The method which is based on application of ammonium carbonate was tested in a laboratory study. Its use to detect preferential flow was also illustrated in a field experiment. It was shown that ammonium carbonate is a more conservative tracer of the water front than the popular Brilliant Blue. In our detailed field experiments we also succeeded to document the occurrence of preferential flow during soil water redistribution following the cessation of precipitation in several structureless field soils. Symptoms of the unstable flow observed included vertical fingers 20 - 60 cm wide, isolated patches, and highly concentrated areas of the tracers in the transmission zone. Soil moisture and tracer measurements revealed that the redistribution flow became fingered following a reversal of matric potential gradient within the wetted area. Regarding our simulation work, we succeeded to develop, implement and test a finite- difference, numerical scheme for solving the equations governing flow and transport in three-dimensional, heterogeneous, bimodal, flow domains with highly contrasting soil materials. Results of our simulations demonstrated that under steady-state flow conditions, the embedded clay lenses (with very low conductivity) in bimodal formations may induce preferential flow, and, consequently, may enhance considerably both the solute spreading and the skewing of the solute breakthrough curves. On the other hand, under transient flow conditions associated with substantial redistribution periods with diminishing water saturation, the effect of the embedded clay lenses on the flow and the transport might diminish substantially. Regarding our stochastic modeling effort, we succeeded to develop a theoretical framework for flow and transport in bimodal, heterogeneous, unsaturated formations, based on a stochastic continuum presentation of the flow and a general Lagrangian description of the transport. Results of our analysis show that, generally, a bimodal distribution of the formation properties, characterized by a relatively complex spatial correlation structure, contributes to the variability in water velocity and, consequently, may considerably enhance solute spreading. This applies especially in formations in which: (i) the correlation length scales and the variances of the soil properties associated with the embedded soil are much larger than those of the background soil; (ii) the contrast between mean properties of the two subdomains is large; (iii) mean water saturation is relatively small; and (iv) the volume fraction of the flow domain occupied by the embedded soil is relatively large.
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Brosh, Arieh, David Robertshaw, Yoav Aharoni, Zvi Holzer, Mario Gutman, and Amichai Arieli. Estimation of Energy Expenditure of Free Living and Growing Domesticated Ruminants by Heart Rate Measurement. United States Department of Agriculture, April 2002. http://dx.doi.org/10.32747/2002.7580685.bard.

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Research objectives were: 1) To study the effect of diet energy density, level of exercise, thermal conditions and reproductive state on cardiovascular function as it relates to oxygen (O2) mobilization. 2) To validate the use of heart rate (HR) to predict energy expenditure (EE) of ruminants, by measuring and calculating the energy balance components at different productive and reproductive states. 3) To validate the use of HR to identify changes in the metabolizable energy (ME) and ME intake (MEI) of grazing ruminants. Background: The development of an effective method for the measurement of EE is essential for understanding the management of both grazing and confined feedlot animals. The use of HR as a method of estimating EE in free-ranging large ruminants has been limited by the availability of suitable field monitoring equipment and by the absence of empirical understanding of the relationship between cardiac function and metabolic rate. Recent developments in microelectronics provide a good opportunity to use small HR devices to monitor free-range animals. The estimation of O2 uptake (VO2) of animals from their HR has to be based upon a consistent relationship between HR and VO2. The question as to whether, or to what extent, feeding level, environmental conditions and reproductive state affect such a relationship is still unanswered. Studies on the basic physiology of O2 mobilization (in USA) and field and feedlot-based investigations (in Israel) covered a , variety of conditions in order to investigate the possibilities of using HR to estimate EE. In USA the physiological studies conducted using animals with implanted flow probes, show that: I) although stroke volume decreases during intense exercise, VO2 per one heart beat per kgBW0.75 (O2 Pulse, O2P) actually increases and measurement of EE by HR and constant O2P may underestimate VO2unless the slope of the regression relating to heart rate and VO2 is also determined, 2) alterations in VO2 associated with the level of feeding and the effects of feeding itself have no effect on O2P, 3) both pregnancy and lactation may increase blood volume, especially lactation; but they have no effect on O2P, 4) ambient temperature in the range of 15 to 25°C in the resting animal has no effect on O2P, and 5) severe heat stress, induced by exercise, elevates body temperature to a sufficient extent that 14% of cardiac output may be required to dissipate the heat generated by exercise rather than for O2 transport. However, this is an unusual situation and its affect on EE estimation in a freely grazing animal, especially when heart rate is monitored over several days, is minor. In Israel three experiments were carried out in the hot summer to define changes in O2P attributable to changes in the time of day or In the heat load. The animals used were lambs and young calves in the growing phase and highly yielding dairy cows. In the growing animals the time of day, or the heat load, affected HR and VO2, but had no effect on O2P. On the other hand, the O2P measured in lactating cows was affected by the heat load; this is similar to the finding in the USA study of sheep. Energy balance trials were conducted to compare MEI recovery by the retained energy (RE) and by EE as measured by HR and O2P. The trial hypothesis was that if HR reliably estimated EE, the MEI proportion to (EE+RE) would not be significantly different from 1.0. Beef cows along a year of their reproductive cycle and growing lambs were used. The MEI recoveries of both trials were not significantly different from 1.0, 1.062+0.026 and 0.957+0.024 respectively. The cows' reproductive state did not affect the O2P, which is similar to the finding in the USA study. Pasture ME content and animal variables such as HR, VO2, O2P and EE of cows on grazing and in confinement were measured throughout three years under twenty-nine combinations of herbage quality and cows' reproductive state. In twelve grazing states, individual faecal output (FO) was measured and MEI was calculated. Regression analyses of the EE and RE dependent on MEI were highly significant (P<0.001). The predicted values of EE at zero intake (78 kcal/kgBW0.75), were similar to those estimated by NRC (1984). The EE at maintenance condition of the grazing cows (EE=MEI, 125 kcal/kgBW0.75) which are in the range of 96.1 to 125.5 as presented by NRC (1996 pp 6-7) for beef cows. Average daily HR and EE were significantly increased by lactation, P<0.001 and P<0.02 respectively. Grazing ME significantly increased HR and EE, P<0.001 and P<0.00l respectively. In contradiction to the finding in confined ewes and cows, the O2P of the grazing cows was significantly affected by the combined treatments (P<0.00l ); this effect was significantly related to the diet ME (P<0.00l ) and consequently to the MEI (P<0.03). Grazing significantly increased O2P compared to confinement. So, when EE of grazing animals during a certain season of the year is estimated using the HR method, the O2P must be re measured whenever grazing ME changes. A high correlation (R2>0.96) of group average EE and of HR dependency on MEI was also found in confined cows, which were fed six different diets and in growing lambs on three diets. In conclusion, the studies conducted in USA and in Israel investigated in depth the physiological mechanisms of cardiovascular and O2 mobilization, and went on to investigate a wide variety of ruminant species, ages, reproductive states, diets ME, time of intake and time of day, and compared these variables under grazing and confinement conditions. From these combined studies we can conclude that EE can be determined from HR measurements during several days, multiplied by O2P measured over a short period of time (10-15 min). The study showed that RE could be determined during the growing phase without slaughtering. In the near future the development microelectronic devices will enable wide use of the HR method to determine EE and energy balance. It will open new scopes of physiological and agricultural research with minimizes strain on animals. The method also has a high potential as a tool for herd management.
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Wideman, Jr., Robert F., Nicholas B. Anthony, Avigdor Cahaner, Alan Shlosberg, Michel Bellaiche, and William B. Roush. Integrated Approach to Evaluating Inherited Predictors of Resistance to Pulmonary Hypertension Syndrome (Ascites) in Fast Growing Broiler Chickens. United States Department of Agriculture, December 2000. http://dx.doi.org/10.32747/2000.7575287.bard.

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Background PHS (pulmonary hypertension syndrome, ascites syndrome) is a serious cause of loss in the broiler industry, and is a prime example of an undesirable side effect of successful genetic development that may be deleteriously manifested by factors in the environment of growing broilers. Basically, continuous and pinpointed selection for rapid growth in broilers has led to higher oxygen demand and consequently to more frequent manifestation of an inherent potential cardiopulmonary incapability to sufficiently oxygenate the arterial blood. The multifaceted causes and modifiers of PHS make research into finding solutions to the syndrome a complex and multi threaded challenge. This research used several directions to better understand the development of PHS and to probe possible means of achieving a goal of monitoring and increasing resistance to the syndrome. Research Objectives (1) To evaluate the growth dynamics of individuals within breeding stocks and their correlation with individual susceptibility or resistance to PHS; (2) To compile data on diagnostic indices found in this work to be predictive for PHS, during exposure to experimental protocols known to trigger PHS; (3) To conduct detailed physiological evaluations of cardiopulmonary function in broilers; (4) To compile data on growth dynamics and other diagnostic indices in existing lines selected for susceptibility or resistance to PHS; (5) To integrate growth dynamics and other diagnostic data within appropriate statistical procedures to provide geneticists with predictive indices that characterize resistance or susceptibility to PHS. Revisions In the first year, the US team acquired the costly Peckode weigh platform / individual bird I.D. system that was to provide the continuous (several times each day), automated weighing of birds, for a comprehensive monitoring of growth dynamics. However, data generated were found to be inaccurate and irreproducible, so making its use implausible. Henceforth, weighing was manual, this highly labor intensive work precluding some of the original objectives of using such a strategy of growth dynamics in selection procedures involving thousands of birds. Major conclusions, solutions, achievements 1. Healthy broilers were found to have greater oscillations in growth velocity and acceleration than PHS susceptible birds. This proved the scientific validity of our original hypothesis that such differences occur. 2. Growth rate in the first week is higher in PHS-susceptible than in PHS-resistant chicks. Artificial neural network accurately distinguished differences between the two groups based on growth patterns in this period. 3. In the US, the unilateral pulmonary occlusion technique was used in collaboration with a major broiler breeding company to create a commercial broiler line that is highly resistant to PHS induced by fast growth and low ambient temperatures. 4. In Israel, lines were obtained by genetic selection on PHS mortality after cold exposure in a dam-line population comprising of 85 sire families. The wide range of PHS incidence per family (0-50%), high heritability (about 0.6), and the results in cold challenged progeny, suggested a highly effective and relatively easy means for selection for PHS resistance 5. The best minimally-invasive diagnostic indices for prediction of PHS resistance were found to be oximetry, hematocrit values, heart rate and electrocardiographic (ECG) lead II waves. Some differences in results were found between the US and Israeli teams, probably reflecting genetic differences in the broiler strains used in the two countries. For instance the US team found the S wave amplitude to predict PHS susceptibility well, whereas the Israeli team found the P wave amplitude to be a better valid predictor. 6. Comprehensive physiological studies further increased knowledge on the development of PHS cardiopulmonary characteristics of pre-ascitic birds, pulmonary arterial wedge pressures, hypotension/kidney response, pulmonary hemodynamic responses to vasoactive mediators were all examined in depth. Implications, scientific and agricultural Substantial progress has been made in understanding the genetic and environmental factors involved in PHS, and their interaction. The two teams each successfully developed different selection programs, by surgical means and by divergent selection under cold challenge. Monitoring of the progress and success of the programs was done be using the in-depth estimations that this research engendered on the reliability and value of non-invasive predictive parameters. These findings helped corroborate the validity of practical means to improve PHT resistance by research-based programs of selection.
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