WorldWideScience

Sample records for simple ecological theory

  1. Theory of simple liquids

    CERN Document Server

    Hansen, Jean-Pierre

    1986-01-01

    This book gives a comprehensive and up-to-date treatment of the theory of ""simple"" liquids. The new second edition has been rearranged and considerably expanded to give a balanced account both of basic theory and of the advances of the past decade. It presents the main ideas of modern liquid state theory in a way that is both pedagogical and self-contained. The book should be accessible to graduate students and research workers, both experimentalists and theorists, who have a good background in elementary mechanics.Key Features* Compares theoretical deductions with experimental r

  2. Some directions in ecological theory.

    Science.gov (United States)

    Kendall, Bruce E

    2015-12-01

    The role of theory within ecology has changed dramatically in recent decades. Once primarily a source of qualitative conceptual framing, ecological theories and models are now often used to develop quantitative explanations of empirical patterns and to project future dynamics of specific ecological systems. In this essay, I recount my own experience of this transformation, in which accelerating computing power and the widespread incorporation of stochastic processes into ecological theory combined to create some novel integration of mathematical and statistical models. This stronger integration drives theory towards incorporating more biological realism, and I explore ways in which we can grapple with that realism to generate new general theoretical insights. This enhanced realism, in turn, may lead to frameworks for projecting ecological responses to anthropogenic change, which is, arguably, the central challenge for 21st-century ecology. In an era of big data and synthesis, ecologists are increasingly seeking to infer causality from observational data; but conventional biometry provides few tools for this project. This is a realm where theorists can and should play an important role, and I close by pointing towards some analytical and philosophical approaches developed in our sister discipline of economics that address this very problem. While I make no grand prognostications about the likely discoveries of ecological theory over the coming century, you will find in this essay a scattering of more or less far-fetched ideas that I, at least, think are interesting and (possibly) fruitful directions for our field.

  3. Linking Statistical and Ecological Theory

    NARCIS (Netherlands)

    Harris, Keith; Parsons, Todd L.; Ijaz, Umer Z.; Lahti, Leo; Holmes, Ian; Quince, Christopher

    2017-01-01

    Neutral models which assume ecological equivalence between species provide null models for community assembly. In Hubbell's unified neutral theory of biodiversity (UNTB), many local communities are connected to a single metacommunity through differing immigration rates. Our ability to fit the

  4. Game theory and plant ecology.

    Science.gov (United States)

    McNickle, Gordon G; Dybzinski, Ray

    2013-04-01

    The fixed and plastic traits possessed by a plant, which may be collectively thought of as its strategy, are commonly modelled as density-independent adaptations to its environment. However, plant strategies may also represent density- or frequency-dependent adaptations to the strategies used by neighbours. Game theory provides the tools to characterise such density- and frequency-dependent interactions. Here, we review the contributions of game theory to plant ecology. After briefly reviewing game theory from the perspective of plant ecology, we divide our review into three sections. First, game theoretical models of allocation to shoots and roots often predict investment in those organs beyond what would be optimal in the absence of competition. Second, game theoretical models of enemy defence suggest that an individual's investment in defence is not only a means of reducing its own tissue damage but also a means of deflecting enemies onto competitors. Finally, game theoretical models of trade with mutualistic partners suggest that the optimal trade may reflect competition for access to mutualistic partners among plants. In short, our review provides an accessible entrance to game theory that will help plant ecologists enrich their research with its worldview and existing predictions. © 2013 Blackwell Publishing Ltd/CNRS.

  5. The role of ecological theory in microbial ecology.

    Science.gov (United States)

    Prosser, James I; Bohannan, Brendan J M; Curtis, Tom P; Ellis, Richard J; Firestone, Mary K; Freckleton, Rob P; Green, Jessica L; Green, Laura E; Killham, Ken; Lennon, Jack J; Osborn, A Mark; Solan, Martin; van der Gast, Christopher J; Young, J Peter W

    2007-05-01

    Microbial ecology is currently undergoing a revolution, with repercussions spreading throughout microbiology, ecology and ecosystem science. The rapid accumulation of molecular data is uncovering vast diversity, abundant uncultivated microbial groups and novel microbial functions. This accumulation of data requires the application of theory to provide organization, structure, mechanistic insight and, ultimately, predictive power that is of practical value, but the application of theory in microbial ecology is currently very limited. Here we argue that the full potential of the ongoing revolution will not be realized if research is not directed and driven by theory, and that the generality of established ecological theory must be tested using microbial systems.

  6. Aspects of an ecological theory of language

    DEFF Research Database (Denmark)

    Bang, J. C.; Trampe, W.

    2014-01-01

    Our aim and knowledge-constitutive interest is to identify some central aspects of an ecological theory of language. In our understanding of building an integrative ecological theory of language, it seems useful to look first for roots of a special ecological understanding of language. Here...

  7. Bayesian decision theory : A simple toy problem

    NARCIS (Netherlands)

    van Erp, H.R.N.; Linger, R.O.; van Gelder, P.H.A.J.M.

    2016-01-01

    We give here a comparison of the expected outcome theory, the expected utility theory, and the Bayesian decision theory, by way of a simple numerical toy problem in which we look at the investment willingness to avert a high impact low probability event. It will be found that for this toy problem

  8. Some empirical evidence for ecological dissonance theory.

    Science.gov (United States)

    Miller, D I; Verhoek-Miller, N; Giesen, J M; Wells-Parker, E

    2000-04-01

    Using Festinger's cognitive dissonance theory as a model, the extension to Barker's ecological theory, referred to as ecological dissonance theory, was developed. Designed to examine the motivational dynamics involved when environmental systems are in conflict with each other or with cognitive systems, ecological dissonance theory yielded five propositions which were tested in 10 studies. This summary of the studies suggests operationally defined measures of ecological dissonance may correlate with workers' satisfaction with their jobs, involvement with their jobs, alienation from their work, and to a lesser extent, workers' conflict resolution behavior and communication style.

  9. Ecological Restoration: Guidance from Theory

    Directory of Open Access Journals (Sweden)

    Joy Zedler

    2005-09-01

    Full Text Available A review of the science and practice of ecosystem restoration led me to identify key ecological theories and concepts that are relevant to planning, implementing, and sustaining restoration efforts. From experience with actual restoration projects, I provide guidance for improving the restoration process. Despite an abundance of theory and guidance, restoration goals are not always achieved, and pathways toward targets are not highly predictable. This is understandable, since each restoration project has many constraints and unique challenges. To improve restoration progress, I advise that sites be designed as experiments to allow learning while doing. At least the larger projects can be restored in phases, each designed as experimental treatments to test alternative restoration approaches. Subsequent phases can then adopt one or more of the treatments that best achieved goals in earlier phases while applying new tests of other restoration measures. Both science and restoration can progress simultaneously. This phased, experimental approach (called “adaptive restoration” is an effective tool for improving restoration when monitoring, assessment, interpretation and research are integrated into the process.

  10. Clipboard Simple laboratory tests of ecological theories

    Indian Academy of Sciences (India)

    Madhu

    ... with understanding the mechanisms behind the maintenance of, and fluctu- ... Various mathematical functions have been developed that try to capture the most ... This method has an obvious drawback as the underlying assumptions of the ...

  11. Crisis in Context Theory: An Ecological Model

    Science.gov (United States)

    Myer, Rick A.; Moore, Holly B.

    2006-01-01

    This article outlines a theory for understanding the impact of a crisis on individuals and organizations. Crisis in context theory (CCT) is grounded in an ecological model and based on literature in the field of crisis intervention and on personal experiences of the authors. A graphic representation denotes key components and premises of CCT,…

  12. Drift estimation from a simple field theory

    International Nuclear Information System (INIS)

    Mendes, F. M.; Figueiredo, A.

    2008-01-01

    Given the outcome of a Wiener process, what can be said about the drift and diffusion coefficients? If the process is stationary, these coefficients are related to the mean and variance of the position displacements distribution. However, if either drift or diffusion are time-dependent, very little can be said unless some assumption about that dependency is made. In Bayesian statistics, this should be translated into some specific prior probability. We use Bayes rule to estimate these coefficients from a single trajectory. This defines a simple, and analytically tractable, field theory.

  13. Civic ecology practices: insights from practice theory

    Directory of Open Access Journals (Sweden)

    Marianne E. Krasny

    2015-06-01

    Full Text Available Our aim was to explore the use of practice theory as an approach to studying urban environmental stewardship. Urban environmental stewardship, or civic ecology practice, contributes to ecosystem services and community well-being and has been studied using social-ecological systems resilience, property rights, communities of practice, and governance frameworks. Practice theory, which previously has been applied in studies of consumer behaviors, adds a new perspective to urban stewardship research, focusing on how elements of a practice, such as competencies, meanings, and physical resource, together define the practice. We applied practice theory to eight different civic ecology practices, including oyster gardening in New York City, a civil society group engaged in litter cleanup in Iran, and village grove restoration in South Korea. Our analysis suggests that in applying practice theory to the civic ecology context, consideration should be given to social and communication competencies, how meanings can motivate volunteers and sustain practice, and the nature of the resource that is being stewarded. Future studies may want to focus on how practice elements interact within and vary across practices and may be used to more systematically analyze and share ideas among diverse civic ecology practices.

  14. Optimized theory for simple and molecular fluids.

    Science.gov (United States)

    Marucho, M; Montgomery Pettitt, B

    2007-03-28

    An optimized closure approximation for both simple and molecular fluids is presented. A smooth interpolation between Perkus-Yevick and hypernetted chain closures is optimized by minimizing the free energy self-consistently with respect to the interpolation parameter(s). The molecular version is derived from a refinement of the method for simple fluids. In doing so, a method is proposed which appropriately couples an optimized closure with the variant of the diagrammatically proper integral equation recently introduced by this laboratory [K. M. Dyer et al., J. Chem. Phys. 123, 204512 (2005)]. The simplicity of the expressions involved in this proposed theory has allowed the authors to obtain an analytic expression for the approximate excess chemical potential. This is shown to be an efficient tool to estimate, from first principles, the numerical value of the interpolation parameters defining the aforementioned closure. As a preliminary test, representative models for simple fluids and homonuclear diatomic Lennard-Jones fluids were analyzed, obtaining site-site correlation functions in excellent agreement with simulation data.

  15. Hollow Ecology: Ecological Modernization Theory and the Death of Nature

    Directory of Open Access Journals (Sweden)

    Jeffrey A. Ewing

    2017-02-01

    Full Text Available The last few decades have seen the rise of ‘ecological modernization theory’ (EMT as a “green capitalist” tradition extending modernization theory into environmental sociology. This article uses a synthesis of political economy, world-systems theory, and political, economic, and environmental sociology to demonstrate that the EMT presumption of growth and profit as economic priorities (alongside its neglect of core-periphery relations produces many feedback loops which fatally undermine the viability of EMT’s own political, technological, and social prescriptions, alongside creating problems for the fundamental EMT concept of ‘ecological rationality.’ Furthermore, this article attempts to explain why “green capitalist” approaches to environmental analysis have influence within policy and social science circles despite their inadequacies within environmental sociology. Finally, this article argues that in order to address the ecological challenges of our era, environmental sociology needs to reject “green capitalist” traditions like ‘ecological modernization theory’ which presuppose the desirability and maintenance of profit and growth as economic priorities (and predominantly fail to critique power imbalances between core and non-core nations, and instead return to the development of traditions willing to critique the fundamental traits of the capitalist world-system.

  16. Simple recursion relations for general field theories

    International Nuclear Information System (INIS)

    Cheung, Clifford; Shen, Chia-Hsien; Trnka, Jaroslav

    2015-01-01

    On-shell methods offer an alternative definition of quantum field theory at tree-level, replacing Feynman diagrams with recursion relations and interaction vertices with a handful of seed scattering amplitudes. In this paper we determine the simplest recursion relations needed to construct a general four-dimensional quantum field theory of massless particles. For this purpose we define a covering space of recursion relations which naturally generalizes all existing constructions, including those of BCFW and Risager. The validity of each recursion relation hinges on the large momentum behavior of an n-point scattering amplitude under an m-line momentum shift, which we determine solely from dimensional analysis, Lorentz invariance, and locality. We show that all amplitudes in a renormalizable theory are 5-line constructible. Amplitudes are 3-line constructible if an external particle carries spin or if the scalars in the theory carry equal charge under a global or gauge symmetry. Remarkably, this implies the 3-line constructibility of all gauge theories with fermions and complex scalars in arbitrary representations, all supersymmetric theories, and the standard model. Moreover, all amplitudes in non-renormalizable theories without derivative interactions are constructible; with derivative interactions, a subset of amplitudes is constructible. We illustrate our results with examples from both renormalizable and non-renormalizable theories. Our study demonstrates both the power and limitations of recursion relations as a self-contained formulation of quantum field theory.

  17. [Basic theory and research method of urban forest ecology].

    Science.gov (United States)

    He, Xingyuan; Jin, Yingshan; Zhu, Wenquan; Xu, Wenduo; Chen, Wei

    2002-12-01

    With the development of world economy and the increment of urban population, the urban environment problem hinders the urban sustainable development. Now, more and more people realized the importance of urban forests in improving the quality of urban ecology. Therefore, a new subject, urban forest ecology, and correlative new concept frame in the field formed. The theoretic foundation of urban forest ecology derived from the mutual combination of theory relating to forest ecology, landscape ecology, landscape architecture ecology and anthrop-ecology. People survey the development of city from the view of ecosystem, and regard the environment, a colony of human, animals and plants, as main factors of the system. The paper introduces systematically the urban forest ecology as follows: 1) the basic concept of urban forest ecology; 2) the meaning of urban forest ecology; 3) the basic principle and theoretic base of urban forest ecology; 4) the research method of urban forest ecology; 5) the developmental expectation of urban forest ecology.

  18. Testing theory in practice: a simple experiment

    NARCIS (Netherlands)

    Terpstra, R.; Brezocnik, Z.; Kapus, T.; Ferreira Pires, Luis; Heerink, A.W.; Tretmans, G.J.

    1996-01-01

    In this paper we discuss the experiences gained in conducting a simple testing experiment. The goal of this experiment is to apply the abstract, formal testing framework [8] in a practical setting, and to indicate the critical aspects in its application to realistic testing situations. For that

  19. A simple theory of linear mode conversion

    International Nuclear Information System (INIS)

    Cairns, R.A.; Lashmore-Davies, C.N.; Woods, A.M.

    1984-01-01

    A summary is given of the basic theory of linear mode conversion involving the construction of differential equations for the mode amplitudes based on the properties of the dispersion relation in the neighbourhood of the mode conversion point. As an example the transmission coefficient for tunneling from the upper hybrid resonance through the evanescent region to the adjacent cut-off is treated. 7 refs, 3 figs

  20. Quantum Decision Theory in Simple Risky Choices.

    Science.gov (United States)

    Favre, Maroussia; Wittwer, Amrei; Heinimann, Hans Rudolf; Yukalov, Vyacheslav I; Sornette, Didier

    2016-01-01

    Quantum decision theory (QDT) is a recently developed theory of decision making based on the mathematics of Hilbert spaces, a framework known in physics for its application to quantum mechanics. This framework formalizes the concept of uncertainty and other effects that are particularly manifest in cognitive processes, which makes it well suited for the study of decision making. QDT describes a decision maker's choice as a stochastic event occurring with a probability that is the sum of an objective utility factor and a subjective attraction factor. QDT offers a prediction for the average effect of subjectivity on decision makers, the quarter law. We examine individual and aggregated (group) data, and find that the results are in good agreement with the quarter law at the level of groups. At the individual level, it appears that the quarter law could be refined in order to reflect individual characteristics. This article revisits the formalism of QDT along a concrete example and offers a practical guide to researchers who are interested in applying QDT to a dataset of binary lotteries in the domain of gains.

  1. Quantum Decision Theory in Simple Risky Choices

    Science.gov (United States)

    Favre, Maroussia; Wittwer, Amrei; Heinimann, Hans Rudolf; Yukalov, Vyacheslav I.; Sornette, Didier

    2016-01-01

    Quantum decision theory (QDT) is a recently developed theory of decision making based on the mathematics of Hilbert spaces, a framework known in physics for its application to quantum mechanics. This framework formalizes the concept of uncertainty and other effects that are particularly manifest in cognitive processes, which makes it well suited for the study of decision making. QDT describes a decision maker’s choice as a stochastic event occurring with a probability that is the sum of an objective utility factor and a subjective attraction factor. QDT offers a prediction for the average effect of subjectivity on decision makers, the quarter law. We examine individual and aggregated (group) data, and find that the results are in good agreement with the quarter law at the level of groups. At the individual level, it appears that the quarter law could be refined in order to reflect individual characteristics. This article revisits the formalism of QDT along a concrete example and offers a practical guide to researchers who are interested in applying QDT to a dataset of binary lotteries in the domain of gains. PMID:27936217

  2. Applied statistics in ecology: common pitfalls and simple solutions

    Science.gov (United States)

    E. Ashley Steel; Maureen C. Kennedy; Patrick G. Cunningham; John S. Stanovick

    2013-01-01

    The most common statistical pitfalls in ecological research are those associated with data exploration, the logic of sampling and design, and the interpretation of statistical results. Although one can find published errors in calculations, the majority of statistical pitfalls result from incorrect logic or interpretation despite correct numerical calculations. There...

  3. Evolutionary game theory and organizational ecology: The case of resource-partitioning theory

    OpenAIRE

    ZHOU, Chaohong; VAN WITTELOOSTUIJN, Arjen

    2009-01-01

    Abstract: In this paper, we construct a mathematical model that applies tools from evolutionary game theory to issues in organizational ecology. Evolutionary game theory shares the key feature of mathematical rigor with the industrial organization tradition, but is similar to organizational ecology by emphasizing evolutionary dynamics. Evolutionary game theory may well be a complementary modeling tool for the analytical study of organizational ecology issues, next to formal logic, standard ga...

  4. Explicating Practicum Program Theory: A Case Example in Human Ecology

    Science.gov (United States)

    Chandler, Kathryn M. M.; Williamson, Deanna L.

    2013-01-01

    This study explicated the theory underpinning the Human Ecology Practicum Program offered in the Department of Human Ecology at the University of Alberta. The program has operated for 40 years but never been formally evaluated. Using a document analysis, focus group and individual interviews, and a stakeholder working group, we explored…

  5. Theory of simple liquids with applications to soft matter

    CERN Document Server

    Hansen, Jean-Pierre

    2013-01-01

    Comprehensive coverage of topics in the theory of classical liquids Widely regarded as the standard text in its field, Theory of Simple Liquids gives an advanced but self-contained account of liquid state theory within the unifying framework provided by classical statistical mechanics. The structure of this revised and updated Fourth Edition is similar to that of the previous one but there are significant shifts in emphasis and much new material has been added. Major changes and Key Features in content include: Expansion of existing sections on simulation methods, liquid-vapour coexisten

  6. A simple formula for the conserved charges of soliton theories

    International Nuclear Information System (INIS)

    Ferreira, Luiz Agostinho; Zakrzewski, Wojtek J.

    2007-01-01

    We present a simple formula for all the conserved charges of soliton theories, evaluated on the solutions belonging to the orbit of the vacuum under the group of dressing transformations. For pedagogical reasons we perform the explicit calculations for the case of the sine-Gordon model, taken as a prototype of soliton theories. We show that the energy and momentum are boundary terms for all the solutions on the orbit of the vacuum. That orbit includes practically all the solutions of physical interest, namely solitons, multi-solitons, breathers, and combinations of solitons and breathers. The example of the mKdV equation is also given explicitly

  7. Are ecological and evolutionary theories scientific?

    Science.gov (United States)

    Murray, B G

    2001-05-01

    Scientists observe nature, search for generalizations, and provide explanations for why the world is as it is. Generalizations are of two kinds. The first are descriptive and inductive, such as Boyle's Law. They are derived from observations and therefore refer to observables (in this case, pressure and volume). The second are often imaginative and form the axioms of a deductive theory, such as Newton's Laws of Motion. They often refer to unobservables (e.g. inertia and gravitation). Biology has many inductive generalizations (e.g. Bergmann's Rule and 'all cells arise from preexisting cells') but few, if any, recognized universal laws and virtually no deductive theory. Many biologists and philosophers of biology have agreed that predictive theory is inappropriate in biology, which is said to be more complex than physics, and that one can have nonpredictive explanations, such as the neo-Darwinian Theory of Evolution by Natural Selection. Other philosophers dismiss nonpredictive, explanatory theories, including evolutionary 'theory', as metaphysics. Most biologists do not think of themselves as philosophers or give much thought to the philosophical basis of their research. Nevertheless, their philosophy shows in the way they do research. The plethora of ad hoc (i.e. not universal) hypotheses indicates that biologists are reluctant inductivists in that the search for generalization does not have a high priority. Biologists test their hypotheses by verification. Theoretical physicists, in contrast, are deductive unifiers and test their explanatory hypotheses by falsification. I argue that theoretical biology (concerned with unobservables, such as fitness and natural selection) is not scientific because it lacks universal laws and predictive theory. In order to make this argument, I review the differences between verificationism and falsificationism, induction and deduction, and descriptive and explanatory laws. I show how these differ with a specific example of a

  8. Ecological and Social Dynamics in Simple Models of Ecosystem Management

    Directory of Open Access Journals (Sweden)

    Stephen R. Carpenter

    1999-12-01

    Full Text Available Simulation models were developed to explore and illustrate dynamics of socioecological systems. The ecosystem is a lake subject to phosphorus pollution. Phosphorus flows from agriculture to upland soils, to surface waters, where it cycles between water and sediments. The ecosystem is multistable, and moves among domains of attraction depending on the history of pollutant inputs. The alternative states yield different economic benefits. Agents form expectations about ecosystem dynamics, markets, and/or the actions of managers, and choose levels of pollutant inputs accordingly. Agents have heterogeneous beliefs and/or access to information. Their aggregate behavior determines the total rate of pollutant input. As the ecosystem changes, agents update their beliefs and expectations about the world they co-create, and modify their actions accordingly. For a wide range of scenarios, we observe irregular oscillations among ecosystem states and patterns of agent behavior. These oscillations resemble some features of the adaptive cycle of panarchy theory.

  9. Basics of theory of ecological crisis management

    Directory of Open Access Journals (Sweden)

    Stajić Ljubomir

    2013-01-01

    Full Text Available Today, it is clear that environmental accidents and processes represent, not only potential but also real causes of crises on which states must be aware of. The formation of the ecological crisis is growing exponentially, along with their consequences. The problem with the environmental crisisis lies not in the fact that they exist, but how we treat them. Exploring the causes of the crisis requires an interdisciplinary approach. At the micro level, this approach focuses on the role of individuals. At the middle level of research, focus is on organizational factors and processes that may play important role in causing the crisis. Macro level of approach lists possible causes that seem to make the crisis more or less inevitable and unavoidable features of the modern world. The crisis is also characterized by negative effects (perturbations, deregulation, conflict, confused action, intense stress, which leads to reckless actions and positive effects (mobilization, solidarity, cooperation, improved adaptation to the environment, experiential learning. Furthermore, ecological crisis represents an emergency situation whose beginning and duration are not predetermined. Anti-crisis measures have failed mainly because of the numerous factors influencing on one hand, on a complexity of the crisis and, on the other hand, because of its continuously changing factors throughout the duration of the crisis. Managing ecological crisis occurs, therefore, as a permanently professional inventive and complicated process which aims to prevent the escalation of the crisis, as well as the elimination of the expected and actual negative consequences of the crisis. Mismanagement of such crisis drains system resources, interferes with its function and organization, impacts on the financial opportunities while achieving positive goals. Extreme mismanagement can lead to the entropy of the system itself. The purpose of this paper is to elaborate basic facts of managing

  10. A non–extensive thermodynamic theory of ecological systems

    International Nuclear Information System (INIS)

    Xuan, Le Van; Ngoc, Nguyen Khac; Lan, Nguyen Tri; Viet, Nguyen Ai

    2017-01-01

    After almost 30 years of development, it is not controversial issue that the so–called Tsallis entropy provides a useful approach to studying the complexity where the non–additivity of the systems under consideration is frequently met. Also, in the ecological research, Tsallis entropy, or in other words, q –entropy has been found itself as a generalized approach to define a range of diversity indices including Shannon–Wiener and Simpson indices. As a further stage of development in theoretical research, a thermodynamic theory based on Tsallis entropy or diversity indices in ecology has to be constructed for ecological systems to provide knowledge of ecological macroscopic behaviors. The standard method of theoretical physics is used in the manipulation and the equivalence between phenomenological thermodynamics and ecological aspects is the purpose of the ongoing research. The present work is in the line of the authors research to implement Tsallis non–extensivity approach to obtain the most important thermodynamic quantities of ecological systems such as internal energy U q and temperature T q based on a given modeled truncated Boltzmann distribution of the Whittaker plot for a dataset. These quantities have their own ecological meaning, especially the temperature T q provides the insight of equilibrium condition among ecological systems as it is well–known in 0th law of thermodynamics. (paper)

  11. A non-extensive thermodynamic theory of ecological systems

    Science.gov (United States)

    Van Xuan, Le; Khac Ngoc, Nguyen; Lan, Nguyen Tri; Viet, Nguyen Ai

    2017-06-01

    After almost 30 years of development, it is not controversial issue that the so-called Tsallis entropy provides a useful approach to studying the complexity where the non-additivity of the systems under consideration is frequently met. Also, in the ecological research, Tsallis entropy, or in other words, q-entropy has been found itself as a generalized approach to define a range of diversity indices including Shannon-Wiener and Simpson indices. As a further stage of development in theoretical research, a thermodynamic theory based on Tsallis entropy or diversity indices in ecology has to be constructed for ecological systems to provide knowledge of ecological macroscopic behaviors. The standard method of theoretical physics is used in the manipulation and the equivalence between phenomenological thermodynamics and ecological aspects is the purpose of the ongoing research. The present work is in the line of the authors research to implement Tsallis non-extensivity approach to obtain the most important thermodynamic quantities of ecological systems such as internal energy Uq and temperature Tq based on a given modeled truncated Boltzmann distribution of the Whittaker plot for a dataset. These quantities have their own ecological meaning, especially the temperature Tq provides the insight of equilibrium condition among ecological systems as it is well-known in 0th law of thermodynamics.

  12. Unifying ecology and macroevolution with individual-based theory.

    Science.gov (United States)

    Rosindell, James; Harmon, Luke J; Etienne, Rampal S

    2015-05-01

    A contemporary goal in both ecology and evolutionary biology is to develop theory that transcends the boundary between the two disciplines, to understand phenomena that cannot be explained by either field in isolation. This is challenging because macroevolution typically uses lineage-based models, whereas ecology often focuses on individual organisms. Here, we develop a new parsimonious individual-based theory by adding mild selection to the neutral theory of biodiversity. We show that this model generates realistic phylogenies showing a slowdown in diversification and also improves on the ecological predictions of neutral theory by explaining the occurrence of very common species. Moreover, we find the distribution of individual fitness changes over time, with average fitness increasing at a pace that depends positively on community size. Consequently, large communities tend to produce fitter species than smaller communities. These findings have broad implications beyond biodiversity theory, potentially impacting, for example, invasion biology and paleontology. © 2015 The Authors. Ecology Letters published by John Wiley & Sons Ltd and CNRS.

  13. Spectral theory and nonlinear analysis with applications to spatial ecology

    CERN Document Server

    Cano-Casanova, S; Mora-Corral , C

    2005-01-01

    This volume details some of the latest advances in spectral theory and nonlinear analysis through various cutting-edge theories on algebraic multiplicities, global bifurcation theory, non-linear Schrödinger equations, non-linear boundary value problems, large solutions, metasolutions, dynamical systems, and applications to spatial ecology. The main scope of the book is bringing together a series of topics that have evolved separately during the last decades around the common denominator of spectral theory and nonlinear analysis - from the most abstract developments up to the most concrete applications to population dynamics and socio-biology - in an effort to fill the existing gaps between these fields.

  14. Fixing All Moduli in a Simple F-Theory Compactification

    International Nuclear Information System (INIS)

    Denef, F.

    2005-01-01

    We discuss a simple example of an F-theory compactification on a Calabi-Yau fourfold where background fluxes, together with nonperturbative effects from Euclidean D3 instantons and gauge dynamics on D7 branes, allow us to fix all closed and open string moduli. We explicitly check that the known higher order corrections to the potential, which we neglect in our leading approximation, only shift the results by a small amount. In our exploration of the model, we encounter interesting new phenomena, including examples of transitions where D7 branes absorb O3 planes, while changing topology to preserve the net D3 charge

  15. Leveraging ecological theory to guide natural product discovery.

    Science.gov (United States)

    Smanski, Michael J; Schlatter, Daniel C; Kinkel, Linda L

    2016-03-01

    Technological improvements have accelerated natural product (NP) discovery and engineering to the point that systematic genome mining for new molecules is on the horizon. NP biosynthetic potential is not equally distributed across organisms, environments, or microbial life histories, but instead is enriched in a number of prolific clades. Also, NPs are not equally abundant in nature; some are quite common and others markedly rare. Armed with this knowledge, random 'fishing expeditions' for new NPs are increasingly harder to justify. Understanding the ecological and evolutionary pressures that drive the non-uniform distribution of NP biosynthesis provides a rational framework for the targeted isolation of strains enriched in new NP potential. Additionally, ecological theory leads to testable hypotheses regarding the roles of NPs in shaping ecosystems. Here we review several recent strain prioritization practices and discuss the ecological and evolutionary underpinnings for each. Finally, we offer perspectives on leveraging microbial ecology and evolutionary biology for future NP discovery.

  16. School Psychology Research: Combining Ecological Theory and Prevention Science

    Science.gov (United States)

    Burns, Matthew K.

    2011-01-01

    The current article comments on the importance of theoretical implications within school psychological research, and proposes that ecological theory and prevention science could provide the conceptual framework for school psychology research and practice. Articles published in "School Psychology Review" should at least discuss potential…

  17. Unifying ecology and macroevolution with individual-based theory

    NARCIS (Netherlands)

    Rosindell, James; Harmon, Luke J.; Etienne, Rampal S.

    A contemporary goal in both ecology and evolutionary biology is to develop theory that transcends the boundary between the two disciplines, to understand phenomena that cannot be explained by either field in isolation. This is challenging because macroevolution typically uses lineage-based models,

  18. Developing interprofessional education online: An ecological systems theory analysis.

    Science.gov (United States)

    Bluteau, Patricia; Clouder, Lynn; Cureton, Debra

    2017-07-01

    This article relates the findings of a discourse analysis of an online asynchronous interprofessional learning initiative involving two UK universities. The impact of the initiative is traced over three intensive periods of online interaction, each of several-weeks duration occurring over a three-year period, through an analysis of a random sample of discussion forum threads. The corpus of rich data drawn from the forums is interpreted using ecological systems theory, which highlights the complexity of interaction of individual, social and cultural elements. Ecological systems theory adopts a life course approach to understand how development occurs through processes of progressively more complex reciprocal interaction between people and their environment. This lens provides a novel approach for analysis and interpretation of findings with respect to the impact of pre-registration interprofessional education and the interaction between the individual and their social and cultural contexts as they progress through 3/4 years of their programmes. Development is mapped over time (the chronosystem) to highlight the complexity of interaction across microsystems (individual), mesosystems (curriculum and institutional/care settings), exosystems (community/wider local context), and macrosystems (national context and culture). This article illustrates the intricacies of students' interprofessional development over time and the interactive effects of social ecological components in terms of professional knowledge and understanding, wider appreciation of health and social care culture and identity work. The implications for contemporary pre-registration interprofessional education and the usefulness and applicability of ecological systems theory for future research and development are considered.

  19. From the Neutral Theory to a Comprehensive and Multiscale Theory of Ecological Equivalence.

    Science.gov (United States)

    Munoz, François; Huneman, Philippe

    2016-09-01

    The neutral theory of biodiversity assumes that coexisting organisms are equally able to survive, reproduce, and disperse (ecological equivalence), but predicts that stochastic fluctuations of these abilities drive diversity dynamics. It predicts remarkably well many biodiversity patterns, although substantial evidence for the role of niche variation across organisms seems contradictory. Here, we discuss this apparent paradox by exploring the meaning and implications of ecological equivalence. We address the question whether neutral theory provides an explanation for biodiversity patterns and acknowledges causal processes. We underline that ecological equivalence, although central to neutral theory, can emerge at local and regional scales from niche-based processes through equalizing and stabilizing mechanisms. Such emerging equivalence corresponds to a weak conception of neutral theory, as opposed to the assumption of strict equivalence at the individual level in strong conception. We show that this duality is related to diverging views on hypothesis testing and modeling in ecology. In addition, the stochastic dynamics exposed in neutral theory are pervasive in ecological systems and, rather than a null hypothesis, ecological equivalence is best understood as a parsimonious baseline to address biodiversity dynamics at multiple scales.

  20. Ecological theories of systems and contextual change in medical education.

    Science.gov (United States)

    Ellaway, Rachel H; Bates, Joanna; Teunissen, Pim W

    2017-12-01

    Contemporary medical practice is subject to many kinds of change, to which both individuals and systems have to respond and adapt. Many medical education programmes have their learners rotating through different training contexts, which means that they too must learn to adapt to contextual change. Contextual change presents many challenges to medical education scholars and practitioners, not least because of a somewhat fractured and contested theoretical basis for responding to these challenges. There is a need for robust concepts to articulate and connect the various debates on contextual change in medical education. Ecological theories of systems encompass a range of concepts of how and why systems change and how and why they respond to change. The use of these concepts has the potential to help medical education scholars explore the nature of change and understand the role it plays in affording as well as limiting teaching and learning. This paper, aimed at health professional education scholars and policy makers, explores a number of key concepts from ecological theories of systems to present a comprehensive model of contextual change in medical education to inform theory and practice in all areas of medical education. The paper considers a range of concepts drawn from ecological theories of systems, including biotic and abiotic factors, panarchy, attractors and repellers, basins of attraction, homeostasis, resilience, adaptability, transformability and hysteresis. Each concept is grounded in practical examples from medical education. Ecological theories of systems consider change and response in terms of adaptive cycles functioning at different scales and speeds. This can afford opportunities for systematic consideration of responses to contextual change in medical education, which in turn can inform the design of education programmes, activities, evaluations, assessments and research that accommodates the dynamics and consequences of contextual change.

  1. Ecological Modernisation Theory and Industrialising Economies : The Case of Viet Nam

    NARCIS (Netherlands)

    Frijns, J.; Phuong Thuy Phung,; Mol, A.P.J.

    2000-01-01

    As Ecological Modernisation Theory has been developed against the background of European industrialised societies, the value and applicability of Ecological Modernisation Theory for developing or industrialising economies is often questioned. This article explores this controversy by taking Viet Nam

  2. Protected areas as social-ecological systems: perspectives from resilience and social-ecological systems theory.

    Science.gov (United States)

    Cumming, Graeme S; Allen, Craig R

    2017-09-01

    Conservation biology and applied ecology increasingly recognize that natural resource management is both an outcome and a driver of social, economic, and ecological dynamics. Protected areas offer a fundamental approach to conserving ecosystems, but they are also social-ecological systems whose ecological management and sustainability are heavily influenced by people. This editorial, and the papers in the invited feature that it introduces, discuss three emerging themes in social-ecological systems approaches to understanding protected areas: (1) the resilience and sustainability of protected areas, including analyses of their internal dynamics, their effectiveness, and the resilience of the landscapes within which they occur; (2) the relevance of spatial context and scale for protected areas, including such factors as geographic connectivity, context, exchanges between protected areas and their surrounding landscapes, and scale dependency in the provision of ecosystem services; and (3) efforts to reframe what protected areas are and how they both define and are defined by the relationships of people and nature. These emerging themes have the potential to transform management and policy approaches for protected areas and have important implications for conservation, in both theory and practice. © 2017 by the Ecological Society of America.

  3. A simple extrapolation of thermodynamic perturbation theory to infinite order

    International Nuclear Information System (INIS)

    Ghobadi, Ahmadreza F.; Elliott, J. Richard

    2015-01-01

    Recent analyses of the third and fourth order perturbation contributions to the equations of state for square well spheres and Lennard-Jones chains show trends that persist across orders and molecular models. In particular, the ratio between orders (e.g., A 3 /A 2 , where A i is the ith order perturbation contribution) exhibits a peak when plotted with respect to density. The trend resembles a Gaussian curve with the peak near the critical density. This observation can form the basis for a simple recursion and extrapolation from the highest available order to infinite order. The resulting extrapolation is analytic and therefore cannot fully characterize the critical region, but it remarkably improves accuracy, especially for the binodal curve. Whereas a second order theory is typically accurate for the binodal at temperatures within 90% of the critical temperature, the extrapolated result is accurate to within 99% of the critical temperature. In addition to square well spheres and Lennard-Jones chains, we demonstrate how the method can be applied semi-empirically to the Perturbed Chain - Statistical Associating Fluid Theory (PC-SAFT)

  4. The Operation Method of Smarter City Based on Ecological Theory

    Science.gov (United States)

    Fan, C.; Fan, H. Y.

    2017-10-01

    As the city and urbanization’s accelerated pace has caused galloping population, the urban framework is extending with increasingly complex social problems. The urban management tends to become complicated and the governance seems more difficult to pursue. exploring the urban management’s new model has attracted local governments’ urgent attention. tcombines the guiding ideology and that management’s practices based on ecological theory, explains the Smarter city Ecology Managementmodel’s formation, makes modern urban management’s comparative analysis and further defines the aforesaid management mode’s conceptual model. Based on the smarter city system theory’s ecological carrying capacity, the author uses mathematical model to prove the coordination relationship between the smarter city Ecology Managementmode’s subsystems, demonstrates that it can improve the urban management’s overall level, emphasizes smarter city management integrity, believing that urban system’s optimization is based on each subsystem being optimized, attaching the importance to elements, structure, and balance between each subsystem and between internal elements. Through the establishment of the smarter city Ecology Managementmodel’s conceptual model and theoretical argumentation, it provides a theoretical basis and technical guidance to that model’s innovation.

  5. Protected areas as social-ecological systems: perspectives from resilience and social-ecological systems theory

    Science.gov (United States)

    Cumming, Graeme S.; Allen, Craig R.

    2017-01-01

    Conservation biology and applied ecology increasingly recognize that natural resource management is both an outcome and a driver of social, economic, and ecological dynamics. Protected areas offer a fundamental approach to conserving ecosystems, but they are also social-ecological systems whose ecological management and sustainability are heavily influenced by people. This editorial, and the papers in the invited feature that it introduces, discuss three emerging themes in social-ecological systems approaches to understanding protected areas: (1) the resilience and sustainability of protected areas, including analyses of their internal dynamics, their effectiveness, and the resilience of the landscapes within which they occur; (2) the relevance of spatial context and scale for protected areas, including such factors as geographic connectivity, context, exchanges between protected areas and their surrounding landscapes, and scale dependency in the provision of ecosystem services; and (3) efforts to reframe what protected areas are and how they both define and are defined by the relationships of people and nature. These emerging themes have the potential to transform management and policy approaches for protected areas and have important implications for conservation, in both theory and practice.

  6. Langevin theory of anomalous Brownian motion made simple

    International Nuclear Information System (INIS)

    Tothova, Jana; Vasziova, Gabriela; Lisy, VladimIr; Glod, Lukas

    2011-01-01

    During the century from the publication of the work by Einstein (1905 Ann. Phys. 17 549) Brownian motion has become an important paradigm in many fields of modern science. An essential impulse for the development of Brownian motion theory was given by the work of Langevin (1908 C. R. Acad. Sci., Paris 146 530), in which he proposed an 'infinitely more simple' description of Brownian motion than that by Einstein. The original Langevin approach has however strong limitations, which were rigorously stated after the creation of the hydrodynamic theory of Brownian motion (1945). Hydrodynamic Brownian motion is a special case of 'anomalous Brownian motion', now intensively studied both theoretically and in experiments. We show how some general properties of anomalous Brownian motion can be easily derived using an effective method that allows one to convert the stochastic generalized Langevin equation into a deterministic Volterra-type integro-differential equation for the mean square displacement of the particle. Within the Gibbs statistics, the method is applicable to linear equations of motion with any kind of memory during the evolution of the system. We apply it to memoryless Brownian motion in a harmonic potential well and to Brownian motion in fluids, taking into account the effects of hydrodynamic memory. Exploring the mathematical analogy between Brownian motion and electric circuits, which are at nanoscales also described by the generalized Langevin equation, we calculate the fluctuations of charge and current in RLC circuits that are in contact with the thermal bath. Due to the simplicity of our approach it could be incorporated into graduate courses of statistical physics. Once the method is established, it allows bringing to the attention of students and effectively solving a number of attractive problems related to Brownian motion.

  7. A simple theory of LET spectra of heavy ion beams

    International Nuclear Information System (INIS)

    Wilson, J.W.; Townsend, L.W.; Schimmerling, W.; Norbury, J.W.; Wong, M.; Badavi, F.

    1985-01-01

    The transition of high energy ion beams through extended matter is of considerable interest to the space program as well as radiobiology and medical therapy. The transition is defined in terms of various atomic/molecular and nuclear cross sections in a Boltzmann-like equation. One dimensional solutions are derived herein from which LET spectra are derived for secondary fragments. Such LET spectra are fundamental to the evaluation of beam quality, biological effects, and radiation shield effectiveness. Sensitivity of LET spectral distributions to uncertainty in physical parameters such as the isotopic fragmentation parameters, fragment mass, and absorption cross section is established for a number of ion beams. The main limitation in LET studies is the paucity of both elemental and isotopic fragmentation data. The elemental fragmentation data is more readily available because of its simple experimental procedures. It has been suggested by some that natural abundance ratios should be used with the elemental cross sections but this leads to an order-of-magnitude error in LET spectra in many cases. Very few examples of isotopic fragmentation measurements are available. Although major advances in nuclear fragmentation theory have been made, we must await more extensive isotopic fragmentation experiments for final validation

  8. A simple model of bipartite cooperation for ecological and organizational networks.

    Science.gov (United States)

    Saavedra, Serguei; Reed-Tsochas, Felix; Uzzi, Brian

    2009-01-22

    In theoretical ecology, simple stochastic models that satisfy two basic conditions about the distribution of niche values and feeding ranges have proved successful in reproducing the overall structural properties of real food webs, using species richness and connectance as the only input parameters. Recently, more detailed models have incorporated higher levels of constraint in order to reproduce the actual links observed in real food webs. Here, building on previous stochastic models of consumer-resource interactions between species, we propose a highly parsimonious model that can reproduce the overall bipartite structure of cooperative partner-partner interactions, as exemplified by plant-animal mutualistic networks. Our stochastic model of bipartite cooperation uses simple specialization and interaction rules, and only requires three empirical input parameters. We test the bipartite cooperation model on ten large pollination data sets that have been compiled in the literature, and find that it successfully replicates the degree distribution, nestedness and modularity of the empirical networks. These properties are regarded as key to understanding cooperation in mutualistic networks. We also apply our model to an extensive data set of two classes of company engaged in joint production in the garment industry. Using the same metrics, we find that the network of manufacturer-contractor interactions exhibits similar structural patterns to plant-animal pollination networks. This surprising correspondence between ecological and organizational networks suggests that the simple rules of cooperation that generate bipartite networks may be generic, and could prove relevant in many different domains, ranging from biological systems to human society.

  9. A simple proof of orientability in colored group field theory.

    Science.gov (United States)

    Caravelli, Francesco

    2012-01-01

    Group field theory is an emerging field at the boundary between Quantum Gravity, Statistical Mechanics and Quantum Field Theory and provides a path integral for the gluing of n-simplices. Colored group field theory has been introduced in order to improve the renormalizability of the theory and associates colors to the faces of the simplices. The theory of crystallizations is instead a field at the boundary between graph theory and combinatorial topology and deals with n-simplices as colored graphs. Several techniques have been introduced in order to study the topology of the pseudo-manifold associated to the colored graph. Although of the similarity between colored group field theory and the theory of crystallizations, the connection between the two fields has never been made explicit. In this short note we use results from the theory of crystallizations to prove that color in group field theories guarantees orientability of the piecewise linear pseudo-manifolds associated to each graph generated perturbatively. Colored group field theories generate orientable pseudo-manifolds. The origin of orientability is the presence of two interaction vertices in the action of colored group field theories. In order to obtain the result, we made the connection between the theory of crystallizations and colored group field theory.

  10. Ecology

    International Nuclear Information System (INIS)

    Kalusche, D.

    1978-01-01

    The book turns to the freshment, the teacher, for preparation of ecological topics for lessons, but also to pupils of the secondary stage II, and the main course ecology. The book was knowingly held simple with the restriction to: the ecosystem and its abiotic basic functions, simple articles on population biology, bioceonotic balance ith the questions of niche formation and the life form types coherent with it, of the substance and energy household, the production biology and space-wise and time-wise differentations within an ecological system form the main points. A central role in the volume is given to the illustrations. Their variety is to show and deepen the coherences shown. (orig./HP) [de

  11. Galois and simple current symmetries in conformal field theory

    International Nuclear Information System (INIS)

    Schweigert, C.

    1995-01-01

    In this thesis various aspects of rational field theories are studied. In part I explicit examples for N=2 superconformal field theories are constructed by means of the coset approach. By means of these models string vacua are constructed, and the massless spectra of the string compactifications based on these models are computed. The symmetry of the S matrix, which implements the modular transformation on the space of characters is the subject of Part II. The developed methods are applied to the fusion rings of WZW theories. (HSI)

  12. Building Better Ecological Machines: Complexity Theory and Alternative Economic Models

    Directory of Open Access Journals (Sweden)

    Jess Bier

    2016-12-01

    Full Text Available Computer models of the economy are regularly used to predict economic phenomena and set financial policy. However, the conventional macroeconomic models are currently being reimagined after they failed to foresee the current economic crisis, the outlines of which began to be understood only in 2007-2008. In this article we analyze the most prominent of this reimagining: Agent-Based models (ABMs. ABMs are an influential alternative to standard economic models, and they are one focus of complexity theory, a discipline that is a more open successor to the conventional chaos and fractal modeling of the 1990s. The modelers who create ABMs claim that their models depict markets as ecologies, and that they are more responsive than conventional models that depict markets as machines. We challenge this presentation, arguing instead that recent modeling efforts amount to the creation of models as ecological machines. Our paper aims to contribute to an understanding of the organizing metaphors of macroeconomic models, which we argue is relevant conceptually and politically, e.g., when models are used for regulatory purposes.

  13. MaxEnt-Based Ecological Theory: A Template for Integrated Catchment Theory

    Science.gov (United States)

    Harte, J.

    2017-12-01

    The maximum information entropy procedure (MaxEnt) is both a powerful tool for inferring least-biased probability distributions from limited data and a framework for the construction of complex systems theory. The maximum entropy theory of ecology (METE) describes remarkably well widely observed patterns in the distribution, abundance and energetics of individuals and taxa in relatively static ecosystems. An extension to ecosystems undergoing change in response to disturbance or natural succession (DynaMETE) is in progress. I describe the structure of both the static and the dynamic theory and show a range of comparisons with census data. I then propose a generalization of the MaxEnt approach that could provide a framework for a predictive theory of both static and dynamic, fully-coupled, eco-socio-hydrological catchment systems.

  14. the Simple Centern Projection of SU (2) Gauge Theory

    NARCIS (Netherlands)

    Bakker, B.L.G.; Veselov, A.I.; Zubkov, M.A.

    2001-01-01

    We consider the SU(2) lattice gauge model. We propose a new gauge invariant definition of center projection, which we call the Simple Center Projection. We demonstrate the center dominance, i.e., the coincidence of the projected potential with the full potential up to the mass renormalization term

  15. Description and validation of the Simple, Efficient, Dynamic, Global, Ecological Simulator (SEDGES v.1.0)

    Science.gov (United States)

    Paiewonsky, Pablo; Elison Timm, Oliver

    2018-03-01

    In this paper, we present a simple dynamic global vegetation model whose primary intended use is auxiliary to the land-atmosphere coupling scheme of a climate model, particularly one of intermediate complexity. The model simulates and provides important ecological-only variables but also some hydrological and surface energy variables that are typically either simulated by land surface schemes or else used as boundary data input for these schemes. The model formulations and their derivations are presented here, in detail. The model includes some realistic and useful features for its level of complexity, including a photosynthetic dependency on light, full coupling of photosynthesis and transpiration through an interactive canopy resistance, and a soil organic carbon dependence for bare-soil albedo. We evaluate the model's performance by running it as part of a simple land surface scheme that is driven by reanalysis data. The evaluation against observational data includes net primary productivity, leaf area index, surface albedo, and diagnosed variables relevant for the closure of the hydrological cycle. In this setup, we find that the model gives an adequate to good simulation of basic large-scale ecological and hydrological variables. Of the variables analyzed in this paper, gross primary productivity is particularly well simulated. The results also reveal the current limitations of the model. The most significant deficiency is the excessive simulation of evapotranspiration in mid- to high northern latitudes during their winter to spring transition. The model has a relative advantage in situations that require some combination of computational efficiency, model transparency and tractability, and the simulation of the large-scale vegetation and land surface characteristics under non-present-day conditions.

  16. Toward a Simple Molecular Theory of Hydrophobic Hydration.

    Czech Academy of Sciences Publication Activity Database

    Jirsák, Jan; Škvor, J.; Nezbeda, Ivo

    2014-01-01

    Roč. 189, SI (2014), s. 13-19 ISSN 0167-7322 R&D Projects: GA AV ČR IAA200760905 Institutional support: RVO:67985858 Keywords : perturbation theory * primitive models * hydrophobic hydration Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 2.515, year: 2014

  17. Theory analysis and simple calculation of travelling wave burnup scheme

    International Nuclear Information System (INIS)

    Zhang Jian; Yu Hong; Gang Zhi

    2012-01-01

    Travelling wave burnup scheme is a new burnup scheme that breeds fuel locally just before it burns. Based on the preliminary theory analysis, the physical imagine was found. Through the calculation of a R-z cylinder travelling wave reactor core with ERANOS code system, the basic physical characteristics of this new burnup scheme were concluded. The results show that travelling wave reactor is feasible in physics, and there are some good features in the reactor physics. (authors)

  18. A simple test of expected utility theory using professional traders.

    Science.gov (United States)

    List, John A; Haigh, Michael S

    2005-01-18

    We compare behavior across students and professional traders from the Chicago Board of Trade in a classic Allais paradox experiment. Our experiment tests whether independence, a necessary condition in expected utility theory, is systematically violated. We find that both students and professionals exhibit some behavior consistent with the Allais paradox, but the data pattern does suggest that the trader population falls prey to the Allais paradox less frequently than the student population.

  19. Simple Theory of Thermal Fatigue Caused by RF Pulse Heating

    CERN Document Server

    Kuzikov, S

    2004-01-01

    The projects of electron-positron linear colliders imply that accelerating structures and other RF components will undergo action of extremely high RF fields. Except for breakdown threat there is an effect of the damage due to multi-pulse mechanical stress caused by Ohmic heating of the skin layer. A new theory of the thermal fatigue is considered. The theory is based on consideration of the quasi-elastic interaction between neighbor grains of metal due to the expansion of the thermal skin-layer. The developed theory predicts a total number of the RF pulses needed for surface degradation in dependence on temperature rise, pulse duration, and average temperature. The unknown coefficients in the final formula were found, using experimental data obtained at 11.4 GHz for the copper. In order to study the thermal fatigue at higher frequencies and to compare experimental and theoretical results, the experimental investigation of degradation of the copper cavity exposed to 30 GHz radiation is carried out now, basing...

  20. A simple theory of motor protein kinetics and energetics. II.

    Science.gov (United States)

    Qian, H

    2000-01-10

    A three-state stochastic model of motor protein [Qian, Biophys. Chem. 67 (1997) pp. 263-267] is further developed to illustrate the relationship between the external load on an individual motor protein in aqueous solution with various ATP concentrations and its steady-state velocity. A wide variety of dynamic motor behavior are obtained from this simple model. For the particular case of free-load translocation being the most unfavorable step within the hydrolysis cycle, the load-velocity curve is quasi-linear, V/Vmax = (cF/Fmax-c)/(1-c), in contrast to the hyperbolic relationship proposed by A.V. Hill for macroscopic muscle. Significant deviation from the linearity is expected when the velocity is less than 10% of its maximal (free-load) value--a situation under which the processivity of motor diminishes and experimental observations are less certain. We then investigate the dependence of load-velocity curve on ATP (ADP) concentration. It is shown that the free load Vmax exhibits a Michaelis-Menten like behavior, and the isometric Fmax increases linearly with ln([ATP]/[ADP]). However, the quasi-linear region is independent of the ATP concentration, yielding an apparently ATP-independent maximal force below the true isometric force. Finally, the heat production as a function of ATP concentration and external load are calculated. In simple terms and solved with elementary algebra, the present model provides an integrated picture of biochemical kinetics and mechanical energetics of motor proteins.

  1. Towards a simple mathematical theory of citation distributions.

    Science.gov (United States)

    Katchanov, Yurij L

    2015-01-01

    The paper is written with the assumption that the purpose of a mathematical theory of citation is to explain bibliometric regularities at the level of mathematical formalism. A mathematical formalism is proposed for the appearance of power law distributions in social citation systems. The principal contributions of this paper are an axiomatic characterization of citation distributions in terms of the Ekeland variational principle and a mathematical exploration of the power law nature of citation distributions. Apart from its inherent value in providing a better understanding of the mathematical underpinnings of bibliometric models, such an approach can be used to derive a citation distribution from first principles.

  2. Approximate design theory for a simple block design with random block effects

    OpenAIRE

    Christof, Karin

    1985-01-01

    Approximate design theory for a simple block design with random block effects / K. Christof ; F. Pukelsheim. - In: Linear statistical inference / ed. by T. Calinski ... - Berlin u. a. : Springer, 1985. - S. 20-28. - (Lecture notes in statistics ; 35)

  3. Predicting community structure in snakes on Eastern Nearctic islands using ecological neutral theory and phylogenetic methods.

    Science.gov (United States)

    Burbrink, Frank T; McKelvy, Alexander D; Pyron, R Alexander; Myers, Edward A

    2015-11-22

    Predicting species presence and richness on islands is important for understanding the origins of communities and how likely it is that species will disperse and resist extinction. The equilibrium theory of island biogeography (ETIB) and, as a simple model of sampling abundances, the unified neutral theory of biodiversity (UNTB), predict that in situations where mainland to island migration is high, species-abundance relationships explain the presence of taxa on islands. Thus, more abundant mainland species should have a higher probability of occurring on adjacent islands. In contrast to UNTB, if certain groups have traits that permit them to disperse to islands better than other taxa, then phylogeny may be more predictive of which taxa will occur on islands. Taking surveys of 54 island snake communities in the Eastern Nearctic along with mainland communities that have abundance data for each species, we use phylogenetic assembly methods and UNTB estimates to predict island communities. Species richness is predicted by island area, whereas turnover from the mainland to island communities is random with respect to phylogeny. Community structure appears to be ecologically neutral and abundance on the mainland is the best predictor of presence on islands. With regard to young and proximate islands, where allopatric or cladogenetic speciation is not a factor, we find that simple neutral models following UNTB and ETIB predict the structure of island communities. © 2015 The Author(s).

  4. Simple perturbative renormalization scheme for supersymmetric gauge theories

    Energy Technology Data Exchange (ETDEWEB)

    Foda, O.E. (Purdue Univ., Lafayette, IN (USA). Dept. of Physics)

    1983-06-30

    We show that the manifestly supersymmetric and gauge-invariant results of Supersymmetric Dimensional renormalization (SDR) are reproduceable through a simple, and mathematically consistent perturbative renormalization technique, where regularization is attained via a map that deforms the momentum space Feynman integrands in a specific way. In particular, it introduces a multiplicative factor of ((p+q)/..delta..)/sup -/delta in each momentum-space loop integral, where p is the magnitude of the loop momentum, q is an arbitrary constant to be chosen as will be explained, thus compensating for loss of translation invariance in p, ..lambda.. is a renormalization mass, and delta is a suitable non-integer: the analog of epsilon in dimensional schemes. All Dirac algebra and integration are four-dimensional, and renormalization is achieved by subtracting poles in delta, followed by setting delta->O. The mathematical inconsistencies of SDR are evaded by construction, since the numbers of fermion and boson degrees of freedom remain unchanged but analytic continuation in the number of dimensions is bypassed. Thus, the technique is equally viable in component and in superfield formalisms, and all anomalies are realized. The origin of the chiral anomaly is that no choice of q satisfies both gauge and chiral Ward identities simultaneously.

  5. A simple perturbative renormalization scheme for supersymmetric gauge theories

    International Nuclear Information System (INIS)

    Foda, O.E.

    1983-01-01

    We show that the manifestly supersymmetric and gauge-invariant results of Supersymmetric Dimensional renormalization (SDR) are reproduceable through a simple, and mathematically consistent perturbative renormalization technique, where regularization is attained via a map that deforms the momentum space Feynman integrands in a specific way. In particular, it introduces a multiplicative factor of [(p+q)/δ] - delta in each momentum-space loop integral, where p is the magnitude of the loop momentum, q is an arbitrary constant to be chosen as will be explained, thus compensating for loss of translation invariance in p, #betta# is a renormalization mass, and delta is a suitable non-integer: the analog of epsilon in dimensional schemes. All Dirac algebra and integration are four-dimensional, and renormalization is achieved by subtracting poles in delta, followed by setting delta->O. The mathematical inconsistencies of SDR are evaded by construction, since the numbers of fermion and boson degrees of freedom remain unchanged but analytic continuation in the number of dimensions is bypassed. Thus, the technique is equally viable in component and in superfield formalisms, and all anomalies are realized. The origin of the chiral anomaly is that no choice of q satisfies both gauge and chiral Ward identities simultaneously. (orig.)

  6. Ecological Systems Theory: Using Spheres of Influence to Support Small-unit Climate and Training

    Science.gov (United States)

    2016-03-01

    identifying the model’s elements and influential individuals, define spheres of influence and construct a model that details the ecological systems...Research Report 1997 Ecological Systems Theory: Using Spheres of Influence to Support Small-unit Climate and Training...Technical review by: Sena Garven, U.S. Army Research Institute Michael D. Wood , Walter Reed Army Institute of Research

  7. Building Theory at the Intersection of Ecological Sustainability and Strategic Management

    DEFF Research Database (Denmark)

    Borland, Helen; Ambrosini, Véronique; Lindgreen, Adam

    2016-01-01

    This article builds theory at the intersection of ecological sustainability and strategic management literature—specifically, in relation to dynamic capabilities literature. By combining industrial organization economics–based, resource-based, and dynamic capability–based views, it is possible...... to develop a better understanding of the strategies that businesses may follow, depending on their managers’ assumptions about ecological sustainability. To develop innovative strategies for ecological sustainability, the dynamic capabilities framework needs to be extended. In particular, the sensing...... sustainability. Finally, this approach offers opportunities for managers and academics to identify, categorize, and exploit business strategies for ecological sustainability....

  8. Toward a social-ecological theory of forest macrosystems for improved ecosystem management

    Science.gov (United States)

    Kleindl, William J.; Stoy, Paul C.; Binford, Michael W.; Desai, Ankur R.; Dietze, Michael C.; Schultz, Courtney A.; Starr, Gregory; Staudhammer, Christina; Wood, David J. A.

    2018-01-01

    The implications of cumulative land-use decisions and shifting climate on forests, require us to integrate our understanding of ecosystems, markets, policy, and resource management into a social-ecological system. Humans play a central role in macrosystem dynamics, which complicates ecological theories that do not explicitly include human interactions. These dynamics also impact ecological services and related markets, which challenges economic theory. Here, we use two forest macroscale management initiatives to develop a theoretical understanding of how management interacts with ecological functions and services at these scales and how the multiple large-scale management goals work either in consort or conflict with other forest functions and services. We suggest that calling upon theories developed for organismal ecology, ecosystem ecology, and ecological economics adds to our understanding of social-ecological macrosystems. To initiate progress, we propose future research questions to add rigor to macrosystem-scale studies: (1) What are the ecosystem functions that operate at macroscales, their necessary structural components, and how do we observe them? (2) How do systems at one scale respond if altered at another scale? (3) How do we both effectively measure these components and interactions, and communicate that information in a meaningful manner for policy and management across different scales?

  9. Information Theory Broadens the Spectrum of Molecular Ecology and Evolution.

    Science.gov (United States)

    Sherwin, W B; Chao, A; Jost, L; Smouse, P E

    2017-12-01

    Information or entropy analysis of diversity is used extensively in community ecology, and has recently been exploited for prediction and analysis in molecular ecology and evolution. Information measures belong to a spectrum (or q profile) of measures whose contrasting properties provide a rich summary of diversity, including allelic richness (q=0), Shannon information (q=1), and heterozygosity (q=2). We present the merits of information measures for describing and forecasting molecular variation within and among groups, comparing forecasts with data, and evaluating underlying processes such as dispersal. Importantly, information measures directly link causal processes and divergence outcomes, have straightforward relationship to allele frequency differences (including monotonicity that q=2 lacks), and show additivity across hierarchical layers such as ecology, behaviour, cellular processes, and nongenetic inheritance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. SOCIO-ECOLOGICAL THEORIES AND EMPIRICAL RESEARCH. COMPARING SOCIAL-ECOLOGICAL SCHOOLS OF THOUGHTS IN ACTION

    OpenAIRE

    Bousquet, F.; Anderies, M.; Antona, M.; Bassett, T.; Benjaminsen, T.; Bonato, O.; Castro, M.; Gautier, D.; Gunderson, L.; Janssen, M.; Kinzig, A.; Lecoq, M.; Lynam, T.; Mathevet, R.; Perrings, C.

    2015-01-01

    Environmental problems, at local scale as well as global scale, are now considered as key issues and scientists are encouraged to be part of the process to address these issues. For the last decades, scholars have been focusing on the study of interactions between social dynamics and ecological processes and produced a set of concepts and scientific discourses aiming at framing the analysis of socio-ecological dynamics and eventually at orienting interventions. Scientific discourses are produ...

  11. A brief introduction to molecular orbital theory of simple polyatomic molecules for undergraduate chemistry students

    Directory of Open Access Journals (Sweden)

    Ione M. Baibich

    2012-01-01

    Full Text Available A simple, four-step method for better introducing undergraduate students to the fundamentals of molecular orbital (MO theory of the polyatomic molecules H2O, NH3, BH3 and SiH4 using group theory is reported. These molecules serve to illustrate the concept of ligand group orbitals (LGOs and subsequent construction of MO energy diagrams on the basis of molecular symmetry requirements.

  12. The Ecology of Interactive Learning Environments: Situating Traditional Theory

    Science.gov (United States)

    Johnson, Genevieve Marie

    2014-01-01

    In educational discourse on human learning (i.e. the result of experience) and development (i.e. the result of maturation), there are three fundamental theoretical frameworks, -- behaviourism, cognitivism and constructivism, each of which have been applied, with varying degrees of success, in online environments. An ecological framework of human…

  13. Mimicking natural ecosystems to develop sustainable supply chains : A theory of socio-ecological intergradation

    NARCIS (Netherlands)

    Gruner, Richard L.; Power, Damien

    2017-01-01

    For most firms, the development of sustainable supply chain practices remains challenging. Using a theory-building approach, we develop a theory of socio-ecological intergradation to provide managers with guidance in mimicking natural ecosystems to develop more local and thus sustainable supply

  14. Linking Simple Economic Theory Models and the Cointegrated Vector AutoRegressive Model

    DEFF Research Database (Denmark)

    Møller, Niels Framroze

    This paper attempts to clarify the connection between simple economic theory models and the approach of the Cointegrated Vector-Auto-Regressive model (CVAR). By considering (stylized) examples of simple static equilibrium models, it is illustrated in detail, how the theoretical model and its stru....... Further fundamental extensions and advances to more sophisticated theory models, such as those related to dynamics and expectations (in the structural relations) are left for future papers......This paper attempts to clarify the connection between simple economic theory models and the approach of the Cointegrated Vector-Auto-Regressive model (CVAR). By considering (stylized) examples of simple static equilibrium models, it is illustrated in detail, how the theoretical model and its......, it is demonstrated how other controversial hypotheses such as Rational Expectations can be formulated directly as restrictions on the CVAR-parameters. A simple example of a "Neoclassical synthetic" AS-AD model is also formulated. Finally, the partial- general equilibrium distinction is related to the CVAR as well...

  15. A simple fish-based approach to assess the ecological quality of freshwater reservoirs in Central Europe

    Directory of Open Access Journals (Sweden)

    Blabolil Petr

    2017-01-01

    Full Text Available The assessment of ecological quality in freshwater ecosystems is a key issue in many countries, but conditions for the development of assessment methodologies are often country-specific. This study proposes a simple methodology for the assessment of the ecological potential of reservoirs based on fish communities using a dataset covering major environmental and pressure gradients in reservoirs in the Czech Republic. Fish data obtained by gillnet sampling were correlated with a proxy of eutrophication as a key indicator of anthropogenic pressure for selecting appropriate fish-based indicators, establishing scoring criteria and developing the index of ecological quality. Expert judgement was also used to select potential fish indicators. Nine indicators were selected for the final fish-based index, fulfilling the criteria required by the Water Framework Directive. Two steps were used to validate the fish-based index quantification of its inter annual stability and sensitivity analysis of individual indicators. Finally, the index was compared to a previously developed general index for Central and Western Europe. Our study demonstrates that a combination of expert judgement and strict validation methods can result in an informative assessment of the ecological conditions, which can help identify conservation and restoration priorities.

  16. A Theory of Transformative Agency in Linked Social-Ecological Systems

    Directory of Open Access Journals (Sweden)

    Frances R. Westley

    2013-09-01

    Full Text Available We reviewed the literature on leadership in linked social-ecological systems and combined it with the literature on institutional entrepreneurship in complex adaptive systems to develop a new theory of transformative agency in linked social-ecological systems. Although there is evidence of the importance of strategic agency in introducing innovation and transforming approaches to management and governance of such systems, there is no coherent theory to explain the wide diversity of strategies identified. Using Holling's adaptive cycle as a model of phases present in innovation and transformation of resilient social-ecological systems, overlaid by Dorado's model of opportunity context (opaque, hazy, transparent in complex adaptive systems, we propose a more coherent theory of strategic agency, which links particular strategies, on the part of transformative agents, to phases of system change.

  17. Simple Theory for the Dynamics of Mean-Field-Like Models of Glass-Forming Fluids

    Science.gov (United States)

    Szamel, Grzegorz

    2017-10-01

    We propose a simple theory for the dynamics of model glass-forming fluids, which should be solvable using a mean-field-like approach. The theory is based on transparent physical assumptions, which can be tested in computer simulations. The theory predicts an ergodicity-breaking transition that is identical to the so-called dynamic transition predicted within the replica approach. Thus, it can provide the missing dynamic component of the random first order transition framework. In the large-dimensional limit the theory reproduces the result of a recent exact calculation of Maimbourg et al. [Phys. Rev. Lett. 116, 015902 (2016), 10.1103/PhysRevLett.116.015902]. Our approach provides an alternative, physically motivated derivation of this result.

  18. A simple extension of contraction theory to study incremental stability properties

    DEFF Research Database (Denmark)

    Jouffroy, Jerome

    Contraction theory is a recent tool enabling to study the stability of nonlinear systems trajectories with respect to one another, and therefore belongs to the class of incremental stability methods. In this paper, we extend the original definition of contraction theory to incorporate...... in an explicit manner the control input of the considered system. Such an extension, called universal contraction, is quite analogous in spirit to the well-known Input-to-State Stability (ISS). It serves as a simple formulation of incremental ISS, external stability, and detectability in a differential setting....... The hierarchical combination result of contraction theory is restated in this framework, and a differential small-gain theorem is derived from results already available in Lyapunov theory....

  19. The force distribution probability function for simple fluids by density functional theory.

    Science.gov (United States)

    Rickayzen, G; Heyes, D M

    2013-02-28

    Classical density functional theory (DFT) is used to derive a formula for the probability density distribution function, P(F), and probability distribution function, W(F), for simple fluids, where F is the net force on a particle. The final formula for P(F) ∝ exp(-AF(2)), where A depends on the fluid density, the temperature, and the Fourier transform of the pair potential. The form of the DFT theory used is only applicable to bounded potential fluids. When combined with the hypernetted chain closure of the Ornstein-Zernike equation, the DFT theory for W(F) agrees with molecular dynamics computer simulations for the Gaussian and bounded soft sphere at high density. The Gaussian form for P(F) is still accurate at lower densities (but not too low density) for the two potentials, but with a smaller value for the constant, A, than that predicted by the DFT theory.

  20. [Connotation characterization and evaluation of ecological well-being based on ecosystem service theory.

    Science.gov (United States)

    Zang, Zheng; Zou, Xin- Qing

    2016-04-22

    China is advocating ecological civilization construction nowadays. Further researches on the relation between ecosystem service and humanity well-being are full of theoretical and practical significance. Combining related researches, this paper defined the concept and connotation of ecological well-being based on ecosystem service theory. Referencing theory of national economic accounting and relative researches, the evaluation indicators of ecological well-being supply and consumption were established. The quantitative characterization and evaluation method of red line of regional ecological well-being was proposed on the basis of location quotient. Then the evaluation of ecological well-being in mainland China in 2012 was set as an example for empirical research. The results showed that the net product values of 6 ecosystems, includingcultivated land, forest land, grassland, wetland, water area and unused land, were respectively 1481.925, 8194.806, 4176.277, 4245.760, 3177.084 and 133.762 billion CNY. Spatial heterogeneity of ecosystem net product in different provinces was distinct. Ecological well-being per capita of forest land, grassland, wetland, cultivated land and unused land in eastern and middle provinces were under the red line and less than the national average. The spatial distribution of 9 kinds of ecological well-being per capita split at Hu's line with high value in northwest and low value in southeast, and was aggravated by differences in density of population and land resources gift.

  1. Using circuit theory to model connectivity in ecology, evolution, and conservation.

    Science.gov (United States)

    McRae, Brad H; Dickson, Brett G; Keitt, Timothy H; Shah, Viral B

    2008-10-01

    Connectivity among populations and habitats is important for a wide range of ecological processes. Understanding, preserving, and restoring connectivity in complex landscapes requires connectivity models and metrics that are reliable, efficient, and process based. We introduce a new class of ecological connectivity models based in electrical circuit theory. Although they have been applied in other disciplines, circuit-theoretic connectivity models are new to ecology. They offer distinct advantages over common analytic connectivity models, including a theoretical basis in random walk theory and an ability to evaluate contributions of multiple dispersal pathways. Resistance, current, and voltage calculated across graphs or raster grids can be related to ecological processes (such as individual movement and gene flow) that occur across large population networks or landscapes. Efficient algorithms can quickly solve networks with millions of nodes, or landscapes with millions of raster cells. Here we review basic circuit theory, discuss relationships between circuit and random walk theories, and describe applications in ecology, evolution, and conservation. We provide examples of how circuit models can be used to predict movement patterns and fates of random walkers in complex landscapes and to identify important habitat patches and movement corridors for conservation planning.

  2. Simple Mindreading Abilities Predict Complex Theory of Mind: Developmental Delay in Autism Spectrum Disorders

    Science.gov (United States)

    Pino, Maria Chiara; Mazza, Monica; Mariano, Melania; Peretti, Sara; Dimitriou, Dagmara; Masedu, Francesco; Valenti, Marco; Franco, Fabia

    2017-01-01

    Theory of mind (ToM) is impaired in individuals with autism spectrum disorders (ASD). The aims of this study were to: (i) examine the developmental trajectories of ToM abilities in two different mentalizing tasks in children with ASD compared to TD children; and (ii) to assess if a ToM simple test known as eyes-test could predict performance on…

  3. Microscopic approach to the theory of light nuclei and to simple nuclear reactions

    International Nuclear Information System (INIS)

    Baz', L.I.; Filippov, G.F.

    1976-01-01

    The results of calculations for the properties of light nuclei and simple nuclear reactions using the Schrodinger multinucleon equation involving the realistic nucleon-nucleon interaction are reviewed. It is noted that the theory for the A(<=)4 nuclei is practically complete at present. The reasons for the good agreement between the theoretical and experimental cross sections of nuclear reactions are given. The programme of a correct separation of the nuclear collective degree of freedom are discussed in detail

  4. A Simple But Effective Canonical Dual Theory Unified Algorithm for Global Optimization

    OpenAIRE

    Zhang, Jiapu

    2011-01-01

    Numerical global optimization methods are often very time consuming and could not be applied for high-dimensional nonconvex/nonsmooth optimization problems. Due to the nonconvexity/nonsmoothness, directly solving the primal problems sometimes is very difficult. This paper presents a very simple but very effective canonical duality theory (CDT) unified global optimization algorithm. This algorithm has convergence is proved in this paper. More important, for this CDT-unified algorithm, numerous...

  5. Exact solubility of Chern-Simons theory with compact simple gauge group

    International Nuclear Information System (INIS)

    Hayashi, Masahito

    1993-01-01

    We show that vacuum expectation values of Wilson loop operators in (2+1)-dimensional Chern-Simons theory satisfy algebraic equations. Interestingly enough, vacuum expectation values for unknotted Wilson loop operators in any representation of any compact and simple group are exactly computed by solving the equations. So-called 'skein relations', which give us algebraic equations among vacuum expectation values of different Wilson loop operators, are constructed. In our formalism, quantum group symmetry appears naturally. (orig.)

  6. Simple compactifications and black p-branes in Gauss-Bonnet and Lovelock theories

    International Nuclear Information System (INIS)

    Giribet, Gaston; Oliva, Julio; Troncoso, Ricardo

    2006-01-01

    We look for the existence of asymptotically flat simple compactifications of the form M D-p x T p in D-dimensional gravity theories with higher powers of the curvature. Assuming the manifold M D-p to be spherically symmetric, it is shown that the Einstein-Gauss-Bonnet theory admits this class of solutions only for the pure Einstein-Hilbert or Gauss-Bonnet Lagrangians, but not for an arbitrary linear combination of them. Once these special cases have been selected, the requirement of spherical symmetry is no longer relevant since actually any solution of the pure Einstein or pure Gauss-Bonnet theories can then be toroidally extended to higher dimensions. Depending on p and the spacetime dimension, the metric on M D-p may describe a black hole or a spacetime with a conical singularity, so that the whole spacetime describes a black or a cosmic p-brane, respectively. For the purely Gauss-Bonnet theory it is shown that, if M D-p is four-dimensional, a new exotic class of black hole solutions exists, for which spherical symmetry can be relaxed. Under the same assumptions, it is also shown that simple compactifications acquire a similar structure for a wide class of theories among the Lovelock family which accepts this toroidal extension. The thermodynamics of black p-branes is also discussed, and it is shown that a thermodynamical analogue of the Gregory-Laflamme transition always occurs regardless the spacetime dimension or the theory considered, hence not only for General Relativity. Relaxing the asymptotically flat behavior, it is also shown that exact black brane solutions exist within a very special class of Lovelock theories

  7. Sampling in ecology and evolution - bridging the gap between theory and practice

    Science.gov (United States)

    Albert, C.H.; Yoccoz, N.G.; Edwards, T.C.; Graham, C.H.; Zimmermann, N.E.; Thuiller, W.

    2010-01-01

    Sampling is a key issue for answering most ecological and evolutionary questions. The importance of developing a rigorous sampling design tailored to specific questions has already been discussed in the ecological and sampling literature and has provided useful tools and recommendations to sample and analyse ecological data. However, sampling issues are often difficult to overcome in ecological studies due to apparent inconsistencies between theory and practice, often leading to the implementation of simplified sampling designs that suffer from unknown biases. Moreover, we believe that classical sampling principles which are based on estimation of means and variances are insufficient to fully address many ecological questions that rely on estimating relationships between a response and a set of predictor variables over time and space. Our objective is thus to highlight the importance of selecting an appropriate sampling space and an appropriate sampling design. We also emphasize the importance of using prior knowledge of the study system to estimate models or complex parameters and thus better understand ecological patterns and processes generating these patterns. Using a semi-virtual simulation study as an illustration we reveal how the selection of the space (e.g. geographic, climatic), in which the sampling is designed, influences the patterns that can be ultimately detected. We also demonstrate the inefficiency of common sampling designs to reveal response curves between ecological variables and climatic gradients. Further, we show that response-surface methodology, which has rarely been used in ecology, is much more efficient than more traditional methods. Finally, we discuss the use of prior knowledge, simulation studies and model-based designs in defining appropriate sampling designs. We conclude by a call for development of methods to unbiasedly estimate nonlinear ecologically relevant parameters, in order to make inferences while fulfilling requirements of

  8. Bridging food webs, ecosystem metabolism, and biogeochemistry using ecological stoichiometry theory

    DEFF Research Database (Denmark)

    Welti, Nina; Striebel, Maren; Ulseth, Amber J.

    2017-01-01

    process rates). ES theory holds the promise to be a unifying concept to link across hierarchical scales of patterns and processes in ecology, but this has not been fully achieved. Therefore, we propose connecting the expertise of aquatic ecologists and biogeochemists with ES theory as a common currency......, we propose that using ES to link nutrient cycling, trophic dynamics, and ecosystem metabolism would allow for a more holistic understanding of ecosystem functions in a changing environment....

  9. A Philosophical Analysis of David Orr's Theory of Ecological Literacy: Biophilia, Ecojustice and Moral Education in School Learning Communities

    Science.gov (United States)

    Mitchell, Debra B.; Mueller, Michael P.

    2011-01-01

    In his writings, David Orr claims that the US is in an "ecological crisis" and that this stems from a crisis of education. He outlines a theory of ecological literacy, a mode by which we better learn the ecology of the Earth and live in a sustainable manner. While emphasizing a shock doctrine, the diagnosis of "crisis" may be…

  10. Building Theory at the Intersection of Ecological Sustainability and Strategic Management

    DEFF Research Database (Denmark)

    Borland, Helen; Ambrosini, Véronique; Lindgreen, Adam

    2016-01-01

    This article builds theory at the intersection of ecological sustainability and strategic management literature—specifically, in relation to dynamic capabilities literature. By combining industrial organization economics–based, resource-based, and dynamic capability–based views, it is possible...... to develop a better understanding of the strategies that businesses may follow, depending on their managers’ assumptions about ecological sustainability. To develop innovative strategies for ecological sustainability, the dynamic capabilities framework needs to be extended. In particular, the sensing......–seizing–maintaining competitiveness framework should operate not only within the boundaries of a business ecosystem but in relation to global biophysical ecosystems; in addition, two more dynamic capabilities should be added, namely, remapping and reaping. This framework can explicate core managerial beliefs about ecological...

  11. The social ecology of resilience: a handbook of theory and practice

    National Research Council Canada - National Science Library

    Ungar, Michael

    2012-01-01

    ..., who helped with many of the logistical supports that made this book possible, and Dorothy Bottrell for her helpful review of my own contributions. Finally, a sincere thank you to my support team at Springer. v ContentsContents 1 Introduction to the Volume ... Michael Ungar 1 Part I Introduction to the Theory 2 3 4 5 Social Ecologies and Their Contribu...

  12. Simple Rules for an Efficient Use of Geographic Information Systems in Molecular Ecology

    Directory of Open Access Journals (Sweden)

    Kevin Leempoel

    2017-04-01

    Full Text Available Geographic Information Systems (GIS are becoming increasingly popular in the context of molecular ecology and conservation biology thanks to their display options efficiency, flexibility and management of geodata. Indeed, spatial data for wildlife and livestock species is becoming a trend with many researchers publishing genomic data that is specifically suitable for landscape studies. GIS uniquely reveal the possibility to overlay genetic information with environmental data and, as such, allow us to locate and analyze genetic boundaries of various plant and animal species or to study gene-environment associations (GEA. This means that, using GIS, we can potentially identify the genetic bases of species adaptation to particular geographic conditions or to climate change. However, many biologists are not familiar with the use of GIS and underlying concepts and thus experience difficulties in finding relevant information and instructions on how to use them. In this paper, we illustrate the power of free and open source GIS approaches and provide essential information for their successful application in molecular ecology. First, we introduce key concepts related to GIS that are too often overlooked in the literature, for example coordinate systems, GPS accuracy and scale. We then provide an overview of the most employed open-source GIS-related software, file formats and refer to major environmental databases. We also reconsider sampling strategies as high costs of Next Generation Sequencing (NGS data currently diminish the number of samples that can be sequenced per location. Thereafter, we detail methods of data exploration and spatial statistics suited for the analysis of large genetic datasets. Finally, we provide suggestions to properly edit maps and to make them as comprehensive as possible, either manually or trough programming languages.

  13. The use of ecological momentary assessment to test appraisal theories of emotion.

    Science.gov (United States)

    Tong, Eddie M W; Bishop, George D; Enkelmann, Hwee Chong; Why, Yong Peng; Diong, Siew Maan; Khader, Majeed; Ang, Jansen

    2005-12-01

    Although appraisal theories have received strong empirical support, there are methodological concerns about the research, including biased recall, heuristic responding, ethical issues, and weak and unrealistic induction of emotions in laboratories. To provide a more ecologically valid test of appraisal theories, the authors used ecological momentary assessment, in which the emotions and appraisals of Singaporean police officers were measured online over the course of an ordinary workday. The research focused on happiness. Support was obtained for predictions, demonstrating the generalizability of appraisal theories to a nonlaboratory setting and circumventing the shortcomings of previously used methodologies. Also, evidence was obtained that happiness was reported primarily in association with a specific combination of 3 relevant appraisals: high pleasantness, high perceived control, and low moral violation. Copyright (c) 2005 APA, all rights reserved.

  14. Theories of practice - new inspiration for ecological economic studies on consumption

    DEFF Research Database (Denmark)

    Røpke, Inge

    2009-01-01

    The dynamics behind ever-increasing consumption have long been a core issue of ecological economics. Studies on this topic have traditionally drawn not only on insights from economics, but also from such disciplines as sociology, anthropology and psychology. In recent years, a practice theory...... approach has emerged in sociological consumption studies, as part of a general wave of renewed interest in practice theory emanating from a desire to move beyond such dominant dualisms as the structure-actor opposition in sociology. The purpose of this paper is to introduce the practice theory approach...... in relation to studies of everyday life, domestic practices and consumption, and to argue that this approach can be fruitful for ecological economics and other fields interested in the environmental aspects of consumption. The paper emphasizes the immense challenge involved in promoting sustainable...

  15. The ecology of cancer from an evolutionary game theory perspective.

    Science.gov (United States)

    Pacheco, Jorge M; Santos, Francisco C; Dingli, David

    2014-08-06

    The accumulation of somatic mutations, to which the cellular genome is permanently exposed, often leads to cancer. Analysis of any tumour shows that, besides the malignant cells, one finds other 'supporting' cells such as fibroblasts, immune cells of various types and even blood vessels. Together, these cells generate the microenvironment that enables the malignant cell population to grow and ultimately lead to disease. Therefore, understanding the dynamics of tumour growth and response to therapy is incomplete unless the interactions between the malignant cells and normal cells are investigated in the environment in which they take place. The complex interactions between cells in such an ecosystem result from the exchange of information in the form of cytokines- and adhesion-dependent interactions. Such processes impose costs and benefits to the participating cells that may be conveniently recast in the form of a game pay-off matrix. As a result, tumour progression and dynamics can be described in terms of evolutionary game theory (EGT), which provides a convenient framework in which to capture the frequency-dependent nature of ecosystem dynamics. Here, we provide a tutorial review of the central aspects of EGT, establishing a relation with the problem of cancer. Along the way, we also digress on fitness and of ways to compute it. Subsequently, we show how EGT can be applied to the study of the various manifestations and dynamics of multiple myeloma bone disease and its preceding condition known as monoclonal gammopathy of undetermined significance. We translate the complex biochemical signals into costs and benefits of different cell types, thus defining a game pay-off matrix. Then we use the well-known properties of the EGT equations to reduce the number of core parameters that characterize disease evolution. Finally, we provide an interpretation of these core parameters in terms of what their function is in the ecosystem we are describing and generate

  16. Ecology

    Science.gov (United States)

    Ternjej, Ivancica; Mihaljevic, Zlatko

    2017-10-01

    Ecology is a science that studies the mutual interactions between organisms and their environment. The fundamental subject of interest in ecology is the individual. Topics of interest to ecologists include the diversity, distribution and number of particular organisms, as well as cooperation and competition between organisms, both within and among ecosystems. Today, ecology is a multidisciplinary science. This is particularly true when the subject of interest is the ecosystem or biosphere, which requires the knowledge and input of biologists, chemists, physicists, geologists, geographists, climatologists, hydrologists and many other experts. Ecology is applied in a science of restoration, repairing disturbed sites through human intervention, in natural resource management, and in environmental impact assessments.

  17. Thermophysical properties of simple liquid metals: A brief review of theory

    Science.gov (United States)

    Stroud, David

    1993-01-01

    In this paper, we review the current theory of the thermophysical properties of simple liquid metals. The emphasis is on thermodynamic properties, but we also briefly discuss the nonequilibrium properties of liquid metals. We begin by defining a 'simple liquid metal' as one in which the valence electrons interact only weakly with the ionic cores, so that the interaction can be treated by perturbation theory. We then write down the equilibrium Hamiltonian of a liquid metal as a sum of five terms: the bare ion-ion interaction, the electron-electron interaction, the bare electron-ion interaction, and the kinetic energies of electrons and ions. Since the electron-ion interaction can be treated by perturbation, the electronic part contributes in two ways to the Helmholtz free energy: it gives a density-dependent term which is independent of the arrangement of ions, and it acts to screen the ion-ion interaction, giving rise to effective ion-ion pair potentials which are density-dependent, in general. After sketching the form of a typical pair potential, we briefly enumerate some methods for calculating the ionic distribution function and hence the Helmholtz free energy of the liquid: monte Carlo simulations, molecular dynamics simulations, and thermodynamic perturbation theory. The final result is a general expression for the Helmholtz free energy of the liquid metal. It can be used to calculate a wide range of thermodynamic properties of simple metal liquids, which we enumerate. They include not only a range of thermodynamic coefficients of both metals and alloys, but also many aspects of the phase diagram, including freezing curves of pure elements and phase diagrams of liquid alloys (including liquidus and solidus curves). We briefly mention some key discoveries resulting from previous applications of this method, and point out that the same methods work for other materials not normally considered to be liquid metals (such as colloidal suspensions, in which the

  18. Transport in simple liquids and dense gases: kinetic mean-field theory and the KAC limit

    International Nuclear Information System (INIS)

    Karkheck, J.; Stell, G.; Martina, E.

    1982-01-01

    Maximization of entropy is used in conjunction with the BBGKY hierarchy to obtain a closed one-particle kinetic equation. For an interparticle potential of hard-sphere core plus smooth attractive tail, this equation contains a hard-core collision integral, identical to that of the revised Enskog theory, plus a mean-field term which is linear in the tail strength. The thermodynamics contained therein leads directly to the now-standard statistical-mechanical methods to construct a state-dependent effective hard-core potential in relation to a more realistic potential. These methods induce an extension of the transport coefficients to the Lennard-Jones potential. Predictions of the resulting transport theory compare very favorably with thermal conductivity and shear viscosity experimental results for real simple liquids and dense gases, and also with molecular dynamics simulation results. Poor agreement between theory and experiment is found for moderately dense and dilute gases. The kinetic theory also contains an entropy functional and an H-theorem is proven. Extension to mixtures is straightforward and the Kac-limit is discussed in detail

  19. A simple derivation of the exact quasiparticle theory and its extension to arbitrary initial excited eigenstates.

    Science.gov (United States)

    Ohno, Kaoru; Ono, Shota; Isobe, Tomoharu

    2017-02-28

    The quasiparticle (QP) energies, which are minus of the energies required by removing or produced by adding one electron from/to the system, corresponding to the photoemission or inverse photoemission (PE/IPE) spectra, are determined together with the QP wave functions, which are not orthonormal and even not linearly independent but somewhat similar to the normal spin orbitals in the theory of the configuration interaction, by self-consistently solving the QP equation coupled with the equation for the self-energy. The electron density, kinetic, and all interaction energies can be calculated using the QP wave functions. We prove in a simple way that the PE/IPE spectroscopy and therefore this QP theory can be applied to an arbitrary initial excited eigenstate. In this proof, we show that the energy-dependence of the self-energy is not an essential difficulty, and the QP picture holds exactly if there is no relaxation mechanism in the system. The validity of the present theory for some initial excited eigenstates is tested using the one-shot GW approximation for several atoms and molecules.

  20. Doubly self-consistent field theory of grafted polymers under simple shear in steady state

    International Nuclear Information System (INIS)

    Suo, Tongchuan; Whitmore, Mark D.

    2014-01-01

    We present a generalization of the numerical self-consistent mean-field theory of polymers to the case of grafted polymers under simple shear. The general theoretical framework is presented, and then applied to three different chain models: rods, Gaussian chains, and finitely extensible nonlinear elastic (FENE) chains. The approach is self-consistent at two levels. First, for any flow field, the polymer density profile and effective potential are calculated self-consistently in a manner similar to the usual self-consistent field theory of polymers, except that the calculation is inherently two-dimensional even for a laterally homogeneous system. Second, through the use of a modified Brinkman equation, the flow field and the polymer profile are made self-consistent with respect to each other. For all chain models, we find that reasonable levels of shear cause the chains to tilt, but it has very little effect on the overall thickness of the polymer layer, causing a small decrease for rods, and an increase of no more than a few percent for the Gaussian and FENE chains. Using the FENE model, we also probe the individual bond lengths, bond correlations, and bond angles along the chains, the effects of the shear on them, and the solvent and bonded stress profiles. We find that the approximations needed within the theory for the Brinkman equation affect the bonded stress, but none of the other quantities

  1. Toward a Theory of Integrated Urban Ecology: Complementing Pickett et al.

    Directory of Open Access Journals (Sweden)

    Robert Mugerauer

    2010-12-01

    Full Text Available The analyses substantially delineating "integrative studies of large urban areas as bio-physical-social complexes" and the suggestions by Pickett et al. in "Beyond Urban Legends" (Bioscience 2008 58 139-150 provide an initial framework for a theory of urban ecology. This article intends to contribute to the project by: 1 improving the philosophical rigor of critical concepts and epistemologies; 2 making explicit the complementary theoretical and empirical work in urban ecology already being done that can be better integrated, for example, studies from outside the U.S. and uses of actor network theory; 3 bringing forward more disciplines and theories which successfully deploy modes of thinking, research procedures, and practices more adequate to the phenomena at all scales and levels of particularity, i.e., micro, phenomenal, macro, to fill in some of the empirical gaps in the middle, specifically those having to do with human values and the richness of the everyday lifeworld. In addition to what is available within complexity theory itself, chief among the approaches to be utilized are phenomenology, ethnographic thick description, and actor network theory.

  2. Simple Mindreading Abilities Predict Complex Theory of Mind: Developmental Delay in Autism Spectrum Disorders.

    Science.gov (United States)

    Pino, Maria Chiara; Mazza, Monica; Mariano, Melania; Peretti, Sara; Dimitriou, Dagmara; Masedu, Francesco; Valenti, Marco; Franco, Fabia

    2017-09-01

    Theory of mind (ToM) is impaired in individuals with autism spectrum disorders (ASD). The aims of this study were to: (i) examine the developmental trajectories of ToM abilities in two different mentalizing tasks in children with ASD compared to TD children; and (ii) to assess if a ToM simple test known as eyes-test could predict performance on the more advanced ToM task, i.e. comic strip test. Based on a sample of 37 children with ASD and 55 TD children, our results revealed slower development at varying rates in all ToM measures in children with ASD, with delayed onset compared to TD children. These results could stimulate new treatments for social abilities, which would lessen the social deficit in ASD.

  3. Simple theory of how spiral galaxies acquire their principal global properties

    International Nuclear Information System (INIS)

    Burstein, D.; Sarazin, C.L.

    1983-01-01

    The strongest correlations among the global properties of spiral galaxies are the power law correlations between luminosity and rotation velocity (the Tully-Fisher relation) and between luminosity and luminous radius. Both of these relations are derived from a single density-radius power-law relation for spiral galaxies, assuming that the total mass-to-luminosity ratio is fixed by the Hubble type of the spiral, and that spirals gain their angular momentum through tidal interactions. The predictions of this simple theory are consistent with the observed luminosity and mass properties of the Hubble type-restricted samples of spiral galaxies studied by Rubin et al. This model suggests that many of the physical properties of spiral galaxies, and of the Hubble sequence, originate before or during the formation of galaxies

  4. Simple theory of the inverse Faraday effect with relationship to optical constants N and K

    International Nuclear Information System (INIS)

    Yoshino, Toshihiko

    2011-01-01

    The inverse Faraday effect in general materials is theoretically investigated based on the classical motion of an electron. It is shown that the inverse Faraday effect is simply and explicitly expressed in terms of optical constants N and K, i.e., the real and imaginary parts of complex refractive index of materials. The derived new formula provides a good physical perspective for the inverse Faraday effect and enables its easy quantitative evaluation from familiar optical constants. - Highlights: → The theory of the inverse Faraday effect in general materials is presented based on the classical motion model of electron. → The simple relationship between optical constants of materials and the inverse Faraday effect is given. → The given new formula enables easy quantitative evaluation of the inverse Faraday effect from known optical constants.

  5. Non-perturbative analysis of some simple field theories on a momentum space lattice

    International Nuclear Information System (INIS)

    Brooks, E.D. III.

    1984-01-01

    In this work, a new technique is developed for the numerical study of quantum field theory. The procedure, borrowed from nonrelativistic quantum mechanics, is that of finding the eigenvalues of a finite Hamiltonian matrix. The matrix is created by evaluating the matrix elements of the Hamiltonian operator on a finite basis of states. The eigenvalues and eigenvectors of the finite dimensional matrix become an accurate approximation to those of the physical system as the finite basis of states is extended to become more complete. A model of scalars coupled to fermions in 0 + 1 dimensions as a simple field theory is studied to consider in the course of developing the technique. Having developed the numerical and analytical techniques, a Fermi field coupled to a Bose field in 1 + 1 dimensions with the Yukawa coupling lambda anti-psi phi psi is considered. The large coupling limit basis of the 0 + 1 dimensional model is extended to this case using a Bogoliubov transformation on the fermions. It provides a handle on the behavior of the system in the large coupling limit. The effects of renormalization and the generation of bound states are considered

  6. Linking niche theory to ecological impacts of successful invaders: insights from resource fluctuation-specialist herbivore interactions.

    Science.gov (United States)

    Gidoin, Cindy; Roques, Lionel; Boivin, Thomas

    2015-03-01

    Theories of species coexistence and invasion ecology are fundamentally connected and provide a common theoretical framework for studying the mechanisms underlying successful invasions and their ecological impacts. Temporal fluctuations in resource availability and differences in life-history traits between invasive and resident species are considered as likely drivers of the dynamics of invaded communities. Current critical issues in invasion ecology thus relate to the extent to which such mechanisms influence coexistence between invasive and resident species and to the ability of resident species to persist in an invasive-dominated ecosystem. We tested how a fluctuating resource, and species trait differences may explain and help predict long-term impacts of biological invasions in forest specialist insect communities. We used a simple invasion system comprising closely related invasive and resident seed-specialized wasps (Hymenoptera: Torymidae) competing for a well-known fluctuating resource and displaying divergent diapause, reproductive and phenological traits. Based on extensive long-term field observations (1977-2010), we developed a combination of mechanistic and statistical models aiming to (i) obtain a realistic description of the population dynamics of these interacting species over time, and (ii) clarify the respective contributions of fluctuation-dependent and fluctuation-independent mechanisms to long-term impact of invasion on the population dynamics of the resident wasp species. We showed that a fluctuation-dependent mechanism was unable to promote coexistence of the resident and invasive species. Earlier phenology of the invasive species was the main driver of invasion success, enabling the invader to exploit an empty niche. Phenology also had the greatest power to explain the long-term negative impact of the invasive on the resident species, through resource pre-emption. This study provides strong support for the critical role of species

  7. Species traits and environmental constraints: entomological research and the history of ecological theory.

    Science.gov (United States)

    Statzner, B; Hildrew, A G; Resh, V H

    2001-01-01

    The role that entomology has played in the historical (1800s-1970s) development of ecological theories that match species traits with environmental constraints is reviewed along three lineages originating from the ideas of a minister (Malthus TR. 1798. An Essay on the Principle of Population. London: Johnson) and a chemist (Liebig J. 1840. Die Organische Chemie in ihrer Anwendung auf Agricultur und Physiologie. Braunschweig: Vieweg). Major developments in lineage 1 focus on habitat as a filter for species traits, succession, nonequilibrium and equilibrium conditions, and generalizations about the correlation of traits to environmental constraints. In lineage 2, we trace the evolution of the niche concept and focus on ecophysiological traits, biotic interactions, and environmental conditions. Finally, we describe the conceptual route from early demographic studies of human and animal populations to the r-K concept in lineage 3. In the 1970s, the entomologist Southwood merged these three lineages into the "habitat templet concept" (Southwood TRE. 1977. J. Anim. Ecol. 46:337-65), which has stimulated much subsequent research in entomology and general ecology. We conclude that insects have been a far more important resource for the development of ecological theory than previously acknowledged.

  8. Applying ecological models to communities of genetic elements: the case of neutral theory.

    Science.gov (United States)

    Linquist, Stefan; Cottenie, Karl; Elliott, Tyler A; Saylor, Brent; Kremer, Stefan C; Gregory, T Ryan

    2015-07-01

    A promising recent development in molecular biology involves viewing the genome as a mini-ecosystem, where genetic elements are compared to organisms and the surrounding cellular and genomic structures are regarded as the local environment. Here, we critically evaluate the prospects of ecological neutral theory (ENT), a popular model in ecology, as it applies at the genomic level. This assessment requires an overview of the controversy surrounding neutral models in community ecology. In particular, we discuss the limitations of using ENT both as an explanation of community dynamics and as a null hypothesis. We then analyse a case study in which ENT has been applied to genomic data. Our central finding is that genetic elements do not conform to the requirements of ENT once its assumptions and limitations are made explicit. We further compare this genome-level application of ENT to two other, more familiar approaches in genomics that rely on neutral mechanisms: Kimura's molecular neutral theory and Lynch's mutational-hazard model. Interestingly, this comparison reveals that there are two distinct concepts of neutrality associated with these models, which we dub 'fitness neutrality' and 'competitive neutrality'. This distinction helps to clarify the various roles for neutral models in genomics, for example in explaining the evolution of genome size. © 2015 John Wiley & Sons Ltd.

  9. Neural coding of basic reward terms of animal learning theory, game theory, microeconomics and behavioural ecology.

    Science.gov (United States)

    Schultz, Wolfram

    2004-04-01

    Neurons in a small number of brain structures detect rewards and reward-predicting stimuli and are active during the expectation of predictable food and liquid rewards. These neurons code the reward information according to basic terms of various behavioural theories that seek to explain reward-directed learning, approach behaviour and decision-making. The involved brain structures include groups of dopamine neurons, the striatum including the nucleus accumbens, the orbitofrontal cortex and the amygdala. The reward information is fed to brain structures involved in decision-making and organisation of behaviour, such as the dorsolateral prefrontal cortex and possibly the parietal cortex. The neural coding of basic reward terms derived from formal theories puts the neurophysiological investigation of reward mechanisms on firm conceptual grounds and provides neural correlates for the function of rewards in learning, approach behaviour and decision-making.

  10. [Nursing care of a school-age child with asthma: an ecological system theory approach].

    Science.gov (United States)

    Tzeng, Yu-Fen; Gau, Bih-Shya

    2012-02-01

    This research applied the Ecological System Theory of Dr. Bronfenbrenner (1979) to evaluate and analyze the impact of a school-age asthmatic child's ecological environment on the child's development. This project ran from March 16th to April 16th, 2010. A full range of data was collected during clinical care, outpatient follow-up services, telephone interviews, home visits, and school visits and then identified and analyzed. Results indicated that the family, household environment, campus, teachers, classmates, physical education program, and medical staffs comprised the most immediate microsystem and that parents, school nurses, teachers, and classmates formed the child's mesosystem. Researchers found a lack of understanding and appreciation in the mesosystem regarding asthmatic patient care needs. Hidden factors in the environment induced asthma, which eventually caused the child to be unable to obtain necessary medical care assistance. The exosystem reflected adequacy of the family social economy. The father's flexible working hours allowed him to allocate more time to childcare responsibilities. The government Asthma Medical Payment program also facilitated effective care. The macrosystem demonstrated parental cognition related to asthma treatment and caring to be deeply influenced by local customs. Thus, rather than using advanced medical treatments, parents preferred to follow traditional Chinese medicinal practices. Evaluation using the Ecological of Human Development Theory showed the subject's ecology environment relationships as based upon a foundation of family and school. Therefore, active family and school support for an asthma management plan appropriate to the subject's needs was critical. Asthma symptoms were better controlled after the child and his parents invested greater effort in mastering asthma management protocols.

  11. Extended SL(2,R)/U(1) characters, or modular properties of a simple non-rational conformal field theory

    International Nuclear Information System (INIS)

    Israel, D.; Pakman, A.; Troost, J.

    2004-01-01

    We define extended SL(2,R)/U(1) characters which include a sum over winding sectors. By embedding these characters into similarly extended characters of N=2 algebras, we show that they have nice modular transformation properties. We calculate the modular matrices of this simple but non-trivial non-rational conformal field theory explicitly. As a result, we show that discrete SL(2,R) representations mix with continuous SL(2,R) representations under modular transformations in the coset conformal field theory. We comment upon the significance of our results for a general theory of non-rational conformal field theories. (author)

  12. The Construction of Higher Education Entrepreneur Services Network System a Research Based on Ecological Systems Theory

    Science.gov (United States)

    Xue, Jingxin

    The article aims to completely, systematically and objectively analyze the current situation of Entrepreneurship Education in China with Ecological Systems Theory. From this perspective, the author discusses the structure, function and its basic features of higher education entrepreneur services network system, and puts forward the opinion that every entrepreneurship organization in higher education institution does not limited to only one platform. Different functional supporting platforms should be combined closed through composite functional organization to form an integrated network system, in which each unit would impels others' development.

  13. Educating toward Direct Democracy and Ecological Sustainability: Theory of Social Ecology as a Framework for Critical, Democratic, and Community-Based Education

    Science.gov (United States)

    Holohan, Kevin J.

    2012-01-01

    The aim of this dissertation project was to explore and extrapolate the work of the left-libertarian social theorist, Murray Bookchin (1921-2006), paying particular attention to his theory of social ecology and to examine its implications for and use as a comprehensive philosophical/theoretical framework for alternative secondary education that…

  14. Right to Place: A Political Theory of Animal Rights in Harmony with Environmental and Ecological Principles

    Directory of Open Access Journals (Sweden)

    Eleni Panagiotarakou

    2014-09-01

    Full Text Available The focus of this paper is on the “right to place” as a political theory of wild animal rights. Out of the debate between terrestrial cosmopolitans inspired by Kant and Arendt and rooted cosmopolitan animal right theorists, the right to place emerges from the fold of rooted cosmopolitanism in tandem with environmental and ecological principles. Contrary to terrestrial cosmopolitans—who favour extending citizenship rights to wild animals and advocate at the same time large-scale humanitarian interventions and unrestricted geographical mobility—I argue that the well-being of wild animals is best served by the right to place theory on account of its sovereignty model. The right to place theory advocates human non-interference in wildlife communities, opposing even humanitarian interventions, which carry the risk of unintended consequences. The right to place theory, with its emphasis on territorial sovereignty, bases its opposition to unrestricted geographical mobility on two considerations: (a the non-generalist nature of many species and (b the potential for abuse via human encroachment. In a broader context, the advantage of the right to place theory lies in its implicit environmental demands: human population control and sustainable lifestyles.

  15. Microbiomes: unifying animal and plant systems through the lens of community ecology theory.

    Science.gov (United States)

    Christian, Natalie; Whitaker, Briana K; Clay, Keith

    2015-01-01

    The field of microbiome research is arguably one of the fastest growing in biology. Bacteria feature prominently in studies on animal health, but fungi appear to be the more prominent functional symbionts for plants. Despite the similarities in the ecological organization and evolutionary importance of animal-bacterial and plant-fungal microbiomes, there is a general failure across disciplines to integrate the advances made in each system. Researchers studying bacterial symbionts in animals benefit from greater access to efficient sequencing pipelines and taxonomic reference databases, perhaps due to high medical and veterinary interest. However, researchers studying plant-fungal symbionts benefit from the relative tractability of fungi under laboratory conditions and ease of cultivation. Thus each system has strengths to offer, but both suffer from the lack of a common conceptual framework. We argue that community ecology best illuminates complex species interactions across space and time. In this synthesis we compare and contrast the animal-bacterial and plant-fungal microbiomes using six core theories in community ecology (i.e., succession, community assembly, metacommunities, multi-trophic interactions, disturbance, restoration). The examples and questions raised are meant to spark discussion amongst biologists and lead to the integration of these two systems, as well as more informative, manipulatory experiments on microbiomes research.

  16. Microbiomes: unifying animal and plant systems through the lens of community ecology theory

    Directory of Open Access Journals (Sweden)

    Natalie eChristian

    2015-09-01

    Full Text Available The field of microbiome research is arguably one of the fastest growing in biology. Bacteria feature prominently in studies on animal health, but fungi appear to be the more prominent functional symbionts for plants. Despite the similarities in the ecological organization and evolutionary importance of animal-bacterial and plant-fungal microbiomes, there is a general failure across disciplines to integrate the advances made in each system. Researchers studying bacterial symbionts in animals benefit from greater access to efficient sequencing pipelines and taxonomic reference databases, perhaps due to high medical and veterinary interest. However, researchers studying plant-fungal symbionts benefit from the relative tractability of fungi under laboratory conditions and ease of cultivation. Thus each system has strengths to offer, but both suffer from the lack of a common conceptual framework. We argue that community ecology best illuminates complex species interactions across space and time. In this synthesis we compare and contrast the animal-bacterial and plant-fungal microbiomes using six core theories in community ecology (i.e., succession, community assembly, metacommunities, multi-trophic interactions, disturbance, restoration. The examples and questions raised are meant to spark discussion amongst biologists and lead to the integration of these two systems, as well as more informative, manipulatory experiments on microbiomes research.

  17. Microbiomes: unifying animal and plant systems through the lens of community ecology theory

    Science.gov (United States)

    Christian, Natalie; Whitaker, Briana K.; Clay, Keith

    2015-01-01

    The field of microbiome research is arguably one of the fastest growing in biology. Bacteria feature prominently in studies on animal health, but fungi appear to be the more prominent functional symbionts for plants. Despite the similarities in the ecological organization and evolutionary importance of animal-bacterial and plant–fungal microbiomes, there is a general failure across disciplines to integrate the advances made in each system. Researchers studying bacterial symbionts in animals benefit from greater access to efficient sequencing pipelines and taxonomic reference databases, perhaps due to high medical and veterinary interest. However, researchers studying plant–fungal symbionts benefit from the relative tractability of fungi under laboratory conditions and ease of cultivation. Thus each system has strengths to offer, but both suffer from the lack of a common conceptual framework. We argue that community ecology best illuminates complex species interactions across space and time. In this synthesis we compare and contrast the animal-bacterial and plant–fungal microbiomes using six core theories in community ecology (i.e., succession, community assembly, metacommunities, multi-trophic interactions, disturbance, restoration). The examples and questions raised are meant to spark discussion amongst biologists and lead to the integration of these two systems, as well as more informative, manipulatory experiments on microbiomes research. PMID:26441846

  18. Gas production in the Barnett Shale obeys a simple scaling theory.

    Science.gov (United States)

    Patzek, Tad W; Male, Frank; Marder, Michael

    2013-12-03

    Natural gas from tight shale formations will provide the United States with a major source of energy over the next several decades. Estimates of gas production from these formations have mainly relied on formulas designed for wells with a different geometry. We consider the simplest model of gas production consistent with the basic physics and geometry of the extraction process. In principle, solutions of the model depend upon many parameters, but in practice and within a given gas field, all but two can be fixed at typical values, leading to a nonlinear diffusion problem we solve exactly with a scaling curve. The scaling curve production rate declines as 1 over the square root of time early on, and it later declines exponentially. This simple model provides a surprisingly accurate description of gas extraction from 8,294 wells in the United States' oldest shale play, the Barnett Shale. There is good agreement with the scaling theory for 2,057 horizontal wells in which production started to decline exponentially in less than 10 y. The remaining 6,237 horizontal wells in our analysis are too young for us to predict when exponential decline will set in, but the model can nevertheless be used to establish lower and upper bounds on well lifetime. Finally, we obtain upper and lower bounds on the gas that will be produced by the wells in our sample, individually and in total. The estimated ultimate recovery from our sample of 8,294 wells is between 10 and 20 trillion standard cubic feet.

  19. Further Simplification of the Simple Erosion Narrowing Score With Item Response Theory Methodology.

    Science.gov (United States)

    Oude Voshaar, Martijn A H; Schenk, Olga; Ten Klooster, Peter M; Vonkeman, Harald E; Bernelot Moens, Hein J; Boers, Maarten; van de Laar, Mart A F J

    2016-08-01

    To further simplify the simple erosion narrowing score (SENS) by removing scored areas that contribute the least to its measurement precision according to analysis based on item response theory (IRT) and to compare the measurement performance of the simplified version to the original. Baseline and 18-month data of the Combinatietherapie Bij Reumatoide Artritis (COBRA) trial were modeled using longitudinal IRT methodology. Measurement precision was evaluated across different levels of structural damage. SENS was further simplified by omitting the least reliably scored areas. Discriminant validity of SENS and its simplification were studied by comparing their ability to differentiate between the COBRA and sulfasalazine arms. Responsiveness was studied by comparing standardized change scores between versions. SENS data showed good fit to the IRT model. Carpal and feet joints contributed the least statistical information to both erosion and joint space narrowing scores. Omitting the joints of the foot reduced measurement precision for the erosion score in cases with below-average levels of structural damage (relative efficiency compared with the original version ranged 35-59%). Omitting the carpal joints had minimal effect on precision (relative efficiency range 77-88%). Responsiveness of a simplified SENS without carpal joints closely approximated the original version (i.e., all Δ standardized change scores were ≤0.06). Discriminant validity was also similar between versions for both the erosion score (relative efficiency = 97%) and the SENS total score (relative efficiency = 84%). Our results show that the carpal joints may be omitted from the SENS without notable repercussion for its measurement performance. © 2016, American College of Rheumatology.

  20. Bridging Food Webs, Ecosystem Metabolism, and Biogeochemistry Using Ecological Stoichiometry Theory

    Directory of Open Access Journals (Sweden)

    Nina Welti

    2017-07-01

    Full Text Available Although aquatic ecologists and biogeochemists are well aware of the crucial importance of ecosystem functions, i.e., how biota drive biogeochemical processes and vice-versa, linking these fields in conceptual models is still uncommon. Attempts to explain the variability in elemental cycling consequently miss an important biological component and thereby impede a comprehensive understanding of the underlying processes governing energy and matter flow and transformation. The fate of multiple chemical elements in ecosystems is strongly linked by biotic demand and uptake; thus, considering elemental stoichiometry is important for both biogeochemical and ecological research. Nonetheless, assessments of ecological stoichiometry (ES often focus on the elemental content of biota rather than taking a more holistic view by examining both elemental pools and fluxes (e.g., organismal stoichiometry and ecosystem process rates. ES theory holds the promise to be a unifying concept to link across hierarchical scales of patterns and processes in ecology, but this has not been fully achieved. Therefore, we propose connecting the expertise of aquatic ecologists and biogeochemists with ES theory as a common currency to connect food webs, ecosystem metabolism, and biogeochemistry, as they are inherently concatenated by the transfer of carbon, nitrogen, and phosphorous through biotic and abiotic nutrient transformation and fluxes. Several new studies exist that demonstrate the connections between food web ecology, biogeochemistry, and ecosystem metabolism. In addition to a general introduction into the topic, this paper presents examples of how these fields can be combined with a focus on ES. In this review, a series of concepts have guided the discussion: (1 changing biogeochemistry affects trophic interactions and ecosystem processes by altering the elemental ratios of key species and assemblages; (2 changing trophic dynamics influences the transformation and

  1. CULTURAL-ECOLOGICAL THEORY AND THE LANGUAGE EDUCATION OF ROMA CHILDREN

    Directory of Open Access Journals (Sweden)

    Hristo Kyuchukov

    2017-12-01

    Full Text Available The paper presents results from language testing of 70 Roma children from Bulgaria - pupils of grade 1, studying in one of the biggest Roma settlement’s schools in Sofia, “Fakulteta” district. The children were tested using the Peabody Picture Vocabulary Test. The test measures language comprehension and language production of the children at the beginning and end of the school year. Between the first and second testing, the teaching methodology in instruction for the children was changed - a Roma assistant teacher whose task was to use the mother tongue of the children as a communicative tool was introduced to the classes. The results of the children during the second testing were substantially better and they are discussed in the light of the theory of the American anthropologist J. Ogbu, who developed his cultural-ecological theory (CE in the 1980s. The results of the children are analyzed via dispersion analysis using ANOVA. According to Ogbu’s CE theory, the school success of minority children depends on the attitudes of the society at large and the level of community support. The paper also briefly discusses the reason why the de-segregation of the Roma children and their integration into mainstream schools in Bulgaria has largely proved to be a failure.

  2. Ecological theory as a foundation to control pathogenic invasion in aquaculture

    Science.gov (United States)

    De Schryver, Peter; Vadstein, Olav

    2014-01-01

    Detrimental host–pathogen interactions are a normal phenomenon in aquaculture animal production, and have been counteracted by prophylactic use of antibiotics. Especially, the youngest life stages of cultivated aquatic animals are susceptible to pathogen invasion, resulting in disease and mortality. To establish a more sustainable aquatic food production, there is a need for new microbial management strategies that focus on ‘join them' and not the traditional ‘beat them' approaches. We argue that ecological theory could serve as a foundation for developing sustainable microbial management methods that prevent pathogenic disease in larviculture. Management of the water microbiota in aquaculture systems according to ecological selection principles has been shown to decrease opportunistic pathogen pressure and to result in an improved performance of the cultured animals. We hypothesize that manipulation of the biodiversity of the gut microbiota can increase the host's resistance against pathogenic invasion and infection. However, substantial barriers need to be overcome before active management of the intestinal microbiota can effectively be applied in larviculture. PMID:24892581

  3. Quantity and quality limit detritivore growth: mechanisms revealed by ecological stoichiometry and co-limitation theory.

    Science.gov (United States)

    Halvorson, Halvor M; Sperfeld, Erik; Evans-White, Michelle A

    2017-12-01

    Resource quantity and quality are fundamental bottom-up constraints on consumers. Best understood in autotroph-based systems, co-occurrence of these constraints may be common but remains poorly studied in detrital-based systems. Here, we used a laboratory growth experiment to test limitation of the detritivorous caddisfly larvae Pycnopsyche lepida across a concurrent gradient of oak litter quantity (food supply) and quality (phosphorus : carbon [P:C ratios]). Growth increased simultaneously with quantity and quality, indicating co-limitation across the resource gradients. We merged approaches of ecological stoichiometry and co-limitation theory, showing how co-limitation reflected shifts in C and P acquisition throughout homeostatic regulation. Increased growth was best explained by elevated consumption rates and improved P assimilation, which both increased with elevated quantity and quality. Notably, C assimilation efficiencies remained unchanged and achieved maximum 18% at low quantity despite pronounced C limitation. Detrital C recalcitrance and substantive post-assimilatory C losses probably set a minimum quantity threshold to achieve positive C balance. Above this threshold, greater quality enhanced larval growth probably by improving P assimilation toward P-intensive growth. We suggest this interplay of C and P acquisition contributes to detritivore co-limitation, highlighting quantity and quality as potential simultaneous bottom-up controls in detrital-based ecosystems, including under anthropogenic change like nutrient enrichment. © 2017 by the Ecological Society of America.

  4. Critical PO2 is size-independent in insects: implications for the metabolic theory of ecology.

    Science.gov (United States)

    Harrison, Jon F; Klok, C J; Waters, James S

    2014-10-01

    Insects, and all animals, exhibit hypometric scaling of metabolic rate, with larger species having lower mass-specific metabolic rates. The metabolic theory of ecology (MTE) is based on models ascribing hypometric scaling of metabolic rate to constrained O 2 supply systems in larger animals. We compiled critical PO 2 of metabolic and growth rates for more than 40 insect species with a size range spanning four orders of magnitude. Critical PO 2 values vary from far below 21kPa for resting animals to near 21kPa for growing or flying animals and are size-independent, demonstrating that supply capacity matches oxygen demand. These data suggest that hypometric scaling of resting metabolic rate in insects is not driven by constraints on oxygen availability. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. [Measuring water ecological carrying capacity with the ecosystem-service-based ecological footprint (ESEF) method: Theory, models and application].

    Science.gov (United States)

    Jiao, Wen-jun; Min, Qing-wen; Li, Wen-hua; Fuller, Anthony M

    2015-04-01

    Integrated watershed management based on aquatic ecosystems has been increasingly acknowledged. Such a change in the philosophy of water environment management requires recognizing the carrying capacity of aquatic ecosystems for human society from a more general perspective. The concept of the water ecological carrying capacity is therefore put forward, which considers both water resources and water environment, connects socio-economic development to aquatic ecosystems and provides strong support for integrated watershed management. In this paper, the authors proposed an ESEF-based measure of water ecological carrying capacity and constructed ESEF-based models of water ecological footprint and capacity, aiming to evaluate water ecological carrying capacity with footprint methods. A regional model of Taihu Lake Basin was constructed and applied to evaluate the water ecological carrying capacity in Changzhou City which located in the upper reaches of the basin. Results showed that human demand for water ecosystem services in this city had exceeded the supply capacity of local aquatic ecosystems and the significant gap between demand and supply had jeopardized the sustainability of local aquatic ecosystems. Considering aqua-product provision, water supply and pollutant absorption in an integrated way, the scale of population and economy aquatic ecosystems in Changzhou could bear only 54% of the current status.

  6. Class of very simple gauge theories which remain renormalizable even in the limit of infinite gauge coupling constant

    International Nuclear Information System (INIS)

    Kaptanoglu, S.

    1983-01-01

    A class of local gauge theories based on compact semisimple Lie groups is studied in the limit of infinite gauge coupling constant (g = infinity). In general, in this limit, the gauge fields become auxiliary in all gauge theories, and the system develops a richer structure of constraints. Unfortunately for most gauge theories, this limit turns out to be too singular to quantize and the theory ceases to be renormalizable. For a special class of gauge theories, however, where there are no fermions and there is only one multiplet of scalars in the adjoint representation, we prove that a consistent renormalizable quantum theory exists even in this very singular limit. We trace this exceptional behavior to a new local translationlike symmetry in the functional space that this class of gauge models possesses in the limit of infinite gauge coupling constant. By carrying out the constraint analysis, evaluating the Faddeev-Popov-Senjanovic determinant, and doing the functional integrations over the canonical momenta, the gauge fields, and most of the components of the scalar fields, we obtain an extremely simple result with no non-Abelian structure left in it. For example, for the group SU(2), the final answer reduces to the theory of a one-component self-interacting real phi 4 scalar field theory. Throughout this paper, we use functional methods and make no approximations; our results are nonperturbative and exact. We also discuss some of the possible implications of our results

  7. Simple and Multi-collision of an Ellipsoid with Planar Surfaces. Part I: Theory

    Directory of Open Access Journals (Sweden)

    Nicolae–Doru Stănescu

    2017-11-01

    Full Text Available This paper discusses the problem of simultaneous collisions between an ellipsoid and some planar surfaces. The approach is one based on the theory of screws and uses the notion of inertance. The authors consider that the coefficients of restitution are different for each planar surface and they obtain the velocities after the collision. An example concludes the theory.

  8. An investigation of the astronomical theory of the ice ages using a simple climate-ice sheet model

    Science.gov (United States)

    Pollard, D.

    1978-01-01

    The astronomical theory of the Quaternary ice ages is incorporated into a simple climate model for global weather; important features of the model include the albedo feedback, topography and dynamics of the ice sheets. For various parameterizations of the orbital elements, the model yields realistic assessments of the northern ice sheet. Lack of a land-sea heat capacity contrast represents one of the chief difficulties of the model.

  9. Naïveté in novel ecological interactions: lessons from theory and experimental evidence.

    Science.gov (United States)

    Carthey, Alexandra J R; Banks, Peter B

    2014-11-01

    The invasion of alien species into areas beyond their native ranges is having profound effects on ecosystems around the world. In particular, novel alien predators are causing rapid extinctions or declines in many native prey species, and these impacts are generally attributed to ecological naïveté or the failure to recognise a novel enemy and respond appropriately due to a lack of experience. Despite a large body of research concerning the recognition of alien predation risk by native prey, the literature lacks an extensive review of naïveté theory that specifically asks how naïveté between novel pairings of alien predators and native prey disrupts our classical understanding of predator-prey ecological theory. Here we critically review both classic and current theory relating to predator-prey interactions between both predators and prey with shared evolutionary histories, and those that are ecologically 'mismatched' through the outcomes of biological invasions. The review is structured around the multiple levels of naïveté framework of Banks & Dickman (2007), and concepts and examples are discussed as they relate to each stage in the process from failure to recognise a novel predator (Level 1 naïveté), through to appropriate (Level 2) and effective (Level 3) antipredator responses. We discuss the relative contributions of recognition, cue types and the implied risk of cues used by novel alien and familiar native predators, to the probability that prey will recognise a novel predator. We then cover the antipredator response types available to prey and the factors that predict whether these responses will be appropriate or effective against novel alien and familiar native predators. In general, the level of naïveté of native prey can be predicted by the degree of novelty (in terms of appearance, behaviour or habitat use) of the alien predator compared to native predators with which prey are experienced. Appearance in this sense includes cue types

  10. The Development of the Functional Literacy Experience Scale Based upon Ecological Theory (FLESBUET) and Validity-Reliability Study

    Science.gov (United States)

    Özenç, Emine Gül; Dogan, M. Cihangir

    2014-01-01

    This study aims to perform a validity-reliability test by developing the Functional Literacy Experience Scale based upon Ecological Theory (FLESBUET) for primary education students. The study group includes 209 fifth grade students at Sabri Taskin Primary School in the Kartal District of Istanbul, Turkey during the 2010-2011 academic year.…

  11. Modern money theory and ecological tax reform: A functional finance approach to energy conservation

    Science.gov (United States)

    McConnell, Scott L. B.

    This dissertation contributes to heterodox economics by developing a theoretical and policy-relevant link that will promote the conservation of energy while driving the value of the domestic currency. The analysis relies upon the theoretical foundation of modern money theory and functional finance, which states that "taxes-drive-money" where the value of a sovereign nation's currency is imputed through the acceptance by the sovereign nation of the currency in payment of taxation. This theoretical perspective lends itself to various public policy prescriptions, such as government employment policies or the employer of last resort (ELR), which has been discussed at length elsewhere (Wray 1998; Tcherneva 2007, Forstater 2003). This research contributes to this overall program by arguing that the basis for taxation under modern money theory allows public policy makers various alternatives regarding the make-up of the tax system in place. In particular, following functional finance, taxes do not have the sole purpose of paying for government spending, but rather drive the value of the currency and may be designed to perform other functions as well, such as penalizing socially undesirable behavior. The focus in this dissertation is on the amelioration of pollution and increasing energy conservation. The research question for this dissertation is this: what federally implemented tax would best serve the multiple criteria of 1) driving the value of the currency, 2) promoting energy conservation and 3) ameliorating income and wealth disparities inherent in a monetary production economy? This dissertation provides a suggestion for such a tax that would be part of a much larger overall policy program based upon the tenets of modern money theory and functional finance. Additionally, this research seeks to provide an important theoretical contribution to the emerging Post Keynesian and ecological economics dialog.

  12. Issues in the sphere of ecology safety and resources for their solution in the light of political ecology theory

    Directory of Open Access Journals (Sweden)

    Vladimir G. Tyminskiy

    2017-03-01

    Full Text Available Objective to analyze the world experience of forming the paradigm of political ecology in the aspect of environmental safety. Methods dialectical method of cognition detailing logical generalization. Results the article formulates conclusions about the topicality of the environmental security issues confirming in particular by the nature of the changes in consumer demand and environmentally responsible behavior of a certain part of the population. The global trends are identified in the formation and development of international institutions in the field of political ecology scientific institutes and laboratories working in this field. The analysis of world experience of forming the paradigm of political ecology has shown that currently an attempt is made to introduce nature into the economic relationship as one of their subjects emphasizing the ambiguous attitude of scientists to ecosystem services. It is revealed that in Russia and abroad the issues of environmental security are studied by a significant number of scientific educational and public organizations. The most important trends are the shift in emphasis from the natural environment to humans and the systematization and expansion of the list of threats to environmental security. The article also analyzes the main parameters of ecological safety of Russia and formulates conclusions about the poor state of most ecosystems and quotecophobicquot industrial infrastructure. Also the problems of interregional cooperation in the environmental field are defined as well as the negative impact of transnational corporations on environmental safety. The main tasks of political ecology in the framework of the national program of socioeconomic development of Russia are defined. The conclusion is made about the necessity to formulate the problem and describe the principles of a comprehensive program of environmental safety taking into account the geological security within the national security

  13. A simple solvable model of quantum field theory of open strings

    International Nuclear Information System (INIS)

    Kazakov, V.A.; AN SSSR, Moscow

    1990-01-01

    A model of quantum field theory of open strings without any embedding (D=0) is solved. The world sheets of interacting strings are represented by dynamical planar graphs with dynamical holes of arbitrary sizes. The phenomenon of spontaneous tearing of the world sheet is noticed, which gives a singularity at zero coupling constant of string interaction. This phenomenon can be considered as a nonperturbative effect, similar to renormalons in planar field theories and is closely related to the α' → 0 limit of string field theories. (orig.)

  14. Theory of mind in remitted bipolar disorder: Younger patients struggle in tasks of higher ecological validity.

    Science.gov (United States)

    Feyerabend, Julia; Lüttke, Stefan; Grosse-Wentrup, Fabienne; Wolter, Sibylla; Hautzinger, Martin; Wolkenstein, Larissa

    2018-04-15

    To date, research concerning Theory of Mind (ToM) in remitted bipolar disorder (rBD) has yielded inconclusive results. This may be a result of methodological shortcomings and the failure to consider relevant third variables. Furthermore, studies using ecologically valid stimuli are rare. This study examines ToM in rBD patients, using ecologically valid stimuli. Additionally, the effects of sad mood induction (MI) as well as of age and gender are considered. The sample comprises N = 44 rBD patients (rBDPs) and N = 40 healthy controls (HCs). ToM decoding is assessed using the Cambridge Mindreading Face-Voice-Battery (CAM) and ToM reasoning using the Movie for the Assessment of Social Cognition (MASC). Both tasks were divided into two parts to conduct one part with and one without MI. While across the whole sample there was no evidence that rBDPs and HCs differed in ToM decoding or reasoning, in the younger subsample (age < 45) rBDPs performed worse than HCs in ToM decoding. While MI negatively influenced reasoning in both groups, gender had no effect. Most patients in this study had a high level of social functioning, limiting the generalizability of the results. As important social steps have to be undertaken before middle-age, the decoding deficits in younger rBDPs might be of particular importance not only for social functioning but also for the course of illness. Furthermore, this age-related deficit may explain the inconclusive findings that have been reported so far. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Eliminating infinities in the λφ4 theory by simple scaling

    International Nuclear Information System (INIS)

    Aragao, Cristiane M.L. de; Carneiro, C.E.I.

    2006-01-01

    We present an alternative method to remove infinities in the perturbative φ 4 theory. In our method, the renormalization is performed in two stages. Firstly, the infinities are eliminated by rescaling the Lagrangian. The Green functions obtained from this rescaled Lagrangian are finite to all orders in perturbation. Secondly, we fix the values of parameters of the resulting finite theory at a certain mass scale by using the standard renormalization conditions. This second stage allows us to derive renormalization equations which yields the critical behavior of the theory. We show that our method does not change the critical behavior of the λφ 4 theory in 4-ε dimensions. In particular, we recover the usual critical exponents

  16. Land ecological security assessment for Yancheng city based on catastrophe theory

    Directory of Open Access Journals (Sweden)

    Wang Liang

    2014-07-01

    Full Text Available Based on actual land use in Yancheng city, this paper establishes the ecological security of the land index system from the perspectives of economy, society and ecological environment. Using the catastrophe theory and pressure-state-response (PSR model, the purpose of the research was to judge the degree of land ecological security in Yancheng city from 2002 to 2011 and determine the requirements to ensure the sustainable development of this region. The results showed that over the ten years, the pressure, state, response and synthetic values of the land ecological security were evaluated as safe in 2003 and 2007 and at middle level in 2002 and for 2004 to 2006 and then dropped to insecure for 2008 to 2009 and very insecure for 2011 to 2012. The ecological security level and circumstance of land use in Yancheng city has generally declined. During this period, the land use pattern of Yancheng city was under tremendous pressure from the conflict between rapid urbanization and economic development, as well as conservation and rehabilitation of the eco-environment. This research shows that conditions for the land ecosystems of Yancheng city are not optimistic and, as such, should draw the attention of responsible government departments. Future policy options should aim to mitigate these problems through the control of population growth and the improvement in quality of life, protection of wetland and forest land, application of scientific concepts of development, coordination of economic development and land utility, and strengthening the control functions of land-use planning.   Resumen De acuerdo con el uso actual del suelo en la ciudad de Yancheng, en el este de China, este artículo establece la seguridad ecológica del sistema de tierras desde las perspectivas económica, social y ecológica. A partir de la Teoría de las Catástrofes y el modelo ambiental de presión-estado-respuesta (PSR, el propósito de esta investigación fue determinar

  17. Forest Productivity and Diversity: Using Ecological Theory and Landscape Models to Guide Sustainable Forest Management

    Energy Technology Data Exchange (ETDEWEB)

    Huston, M.A.

    1998-11-01

    Sustainable forest management requires maintaining or increasing ecosystem productivity, while preserving or restoring natural levels of biodiversity. Application of general concepts from ecological theory, along with use of mechanistic, landscape-based computer models, can contribute to the successful achievement of both of these objectives. Ecological theories based on the energetics and dynamics of populations can be used to predict the general distribution of individual species, the diversity of different types of species, ecosystem process rates and pool sizes, and patterns of spatial and temporal heterogeneity over a broad range of environmental conditions. This approach requires subdivision of total biodiversity into functional types of organisms, primarily because different types of organisms respond very differently to the spatial and temporal variation of environmental conditions on landscapes. The diversity of species of the same functional type (particularly among plants) tends to be highest at relatively low levels of net primary productivity, while the total number of different functional types (particularly among animals) tends to be highest at high levels of productivity (e.g., site index or potential net primary productivity). In general, the diversity of animals at higher trophic levels (e.g., predators) reaches its maximum at much higher levels of productivity than the diversity of lower trophic levels (e.g., plants). This means that a single environment cannot support high diversity of all types of organisms. Within the framework of the general patterns described above, the distributions, population dynamics, and diversity of organisms in specific regions can be predicted more precisely using a combination of computer simulation models and GIS data based on satellite information and ground surveys. Biophysical models that use information on soil properties, climate, and hydrology have been developed to predict how the abundance and spatial

  18. The fermion content of the Standard Model from a simple world-line theory

    Energy Technology Data Exchange (ETDEWEB)

    Mansfield, Paul, E-mail: P.R.W.Mansfield@durham.ac.uk

    2015-04-09

    We describe a simple model that automatically generates the sum over gauge group representations and chiralities of a single generation of fermions in the Standard Model, augmented by a sterile neutrino. The model is a modification of the world-line approach to chiral fermions.

  19. Habitats: A Simple Way to Bridge Artifacts, Professions, and Theories in Ubiquitous Design

    DEFF Research Database (Denmark)

    Brynskov, Martin; Kramp, Gunnar

    2007-01-01

    and comparing two empirical case-studies, one about life and death (emergency response at major incidents) and one about playfulness (children’s pervasive play and gaming), and (3) discussing the usefulness of using habitats. The result is a number of real-world examples where we argue that using habitats...... as a simple common ground seems to be useful for professionals coming from quite different traditions....

  20. Density nonlinearities and a field theory for the dynamics of simple fluids

    OpenAIRE

    Mazenko, Gene F.; Yeo, Joonhyun

    1994-01-01

    We study the role of the Jacobian arising from a constraint enforcing the nonlinear relation: ${\\bf g}=\\rho{\\bf V}$, where $\\rho,\\: {\\bf g}$ and ${\\bf V}$ are the mass density, the momentum density and the local velocity field, respectively, in the field theoretic formulation of the nonlinear fluctuating hydrodynamics of simple fluids. By investigating the Jacobian directly and by developing a field theoretic formulation without the constraint, we find that no changes in dynamics result as co...

  1. Urban ecology in a developing world: why advanced socioecological theory needs Africa.

    Science.gov (United States)

    McHale, Melissa R; Bunn, David N; Pickett, Steward Ta; Twine, Wayne

    2013-12-01

    Socioecological theory, developed through the study of urban environments, has recently led to a proliferation of research focusing on comparative analyses of cities. This research emphasis has been concentrated in the more developed countries of the Northern Hemisphere (often referred to as the "Global North"), yet urbanization is now occurring mostly in the developing world, with the fastest rates of growth in sub-Saharan Africa. Countries like South Africa are experiencing a variety of land-cover changes that may challenge current assumptions about the differences between urban and rural environments and about the connectivity of these dynamic socioecological systems. Furthermore, questions concerning ecosystem services, landscape preferences, and conservation - when analyzed through rural livelihood frameworks - may provide insights into the social and ecological resilience of human settlements. Increasing research on urban development processes occurring in Africa, and on patterns of kinship and migration in the less developed countries of the "Global South", will advance a more comprehensive worldview of how future urbanization will influence the progress of sustainable societies.

  2. Activity theory and genre ecology: Conceptual tools for understanding technical communication

    Directory of Open Access Journals (Sweden)

    Winberg, Christine

    2005-12-01

    Full Text Available This paper reports on a year-long project in an architectural technology department, which studied students’ oral language development in plenary discussions in a first year History and Appreciation of Architecture course. Data was obtained by videotaping classroom activities, and by interviewing the lecturer and students who were participants in the course. The data was analysed, using categories suggested by Activity Theory. The category of ‘rules’ was selected from the activity system for further analysis, using a Genre Ecology approach. The findings of the study show how technical communication is managed within a classroom based activity system comprising lecturer and students, and graphic and verbal texts, in a context of learning. Learning, teaching, and expert discourses of the architectural review genre interact and are negotiated by participants. Through participation in plenary discussion, students from diverse backgrounds contribute to one another’s experience of architectural design, and by valuing and responding to students’ contributions, the lecturer facilitates students’ understanding of the ‘rules’ of architectural communication, and enables students to access an expanded repertoire of the genre of architectural review.

  3. Ecology of tern flight in relation to wind, topography and aerodynamic theory.

    Science.gov (United States)

    Hedenström, Anders; Åkesson, Susanne

    2016-09-26

    Flight is an economical mode of locomotion, because it is both fast and relatively cheap per unit of distance, enabling birds to migrate long distances and obtain food over large areas. The power required to fly follows a U-shaped function in relation to airspeed, from which context dependent 'optimal' flight speeds can be derived. Crosswinds will displace birds away from their intended track unless they make compensatory adjustments of heading and airspeed. We report on flight track measurements in five geometrically similar tern species ranging one magnitude in body mass, from both migration and the breeding season at the island of Öland in the Baltic Sea. When leaving the southern point of Öland, migrating Arctic and common terns made a 60° shift in track direction, probably guided by a distant landmark. Terns adjusted both airspeed and heading in relation to tail and side wind, where coastlines facilitated compensation. Airspeed also depended on ecological context (searching versus not searching for food), and it increased with flock size. Species-specific maximum range speed agreed with predicted speeds from a new aerodynamic theory. Our study shows that the selection of airspeed is a behavioural trait that depended on a complex blend of internal and external factors.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'. © 2016 The Author(s).

  4. K-theory for certain extension algebras of purely infinite simple C ...

    Indian Academy of Sciences (India)

    In the 1960s, Atiyah and Hirzebruch developed the K-theory which is based on the work .... all projections in E\\B. Then P satisfies the following conditions: (1) : If p, q ∈ P ..... London/Singapore/Hong Kong/Bangalore: World Scientific) (2001).

  5. The use of ecological theory and autecological datasets in studies of endangered plant and animal species and communities

    Directory of Open Access Journals (Sweden)

    Hodgson, John G.

    1991-12-01

    Full Text Available Few, if any, European habitats have been unaffected by modern land-use and the problems of conserving the diversity of the European flora and fauna are both urgent and immense. This paper describes a simple method for analyzing floristic change that is hoped will prove useful for assessing the nature and severity of these threats. The method involves the use of ecological theory and the collection of simple autecological data. Examples are given to illustrate how this approach can be used both to identify reasons for floristic change and to provide functional analyses of phytosociological data. Also, as a result of analyses of reasons for commonness and rarity in butterflies and birds, it is argued that similar functional interpretations of zoological datasets may soon be possible.

    [es] Considerando que prácticamente todos los hábitats de Europa han sido afectados por los usos de la tierra modernos, la conservación de la diversidad de su flora y fauna se presenta como un problema muy grave y urgente. En este artículo se describe un método simple para analizar cambios florísticos, contemplando el uso de la teoría ecológica y la colección de datos autoecológicos sencillos. Dicho método constituye una herramienta para evaluar la naturaleza y severidad de procesos de pérdida de la diversidad biológica. Se dan ejemplos ilustrando el uso de este enfoque en la identificación de las causas de cambios florísticos y en el análisis funcional de datos fitosociológicos. Se presentan, además, las razones que explican la presencia de especies raras o muy comunes de mariposas y aves. A partir de estos últimos resultados, se concluye que en breve será posible realizar una interpretación funcional similar de datos zoológicos.
    [de] Nur wenige, wenn überhaupt, der Lebensrame in Europa sind unberührt von moderner Landnutzung und die Probleme der Erhaltung der Vielfalt in der Flora und Fauna sind sowohl dringend als auch immens

  6. A simple fish-based approach to assess the ecological quality of freshwater reservoirs in Central Europe

    Czech Academy of Sciences Publication Activity Database

    Blabolil, Petr; Říha, Milan; Ricard, Daniel; Peterka, Jiří; Prchalová, Marie; Vašek, Mojmír; Čech, Martin; Frouzová, Jaroslava; Jůza, Tomáš; Muška, Milan; Tušer, Michal; Draštík, Vladislav; Sajdlová, Zuzana; Šmejkal, Marek; Vejřík, Lukáš; Matěna, Josef; Boukal, D.S.; Ritterbusch, D.; Kubečka, Jan

    2017-01-01

    Roč. 418, November (2017), č. článku 53. ISSN 1961-9502 R&D Projects: GA MŠk(CZ) EE2.3.20.0204; GA ČR(CZ) GA15-01625S; GA MŠk(CZ) LM2015075; GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : artificial lakes * fish indicators * eutrophication * gillnets * index sensitivity Subject RIV: EH - Ecology, Behaviour OBOR OECD: Marine biology, freshwater biology, limnology Impact factor: 1.217, year: 2016

  7. An ecological compensation standard based on emergy theory for the Xiao Honghe River Basin.

    Science.gov (United States)

    Guan, Xinjian; Chen, Moyu; Hu, Caihong

    2015-01-01

    The calculation of an ecological compensation standard is an important, but also difficult aspect of current ecological compensation research. In this paper, the factors affecting the ecological-economic system in the Xiao Honghe River Basin, China, including the flow of energy, materials, and money, were calculated using the emergy analysis method. A consideration of the relationships between the ecological-economic value of water resources and ecological compensation allowed the ecological-economic value to be calculated. On this basis, the amount of water needed for dilution was used to develop a calculation model for the ecological compensation standard of the basin. Using the Xiao Honghe River Basin as an example, the value of water resources and the ecological compensation standard were calculated using this model according to the emission levels of the main pollutant in the basin, chemical oxygen demand. The compensation standards calculated for the research areas in Xipin, Shangcai, Pingyu, and Xincai were 34.91 yuan/m3, 32.97 yuan/m3, 35.99 yuan/m3, and 34.70 yuan/m3, respectively, and such research output would help to generate and support new approaches to the long-term ecological protection of the basin and improvement of the ecological compensation system.

  8. On the independent particle approximation of Gauge theories: a simple example

    International Nuclear Information System (INIS)

    Palladino, B.E.

    1992-08-01

    In this work, the independent particle model formulation is studied as a mean-field approximation of gauge theories using the path integral approach in the framework of quantum electrodynamics in 1+1 dimensions. It is shown how a mean-field approximation scheme can be applied to fit an effective potential to an independent particle model, building a straightforward relation between the model and the associated gauge field theory. An example is made considering the problem of massive Dirac fermions on a line, the so called massive Schwinger model. An interesting result is found, indicating a behaviour of screening of the charges in the relativistic limit of strong coupling. A forthcoming application of the method developed to confining potentials in independent quark models for QCD is in view and is briefly discussed. (author)

  9. Simple proof of the impossibility of bit commitment in generalized probabilistic theories using cone programming

    Science.gov (United States)

    Sikora, Jamie; Selby, John

    2018-04-01

    Bit commitment is a fundamental cryptographic task, in which Alice commits a bit to Bob such that she cannot later change the value of the bit, while, simultaneously, the bit is hidden from Bob. It is known that ideal bit commitment is impossible within quantum theory. In this work, we show that it is also impossible in generalized probabilistic theories (under a small set of assumptions) by presenting a quantitative trade-off between Alice's and Bob's cheating probabilities. Our proof relies crucially on a formulation of cheating strategies as cone programs, a natural generalization of semidefinite programs. In fact, using the generality of this technique, we prove that this result holds for the more general task of integer commitment.

  10. Simple kinetic theory model of reactive collisions. IV. Laboratory fixed orientational cross sections

    International Nuclear Information System (INIS)

    Evans, G.T.

    1987-01-01

    The differential orientational cross section, obtainable from molecular beam experiments on aligned molecules, is calculated using the line-of-normals model for reactive collisions involving hard convex bodies. By means of kinetic theory methods, the dependence of the cross section on the angle of attack γ 0 is expressed in a Legendre function expansion. Each of the Legendre expansion coefficients is given by an integral over the molecule-fixed cross section and functions of the orientation dependent threshold energy

  11. EMC and the printed circuit board design theory and layout made simple

    CERN Document Server

    Montrose, Mark I

    1999-01-01

    "This reference text shows how and why RF energy is created within a printed circuit board, and the manner in which propagation occurs. With thorough explanations, this book enables engineers to grasp both the fundamentals of EMC theory and signal integrity, along with the mitigation process needed to prevent an EMC event while maintaining optimal functionality for low- and high-technology products. Mr. Montrose also shows the relationship between time and frequency domains, helping one meet mandatory compliance requirements."--Jacket.

  12. Equation of state of a hard core fluid with a two-Yukawa tail: toward a simple analytic theory

    International Nuclear Information System (INIS)

    Jedrzejek, C.

    1980-01-01

    Thermodynamic properties of simple fluids are calculated using variational theory for a system of hard-core potential with a two-Yukawa tail. Likewise one Yukawa-tail case the working formulas are analytic. Five parameters of the two Yukawa system are chosen so as to get the best fit to a real argon potential or an ''argon-like'' Lennard-Jones potential. The results are fairly good in light of the extreme simplicity of the method. The discrepancies result from using the variational method and a different shape of Yukawa type potential in comparision to the real argon and Lennard-Jones potentials. (author)

  13. Computationally simple, analytic, closed form solution of the Coulomb self-interaction problem in Kohn Sham density functional theory

    International Nuclear Information System (INIS)

    Gonis, Antonios; Daene, Markus W.; Nicholson, Don M.; Stocks, George Malcolm

    2012-01-01

    We have developed and tested in terms of atomic calculations an exact, analytic and computationally simple procedure for determining the functional derivative of the exchange energy with respect to the density in the implementation of the Kohn Sham formulation of density functional theory (KS-DFT), providing an analytic, closed-form solution of the self-interaction problem in KS-DFT. We demonstrate the efficacy of our method through ground-state calculations of the exchange potential and energy for atomic He and Be atoms, and comparisons with experiment and the results obtained within the optimized effective potential (OEP) method.

  14. Common psychotic symptoms can be explained by the theory of ecological perception.

    Science.gov (United States)

    Golembiewski, Jan Alexander

    2012-01-01

    The symptoms of psychiatric illness are diverse, as are the causes of the conditions that cause them. Yet, regardless of the heterogeneity of cause and presentation, a great deal of symptoms can be explained by the failure of a single perceptual function--the reprocessing of ecological perception. It is a central tenet of the ecological theory of perception that we perceive opportunities to act. It has also been found that perception automatically causes actions and thoughts to occur unless this primary action pathway is inhibited. Inhibition allows perceptions to be reprocessed into more appropriate alternative actions and thoughts. Reprocessing of this kind takes place over the entire frontal lobe and it renders action optional. Choice about what action to take (if any) is the basis for the feeling of autonomy and ultimately for the sense-of-self. When thoughts and actions occur automatically (without choice) they appear to originate outside of the self, thereby providing prima facie evidence for some of the bizarre delusions that define schizophrenia such as delusional misidentification, delusions of control and Cotard's delusion. Automatic actions and thoughts are triggered by residual stimulation whenever reprocessing is insufficient to balance automatic excitatory cues (for whatever reason). These may not be noticed if they are neutral and therefore unimportant or where actions and thoughts have a positive bias and are desirable. Responses to negative stimulus, on the other hand, are always unwelcome, because the actions that are triggered will carry the negative bias. Automatic thoughts may include spontaneous positive feelings of love and joy, but automatic negative thoughts and visualisations are experienced as hallucinations. Not only do these feel like they emerge from elsewhere but they carry a negative bias (they are most commonly critical, rude and are irrationally paranoid). Automatic positive actions may include laughter and smiling and these are

  15. Molecular evolutionary rates are not correlated with temperature and latitude in Squamata: an exception to the metabolic theory of ecology?

    Science.gov (United States)

    Rolland, Jonathan; Loiseau, Oriane; Romiguier, Jonathan; Salamin, Nicolas

    2016-05-20

    The metabolic theory of ecology stipulates that molecular evolutionary rates should correlate with temperature and latitude in ectothermic organisms. Previous studies have shown that most groups of vertebrates, such as amphibians, turtles and even endothermic mammals, have higher molecular evolutionary rates in regions where temperature is high. However, the association between molecular evolutionary rates and temperature or latitude has never been tested in Squamata. We used a large dataset including the spatial distributions and environmental variables for 1,651 species of Squamata and compared the contrast of the rates of molecular evolution with the contrast of temperature and latitude between sister species. Using major axis regressions and a new algorithm to choose independent sister species pairs, we found that temperature and absolute latitude were not associated with molecular evolutionary rates. This absence of association in such a diverse ectothermic group questions the mechanisms explaining current pattern of species diversity in Squamata and challenges the presupposed universality of the metabolic theory of ecology.

  16. Density functional theory of simple polymers in a slit pore. III. Surface tension

    International Nuclear Information System (INIS)

    Hooper, Justin B.; McCoy, John D.; Curro, John G.; Swol, Frank van

    2000-01-01

    In a previous study of tangent hard-site chains near a surface, the inhomogeneous density profiles were found through density functional theory. In the current study, the surface tensions of these systems are found from the results of the previous study through a thermodynamic integration. The calculated surface tensions are then compared to those found directly through computer simulation. Both the surface tension and surface excess for polymeric systems are shown to differ qualitatively from those of atomic systems, although certain similarities are seen at high densities. (c) 2000 American Institute of Physics

  17. Simple descriptors for proton-conducting perovskites from density functional theory

    DEFF Research Database (Denmark)

    Bork, Nicolai Christian; Bonanos, Nikolaos; Rossmeisl, Jan

    2010-01-01

    series of (pseudo)cubic perovskites, ABO3, have been investigated using density functional theory calculations. The structures have been optimized and thermodynamic properties and activation energies for the relevant steps of the hydrogen/proton diffusion mechanism have been calculated using...... the nudged elastic band path technique. We find a strong correlation between the O-H binding energy for hydrogen/proton uptake in perovskites and the energy barriers involved in the observed Grotthuss-type diffusion process. We demonstrate the possibility of estimating diffusion rates based on O-H binding...

  18. Theory of finite periodic systems - I: General expressions and various simple and illustrative examples

    International Nuclear Information System (INIS)

    Pereyra, Pedro; Castillo, Edith

    2001-09-01

    A comprehensive presentation of a new approach to finite periodic systems is given. The novel and general expressions obtained here, allow simple and precise calculations of various physical quantities characteristic of crystalline systems. Transmission amplitudes through n-cell multichannel quantum systems are rigorously derived. General expressions for several physical quantities are entirely expressed in terms of single-cell amplitudes and a new class of polynomials p N,n . Besides the general expressions, we study some superlattice properties as the band structure and its relation with the phase coherence phenomena, the level density and the Kronig-Penney model as its continuous espectrum limit. Bandstructure tailoring, optical multilayer systems, resonant energies and functions and channel-mixing effects in multichannel transport process are also analysed in the light of the new approach. (author)

  19. Trait-based plant ecology: moving towards a unifying species coexistence theory : Features of the Special Section.

    Science.gov (United States)

    Escudero, Adrián; Valladares, Fernando

    2016-04-01

    Functional traits are the center of recent attempts to unify key ecological theories on species coexistence and assembling in populations and communities. While the plethora of studies on the role of functional traits to explain patterns and dynamics of communities has rendered a complex picture due to the idiosyncrasies of each study system and approach, there is increasing evidence on their actual relevance when aspects such as different spatial scales, intraspecific variability and demography are considered.

  20. Anomaly cancellation in effective supergravity theories from the heterotic string: Two simple examples

    Directory of Open Access Journals (Sweden)

    Mary K. Gaillard

    2018-02-01

    Full Text Available We use Pauli–Villars regularization to evaluate the conformal and chiral anomalies in the effective field theories from Z3 and Z7 compactifications of the heterotic string without Wilson lines. We show that parameters for Pauli–Villars chiral multiplets can be chosen in such a way that the anomaly is universal in the sense that its coefficient depends only on a single holomorphic function of the three diagonal moduli. It is therefore possible to cancel the anomaly by a generalization of the four-dimensional Green–Schwarz mechanism. In particular we are able to reproduce the results of a string calculation of the four-dimensional chiral anomaly for these two models.

  1. Anomaly cancellation in effective supergravity theories from the heterotic string: Two simple examples

    Science.gov (United States)

    Gaillard, Mary K.; Leedom, Jacob

    2018-02-01

    We use Pauli-Villars regularization to evaluate the conformal and chiral anomalies in the effective field theories from Z3 and Z7 compactifications of the heterotic string without Wilson lines. We show that parameters for Pauli-Villars chiral multiplets can be chosen in such a way that the anomaly is universal in the sense that its coefficient depends only on a single holomorphic function of the three diagonal moduli. It is therefore possible to cancel the anomaly by a generalization of the four-dimensional Green-Schwarz mechanism. In particular we are able to reproduce the results of a string calculation of the four-dimensional chiral anomaly for these two models.

  2. Study of the reflection of fast neutrons by a simple theory of shock. Application to iron

    International Nuclear Information System (INIS)

    Devillers, Christian; Hasselin, Gilbert

    1964-10-01

    By using a first shock theory, the authors report the calculation of an albedo current for fast neutrons, i.e. the rate between the reflected current per cm 2 of plate and the incident current on the same cm 2 . They also compute the spectrum and the angular distribution of reflected neutrons. These calculations are performed by means of three specific software: Psyche 1 for the determination of the albedo due to elastic scattering, and Psyche 2 and 3 for inelastic scattering (the first one addresses incident neutrons with an energy 0.86 and 5 MeV, and the second one the 5-12 MeV energy band). Hypotheses for each calculation are presented, as well as calculation principles and methods. Results are briefly presented and discussed in terms of albedo evolution with respect to incidence and to plate thickness

  3. Equilibrium properties of dense hydrogen isotope gases based on the theory of simple fluids.

    Science.gov (United States)

    Kowalczyk, Piotr; MacElroy, J M D

    2006-08-03

    We present a new method for the prediction of the equilibrium properties of dense gases containing hydrogen isotopes. The proposed approach combines the Feynman-Hibbs effective potential method and a deconvolution scheme introduced by Weeks et al. The resulting equations of state and the chemical potentials as functions of pressure for each of the hydrogen isotope gases depend on a single set of Lennard-Jones parameters. In addition to its simplicity, the proposed method with optimized Lennard-Jones potential parameters accurately describes the equilibrium properties of hydrogen isotope fluids in the regime of moderate temperatures and pressures. The present approach should find applications in the nonlocal density functional theory of inhomogeneous quantum fluids and should also be of particular relevance to hydrogen (clean energy) storage and to the separation of quantum isotopes by novel nanomaterials.

  4. Wild kernels for higher K-theory of division and semi-simple algebras

    International Nuclear Information System (INIS)

    Quo Xuejun; Kuku, Aderemi

    2003-06-01

    Let Σ be a semi-simple algebra over a number field F. In this paper, we prove that for all n ≥ 0, the wild kernel WK n (Σ):Ker(K n (Σ) → Π finiteυ K n (Σ υ )) is contained in the torsion part of the image of the natural homomorphism K n (Λ) → K n (Σ), where Λ is a maximal order in Σ. In particular, WK n (Σ) is finite. In the process, we prove that if Λ is a maximal order in a central division algebra D over F, then the kernel of the reduction map K 2n-1 (Λ) → π υ Π finiteυ K 2n-1 (d υ ) is finite. In paragraph 3 we investigate the connections between WK n (D) and div(K n (D)) and prove that divK 2 (Σ) is a subset of WK 2 (Σ); if the index of D is square free, then div(K 2 (D)) ≅ div(K 2 (F)), WK 2 (F) ≅ WK 2 (D) and vertical bar WK 2 (D)/div(K 2 (D)) vertical bar ≤ 2. Finally we prove that if D is a central division algebra over F with [D : F] = m 2 , then (1) div(K n (D)) l = WK n (D) l for all odd primes I and n ≤ 2; (2) if I does not divide m, then div(K 3 (D)) l = WK 3 (D) l = 0; (3) if F = Q and I does not divide m, then div(K n (D)) l is a subset of WK n (D) l for all n. (author)

  5. Analysis of ensemble learning using simple perceptrons based on online learning theory

    Science.gov (United States)

    Miyoshi, Seiji; Hara, Kazuyuki; Okada, Masato

    2005-03-01

    Ensemble learning of K nonlinear perceptrons, which determine their outputs by sign functions, is discussed within the framework of online learning and statistical mechanics. One purpose of statistical learning theory is to theoretically obtain the generalization error. This paper shows that ensemble generalization error can be calculated by using two order parameters, that is, the similarity between a teacher and a student, and the similarity among students. The differential equations that describe the dynamical behaviors of these order parameters are derived in the case of general learning rules. The concrete forms of these differential equations are derived analytically in the cases of three well-known rules: Hebbian learning, perceptron learning, and AdaTron (adaptive perceptron) learning. Ensemble generalization errors of these three rules are calculated by using the results determined by solving their differential equations. As a result, these three rules show different characteristics in their affinity for ensemble learning, that is “maintaining variety among students.” Results show that AdaTron learning is superior to the other two rules with respect to that affinity.

  6. A simple exposure-time theory for all time-nonlocal transport formulations and beyond.

    Science.gov (United States)

    Ginn, T. R.; Schreyer, L. G.

    2016-12-01

    -differential equations, and so on. Because the exposure-time approach is both simple and localized, it provides a promising platform for launching forays into non-Markovian and/or nonlinear processes and into upscaling age-dependent multicomponent reaction systems.

  7. Future Directions for Dissemination and Implementation Science: Aligning Ecological Theory and Public Health to Close the Research to Practice Gap.

    Science.gov (United States)

    Atkins, Marc S; Rusch, Dana; Mehta, Tara G; Lakind, Davielle

    2016-01-01

    Dissemination and implementation science (DI) has evolved as a major research model for children's mental health in response to a long-standing call to integrate science and practice and bridge the elusive research to practice gap. However, to address the complex and urgent needs of the most vulnerable children and families, future directions for DI require a new alignment of ecological theory and public health to provide effective, sustainable, and accessible mental health services. We present core principles of ecological theory to emphasize how contextual factors impact behavior and allow for the reciprocal impact individuals have on the settings they occupy, and an alignment of these principles with a public health model to ensure that services span the prevention to intervention continuum. We provide exemplars from our ongoing work in urban schools and a new direction for research to address the mental health needs of immigrant Latino families. Through these examples we illustrate how DI can expand its reach by embedding within natural settings to build on local capacity and indigenous resources, incorporating the local knowledge necessary to more substantively address long-standing mental health disparities. This paradigm shift for DI, away from an overemphasis on promoting program adoption, calls for fitting interventions within settings that matter most to children's healthy development and for utilizing and strengthening available community resources. In this way, we can meet the challenge of addressing our nation's mental health burden by supporting the needs and values of families and communities within their own unique social ecologies.

  8. The social ecology of resolving family conflict among West African immigrants in New York: a grounded theory approach.

    Science.gov (United States)

    Rasmussen, Andrew; Chu, Tracy; Akinsulure-Smith, Adeyinka M; Keatley, Eva

    2013-09-01

    The current study employs a grounded theory approach to examine West African immigrants' resolution of parent-child conflict and intimate partner conflict. Data from 59 participants present an interactive social ecological framework, where a lack of resolution at one level results in attempts to resolve problems at higher levels. Four levels are identified within West African immigrants' problem solving ecology, each with specific actors in positions of authority: individual/dyadic (parents and spouses), extended family (which includes distant relatives and relatives living in home countries), community leadership (non-family elders and religious leaders), and state authorities. From participants' descriptions of family challenges emerged a picture of a social ecology in flux, with traditional, socially conservative modes of resolving family conflict transposed across migration into the more liberal and state-oriented familial context of the United States. This transposition results in a loss spiral for the traditional social ecology, differentially affecting individual actors within families. Implications for helping professionals working with new immigrant communities include identifying variability in openness to adapting structures that are not working well (e.g., patriarchal protection of abusive husbands) and supporting structures known to be associated with well being (e.g., collective monitoring of youth).

  9. Fractal Hypothesis of the Pelagic Microbial Ecosystem—Can Simple Ecological Principles Lead to Self-Similar Complexity in the Pelagic Microbial Food Web?

    Science.gov (United States)

    Våge, Selina; Thingstad, T. Frede

    2015-01-01

    Trophic interactions are highly complex and modern sequencing techniques reveal enormous biodiversity across multiple scales in marine microbial communities. Within the chemically and physically relatively homogeneous pelagic environment, this calls for an explanation beyond spatial and temporal heterogeneity. Based on observations of simple parasite-host and predator-prey interactions occurring at different trophic levels and levels of phylogenetic resolution, we present a theoretical perspective on this enormous biodiversity, discussing in particular self-similar aspects of pelagic microbial food web organization. Fractal methods have been used to describe a variety of natural phenomena, with studies of habitat structures being an application in ecology. In contrast to mathematical fractals where pattern generating rules are readily known, however, identifying mechanisms that lead to natural fractals is not straight-forward. Here we put forward the hypothesis that trophic interactions between pelagic microbes may be organized in a fractal-like manner, with the emergent network resembling the structure of the Sierpinski triangle. We discuss a mechanism that could be underlying the formation of repeated patterns at different trophic levels and discuss how this may help understand characteristic biomass size-spectra that hint at scale-invariant properties of the pelagic environment. If the idea of simple underlying principles leading to a fractal-like organization of the pelagic food web could be formalized, this would extend an ecologists mindset on how biological complexity could be accounted for. It may furthermore benefit ecosystem modeling by facilitating adequate model resolution across multiple scales. PMID:26648929

  10. Ecological theory in practice: illustrations from a community-based intervention to promote the health of recent mothers.

    Science.gov (United States)

    Hawe, Penelope; Riley, Therese

    2005-09-01

    We present a qualitative case study where we used four principles of ecological theory from community psychology as a template to assess the dynamics about how a preventive community intervention was transacted in eight communities in Victoria, Australia. The principles were cycling of resources, interdependence, adaptation, and succession. Ecological thinking focuses on key resources in communities. That is, the people, events, and settings that are the foundations of thinking about communities as systems. The data set consists of field diaries kept by and serial interviews with nine community development workers over a 2-year period. We found that the analysis highlighted a process-oriented way of representing the intervention, one that sees beyond the intervention's technical components (or packaged elements) to the complexities of the cultural and political change processes occurring beneath. The value of this is the attention focussed on likely project sustainability.

  11. Homeostasis of Complementary Pair Theory: Ecological Comparisons in Diverse Universal Design for Learning Environments

    Science.gov (United States)

    Ianneo, Brittany

    2014-01-01

    Accommodation~assimilation relations were theorized by Kelso and Engstrom (2006) as independent and dependent complementary pairs. This study defined relationships between organisms that experienced complementary interactions of accommodation~assimilation in diverse ecologies designed with universal design for learning environments (UDLE) compared…

  12. Species abundance distributions : moving beyond single prediction theories to integration within an ecological framework

    NARCIS (Netherlands)

    McGill, Brian J.; Etienne, Rampal S.; Gray, John S.; Alonso, David; Anderson, Marti J.; Benecha, Habtamu Kassa; Dornelas, Maria; Enquist, Brian J.; Green, Jessica L.; He, Fangliang; Hurlbert, Allen H.; Magurran, Anne E.; Marquet, Pablo A.; Maurer, Brian A.; Ostling, Annette; Soykan, Candan U.; Ugland, Karl I.; White, Ethan P.

    2007-01-01

    Species abundance distributions (SADs) follow one of ecology's oldest and most universal laws - every community shows a hollow curve or hyperbolic shape on a histogram with many rare species and just a few common species. Here, we review theoretical, empirical and statistical developments in the

  13. Species abundance distributions: moving beyond single prediction theories to integration within an ecological framework

    NARCIS (Netherlands)

    McGill, B.J.; Etienne, R.S.; Gray, J.S.; Alonso, D.; Anderson, M.J.; Benecha, H.K.

    2007-01-01

    Species abundance distributions (SADs) follow one of ecology's oldest and most universal laws ¿ every community shows a hollow curve or hyperbolic shape on a histogram with many rare species and just a few common species. Here, we review theoretical, empirical and statistical developments in the

  14. Environmental Education for Social-Ecological System Resilience: A Perspective from Activity Theory

    Science.gov (United States)

    Krasny, Marianne E.; Roth, Wolff-Michael

    2010-01-01

    In this paper we attempt to integrate environmental education, with a focus on building capacity at the level of the individual, with frameworks for resilience, with a focus on adaptive capacity at the level of the social-ecological system. Whereas previous work has focused on enhancing system-level capacity through building adaptive capacity in…

  15. Evolution Theory Teaching and Learning: What Conclusions Can We Get from Comparisons of Teachers' and Students' Conceptual Ecologies in Greece and Turkey?

    Science.gov (United States)

    Athanasiou, Kyriacos; Papadopoulou, Penelope

    2015-01-01

    In this study, we make an effort to compare studies that explore the factors related to acceptance of evolutionary theory among Greek and Turkish students-future teachers, using conceptual ecology for biological evolution as the theoretical framework. We aimed to look into the acceptance and the understanding of evolutionary theory and also to…

  16. Simple unification

    International Nuclear Information System (INIS)

    Ponce, W.A.; Zepeda, A.

    1987-08-01

    We present the results obtained from our systematic search of a simple Lie group that unifies weak and electromagnetic interactions in a single truly unified theory. We work with fractionally charged quarks, and allow for particles and antiparticles to belong to the same irreducible representation. We found that models based on SU(6), SU(7), SU(8) and SU(10) are viable candidates for simple unification. (author). 23 refs

  17. Reporting Sexual Victimization During Incarceration: Using Ecological Theory as a Framework to Inform and Guide Future Research.

    Science.gov (United States)

    Kubiak, Sheryl Pimlott; Brenner, Hannah; Bybee, Deborah; Campbell, Rebecca; Fedock, Gina

    2016-03-08

    The U.S. Department of Justice estimates that between 149,200 and 209,400 incidents of sexual victimization occur annually in prisons and jails. However, very few individuals experiencing sexual victimization during incarceration report these incidents to correctional authorities. Federal-level policy recommendations derived from the Prison Rape Elimination Act suggest mechanisms for improving reporting as well as standards for the prevention, investigation, and prosecution of prison-based sexual victimization. Despite these policy recommendations, sexual assault persists in prisons and jails, with only 8% of prisoners who experience sexual assault reporting their victimization. This review focuses on gaps in the existing research about what factors influence whether adult victims in incarcerated systems will report that they have been sexually assaulted. Using ecological theory to guide this review, various levels of social ecology are incorporated, illuminating a variety of factors influencing the reporting of sexual victimization during incarceration. These factors include the role of individual-level behavior, assault characteristics, the unique aspects and processes of the prison system, and the social stigma that surrounds individuals involved in the criminal/legal system. This review concludes with recommendations for future research, policy, and practice, informed by an ecological conceptualization of reporting. © The Author(s) 2016.

  18. External wall structure of green rural houses in Daqing, China, based on life cycle and ecological footprint theories

    Directory of Open Access Journals (Sweden)

    Hong Jin

    2015-09-01

    Full Text Available Daqing is situated in one of the severely cold regions of China. The living environment in this region is extremely poor because of the harsh climate and the backward economy. The external wall is an important component of the external envelope of buildings, and it greatly contributes to the indoor thermal environment. By taking the external wall as the research object, this study summarizes the characteristics of the external wall structure and analyzes the common materials used in existing rural residences. Specifically, we combine life cycle theory and ecological footprint (EF theory and introduce the green external wall structure, as well as its application in practice, in accordance with the local ecosystem. Results show that anecological residence offers a better environment and greater economic benefits than a traditional residence. The annual energy consumption, CO2 consumption, and EF of the ecological residence in this study are lower than those of the traditional residence by 69.61%, 17.5 t, and 99.47%, respectively.

  19. Nurse plant theory and its application in ecological restoration in lower subtropics of China

    Institute of Scientific and Technical Information of China (English)

    Hai Ren; Long Yang; Nan Liu

    2008-01-01

    Nurse plants are those that facilitate the growth and development of other plant species (target species) beneath their canopy because they offer benign microhabitats that are more favorable for seed germination and/or seedling recruitment than their surrounding envi-ronment. Nurse plants have been mainly used to restore vegetation in arid and sub-arid zones in recent years. Based on summarizing the definition of nurse plant and target plant, we review the nursing effect mechanisms, ecological factors that influence nursing effect, relationships between nurse plant and ecological restoration. This review also brings forward possible pairs of nurse and target species at lower subtropical areas. Furthermore, we provide the potential tendency in nurse plant research and application.

  20. Trees, fires and elephants: applying ecological theory to science-society issues in southern Africa

    CSIR Research Space (South Africa)

    Scholes, B

    2006-02-01

    Full Text Available such as satellites and flux towers have allowed the researchers to construct, for the first time, relatively simple predictive models. These models have, in turn, allowed new light to be cast on several important problems. The researchers were, for example, able...

  1. Ecological modernisation theory and the changing dynamics of the European automotive industry

    DEFF Research Database (Denmark)

    Smink, Carla Kornelia; van Koppen, C.S.A.; Spaargaren, Gert

    2003-01-01

    between technology and policy. We argue that some technological developments in handling end-of-life vehicles trigger policy questions. But also the other way around: some policy styles favour some development paths of end-of-life vehicle technologies and foreclose others. By this combined treatment...... of technological and political issues, we hope to contribute to the discussion on the overall organisation of the ELV-dimension of car chains in the future. We have chosen to deepen our understanding of the basic characteristics of the ecological modernisation process in car chains by looking in some detail...

  2. Health is Power: an ecological, theory-based health intervention for women of color.

    Science.gov (United States)

    Lee, Rebecca E; Medina, Ashley V; Mama, Scherezade K; Reese-Smith, Jacqueline Y; O'Connor, Daniel P; Brosnan, Marcella; Cubbin, Catherine; McMillan, Tracy; Estabrooks, Paul A

    2011-11-01

    Physical inactivity and poor dietary habits plague Americans as health challenges, with women of color most vulnerable to their detrimental effects. Individually focused interventions have not demonstrated lasting success, possibly due to the lack of focus on sustainable social and physical environment factors. This manuscript describes the rationale, design and methodology of Health Is Power (HIP), a transcultural, community based, randomized controlled trial that investigated the effectiveness of a group cohesion intervention to increase physical activity and improve dietary habits in African American and Hispanic or Latina women in Houston and Austin, Texas. The intervention development was guided by group dynamics principles anchored within an ecologic model. Women participated in three health assessments and a six month face to face intervention that included evidence-based behavioral methods - integrated into strategies to promote group cohesion - framed to account for environmental factors contributing to health disparities. Women participated in team building activities, environmental mapping exercises, and supervised walks or taste tests. Neighborhood contextual and environmental measures are described to test ecologic factors that may contribute to behavioral maintenance. Theoretically guided interventions that account for multiple levels of influence in behavior initiation and maintenance stand to improve health outcomes in vulnerable populations. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Health Is Power: an Ecological Theory-based Health Intervention for Women of Color

    Science.gov (United States)

    Lee, Rebecca E.; Medina, Ashley V.; Mama, Scherezade K.; Reese-Smith, Jacqueline Y.; O’Connor, Daniel P.; Brosnan, Marcella; Cubbin, Catherine; McMillan, Tracy; Estabrooks, Paul A.

    2011-01-01

    Objective Physical inactivity and poor dietary habits plague Americans as health challenges, with women of color most vulnerable to their detrimental effects. Individually focused interventions have not demonstrated lasting success, possibly due to the lack of focus on sustainable social and physical environment factors. This manuscript describes the rationale, design and methodology of Health Is Power (HIP), a transcultural, community based, randomized controlled trial that investigated the effectiveness of a group cohesion intervention to increase physical activity and improve dietary habits in African American and Hispanic or Latina women in Houston and Austin, Texas. Methods The intervention development was guided by group dynamics principles anchored within an ecologic model. Results Women participated in three health assessments and a six month face to face intervention that included evidence-based behavioral methods—integrated into strategies to promote group cohesion—framed to account for environmental factors contributing to health disparities. Women participated in team building activities, environmental mapping exercises, and supervised walks or taste tests. Conclusions Neighborhood contextual and environmental measures are described to test ecologic factors that may contribute to behavioral maintenance. Theoretically guided interventions that account for multiple levels of influence in behavior initiation and maintenance stand to improve health outcomes in vulnerable populations. PMID:21782975

  4. The proposition of a general version of the theory of planned behavior: Predicting ecological behavior

    NARCIS (Netherlands)

    Kaiser, F.G.; Gutscher, H.

    2003-01-01

    The present paper explores whether the theory of planned behavior (TPB) must abandon the notion that perceived behavioral control (PBC) has a direct influence on behavior. In a cross-sectional survey of 895 Swiss residents, our hypothesis was tested by means of structural equation models. Applied

  5. Cultural-Ecological Theory of Academic Disengagement Used to Explain a Story of Race, Culture and Education.

    Science.gov (United States)

    Ogunyemi, Boluwaji

    2017-01-01

    Students of African ancestry often share an experience of being a racialized minority in the context of the educational institution. Late Professor of Anthropology John Ogbu's Cultural-ecological Theory of Academic Disengagement is employed to describe the negative responses encountered by peers in the name of academic achievement. The late Nigerian-American anthropologist John Ogbu described that it is often socially disadvantageous for black youth to prosper academically in formal education. Black students are often seen as betraying their cultural identities by aspiring to academic success and scholastic achievement and are met with repugnance by black peers. The notion of "acting white" is unnecessary, impertinent should be abandoned outright as achievement should have no color. Copyright © 2017 National Medical Association. Published by Elsevier Inc. All rights reserved.

  6. Watching the Evolution of the American Family? Amazon's Transparent, Ecological Systems Theory, and the Changing Dynamics of Public Opinion.

    Science.gov (United States)

    Becker, Amy B; Todd, Maureen E

    2018-01-01

    Using Bronfenbrenner's (1979) ecological systems theory as an organizing framework, the research closely examines the text of the Amazon Studios hit show Transparent and, by extension, the evolution of public opinion toward transgender individuals. By examining the Pfefferman family in detail and their related microsystem and macrosystem, we are able to closely unpack the transition of Jeffrey Tambor's character from Mort to Maura and the show's connections with broader developments in the Los Angeles LGBT community and the Jewish diaspora in postwar and contemporary Los Angeles. In addition, by focusing on the influence of the chronosystem, we are able to examine how both opinions toward Maura and public opinion toward transgender issues more generally have evolved within the family system and the larger American community over time.

  7. Anisakis simplex complex: ecological significance of recombinant genotypes in an allopatric area of the Adriatic Sea inferred by genome-derived simple sequence repeats.

    Science.gov (United States)

    Mladineo, Ivona; Trumbić, Željka; Radonić, Ivana; Vrbatović, Anamarija; Hrabar, Jerko; Bušelić, Ivana

    2017-03-01

    The genus Anisakis includes nine species which, due to close morphological resemblance even in the adult stage, have previously caused many issues in their correct identification. Recently observed interspecific hybridisation in sympatric areas of two closely related species, Anisakis simplex sensu stricto (s.s.) and Anisakis pegreffii, has raised concerns whether a F1 hybrid generation is capable of overriding the breeding barrier, potentially giving rise to more resistant/pathogenic strains infecting humans. To assess the ecological significance of anisakid genotypes in the Adriatic Sea, an allopatric area for the two above-mentioned species, we analysed data from PCR-RFLP genotyping of the ITS region and the sequence of the cytochrome oxidase 2 (cox2) mtDNA locus to discern the parental genotype and maternal haplotype of the individuals. Furthermore, using in silico genome-wide screening of the A. simplex database for polymorphic simple sequence repeats or microsatellites in non-coding regions, we randomly selected potentially informative loci that were tested and optimised for multiplex PCR. The first panel of microsatellites developed for Anisakis was shown to be highly polymorphic, sensitive and amplified in both A. simplex s.s. and A. pegreffii. It was used to inspect genetic differentiation of individuals showing mito-nuclear mosaicism which is characteristic for both species. The observed low level of intergroup heterozygosity suggests that existing mosaicism is likely a retention of an ancestral polymorphism rather than a recent recombination event. This is also supported by allopatry of pure A. simplex s.s. and A. pegreffii in the geographical area under study. Copyright © 2017 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

  8. Psychological Trait Resilience Within Ecological Systems Theory: The Resilient Systems Scales.

    Science.gov (United States)

    Maltby, John; Day, Liz; Flowe, Heather D; Vostanis, Panos; Chivers, Sally

    2017-07-14

    This project describes the development of the Resilient Systems Scales, created to address conceptual and methodological ambiguities in assessing the ecological systems model of resilience. Across a number of samples (total N = 986), our findings suggest that the Resilient Systems Scales show equivalence to a previously reported assessment (Maltby, Day, & Hall, 2015 ) in demonstrating the same factor structure, adequate intercorrelation between the 2 measures of resilience, and equivalent associations with personality and well-being. The findings also suggest that the Resilient Systems Scales demonstrate adequate test-retest reliability, compare well with other extant measures of resilience in predicting well-being, and map, to varying degrees, onto positive expression of several cognitive, social, and emotional traits. The findings suggest that the new measure can be used alongside existing measures of resilience, or singly, to assess positive life outcomes within psychology research.

  9. Testing Ecological Theories of Offender Spatial Decision Making Using a Discrete Choice Model

    Science.gov (United States)

    Summers, Lucia

    2015-01-01

    Research demonstrates that crime is spatially concentrated. However, most research relies on information about where crimes occur, without reference to where offenders reside. This study examines how the characteristics of neighborhoods and their proximity to offender home locations affect offender spatial decision making. Using a discrete choice model and data for detected incidents of theft from vehicles (TFV), we test predictions from two theoretical perspectives—crime pattern and social disorganization theories. We demonstrate that offenders favor areas that are low in social cohesion and closer to their home, or other age-related activity nodes. For adult offenders, choices also appear to be influenced by how accessible a neighborhood is via the street network. The implications for criminological theory and crime prevention are discussed. PMID:25866412

  10. Testing Ecological Theories of Offender Spatial Decision Making Using a Discrete Choice Model.

    Science.gov (United States)

    Johnson, Shane D; Summers, Lucia

    2015-04-01

    Research demonstrates that crime is spatially concentrated. However, most research relies on information about where crimes occur, without reference to where offenders reside. This study examines how the characteristics of neighborhoods and their proximity to offender home locations affect offender spatial decision making. Using a discrete choice model and data for detected incidents of theft from vehicles (TFV) , we test predictions from two theoretical perspectives-crime pattern and social disorganization theories. We demonstrate that offenders favor areas that are low in social cohesion and closer to their home, or other age-related activity nodes. For adult offenders, choices also appear to be influenced by how accessible a neighborhood is via the street network. The implications for criminological theory and crime prevention are discussed.

  11. Urban ecology in a developing world: why advanced socioecological theory needs Africa

    OpenAIRE

    McHale, Melissa R; Bunn, David N; Pickett, Steward TA; Twine, Wayne

    2013-01-01

    Socioecological theory, developed through the study of urban environments, has recently led to a proliferation of research focusing on comparative analyses of cities. This research emphasis has been concentrated in the more developed countries of the Northern Hemisphere (often referred to as the “Global North”), yet urbanization is now occurring mostly in the developing world, with the fastest rates of growth in sub-Saharan Africa. Countries like South Africa are experiencing a variety of lan...

  12. Testing the Metabolic Theory of Ecology with marine bacteria: Different temperature sensitivity of major phylogenetic groups during the spring phytoplankton bloom

    KAUST Repository

    Arandia-Gorostidi, Nestor; Huete-Stauffer, Tamara Megan; Alonso-Sá ez, Laura; Moran, Xose Anxelu G.

    2017-01-01

    in general lower than 0.65 eV, the value predicted by the Metabolic Theory of Ecology (MTE). Contrary to MTE predictions, carrying capacity tended to increase with warming for all bacterial groups. Our analysis confirms that resource availability is key when

  13. Workshop on Control Theory Applied to Renewable Resource Management and Ecology

    CERN Document Server

    Skowronski, Janislaw

    1981-01-01

    As society becomes stressed by economic and population pressures, in turn, nature's renewable resources become stressed by harvesting pressures. For our own survival and euphoria, it is paramount that such resources remain as their name implies and not be driven to extinction through short term programs of over exploitation. Consideration of the harvesting of renewable resources leads to a simple question that was the theme of the workshop and is the focus of these proceedings: SUPPoRe you are assigned the role of manager for a specific renewable resource eco­ system. How would you decide on harvesting policies so that the system can be exploited economically yet at the same time maintain the integrity of the system? This, of course, is a loaded question. First of all, it is not clear that there is ever anyone single decision maker who is able to set the rules for all of the harvesters in an exploited ecosystem. The political process is complicated and to some extent unpredictable. This aspect of the questio...

  14. The Measurement and Role of Ecological Resilience Systems Theory Across Domain-Specific Outcomes: The Domain-Specific Resilient Systems Scales.

    Science.gov (United States)

    Maltby, John; Day, Liz; Hall, Sophie S; Chivers, Sally

    2017-10-01

    Research suggests that trait resilience may be best understood within an ecological resilient systems theory, comprising engineering, ecological, and adaptive capacity resilience. However, there is no evidence as to how this theory translates to specific life domains. Data from two samples (the United States, n = 1,278; the United Kingdom, n = 211) facilitated five studies that introduce the Domain-Specific Resilient Systems Scales for assessing ecological resilient systems theory within work, health, marriage, friendships, and education. The Domain-Specific Resilient Systems Scales are found to predict unique variance in job satisfaction, lower job burnout, quality-of-life following illness, marriage commitment, and educational engagement, while controlling for factors including sex, age, personality, cognitive ability, and trait resilience. The findings also suggest a distinction between the three resilience dimensions in terms of the types of systems to which they contribute. Engineering resilience may contribute most to life domains where an established system needs to be maintained, for example, one's health. Ecological resilience may contribute most to life domains where the system needs sustainability in terms of present and future goal orientation, for example, one's work. Adaptive Capacity may contribute most to life domains where the system needs to be retained, preventing it from reaching a crisis state, for example, work burnout.

  15. Örgütsel Ekoloji Kuramından Stratejik Yönetim Anlayışına = From the Organizational Ecology Theory to Strategic Management Approach

    Directory of Open Access Journals (Sweden)

    Adnan KALKAN

    2011-01-01

    Full Text Available In this study, it is aimed to point out the direction of change in the organizational ecology theory, which is one of the management approaches today. When it was promoted, this theory provided a way to clarify the harmony between the organizational structures and the environment.According to the organizational ecology theory, business organizations act as living organisms in that they undergo a natural selection in which some die out while others evolve and survive. In this theoretical study, the relationships of organizations with their environment in their development was tried to be explained within the framework of the organizational ecology theory and the strategic management approach.

  16. Simple Closed-Form Expression for Penning Reaction Rate Coefficients for Cold Molecular Collisions by Non-Hermitian Time-Independent Adiabatic Scattering Theory.

    Science.gov (United States)

    Pawlak, Mariusz; Ben-Asher, Anael; Moiseyev, Nimrod

    2018-01-09

    We present a simple expression and its derivation for reaction rate coefficients for cold anisotropic collision experiments based on adiabatic variational theory and time-independent non-Hermitian scattering theory. We demonstrate that only the eigenenergies of the resulting one-dimensional Schrödinger equation for different complex adiabats are required. The expression is applied to calculate the Penning ionization rate coefficients of an excited metastable helium atom with molecular hydrogen in an energy range spanning from hundreds of kelvins down to the millikelvin regime. Except for trivial quantities like the masses of the nuclei and the bond length of the diatomic molecule participating in the collision, one needs as input data only the complex potential energy surface (CPES). In calculations, we used recently obtained ab initio CPES by D. Bhattacharya et al. ( J. Chem. Theory Comput. 2017 , 13 , 1682 - 1690 ) without fitting parameters. The results show good accord with current measurements ( Nat. Phys. 2017 , 13 , 35 - 38 ).

  17. Selection of important ecological source patches base on Green Infrastructure theory: A case study of Wuhan city

    Science.gov (United States)

    Ke, Yuanyuan; Yu, Yan; Tong, Yan

    2018-01-01

    Selecting urban ecological patches is of great significance for constructing urban green infrastructure network, protecting urban biodiversity and ecological environment. With the support of GIS technology, a criterion for selecting sources of patches was developed according to existing planning. Then ecological source patches of terrestrial organism, aquatic and amphibious organism were selected in Wuhan city. To increase the connectivity of the ecological patches and achieve greater ecological protection benefits, the green infrastructure networks in Wuhan city were constructed with the minimum path analysis method. Finally, the characteristics of ecological source patches were analyzed with landscape metrics, and ecological protection importance degree of ecological source patches were evaluated comprehensively. The results showed that there were 23 important ecological source patches in Wuhan city, among which Sushan Temple Forest Patch, Lu Lake and Shangshe Lake Wetland Patch were the most important in all kinds of patches for ecological protection. This study can provide a scientific basis for the preservation of urban ecological space, the delineation of natural conservation areas and the protection of biological diversity.

  18. Perspective on "Statistical mechanical theory of irreversible processes. I. General theory and simple applications to magnetic and conduction problems."Kubo R J Phys Soc Jpn 12: 570

    NARCIS (Netherlands)

    Frenkel, D.

    2000-01-01

    Kubo's paper on linear-response theory provided a unified language to describe a wide variety of transport phenomena, both quantum and classical, in a suitable "microscopic" language. The paper has been crucial for subsequent developments in numerical simulation.

  19. Uncovering stability mechanisms in microbial ecosystems - combining microcosm experiments, computational modelling and ecological theory in a multidisciplinary approach

    Science.gov (United States)

    Worrich, Anja; König, Sara; Banitz, Thomas; Centler, Florian; Frank, Karin; Kästner, Matthias; Miltner, Anja; Thullner, Martin; Wick, Lukas

    2015-04-01

    Although bacterial degraders in soil are commonly exposed to fluctuating environmental conditions, the functional performance of the biodegradation processes can often be maintained by resistance and resilience mechanisms. However, there is still a gap in the mechanistic understanding of key factors contributing to the stability of such an ecosystem service. Therefore we developed an integrated approach combining microcosm experiments, simulation models and ecological theory to directly make use of the strengths of these disciplines. In a continuous interplay process, data, hypotheses, and central questions are exchanged between disciplines to initiate new experiments and models to ultimately identify buffer mechanisms and factors providing functional stability. We focus on drying and rewetting-cycles in soil ecosystems, which are a major abiotic driver for bacterial activity. Functional recovery of the system was found to depend on different spatial processes in the computational model. In particular, bacterial motility is a prerequisite for biodegradation if either bacteria or substrate are heterogeneously distributed. Hence, laboratory experiments focussing on bacterial dispersal processes were conducted and confirmed this finding also for functional resistance. Obtained results will be incorporated into the model in the next step. Overall, the combination of computational modelling and laboratory experiments identified spatial processes as the main driving force for functional stability in the considered system, and has proved a powerful methodological approach.

  20. Information Ecology

    DEFF Research Database (Denmark)

    Christiansen, Ellen Tove

    2006-01-01

    in the 1960ties, and chosen here because it integrates cultural and psychological trajectories in a theory of living settings. The pedagogical-didactical paradigm comprises three distinct information ecologies, named after their intended outcome: the problem-setting, the exploration-setting, and the fit...

  1. Strategic Ecological Network Competition in Emerging Markets: Theory and Case Analysis of A GPS Vehicle Navigation Firm

    Institute of Scientific and Technical Information of China (English)

    XIAO Lei; LI Shi-ming; ZHANG Jia-tong

    2006-01-01

    Using the case study methodology, firm's competition behavior in strategic network and strategic ecosystems are analyzed. With the ecology view, there is consistency between strategic network and strategic ecosystem. Enterprise should pursue for suitable ecological niche to hold a strategic competitive power.

  2. Design of arbitrarily homogeneous permanent magnet systems for NMR and MRI: theory and experimental developments of a simple portable magnet.

    Science.gov (United States)

    Hugon, Cedric; D'Amico, Francesca; Aubert, Guy; Sakellariou, Dimitris

    2010-07-01

    Starting from general results of magnetostatics, we give fundamental considerations on the design and characterization of permanent magnets for NMR based on harmonic analysis and symmetry. We then propose a simple geometry that takes advantage of some of these considerations and discuss the practical aspects of the assembly of a real magnet based on this geometry, involving the characterization of its elements, the optimization of the layout and the correction of residual inhomogeneities due to material and geometry imperfections. We report with this low-cost, light-weight magnet (100 euros and 1.8 kg including the aluminum frame) a field of 120 mT (5.1 MHz proton) with a 10 ppm natural homogeneity over a sphere of 1.5 mm in diameter. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  3. A Computational Mechatronics Approach for the Analysis, Synthesis and Design of a Simple Active Biped Robot: Theory and Experiments

    Directory of Open Access Journals (Sweden)

    L.-I. Lugo-Villeda

    2006-01-01

    Full Text Available Biped walking is a quite complex process that has been mastered only by human beings. Transferring this skill to a robot requires implementing advanced techniques in every aspect. To this end, a computational mechatronics platform was integrated to run the scheme for the analysis, synthesis and design to achieve planar biped walking. The result is an advanced computational tool that integrates advanced modeling and control as well as path planning techniques along with hardware-in-the-loop for perhaps the simplest biped robot. An experimental underactuated three-degree-of-freedom (two active and one passive active biped robot yields encouraging results; that is, achieving biped walking with this simple device requires adding a telescopic support leg. Considering a more complete dynamic model to take into account frictional and contact forces.

  4. Top management team composition and organizational ecology : A nested hierarchical selection theory of team reproduction and organizational diversity

    NARCIS (Netherlands)

    Boone, Christophe; Wezel, Filippo C.; van Witteloostuijn, Arjen; Baum, JAC; Dobrev, SD; VanWitteloostuijn, A

    2006-01-01

    The "upper echelon" literature has mainly produced static empirical studies on the impact of top management team composition on organizational outcomes, ignoring the dynamics of industrial demography. Organizational ecology explicitly studied the dynamics of organizational diversity at the

  5. A simple model of ultrasound propagation in a cavitating liquid. Part I: Theory, nonlinear attenuation and traveling wave generation.

    Science.gov (United States)

    Louisnard, O

    2012-01-01

    The bubbles involved in sonochemistry and other applications of cavitation oscillate inertially. A correct estimation of the wave attenuation in such bubbly media requires a realistic estimation of the power dissipated by the oscillation of each bubble, by thermal diffusion in the gas and viscous friction in the liquid. Both quantities and calculated numerically for a single inertial bubble driven at 20 kHz, and are found to be several orders of magnitude larger than the linear prediction. Viscous dissipation is found to be the predominant cause of energy loss for bubbles small enough. Then, the classical nonlinear Caflish equations describing the propagation of acoustic waves in a bubbly liquid are recast and simplified conveniently. The main harmonic part of the sound field is found to fulfill a nonlinear Helmholtz equation, where the imaginary part of the squared wave number is directly correlated with the energy lost by a single bubble. For low acoustic driving, linear theory is recovered, but for larger drivings, namely above the Blake threshold, the attenuation coefficient is found to be more than 3 orders of magnitude larger then the linear prediction. A huge attenuation of the wave is thus expected in regions where inertial bubbles are present, which is confirmed by numerical simulations of the nonlinear Helmholtz equation in a 1D standing wave configuration. The expected strong attenuation is not only observed but furthermore, the examination of the phase between the pressure field and its gradient clearly demonstrates that a traveling wave appears in the medium. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. A simple scaling law for the equation of state and the radial distribution functions calculated by density-functional theory molecular dynamics

    Science.gov (United States)

    Danel, J.-F.; Kazandjian, L.

    2018-06-01

    It is shown that the equation of state (EOS) and the radial distribution functions obtained by density-functional theory molecular dynamics (DFT-MD) obey a simple scaling law. At given temperature, the thermodynamic properties and the radial distribution functions given by a DFT-MD simulation remain unchanged if the mole fractions of nuclei of given charge and the average volume per atom remain unchanged. A practical interest of this scaling law is to obtain an EOS table for a fluid from that already obtained for another fluid if it has the right characteristics. Another practical interest of this result is that an asymmetric mixture made up of light and heavy atoms requiring very different time steps can be replaced by a mixture of atoms of equal mass, which facilitates the exploration of the configuration space in a DFT-MD simulation. The scaling law is illustrated by numerical results.

  7. Competitive Traits Are More Important than Stress-Tolerance Traits in a Cadmium-Contaminated Rhizosphere: A Role for Trait Theory in Microbial Ecology.

    Science.gov (United States)

    Wood, Jennifer L; Tang, Caixian; Franks, Ashley E

    2018-01-01

    Understanding how biotic and abiotic factors govern the assembly of rhizosphere-microbial communities is a long-standing goal in microbial ecology. In phytoremediation research, where plants are used to remediate heavy metal-contaminated soils, a deeper understanding of rhizosphere-microbial ecology is needed to fully exploit the potential of microbial-assisted phytoremediation. This study investigated whether Grime's competitor/stress-tolerator/ruderal (CSR) theory could be used to describe the impact of cadmium (Cd) and the presence of a Cd-accumulating plant, Carpobrotus rossii (Haw.) Schwantes, on the assembly of soil-bacterial communities using Illumina 16S rRNA profiling and the predictive metagenomic-profiling program, PICRUSt. Using predictions based on CSR theory, we hypothesized that Cd and the presence of a rhizosphere would affect community assembly. We predicted that the additional resource availability in the rhizosphere would enrich for competitive life strategists, while the presence of Cd would select for stress-tolerators. Traits identified as competitive followed CSR predictions, discriminating between rhizosphere and bulk-soil communities whilst stress-tolerance traits increased with Cd dose, but only in bulk-soil communities. These findings suggest that a bacterium's competitive attributes are critical to its ability to occupy and proliferate in a Cd-contaminated rhizosphere. Ruderal traits, which relate to community re-colonization potential, were synergistically decreased by the presence of the rhizosphere and Cd dose. Taken together this microcosm study suggests that the CSR theory is broadly applicable to microbial communities. Further work toward developing a simplified and robust strategy for microbial CSR classification will provide an ecologically meaningful framework to interpret community-level changes across a range of biomes.

  8. A simple and efficient dispersion correction to the Hartree-Fock theory (2): Incorporation of a geometrical correction for the basis set superposition error.

    Science.gov (United States)

    Yoshida, Tatsusada; Hayashi, Takahisa; Mashima, Akira; Chuman, Hiroshi

    2015-10-01

    One of the most challenging problems in computer-aided drug discovery is the accurate prediction of the binding energy between a ligand and a protein. For accurate estimation of net binding energy ΔEbind in the framework of the Hartree-Fock (HF) theory, it is necessary to estimate two additional energy terms; the dispersion interaction energy (Edisp) and the basis set superposition error (BSSE). We previously reported a simple and efficient dispersion correction, Edisp, to the Hartree-Fock theory (HF-Dtq). In the present study, an approximation procedure for estimating BSSE proposed by Kruse and Grimme, a geometrical counterpoise correction (gCP), was incorporated into HF-Dtq (HF-Dtq-gCP). The relative weights of the Edisp (Dtq) and BSSE (gCP) terms were determined to reproduce ΔEbind calculated with CCSD(T)/CBS or /aug-cc-pVTZ (HF-Dtq-gCP (scaled)). The performance of HF-Dtq-gCP (scaled) was compared with that of B3LYP-D3(BJ)-bCP (dispersion corrected B3LYP with the Boys and Bernadi counterpoise correction (bCP)), by taking ΔEbind (CCSD(T)-bCP) of small non-covalent complexes as 'a golden standard'. As a critical test, HF-Dtq-gCP (scaled)/6-31G(d) and B3LYP-D3(BJ)-bCP/6-31G(d) were applied to the complex model for HIV-1 protease and its potent inhibitor, KNI-10033. The present results demonstrate that HF-Dtq-gCP (scaled) is a useful and powerful remedy for accurately and promptly predicting ΔEbind between a ligand and a protein, albeit it is a simple correction procedure. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Towards a unified theory of cooperative breeding : The role of ecology and life history re-examined

    NARCIS (Netherlands)

    Pen, I.; Weissing, F.J.

    2000-01-01

    We present quantitative models that unify several adaptive hypotheses for the evolution of cooperative breeding in a single framework: the ecological constraints hypothesis, the life-history hypothesis and the benefits-of-philopatry hypothesis. Our goal is to explain interspecific variation in the

  10. Simple WZW currents

    International Nuclear Information System (INIS)

    Fuchs, J.

    1990-08-01

    A complete classification of simple currents of WZW theory is obtained. The proof is based on an analysis of the quantum dimensions of the primary fields. Simple currents are precisely the primaries with unit quantum dimension; for WZW theories explicit formulae for the quantum dimensions can be derived so that an identification of the fields with unit quantum dimension is possible. (author). 19 refs.; 2 tabs

  11. Using ecological theory to evaluate the effectiveness of an indigenous community intervention: A study of Sexual Assault Nurse Examiner (SANE) programs.

    Science.gov (United States)

    Campbell, Rebecca; Patterson, Debra; Fehler-Cabral, Giannina

    2010-12-01

    In recent years, there has been renewed interest among community psychologists in indigenous interventions, which are programs created by local practitioners (rather than researchers) already rooted in their communities. Indigenous interventions have strong ecological validity, but their effectiveness is often unknown because so few are rigorously evaluated. The goal of this project was to use Kelly and Trickett's ecological theory as a conceptual framework for evaluating an indigenous intervention and its mediating mechanisms of effectiveness. The focal intervention was a midwestern Sexual Assault Nurse Examiner (SANE) program, which provides post-assault medical care, crisis intervention, and medical forensic exams for sexual assault survivors. Prior studies of SANE programs have suggested that these interventions may help increase sexual assault prosecution rates. In this case example, we used a mixed methods design to determine if this program contributed to increased prosecution rates, and if so, why. Based on qualitative interviews with key stakeholders, we found substantial evidence for the Principle of Interdependence such that the SANE program strengthened the interconnections between the legal and medical systems, which contributed to increased prosecution. The intervention was effective in these outcomes because it promoted Cycling of Resources throughout the systems and fostered Adaptation of new roles for legal and medical personnel. Moving beyond this specific case example, this paper also examines cross-cutting advantages and struggles of using an ecological approach in the evaluation of indigenous community interventions.

  12. Measurement Method and Empirical Research on the Sustainable Development Capability of a Regional Industrial System Based on Ecological Niche Theory in China

    Directory of Open Access Journals (Sweden)

    Hang Yin

    2014-11-01

    Full Text Available From the analytical view of a recycling economy, the regional system achieves the goal of sustainable development through improving resource utilization efficiency, reducing energy consumption and ameliorating the quality of water and air. The regional economic system’s potential for sustainable development is significantly influenced by regional industrial operational efficiency, which measures the cost of ecology, environment, energy and resources accompanying the economic growth. It is vital for national and regional governments to accelerate harmonious development between products of industrial department, consumption of energy and pollutants discharged. Under the guidance of ecological niche theory and recycling economy theory, the theoretical analysis on efficient relations between regional industrial growth, energy consumption, resources utilization and environmental carrying capacity has been carried out from horizontal and vertical respects. Industrial operational efficiency and the sensitivity coefficient in response to the change of every input and output index can be calculated and critical factors, which restrict sustainable development capability, can be found out so that quantitative references could be provided for administrative decisions. As for the measurement method, a super efficiency mixed data envelopment analysis model, which wipes off self-limited condition and either contains both meeting cone characteristic indexes or not, has been established and applied. Statistics from 1993 to 2012 in China are collected to carry out empirical research. On the basis of further analysis, an adjustment strategy can be constituted to improve the capability for sustainable development.

  13. [Ecology and ecologies].

    Science.gov (United States)

    Valera, Luca

    2011-01-01

    Ecology (from the Greek words οιχοσ, "house" and λογια "study of") is the science of the "house", since it studies the environments where we live. There are three main ways of thinking about Ecology: Ecology as the study of interactions (between humans and the environment, between humans and living beings, between all living beings, etc.), Ecology as the statistical study of interactions, Ecology as a faith, or rather as a science that requires a metaphysical view. The history of Ecology shows us how this view was released by the label of "folk sense" to gain the epistemological status of science, a science that strives to be interdisciplinary. So, the aim of Ecology is to study, through a scientific methodology, the whole natural world, answering to very different questions, that arise from several fields (Economics, Biology, Sociology, Philosophy, etc.). The plurality of issues that Ecology has to face led, during the Twentieth-century, to branch off in several different "ecologies". As a result, each one of these new approaches chose as its own field a more limited and specific portion of reality.

  14. Between Design and Ecology

    DEFF Research Database (Denmark)

    Bjørn, Mona Chor

    such vegetation, based on concepts and theories in plant community ecology. If these communities are based on local forbs there is a continuum in anthropogenic intervention from designed and intensively maintained to semi-natural herbaceous vegetation. Results from a large field experiment show that, after three...... colonised by grasses and eventually woody species. This thesis adds useful basic knowledge in plant community ecology and species-specific growth, which are relevant to research and planning in landscape architecture and ecology....

  15. Simple machines

    CERN Document Server

    Graybill, George

    2007-01-01

    Just how simple are simple machines? With our ready-to-use resource, they are simple to teach and easy to learn! Chocked full of information and activities, we begin with a look at force, motion and work, and examples of simple machines in daily life are given. With this background, we move on to different kinds of simple machines including: Levers, Inclined Planes, Wedges, Screws, Pulleys, and Wheels and Axles. An exploration of some compound machines follows, such as the can opener. Our resource is a real time-saver as all the reading passages, student activities are provided. Presented in s

  16. Social Ecology of Asthma: Engaging Stakeholders in Integrating Health Behavior Theories and Practice-Based Evidence through Systems Mapping

    Science.gov (United States)

    Gillen, Emily M.; Hassmiller Lich, Kristen; Yeatts, Karin B.; Hernandez, Michelle L.; Smith, Timothy W.; Lewis, Megan A.

    2014-01-01

    This article describes a process for integrating health behavior and social science theories with practice-based insights using participatory systems thinking and diagramming methods largely inspired by system dynamics methods. This integration can help close the gap between research and practice in health education and health behavior by offering…

  17. Predicting who will major in a science discipline: Expectancy-value theory as part of an ecological model for studying academic communities

    Science.gov (United States)

    Sullins, Ellen S.; Hernandez, Delia; Fuller, Carol; Shiro Tashiro, Jay

    Research on factors that shape recruitment and retention in undergraduate science majors currently is highly fragmented and in need of an integrative research framework. Such a framework should incorporate analyses of the various levels of organization that characterize academic communities (i.e., the broad institutional level, the departmental level, and the student level), and should also provide ways to study the interactions occurring within and between these structural levels. We propose that academic communities are analogous to ecosystems, and that the research paradigms of modern community ecology can provide the necessary framework, as well as new and innovative approaches to a very complex area. This article also presents the results of a pilot study that demonstrates the promise of this approach at the student level. We administered a questionnaire based on expectancy-value theory to undergraduates enrolled in introductory biology courses. Itself an integrative approach, expectancy-value theory views achievement-related behavior as a joint function of the person's expectancy of success in the behavior and the subjective value placed on such success. Our results indicated: (a) significant gender differences in the underlying factor structures of expectations and values related to the discipline of biology, (b) expectancy-value factors significantly distinguished biology majors from nonmajors, and (c) expectancy-value factors significantly predicted students' intent to enroll in future biology courses. We explore the expectancy-value framework as an operationally integrative framework in our ecological model for studying academic communities, especially in the context of assessing the underrepresentation of women and minorities in the sciences. Future research directions as well as practical implications are also discussed.

  18. Dynamics in artifact ecologies

    DEFF Research Database (Denmark)

    Bødker, Susanne; Klokmose, Clemens Nylandsted

    2012-01-01

    We increasingly interact with multiple interactive artifacts with overlapping capabilities during our daily activities. It has previously been shown that the use of an interactive artifact cannot be understood in isolation, but artifacts must be understood as part of an artifact ecology, where...... artifacts influence the use of others. Understanding this interplay becomes more and more essential for interaction design as our artifact ecologies grow. This paper continues a recent discourse on artifact ecologies. Through interviews with iPhone users, we demonstrate that relationships between artifacts...... in artifact ecologies cannot be understood as static, instead they evolve dynamically over time. We provide activity theory-based concepts to explain these dynamics....

  19. Beyond positivist ecology: toward an integrated ecological ethics.

    Science.gov (United States)

    Norton, Bryan G

    2008-12-01

    A post-positivist understanding of ecological science and the call for an "ecological ethic" indicate the need for a radically new approach to evaluating environmental change. The positivist view of science cannot capture the essence of environmental sciences because the recent work of "reflexive" ecological modelers shows that this requires a reconceptualization of the way in which values and ecological models interact in scientific process. Reflexive modelers are ecological modelers who believe it is appropriate for ecologists to examine the motives for their choices in developing models; this self-reflexive approach opens the door to a new way of integrating values into public discourse and to a more comprehensive approach to evaluating ecological change. This reflexive building of ecological models is introduced through the transformative simile of Aldo Leopold, which shows that learning to "think like a mountain" involves a shift in both ecological modeling and in values and responsibility. An adequate, interdisciplinary approach to ecological valuation, requires a re-framing of the evaluation questions in entirely new ways, i.e., a review of the current status of interdisciplinary value theory with respect to ecological values reveals that neither of the widely accepted theories of environmental value-neither economic utilitarianism nor intrinsic value theory (environmental ethics)-provides a foundation for an ecologically sensitive evaluation process. Thus, a new, ecologically sensitive, and more comprehensive approach to evaluating ecological change would include an examination of the metaphors that motivate the models used to describe environmental change.

  20. Grasshopper Population Ecology: Catastrophe, Criticality, and Critique

    Directory of Open Access Journals (Sweden)

    Dale R. Lockwood

    2008-06-01

    Full Text Available Grasshopper population dynamics are an important part of the North American rangeland ecosystem and an important factor in the economies that derive from the rangeland. Outbreak dynamics have plagued management strategies in the rangeland, and attempts to find simple, linear and mechanistic solutions to both understanding and predicting the dynamics have proved fruitless. These efforts to ground theory in a correspondence with the "real" world, including whether the population dynamics are ultimately density dependent or density independent, have generated abundant heat but little light. We suggest that a pragmatic approach, in which theories are taken to be "tools" rather than competing claims of truth, has greater promise to move ecological research in a constructive direction. Two recent non-linear approaches exploiting the tools of complexity science provide insights relevant to explaining and forecasting population dynamics. Observation and data collection were used to structure models derived from catastrophe theory and self-organized criticality. These models indicate that nonlinear processes are important in the dynamics of the outbreaks. And the conceptual structures of these approaches provide clear, albeit constrained or contingent, implications for pest managers. We show that, although these two frameworks, catastrophe theory and self-organized criticality, are very different, the frequency distributions of time series from both systems result in power law relationships. Further, we show that a simple lattice-based model, similar to SOC but structured on the biology of the grasshoppers gives a spatial time series similar to data over a 50-year span and the frequency distribution is also a power law relationship. This demonstration exemplifies how a "both-and" rather than an "either-or" approach to ecological modeling, in which the useful elements of particular theories or conceptual structures are extracted, may provide a way forward

  1. Ecological extension of the theory of evolution by natural selection from a perspective of Western and Eastern holistic philosophy.

    Science.gov (United States)

    Nakajima, Toshiyuki

    2017-12-01

    Evolution by natural selection requires the following conditions: (1) a particular selective environment; (2) variation of traits in the population; (3) differential survival/reproduction among the types of organisms; and (4) heritable traits. However, the traditional (standard) model does not clearly explain how and why these conditions are generated or determined. What generates a selective environment? What generates new types? How does a certain type replace, or coexist with, others? In this paper, based on the holistic philosophy of Western and Eastern traditions, I focus on the ecosystem as a higher-level system and generator of conditions that induce the evolution of component populations; I also aim to identify the ecosystem processes that generate those conditions. In particular, I employ what I call the scientific principle of dependent-arising (SDA), which is tailored for scientific use and is based on Buddhism principle called "pratītya-samutpāda" in Sanskrit. The SDA principle asserts that there exists a higher-level system, or entity, which includes a focal process of a system as a part within it; this determines or generates the conditions required for the focal process to work in a particular way. I conclude that the ecosystem generates (1) selective environments for component species through ecosystem dynamics; (2) new genetic types through lateral gene transfer, hybridization, and symbiogenesis among the component species of the ecosystem; (3) mechanistic processes of replacement of an old type with a new one. The results of this study indicate that the ecological extension of the theoretical model of adaptive evolution is required for better understanding of adaptive evolution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. The potential of ecological theory for building an integrated framework to develop the public health contribution of health visiting.

    Science.gov (United States)

    Bryans, Alison; Cornish, Flora; McIntosh, Jean

    2009-11-01

    In line with recent UK and Scottish policy imperatives, there is increasing pressure for the health visiting service to assume an enhanced role in improving public health. Although health visiting has so far maintained its unique position as a primarily preventive service within the UK health service, its distinctive contribution now appears under threat. The continuing absence of a comprehensive and integrated conceptual basis for practice has a negative impact on the profession's ability to respond to current challenges. Establishing an integrative framework to conceptualise health visiting practice would enable more sensitive, focused and appropriate research, education and evaluation in relation to practice. Work in this area could thus usefully contribute to the future development of the service at a difficult time. Our paper aims to make such a contribution. In support of our conceptual aims, we draw on a study of health visiting practice undertaken within a large conurbation in central Scotland. The study used a mixed method, collaborative approach involving 12 audio-recorded and observed health visitor-client interactions, semi-structured interviews with the 12 HVs and 12 clients, examination of related documentation and workshops with the HV participants. We critically consider prevalent models of health visiting practice and describe the more integrative conceptual approach provided by Bronfenbrenner's ecological, 'person-in-context' framework. The paper subsequently explores relationships between this framework and understandings of need demonstrated by health visitors who participated in our study. Current policy emphasises the need to focus on public health and social inclusion in order to improve health. However, if this policy is to be translated into practice, we must develop a more adequate understanding of how practitioners work effectively with families and individuals in a sensitive and context-specific manner. Bronfenbrenner's framework appears

  3. Simple prostatectomy

    Science.gov (United States)

    ... Han M, Partin AW. Simple prostatectomy: open and robot-assisted laparoscopic approaches. In: Wein AJ, Kavoussi LR, ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

  4. What Do Ecological Paradigms Offer to Conservation?

    International Nuclear Information System (INIS)

    Ale, S.B.; Howe, H.F.; Ale, S.B.; Howe, H.F.

    2010-01-01

    Ecological theory provides applications to biodiversity management but often falls short of expectations. One possibility is that heuristic theories of a young science are too immature. Logistic growth predicts a carrying capacity, but fisheries managed with the Lotka-Volterra paradigm continue to collapse. A second issue is that general predictions may not be useful. The theory of island biogeography predicts species richness but does not predict community composition. A third possibility is that the theory itself may not have much to do with nature, or that empirical parameterization is too difficult to know. The meta population paradigm is relevant to conservation, but meta populations might not be common in nature. For instance, empirical parameterization within the meta population paradigm is usually infeasible. A challenge is to determine why ecology fails to match needs of managers sometimes but helps at other. Managers may expect too much of paradigmatic blueprints, while ecologists believe them too much. Those who implement biodiversity conservation plans need simple, pragmatic guidelines based on science. Is this possible. What is possible An eclectic review of theory and practice demonstrate the power and weaknesses of the ideas that guide conservation and attempt to identify reasons for prevailing disappointment.

  5. Copepod community growth rates in relation to body size, temperature, and food availability in the East China Sea: a test of metabolic theory of ecology

    Directory of Open Access Journals (Sweden)

    K. Y. Lin

    2013-03-01

    Full Text Available Zooplankton play an essential role in marine food webs, and understanding how community-level growth rates of zooplankton vary in the field is critical for predicting how marine ecosystem function may vary in the face of environmental changes. Here, we used the artificial cohort method to examine the effects of temperature, body size, and chlorophyll concentration (a proxy for food on weight-specific growth rates for copepod communities in the East China Sea. Specifically, we tested the hypothesis that copepod community growth rates can be described by the metabolic theory of ecology (MTE, linking spatio-temporal variation of copepod growth rate with temperature and their body size. Our results generally agree with predictions made by the MTE and demonstrate that weight-specific growth rates of copepod communities in our study area are positively related with temperature and negatively related to body size. However, the regression coefficients of body size do not approach the theoretical predictions. Furthermore, we find that the deviation from the MTE predictions may be partly attributed to the effect of food availability (which is not explicitly accounted for by the MTE. In addition, significant difference in the coefficients of temperature and body size exists among taxonomic groups. Our results suggest that considering the effects of food limitation and taxonomy is necessary to better understand copepod growth rates under in situ conditions, and such effects on the MTE-based predictions need further investigation.

  6. Testing the Metabolic Theory of Ecology with marine bacteria: Different temperature sensitivity of major phylogenetic groups during the spring phytoplankton bloom

    KAUST Repository

    Arandia-Gorostidi, Nestor

    2017-08-24

    Although temperature is a key driver of bacterioplankton metabolism, the effect of ocean warming on different bacterial phylogenetic groups remains unclear. Here, we conducted monthly short-term incubations with natural coastal bacterial communities over an annual cycle to test the effect of experimental temperature on the growth rates and carrying capacities of four phylogenetic groups: SAR11, Rhodobacteraceae, Gammaproteobacteria and Bacteroidetes. SAR11 was the most abundant group year-round as analysed by CARD-FISH, with maximum abundances in summer, while the other taxa peaked in spring. All groups, including SAR11, showed high temperature-sensitivity of growth rates and/or carrying capacities in spring, under phytoplankton bloom or post-bloom conditions. In that season, Rhodobacteraceae showed the strongest temperature response in growth rates, estimated here as activation energy (E, 1.43 eV), suggesting an advantage to outcompete other groups under warmer conditions. In summer E values were in general lower than 0.65 eV, the value predicted by the Metabolic Theory of Ecology (MTE). Contrary to MTE predictions, carrying capacity tended to increase with warming for all bacterial groups. Our analysis confirms that resource availability is key when addressing the temperature response of heterotrophic bacterioplankton. We further show that even under nutrient-sufficient conditions, warming differentially affected distinct bacterioplankton taxa. This article is protected by copyright. All rights reserved.

  7. Ecological Ethics

    International Nuclear Information System (INIS)

    Oughton, Deborah

    2013-01-01

    Deborah Oughton started with a view of the work in progress by the ICRP TG 94 on ethics, from the historical context and the principles-based ethics in RP, to continue with an overview of the ethical theories and with the main area of elaboration which concerns the common values, to conclude with considerations about the implementation in different area such as biomedicine, nuclear safety and workers, ecological aspects, and environmental health and society. By reading again the ICRP and IAEA publications on the ethical aspects in the protection of environment from the effects of ionizing radiation, the presentation covers the various and different cultures within the history of environmental ethics, the perception of Nature and the theories of environmental ethics, in particular by focusing on anthropocentrism, biocentrism and ecocentrism, as philosophical worldwide views, and on conservation, biodiversity, sustainability, environmental justice and human dignity, as primary principles of environmental protection. The influence of western Christianity, with a view of man dominating over every creeping thing on earth, and of the non-western ideas, the human perception of Nature has been analyzed and discussed to conclude that, in reality then, the anthropocentrism, biocentrism and ecocentrism, as reflected in many cultures and religions, they all support the need to protect the environment and to recognise and preserve the diversity. Three challenges were then discussed in the presentation: the ecosystem approach and ecological economics, for example in the case of Fukushima by asking what is the economic cost of marine contamination; the ecosystem changes with attention to what harms, as in the case of the environment in the contaminated areas around Chernobyl; and the environmental consequences of remediation, which can be considered a source of controversy for environmental ethics and policy

  8. Trade-offs between seed and leaf size (seed-phytomer-leaf theory): functional glue linking regenerative with life history strategies … and taxonomy with ecology?

    Science.gov (United States)

    Hodgson, John G; Santini, Bianca A; Montserrat Marti, Gabriel; Royo Pla, Ferran; Jones, Glynis; Bogaard, Amy; Charles, Mike; Font, Xavier; Ater, Mohammed; Taleb, Abdelkader; Poschlod, Peter; Hmimsa, Younes; Palmer, Carol; Wilson, Peter J; Band, Stuart R; Styring, Amy; Diffey, Charlotte; Green, Laura; Nitsch, Erika; Stroud, Elizabeth; Romo-Díez, Angel; de Torres Espuny, Lluis; Warham, Gemma

    2017-11-10

    While the 'worldwide leaf economics spectrum' (Wright IJ, Reich PB, Westoby M, et al. 2004. The worldwide leaf economics spectrum. Nature : 821-827) defines mineral nutrient relationships in plants, no unifying functional consensus links size attributes. Here, the focus is upon leaf size, a much-studied plant trait that scales positively with habitat quality and components of plant size. The objective is to show that this wide range of relationships is explicable in terms of a seed-phytomer-leaf (SPL) theoretical model defining leaf size in terms of trade-offs involving the size, growth rate and number of the building blocks (phytomers) of which the young shoot is constructed. Functional data for 2400+ species and English and Spanish vegetation surveys were used to explore interrelationships between leaf area, leaf width, canopy height, seed mass and leaf dry matter content (LDMC). Leaf area was a consistent function of canopy height, LDMC and seed mass. Additionally, size traits are partially uncoupled. First, broad laminas help confer competitive exclusion while morphologically large leaves can, through dissection, be functionally small. Secondly, leaf size scales positively with plant size but many of the largest-leaved species are of medium height with basally supported leaves. Thirdly, photosynthetic stems may represent a functionally viable alternative to 'small seeds + large leaves' in disturbed, fertile habitats and 'large seeds + small leaves' in infertile ones. Although key elements defining the juvenile growth phase remain unmeasured, our results broadly support SPL theory in that phytometer and leaf size are a product of the size of the initial shoot meristem (≅ seed mass) and the duration and quality of juvenile growth. These allometrically constrained traits combine to confer ecological specialization on individual species. Equally, they appear conservatively expressed within major taxa. Thus, 'evolutionary canalization' sensu Stebbins (Stebbins GL

  9. Complex adaptive systems ecology

    DEFF Research Database (Denmark)

    Sommerlund, Julie

    2003-01-01

    In the following, I will analyze two articles called Complex Adaptive Systems EcologyI & II (Molin & Molin, 1997 & 2000). The CASE-articles are some of the more quirkyarticles that have come out of the Molecular Microbial Ecology Group - a groupwhere I am currently making observational studies....... They are the result of acooperation between Søren Molin, professor in the group, and his brother, JanMolin, professor at Department of Organization and Industrial Sociology atCopenhagen Business School. The cooperation arises from the recognition that bothmicrobial ecology and sociology/organization theory works...

  10. Ecological aspects influencing the implementation of inclusive ...

    African Journals Online (AJOL)

    Keywords: Assessment and Support Strategy, barriers to learning, ecological model, identification, inclusive ..... impedes the management of these learners in the mainstream schools. ..... An ecological systems theory perspective on youth.

  11. Root-root interactions: extending our perspective to be more inclusive of the range of theories in ecology and agriculture using in-vivo analyses.

    Science.gov (United States)

    Faget, Marc; Nagel, Kerstin A; Walter, Achim; Herrera, Juan M; Jahnke, Siegfried; Schurr, Ulrich; Temperton, Vicky M

    2013-07-01

    There is a large body of literature on competitive interactions among plants, but many studies have only focused on above-ground interactions and little is known about root-root dynamics between interacting plants. The perspective on possible mechanisms that explain the outcome of root-root interactions has recently been extended to include non-resource-driven mechanisms (as well as resource-driven mechanisms) of root competition and positive interactions such as facilitation. These approaches have often suffered from being static, partly due to the lack of appropriate methodologies for in-situ non-destructive root characterization. Recent studies show that interactive effects of plant neighbourhood interactions follow non-linear and non-additive paths that are hard to explain. Common outcomes such as accumulation of roots mainly in the topsoil cannot be explained solely by competition theory but require a more inclusive theoretical, as well as an improved methodological framework. This will include the question of whether we can apply the same conceptual framework to crop versus natural species. The development of non-invasive methods to dynamically study root-root interactions in vivo will provide the necessary tools to study a more inclusive conceptual framework for root-root interactions. By following the dynamics of root-root interactions through time in a whole range of scenarios and systems, using a wide variety of non-invasive methods, (such as fluorescent protein which now allows us to separately identify the roots of several individuals within soil), we will be much better equipped to answer some of the key questions in root physiology, ecology and agronomy.

  12. Root–root interactions: extending our perspective to be more inclusive of the range of theories in ecology and agriculture using in-vivo analyses

    Science.gov (United States)

    Faget, Marc; Nagel, Kerstin A.; Walter, Achim; Herrera, Juan M.; Jahnke, Siegfried; Schurr, Ulrich; Temperton, Vicky M.

    2013-01-01

    Background There is a large body of literature on competitive interactions among plants, but many studies have only focused on above-ground interactions and little is known about root–root dynamics between interacting plants. The perspective on possible mechanisms that explain the outcome of root–root interactions has recently been extended to include non-resource-driven mechanisms (as well as resource-driven mechanisms) of root competition and positive interactions such as facilitation. These approaches have often suffered from being static, partly due to the lack of appropriate methodologies for in-situ non-destructive root characterization. Scope Recent studies show that interactive effects of plant neighbourhood interactions follow non-linear and non-additive paths that are hard to explain. Common outcomes such as accumulation of roots mainly in the topsoil cannot be explained solely by competition theory but require a more inclusive theoretical, as well as an improved methodological framework. This will include the question of whether we can apply the same conceptual framework to crop versus natural species. Conclusions The development of non-invasive methods to dynamically study root–root interactions in vivo will provide the necessary tools to study a more inclusive conceptual framework for root–root interactions. By following the dynamics of root–root interactions through time in a whole range of scenarios and systems, using a wide variety of non-invasive methods, (such as fluorescent protein which now allows us to separately identify the roots of several individuals within soil), we will be much better equipped to answer some of the key questions in root physiology, ecology and agronomy. PMID:23378521

  13. Exposure to Violence across the Social Ecosystem and the Development of Aggression: A Test of Ecological Theory in the Israeli-Palestinian Conflict

    Science.gov (United States)

    Boxer, Paul; Huesmann, L. Rowell; Dubow, Eric F.; Landau, Simha F.; Gvirsman, Shira Dvir; Shikaki, Khalil; Ginges, Jeremy

    2013-01-01

    Bronfenbrenner's (1979) ecological model proposes that events in higher order social ecosystems should influence human development through their impact on events in lower order social ecosystems. This proposition was tested with respect to ecological violence and the development of children's aggression via analyses of 3 waves of data (1 wave…

  14. The evolutionary ecology of molecular replicators.

    Science.gov (United States)

    Nee, Sean

    2016-08-01

    By reasonable criteria, life on the Earth consists mainly of molecular replicators. These include viruses, transposons, transpovirons, coviruses and many more, with continuous new discoveries like Sputnik Virophage. Their study is inherently multidisciplinary, spanning microbiology, genetics, immunology and evolutionary theory, and the current view is that taking a unified approach has great power and promise. We support this with a new, unified, model of their evolutionary ecology, using contemporary evolutionary theory coupling the Price equation with game theory, studying the consequences of the molecular replicators' promiscuous use of each others' gene products for their natural history and evolutionary ecology. Even at this simple expository level, we can make a firm prediction of a new class of replicators exploiting viruses such as lentiviruses like SIVs, a family which includes HIV: these have been explicitly stated in the primary literature to be non-existent. Closely connected to this departure is the view that multicellular organism immunology is more about the management of chronic infections rather than the elimination of acute ones and new understandings emerging are changing our view of the kind of theatre we ourselves provide for the evolutionary play of molecular replicators. This study adds molecular replicators to bacteria in the emerging field of sociomicrobiology.

  15. Resource ecology : spatial and temporal dynamics of foraging

    NARCIS (Netherlands)

    Prins, H.H.T.; Langevelde, van F.

    2008-01-01

    This multi-author book deals with 'resource ecology', which is the ecology of trophic interactions between consumers and their resources. Resource ecology is perhaps the most central part of ecology. In its linkage between foraging theory and spatial ecology, it shows how old and fundamental

  16. Framework for ecological risk assessment

    International Nuclear Information System (INIS)

    Rodier, D.; Norton, S.

    1992-02-01

    Increased interest in ecological issues such as global climate change, habitat loss, acid deposition, reduced biological diversity, and the ecological impacts of pesticides and toxic chemicals prompts this U.S. Environmental Protection Agency (EPA) report, A Framework for Ecological Risk Assessment ('Framework Report'). The report describes basic elements, or a framework, for evaluating scientific information on the adverse effects of physical and chemical stressors on the environment. The framework offers starting principles and a simple structure as guidance for current ecological risk assessments and as a foundation for future EPA proposals for risk assessment guidelines

  17. ECOLOGICAL ECONOMICS AND LITERARY COMMUNICATION ...

    African Journals Online (AJOL)

    GRACE

    development between standard economic and ecological theories. ... environmental issues that affect the econiche, and for exploring human conditions and ... about medium, about intention and its signaling via contextualization cues—―are.

  18. Microbiology of the phyllosphere: a playground for testing ecological concepts

    NARCIS (Netherlands)

    Meyer, K.M.; Leveau, J.H.J.

    2012-01-01

    Many concepts and theories in ecology are highly debated, because it is often difficult to design decisive tests with sufficient replicates. Examples include biodiversity theories, succession concepts, invasion theories, coexistence theories, and concepts of life history strategies. Microbiological

  19. Statistical ecology comes of age

    Science.gov (United States)

    Gimenez, Olivier; Buckland, Stephen T.; Morgan, Byron J. T.; Bez, Nicolas; Bertrand, Sophie; Choquet, Rémi; Dray, Stéphane; Etienne, Marie-Pierre; Fewster, Rachel; Gosselin, Frédéric; Mérigot, Bastien; Monestiez, Pascal; Morales, Juan M.; Mortier, Frédéric; Munoz, François; Ovaskainen, Otso; Pavoine, Sandrine; Pradel, Roger; Schurr, Frank M.; Thomas, Len; Thuiller, Wilfried; Trenkel, Verena; de Valpine, Perry; Rexstad, Eric

    2014-01-01

    The desire to predict the consequences of global environmental change has been the driver towards more realistic models embracing the variability and uncertainties inherent in ecology. Statistical ecology has gelled over the past decade as a discipline that moves away from describing patterns towards modelling the ecological processes that generate these patterns. Following the fourth International Statistical Ecology Conference (1–4 July 2014) in Montpellier, France, we analyse current trends in statistical ecology. Important advances in the analysis of individual movement, and in the modelling of population dynamics and species distributions, are made possible by the increasing use of hierarchical and hidden process models. Exciting research perspectives include the development of methods to interpret citizen science data and of efficient, flexible computational algorithms for model fitting. Statistical ecology has come of age: it now provides a general and mathematically rigorous framework linking ecological theory and empirical data. PMID:25540151

  20. Statistical ecology comes of age.

    Science.gov (United States)

    Gimenez, Olivier; Buckland, Stephen T; Morgan, Byron J T; Bez, Nicolas; Bertrand, Sophie; Choquet, Rémi; Dray, Stéphane; Etienne, Marie-Pierre; Fewster, Rachel; Gosselin, Frédéric; Mérigot, Bastien; Monestiez, Pascal; Morales, Juan M; Mortier, Frédéric; Munoz, François; Ovaskainen, Otso; Pavoine, Sandrine; Pradel, Roger; Schurr, Frank M; Thomas, Len; Thuiller, Wilfried; Trenkel, Verena; de Valpine, Perry; Rexstad, Eric

    2014-12-01

    The desire to predict the consequences of global environmental change has been the driver towards more realistic models embracing the variability and uncertainties inherent in ecology. Statistical ecology has gelled over the past decade as a discipline that moves away from describing patterns towards modelling the ecological processes that generate these patterns. Following the fourth International Statistical Ecology Conference (1-4 July 2014) in Montpellier, France, we analyse current trends in statistical ecology. Important advances in the analysis of individual movement, and in the modelling of population dynamics and species distributions, are made possible by the increasing use of hierarchical and hidden process models. Exciting research perspectives include the development of methods to interpret citizen science data and of efficient, flexible computational algorithms for model fitting. Statistical ecology has come of age: it now provides a general and mathematically rigorous framework linking ecological theory and empirical data.

  1. Development of a simple 12-item theory-based instrument to assess the impact of continuing professional development on clinical behavioral intentions.

    Directory of Open Access Journals (Sweden)

    France Légaré

    Full Text Available Decision-makers in organizations providing continuing professional development (CPD have identified the need for routine assessment of its impact on practice. We sought to develop a theory-based instrument for evaluating the impact of CPD activities on health professionals' clinical behavioral intentions.Our multipronged study had four phases. 1 We systematically reviewed the literature for instruments that used socio-cognitive theories to assess healthcare professionals' clinically-oriented behavioral intentions and/or behaviors; we extracted items relating to the theoretical constructs of an integrated model of healthcare professionals' behaviors and removed duplicates. 2 A committee of researchers and CPD decision-makers selected a pool of items relevant to CPD. 3 An international group of experts (n = 70 reached consensus on the most relevant items using electronic Delphi surveys. 4 We created a preliminary instrument with the items found most relevant and assessed its factorial validity, internal consistency and reliability (weighted kappa over a two-week period among 138 physicians attending a CPD activity. Out of 72 potentially relevant instruments, 47 were analyzed. Of the 1218 items extracted from these, 16% were discarded as improperly phrased and 70% discarded as duplicates. Mapping the remaining items onto the constructs of the integrated model of healthcare professionals' behaviors yielded a minimum of 18 and a maximum of 275 items per construct. The partnership committee retained 61 items covering all seven constructs. Two iterations of the Delphi process produced consensus on a provisional 40-item questionnaire. Exploratory factorial analysis following test-retest resulted in a 12-item questionnaire. Cronbach's coefficients for the constructs varied from 0.77 to 0.85.A 12-item theory-based instrument for assessing the impact of CPD activities on health professionals' clinical behavioral intentions showed adequate validity and

  2. Nutrition, ecology and nutritional ecology: towardan integrated framework

    DEFF Research Database (Denmark)

    Raubenheimer, David; Simpson, Steven J.; Mayntz, David

    2009-01-01

    requirements: it should be nutritionally explicit, organismally explicit, and ecologically explicit. 4. We evaluate against these criteria four existing frameworks (Optimal Foraging Theory, Classical Insect Nutritional Ecology, the Geometric Framework for nutrition, and Ecological Stoichiometry), and conclude...... in its own right? 2. We suggest that the distinctive feature of nutritional ecology is its integrative nature, and that the field would benefit from more attention to formalizing a theoretical and quantitative framework for developing this. 3. Such a framework, we propose, should satisfy three minimal...

  3. Gravitational Contribution to the Heat Flux in a Simple Dilute Fluid: An Approach Based on General Relativistic Kinetic Theory to First Order in the Gradients

    Directory of Open Access Journals (Sweden)

    Dominique Brun-Battistini

    2017-10-01

    Full Text Available Richard C. Tolman analyzed the relation between a temperature gradient and a gravitational field in an equilibrium situation. In 2012, Tolman’s law was generalized to a non-equilibrium situation for a simple dilute relativistic fluid. The result in that scenario, obtained by introducing the gravitational force through the molecular acceleration, couples the heat flux with the metric coefficients and the gradients of the state variables. In the present paper it is shown, by explicitly describing the single particle orbits as geodesics in Boltzmann’s equation, that a gravitational field drives a heat flux in this type of system. The calculation is devoted solely to the gravitational field contribution to this heat flux in which a Newtonian limit to the Schwarzschild metric is assumed. The corresponding transport coefficient, which is obtained within a relaxation approximation, corresponds to the dilute fluid in a weak gravitational field. The effect is negligible in the non-relativistic regime, as evidenced by the direct evaluation of the corresponding limit.

  4. Group Theory and Crystal Field Theory: A Simple and Rigorous Derivation of the Spectroscopic Terms Generated by the t[subscript 2g][superscript 2] Electronic Configuration in a Strong Octahedral Field

    Science.gov (United States)

    Morpurgo, Simone

    2007-01-01

    The principles of symmetry and group theory are applied to the zero-order wavefunctions associated with the strong-field t[subscript 2g][superscript 2] configuration and their symmetry-adapted linear combinations (SALC) associated with the generated energy terms are derived. This approach will enable students to better understand the use of…

  5. You can take a horse to water ...environmental education theory and ...

    African Journals Online (AJOL)

    You can take a horse to water ...environmental education theory and practice in the context of a simple freshwater ecology exercise. ... It questions the educational benefits of teaching and learning that rely on the transmission of information, and explores an alternative epistemological basis for such work. It suggests that a ...

  6. Landscape Ecology

    DEFF Research Database (Denmark)

    Christensen, Andreas Aagaard; Brandt, Jesper; Svenningsen, Stig Roar

    2017-01-01

    Landscape ecology is an interdisciplinary field of research and practice that deals with the mutual association between the spatial configuration and ecological functioning of landscapes, exploring and describing processes involved in the differentiation of spaces within landscapes......, and the ecological significance of the patterns which are generated by such processes. In landscape ecology, perspectives drawn from existing academic disciplines are integrated based on a common, spatially explicit mode of analysis developed from classical holistic geography, emphasizing spatial and landscape...... pattern analysis and ecological interaction of land units. The landscape is seen as a holon: an assemblage of interrelated phenomena, both cultural and biophysical, that together form a complex whole. Enduring challenges to landscape ecology include the need to develop a systematic approach able...

  7. Making ecological models adequate

    Science.gov (United States)

    Getz, Wayne M.; Marshall, Charles R.; Carlson, Colin J.; Giuggioli, Luca; Ryan, Sadie J.; Romañach, Stephanie; Boettiger, Carl; Chamberlain, Samuel D.; Larsen, Laurel; D'Odorico, Paolo; O'Sullivan, David

    2018-01-01

    Critical evaluation of the adequacy of ecological models is urgently needed to enhance their utility in developing theory and enabling environmental managers and policymakers to make informed decisions. Poorly supported management can have detrimental, costly or irreversible impacts on the environment and society. Here, we examine common issues in ecological modelling and suggest criteria for improving modelling frameworks. An appropriate level of process description is crucial to constructing the best possible model, given the available data and understanding of ecological structures. Model details unsupported by data typically lead to over parameterisation and poor model performance. Conversely, a lack of mechanistic details may limit a model's ability to predict ecological systems’ responses to management. Ecological studies that employ models should follow a set of model adequacy assessment protocols that include: asking a series of critical questions regarding state and control variable selection, the determinacy of data, and the sensitivity and validity of analyses. We also need to improve model elaboration, refinement and coarse graining procedures to better understand the relevancy and adequacy of our models and the role they play in advancing theory, improving hind and forecasting, and enabling problem solving and management.

  8. Exposure to violence across the social ecosystem and the development of aggression: a test of ecological theory in the Israeli-Palestinian conflict.

    Science.gov (United States)

    Boxer, Paul; Rowell Huesmann, L; Dubow, Eric F; Landau, Simha F; Gvirsman, Shira Dvir; Shikaki, Khalil; Ginges, Jeremy

    2013-01-01

    Bronfenbrenner's (1979) ecological model proposes that events in higher order social ecosystems should influence human development through their impact on events in lower order social ecosystems. This proposition was tested with respect to ecological violence and the development of children's aggression via analyses of 3 waves of data (1 wave yearly for 3 years) from 3 age cohorts (starting ages: 8, 11, and 14) representing three populations in the Middle East: Palestinians (N = 600), Israeli Jews (N = 451), and Israeli Arabs (N = 450). Results supported a hypothesized model in which ethnopolitical violence increases community, family, and school violence and children's aggression. Findings are discussed with respect to ecological and observational learning perspectives on the development of aggressive behavior. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

  9. The anisotropic Ising superantiferromagnet on a simple cubic lattice in the presence of a magnetic field: Effective-field theory analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ricardo de Sousa, J. [Universidade Federal do Amazonas, Departamento de Física, 3000, Japiim, 69077-000 Manaus, AM (Brazil); National Institute of Science and Technology for Complex Systems, 3000, Japiim, 69077-000 Manaus, AM (Brazil); Neto, Minos A., E-mail: minos@pq.cnpq.br [Universidade Federal do Amazonas, Departamento de Física, 3000, Japiim, 69077-000 Manaus, AM (Brazil); Padilha, Igor T.; Salmon, Octavio D.R.; Viana, J. Roberto [Universidade Federal do Amazonas, Departamento de Física, 3000, Japiim, 69077-000 Manaus, AM (Brazil)

    2013-12-15

    We have studied the anisotropic three-dimensional nearest-neighbor Ising model with competitive interactions in an uniform longitudinal magnetic field H. The model consists of ferromagnetic interactions J{sub z}=λ{sub 2}J{sub x} in the x(z) direction and antiferromagnetic interactions J{sub y}=λ{sub 1}J{sub x} in the y direction (Ising superantiferromagnet). For the particular case λ{sub 1}=λ{sub 2}=1 we obtain the phase diagram in the H−T plane, using the framework of the differential operator technique in the effective-field theory with finite cluster of N=4 spins (EFT-4). It was observed first- and second-order transitions in the low and high temperature limits, respectively, with the presence of a tricritical point and a reentrant behavior is observed at low temperature. The critical curve in the classical approach is also obtained and the results are compared.

  10. Toward an Agathocentric Ecology

    Directory of Open Access Journals (Sweden)

    Erazim Kohák

    2007-04-01

    Full Text Available I should like to submit to you a simple, basic thesis--that what we are accustomed to calling the "ecological crisis" is not a product of a conflict between human needs and the needs of nature but of a flawed perception of what our needs in truth are. It is, I believe, a crisis of our humanity rather than one of nature or technology, and so requires not only technological but also humanistic answers.

  11. Simple Tidal Prism Models Revisited

    Science.gov (United States)

    Luketina, D.

    1998-01-01

    Simple tidal prism models for well-mixed estuaries have been in use for some time and are discussed in most text books on estuaries. The appeal of this model is its simplicity. However, there are several flaws in the logic behind the model. These flaws are pointed out and a more theoretically correct simple tidal prism model is derived. In doing so, it is made clear which effects can, in theory, be neglected and which can not.

  12. Editorial : Laudation to prof.dr. Hans-Toni Tarre- towards conceptual, theory-based ecological science and its transfer to the applied field of ecotoxicology

    NARCIS (Netherlands)

    Brock, T.C.M.; Giesy, J.P.; Heimbach, F.; Hollert, H.; Ross-Nickoll, M.; Schaffer, A.; Steinhauser, K.G.

    2011-01-01

    In order to thank Prof. Dr. Hans-Toni Ratte on the occasion of his retirement for his outstanding experimental and modelling merits in the field of ecotoxicology and ecology and his personal 65th anniversary on November 25th this article will present a laudation.

  13. Landscape Ecology

    DEFF Research Database (Denmark)

    Christensen, Andreas Aagaard; Brandt, Jesper; Svenningsen, Stig Roar

    2017-01-01

    , and the ecological significance of the patterns which are generated by such processes. In landscape ecology, perspectives drawn from existing academic disciplines are integrated based on a common, spatially explicit mode of analysis developed from classical holistic geography, emphasizing spatial and landscape...... to translate positivist readings of the environment and hermeneutical perspectives on socioecological interaction into a common framework or terminology....

  14. Development and characteristics of applied ecology

    OpenAIRE

    Sooth, Farina

    2014-01-01

    Master i anvendt økologi. Evenstad 2014 The science of applied ecology is lacking a general theory and a commonly acknowledged definition. Additionally, information about the development of applied ecology over the past years, the relation to other disciplines and the importance of applied ecology in different continents are scarce. This is problematic because applied ecology is confronted with growing problems and the society demands more and more that it fulfils its promise of solving pr...

  15. Classification of simple current invariants

    CERN Document Server

    Gato-Rivera, Beatriz

    1992-01-01

    We summarize recent work on the classification of modular invariant partition functions that can be obtained with simple currents in theories with a center (Z_p)^k with p prime. New empirical results for other centers are also presented. Our observation that the total number of invariants is monodromy-independent for (Z_p)^k appears to be true in general as well. (Talk presented in the parallel session on string theory of the Lepton-Photon/EPS Conference, Geneva, 1991.)

  16. Interim balance: Ecology

    International Nuclear Information System (INIS)

    Kogon, E.; Jungk, R.

    1981-01-01

    Subjects: The ecology problem - world wide. Sectoral balances: The examples of energy, transportation, chemistry, agriculture and food industry, water supply. Destruction of nature and human discord. Conservatives in our political parties and their views on environmental protection. Alliance between reds and 'greens', integration between reds and greens. The Rhine initiative. Lead respects no borders, experiences of citizens' action groups in Lothringia and the Saar district. International airport Munich-II/comments by a protestant. 'Give priority to life'/A hearing on environmental protection. 4:96 - 'greens' in the Bremen Senate. Policy in a hard-hearing world/psychology of citizens' action groups. Critical ecological research and scientific establishment. Full productivity and ecology. The deluge to follow/Hints on how to build an ark. Symbiosis is more than coexistence/Ecologists' social theory. Throwing in two hundred elementary particles/on the way to an ecological concept of science. Scientific journals. Alternative literature. Teaching model for a teaching subject 'ecology'. (orig.) [de

  17. Molecular ecological network analyses.

    Science.gov (United States)

    Deng, Ye; Jiang, Yi-Huei; Yang, Yunfeng; He, Zhili; Luo, Feng; Zhou, Jizhong

    2012-05-30

    Understanding the interaction among different species within a community and their responses to environmental changes is a central goal in ecology. However, defining the network structure in a microbial community is very challenging due to their extremely high diversity and as-yet uncultivated status. Although recent advance of metagenomic technologies, such as high throughout sequencing and functional gene arrays, provide revolutionary tools for analyzing microbial community structure, it is still difficult to examine network interactions in a microbial community based on high-throughput metagenomics data. Here, we describe a novel mathematical and bioinformatics framework to construct ecological association networks named molecular ecological networks (MENs) through Random Matrix Theory (RMT)-based methods. Compared to other network construction methods, this approach is remarkable in that the network is automatically defined and robust to noise, thus providing excellent solutions to several common issues associated with high-throughput metagenomics data. We applied it to determine the network structure of microbial communities subjected to long-term experimental warming based on pyrosequencing data of 16 S rRNA genes. We showed that the constructed MENs under both warming and unwarming conditions exhibited topological features of scale free, small world and modularity, which were consistent with previously described molecular ecological networks. Eigengene analysis indicated that the eigengenes represented the module profiles relatively well. In consistency with many other studies, several major environmental traits including temperature and soil pH were found to be important in determining network interactions in the microbial communities examined. To facilitate its application by the scientific community, all these methods and statistical tools have been integrated into a comprehensive Molecular Ecological Network Analysis Pipeline (MENAP), which is open

  18. Community Ecology

    CERN Document Server

    1988-01-01

    This book presents the proceedings of a workshop on community ecology organized at Davis, in April, 1986, sponsored by the Sloan Foundation. There have been several recent symposia on community ecology (Strong et. al., 1984, Diamond and Case, 1987) which have covered a wide range of topics. The goal of the workshop at Davis was more narrow: to explore the role of scale in developing a theoretical approach to understanding communities. There are a number of aspects of scale that enter into attempts to understand ecological communities. One of the most basic is organizational scale. Should community ecology proceed by building up from population biology? This question and its ramifications are stressed throughout the book and explored in the first chapter by Simon Levin. Notions of scale have long been important in understanding physical systems. Thus, in understanding the interactions of organisms with their physical environment, questions of scale become paramount. These more physical questions illustrate the...

  19. Nutritional Ecology and Human Health.

    Science.gov (United States)

    Raubenheimer, David; Simpson, Stephen J

    2016-07-17

    In contrast to the spectacular advances in the first half of the twentieth century with micronutrient-related diseases, human nutrition science has failed to stem the more recent rise of obesity and associated cardiometabolic disease (OACD). This failure has triggered debate on the problems and limitations of the field and what change is needed to address these. We briefly review the two broad historical phases of human nutrition science and then provide an overview of the main problems that have been implicated in the poor progress of the field with solving OACD. We next introduce the field of nutritional ecology and show how its ecological-evolutionary foundations can enrich human nutrition science by providing the theory to help address its limitations. We end by introducing a modeling approach from nutritional ecology, termed nutritional geometry, and demonstrate how it can help to implement ecological and evolutionary theory in human nutrition to provide new direction and to better understand and manage OACD.

  20. Simple theory of nonleptonic kaon decays

    International Nuclear Information System (INIS)

    Scadron, M.D.; Choudhury, S.R.

    1987-07-01

    We first summarize (a) why the quark s-bar-d-bar loop transition dominated by the physical W + exchange controls the large ΔI=1/2 K π and K 2π o nonleptonic decay amplitudes, and (b) why the vacuum-saturated hadronic (implied W + ) current-current hamiltonian correctly explains the small ΔI-3/2 K 2π + decay. Then we study in greater detail a more complete hadronic D.K.π meson-W ± loop calculation of the ΔI=1/2 and ΔI=3/2 K 2π amplitudes and show that this picture further reinforces our original quark ΔI=1/2 and hadron vacuum-saturated ΔI=3/2 (long distance) scheme. (author). 29 refs, 8 figs

  1. Stochastic Spatial Models in Ecology: A Statistical Physics Approach

    Science.gov (United States)

    Pigolotti, Simone; Cencini, Massimo; Molina, Daniel; Muñoz, Miguel A.

    2017-11-01

    Ecosystems display a complex spatial organization. Ecologists have long tried to characterize them by looking at how different measures of biodiversity change across spatial scales. Ecological neutral theory has provided simple predictions accounting for general empirical patterns in communities of competing species. However, while neutral theory in well-mixed ecosystems is mathematically well understood, spatial models still present several open problems, limiting the quantitative understanding of spatial biodiversity. In this review, we discuss the state of the art in spatial neutral theory. We emphasize the connection between spatial ecological models and the physics of non-equilibrium phase transitions and how concepts developed in statistical physics translate in population dynamics, and vice versa. We focus on non-trivial scaling laws arising at the critical dimension D = 2 of spatial neutral models, and their relevance for biological populations inhabiting two-dimensional environments. We conclude by discussing models incorporating non-neutral effects in the form of spatial and temporal disorder, and analyze how their predictions deviate from those of purely neutral theories.

  2. The role of Dynamic Energy Budget theory in predictive modeling of stressor impacts on ecological systems. Comment on: ;Physics of metabolic organization; by Marko Jusup et al.

    Science.gov (United States)

    Galic, Nika; Forbes, Valery E.

    2017-03-01

    Human activities have been modifying ecosystems for centuries, from pressures on wild populations we harvest to modifying habitats through urbanization and agricultural activities. Changes in global climate patterns are adding another layer of, often unpredictable, perturbations to ecosystems on which we rely for life support [1,2]. To ensure the sustainability of ecosystem services, especially at this point in time when the human population is estimated to grow by another 2 billion by 2050 [3], we need to predict possible consequences of our actions and suggest relevant solutions [4,5]. We face several challenges when estimating adverse impacts of our actions on ecosystems. We describe these in the context of ecological risk assessment of chemicals. Firstly, when attempting to assess risk from exposure to chemicals, we base our decisions on a very limited number of species that are easily cultured and kept in the lab. We assume that preventing risk to these species will also protect all of the untested species present in natural ecosystems [6]. Secondly, although we know that chemicals interact with other stressors in the field, the number of stressors that we can test is limited due to logistical and ethical reasons. Similarly, empirical approaches are limited in both spatial and temporal scale due to logistical, financial and ethical reasons [7,8]. To bypass these challenges, we can develop ecological models that integrate relevant life history and other information and make testable predictions across relevant spatial and temporal scales [8-10].

  3. Using social-ecological systems theory to evaluate large-scale comanagement efforts: a case study of the Inuvialuit Settlement Region

    Directory of Open Access Journals (Sweden)

    William Tyson

    2017-03-01

    Full Text Available Comanagement efforts are increasingly tasked with overseeing natural resource governance at a large scale. I examine comanagement of subsistence harvesting in the Inuvialuit Settlement Region (ISR of the western Canadian Arctic, using a social-ecological systems framework. In doing so, this study joins a growing list of research that reviews design principles commonly found in successful small-scale commons management and applies them to a large resource area. This research uses the management of beluga (Delphinapterus leucas and barren-ground caribou (Rangifer tarandus groenlandicus as case studies in understanding the management framework of the Inuvialuit Settlement Region, as each species is important in Inuvialuit culture and is actively managed and monitored. Comanagement bodies in the study area display many of the institutional design principles that are characteristic of successful social-ecological systems. Particularly mentionable are the presence of well-organized nested enterprises and a strong incorporation of local knowledge and monitoring. This supports the application of institutional design principles in large-scale analyses of resource management. However, due to the network of policy and management outside the ISR that influences each species, this research suggests that in cases of wide-ranging resource bases, these types of analyses may be better suited to evaluating broad management networks rather than discrete governing regions.

  4. Designing mental health interventions informed by child development and human biology theory: a social ecology intervention for child soldiers in Nepal.

    Science.gov (United States)

    Kohrt, Brandon A; Jordans, Mark J D; Koirala, Suraj; Worthman, Carol M

    2015-01-01

    The anthropological study of human biology, health, and child development provides a model with potential to address the gap in population-wide mental health interventions. Four key concepts from human biology can inform public mental health interventions: life history theory and tradeoffs, redundancy and plurality of pathways, cascades and multiplier effects in biological systems, and proximate feedback systems. A public mental health intervention for former child soldiers in Nepal is used to illustrate the role of these concepts in intervention design and evaluation. Future directions and recommendations for applying human biology theory in pursuit of public mental health interventions are discussed. © 2014 Wiley Periodicals, Inc.

  5. Ecological macroeconomics

    DEFF Research Database (Denmark)

    Røpke, Inge

    2013-01-01

    by a more theoretical debate and increased interaction between the heterodox schools of ecological economics and post-Keynesian economics. In addition, both the degrowth community and the research community organized around sustainable transitions of socio-technical systems have contributed to discussions...... on how to reconcile environmental and social concerns. Based on this broad variety of pieces in a jigsaw puzzle, a new ecological macroeconomics is emerging, but the contours are still vague. This chapter seeks to outline some of this topography and to add a few pieces of its own by highlighting the need...... to shift resources from consumption to investment and describing the role of consumer-citizens in such a change. The chapter starts by identifying the problems and challenges for an ecological macroeconomics. The next section outlines some of the shortcomings of traditional macroeconomics...

  6. Macrophytes: Ecology of aquatic plants

    NARCIS (Netherlands)

    Bornette, G.; Puijalon, S.

    2009-01-01

    Aquatic plants contribute to maintaining key functions and related biodiversity in freshwater ecosystems, and to provide the needs of human societies. The way the ecological niches of macrophytes are determined by abiotic filters and biotic ones is considered. A simple, broadly applicable model of

  7. Theoretical ecology as etiological from the start.

    Science.gov (United States)

    Donhauser, Justin

    2016-12-01

    The world's leading environmental advisory institutions look to ecological theory and research as an objective guide for policy and resource management decision-making. In addition to the theoretical and broadly philosophical merits of doing so, it is therefore practically significant to clear up confusions about ecology's conceptual foundations and to clarify the basic workings of inferential methods used in the science. Through discussion of key moments in the genesis of the theoretical branch of ecology, this essay elucidates a general heuristic role of teleological metaphors in ecological research and defuses certain enduring confusions about work in ecology. Copyright © 2016. Published by Elsevier Ltd.

  8. Ecology-driven stereotypes override race stereotypes

    Science.gov (United States)

    Williams, Keelah E. G.; Sng, Oliver; Neuberg, Steven L.

    2016-01-01

    Why do race stereotypes take the forms they do? Life history theory posits that features of the ecology shape individuals’ behavior. Harsh and unpredictable (“desperate”) ecologies induce fast strategy behaviors such as impulsivity, whereas resource-sufficient and predictable (“hopeful”) ecologies induce slow strategy behaviors such as future focus. We suggest that individuals possess a lay understanding of ecology’s influence on behavior, resulting in ecology-driven stereotypes. Importantly, because race is confounded with ecology in the United States, we propose that Americans’ stereotypes about racial groups actually reflect stereotypes about these groups’ presumed home ecologies. Study 1 demonstrates that individuals hold ecology stereotypes, stereotyping people from desperate ecologies as possessing faster life history strategies than people from hopeful ecologies. Studies 2–4 rule out alternative explanations for those findings. Study 5, which independently manipulates race and ecology information, demonstrates that when provided with information about a person’s race (but not ecology), individuals’ inferences about blacks track stereotypes of people from desperate ecologies, and individuals’ inferences about whites track stereotypes of people from hopeful ecologies. However, when provided with information about both the race and ecology of others, individuals’ inferences reflect the targets’ ecology rather than their race: black and white targets from desperate ecologies are stereotyped as equally fast life history strategists, whereas black and white targets from hopeful ecologies are stereotyped as equally slow life history strategists. These findings suggest that the content of several predominant race stereotypes may not reflect race, per se, but rather inferences about how one’s ecology influences behavior. PMID:26712013

  9. Simple Perturbation Example for Quantum Chemistry.

    Science.gov (United States)

    Goodfriend, P. L.

    1985-01-01

    Presents a simple example that illustrates various aspects of the Rayleigh-Schrodinger perturbation theory. The example is a particularly good one because it is straightforward and can be compared with both the exact solution and with experimental data. (JN)

  10. Simple Kidney Cysts

    Science.gov (United States)

    ... Solitary Kidney Your Kidneys & How They Work Simple Kidney Cysts What are simple kidney cysts? Simple kidney cysts are abnormal, fluid-filled ... that form in the kidneys. What are the kidneys and what do they do? The kidneys are ...

  11. Ecological concepts

    International Nuclear Information System (INIS)

    1986-01-01

    This volume contains three critical contributions on the application of modern technology from the ethical point of view. The peaceful use of nuclear power is rejected as a technical error, which is overwhelming humanity. Ethical bases of a preventive technological policy and ecological aims are developed for the 21st century, in economy, technology, politics, and consciousness. (HSCH) [de

  12. Gradings on simple Lie algebras

    CERN Document Server

    Elduque, Alberto

    2013-01-01

    Gradings are ubiquitous in the theory of Lie algebras, from the root space decomposition of a complex semisimple Lie algebra relative to a Cartan subalgebra to the beautiful Dempwolff decomposition of E_8 as a direct sum of thirty-one Cartan subalgebras. This monograph is a self-contained exposition of the classification of gradings by arbitrary groups on classical simple Lie algebras over algebraically closed fields of characteristic not equal to 2 as well as on some nonclassical simple Lie algebras in positive characteristic. Other important algebras also enter the stage: matrix algebras, the octonions, and the Albert algebra. Most of the presented results are recent and have not yet appeared in book form. This work can be used as a textbook for graduate students or as a reference for researchers in Lie theory and neighboring areas.

  13. Political ecology

    International Nuclear Information System (INIS)

    Strohm, H.

    1979-01-01

    Using facts and examples, this didactically structures textbook gives an insight into the extent and consequences of the damage to the environment, with the subjects - fundamentals of ecology; - population and food problems; - the energy problem; - economic growth; scarcity of resources, recycling; - ground, water, and air pollution, - city and traffic problems; - work protection and medical care; - political alternatives and 'soft technologies'. The analysis of the political and economic reasons is combined with social and technical alternatives from which demands to be made and measures to be taken can be derived for individuals, citizens' interest groups, political groups and trade unions. Teaching models intend to help teachers to work on specific problems of ecology. (orig.) [de

  14. Wasteland ecologies

    DEFF Research Database (Denmark)

    Hoag, Colin Brewster; Bertoni, Filippo; Bubandt, Nils Ole

    2018-01-01

    landscapes, this article argues, are the result of unheralded multispecies collaboration that can be traced empirically by attending ethnographically to multispecies forms of “gain-making,” the ways in which humans and other species leverage difference to find economic and ecological opportunity....... in the 1970s, when prevailing perceptions were that the entire mining area was a polluted wasteland, the AFLD Fasterholt waste and recycling plant has since changed in response to new EU waste management regulations, as well as the unexpected proliferation of non-human life in the area. Based on field...... research at this site—an Anthropocene landscape in the heartland of an EU-configured welfare state — this article is a contribution to the multispecies ethnography and political ecology of wastelands. We argue that “waste” is a co-species, biopolitical happening — a complex symbolic, political, biological...

  15. Marine ecology

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Studies on marine ecology included marine pollution; distribution patterns of Pu and Am in the marine waters, sediments, and organisms of Bikini Atoll and the influence of physical, chemical, and biological factors on their movements through marine biogeochemical systems; transfer and dispersion of organic pollutants from an oil refinery through coastal waters; transfer of particulate pollutants, including sediments dispersed during construction of offshore power plants; and raft culture of the mangrove oysters

  16. Terrestrial ecology

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    The main effort of the Terrestrial Ecology Division has been redirected to a comprehensive study of the Espiritu Santo Drainage Basin located in northeastern Puerto Rico. The general objective are to provide baseline ecological data for future environmental assessment studies at the local and regional levels, and to provide through an ecosystem approach data for the development of management alternatives for the wise utilization of energy, water, and land resources. The interrelationships among climate, vegetation, soils, and man, and their combined influence upon the hydrologic cycle will be described and evaluated. Environmental management involves planning and decision making, and both require an adequate data base. At present, little is known about the interworkings of a complete, integrated system such as a drainage basin. A literature survey of the main research areas confirmed that, although many individual ecologically oriented studies have been carried out in a tropical environment, few if any provide the data base required for environmental management. In view of rapidly changing socio-economic conditions and natural resources limitations, management urgently requires data from these systems: physical (climatological), biological, and cultural. This integrated drainage basin study has been designed to provide such data. The scope of this program covers the hydrologic cycle as it is affected by the interactions of the physical, biological, and cultural systems

  17. Understanding cities as social-ecological systems

    CSIR Research Space (South Africa)

    Du Plessis, C

    2008-09-01

    Full Text Available This paper builds on earlier ecological approaches to urban development, as well as more recent thinking in the fields of sustainability science, resilience thinking and complexity theory, to propose a conceptual framework for understanding cities...

  18. Introduction: Social-Ecological Resilience and Law

    Science.gov (United States)

    Environmental law envisions ecological systems as existing in an equilibrium state, reinforcing a rigid legal framework unable to absorb rapid environmental changes and innovations in sustainability. For the past four decades, "resilience theory," which embraces uncertainty and n...

  19. Ecological niche of plant pathogens

    Directory of Open Access Journals (Sweden)

    Ecaterina Fodor

    2011-06-01

    Full Text Available Disease ecology is a new approach to the understanding of the spread and dynamics of pathogens in natural and man-made environments. Defining and describing the ecological niche of the pathogens is one of the major tasks for ecological theory, as well as for practitioners preoccupied with the control and forecasting of established and emerging diseases. Niche theory has been periodically revised, not including in an explicit way the pathogens. However, many progresses have been achieved in niche modeling of disease spread, but few attempts were made to construct a theoretical frame for the ecological niche of pathogens. The paper is a review of the knowledge accumulated during last decades in the niche theory of pathogens and proposes an ecological approach in research. It quest for new control methods in what concerns forest plant pathogens, with a special emphasis on fungi like organisms of the genus Phytophthora. Species of Phytophthora are the most successful plant pathogens of the moment, affecting forest and agricultural systems worldwide, many of them being invasive alien organisms in many ecosystems. The hyperspace of their ecological niche is defined by hosts, environment and human interference, as main axes. To select most important variables within the hyperspace, is important the understanding of the complex role of pathogens in the ecosystems as well as for control programs. Biotic relationships within ecosystem of host-pathogen couple are depicted by ecological network and specific metrics attached to this. The star shaped network is characterized by few high degree nodes, by short path lengths and relatively low connectivity, premises for a rapid disturbance spread. 

  20. Ecological niche of plant pathogens

    Directory of Open Access Journals (Sweden)

    Ecaterina Fodor

    2011-02-01

    Full Text Available Disease ecology is a new approach to the understanding of the spread and dynamics of pathogens in natural and man-made environments. Defining and describing the ecological niche of the pathogens is one of the major tasks for ecological theory, as well as for practitioners preoccupied with the control and forecasting of established and emerging diseases. Niche theory has been periodically revised, not including in an explicit way the pathogens. However, many progresses have been achieved in niche modeling of disease spread, but few attempts were made to construct a theoretical frame for the ecological niche of pathogens. The paper is a review of the knowledge accumulated during last decades in the niche theory of pathogens and proposes an ecological approach in research. It quest for new control methods in what concerns forest plant pathogens, with a special emphasis on fungi like organisms of the genus Phytophthora. Species of Phytophthora are the most successful plant pathogens of the moment, affecting forest and agricultural systems worldwide, many of them being invasive alien organisms in many ecosystems. The hyperspace of their ecological niche is defined by hosts, environment and human interference, as main axes. To select most important variables within the hyperspace, is important for the understanding of the complex role of pathogens in the ecosystems as well as for control programs. Biotic relationships within ecosystem of host-pathogen couple are depicted by ecological network and specific metrics attached to this. The star shaped network is characterized by few high degree nodes, by short path lengths and relatively low connectivity, premises for a rapid disturbance spread.

  1. Temporal ecology in the Anthropocene.

    Science.gov (United States)

    Wolkovich, E M; Cook, B I; McLauchlan, K K; Davies, T J

    2014-11-01

    Two fundamental axes - space and time - shape ecological systems. Over the last 30 years spatial ecology has developed as an integrative, multidisciplinary science that has improved our understanding of the ecological consequences of habitat fragmentation and loss. We argue that accelerating climate change - the effective manipulation of time by humans - has generated a current need to build an equivalent framework for temporal ecology. Climate change has at once pressed ecologists to understand and predict ecological dynamics in non-stationary environments, while also challenged fundamental assumptions of many concepts, models and approaches. However, similarities between space and time, especially related issues of scaling, provide an outline for improving ecological models and forecasting of temporal dynamics, while the unique attributes of time, particularly its emphasis on events and its singular direction, highlight where new approaches are needed. We emphasise how a renewed, interdisciplinary focus on time would coalesce related concepts, help develop new theories and methods and guide further data collection. The next challenge will be to unite predictive frameworks from spatial and temporal ecology to build robust forecasts of when and where environmental change will pose the largest threats to species and ecosystems, as well as identifying the best opportunities for conservation. © 2014 John Wiley & Sons Ltd/CNRS.

  2. Number theory

    CERN Document Server

    Andrews, George E

    1994-01-01

    Although mathematics majors are usually conversant with number theory by the time they have completed a course in abstract algebra, other undergraduates, especially those in education and the liberal arts, often need a more basic introduction to the topic.In this book the author solves the problem of maintaining the interest of students at both levels by offering a combinatorial approach to elementary number theory. In studying number theory from such a perspective, mathematics majors are spared repetition and provided with new insights, while other students benefit from the consequent simpl

  3. Quasispecies made simple.

    Directory of Open Access Journals (Sweden)

    2005-11-01

    Full Text Available Quasispecies are clouds of genotypes that appear in a population at mutation-selection balance. This concept has recently attracted the attention of virologists, because many RNA viruses appear to generate high levels of genetic variation that may enhance the evolution of drug resistance and immune escape. The literature on these important evolutionary processes is, however, quite challenging. Here we use simple models to link mutation-selection balance theory to the most novel property of quasispecies: the error threshold-a mutation rate below which populations equilibrate in a traditional mutation-selection balance and above which the population experiences an error catastrophe, that is, the loss of the favored genotype through frequent deleterious mutations. These models show that a single fitness landscape may contain multiple, hierarchically organized error thresholds and that an error threshold is affected by the extent of back mutation and redundancy in the genotype-to-phenotype map. Importantly, an error threshold is distinct from an extinction threshold, which is the complete loss of the population through lethal mutations. Based on this framework, we argue that the lethal mutagenesis of a viral infection by mutation-inducing drugs is not a true error catastophe, but is an extinction catastrophe.

  4. Graphic Ecologies

    Directory of Open Access Journals (Sweden)

    Brook Weld Muller

    2014-12-01

    Full Text Available This essay describes strategic approaches to graphic representation associated with critical environmental engagement and that build from the idea of works of architecture as stitches in the ecological fabric of the city. It focuses on the building up of partial or fragmented graphics in order to describe inclusive, open-ended possibilities for making architecture that marry rich experience and responsive performance. An aphoristic approach to crafting drawings involves complex layering, conscious absence and the embracing of tension. A self-critical attitude toward the generation of imagery characterized by the notion of ‘loose precision’ may lead to more transformative and environmentally responsive architectures.

  5. Industrial ecology.

    Science.gov (United States)

    Patel, C K

    1992-01-01

    Industrial ecology addresses issues that will impact future production, use, and disposal technologies; proper use of the concept should reduce significantly the resources devoted to potential remediation in the future. This cradle-to-reincarnation production philosophy includes industrial processes that are environmentally sound and products that are environmentally safe during use and economically recyclable after use without adverse impact on the environment or on the net cost to society. This will require an industry-university-government round table to set the strategy and agenda for progress. PMID:11607254

  6. Crossing simple resonances

    International Nuclear Information System (INIS)

    Collins, T.

    1985-08-01

    A simple criterion governs the beam distortion and/or loss of protons on a fast resonance crossing. Results from numerical integrations are illustrated for simple sextupole, octupole, and 10-pole resonances

  7. Crossing simple resonances

    Energy Technology Data Exchange (ETDEWEB)

    Collins, T.

    1985-08-01

    A simple criterion governs the beam distortion and/or loss of protons on a fast resonance crossing. Results from numerical integrations are illustrated for simple sextupole, octupole, and 10-pole resonances.

  8. Media Ecology

    Directory of Open Access Journals (Sweden)

    Marina Ašković

    2015-05-01

    Full Text Available Does the trend in which electronic media are gradually becoming extension of human body have to move towards full enslavement of a human and his personality, or the same human will unpredictably, with the aid of his personal media literacy, exit the whirls of media and technological censorships? Personality crisis is closely related to the crisis of language no matter how contradicted to global ideology of transnational transhumanism it may seem. Considering the fact that recent media presentations of the world are based on commercialization of environmentalism, philosophical and aesthetic thought appears as an important subject of ecology. As media mediates, the scenery of civilized living increasingly becomes more appealing even though it derives from commercial and political background. Consequently, the future of humanity depends by large on the philosophy of media. Media have to truly ecologise returning the humanum to its essence making it into the extension of the natural world.

  9. Game Theory .net.

    Science.gov (United States)

    Shor, Mikhael

    2003-01-01

    States making game theory relevant and accessible to students is challenging. Describes the primary goal of GameTheory.net is to provide interactive teaching tools. Indicates the site strives to unite educators from economics, political and computer science, and ecology by providing a repository of lecture notes and tests for courses using…

  10. Ecological stability of landscape - ecological infrastructure - ecological management

    International Nuclear Information System (INIS)

    1992-01-01

    The Field Workshop 'Ecological Stability of Landscape - Ecological Infrastructure - Ecological Management' was held within a State Environmental Programme financed by the Federal Committee for the Environment. The objectives of the workshop were to present Czech and Slovak approaches to the ecological stability of the landscape by means of examples of some case studies in the field, and to exchange ideas, theoretical knowledge and practical experience on implementing the concept of ecological infrastructure in landscape management. Out of 19 papers contained in the proceedings, 3 items were inputted to the INIS system. (Z.S.)

  11. Socio-Ecological Innovation

    DEFF Research Database (Denmark)

    Edgeman, Rick; Eskildsen, Jacob Kjær

    Socio‐Ecological Innovation or SEI is innovation resulting from strategic integration of sustainable innovation and innovation for sustainability. In particular SEI is regarded as critical to organizations intent on progressing toward Sustainable Enterprise Excellence (SEE) and, indeed, progressing......, how developed or mature it is, and how future SEI strategy and results can be improved. As an aid to these efforts, non‐prescriptive approaches to SEI are discussed, maturity scale assessment for SEI is developed and discussed, and a simple assessment report that combines graphic and narrative...... feedback is presented. The assessment report is referred to as a SEI News Report and is intended not only to provide feedback to the organization concerning its present SEI performance, but also to deliver significant foresight that will inform future SEI efforts, strengthening the likelihood...

  12. Editorial: Pedagogical Media Ecologies

    Directory of Open Access Journals (Sweden)

    Dorothee M. Meister

    2014-07-01

    briefly introduces the reader to the triangular model used by Bachmair, Pachler and Cook in this issue (and in other publications to analyse the socio-cultural and cognitive possibilities opened up by various mobile media. Sandra Aßmann and Bardo Herzig discuss three theoretical approaches – a network perspective, systems theory and semiotics – in order to conceptualize and analyze learning with media in a range of formal and informal settings. They use the example of «friending» someone via Facebook, a context in which the formal and informal often intersect in unexpected ways. In this way, Aßmann and Herzig demonstrate the manifest complexities of communication analysis and pragmatics in these relatively new networked, mediated contexts. Judith Seipold provides an extensive overview of the burgeoning literature on the use and potential of mobile technologies in learning and educational ecologies. The research perspectives or frameworks covered by Seipold include critical, ethical, resource-centered, learning process-centered as well as ecological frames of reference. In her coverage of the last of these, not only does Seipold help to reframe the theme of this special issue as a whole, she also provides an excellent segue to the ecologically oriented analysis of «mobile learning» that follows. Ben Bachmair and Norbert Pachler’s contribution, «A Cultural Ecological Frame for Mobility and Learning», reflects the work of the London Mobile Learning Group, examining mobile resources and affordances from the ecological perspectives of Gibson, Postman and the seminal German media-pedagogue, Dieter Baacke. Using the structuration theory of Anthony Giddens, Bachmair, Norbert and Cook elaborate the aforementioned triangular model for understanding both the agency and the cultural and structural constraints offered by mobile technologies. In «Building as Interface: Sustainable Educational Ecologies», Suzanne de Castell, Milena Droumeva and Jen Jenson connect

  13. Civic Ecology: A Postmodern Approach to Ecological Sustainability

    Science.gov (United States)

    Lopes, V. L.

    2013-12-01

    Human agency is transforming the planetary processes at unprecedented rates risking damaging essential life-support systems. Climate change, massive species extinction, land degradation, resources depletion, overpopulation, poverty and social injustice are all the result of human choices and non-sustainable ways of life. The survival of our modern economic systems depends upon insatiable consumption - a simple way of life no longer satisfies most people. Detached, instrumental rationality has created an ideal of liberalism based on individual pursuit of self-interest, leading the way into unprecedented material progress but bringing with it human alienation, social injustice, and ecological degradation. The purpose of this presentation is to introduce a community-based systems response to a growing sense that the interlocked social-ecological crisis is as much a problem of human thought and behavior as it is about identifying carrying capacities and CO2 concentrations in the atmosphere. This approach, referred to here as civic ecology, presents a new and important paradigm shift in sustainability practice that attempts to bring together and integrate ecological ideas and postmodern thinking. As such, it is as much a holistic, dynamic, and synergistic approach to ecological sustainability, as it is a philosophy of life and ethical perspective born of ecological understanding and insight. Civic ecology starts with the proposition that the key factor determining the health of the ecosphere is the behavior of human beings, and therefore many of the most important issues related to sustainability lie in the areas of human thought and culture. Thus, the quest for sustainability must include as a central concern the transformation of psychological and behavioral patterns that have become an imminent danger to planetary health. At the core of this understanding is a fundamental paradigm shift from the basic commitments of modern Western culture to its model of mechanism

  14. The ecology of religious beliefs

    Science.gov (United States)

    Botero, Carlos A.; Gardner, Beth; Kirby, Kathryn R.; Bulbulia, Joseph; Gavin, Michael C.; Gray, Russell D.

    2014-01-01

    Although ecological forces are known to shape the expression of sociality across a broad range of biological taxa, their role in shaping human behavior is currently disputed. Both comparative and experimental evidence indicate that beliefs in moralizing high gods promote cooperation among humans, a behavioral attribute known to correlate with environmental harshness in nonhuman animals. Here we combine fine-grained bioclimatic data with the latest statistical tools from ecology and the social sciences to evaluate the potential effects of environmental forces, language history, and culture on the global distribution of belief in moralizing high gods (n = 583 societies). After simultaneously accounting for potential nonindependence among societies because of shared ancestry and cultural diffusion, we find that these beliefs are more prevalent among societies that inhabit poorer environments and are more prone to ecological duress. In addition, we find that these beliefs are more likely in politically complex societies that recognize rights to movable property. Overall, our multimodel inference approach predicts the global distribution of beliefs in moralizing high gods with an accuracy of 91%, and estimates the relative importance of different potential mechanisms by which this spatial pattern may have arisen. The emerging picture is neither one of pure cultural transmission nor of simple ecological determinism, but rather a complex mixture of social, cultural, and environmental influences. Our methods and findings provide a blueprint for how the increasing wealth of ecological, linguistic, and historical data can be leveraged to understand the forces that have shaped the behavior of our own species. PMID:25385605

  15. Singular perturbation of simple eigenvalues

    International Nuclear Information System (INIS)

    Greenlee, W.M.

    1976-01-01

    Two operator theoretic theorems which generalize those of asymptotic regular perturbation theory and which apply to singular perturbation problems are proved. Application of these theorems to concrete problems is involved, but the perturbation expansions for eigenvalues and eigenvectors are developed in terms of solutions of linear operator equations. The method of correctors, as well as traditional boundary layer techniques, can be used to apply these theorems. The current formulation should be applicable to highly singular ''hard core'' potential perturbations of the radial equation of quantum mechanics. The theorems are applied to a comparatively simple model problem whose analysis is basic to that of the quantum mechanical problem

  16. Indigenous Ecological Knowledge and Modern Western Ecological ...

    African Journals Online (AJOL)

    Indigenous knowledge is often dismissed as 'traditional and outdated', and hence irrelevant to modern ecological assessment. This theoretical paper critically examines the arguments advanced to elevate modern western ecological knowledge over indigenous ecological knowledge, as well as the sources and uses of ...

  17. Quantifying chaos for ecological stoichiometry.

    Science.gov (United States)

    Duarte, Jorge; Januário, Cristina; Martins, Nuno; Sardanyés, Josep

    2010-09-01

    The theory of ecological stoichiometry considers ecological interactions among species with different chemical compositions. Both experimental and theoretical investigations have shown the importance of species composition in the outcome of the population dynamics. A recent study of a theoretical three-species food chain model considering stoichiometry [B. Deng and I. Loladze, Chaos 17, 033108 (2007)] shows that coexistence between two consumers predating on the same prey is possible via chaos. In this work we study the topological and dynamical measures of the chaotic attractors found in such a model under ecological relevant parameters. By using the theory of symbolic dynamics, we first compute the topological entropy associated with unimodal Poincaré return maps obtained by Deng and Loladze from a dimension reduction. With this measure we numerically prove chaotic competitive coexistence, which is characterized by positive topological entropy and positive Lyapunov exponents, achieved when the first predator reduces its maximum growth rate, as happens at increasing δ1. However, for higher values of δ1 the dynamics become again stable due to an asymmetric bubble-like bifurcation scenario. We also show that a decrease in the efficiency of the predator sensitive to prey's quality (increasing parameter ζ) stabilizes the dynamics. Finally, we estimate the fractal dimension of the chaotic attractors for the stoichiometric ecological model.

  18. Network spandrels reflect ecological assembly.

    Science.gov (United States)

    Maynard, Daniel S; Serván, Carlos A; Allesina, Stefano

    2018-03-01

    Ecological networks that exhibit stable dynamics should theoretically persist longer than those that fluctuate wildly. Thus, network structures which are over-represented in natural systems are often hypothesised to be either a cause or consequence of ecological stability. Rarely considered, however, is that these network structures can also be by-products of the processes that determine how new species attempt to join the community. Using a simulation approach in tandem with key results from random matrix theory, we illustrate how historical assembly mechanisms alter the structure of ecological networks. We demonstrate that different community assembly scenarios can lead to the emergence of structures that are often interpreted as evidence of 'selection for stability'. However, by controlling for the underlying selection pressures, we show that these assembly artefacts-or spandrels-are completely unrelated to stability or selection, and are instead by-products of how new species are introduced into the system. We propose that these network-assembly spandrels are critically overlooked aspects of network theory and stability analysis, and we illustrate how a failure to adequately account for historical assembly can lead to incorrect inference about the causes and consequences of ecological stability. © 2018 John Wiley & Sons Ltd/CNRS.

  19. Social Ecology and Aesthetic Criticism

    Directory of Open Access Journals (Sweden)

    Owen, Connor

    2016-12-01

    Full Text Available While ecocriticism has become a respected field in literary theory and in the broader landscape of aesthetic philosophy, it could benefit from an enhanced ethical-political framework which social ecology – an underrated critical theory developed by Murray Bookchin – could provide. This essay attempts to tease out the potentials for such a framework, integrating the insights of social ecology, ecocriticism, Critical Realism, and John Dewey's aesthetic concepts into a layered idea-set used for the study of all kinds of aesthetic objects, from popular art to the gallery arts. Its key principles are the emergence of aesthetic objects (including formal artworks out of congealed human experience, the relation between organism and environment in assessing meaning, the breakdown of implicit or overt hierarchies within a work, and the idea of the artist and art-critic as a "gardener".

  20. DECISION STRATEGIES AND COGNITIVE ADAPTATIONS TO ECOLOGY

    Directory of Open Access Journals (Sweden)

    Poleszczuk Jan

    2017-06-01

    Full Text Available In this paper, I discuss the concept of adaptive rationality. I present a simple model of ecology and the set of decision rules. The basic structure of the process of cognitive adaptation to ecology is described as a structure comprising (1 perceptual space, (2 a function valuating perceived items, (3 a set of available decision rules and (4 the adaptation process - identification and selection of the best strategies in given ecological conditions. The presented model of ecosystem allows a conclusion that completely opposite strategies may be compatible with the assumption of adaptive rationality.

  1. Testing theories

    International Nuclear Information System (INIS)

    Casten, R F

    2015-01-01

    This paper discusses some simple issues that arise in testing models, with a focus on models for low energy nuclear structure. By way of simplified examples, we illustrate some dangers in blind statistical assessments, pointing out especially the need to include theoretical uncertainties, the danger of over-weighting precise or physically redundant experimental results, the need to assess competing theories with independent and physically sensitive observables, and the value of statistical tests properly evaluated. (paper)

  2. Interim balance: Ecology. Oekologische Zwischenbilanz

    Energy Technology Data Exchange (ETDEWEB)

    Kogon, E; Jungk, R

    1981-03-01

    The world wide ecology problem is discussed with examples of energy, transportation, chemistry, agriculture and food industry, and water supply. Destruction of nature and human discord is considered. Conservative in our political parties and their views on environmental protection are presented, including alliance between reds and 'greens''. The Rhine initiative is discussed. Lead respects no borders accounts experiences of citizens' action groups in Lothringia and the Saar district. International airport Munich-II/comments by a protestant. 'Give priority to life is hearing on environmental protection. Other subjects include: 'Green's in the Bremen Senate; policy in a hard-hearing world psychology of citizens' action groups; critical ecological research and scientific establishment; full productivity and ecology; the deluge to follow/hints on how to build an ark; symbiosis is more than coexistence/ecologists' social theory; throwing in two hundred elementary particles/on the way to an ecological concept of science; scientific journals; alternative literature; and a teaching model for a teaching subject' ecology'.

  3. Including Overweight or Obese Students in Physical Education: A Social Ecological Constraint Model

    Science.gov (United States)

    Li, Weidong; Rukavina, Paul

    2012-01-01

    In this review, we propose a social ecological constraint model to study inclusion of overweight or obese students in physical education by integrating key concepts and assumptions from ecological constraint theory in motor development and social ecological models in health promotion and behavior. The social ecological constraint model proposes…

  4. Toward Gleasonian landscape ecology: From communities to species, from patches to pixels

    Science.gov (United States)

    Samuel A. Cushman; Jeffrey S. Evans; Kevin McGarigal; Joseph M. Kiesecker

    2010-01-01

    The fusion of individualistic community ecology with the Hutchinsonian niche concept enabled a broad integration of ecological theory, spanning all the way from the niche characteristics of individual species, to the composition, structure, and dynamics of ecological communities. Landscape ecology has been variously described as the study of the structure, function,...

  5. The merits of neutral theory

    NARCIS (Netherlands)

    Alonso, D.; Etienne, R.S.; McKane, A.J.

    2006-01-01

    Hubbell's neutral theory of biodiversity has challenged the classic niche-based view of ecological community structure. Although there have been many attempts to falsify Hubbell's theory, we argue that falsification should not lead to rejection, because there is more to the theory than neutrality

  6. A rewriting view of simple typing

    NARCIS (Netherlands)

    Stump, A.; Zantema, H.; Kimmell, G.; El Haj Omar, R.

    2013-01-01

    This paper shows how a recently developed view of typing as small-step abstract reduction, due to Kuan, MacQueen, and Findler, can be used to recast the development of simple type theory from a rewriting perspective. We show how standard meta-theoretic results can be proved in a completely new way,

  7. A rewriting view of simple typing

    NARCIS (Netherlands)

    Stump, A.; Zantema, H.; Kimmell, G.; El Haj Omar, R.

    2012-01-01

    This paper shows how a recently developed view of typing as small-step abstract reduction, due to Kuan, MacQueen, and Findler, can be used to recast the development of simple type theory from a rewriting perspective. We show how standard meta-theoretic results can be proved in a completely new way,

  8. Could information theory provide an ecological theory of sensory processing?

    Science.gov (United States)

    Atick, Joseph J

    2011-01-01

    The sensory pathways of animals are well adapted to processing a special class of signals, namely stimuli from the animal's environment. An important fact about natural stimuli is that they are typically very redundant and hence the sampled representation of these signals formed by the array of sensory cells is inefficient. One could argue for some animals and pathways, as we do in this review, that efficiency of information representation in the nervous system has several evolutionary advantages. Consequently, one might expect that much of the processing in the early levels of these sensory pathways could be dedicated towards recoding incoming signals into a more efficient form. In this review, we explore the principle of efficiency of information representation as a design principle for sensory processing. We give a preliminary discussion on how this principle could be applied in general to predict neural processing and then discuss concretely some neural systems where it recently has been shown to be successful. In particular, we examine the fly's LMC coding strategy and the mammalian retinal coding in the spatial, temporal and chromatic domains.

  9. How superdiffusion gets arrested: Ecological encounters explain shift from Lévy to Brownian movement

    NARCIS (Netherlands)

    De Jager, M.; Bartumeus, F.; Kölzsch, A.; Weissing, F.J.; Hengeveld, G.M.; Nolet, B.A.; Herman, P.M.J.; Van de Koppel, J.

    2014-01-01

    Ecological theory uses Brownian motion as a default template for describing ecological movement, despite limited mechanistic underpinning. The generality of Brownian motion has recently been challenged by empirical studies that highlight alternative movement patterns of animals, especially when

  10. How superdiffusion gets arrested: ecological encounters explain shift from Levy to Brownian movement

    NARCIS (Netherlands)

    de Jager, M.; Bartumeus, F.; Kölzsch, A.; Weissing, F.J.; Hengeveld, G.M.; Nolet, B.A.; Herman, P.M.J.; de Koppel, J.

    2014-01-01

    Ecological theory uses Brownian motion as a default template for describing ecological movement, despite limited mechanistic underpinning. The generality of Brownian motion has recently been challenged by empirical studies that highlight alternative movement patterns of animals, especially when

  11. How superdiffusion gets arrested: ecological encounters explain shift from Lévy to Brownian movement

    NARCIS (Netherlands)

    Jager, de M.; Bartumeus, F.; Kölzsch, A.; Weissing, F.J.; Hengeveld, G.M.; Nolet, B.A.; Herman, P.M.J.; Koppel, van de J.

    2014-01-01

    Ecological theory uses Brownian motion as a default template for describing ecological movement, despite limited mechanistic underpinning. The generality of Brownian motion has recently been challenged by empirical studies that highlight alternative movement patterns of animals, especially when

  12. Integrated approaches to long-term studies of urban ecological systems

    Science.gov (United States)

    Nancy B. Grimm; J. Morgan Grove; Steward T.A. Pickett; Charles L. Redman

    2000-01-01

    Urban ecological systems present multiple challenges to ecologists—pervasive human impact and extreme heterogeneity of cities, and the need to integrate social and ecological approaches, concepts, and theory.

  13. How superdiffusion gets arrested : ecological encounters explain shift from Levy to Brownian movement

    NARCIS (Netherlands)

    de Jager, Monique; Bartumeus, Frederic; Kolzsch, Andrea; Weissing, Franz J.; Hengeveld, Geerten M.; Nolet, Bart A.; Herman, Peter M. J.; de Koppel, Johan van

    2014-01-01

    Ecological theory uses Brownian motion as a default template for describing ecological movement, despite limited mechanistic underpinning. The generality of Brownian motion has recently been challenged by empirical studies that highlight alternative movement patterns of animals, especially when

  14. How superdiffusion gets arrested : Ecological encounters explain shift from Levy to Brownian movement

    NARCIS (Netherlands)

    de Jager, Monique; Bartumeus, Frederic; Kölzsch, Andrea; Weissing, Franz J.; Hengeveld, Geerten M.; Nolet, Bart A.; Herman, Peter M.J.; van de Koppel, Johan

    2014-01-01

    Ecological theory uses Brownian motion as a default template for describing ecological movement, despite limited mechanistic underpinning. The generality of Brownian motion has recently been challenged by empirical studies that highlight alternative movement patterns of animals, especially when

  15. Ecological units: definitions and application.

    Science.gov (United States)

    Jax, Kurt

    2006-09-01

    Concepts of ecological units, such as population, community, and ecosystem, are at the basis of ecological theory and research and have increasingly become the focus of conservation strategies. Concepts of these units still suffer from inconsistencies and confusions over terminology. The different concepts are treated here together as a common "conceptual cluster," with similar ecological functions (roles) and similar problems in their definition and use. An analysis of the multitude of existing terms and concepts that have been developed for these units reveals that they differ with respect to at least four basic criteria: (i) the questions as to whether they are defined statistically or via a network of interactions; (ii) if their boundaries are drawn by topographical or process-related criteria; (iii) how high the required internal relationships are; and (iv) if they are perceived as "real" entities or abstractions by an observer The various definitions cannot be easily sorted into just a few types, but they can be characterized by several independent criteria. I argue that serious problems arise if the different possibilities of defining ecological units are not recognized and if the concepts are perceived as self-evident. The different concepts of ecological units should be defined and used in a philosophically informed manner I propose a dual approach to the use of ecological units. Generic meanings of the main concepts (especially population, community, and ecosystem) should be retained only as heuristically useful perspectives, while specific and "operational" definitions of the concepts as units should be developed, depending on specific purposes of their use. Some thoughts on the basic requirements for such definitions and the domains of their uses are briefly explained.

  16. Vocabulary of CPH Theory and Modern Physics

    DEFF Research Database (Denmark)

    Javadi, Hossein; Forouzbakhsh, Farshid; Daei Kasmaei, Hamed

    2016-01-01

    Wherefore CPH theory was presented? There are various theories in physics, but nature is unique. This is not nature's problem that we have various theories; nature obeys simple and unique law. So, we should improve our understanding of physical phenomena and unify theories. There is a compare brief...... of CPH Theory (Creative Particles of Higgs Theory) and modern physics in this vocabulary....

  17. Strategy as simple rules.

    Science.gov (United States)

    Eisenhardt, K M; Sull, D N

    2001-01-01

    The success of Yahoo!, eBay, Enron, and other companies that have become adept at morphing to meet the demands of changing markets can't be explained using traditional thinking about competitive strategy. These companies have succeeded by pursuing constantly evolving strategies in market spaces that were considered unattractive according to traditional measures. In this article--the third in an HBR series by Kathleen Eisenhardt and Donald Sull on strategy in the new economy--the authors ask, what are the sources of competitive advantage in high-velocity markets? The secret, they say, is strategy as simple rules. The companies know that the greatest opportunities for competitive advantage lie in market confusion, but they recognize the need for a few crucial strategic processes and a few simple rules. In traditional strategy, advantage comes from exploiting resources or stable market positions. In strategy as simple rules, advantage comes from successfully seizing fleeting opportunities. Key strategic processes, such as product innovation, partnering, or spinout creation, place the company where the flow of opportunities is greatest. Simple rules then provide the guidelines within which managers can pursue such opportunities. Simple rules, which grow out of experience, fall into five broad categories: how- to rules, boundary conditions, priority rules, timing rules, and exit rules. Companies with simple-rules strategies must follow the rules religiously and avoid the temptation to change them too frequently. A consistent strategy helps managers sort through opportunities and gain short-term advantage by exploiting the attractive ones. In stable markets, managers rely on complicated strategies built on detailed predictions of the future. But when business is complicated, strategy should be simple.

  18. Culturally compelling strategies for behaviour change: a social ecology model and case study in malaria prevention.

    Science.gov (United States)

    Panter-Brick, Catherine; Clarke, Sian E; Lomas, Heather; Pinder, Margaret; Lindsay, Steve W

    2006-06-01

    Behaviour change is notoriously difficult to initiate and sustain, and the reasons why efforts to promote healthy behaviours fail are coming under increasing scrutiny. To be successful, health interventions should build on existing practices, skills and priorities, recognise the constraints on human behaviour, and either feature community mobilisation or target those most receptive to change. Furthermore, interventions should strive to be culturally compelling, not merely culturally appropriate: they must engage local communities and nestle within social and ecological landscapes. In this paper, we propose a social ecology perspective to make explicit the links between intention to change, actual behaviour change, and subsequent health impact, as relating to both theory-based models and practical strategies for triggering behaviour change. A social ecology model focuses attention on the contexts of behaviour when designing, implementing or critically evaluating interventions. As a case study, we reflect on a community-directed intervention in rural Gambia designed to reduce malaria by promoting a relatively simple and low-cost behaviour: repairing holes in mosquito bednets. In phase 1, contextual information on bednet usage, transactions and repairs (the 'social lives' of nets) was documented. In phase 2 (intervention), songs were composed and posters displayed by community members to encourage repairs, creating a sense of ownership and a compelling medium for the transmission of health messages. In phase 3 (evaluation), qualitative and quantitative data showed that household responses were particularly rapid and extensive, with significant increase in bednet repairs (psocial ecology-of behaviour practices that are the bedrock of health interventions.

  19. Modeling reproductive decisions with simple heuristics

    Directory of Open Access Journals (Sweden)

    Peter Todd

    2013-10-01

    Full Text Available BACKGROUND Many of the reproductive decisions that humans make happen without much planning or forethought, arising instead through the use of simple choice rules or heuristics that involve relatively little information and processing. Nonetheless, these heuristic-guided decisions are typically beneficial, owing to humans' ecological rationality - the evolved fit between our constrained decision mechanisms and the adaptive problems we face. OBJECTIVE This paper reviews research on the ecological rationality of human decision making in the domain of reproduction, showing how fertility-related decisions are commonly made using various simple heuristics matched to the structure of the environment in which they are applied, rather than being made with information-hungry mechanisms based on optimization or rational economic choice. METHODS First, heuristics for sequential mate search are covered; these heuristics determine when to stop the process of mate search by deciding that a good-enough mate who is also mutually interested has been found, using a process of aspiration-level setting and assessing. These models are tested via computer simulation and comparison to demographic age-at-first-marriage data. Next, a heuristic process of feature-based mate comparison and choice is discussed, in which mate choices are determined by a simple process of feature-matching with relaxing standards over time. Parental investment heuristics used to divide resources among offspring are summarized. Finally, methods for testing the use of such mate choice heuristics in a specific population over time are then described.

  20. Simple types of anisotropic inflation

    International Nuclear Information System (INIS)

    Barrow, John D.; Hervik, Sigbjoern

    2010-01-01

    We display some simple cosmological solutions of gravity theories with quadratic Ricci curvature terms added to the Einstein-Hilbert Lagrangian which exhibit anisotropic inflation. The Hubble expansion rates are constant and unequal in three orthogonal directions. We describe the evolution of the simplest of these homogeneous and anisotropic cosmological models from its natural initial state and evaluate the deviations they will create from statistical isotropy in the fluctuations produced during a period of anisotropic inflation. The anisotropic inflation is not a late-time attractor in these models but the rate of approach to a final isotropic de Sitter state is slow and is conducive to the creation of observable anisotropic statistical effects in the microwave background. The statistical anisotropy would not be scale invariant and the level of statistical anisotropy will grow with scale.

  1. Diversity spurs diversification in ecological communities.

    Science.gov (United States)

    Calcagno, Vincent; Jarne, Philippe; Loreau, Michel; Mouquet, Nicolas; David, Patrice

    2017-06-09

    Diversity is a fundamental, yet threatened, property of ecological systems. The idea that diversity can itself favour diversification, in an autocatalytic process, is very appealing but remains controversial. Here, we study a generalized model of ecological communities and investigate how the level of initial diversity influences the possibility of evolutionary diversification. We show that even simple models of intra- and inter-specific ecological interactions can predict a positive effect of diversity on diversification: adaptive radiations may require a threshold number of species before kicking-off. We call this phenomenon DDAR (diversity-dependent adaptive radiations) and identify mathematically two distinct pathways connecting diversity to diversification, involving character displacement and the positive diversity-productivity relationship. Our results may explain observed delays in adaptive radiations at the macroscale and diversification patterns reported in experimental microbial communities, and shed new light on the dynamics of ecological diversity, the diversity-dependence of diversification rates, and the consequences of biodiversity loss.

  2. Diversity spurs diversification in ecological communities

    Science.gov (United States)

    Calcagno, Vincent; Jarne, Philippe; Loreau, Michel; Mouquet, Nicolas; David, Patrice

    2017-06-01

    Diversity is a fundamental, yet threatened, property of ecological systems. The idea that diversity can itself favour diversification, in an autocatalytic process, is very appealing but remains controversial. Here, we study a generalized model of ecological communities and investigate how the level of initial diversity influences the possibility of evolutionary diversification. We show that even simple models of intra- and inter-specific ecological interactions can predict a positive effect of diversity on diversification: adaptive radiations may require a threshold number of species before kicking-off. We call this phenomenon DDAR (diversity-dependent adaptive radiations) and identify mathematically two distinct pathways connecting diversity to diversification, involving character displacement and the positive diversity-productivity relationship. Our results may explain observed delays in adaptive radiations at the macroscale and diversification patterns reported in experimental microbial communities, and shed new light on the dynamics of ecological diversity, the diversity-dependence of diversification rates, and the consequences of biodiversity loss.

  3. Simple Finite Sums

    KAUST Repository

    Alabdulmohsin, Ibrahim M.

    2018-03-07

    We will begin our treatment of summability calculus by analyzing what will be referred to, throughout this book, as simple finite sums. Even though the results of this chapter are particular cases of the more general results presented in later chapters, they are important to start with for a few reasons. First, this chapter serves as an excellent introduction to what summability calculus can markedly accomplish. Second, simple finite sums are encountered more often and, hence, they deserve special treatment. Third, the results presented in this chapter for simple finite sums will, themselves, be used as building blocks for deriving the most general results in subsequent chapters. Among others, we establish that fractional finite sums are well-defined mathematical objects and show how various identities related to the Euler constant as well as the Riemann zeta function can actually be derived in an elementary manner using fractional finite sums.

  4. Simple Finite Sums

    KAUST Repository

    Alabdulmohsin, Ibrahim M.

    2018-01-01

    We will begin our treatment of summability calculus by analyzing what will be referred to, throughout this book, as simple finite sums. Even though the results of this chapter are particular cases of the more general results presented in later chapters, they are important to start with for a few reasons. First, this chapter serves as an excellent introduction to what summability calculus can markedly accomplish. Second, simple finite sums are encountered more often and, hence, they deserve special treatment. Third, the results presented in this chapter for simple finite sums will, themselves, be used as building blocks for deriving the most general results in subsequent chapters. Among others, we establish that fractional finite sums are well-defined mathematical objects and show how various identities related to the Euler constant as well as the Riemann zeta function can actually be derived in an elementary manner using fractional finite sums.

  5. Ecologies of Learning, Ecologies of Creativity

    DEFF Research Database (Denmark)

    Høyrup, Helene

    in the light of the new Danish school reform. How can different learning institutions contribute to a “joint” ecology of learning? What would the benefits be from this in terms of young people’s literacies? On what theoretical basis can such an ecology and co-creation take place? And what kind of didactics...

  6. Excel 2010 Made Simple

    CERN Document Server

    Katz, Abbott

    2011-01-01

    Get the most out of Excel 2010 with Excel 2010 Made Simple - learn the key features, understand what's new, and utilize dozens of time-saving tips and tricks to get your job done. Over 500 screen visuals and clear-cut instructions guide you through the features of Excel 2010, from formulas and charts to navigating around a worksheet and understanding Visual Basic for Applications (VBA) and macros. Excel 2010 Made Simple takes a practical and highly effective approach to using Excel 2010, showing you the best way to complete your most common spreadsheet tasks. You'll learn how to input, format,

  7. Droids Made Simple

    CERN Document Server

    Mazo, Gary

    2011-01-01

    If you have a Droid series smartphone - Droid, Droid X, Droid 2, or Droid 2 Global - and are eager to get the most out of your device, Droids Made Simple is perfect for you. Authors Martin Trautschold, Gary Mazo and Marziah Karch guide you through all of the features, tips, and tricks using their proven combination of clear instructions and detailed visuals. With hundreds of annotated screenshots and step-by-step directions, Droids Made Simple will transform you into a Droid expert, improving your productivity, and most importantly, helping you take advantage of all of the cool features that c

  8. Clusters in simple fluids

    International Nuclear Information System (INIS)

    Sator, N.

    2003-01-01

    This article concerns the correspondence between thermodynamics and the morphology of simple fluids in terms of clusters. Definitions of clusters providing a geometric interpretation of the liquid-gas phase transition are reviewed with an eye to establishing their physical relevance. The author emphasizes their main features and basic hypotheses, and shows how these definitions lead to a recent approach based on self-bound clusters. Although theoretical, this tutorial review is also addressed to readers interested in experimental aspects of clustering in simple fluids

  9. Association "Les Simples"

    OpenAIRE

    Thouzery, Michel

    2014-01-01

    Fondée par les producteurs du Syndicat Inter-Massifs pour la Production et l’Économie des Simples (S.I.M.P.L.E.S), l’association base son action sur la recherche et le maintien d’une production de qualité (herboristerie et préparations à base de plantes) qui prend en compte le respect de l’environnement et la pérennité des petits producteurs en zone de montagne. Actions de formation Stages de découverte de la flore médicinale sauvage, Stages de culture et transformation des plantes médicinale...

  10. A simple electron multiplexer

    International Nuclear Information System (INIS)

    Dobrzynski, L; Akjouj, A; Djafari-Rouhani, B; Al-Wahsh, H; Zielinski, P

    2003-01-01

    We present a simple multiplexing device made of two atomic chains coupled by two other transition metal atoms. We show that this simple atomic device can transfer electrons at a given energy from one wire to the other, leaving all other electron states unaffected. Closed-form relations between the transmission coefficients and the inter-atomic distances are given to optimize the desired directional electron ejection. Such devices can be adsorbed on insulating substrates and characterized by current surface technologies. (letter to the editor)

  11. ENVIRONMENTAL PHILOSOPHY AND ECOLOGICAL CULTURE

    Directory of Open Access Journals (Sweden)

    Kalimat M. Alilova

    2017-01-01

    Full Text Available Aim. The aim of the research is to study environmental problems related to the decline of culture, the importance of philosophy in overcoming private and personal interests as well as the unilateral approach of man in his relationship to nature. The study shows how philosophy can participate in the formation of ecological culture, a new ecological consciousness in man, while ecological culture is called upon to resist technocratic stereotypes and the course of history was aimed at preventing the biosphere from becoming deserted. Discussion. On the basis of the analysis of literary sources, we used the method of socio-cultural and socio-natural approaches based on the possibility of philosophy to introduce a new life into culture, new ecological values and new ecological principles. To solve these problems, environmental philosophy develops new theories. Representatives of different cultures, ethnic groups, nations, religions must learn to coexist with each other. We consider philosophy as a means of teaching rapprochement between peoples and creating new opportunities for understanding and improving the environmental situation. Cultural development makes it possible to assess the level of a man’s knowledge of nature, himself and the world around him. Ecological culture is a way of connecting man with nature on the basis of deeper knowledge and understanding. Philosophy says that you cannot move away from nature and be lauded over it since this will destroy culture. Rational doctrines tend to put a person above other living beings so the synthesis of philosophy with culture can have a positive ecological meaning. Conclusion. The findings obtained can be recommended for practical use in schools, starting from primary school, as well as in secondary special educational institutions and universities. It is necessary to work on the motivation and values of people, develop a common and ecological culture. Only a cultured person can move from

  12. Taoism and Deep Ecology.

    Science.gov (United States)

    Sylvan, Richard; Bennett, David

    1988-01-01

    Contrasted are the philosophies of Deep Ecology and ancient Chinese. Discusses the cosmology, morality, lifestyle, views of power, politics, and environmental philosophies of each. Concludes that Deep Ecology could gain much from Taoism. (CW)

  13. Information Assurance Cyber Ecology

    National Research Council Canada - National Science Library

    Jorgensen, Jane

    2003-01-01

    .... The goals of the Cyber Ecology project were to: (1) enable and demonstrate the discovery of noel IA technologies for the detection and mitigation of damage due to cyber attack through the application of ecological models, (2...

  14. Forest Fire Ecology.

    Science.gov (United States)

    Zucca, Carol; And Others

    1995-01-01

    Presents a model that integrates high school science with the needs of the local scientific community. Describes how a high school ecology class conducted scientific research in fire ecology that benefited the students and a state park forest ecologist. (MKR)

  15. Introduction to string theory

    CERN Multimedia

    CERN. Geneva. Audiovisual Unit

    2002-01-01

    I will present a simple and non-technical overview of string theory, aimed for non-experts who like to get some idea what string theory is about. Besides introductory material, I intend to cover also some of the more recent developments.

  16. Simple Driving Techniques

    DEFF Research Database (Denmark)

    Rosendahl, Mads

    2002-01-01

    -like language. Our aim is to extract a simple notion of driving and show that even in this tamed form it has much of the power of more general notions of driving. Our driving technique may be used to simplify functional programs which use function composition and will often be able to remove intermediate data...

  17. A Simple Tiltmeter

    Science.gov (United States)

    Dix, M. G.; Harrison, D. R.; Edwards, T. M.

    1982-01-01

    Bubble vial with external aluminum-foil electrodes is sensing element for simple indicating tiltmeter. To measure bubble displacement, bridge circuit detects difference in capacitance between two sensing electrodes and reference electrode. Tiltmeter was developed for experiment on forecasting seismic events by changes in Earth's magnetic field.

  18. A Simple Hydrogen Electrode

    Science.gov (United States)

    Eggen, Per-Odd

    2009-01-01

    This article describes the construction of an inexpensive, robust, and simple hydrogen electrode, as well as the use of this electrode to measure "standard" potentials. In the experiment described here the students can measure the reduction potentials of metal-metal ion pairs directly, without using a secondary reference electrode. Measurements…

  19. Structure of simple liquids

    International Nuclear Information System (INIS)

    Blain, J.F.

    1969-01-01

    The results obtained by application to argon and sodium of the two important methods of studying the structure of liquids: scattering of X-rays and neutrons, are presented on one hand. On the other hand the principal models employed for reconstituting the structure of simple liquids are exposed: mathematical models, lattice models and their derived models, experimental models. (author) [fr

  20. Simple mathematical fireworks

    International Nuclear Information System (INIS)

    De Luca, R; Faella, O

    2014-01-01

    Mathematical fireworks are reproduced in two dimensions by means of simple notions in kinematics and Newtonian mechanics. Extension of the analysis in three dimensions is proposed and the geometric figures the falling tiny particles make on the ground after explosion are determined. (paper)

  1. simple sequence repeat (SSR)

    African Journals Online (AJOL)

    In the present study, 78 mapped simple sequence repeat (SSR) markers representing 11 linkage groups of adzuki bean were evaluated for transferability to mungbean and related Vigna spp. 41 markers amplified characteristic bands in at least one Vigna species. The transferability percentage across the genotypes ranged ...

  2. A Simple Wave Driver

    Science.gov (United States)

    Temiz, Burak Kagan; Yavuz, Ahmet

    2015-01-01

    This study was done to develop a simple and inexpensive wave driver that can be used in experiments on string waves. The wave driver was made using a battery-operated toy car, and the apparatus can be used to produce string waves at a fixed frequency. The working principle of the apparatus is as follows: shortly after the car is turned on, the…

  3. Quantification of ecological debt

    International Nuclear Information System (INIS)

    Martinez Alier, Joan

    2005-01-01

    The discussion about ecological debt is important keeping in mind historical foreign trade, where natural resources exploitation and primary production exported didn't assessment the ecological damage or the environmental values of the interchange. This essay shows the debate of ecological debt on greenhouse emission, enterprise environmental debit, unequal international trade, toxic waste export, and b io piracy ; in order to present the necessity of a new ecological and equitable world economy

  4. Ecological restoration [book review

    Science.gov (United States)

    Eric J. Gustafson

    2010-01-01

    Ecological restoration has increased in prominence in recent years as environmental policies have slowed the rate of environmental degradation in many parts of the world and practitioners have looked for active ways to reverse the damage. Because of the vast number of types and contexts of degraded ecological systems, the field of ecological restoration is still very...

  5. Two point function for a simple general relativistic quantum model

    OpenAIRE

    Colosi, Daniele

    2007-01-01

    We study the quantum theory of a simple general relativistic quantum model of two coupled harmonic oscillators and compute the two-point function following a proposal first introduced in the context of loop quantum gravity.

  6. Simple form for the Gaussian equations in curved space

    International Nuclear Information System (INIS)

    Mazzitelli, F.D.; Paz, J.P.

    1988-01-01

    We show that the variational Gaussian equations for λphi 4 theory in an arbitrary background gravitational field admit a simple form, which allows the use of a Schwinger-DeWitt-type expansion in order to renormalize them

  7. Beyond Simple Classifications

    DEFF Research Database (Denmark)

    Kautz, Karlheinz

    2012-01-01

    Contemporary Information Systems Development (ISD) takes place in a dynamic environment and is generally acknowledged as a complex activity. We investigate whether complex adaptive systems (CAS) theory is relevant as a theoretical foundation for understanding ISD, and if so, what kind of conception...... in general, beyond any particular development approach chosen for the execution of a project such as agile development. Thereby, we contribute to a complexity theory of ISD. Second, we back up our argument with a coherent empirical account of contemporary ISD, and thus contribute with practical advice...... can be achieved by utilizing the theory? We introduce key CAS concepts and describe an emergent method framework for understanding ISD. Extending existing research, our main contribution is twofold: We first show how CAS and CAS principles are advantageous for comprehending and organizing ISD...

  8. Ecological risks of biological control agents: impacts on IPM

    NARCIS (Netherlands)

    Hokkanen, H.M.T.; Lenteren, van J.C.; Menzler-Hokkanen, I.

    2007-01-01

    Since the early days of integrated pest management a sound ecological foundation has been considered essential for the development of effective systems. From time to time, there have been attempts to evaluate the ways in which ecological theory is exploited in pest control, and to review the lessons

  9. Disturbance ecology and forest management: A review of the literature

    Science.gov (United States)

    Paul Rogers

    1996-01-01

    This review of the disturbance ecology literature, and how it pertains to forest management, is a resource for forest managers and researchers interested in disturbance theory, specific disturbance agents, their interactions, and appropriate methods of inquiry for specific geographic regions. Implications for the future of disturbance ecology-based management are...

  10. Evolutionary and Ecological Consequences of Interspecific Hybridization in Cladocerans

    NARCIS (Netherlands)

    Schwenk, K.; Spaak, P.

    1995-01-01

    The evolutionary process of interspecific hybridization in cladocerans is reviewed based on ecological and population genetic data. The evolutionary consequences of hybridization, biogeographic patterns and fitness comparisons are analyzed within the conceptual framework of theories on

  11. Walter Isard's Contributions to Environmental Economics and Ecological Economics

    NARCIS (Netherlands)

    Rose, Adam; Folmer, Henk; Nijkamp, Peter

    This article summarizes Walter Isard's important contributions to environmental economics and ecological economics. The former is the traditional field that incorporates some limited aspects of the environment into neoclassical economic theory, while the latter is a more comprehensive integration of

  12. Gauge Theories of Vector Particles

    Science.gov (United States)

    Glashow, S. L.; Gell-Mann, M.

    1961-04-24

    The possibility of generalizing the Yang-Mills trick is examined. Thus we seek theories of vector bosons invariant under continuous groups of coordinate-dependent linear transformations. All such theories may be expressed as superpositions of certain "simple" theories; we show that each "simple theory is associated with a simple Lie algebra. We may introduce mass terms for the vector bosons at the price of destroying the gauge-invariance for coordinate-dependent gauge functions. The theories corresponding to three particular simple Lie algebras - those which admit precisely two commuting quantum numbers - are examined in some detail as examples. One of them might play a role in the physics of the strong interactions if there is an underlying super-symmetry, transcending charge independence, that is badly broken. The intermediate vector boson theory of weak interactions is discussed also. The so-called "schizon" model cannot be made to conform to the requirements of partial gauge-invariance.

  13. Climatic ecology of charismatic leadership ideals

    NARCIS (Netherlands)

    van de Vliert, Evert

    2006-01-01

    On the basis of the ecological leadership theory (van de Vliert & Smith, 2004), the perceived effectiveness of charismatic leadership in a country's organizations is conceptualized as an adaptation to two interacting characteristics of the environment-cold, temperate, or hot climate, and national

  14. Aesthetic Engagement, Ecosophy C, and Ecological Appreciation

    Directory of Open Access Journals (Sweden)

    Cheng Xiangzhan

    2013-01-01

    Full Text Available With the aim of healing the earth and sustain a healthy ecosystem for all life forms, not humankind alone, ecoaesthetics emerges as a critique of Enlightenment mentality and of modern aesthetics as it is embodied in it. This mentality contributes greatly to the global ecological crisis and to other problem areas, such as population, economic, political and religious ones. In my understanding of aesthetics, ecoaesthetics is defined as the theory of ecological aesthetic appreciation.[1] With ecoaesthetics as my research horizon, there are at least two reasons for me to pay special attention to American philosopher Arnold Berleant’s conception of aesthetic engagement and his aesthetic theory based on it, an aesthetics of engagement. The first is our shared theme, which is the critique of modern aesthetics. The second reason is more complex for it involves the crucial question of the proper manner of aesthetic appreciation. From the perspective of ecoaesthetics, the contemplation of objects by a separated perceiver, an approach that is based on the modern philosophical dualism of subject and object, is unsatisfactory and inadequate. Berleant’s aesthetic engagement is a more satisfactory account of appreciation that is aesthetic and ecological. This emphasizes the ecological continuity or interrelatedness between the human appreciator and objects. Of course, any theory can occasion critique and development. Based on Berleant’s idea of aesthetic engagement, I would like to propose Ecosophy C. This can be contrasted with Ecosophy T proposed by the Norwegian, Arne Naess, and with traditional Chinese aesthetic wisdom. In contrast with these, I would like to develop my own view of ecological understanding. In order to construct a more comprehensive and reasonable ecoaesthetics, my Ecosophy C contains eight points that are crucial in building an ecological model of aesthetic appreciation for this period of ecological crisis.

  15. Introduction: Affective Ecologies and Conservation

    Directory of Open Access Journals (Sweden)

    Neera M Singh

    2018-01-01

    Full Text Available Engaging the affective and materialist turn in the social sciences, this special section elaborates on how analytical attention on affect and affective relations is central to understanding human-nature relations and to conservation interventions. The contributors to this section use conceptual resources from affect theory, new materialism, and indigenous ontologies to illustrate the practical significance of paying attention to affect in understanding nature-society relations. This introduction reviews these conceptual resources to make a case for affective political ecology.

  16. Complexity is simple!

    Science.gov (United States)

    Cottrell, William; Montero, Miguel

    2018-02-01

    In this note we investigate the role of Lloyd's computational bound in holographic complexity. Our goal is to translate the assumptions behind Lloyd's proof into the bulk language. In particular, we discuss the distinction between orthogonalizing and `simple' gates and argue that these notions are useful for diagnosing holographic complexity. We show that large black holes constructed from series circuits necessarily employ simple gates, and thus do not satisfy Lloyd's assumptions. We also estimate the degree of parallel processing required in this case for elementary gates to orthogonalize. Finally, we show that for small black holes at fixed chemical potential, the orthogonalization condition is satisfied near the phase transition, supporting a possible argument for the Weak Gravity Conjecture first advocated in [1].

  17. Unicameral (simple) bone cysts.

    Science.gov (United States)

    Baig, Rafath; Eady, John L

    2006-09-01

    Since their original description by Virchow, simple bone cysts have been studied repeatedly. Although these defects are not true neoplasms, simple bone cysts may create major structural defects of the humerus, femur, and os calcis. They are commonly discovered incidentally when x-rays are taken for other reasons or on presentation due to a pathologic fracture. Various treatment strategies have been employed, but the only reliable predictor of success of any treatment strategy is the age of the patient; those being older than 10 years of age heal their cysts at a higher rate than those under age 10. The goal of management is the formation of a bone that can withstand the stresses of use by the patient without evidence of continued bone destruction as determined by serial radiographic follow-up. The goal is not a normal-appearing x-ray, but a functionally stable bone.

  18. Information technology made simple

    CERN Document Server

    Carter, Roger

    1991-01-01

    Information Technology: Made Simple covers the full range of information technology topics, including more traditional subjects such as programming languages, data processing, and systems analysis. The book discusses information revolution, including topics about microchips, information processing operations, analog and digital systems, information processing system, and systems analysis. The text also describes computers, computer hardware, microprocessors, and microcomputers. The peripheral devices connected to the central processing unit; the main types of system software; application soft

  19. Modern mathematics made simple

    CERN Document Server

    Murphy, Patrick

    1982-01-01

    Modern Mathematics: Made Simple presents topics in modern mathematics, from elementary mathematical logic and switching circuits to multibase arithmetic and finite systems. Sets and relations, vectors and matrices, tesselations, and linear programming are also discussed.Comprised of 12 chapters, this book begins with an introduction to sets and basic operations on sets, as well as solving problems with Venn diagrams. The discussion then turns to elementary mathematical logic, with emphasis on inductive and deductive reasoning; conjunctions and disjunctions; compound statements and conditional

  20. Ecology and man's environment

    Energy Technology Data Exchange (ETDEWEB)

    Al-Naqeeb, R

    1975-01-01

    A new and exciting discipline of human ecology is in the making. It has not, perhaps fortunately, found its bearings yet and remains to date overly dependent upon the limitations of sociology, biology, engineering and the sciences for its general theory, approaches, and philosophy. A new discipline with a world view and focussed on the human being and his habitat will hopefully emerge from a rich dialectic among scientists, humanists and policy makers educated and experienced in a variety of fields and committed to man's welfare. This new discipline and its practitioner must always be open to the revelations their knowledge will bring to man through the environmental processes. The implications of public policy, science and technology of industrial and post-industrial nations are all in need of considered re-examination by us all. Since their early application in these western societies we have witnessed the general downgrading of the world's environment. An ungrading in social priorities for the development of adequate housing, jobs, medical care and education which is almost always lower in rank than they should be is needed. The role of local groups, involving a well-informed and participating citizenship, in this process of changing priorities will always remain of prime importance, but no long-range goal in a rapidly-changing landscape is possible without broad national and local planning which contains ways and means of implementation.

  1. Philosophy of ecology

    CERN Document Server

    Brown, Bryson; Peacock, Kent A

    2011-01-01

    The most pressing problems facing humanity today - over-population, energy shortages, climate change, soil erosion, species extinctions, the risk of epidemic disease, the threat of warfare that could destroy all the hard-won gains of civilization, and even the recent fibrillations of the stock market - are all ecological or have a large ecological component. in this volume philosophers turn their attention to understanding the science of ecology and its huge implications for the human project. To get the application of ecology to policy or other practical concerns right, humanity needs a clear and disinterested philosophical understanding of ecology which can help identify the practical lessons of science. Conversely, the urgent practical demands humanity faces today cannot help but direct scientific and philosophical investigation toward the basis of those ecological challenges that threaten human survival. This book will help to fuel the timely renaissance of interest in philosophy of ecology that is now oc...

  2. Field theory and strings

    International Nuclear Information System (INIS)

    Bonara, L.; Cotta-Ramusino, P.; Rinaldi, M.

    1987-01-01

    It is well-known that type I and heterotic superstring theories have a zero mass spectrum which correspond to the field content of N=1 supergravity theory coupled to supersymmetric Yang-Mills theory in 10-D. The authors study the field theory ''per se'', in the hope that simple consistency requirements will determine the theory completely once one knows the field content inherited from string theory. The simplest consistency requirements are: N=1 supersymmetry; and absence of chiral anomalies. This is what the authors discuss in this paper here leaving undetermined the question of the range of validity of the resulting field theory. As is known, a model of N=1 supergravity (SUGRA) coupled to supersymmetric Yang-Mills (SYM) theory was known in the form given by Chapline and Manton. The coupling of SUGRA to SYM was determined by the definition of the ''field strength'' 3-form H in this paper

  3. D. McKenzie, C. Miller and D.A. Falk, eds. The Landscape Ecology of Fire [book review

    Science.gov (United States)

    Eric J. Gustafson

    2012-01-01

    In the Foreword of this volume is the statement that "landscape ecology is the 'glue' that holds ecosystem theory together and nowhere is that more evident than in the study of wildland fire ecology." The Landscape Ecology of Fire summarizes how landscape ecology has contributed to, and been formed by, the study...

  4. Development of the simple evaluation method of the soil biomass by the ATP measurement

    Czech Academy of Sciences Publication Activity Database

    Urashima, Y.; Nakajima, M.; Kaneda, Satoshi; Murakami, T.

    2007-01-01

    Roč. 78, č. 2 (2007), s. 187-190 ISSN 0029-0610 Institutional research plan: CEZ:AV0Z60660521 Keywords : simple evaluation method * soil biomass * ATP measurement Subject RIV: EH - Ecology, Behaviour

  5. What Is a Simple Liquid?

    Directory of Open Access Journals (Sweden)

    Trond S. Ingebrigtsen

    2012-03-01

    characterized in three quite different ways: (1 chemically by the fact that the liquid’s properties are fully determined by interactions from the molecules within the FCS, (2 physically by the fact that there are isomorphs in the phase diagram, i.e., curves along which several properties like excess entropy, structure, and dynamics, are invariant in reduced units, and (3 mathematically by the fact that throughout the phase diagram the reduced-coordinate constant-potential-energy hypersurfaces define a one-parameter family of compact Riemannian manifolds. No proof is given that the chemical characterization follows from the strong correlation property, but we show that this FCS characterization is consistent with the existence of isomorphs in strongly correlating liquids’ phase diagram. Finally, we note that the FCS characterization of simple liquids calls into question the physical basis of standard perturbation theory, according to which the repulsive and attractive forces play fundamentally different roles for the physics of liquids.

  6. Using ecological production functions to link ecological ...

    Science.gov (United States)

    Ecological production functions (EPFs) link ecosystems, stressors, and management actions to ecosystem services (ES) production. Although EPFs are acknowledged as being essential to improve environmental management, their use in ecological risk assessment has received relatively little attention. Ecological production functions may be defined as usable expressions (i.e., models) of the processes by which ecosystems produce ES, often including external influences on those processes. We identify key attributes of EPFs and discuss both actual and idealized examples of their use to inform decision making. Whenever possible, EPFs should estimate final, rather than intermediate, ES. Although various types of EPFs have been developed, we suggest that EPFs are more useful for decision making if they quantify ES outcomes, respond to ecosystem condition, respond to stressor levels or management scenarios, reflect ecological complexity, rely on data with broad coverage, have performed well previously, are practical to use, and are open and transparent. In an example using pesticides, we illustrate how EPFs with these attributes could enable the inclusion of ES in ecological risk assessment. The biggest challenges to ES inclusion are limited data sets that are easily adapted for use in modeling EPFs and generally poor understanding of linkages among ecological components and the processes that ultimately deliver the ES. We conclude by advocating for the incorporation into E

  7. The ecological mandala of M. K. Gandhi

    Science.gov (United States)

    Willey, Priscilla Kamala

    Industrialization and urbanization have brought about environmental disassociation. The works of Orr, Naess, College of the Atlantic, conservation groups, communities such as Findhorn indicate that responsible personal behavior to the earth is an evident necessity, and growing requirement. This study is a philosophical analysis of Mohandas Karamchand Gandhi's ecological education. Gandhi's role in the political emancipation India was inseparable from the groundwork he laid environmentally, to light a path in creating a new India through a new human consciousness. Gandhi sought to transform his own life and mind radically along with many dimensions of the social, physical and ideational environment around him with his experiments with Truth. This study accepts as ecological Reality, the Truth that Gandhi claimed to be the purpose and source of his life. The study builds a literary Ecological Mandala, through the theoretical background of Gandhi's ecological education. Using inherently universal human ethics, which I have called universal Simples consisting of three groups, the framework of the Ecological Mandala is built (chapters 2 and 3). The Simples assist the observances, which I have also called the root tools, as they act upon the core of the individual. These are; fearlessness, control of the palate, tolerance, equality, non-possession and non-stealing which found its ideal in Trusteeship, bread labor and brahmacharya. The goal of these observances was Ahimsa, or Truth. Satyagraha is explained as a comprehensive methodology for ecological education which utilizes all aspects of the universal Simples. The fast is a weapon in its arsenal. The applications of Gandhi's ecological education are examined as seen in the eco-communities he established in South Africa, Phoenix and Tolstoy, and in the Ashrams in India (chapters 4 and 5). The eco-communities served as prototypes for the national education that Gandhi sought to implement through the constructive program

  8. Ecological Factors in Human Development.

    Science.gov (United States)

    Cross, William E

    2017-05-01

    Urie Bronfenbrenner (1992) helped developmental psychologists comprehend and define "context" as a rich, thick multidimensional construct. His ecological systems theory consists of five layers, and within each layer are developmental processes unique to each layer. The four articles in this section limit the exploration of context to the three innermost systems: the individual plus micro- and macrolayers. Rather than examine both the physical features and processes, the articles tend to focus solely on processes associated with a niche. Processes explored include social identity development, social network dynamics, peer influences, and school-based friendship patterns. The works tend to extend the generalization of extant theory to the developmental experience of various minority group experiences. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

  9. Adopting an ecological view of metropolitan landscape: the case of "three circles" system for ecological construction and restoration in Beijing area.

    Science.gov (United States)

    Zhang, Feng; Zhang, Xin-shi

    2004-01-01

    Ecological construction and restoration for sustainable development are now a driving paradigm. It is increasingly recognized that ecological principles, especially landscape ecology theory, are not only necessary but also essential to maintain the long-term sustainability worldwide. Key landscape ecology principles-element, structure and process, dynamics, heterogeneity, hierarchies, connectivity, place and time were reviewed, and use Beijing area as a case study to illustrate how these principles might be applied to ecological construction and restoration, to eventually achieve sustainability. An example to more effectively incorporate the ecological principles in sustainable planning in China was presented.

  10. Dimensional analysis made simple

    International Nuclear Information System (INIS)

    Lira, Ignacio

    2013-01-01

    An inductive strategy is proposed for teaching dimensional analysis to second- or third-year students of physics, chemistry, or engineering. In this strategy, Buckingham's theorem is seen as a consequence and not as the starting point. In order to concentrate on the basics, the mathematics is kept as elementary as possible. Simple examples are suggested for classroom demonstrations of the power of the technique and others are put forward for homework or experimentation, but instructors are encouraged to produce examples of their own. (paper)

  11. Applied mathematics made simple

    CERN Document Server

    Murphy, Patrick

    1982-01-01

    Applied Mathematics: Made Simple provides an elementary study of the three main branches of classical applied mathematics: statics, hydrostatics, and dynamics. The book begins with discussion of the concepts of mechanics, parallel forces and rigid bodies, kinematics, motion with uniform acceleration in a straight line, and Newton's law of motion. Separate chapters cover vector algebra and coplanar motion, relative motion, projectiles, friction, and rigid bodies in equilibrium under the action of coplanar forces. The final chapters deal with machines and hydrostatics. The standard and conte

  12. Data processing made simple

    CERN Document Server

    Wooldridge, Susan

    2013-01-01

    Data Processing: Made Simple, Second Edition presents discussions of a number of trends and developments in the world of commercial data processing. The book covers the rapid growth of micro- and mini-computers for both home and office use; word processing and the 'automated office'; the advent of distributed data processing; and the continued growth of database-oriented systems. The text also discusses modern digital computers; fundamental computer concepts; information and data processing requirements of commercial organizations; and the historical perspective of the computer industry. The

  13. ASP made simple

    CERN Document Server

    Deane, Sharon

    2003-01-01

    ASP Made Simple provides a brief introduction to ASP for the person who favours self teaching and/or does not have expensive computing facilities to learn on. The book will demonstrate how the principles of ASP can be learned with an ordinary PC running Personal Web Server, MS Access and a general text editor like Notepad.After working through the material readers should be able to:* Write ASP scripts that can display changing information on a web browser* Request records from a remote database or add records to it* Check user names & passwords and take this knowledge forward, either for their

  14. Gauge theory and elementary particles

    International Nuclear Information System (INIS)

    Zwirn, H.

    1982-01-01

    The present orientation of particle physics, founded on local gauge invariance theories and spontaneous symmetry breaking is described in a simple formalism. The application of these ideas to the latest theories describing electromagnetic and weak interactions (Glashow, Weinberg, Salam models) and strong interactions, quantum chromodynamics, is presented so as to give a general picture of the mechanisms subtending these theories [fr

  15. Probabilistic simple sticker systems

    Science.gov (United States)

    Selvarajoo, Mathuri; Heng, Fong Wan; Sarmin, Nor Haniza; Turaev, Sherzod

    2017-04-01

    A model for DNA computing using the recombination behavior of DNA molecules, known as a sticker system, was introduced by by L. Kari, G. Paun, G. Rozenberg, A. Salomaa, and S. Yu in the paper entitled DNA computing, sticker systems and universality from the journal of Acta Informatica vol. 35, pp. 401-420 in the year 1998. A sticker system uses the Watson-Crick complementary feature of DNA molecules: starting from the incomplete double stranded sequences, and iteratively using sticking operations until a complete double stranded sequence is obtained. It is known that sticker systems with finite sets of axioms and sticker rules generate only regular languages. Hence, different types of restrictions have been considered to increase the computational power of sticker systems. Recently, a variant of restricted sticker systems, called probabilistic sticker systems, has been introduced [4]. In this variant, the probabilities are initially associated with the axioms, and the probability of a generated string is computed by multiplying the probabilities of all occurrences of the initial strings in the computation of the string. Strings for the language are selected according to some probabilistic requirements. In this paper, we study fundamental properties of probabilistic simple sticker systems. We prove that the probabilistic enhancement increases the computational power of simple sticker systems.

  16. Simple stochastic simulation.

    Science.gov (United States)

    Schilstra, Maria J; Martin, Stephen R

    2009-01-01

    Stochastic simulations may be used to describe changes with time of a reaction system in a way that explicitly accounts for the fact that molecules show a significant degree of randomness in their dynamic behavior. The stochastic approach is almost invariably used when small numbers of molecules or molecular assemblies are involved because this randomness leads to significant deviations from the predictions of the conventional deterministic (or continuous) approach to the simulation of biochemical kinetics. Advances in computational methods over the three decades that have elapsed since the publication of Daniel Gillespie's seminal paper in 1977 (J. Phys. Chem. 81, 2340-2361) have allowed researchers to produce highly sophisticated models of complex biological systems. However, these models are frequently highly specific for the particular application and their description often involves mathematical treatments inaccessible to the nonspecialist. For anyone completely new to the field to apply such techniques in their own work might seem at first sight to be a rather intimidating prospect. However, the fundamental principles underlying the approach are in essence rather simple, and the aim of this article is to provide an entry point to the field for a newcomer. It focuses mainly on these general principles, both kinetic and computational, which tend to be not particularly well covered in specialist literature, and shows that interesting information may even be obtained using very simple operations in a conventional spreadsheet.

  17. [Landscape ecological security pattern during urban expansion of Nanchong City].

    Science.gov (United States)

    Li, Sui; Shi, Tie-mao; Fu, Shi-lei; Zhou, Le; Liu, Miao; Wang, Wei

    2011-03-01

    Based on the theory of landscape ecological security pattern and the RS and GIS techniques, this paper analyzed the distribution of ecological security grades in Nanchong City, taking six elements including terrain condition, flood hazard, soil erosion, vegetation cover, geological disaster, and biological protection as the ecological constraints (or determinants) of urban expansion. According to the minimum cumulative resistance model, the ecological corridors and ecological nodes were built to strengthen the space contact of ecological network, and, on the basis of the protection of ecological safety, the reasonable trend of urban expansion and the optimization of space layout were investigated. The results showed that the ecological security of Nanchong City was quite good, with the regions of low ecological security mainly distributed in the west suburban mountains and the downstream region of Jialing River in the south of the City. Ecological elements were the most important constraints for the future expansion of urban space. There were more spaces for the urban expansion in the southern and northern parts of Nanchong City. To develop satellite towns would be the best selection to guarantee the ecological security of the city.

  18. Development of Ecological Buildings

    Directory of Open Access Journals (Sweden)

    Andrius Keizikas

    2011-04-01

    Full Text Available The article presents research on ecological buildings and their influence on the constructional sphere. The aim of the paper is to reveal the essence of ecological architecture showing substantial progress and its potential to stimulate architectural and technological growth. The article also describes relations between the ideas of ecological buildings and the ‘passive house’ concepts and aspects of development as well as describes the possibilities of improving building sustainability and energy efficiency. Article in Lithuanian

  19. The ecological economics: An ecological economics

    International Nuclear Information System (INIS)

    Castiblanco R, Carmenza

    2007-01-01

    Ecological Economics arise as a scientific discipline aimed to integrate concepts of economics, ecology, thermodynamics, ethic and other natural and social sciences in order to incorporate a biophysical and integrated perspective of the inter dependences between economies and environment, from a plural conception and a methodology beyond disciplines. Ecological Economics studies the black box of economic processes usually excluded of the traditional economics: thermodynamics and ecology. Although it is relatively a new field of study, it has been strengthening its theoretical framework with scientific basis and analytic principles that lead to its identification as a new discipline that show a whole new paradigm. The scope of this article is to show the conceptual and methodological bases, the main founders, approaches and central debates of this new discipline. This brief introduction is a preamble to the papers of the meeting Ecological Economics: a perspective for Colombia included in this number, that took place on September 22 - 27 of 2007, at the National University of Colombia at Bogota. During tree days national and international experts, professors, researchers, workers of environmental sector and people interested on environmental issues joined together to know the conceptual and methodological achievements reached of this discipline; as well as to analyse and evaluate the environmental problems of the country, from the systemic, interdisciplinary and general perspective that it promotes

  20. The Methodology of Psychological Research of Ecological Consciousness

    Directory of Open Access Journals (Sweden)

    Irina A. Shmeleva

    2009-01-01

    Full Text Available The paper examines the methodological principles of the psychological study of ecological consciousness as one of the urgent interdisciplinary problems of XX–XXI century, caused by the aggravation of global ecological problems and the need for the realization of the “sustainable development”ideas. Ecological consciousness is considered as multilayered, dynamic, reflexive element of human consciousness, incorporating multivariate, holistic aspects of interaction of the human being as the H.S. and the Humanity representative with the environment and the Planet. The possibility of the more active introduction of Russian psychology in the process is argued for in connection with the existing conceptual approaches, which compose the methodological basis for ecological consciousness research. Among these approaches are considered: the principles of holistic study of the human being by B. Ananyev, the methodology of system psychological description by V. Gansen and G. Sukhodolsky, the idea of reflexivity of consciousness by S. Rubinstein, the humanitarian- ecological imperative of the development of consciousness by V. Zinchenko, the theory of relations by V. Myasishev, consideration of ecological consciousness as relation to nature by S. Deryabo and V. Yasvin, theories of consciousness by V. Petrenko, V. Allakhverdov and other Russian psychologists. The value component of ecological consciousness is distinguished as the most significant. The possibility of applying the Values’ theory of the by S. Schwartz for studying the ecological values is discussed along with the prognostic potential of the universalism value.

  1. The Power of M Theory

    OpenAIRE

    Schwarz, John H.

    1995-01-01

    A proposed duality between type IIB superstring theory on R^9 X S^1 and a conjectured 11D fundamental theory (``M theory'') on R^9 X T^2 is investigated. Simple heuristic reasoning leads to a consistent picture relating the various p-branes and their tensions in each theory. Identifying the M theory on R^{10} X S^1 with type IIA superstring theory on R^{10}, in a similar fashion, leads to various relations among the p-branes of the IIA theory.

  2. Emerging Beliefs Frustrate Ecological Literacy and Meaning-Making for Students

    Science.gov (United States)

    Fleischer, Stuart

    2011-01-01

    In their treatise, Mitchell and Mueller extend David Orr's notions of ecological literacy (2005) to include biophilia (Wilson "1984") and ecojustice (Mueller "2009"). In his writings, David Orr claims that the US is in an "ecological crisis" and that this stems from a crisis of education. The authors outline Orr's theory of ecological literacy as…

  3. Long-term ecological research in a human-dominated world

    Science.gov (United States)

    G. Philip Robertson; Scott L. Collins; David R. Foster; Nicholas Brokaw; Hugh W. Ducklow; Ted L. Gragson; Corinna Gries; Stephen K. Hamilton; A. David McGuire; John C. Moore; Emily H. Stanley; Robert B. Waide; Mark W. Williams

    2012-01-01

    The US Long Term Ecological Research (LTER) Network enters its fourth decade with a distinguished record of achievement in ecological science. The value of long-term observations and experiments has never been more important for testing ecological theory and for addressing today’s most difficult environmental challenges. The network’s potential for tackling emergent...

  4. Beyond urban legends: an emerging framework of urban ecology, as illustrated by the Baltimore Ecosystem Study

    Science.gov (United States)

    Steward T.A. Pickett; Mary L. Cadenasso; J. Morgan Grove; Peter M. Groffman; Lawrence E. Band; Christopher G. Boone; William R., Jr. Burch; Susan B. Grimmond; John Hom; Jennifer C. Jenkins; Neely L. Law; Charles H. Nilon; Richard V. Pouyat; Katalin Szlavecz; Paige S. Warren; Matthew A. Wilson

    2008-01-01

    The emerging discipline of urban ecology is shifting focus from ecological processes embedded within cities to integrative studies of large urban areas as biophysical-social complexes. Yet this discipline lacks a theory. Results from the Baltimore Ecosystem Study, part of the Long Term Ecological Research Network, expose new assumptions and test existing assumptions...

  5. Ecological risk assessment

    National Research Council Canada - National Science Library

    Suter, Glenn W; Barnthouse, L. W. (Lawrence W)

    2007-01-01

    Ecological risk assessment is commonly applied to the regulation of chemicals, the remediation of contaminated sites, the monitoring of importation of exotic organisms, the management of watersheds...

  6. Chemical ecology of fungi.

    Science.gov (United States)

    Spiteller, Peter

    2015-07-01

    Fungi are widespread in nature and have conquered nearly every ecological niche. Fungi occur not only in terrestrial but also in freshwater and marine environments. Moreover, fungi are known as a rich source of secondary metabolites. Despite these facts, the ecological role of many of these metabolites is still unknown and the chemical ecology of fungi has not been investigated systematically so far. This review intends to present examples of the various chemical interactions of fungi with other fungi, plants, bacteria and animals and to give an overview of the current knowledge of fungal chemical ecology.

  7. Quantum field theory

    CERN Document Server

    Mandl, Franz

    2010-01-01

    Following on from the successful first (1984) and revised (1993) editions, this extended and revised text is designed as a short and simple introduction to quantum field theory for final year physics students and for postgraduate students beginning research in theoretical and experimental particle physics. The three main objectives of the book are to: Explain the basic physics and formalism of quantum field theory To make the reader proficient in theory calculations using Feynman diagrams To introduce the reader to gauge theories, which play a central role in elementary particle physic

  8. Elements of set theory

    CERN Document Server

    Enderton, Herbert B

    1977-01-01

    This is an introductory undergraduate textbook in set theory. In mathematics these days, essentially everything is a set. Some knowledge of set theory is necessary part of the background everyone needs for further study of mathematics. It is also possible to study set theory for its own interest--it is a subject with intruiging results anout simple objects. This book starts with material that nobody can do without. There is no end to what can be learned of set theory, but here is a beginning.

  9. Beyond Simple Configurations

    DEFF Research Database (Denmark)

    Decreton, Benoit; Dellestrand, Henrik; Kappen, Philip

    2017-01-01

    We investigate “dual headquarters involvement”, i.e., corporate and divisional headquarters’ simultaneous involvement in innovation development projects hosted by subsidiaries of multibusiness firms. Drawing on selective hierarchical involvement theory and the literature on subsidiary network...... embeddedness, we analyze 83 innovation projects in 22 multibusiness firms and find that the number of partners in the projects, rather than subsidiary intra- and inter-divisional embeddedness acts as a driver of dual headquarters involvement. We do however find that intra- and inter-divisional embeddedness...... conceptualizations of headquarters and that considering different dimensions of the innovating subsidiary’s network helps in explaining dual headquarters involvement....

  10. Simple implementation of general dark energy models

    International Nuclear Information System (INIS)

    Bloomfield, Jolyon K.; Pearson, Jonathan A.

    2014-01-01

    We present a formalism for the numerical implementation of general theories of dark energy, combining the computational simplicity of the equation of state for perturbations approach with the generality of the effective field theory approach. An effective fluid description is employed, based on a general action describing single-scalar field models. The formalism is developed from first principles, and constructed keeping the goal of a simple implementation into CAMB in mind. Benefits of this approach include its straightforward implementation, the generality of the underlying theory, the fact that the evolved variables are physical quantities, and that model-independent phenomenological descriptions may be straightforwardly investigated. We hope this formulation will provide a powerful tool for the comparison of theoretical models of dark energy with observational data

  11. On Touristic Ecological Footprint of Macau

    Institute of Scientific and Technical Information of China (English)

    Zhang Meng; Yang Yu

    2012-01-01

    Despite its tiny territory, Macau boasts a large volume of tourist activities, which serves as the pillar of its economy. En- vironment and natural resources are the cornerstone of tourism, but are also subject to the negative impact of tourism. Based on the theory and methodology of ecological footprint analysis, this paper calculated the touristic ecological footprint and deficit of Macau in 2009, in an effort to bring to light the current status of excessive consumption of resources by tourism. As the findings show, the non-h'ansferable touristic ecological footprint and touristic ecologi- cal deficit of Macau in 2009 are respectively 18 300.891 gha and 12 737.584 gha, and the former is 3.29 times as large as the tour- istic ecological carrying capacity. Touristic ecological footprint of Macau is highly efficient in economic sense but currently tourism is developing in an unsustainable manner, so appropriate initiatives are in need to strike a balance between tourism development and resource conservation and to promote the sustainability of tourism industry of Macau.

  12. Nature and history today: the ecological crisis

    Directory of Open Access Journals (Sweden)

    Luciano ESPINOSA RUBIO

    2012-02-01

    Full Text Available Today, the Nature-History relations are the ecological ones: we are living in a global eco-bio-techno-noos-sphere and that means that ecological crisis is a crisis of civilization too. Above all, the climate change and its social and political consequences will have a great impact in our lives, and we must respond without losing our rights. In the intellectual way, we need new narrations in order to affront the situation and perhaps the theory of the lesser evil is one of the better answers that we can find.

  13. Beyond Simple Headquarters Configurations

    DEFF Research Database (Denmark)

    Dellestrand, Henrik; Kappen, Philip; Nell, Phillip Christopher

    We investigate “dual headquarters involvement”, i.e. corporate and divisional headquarters’ simultaneous involvement in subsidiaries’ innovation development projects. Analyses draw on 85 innovation projects in 23 multibusiness firms and reveal that cross-divisional innovation importance, i.......e., an innovation that is important for the firm beyond the divisional boundaries, drives dual headquarters involvement in innovation development. Contrary to expectations, on average, a non-significant effect of cross-divisional embeddedness on dual headquarters involvement is found. Yet, both cross......-divisional importance and embeddedness effects are contingent on the overall complexity of the innovation project as signified by the size of the development network. The results lend support for the notion that parenting in complex structures entails complex headquarters structures and that we need to go beyond simple...

  14. Simple relation algebras

    CERN Document Server

    Givant, Steven

    2017-01-01

    This monograph details several different methods for constructing simple relation algebras, many of which are new with this book. By drawing these seemingly different methods together, all are shown to be aspects of one general approach, for which several applications are given. These tools for constructing and analyzing relation algebras are of particular interest to mathematicians working in logic, algebraic logic, or universal algebra, but will also appeal to philosophers and theoretical computer scientists working in fields that use mathematics. The book is written with a broad audience in mind and features a careful, pedagogical approach; an appendix contains the requisite background material in relation algebras. Over 400 exercises provide ample opportunities to engage with the material, making this a monograph equally appropriate for use in a special topics course or for independent study. Readers interested in pursuing an extended background study of relation algebras will find a comprehensive treatme...

  15. A Simple Harmonic Universe

    Energy Technology Data Exchange (ETDEWEB)

    Graham, Peter W.; /Stanford U., ITP; Horn, Bart; Kachru, Shamit; /Stanford U., ITP /SLAC; Rajendran, Surjeet; /Johns Hopkins U. /Stanford U., ITP; Torroba, Gonzalo; /Stanford U., ITP /SLAC

    2011-12-14

    We explore simple but novel bouncing solutions of general relativity that avoid singularities. These solutions require curvature k = +1, and are supported by a negative cosmological term and matter with -1 < w < -1 = 3. In the case of moderate bounces (where the ratio of the maximal scale factor a{sub +} to the minimal scale factor a{sub -} is {Omicron}(1)), the solutions are shown to be classically stable and cycle through an infinite set of bounces. For more extreme cases with large a{sub +} = a{sub -}, the solutions can still oscillate many times before classical instabilities take them out of the regime of validity of our approximations. In this regime, quantum particle production also leads eventually to a departure from the realm of validity of semiclassical general relativity, likely yielding a singular crunch. We briefly discuss possible applications of these models to realistic cosmology.

  16. SIMPLE for industrial radiography

    International Nuclear Information System (INIS)

    Azhar Azmi; Abd Nassir Ibrahim; Siti Madiha Muhammad Amir; Glam Hadzir Patai Mohamad; Saidi Rajab

    2004-01-01

    The first thing industrial radiographers have to do before commencing radiography works is to determine manually the amount of correct exposure that the film need to be exposed in order to obtain the right density. The amount of exposure depends on many variables such as type of radioisotope, type of film, nature of test-object and its orientation, and specific arrangement related to object location and configuration. In many cases radiography works are rejected because of radiographs fail to meet certain reference criteria as defined in the applicable standard. One of the main reasons of radiograph rejection is due to inadequate exposure received by the films. SIMPLE is a software specially developed to facilitate the calculation of gamma-radiography exposure. By using this software and knowing radiographic parameters to be encountered during the work, it is expected that human error will be minimized, thus enhancing the quality and productivity of NDT jobs. (Author)

  17. Molecular genetics made simple

    Directory of Open Access Journals (Sweden)

    Heba Sh. Kassem

    2012-07-01

    Full Text Available Genetics have undoubtedly become an integral part of biomedical science and clinical practice, with important implications in deciphering disease pathogenesis and progression, identifying diagnostic and prognostic markers, as well as designing better targeted treatments. The exponential growth of our understanding of different genetic concepts is paralleled by a growing list of genetic terminology that can easily intimidate the unfamiliar reader. Rendering genetics incomprehensible to the clinician however, defeats the very essence of genetic research: its utilization for combating disease and improving quality of life. Herein we attempt to correct this notion by presenting the basic genetic concepts along with their usefulness in the cardiology clinic. Bringing genetics closer to the clinician will enable its harmonious incorporation into clinical care, thus not only restoring our perception of its simple and elegant nature, but importantly ensuring the maximal benefit for our patients.

  18. Molecular genetics made simple

    Science.gov (United States)

    Kassem, Heba Sh.; Girolami, Francesca; Sanoudou, Despina

    2012-01-01

    Abstract Genetics have undoubtedly become an integral part of biomedical science and clinical practice, with important implications in deciphering disease pathogenesis and progression, identifying diagnostic and prognostic markers, as well as designing better targeted treatments. The exponential growth of our understanding of different genetic concepts is paralleled by a growing list of genetic terminology that can easily intimidate the unfamiliar reader. Rendering genetics incomprehensible to the clinician however, defeats the very essence of genetic research: its utilization for combating disease and improving quality of life. Herein we attempt to correct this notion by presenting the basic genetic concepts along with their usefulness in the cardiology clinic. Bringing genetics closer to the clinician will enable its harmonious incorporation into clinical care, thus not only restoring our perception of its simple and elegant nature, but importantly ensuring the maximal benefit for our patients. PMID:25610837

  19. SIMPLE LIFE AND RELIGION

    Directory of Open Access Journals (Sweden)

    Ahmet YILDIRIM

    2014-07-01

    Full Text Available Individuals in terms of the economy in which we live is one of the most important phenomenon of the century. This phenomenon present itself as the only determinant of people's lives by entering almost makes itself felt. The mo st obvious objective needs of the economy by triggering motive is to induce people to consume . Consumer culture pervades all aspects of the situation are people . Therefore, these people have the blessing of culture , beauty and value all in the name of w hatever is consumed. This is way out of the siege of moral and religious values we have is to go back again . Referred by local cultural and religious values, based on today increasingly come to the fore and the Muslim way of life appears to be close to th e plain / lean preferred by many people life has been a way of life. Even the simple life , a way of life in the Western world , a conception of life , a philosophy, a movement as it has become widely accepted. Here in determining the Muslim way of life Pr ophet. Prophet (sa lived the kind of life a very important model, sample, and determining which direction is known. Religious values, which is the carrier of the prophets, sent to the society they have always been examples and models. Because every aspect of human life, his life style and the surrounding area has a feature. We also value his life that he has unknowingly and without learning and skills and to understand it is not possible to live our religion . We also our presentation, we mainly of Islam o utlook on life and predicted life - style, including the Prophet of Islam 's (sa simple life to scrutinize and lifestyle issues related to reveal , in short Islam's how life has embraced and the Prophet. Prophet's will try to find answers to questions reg arding how to live.

  20. Revisiting the evolution of ecological specialization, with emphasis on insect-plant interactions.

    Science.gov (United States)

    Forister, M L; Dyer, L A; Singer, M S; Stireman, J O; Lill, J T

    2012-05-01

    Ecological specialization is a fundamental and well-studied concept, yet its great reach and complexity limit current understanding in important ways. More than 20 years after the publication of D. J. Futuyma and G. Moreno's oft-cited, major review of the topic, we synthesize new developments in the evolution of ecological specialization. Using insect-plant interactions as a model, we focus on important developments in four critical areas: genetic architecture, behavior, interaction complexity, and macroevolution. We find that theory based on simple genetic trade-offs in host use is being replaced by more subtle and complex pictures of genetic architecture, and multitrophic interactions have risen as a necessary framework for understanding specialization. A wealth of phylogenetic data has made possible a more detailed consideration of the macroevolutionary dimension of specialization, revealing (among other things) bidirectionality in transitions between generalist and specialist lineages. Technological advances, including genomic sequencing and analytical techniques at the community level, raise the possibility that the next decade will see research on specialization spanning multiple levels of biological organization in non-model organisms, from genes to populations to networks of interactions in natural communities. Finally, we offer a set of research questions that we find to be particularly pressing and fruitful for future research on ecological specialization.

  1. Measuring sustainability. Why the ecological footprint is bad economics and bad environmental science

    Energy Technology Data Exchange (ETDEWEB)

    Fiala, Nathan [Department of Economics, University of California, Irvine, 3151 Social Science Plaza, Irvine, CA 92697-5100 (United States)

    2008-11-01

    The ecological footprint is a measure of the resources necessary to produce the goods that an individual or population consumes. It is also used as a measure of sustainability, though evidence suggests that it falls short. The assumptions behind footprint calculations have been extensively criticized; I present here further evidence that it fails to satisfy simple economic principles because the basic assumptions are contradicted by both theory and historical data. Specifically, I argue that the footprint arbitrarily assumes both zero greenhouse gas emissions, which may not be ex ante optimal, and national boundaries, which makes extrapolating from the average ecological footprint problematic. The footprint also cannot take into account intensive production, and so comparisons to biocapacity are erroneous. Using only the assumptions of the footprint then, one could argue that the Earth can sustain greatly increased production, though there are important limitations that the footprint cannot address, such as land degradation. Finally, the lack of correlation between land degradation and the ecological footprint obscures the effects of a larger sustainability problem. Better measures of sustainability would address these issues directly. (author)

  2. Stochastic dynamical models for ecological regime shifts

    DEFF Research Database (Denmark)

    Møller, Jan Kloppenborg; Carstensen, Jacob; Madsen, Henrik

    the physical and biological knowledge of the system, and nonlinearities introduced here can generate regime shifts or enhance the probability of regime shifts in the case of stochastic models, typically characterized by a threshold value for the known driver. A simple model for light competition between...... definition and stability of regimes become less subtle. Ecological regime shifts and their modeling must be viewed in a probabilistic manner, particularly if such model results are to be used in ecosystem management....

  3. The several faces of fear: ecological consequences of predation risk in a lagoon model system

    Directory of Open Access Journals (Sweden)

    Rafael Dettogni Guariento

    Full Text Available AIM: The aim of this study was to evaluate the role of predation risk on the occurrence of trophic cascades in a benthic food chain, and detect if the ecological consequences of predation risk can reverberate in patterns observed across different hierarchical scales, such as prey size, prey growth efficiency and nutrient recycling patterns. METHODS: The model system used in the present experiment consisted of a simple linear food chain comprising a predator, a consumer and periphyton as basal resources. For 2 weeks, we manipulated predation risk using caged predators, incapable of killing their prey, across twelve outdoor mesocosms, simulating natural lagoon conditions. RESULTS: Our results showed that predation risk can be responsible for the occurrence of a trophic cascade and the strength of the cascade is proportional to the intensity of risk. Predation risk can also negatively influence prey biomass and growth efficiency as well as affect nutrient recycling patterns by altering prey nutrient excretion rates. Through a simple mathematical formulation, we attempted to show that individual-level experimental results can be generalized to natural populations if evolutionary constraints to prey fitness can be reproduced in experimental conditions. CONCLUSIONS: Our results corroborate to integrate ecosystem dynamics with animal behavior, highlighting that not only bottom-up but also top-down mechanisms are responsible for determining ecosystem properties. We ultimately claim that prey adaptive foraging may serve to integrate ecosystem and evolutionary ecology, resulting in the development of a more robust and predictive theory of the functioning of aquatic ecosystems.

  4. Ecological analyses and applications

    International Nuclear Information System (INIS)

    Brocksen, R.W.

    1977-01-01

    Progress is reported on the following: analysis of ecological impacts of construction and operation of nuclear power plants; fossil energy environmental project; ecological analysis of geothermal energy development; HUD modular integrated utility systems; expansion of uranium enrichment facilities at Portsmouth; environmental standard review plans; environmental assessment of cooling reservoirs; and analysis of fish impingement at power plants in the southeastern United States

  5. Ecology and economy

    International Nuclear Information System (INIS)

    Menard, M.; Bischoff, J.

    1980-01-01

    The green movement challenges workers' unions and socialists. Who are the 'Greens', and what do they want. Where do their theoretical fundamentals come from. Will an ecological economy be able to function. Are the 'Greens' leftists or dreamers fighting against progress. Arguments for trade unionists and socialists in the ecological controversy. (orig.) [de

  6. Ecological analyses and applications

    International Nuclear Information System (INIS)

    Kroodsma, R.L.; Craig, R.B.; Hildebrand, S.G.

    1978-01-01

    Progress is reported on the following: assessment of nuclear power plants; ecological analysis of uranium mining, milling, and fuel fabrication; environmental impact statements concerning uranium enrichment facilities; site evaluations for storage of radioactive wastes; ecological analysis of geothermal energy development; enhanced oil recovery; environmental monitoring plan for modular integrated utility systems; and fossil energy environmental project

  7. Terrestrial Ecology Guide.

    Science.gov (United States)

    Morrison, James W., Ed.; Hall, James A., Ed.

    This collection of study units focuses on the study of the ecology of land habitats. Considered are such topics as map reading, field techniques, forest ecosystem, birds, insects, small mammals, soils, plant ecology, preparation of terrariums, air pollution, photography, and essentials of an environmental studies program. Each unit contains…

  8. Children's Ecology Books.

    Science.gov (United States)

    Lussenhop, Martha

    Selected for this listing of children's books are fiction and non-fiction books which add to an understanding of ecology, broadly considered here as the study of the interrelationships of organisms to each other and their environment. General ecology, natural resources, man and his environment, evolution and adaptation, appreciation, survival,…

  9. Gauge theory loop operators and Liouville theory

    International Nuclear Information System (INIS)

    Drukker, Nadav; Teschner, Joerg

    2009-10-01

    We propose a correspondence between loop operators in a family of four dimensional N=2 gauge theories on S 4 - including Wilson, 't Hooft and dyonic operators - and Liouville theory loop operators on a Riemann surface. This extends the beautiful relation between the partition function of these N=2 gauge theories and Liouville correlators found by Alday, Gaiotto and Tachikawa. We show that the computation of these Liouville correlators with the insertion of a Liouville loop operator reproduces Pestun's formula capturing the expectation value of a Wilson loop operator in the corresponding gauge theory. We prove that our definition of Liouville loop operators is invariant under modular transformations, which given our correspondence, implies the conjectured action of S-duality on the gauge theory loop operators. Our computations in Liouville theory make an explicit prediction for the exact expectation value of 't Hooft and dyonic loop operators in these N=2 gauge theories. The Liouville loop operators are also found to admit a simple geometric interpretation within quantum Teichmueller theory as the quantum operators representing the length of geodesics. We study the algebra of Liouville loop operators and show that it gives evidence for our proposal as well as providing definite predictions for the operator product expansion of loop operators in gauge theory. (orig.)

  10. Gauge theory loop operators and Liouville theory

    Energy Technology Data Exchange (ETDEWEB)

    Drukker, Nadav [Humboldt Univ. Berlin (Germany). Inst. fuer Physik; Gomis, Jaume; Okuda, Takuda [Perimeter Inst. for Theoretical Physics, Waterloo, ON (Canada); Teschner, Joerg [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2009-10-15

    We propose a correspondence between loop operators in a family of four dimensional N=2 gauge theories on S{sup 4} - including Wilson, 't Hooft and dyonic operators - and Liouville theory loop operators on a Riemann surface. This extends the beautiful relation between the partition function of these N=2 gauge theories and Liouville correlators found by Alday, Gaiotto and Tachikawa. We show that the computation of these Liouville correlators with the insertion of a Liouville loop operator reproduces Pestun's formula capturing the expectation value of a Wilson loop operator in the corresponding gauge theory. We prove that our definition of Liouville loop operators is invariant under modular transformations, which given our correspondence, implies the conjectured action of S-duality on the gauge theory loop operators. Our computations in Liouville theory make an explicit prediction for the exact expectation value of 't Hooft and dyonic loop operators in these N=2 gauge theories. The Liouville loop operators are also found to admit a simple geometric interpretation within quantum Teichmueller theory as the quantum operators representing the length of geodesics. We study the algebra of Liouville loop operators and show that it gives evidence for our proposal as well as providing definite predictions for the operator product expansion of loop operators in gauge theory. (orig.)

  11. Predictive systems ecology.

    Science.gov (United States)

    Evans, Matthew R; Bithell, Mike; Cornell, Stephen J; Dall, Sasha R X; Díaz, Sandra; Emmott, Stephen; Ernande, Bruno; Grimm, Volker; Hodgson, David J; Lewis, Simon L; Mace, Georgina M; Morecroft, Michael; Moustakas, Aristides; Murphy, Eugene; Newbold, Tim; Norris, K J; Petchey, Owen; Smith, Matthew; Travis, Justin M J; Benton, Tim G

    2013-11-22

    Human societies, and their well-being, depend to a significant extent on the state of the ecosystems that surround them. These ecosystems are changing rapidly usually in response to anthropogenic changes in the environment. To determine the likely impact of environmental change on ecosystems and the best ways to manage them, it would be desirable to be able to predict their future states. We present a proposal to develop the paradigm of predictive systems ecology, explicitly to understand and predict the properties and behaviour of ecological systems. We discuss the necessary and desirable features of predictive systems ecology models. There are places where predictive systems ecology is already being practised and we summarize a range of terrestrial and marine examples. Significant challenges remain but we suggest that ecology would benefit both as a scientific discipline and increase its impact in society if it were to embrace the need to become more predictive.

  12. Spatial ecology across scales.

    Science.gov (United States)

    Hastings, Alan; Petrovskii, Sergei; Morozov, Andrew

    2011-04-23

    The international conference 'Models in population dynamics and ecology 2010: animal movement, dispersal and spatial ecology' took place at the University of Leicester, UK, on 1-3 September 2010, focusing on mathematical approaches to spatial population dynamics and emphasizing cross-scale issues. Exciting new developments in scaling up from individual level movement to descriptions of this movement at the macroscopic level highlighted the importance of mechanistic approaches, with different descriptions at the microscopic level leading to different ecological outcomes. At higher levels of organization, different macroscopic descriptions of movement also led to different properties at the ecosystem and larger scales. New developments from Levy flight descriptions to the incorporation of new methods from physics and elsewhere are revitalizing research in spatial ecology, which will both increase understanding of fundamental ecological processes and lead to tools for better management.

  13. Ecological opportunity and the adaptive diversification of lineages.

    Science.gov (United States)

    Wellborn, Gary A; Langerhans, R Brian

    2015-01-01

    The tenet that ecological opportunity drives adaptive diversification has been central to theories of speciation since Darwin, yet no widely accepted definition or mechanistic framework for the concept currently exists. We propose a definition for ecological opportunity that provides an explicit mechanism for its action. In our formulation, ecological opportunity refers to environmental conditions that both permit the persistence of a lineage within a community, as well as generate divergent natural selection within that lineage. Thus, ecological opportunity arises from two fundamental elements: (1) niche availability, the ability of a population with a phenotype previously absent from a community to persist within that community and (2) niche discordance, the diversifying selection generated by the adaptive mismatch between a population's niche-related traits and the newly encountered ecological conditions. Evolutionary response to ecological opportunity is primarily governed by (1) spatiotemporal structure of ecological opportunity, which influences dynamics of selection and development of reproductive isolation and (2) diversification potential, the biological properties of a lineage that determine its capacity to diversify. Diversification under ecological opportunity proceeds as an increase in niche breadth, development of intraspecific ecotypes, speciation, and additional cycles of diversification that may themselves be triggered by speciation. Extensive ecological opportunity may exist in depauperate communities, but it is unclear whether ecological opportunity abates in species-rich communities. Because ecological opportunity should generally increase during times of rapid and multifarious environmental change, human activities may currently be generating elevated ecological opportunity - but so far little work has directly addressed this topic. Our framework highlights the need for greater synthesis of community ecology and evolutionary biology, unifying

  14. Stochastic processes and quantum theory

    International Nuclear Information System (INIS)

    Klauder, J.R.

    1975-01-01

    The author analyses a variety of stochastic processes, namely real time diffusion phenomena, which are analogues of imaginary time quantum theory and convariant imaginary time quantum field theory. He elaborates some standard properties involving probability measures and stochastic variables and considers a simple class of examples. Finally he develops the fact that certain stochastic theories actually exhibit divergences that simulate those of covariant quantum field theory and presents examples of both renormaizable and unrenormalizable behavior. (V.J.C.)

  15. The reticulating phylogeny of island biogeography theory.

    Science.gov (United States)

    Lomolino, Mark V; Brown, James H

    2009-12-01

    Biogeographers study all patterns in the geographic variation of life, from the spatial variation in genetic and physiological characteristics of cells and individuals, to the diversity and dynamics of biological communities among continental biotas or across oceanic archipelagoes. The field of island biogeography, in particular, has provided some genuinely transformative insights for the biological sciences, especially ecology and evolutionary biology. Our purpose here is to review the historical development of island biogeography theory during the 20th century by identifying the common threads that run through four sets of contributions made during this period, including those by Eugene Gordon Munroe (1948, 1953), Edward O. Wilson (1959, 1961), Frank W. Preston (1962a,b), and the seminal collaborations between Wilson and Robert H. MacArthur (1963, 1967), which revolutionized the field and served as its paradigm for nearly four decades. This epistemological account not only reviews the intriguing history of island theory, but it also includes fundamental lessons for advancing science through transformative integrations. Indeed, as is likely the case with many disciplines, island theory advanced not as a simple accumulation of facts and an orderly succession of theories and paradigms, but rather in fits and starts through a reticulating phylogeny of ideas and alternating periods of specialization and reintegration. We conclude this review with a summary of the salient features of this scientific revolution in the contest of Kuhn's structure, which strongly influenced theoretical advances during this period, and we then describe some of the fundamental assumptions and tenets of an emerging reintegration of island biogeography theory.

  16. What is dental ecology?

    Science.gov (United States)

    Cuozzo, Frank P; Sauther, Michelle L

    2012-06-01

    Teeth have long been used as indicators of primate ecology. Early work focused on the links between dental morphology, diet, and behavior, with more recent years emphasizing dental wear, microstructure, development, and biogeochemistry, to understand primate ecology. Our study of Lemur catta at the Beza Mahafaly Special Reserve, Madagascar, has revealed an unusual pattern of severe tooth wear and frequent tooth loss, primarily the result of consuming a fallback food for which these primates are not dentally adapted. Interpreting these data was only possible by combining our areas of expertise (dental anatomy [FC] and primate ecology [MS]). By integrating theoretical, methodological, and applied aspects of both areas of research, we adopted the term "dental ecology"-defined as the broad study of how teeth respond to the environment. Specifically, we view dental ecology as an interpretive framework using teeth as a vehicle for understanding an organism's ecology, which builds upon earlier work, but creates a new synthesis of anatomy and ecology that is only possible with detailed knowledge of living primates. This framework includes (1) identifying patterns of dental pathology and tooth use-wear, within the context of feeding ecology, behavior, habitat variation, and anthropogenic change, (2) assessing ways in which dental development and biogeochemical signals can reflect habitat, environmental change and/or stress, and (3) how dental microstructure and macro-morphology are adapted to, and reflect feeding ecology. Here we define dental ecology, provide a short summary of the development of this perspective, and place our new work into this context. Copyright © 2012 Wiley Periodicals, Inc.

  17. A simple scaler timer

    International Nuclear Information System (INIS)

    Narayanan, R.; Kalavathy, K.R.

    1989-01-01

    In any nuclear reactor, the start-up channels monitor the neutron flux during the start-up operation and give the alarm signals for safety purposes. Normally, a fission chamber is used as a detector to detect the low level neutron fluxes. The output of the detector after amplification and discrimination is shaped in a pulse shaper to provide constant width, constant height pulses for further processing in rate meters. The shaped pulses also go to a scaler timer, where they are counted for fixed time intervals and the accumulated counts displayed. The scaler timer described in this paper uses LSIs to get at a simple, compact and reliable unit. The design is centered around two LSIs. MOS Counter Timebase LSI type MK 5009P (U1) is used to generate the gating pulses. A 1 MHz crystal is used to generate the system clock. A 4 bit address selects the desired gating intervals of 1 or 10 or 100 seconds. In fact, MK 5009 is a very versatile LSI in a 16 pin DIP package, consisting of a MOS oscillator and divider chain. It is binary encoded for frequency division selection ranging from 1 to 36 x 10. With an input frequency of 1 MHz, MK 5009 provides the time periods of 1 μs to 100 seconds, one minute, ten minute and one hour periods. (author)

  18. A Simple Accelerometer Calibrator

    International Nuclear Information System (INIS)

    Salam, R A; Islamy, M R F; Khairurrijal; Munir, M M; Latief, H; Irsyam, M

    2016-01-01

    High possibility of earthquake could lead to the high number of victims caused by it. It also can cause other hazards such as tsunami, landslide, etc. In that case it requires a system that can examine the earthquake occurrence. Some possible system to detect earthquake is by creating a vibration sensor system using accelerometer. However, the output of the system is usually put in the form of acceleration data. Therefore, a calibrator system for accelerometer to sense the vibration is needed. In this study, a simple accelerometer calibrator has been developed using 12 V DC motor, optocoupler, Liquid Crystal Display (LCD) and AVR 328 microcontroller as controller system. The system uses the Pulse Wave Modulation (PWM) form microcontroller to control the motor rotational speed as response to vibration frequency. The frequency of vibration was read by optocoupler and then those data was used as feedback to the system. The results show that the systems could control the rotational speed and the vibration frequencies in accordance with the defined PWM. (paper)

  19. Philosophical Issues in Ecology: Recent Trends and Future Directions

    Directory of Open Access Journals (Sweden)

    Mark Colyvan

    2009-12-01

    Full Text Available Philosophy of ecology has been slow to become established as an area of philosophical interest, but it is now receiving considerable attention. This area holds great promise for the advancement of both ecology and the philosophy of science. Insights from the philosophy of science can advance ecology in a number of ways. For example, philosophy can assist with the development of improved models of ecological hypothesis testing and theory choice. Philosophy can also help ecologists understand the role and limitations of mathematical models in ecology. On the other side, philosophy of science will be advanced by having ecological case studies as part of the stock of examples. Ecological case studies can shed light on old philosophical topics as well as raise novel issues for the philosophy of science. For example, understanding theoretical terms such as "biodiversity" is important for scientific reasons, but such terms also carry political importance. Formulating appropriate definitions for such terms is thus not a purely scientific matter, and this may prompt a reevaluation of philosophical accounts of defining theoretical terms. We consider some of the topics currently receiving attention in the philosophy of ecology and other topics in need of attention. Our aim is to prompt further exchange between ecology and philosophy of science and to help set the agenda for future work in the philosophy of ecology. The topics covered include: the role of mathematical models, environmental problem formulation, biodiversity, and environmental ethics.

  20. Ecological quality of production: accounting approach on sustainable development

    Directory of Open Access Journals (Sweden)

    N.P. Syroid

    2016-12-01

    Full Text Available The specific weight of resource and power consuming technologies that is typical for Ukrainian economy, the absence of effective legal, administrative and economic mechanisms of management of nature and the low level of ecological society consciousness have led to the significant deterioration of environment state in Ukraine, excessive pollution of waters, air, and soil, accumulation of a large number of waste products. Besides, the produce as a result of such enterprises’ production affects consumers’ health badly. This causes the need to develop theory and methodology of production ecological quality accounting. The problem of quality is the most important factor of increasing of life level, economic, social and ecological security in market economy. This, the current research aims to formulate the essence of concept “ecological quality of production” The research determines that ecological quality is characterized by the following main 6 aspects: social, technical, legal, economic, aesthetic and ecological. If one of these six aspects does not work, we cannot speak about ecological quality of a certain commodity. Many various factors influence upon the level of ecological quality of products and services. According to their contents and directions, they can be united into the following main 6 groups: technical, organizational, economic and social, ecological and aesthetic and legal. The article determines the directions of production ecological quality increasing.

  1. Application of Portfolio Theory in Recovery Planning for Pacific Salmon.

    Science.gov (United States)

    Ecological applications of portfolio theory demonstrate the utility of this analytical framework for understanding the stability of commercial and indigenous Pacific Salmon fisheries. Portfolio theory also has the potential to aid in recovery planning for threatened and endangere...

  2. [Applied ecology: retrospect and prospect].

    Science.gov (United States)

    He, Xingyuan; Zeng, Dehui

    2004-10-01

    Applied ecology is evolved into a principal part of modern ecology that rapidly develops. The major stimulus for the development of applied ecology roots in seeking the solutions for the problems of human populations, resources and environments. Through four decades, the science of applied ecology has been becoming a huge group of disciplines. The future for the applied ecology should concern more with human-influenced and managed ecosystems, and acknowledge humans as the components of ecosystems. Nowadays and in future, the top-priorities in applied ecology should include following fields: sustainable ecosystems and biosphere, ecosystem services and ecological design, ecological assessment of genetically modified organisms, ecology of biological invasions, epidemical ecology, ecological forecasting, ecological process and its control. The authors believe that the comprehensive and active research hotspots coupled some new traits would occur around these fields in foreseeable future.

  3. Deliberative Ecological Economics for Sustainability Governance

    Directory of Open Access Journals (Sweden)

    Richard B. Howarth

    2010-10-01

    Full Text Available We discuss the recent emergence of ‘deliberative ecological economics’, a field that highlights the potential of deliberation for improving environmental governance. We locate the emergence of this literature in the long concern in ecological economics over the policy implications of limited views of human action and its encounter with deliberative democracy scholarship and the model of communicative rationality as an alternative to utilitarianism. Considering criticisms over methods used and the focus of research in deliberative decision-making, we put forward a research agenda for deliberative ecological economics. Given the promising potential of deliberative processes for improving the effectiveness and legitimacy of environmental decision-making, work in this area could help advance both theory and practice in environmental governance.

  4. TINNITUS WHAT AND WHERE: AN ECOLOGICAL FRAMEWORK

    Directory of Open Access Journals (Sweden)

    Grant Donald Searchfield

    2014-12-01

    Full Text Available Tinnitus is an interaction of the environment, cognition and plasticity. The connection between the individual with tinnitus and their world seldom receives attention in neurophysiological research. As well as changes in cell excitability, an individual’s culture and beliefs, work and social environs may all influence how tinnitus is perceived. In this review an ecological framework for current neurophysiological evidence is considered. The model defines tinnitus as the perception of an auditory object in the absence of an acoustic event. It is hypothesized that following deafferentation: adaptive feature extraction, schema and semantic object formation processes lead to tinnitus in a manner predicted by Adaptation Level Theory (1, 2. Evidence from physiological studies are compared to the tenants of the proposed ecological model. The consideration of diverse events within an ecological context may unite seemingly disparate neurophysiological models.

  5. Individual-based modeling of ecological and evolutionary processes

    Science.gov (United States)

    DeAngelis, Donald L.; Mooij, Wolf M.

    2005-01-01

    Individual-based models (IBMs) allow the explicit inclusion of individual variation in greater detail than do classical differential-equation and difference-equation models. Inclusion of such variation is important for continued progress in ecological and evolutionary theory. We provide a conceptual basis for IBMs by describing five major types of individual variation in IBMs: spatial, ontogenetic, phenotypic, cognitive, and genetic. IBMs are now used in almost all subfields of ecology and evolutionary biology. We map those subfields and look more closely at selected key papers on fish recruitment, forest dynamics, sympatric speciation, metapopulation dynamics, maintenance of diversity, and species conservation. Theorists are currently divided on whether IBMs represent only a practical tool for extending classical theory to more complex situations, or whether individual-based theory represents a radically new research program. We feel that the tension between these two poles of thinking can be a source of creativity in ecology and evolutionary theory.

  6. What is CPH Theory?

    DEFF Research Database (Denmark)

    Javadi, Hossein; Forouzbakhsh, Farshid; Daei Kasmaei, Hamed

    2016-01-01

    There are various theories in physics, but nature is unique. This is not nature's problem that we have various theories; nature obeys simple and unique law. We should improve our theories. Universal constancy of the speed of light undergoes the question whether the limit on the light speed...... is the mechanism of increasing in the photon energy that causes increase in its frequency growth? So, in CPH theory (Creative particles of Higgs Theory), it has been attempted to scrutinize the interface between classical mechanics, relativity and quantum mechanics through a novel approach to the established...... physical events. Emphasizing on these phenomena and presenting the relation between photon's energy and frequency, CPH Theory is to draw attention on the importance of constancy of speed in relation to the mass structure which will be scrutinized in reviewing relativistic Newton's second law. The results...

  7. An introduction to central simple algebras and their applications to wireless communication

    CERN Document Server

    Berhuy, Gre�gory

    2013-01-01

    Central simple algebras arise naturally in many areas of mathematics. They are closely connected with ring theory, but are also important in representation theory, algebraic geometry and number theory. Recently, surprising applications of the theory of central simple algebras have arisen in the context of coding for wireless communication. The exposition in the book takes advantage of this serendipity, presenting an introduction to the theory of central simple algebras intertwined with its applications to coding theory. Many results or constructions from the standard theory are presented in classical form, but with a focus on explicit techniques and examples, often from coding theory. Topics covered include quaternion algebras, splitting fields, the Skolem-Noether Theorem, the Brauer group, crossed products, cyclic algebras and algebras with a unitary involution. Code constructions give the opportunity for many examples and explicit computations. This book provides an introduction to the theory of central alg...

  8. Education in ecology

    International Nuclear Information System (INIS)

    Marek, R.

    1993-01-01

    It is not enough to convey knowledge, insights and attitudes if education in ecology is to have fruitful effects. Space and opportunity for action and creativity must be provided in addition. This includes personal consumer habits (eating, transport, hygiene, leisure activities etc.); an individual workplace - in this case school - that can be shaped according to ecological needs. Beyond this, ecological maturation should not be confined to, but should transcend school, for instance in youth groups, citizens' committees, political parties. If school does not inspire action - including action outside school -then education in ecology could be smothered by the Midas effect, where all life is reduced to material, to the curriculum in this case. This book presents ecological projects that have been tried at schools. They aim at an education in ecology that is oriented to the pupil and open to experience. They could be an incentive for colleagues to conduct similar projects at their schools. The projects work from the pupils' own experience and aim at concrete action and activities in his or her own environment. They should encourage teachers to venture outside the classroom with the pupils and teach ecology where it takes place. (orig.) [de

  9. A Simple Spectral Observer

    Directory of Open Access Journals (Sweden)

    Lizeth Torres

    2018-05-01

    Full Text Available The principal aim of a spectral observer is twofold: the reconstruction of a signal of time via state estimation and the decomposition of such a signal into the frequencies that make it up. A spectral observer can be catalogued as an online algorithm for time-frequency analysis because is a method that can compute on the fly the Fourier transform (FT of a signal, without having the entire signal available from the start. In this regard, this paper presents a novel spectral observer with an adjustable constant gain for reconstructing a given signal by means of the recursive identification of the coefficients of a Fourier series. The reconstruction or estimation of a signal in the context of this work means to find the coefficients of a linear combination of sines a cosines that fits a signal such that it can be reproduced. The design procedure of the spectral observer is presented along with the following applications: (1 the reconstruction of a simple periodical signal, (2 the approximation of both a square and a triangular signal, (3 the edge detection in signals by using the Fourier coefficients, (4 the fitting of the historical Bitcoin market data from 1 December 2014 to 8 January 2018 and (5 the estimation of a input force acting upon a Duffing oscillator. To round out this paper, we present a detailed discussion about the results of the applications as well as a comparative analysis of the proposed spectral observer vis-à-vis the Short Time Fourier Transform (STFT, which is a well-known method for time-frequency analysis.

  10. Simple autonomous Mars walker

    Science.gov (United States)

    Larimer, Stanley J.; Lisec, Thomas R.; Spiessbach, Andrew J.

    1989-01-01

    Under a contract with NASA's Jet Propulsion Laboratory, Martin Marietta has developed several alternative rover concepts for unmanned exploration of the planet Mars. One of those concepts, the 'Walking Beam', is the subject of this paper. This concept was developed with the goal of achieving many of the capabilities of more sophisticated articulated-leg walkers with a much simpler, more robust, less computationally demanding and more power efficient design. It consists of two large-base tripods nested one within the other which alternately translate with respect to each other along a 5-meter beam to propel the vehicle. The semiautonomous navigation system relies on terrain geometry sensors and tacticle feedback from each foot to autonomously select a path which avoids hazards along a route designated from earth. Both mobility and navigation features of this concept are discussed including a top-level description of the vehicle's physical characteristics, deployment strategy, mobility elements, sensor suite, theory of operation, navigation and control processes, and estimated performance.

  11. Simple de Sitter solutions

    International Nuclear Information System (INIS)

    Silverstein, Eva

    2008-01-01

    We present a framework for de Sitter model building in type IIA string theory, illustrated with specific examples. We find metastable de Sitter (dS) minima of the potential for moduli obtained from a compactification on a product of two nil three-manifolds (which have negative scalar curvature) combined with orientifolds, branes, fractional Chern-Simons forms, and fluxes. As a discrete quantum number is taken large, the curvature, field strengths, inverse volume, and four-dimensional string coupling become parametrically small, and the de Sitter Hubble scale can be tuned parametrically smaller than the scales of the moduli, Kaluza Klein (KK), and winding mode masses. A subtle point in the construction is that although the curvature remains consistently weak, the circle fibers of the nilmanifolds become very small in this limit (though this is avoided in illustrative solutions at modest values of the parameters). In the simplest version of the construction, the heaviest moduli masses are parametrically of the same order as the lightest KK and winding masses. However, we provide a method for separating these marginally overlapping scales, and more generally the underlying supersymmetry of the model protects against large corrections to the low-energy moduli potential

  12. A theory of piezoelectric laminates

    International Nuclear Information System (INIS)

    Giangreco, E.

    1997-01-01

    A theory of piezoelectric laminates is rationally derived from the three-dimensional Voigt theory of piezoelectricity. The present theory is a generalization to piezoelectric laminates of the Reissner-Mindlin-type layer-wise theory of elastic laminates. Both a differential formulation and a variational formulation of the piezoelectric laminate problem are presented. The proposed theory is adopted in the analysis of simple problems, in order to verify its effectiveness. The results it provides turn out to be in good agreement with the results supplied by the Voigt theory of piezoelectricity

  13. Topological field theories and duality

    International Nuclear Information System (INIS)

    Stephany, J.; Universidad Simon Bolivar, Caracas

    1996-05-01

    Topologically non trivial effects appearing in the discussion of duality transformations in higher genus manifold are discussed in a simple example, and their relation with the properties of Topological Field Theories is established. (author). 16 refs

  14. Game theory and fish wars

    DEFF Research Database (Denmark)

    Jensen, Frank; Frost, Hans Staby; Thøgersen, Thomas Talund

    2015-01-01

    of the mackerel crisis is based on a statistical estimation of relevant functional relations, and the behavior of the players is explained using a fully specified empirical model. Simple, non-cooperative game theory shows that all players have an incentive to act non-cooperatively, a result that is robust......Simple non-cooperative and cooperative game theory is used to explore the crisis involving the European Union (EU), Norway, Iceland and the Faroe Islands regarding the size and relative allocation of total allowable catches (TACs) in the mackerel fishery in the Northeast Atlantic. The analysis...... to changes in basic assumptions regarding demand and cost functions. Thus, using the estimated parameters and functions, simple, non-cooperative game theory cannot explain the cooperative behavior of EU and Norway during the mackerel crisis. Simple cooperative game theory shows that no player has...

  15. Recent Developments in Ecological Economics

    DEFF Research Database (Denmark)

    Reader with published articles within the field of ecological economics, mostly from 1997 - 2007......Reader with published articles within the field of ecological economics, mostly from 1997 - 2007...

  16. Options theory

    International Nuclear Information System (INIS)

    Markland, J.T.

    1992-01-01

    Techniques used in conventional project appraisal are mathematically very simple in comparison to those used in reservoir modelling, and in the geosciences. Clearly it would be possible to value assets in mathematically more sophisticated ways if it were meaningful and worthwhile so to do. The DCf approach in common use has recognized limitations; the inability to select a meaningful discount rate being particularly significant. Financial Theory has advanced enormously over the last few years, along with computational techniques, and methods are beginning to appear which may change the way we do project evaluations in practice. The starting point for all of this was a paper by Black and Scholes, which asserts that almost all corporate liabilities can be viewed as options of varying degrees of complexity. Although the financial presentation may be unfamiliar to engineers and geoscientists, some of the concepts used will not be. This paper outlines, in plain English, the basis of option pricing theory for assessing the market value of a project. it also attempts to assess the future role of this type of approach in practical Petroleum Exploration and Engineering economics. Reference is made to relevant published Natural Resource literature

  17. Quantitative plant ecology

    DEFF Research Database (Denmark)

    Damgaard, Christian

    2014-01-01

    This e-book is written in the Wolfram' CDF format (download free CDF player from Wolfram.com) The objective of this e-book is to introduce the population ecological concepts for measuring and predicting the ecological success of plant species. This will be done by focusing on the measurement...... and statistical modelling of plant species abundance and the relevant ecological processes that control species abundance. The focus on statistical modelling and likelihood function based methods also means that more algorithm based methods, e.g. ordination techniques and boosted regression tress...

  18. Inferring biodiversity maintenance mechanisms from ecological pattern

    Science.gov (United States)

    Ostling, Annette

    Among a set of competitors for a single common resource, the best will simply exclude the others. Yet in nature we can see astounding diversity of competing species. Do close similarities in species' response to the local environment primarily explain their coexistence? Or is this diversity possible because of differences between species that stabilize their coexistence? And if so, what particular differences between species are important in particular communities? Some ecological communities lend themselves to experimental manipulation to begin to answer these questions. Yet for many other communities, such as tree species in forests, the logistical hurdles to this approach are daunting. Faster progress could be made in ecology if insight into biodiversity maintenance mechanisms could be gained from patterns exhibited in local ecological communities, such as how coexisting species are distributed in their ecological traits and relative abundance. Hurdles that we need to overcome to be able to gain such insight include: 1) further developing neutral theory, a quantitative process-based null model of community pattern resulting when species similarities are what allow their coexistence, and 2) better understanding what patterns to expect when species differences dominate instead, particularly in the context of stochasticity and immigration. I will describe our ongoing research to overcome these hurdles, to provide better tools for analyzing observed pattern. National Science Foundation Advancing Theory in Biology Grant 1038678, Danish National Research Foundation Grant DNRF 96 for the Center of Macroecology, Evolution and Climate.

  19. Man - environment - innovations. Are economy and ecology opposite notions?

    International Nuclear Information System (INIS)

    Fritsch, B.

    1994-01-01

    This book has the aim to describe complex economic and ecological problems in simple language. So, the most pressing challenges of our time, for instance population growth and age structure, energy, urbanization, raw materials and the environment, change of values, growing environmental awareness and technology risk assessment are outlined. Different concepts for solving the ecological problems with economically reasonable premises are described and evaluated. The analysis is followed by concrete calls for changes in the political boundary conditions in the fields of environmental, ecological and economic policy. (orig.) [de

  20. Is the world simple or complicated

    CERN Document Server

    Barrow, John D

    1998-01-01

    Stop some particle physicists in the street and they will soon be trying to persuade you that the world is altogether simple and symmetrical. But stop a biologist, an economist, or a social scientist and they will tell you quite the opposite: the world is a higgledy-piggledy collection of complexities that owes little to symmetry and displays precious little simplicity. So who is right : is the world really complicated or is it simple ? We shall look at the reasoning that leads to these different conclusions, show why we got different answers to our question, and look at some of the recent developments that have taken place in the study of systems from sand-piles to music on the border between order and chaos. We shall also look at some of the connections between our aesthetic sensibilities and the structure of scientific theories.

  1. Ecological advice for the global fisher crisis.

    Science.gov (United States)

    Roberts, C M

    1997-01-01

    Fisheries science was the precursor of population ecology and continues to contribute important theoretical advances. Despite this, fishery scientists have a poor record for applying their insights to real-world fisheries management. Is there a gulf between theory and application or does the high variability inherent in fish populations and complexity of multispecies fisheries demand a different approach to management? Perhaps the solution to the world fisheries crisis is obvious after all?

  2. Life after Newton: an ecological metaphysic.

    Science.gov (United States)

    Ulanowicz, R E

    1999-05-01

    Ecology may indeed be 'deep', as some have maintained, but perhaps much of the mystery surrounding it owes more simply to the dissonance between ecological notions and the fundamentals of the modern synthesis. Comparison of the axioms supporting the Newtonian world view with those underlying the organicist and stochastic metaphors that motivate much of ecosystems science reveals strong disagreements--especially regarding the nature of the causes of events and the scalar domains over which these causes can operate. The late Karl Popper held that the causal closure forced by our mechanical perspective on nature frustrates our attempts to achieve an 'evolutionary theory of knowledge.' He suggested that the Newtonian concept of 'force' must be generalized to encompass the contingencies that arise in evolutionary processes. His reformulation of force as 'propensity' leads quite naturally to a generalization of Newton's laws for ecology. The revised tenets appear, however, to exhibit more scope and allow for change to arise from within a system. Although Newton's laws survive (albeit in altered form) within a coalescing ecological metaphysic, the axioms that Enlightenment thinkers appended to Newton's work seem ill-suited for ecology and perhaps should yield to a new and coherent set of assumptions on how to view the processes of nature.

  3. Social-ecological resilience and law

    Science.gov (United States)

    Garmestani, Ahjond S.; Allen, Craig R.

    2014-01-01

    Environmental law envisions ecological systems as existing in an equilibrium state, reinforcing a rigid legal framework unable to absorb rapid environmental changes and innovations in sustainability. For the past four decades, “resilience theory,” which embraces uncertainty and nonlinear dynamics in complex adaptive systems, has provided a robust, invaluable foundation for sound environmental management. Reforming American law to incorporate this knowledge is the key to sustainability. This volume features top legal and resilience scholars speaking on resilience theory and its legal applications to climate change, biodiversity, national parks, and water law.

  4. [Darwinism as a constraint of ecological pluralism].

    Science.gov (United States)

    Giliarov, A M

    2003-01-01

    In his respond to critical remarks of Mirkin (2003), the author claims that pluralism in ecology is not only its strength but also a weakness. Contemporary ecology became less pluralistic and this can be considered as good sign of maturing science. Ecological pluralism can be exemplified by the coexistence in 1920-30s of two different approaches to plant community: that of Frederic Clements in USA and that of Josias Braun-Blanquet in France. However the way to progress in this branch of ecology was paved rather by heretical ideas of Henry Gleason in USA and Ramensky in Russia (both authors independently developed non-holistic view of community as an assemblage of individualistically distributed species) than by "peaceful" coexistence of well-established schools, representatives of which tried not to interfere into argumentation of each other. Notable success in ecology of last decades was connected with several new methodologies, e.g. macroecology that concerned large scale of space and time. However Darwinism in its attempt to explain the order of nature referring to its origin remains the most universal and fruitful methodology of ecology. The success of Darwinism in ecology is understandable because this generalizing theory is based on the same universal principles that underlie the survival of any population. Ecologists and evolutionary biologists trying to understand various natural patterns actually deal with the same fundamental laws, i.e. exponential population growth, limitation of this growth by resource shortage and/or press of predators, the existence of individual variability in survival, etc.

  5. Challenges of ecological restoration

    DEFF Research Database (Denmark)

    Halme, Panu; Allen, Katherine A.; Aunins, Ainars

    2013-01-01

    we introduce northern forests as an ecosystem, discuss the historical and recent human impact and provide a brief status report on the ecological restoration projects and research already conducted there. Based on this discussion, we argue that before any restoration actions commence, the ecology......The alarming rate of ecosystem degradation has raised the need for ecological restoration throughout different biomes and continents. North European forests may appear as one of the least vulnerable ecosystems from a global perspective, since forest cover is not rapidly decreasing and many...... on Biological Diversity. Several northern countries are now taking up this challenge by restoring forest biodiversity with increasing intensity. The ecology and biodiversity of boreal forests are relatively well understood making them a good model for restoration activities in many other forest ecosystems. Here...

  6. Ecological Provinces of Minnesota

    Data.gov (United States)

    Minnesota Department of Natural Resources — This coverage provides information for the first level of the Ecological Classification System. The boundaries of the polygons of this coverage were derived from...

  7. Market Squid Ecology Dataset

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains ecological information collected on the major adult spawning and juvenile habitats of market squid off California and the US Pacific Northwest....

  8. Ecological risk estimation

    International Nuclear Information System (INIS)

    Bartell, S.M.; Gardner, R.H.; O'Neill, R.V.

    1992-01-01

    Ecological risk assessment, the process that evaluates the likelihood that adverse ecological effects may occur or are occurring as a result of exposure to one or more stressors, is being developed by the US EPA as a tool for decision making. This book presents one approach to risk assessment-that of applying laboratory toxicity data within an ecosystem model to predict the potential ecological consequences of toxic chemicals. Both Standard Water Column Model (SWACOM), using zooplankton and fish, and Monte Carlo simulations are discussed in detail, along with quantitative explanations for many responses. Simplifying assumptions are explicitly presented. The final chapter discusses strengths, weaknesses, and future directions of the approach. The book is appropriate for anyone who does or uses ecological risk assessment methodologies

  9. Green Turtle Trophic Ecology

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — SWFSC is currently conducting a study of green sea turtle (Chelonia mydas) trophic ecology in the eastern Pacific. Tissue samples and stable carbon and stable...

  10. Ecological Sections of Minnesota

    Data.gov (United States)

    Minnesota Department of Natural Resources — This coverage provides information for the second level of the Ecological Classification System. The boundaries of the polygons of this coverage were derived from...

  11. The French ecological movement

    International Nuclear Information System (INIS)

    Sansen, Bernard

    1977-01-01

    The analysis of the ecological Movement in France is presented: its organisation, its topics, its position with respect to the main political trends. The accent is put in particular on the antinuclear contestation [fr

  12. Embracing uncertainty in applied ecology.

    Science.gov (United States)

    Milner-Gulland, E J; Shea, K

    2017-12-01

    Applied ecologists often face uncertainty that hinders effective decision-making.Common traps that may catch the unwary are: ignoring uncertainty, acknowledging uncertainty but ploughing on, focussing on trivial uncertainties, believing your models, and unclear objectives.We integrate research insights and examples from a wide range of applied ecological fields to illustrate advances that are generally underused, but could facilitate ecologists' ability to plan and execute research to support management.Recommended approaches to avoid uncertainty traps are: embracing models, using decision theory, using models more effectively, thinking experimentally, and being realistic about uncertainty. Synthesis and applications . Applied ecologists can become more effective at informing management by using approaches that explicitly take account of uncertainty.

  13. Hofmeister series of ions: A simple theory of a not so simple reality

    Czech Academy of Sciences Publication Activity Database

    Jungwirth, Pavel

    2013-01-01

    Roč. 4, č. 24 (2013), s. 4258-4259 ISSN 1948-7185 Institutional support: RVO:61388963 Keywords : Hofmeister series * ions * proteins Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 6.687, year: 2013

  14. Anorthosites: Classification, mythology, trivia, and a simple unified theory

    Science.gov (United States)

    Ashwal, Lewis D.

    1988-01-01

    An overview was presented of anorthosites. They were classified into six types: (1) Archean megacrystic, (2) Proterozoic massif-type, (3) stratiform, (4) oceanic, (5) inclusions, and (6) extraterrestrial. Some of the anorthosite mythology was discussed, such as the existence of a distinct, catastrophic anorthosite event in the late Proterozoic, the misconception that anorthosite is a major constituent of the lower continental crust, and the misconception that Archean anorthosites represent metamorphosed equivalents of mafic layered intrusions such as Bushveld or Stillwater. A general statement was offered about the origin of all anorthosites: They are cumulates of plagioclase from mantle-derived basaltic magmas.

  15. A Simple Economic Theory of Skill Accumulation and Schooling Decisions

    OpenAIRE

    William Blankenau; Gabriele Camera

    2006-01-01

    We propose a model of schooling that can account for the observed heterogeneity in workers' productivity and educational attainment. Identical unskilled agents can get a degree at a cost, but becoming skilled entails an additional unobservable effort cost. Individual labor can then be used as an input in pairwise production matches. Two factors affect students' desire to build human capital: degrees imperfectly signal productivity, and contract imperfections generate holdup problems. Multiple...

  16. A simple remark on three dimensional gauge theories

    International Nuclear Information System (INIS)

    Lemes, V.E.R.; Linhares de Jesus, C.; Sasaki, C.A.G.; Sorella, S.P.; Vilar, L.C.Q.; Ventura, O.S.

    1997-08-01

    Classical three dimensional Yang-Mills is seen to be related to the topological Chern-Simons term through a nonlinear but fully local and covariant gauge field redefinition. A classical recursive cohomological argument is proved. (author)

  17. Marine Ecological Environment Management Based on Ecological Compensation Mechanisms

    Directory of Open Access Journals (Sweden)

    Qunzhen Qu

    2016-12-01

    Full Text Available The level of marine environmental management is a key factor in the successful implementation of marine power strategies. The improvement in management levels of marine environments requires innovation in marine management. In other words, the transformation of marine environmental management into marine ecological environment management must be done in order to achieve sustainable development of the marine economy. As an environmental economic policy that combines both administrative and market measures, ecological compensation mechanisms have significant advantages in marine ecological environment management. Based on the study of the current development of ecological compensation mechanisms in China, through the analysis of the connotation of marine ecological civilization, existing marine ecological protection practices and marine environmental management methods, this paper posits that the current marine ecological environment management in China should be established on the basis of ecological compensation mechanisms. At present, a lack of laws and regulations for overall marine ecological environment management is the key factor restricting the practice of marine ecological environment management. Therefore, it is necessary to explore the current path of marine ecological environment management in China from the perspective of the construction of legal system of ecological compensation law, the establishment of ecological compensation fees, ecological taxes and ecological compensation fund systems, and the clear status for a marine ecological management and supervision body.

  18. Biosemiotics and ecological monitoring

    DEFF Research Database (Denmark)

    Bruni, Luis Emilio

    2001-01-01

    of the qualitative and relational aspects that can only be grasped by considering the semiotic networks operative in complex ecological and cultural systems. In this paper, it is suggested that a biosemiotic approach to ecology may prove useful for the modelling process, which in turn will allow the construction...... of meaningful monitoring systems. It is also contended that a biosemiotic approach may also serve to better integrate our understanding and monitoring of ecosystems into the cultural process of searching for (human) sustainability....

  19. Sraffa and ecological economics

    OpenAIRE

    Verger, Yoann

    2015-01-01

    References to Sraffa and to the neo-Ricardian school is something quite customary in ecological economics. By looking at contributions in this area since the beginning of ecological economics and at contributions on environmental problem from the neo-Ricardian school, we see that a connection between both school still has to be made. This connection should be articulated around the initial aim of Sraffa: to develop a new paradigm, competing against the neoclassical one. Only then it will be p...

  20. Translational ecology for hydrogeology.

    Science.gov (United States)

    Schlesinger, William H

    2013-01-01

    Translational ecology--a special discipline aimed to improve the accessibility of science to policy makers--will help hydrogeologists contribute to the solution of pressing environmental problems. Patterned after translational medicine, translational ecology is a partnership to ensure that the right science gets done in a timely fashion, so that it can be communicated to those who need it. © 2013, National Ground Water Association.

  1. Simple models of equilibrium and nonequilibrium phenomena

    International Nuclear Information System (INIS)

    Lebowitz, J.L.

    1987-01-01

    This volume consists of two chapters of particular interest to researchers in the field of statistical mechanics. The first chapter is based on the premise that the best way to understand the qualitative properties that characterize many-body (i.e. macroscopic) systems is to study 'a number of the more significant model systems which, at least in principle are susceptible of complete analysis'. The second chapter deals exclusively with nonequilibrium phenomena. It reviews the theory of fluctuations in open systems to which they have made important contributions. Simple but interesting model examples are emphasised

  2. Communication: Simple liquids' high-density viscosity

    Science.gov (United States)

    Costigliola, Lorenzo; Pedersen, Ulf R.; Heyes, David M.; Schrøder, Thomas B.; Dyre, Jeppe C.

    2018-02-01

    This paper argues that the viscosity of simple fluids at densities above that of the triple point is a specific function of temperature relative to the freezing temperature at the density in question. The proposed viscosity expression, which is arrived at in part by reference to the isomorph theory of systems with hidden scale invariance, describes computer simulations of the Lennard-Jones system as well as argon and methane experimental data and simulation results for an effective-pair-potential model of liquid sodium.

  3. Communication: Simple liquids' high-density viscosity.

    Science.gov (United States)

    Costigliola, Lorenzo; Pedersen, Ulf R; Heyes, David M; Schrøder, Thomas B; Dyre, Jeppe C

    2018-02-28

    This paper argues that the viscosity of simple fluids at densities above that of the triple point is a specific function of temperature relative to the freezing temperature at the density in question. The proposed viscosity expression, which is arrived at in part by reference to the isomorph theory of systems with hidden scale invariance, describes computer simulations of the Lennard-Jones system as well as argon and methane experimental data and simulation results for an effective-pair-potential model of liquid sodium.

  4. Using neutral theory to reveal the contribution of meta-community processes to assembly in complex landscapes

    Directory of Open Access Journals (Sweden)

    Dominique Gravel

    2014-04-01

    Full Text Available The metacommunity perspective appears as an appropriate conceptual framework to make ecology more predictive. It is particularly relevant to limnology, where exchanges of organisms and nutrients affect community and ecosystem properties from the local to the regional scales. The recent development of neutral theory appears as a step back in that direction because of the assumption of ecological equivalence and the absence of any effect of the environment on community organization. A remarkable strength of neutral theory is nonetheless to provide a general theory of diversity that accounts for a wide range of empirical observations. In this paper, we argue that neutral theory can be useful to understand the impact of dispersal on community assembly in landscapes of various complexities. Our analysis focus on spatially explicit landscapes conceptualized as networks of local communities (e.g., lakes connected to each other by dispersal channels (e.g., rivers. The main objective of the paper is to use neutral theory to stress the importance of landscape structure on the distribution of diversity. We refer to the landscape organization as a spatial contingency that could potentially affect the coexistence mechanisms at play. We briefly review the main approaches to describe spatial networks and describe three simple toy models of metacommunity dynamics. We take this opportunity to review their assumptions and main predictions. We then conduct simulations of these models to reveal with simple examples the impact of spatial network structure on diversity distribution. The simulation results show that competitive interactions buffer the potential impact of landscape structure. The strongest relationship between node position in the landscape and species richness was observed for the patch dynamics model without any interactions. On the other hand, strong and unequal competitive interactions minimized the effect of node position. We conclude that the

  5. Parafermionic conformal field theory

    International Nuclear Information System (INIS)

    Kurak, V.

    1989-09-01

    Conformal parafermionic field theories are reviewed with emphasis on the computation of their OPE estructure constants. It is presented a simple computational of these for the Z(N) parafermions, unveilling their Lie algebra content. (A.C.A.S.) [pt

  6. Modular invariants from simple currents. An explicit proof

    International Nuclear Information System (INIS)

    Schellekens, A.N.; Yankielowicz, S.

    1989-01-01

    In a previous paper an orbifold construction was used to demonstrate that the existence of primary fields with simple fusion rules in a conformal field theory implies the existence of non-diagonal modular invariant partition functions. Here we present a direct and explicit proof of modular invariance, which also covers a few cases that could not be obtained with the orbifold method. We also give a very simple general formula for the modular matrix M. (orig.)

  7. a simple a simple excitation control excitation control excitation

    African Journals Online (AJOL)

    eobe

    field voltages determined follow a simple quadratic relationship that offer a very simple control scheme, dependent on only the stator current. Keywords: saturated reactances, no-load field voltage, excitation control, synchronous generators. 1. Introduction. Introduction. Introduction. The commonest generator in use today is ...

  8. Ecology, Capital, and the Nature of Our Times: Accumulation & Crisis in the Capitalist World-Ecology

    Directory of Open Access Journals (Sweden)

    Jason W. Moore

    2015-08-01

    Full Text Available In this essay, I elaborate the possibilities for a unified theory of historical capitalism - one thatviews the accumulation of capital and the production of nature (humans included! asdialectically constituted. In this view, the modern world-system is a capitalist world-ecology, aworld-historical matrix of human- and extra-human nature premised on endless commodification.The essay is organized in three movements. I begin by arguing for a reading of modernity's"interdependent master processes" (Tilly as irreducibly socio-ecological. Capitalism does notdevelop upon global nature so much as it emerges through the messy and contingent relations ofhumans with the rest of nature. Second, the paper engages Giovanni Arrighi's handling of time,space, and accumulation in The Long Twentieth Century. I highlight Arrighi 's arguments for a"structurally variant" capitalism, and the theory of organizational revolutions, as fruitful ways toconstruct a theory of capitalism as world-ecology. I conclude with a theory of accumulation andits crises as world-ecological process, building out from Marx's "general law" ofunderproduction. Historically, capitalism has been shaped by a dialectic of underproduction (toofew inputs and overproduction (too many commodities. Today, capitalism is poised for a re-emergence of underproduction crises, characterized by the insufficient flow of cheap food, fuel,labor, and energy to the productive circuit of capital. Far from the straightforward expression of"overshoot" and "peak everything," the likely resurgence of underproduction crises is anexpression of capitalism's longue duree tendency to undermine its conditions of reproduction.The world-ecological limit of capital, in other words, is capital itself

  9. Trophic dynamics of a simple model ecosystem.

    Science.gov (United States)

    Bell, Graham; Fortier-Dubois, Étienne

    2017-09-13

    We have constructed a model of community dynamics that is simple enough to enumerate all possible food webs, yet complex enough to represent a wide range of ecological processes. We use the transition matrix to predict the outcome of succession and then investigate how the transition probabilities are governed by resource supply and immigration. Low-input regimes lead to simple communities whereas trophically complex communities develop when there is an adequate supply of both resources and immigrants. Our interpretation of trophic dynamics in complex communities hinges on a new principle of mutual replenishment, defined as the reciprocal alternation of state in a pair of communities linked by the invasion and extinction of a shared species. Such neutral couples are the outcome of succession under local dispersal and imply that food webs will often be made up of suites of trophically equivalent species. When immigrants arrive from an external pool of fixed composition a similar principle predicts a dynamic core of webs constituting a neutral interchange network, although communities may express an extensive range of other webs whose membership is only in part predictable. The food web is not in general predictable from whole-community properties such as productivity or stability, although it may profoundly influence these properties. © 2017 The Author(s).

  10. Benefits of ecological engineering practices

    NARCIS (Netherlands)

    Van den Boomen, R.; Chaudhuri, N.; Heeb, J.; Jenssen, P.; Kalin, M.; Schönborn, A.; Brüll, A.; Van Bohemen, H.; Costanza, R.; Mitsch, W.J.

    2011-01-01

    With the intention to further promote the field of ecological engineering and the solutions it provides, a workshop on “Benefits of Ecological Engineering Practices” was held 3 Dec 2009. It was conducted by the International Ecological Engineering Society in Paris at the conference “Ecological

  11. Is simple nephrectomy truly simple? Comparison with the radical alternative.

    Science.gov (United States)

    Connolly, S S; O'Brien, M Frank; Kunni, I M; Phelan, E; Conroy, R; Thornhill, J A; Grainger, R

    2011-03-01

    The Oxford English dictionary defines the term "simple" as "easily done" and "uncomplicated". We tested the validity of this terminology in relation to open nephrectomy surgery. Retrospective review of 215 patients undergoing open, simple (n = 89) or radical (n = 126) nephrectomy in a single university-affiliated institution between 1998 and 2002. Operative time (OT), estimated blood loss (EBL), operative complications (OC) and length of stay in hospital (LOS) were analysed. Statistical analysis employed Fisher's exact test and Stata Release 8.2. Simple nephrectomy was associated with shorter OT (mean 126 vs. 144 min; p = 0.002), reduced EBL (mean 729 vs. 859 cc; p = 0.472), lower OC (9 vs. 17%; 0.087), and more brief LOS (mean 6 vs. 8 days; p < 0.001). All parameters suggest favourable outcome for the simple nephrectomy group, supporting the use of this terminology. This implies "simple" nephrectomies are truly easier to perform with less complication than their radical counterpart.

  12. Equilibria of perceptrons for simple contingency problems.

    Science.gov (United States)

    Dawson, Michael R W; Dupuis, Brian

    2012-08-01

    The contingency between cues and outcomes is fundamentally important to theories of causal reasoning and to theories of associative learning. Researchers have computed the equilibria of Rescorla-Wagner models for a variety of contingency problems, and have used these equilibria to identify situations in which the Rescorla-Wagner model is consistent, or inconsistent, with normative models of contingency. Mathematical analyses that directly compare artificial neural networks to contingency theory have not been performed, because of the assumed equivalence between the Rescorla-Wagner learning rule and the delta rule training of artificial neural networks. However, recent results indicate that this equivalence is not as straightforward as typically assumed, suggesting a strong need for mathematical accounts of how networks deal with contingency problems. One such analysis is presented here, where it is proven that the structure of the equilibrium for a simple network trained on a basic contingency problem is quite different from the structure of the equilibrium for a Rescorla-Wagner model faced with the same problem. However, these structural differences lead to functionally equivalent behavior. The implications of this result for the relationships between associative learning, contingency theory, and connectionism are discussed.

  13. 基于社会-生态系统的沙漠化逆转过程脆弱性评价指标体系%An evaluation index system of vulnerability of the desertification reversion process based on the socio-ecological systems theory

    Institute of Scientific and Technical Information of China (English)

    王娅; 周立华; 魏轩

    2018-01-01

    Sandy desertification is one of the most severe ecological and environmental problems worldwide.Desertification reversion,as the reverse process of desertification expansion,has some instability and vulnerability due to disturbances by numerous socio-ecological factors.We call this phenomenon vulnerability of the desertification reversion process,and define it as the possibility and tendency of a reversion trend decline or reversal.Socio-ecological systems theory is a new form of ecological systems research.Based on this theory,we selected the driving-pressure-status-impact-response (DPSIR) framework and a typical reversed desertification area in Yanchi County as the study area.In this area,human activities have obviously interfered with natural processes and the expansion and reversal of desertification contrast sharply.We constructed an evaluation index system to assess the vulnerability of the desertification reversion process.This system includes four levels,five groups,and forty-one concrete indexes,including a moisture index,an ecological govemance index,and sandy proportion.Finally,we explore the logical causality between drivers,pressure,status,impact,response,meanwhile discuss the quantitative calculation method of vulnerability.The objective of this study was to scientifically assess the vulnerability of the desertification reversion process,and to provide support and a scientific basis to make decisions,manage,and regulate the desertification problem in the pastoral transitional zone.%土地沙漠化是当今世界最为严峻的生态环境问题之一.沙漠化逆转作为其反向转化过程,存在一定的脆弱性和不稳定性,即沙漠化逆转趋势减弱或反向发展的倾向.社会-生态系统理念是当今世界生态系统分析的新思路,从该视角界定沙漠化逆转过程的脆弱性概念,选取Driving-Pressure-Status-Impact-Response (DPSIR)分析框架,以农牧交错带典型沙漠化逆转区宁夏盐池县为案例,针对

  14. The semi-simple zeta function of quaternionic Shimura varieties

    CERN Document Server

    Reimann, Harry

    1997-01-01

    This monograph is concerned with the Shimura variety attached to a quaternion algebra over a totally real number field. For any place of good (or moderately bad) reduction, the corresponding (semi-simple) local zeta function is expressed in terms of (semi-simple) local L-functions attached to automorphic representations. In an appendix a conjecture of Langlands and Rapoport on the reduction of a Shimura variety in a very general case is restated in a slightly stronger form. The reader is expected to be familiar with the basic concepts of algebraic geometry, algebraic number theory and the theory of automorphic representation.

  15. Energy policies in the European Union. Germany's ecological tax reform

    International Nuclear Information System (INIS)

    Welfens, P.J.J.; Jungmittag, A.; Meyer, B.; Jasinski, P.

    2001-01-01

    The chapters discuss the following aspects: 1. Energy policy as a strategic element of economic policy in dynamic open economies. 2. Phasing out nuclear energy and core elements of sustainable energy strategy. 3. Ecological tax reform: Theory, modified double dividend and international aspects. 4. The policy framework in Europe and Germany. 5. Optimal ecological tax reform: Options and recommendations for an EU-action plan. 6. Conclusions. (orig./CB)

  16. Neither nature nor environment: Systemic operationalism and ecologism

    International Nuclear Information System (INIS)

    Gomez E, Luis F

    2009-01-01

    Nature is a complex concept that some critics have found as one of the roots of the current crisis of orthodox modernity. Because of this, we think ecologism should develop a theory where it does not play a pivotal role. Here, we propose systemic operationalism as a theoretical basis for ecologism since it seems to meet this requirement without having to replace it with terms such as environment which appears to keep some of the problems critics see in the concept of nature.

  17. Analysis of ecological environment impact of coal exploitation and utilization

    Science.gov (United States)

    Zhang, Baoliu; Luo, Hong; Lv, Lianhong; Wang, Jian; Zhang, Baoshi

    2018-02-01

    Based on the theory of life cycle assessment, the ecological and environmental impacts of coal mining, processing, utilization and transportation will be analyzed, with analysing the status of china’s coal exploitation and utilization as the basis, it will find out the ecological and environmental impact in the development and utilization of coal, mainly consist of ecological impact including land damage, water resource destructionand biodiversity loss, etc., while the environmental impact include air, water, solid waste pollutions. Finally with a summary of the ecological and environmental problems, to propose solutionsand countermeasures to promote the rational development and consumption of coal, as well as to reduce the impact of coal production and consumption on the ecological environment, finally to achieve the coordinated development of energy and the environment.

  18. When mechanism matters: Bayesian forecasting using models of ecological diffusion

    Science.gov (United States)

    Hefley, Trevor J.; Hooten, Mevin B.; Russell, Robin E.; Walsh, Daniel P.; Powell, James A.

    2017-01-01

    Ecological diffusion is a theory that can be used to understand and forecast spatio-temporal processes such as dispersal, invasion, and the spread of disease. Hierarchical Bayesian modelling provides a framework to make statistical inference and probabilistic forecasts, using mechanistic ecological models. To illustrate, we show how hierarchical Bayesian models of ecological diffusion can be implemented for large data sets that are distributed densely across space and time. The hierarchical Bayesian approach is used to understand and forecast the growth and geographic spread in the prevalence of chronic wasting disease in white-tailed deer (Odocoileus virginianus). We compare statistical inference and forecasts from our hierarchical Bayesian model to phenomenological regression-based methods that are commonly used to analyse spatial occurrence data. The mechanistic statistical model based on ecological diffusion led to important ecological insights, obviated a commonly ignored type of collinearity, and was the most accurate method for forecasting.

  19. Management applications of discontinuity theory

    Science.gov (United States)

    Angeler, David G.; Allen, Craig R.; Barichievy, Chris; Eason, Tarsha; Garmestani, Ahjond S.; Graham, Nicholas A.J.; Granholm, Dean; Gunderson, Lance H.; Knutson, Melinda; Nash, Kirsty L.; Nelson, R. John; Nystrom, Magnus; Spanbauer, Trisha; Stow, Craig A.; Sundstrom, Shana M.

    2015-01-01

    Human impacts on the environment are multifaceted and can occur across distinct spatiotemporal scales. Ecological responses to environmental change are therefore difficult to predict, and entail large degrees of uncertainty. Such uncertainty requires robust tools for management to sustain ecosystem goods and services and maintain resilient ecosystems.We propose an approach based on discontinuity theory that accounts for patterns and processes at distinct spatial and temporal scales, an inherent property of ecological systems. Discontinuity theory has not been applied in natural resource management and could therefore improve ecosystem management because it explicitly accounts for ecological complexity.Synthesis and applications. We highlight the application of discontinuity approaches for meeting management goals. Specifically, discontinuity approaches have significant potential to measure and thus understand the resilience of ecosystems, to objectively identify critical scales of space and time in ecological systems at which human impact might be most severe, to provide warning indicators of regime change, to help predict and understand biological invasions and extinctions and to focus monitoring efforts. Discontinuity theory can complement current approaches, providing a broader paradigm for ecological management and conservation.

  20. A Policy Analysis Perspective on Ecological Restoration

    Directory of Open Access Journals (Sweden)

    Susan Baker

    2013-06-01

    Full Text Available Using a simple stages model of the policy process, we explore the politics of ecological restoration using an array of examples drawn across sector, different size and scale, and from different countries. A policy analysis perspective reveals how, at both the program and project levels, ecological restoration operates within a complex and dynamic interplay between technical decision making, ideologies, and interest politics. Viewed through the stages model, restoration policy involves negotiating nature across stages in the policy making process, including agenda setting, policy formulation, implementation, and evaluation. The stages model is a useful heuristic devise; however, this linear model assumes that policy makers approach the issue rationally. In practice, ecological restoration policy takes place in the context of different distributions of power between the various public and private actors involved at the different stages of restoration policy making. This allows us to reiterate the point that ecological restoration is best seen not only as a technical task but as a social and political project.

  1. How Facilitation May Interfere with Ecological Speciation

    Directory of Open Access Journals (Sweden)

    P. Liancourt

    2012-01-01

    Full Text Available Compared to the vast literature linking competitive interactions and speciation, attempts to understand the role of facilitation for evolutionary diversification remain scarce. Yet, community ecologists now recognize the importance of positive interactions within plant communities. Here, we examine how facilitation may interfere with the mechanisms of ecological speciation. We argue that facilitation is likely to (1 maintain gene flow among incipient species by enabling cooccurrence of adapted and maladapted forms in marginal habitats and (2 increase fitness of introgressed forms and limit reinforcement in secondary contact zones. Alternatively, we present how facilitation may favour colonization of marginal habitats and thus enhance local adaptation and ecological speciation. Therefore, facilitation may impede or pave the way for ecological speciation. Using a simple spatially and genetically explicit modelling framework, we illustrate and propose some first testable ideas about how, when, and where facilitation may act as a cohesive force for ecological speciation. These hypotheses and the modelling framework proposed should stimulate further empirical and theoretical research examining the role of both competitive and positive interactions in the formation of incipient species.

  2. Combinatorial structures to modeling simple games and applications

    Science.gov (United States)

    Molinero, Xavier

    2017-09-01

    We connect three different topics: combinatorial structures, game theory and chemistry. In particular, we establish the bases to represent some simple games, defined as influence games, and molecules, defined from atoms, by using combinatorial structures. First, we characterize simple games as influence games using influence graphs. It let us to modeling simple games as combinatorial structures (from the viewpoint of structures or graphs). Second, we formally define molecules as combinations of atoms. It let us to modeling molecules as combinatorial structures (from the viewpoint of combinations). It is open to generate such combinatorial structures using some specific techniques as genetic algorithms, (meta-)heuristics algorithms and parallel programming, among others.

  3. Waltz's Theory of Theory

    DEFF Research Database (Denmark)

    Wæver, Ole

    2009-01-01

    -empiricism and anti-positivism of his position. Followers and critics alike have treated Waltzian neorealism as if it was at bottom a formal proposition about cause-effect relations. The extreme case of Waltz being so victorious in the discipline, and yet being consistently mis-interpreted on the question of theory......, shows the power of a dominant philosophy of science in US IR, and thus the challenge facing any ambitious theorising. The article suggests a possible movement of fronts away from the ‘fourth debate' between rationalism and reflectivism towards one of theory against empiricism. To help this new agenda...

  4. Ecological suicide in microbes.

    Science.gov (United States)

    Ratzke, Christoph; Denk, Jonas; Gore, Jeff

    2018-05-01

    The growth and survival of organisms often depend on interactions between them. In many cases, these interactions are positive and caused by a cooperative modification of the environment. Examples are the cooperative breakdown of complex nutrients in microbes or the construction of elaborate architectures in social insects, in which the individual profits from the collective actions of her peers. However, organisms can similarly display negative interactions by changing the environment in ways that are detrimental for them, for example by resource depletion or the production of toxic byproducts. Here we find an extreme type of negative interactions, in which Paenibacillus sp. bacteria modify the environmental pH to such a degree that it leads to a rapid extinction of the whole population, a phenomenon that we call ecological suicide. Modification of the pH is more pronounced at higher population densities, and thus ecological suicide is more likely to occur with increasing bacterial density. Correspondingly, promoting bacterial growth can drive populations extinct whereas inhibiting bacterial growth by the addition of harmful substances-such as antibiotics-can rescue them. Moreover, ecological suicide can cause oscillatory dynamics, even in single-species populations. We found ecological suicide in a wide variety of microbes, suggesting that it could have an important role in microbial ecology and evolution.

  5. Marx, Engels and Ecology

    Directory of Open Access Journals (Sweden)

    Michael Löwy

    2017-11-01

    Full Text Available This is a brief survey of Marx and Engels’ views on ecology, from the viewpoint of their relevance for 21th Century ecosocialism. While there are some serious limitations in the way both consider the “development of productive forces”, there are powerfull insights in their discussion of the destructive consequences of capitalist expansion for the environment - an expansion that generates a disastrous metabolic rift in the exchanges between human societies and nature. Some ecological Marxists distinguish between “first stage ecosocialists” - who believe that Marx analyses on ecological issues are too incomplete and dated to be of real relevance today - and “second stage ecosocialists” that emphasize the contemporary methodological significance of Marx’s ecological critique of capitalism. This paper tries to argue for a third position (which probably could be accepted by several people of the two groups above: Marx and Engels discussion on ecological issues is incomplete and dated, but inspite these shortcomings, it has real relevance and methodological significance today.

  6. The ecological century

    Energy Technology Data Exchange (ETDEWEB)

    Worthington, E. B.

    1981-01-01

    This essay attempts to reconstruct the evolution of Ecology as the scientific basis for environmental conservation and human progress, as seen through the eyes of a biologist who has exercised that science during a number of tasks in various parts of the world over most of the twentieth century. From its beginnings in evolutionary thinking during the nineteenth century, ecology emerged from natural history at the beginning of the twentieth. At first the running was made by botanists; but this was soon followed by zoologists, who dealt with more mobile communities. The first quarter-century was mainly exploratory; the second was mainly descriptive (although biological exploration was still dominant in the tropics). The third quarter saw ecology developing into an experimental science, and, as the environmental revolution got into its stride, ecology became organized both nationally and internationally. Although the term is now often misused and sometimes misunderstood by laymen, the last quarter-century is seeing the wide application of ecology in environmental and human affairs, and this gives some assurance that the twenty-first century will not become one of chaos.

  7. REWRITING ECOLOGICAL SUCCESSION HISTORY: DID CARRION ECOLOGISTS GET THERE FIRST?

    Science.gov (United States)

    Michaud, Jean-Philippe; Schoenly, Kenneth G; Moreau, Gaétan

    2015-03-01

    Ecological succession is arguably the most enduring contribution of plant ecologists and its origins have never been contested. However, we show that French entomologist Pierre Mégnin, while collaborating with medical examiners in the late 1800s, advanced the first formal definition and testable mechanism of ecological succession. This discovery gave birth to the twin disciplines of carrion ecology and forensic entomology. As a novel case of multiple independent discovery, we chronicle how the disciplines of plant and carrion ecology (including forensic entomology) accumulated strikingly similar parallel histories and contributions. In the 1900s, the two groups diverged in methodology and purpose, with carrion ecologists and forensic entomologists focusing mostly on case reports and observational studies instead of hypothesis testing. Momentum is currently growing, however, to develop the ecological framework of forensic entomology and advance carrion ecology theory. Researchers are recognizing the potential of carcasses as subjects for testing not only succession mechanisms (without assuming space-for-time substitution), but also aggregation and coexistence models, diversity-ecosystem function relationships, and the dynamics of pulsed resources. By comparing the contributions of plant and carrion ecologists, we hope to stimulate future crossover research that leads to a general theory of ecological succession.

  8. Gauge boson mass without a Higgs field: a simple model

    International Nuclear Information System (INIS)

    Nicholson, A.F.; Kennedy, D.C.

    1997-02-01

    A simple, anomaly-free chiral gauge theory can be perturbatively quantized and renormalized in such a way as to generate fermion and gauge boson masses. This development exploits certain freedoms inherent in choosing the unperturbed Lagrangian and in the renormalization procedure. Apart from its intrinsic interest, such a mechanism might be employed in electroweak gauge theory to generate fermion and gauge boson masses without a Higgs sector. 38 refs

  9. Excitation of simple atoms by slow magnetic monopoles

    International Nuclear Information System (INIS)

    Kroll, N.M.; Parke, S.J.; Ganapathi, V.; Drell, S.D.

    1984-01-01

    We present a theory of excitation of simple atoms by slow moving massive monopoles. Previously presented results for a monopole of Dirac strength on hydrogen and helium are reviewed. The hydrogen theory is extended to include arbitrary integral multiples of the Dirac pole strength. The excitation of helium by double strength poles and by dyons is also discussed. It is concluded that a helium proportional counter is a reliable and effective detector for monopoles of arbitrary strength, and for negatively charged dyons

  10. Algebraic and stochastic coding theory

    CERN Document Server

    Kythe, Dave K

    2012-01-01

    Using a simple yet rigorous approach, Algebraic and Stochastic Coding Theory makes the subject of coding theory easy to understand for readers with a thorough knowledge of digital arithmetic, Boolean and modern algebra, and probability theory. It explains the underlying principles of coding theory and offers a clear, detailed description of each code. More advanced readers will appreciate its coverage of recent developments in coding theory and stochastic processes. After a brief review of coding history and Boolean algebra, the book introduces linear codes, including Hamming and Golay codes.

  11. ECOLOGICAL ECONOMICS VS ECONOMIC(AL ECOLOGY

    Directory of Open Access Journals (Sweden)

    G. Kharlamova

    2015-10-01

    Full Text Available Currently world faces the dilemma – ecological economy or economic(al ecology. The researchers produce hundreds of surveys on the topic. However the analyses of recent most cited simulations had shown the diversity of results. Thus, for some states the Kuznets environmental curve has place, for others – no. Same could be said about different years for the same state. It provokes the necessity of drawing new group analyses to reveal the tendencies and relationships between economic and environmental factors. Most flexible and mirror factor of environmental sustainability is the volume of CO2 emissions. The econometric analysis was used for detecting the economic impact on this indicator at the global level and in the spectra of group of states depending on their income. The hypothesis of the existence of environmental Kuznets curve for the analysed data is rejected. Real GDP per capita impact on carbon dioxide emissions is considered only at the global level. The impact of openness of the economy is weak. Rejection happened also to the hypothesis that for the developed countries there is a reverse dependence between the environmental pollution and economic openness. Indicator “energy consumption per capita” impacts on greenhouse gas emissions only in countries with high income. Whereby it should be noted that the more developed a country is, the more elastic is this influence. These results have a potential usage for environmental policy regulation and climate strategy.

  12. Keeping it simple: flowering plants tend to retain, and revert to, simple leaves.

    Science.gov (United States)

    Geeta, R; Dávalos, Liliana M; Levy, André; Bohs, Lynn; Lavin, Mathew; Mummenhoff, Klaus; Sinha, Neelima; Wojciechowski, Martin F

    2012-01-01

    • A wide range of factors (developmental, physiological, ecological) with unpredictable interactions control variation in leaf form. Here, we examined the distribution of leaf morphologies (simple and complex forms) across angiosperms in a phylogenetic context to detect patterns in the directions of changes in leaf shape. • Seven datasets (diverse angiosperms and six nested clades, Sapindales, Apiales, Papaveraceae, Fabaceae, Lepidium, Solanum) were analysed using maximum likelihood and parsimony methods to estimate asymmetries in rates of change among character states. • Simple leaves are most frequent among angiosperm lineages today, were inferred to be ancestral in angiosperms and tended to be retained in evolution (stasis). Complex leaves slowly originated ('gains') and quickly reverted to simple leaves ('losses') multiple times, with a significantly greater rate of losses than gains. Lobed leaves may be a labile intermediate step between different forms. The nested clades showed mixed trends; Solanum, like the angiosperms in general, had higher rates of losses than gains, but the other clades had higher rates of gains than losses. • The angiosperm-wide pattern could be taken as a null model to test leaf evolution patterns in particular clades, in which patterns of variation suggest clade-specific processes that have yet to be investigated fully. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  13. Combining statistical inference and decisions in ecology

    Science.gov (United States)

    Williams, Perry J.; Hooten, Mevin B.

    2016-01-01

    Statistical decision theory (SDT) is a sub-field of decision theory that formally incorporates statistical investigation into a decision-theoretic framework to account for uncertainties in a decision problem. SDT provides a unifying analysis of three types of information: statistical results from a data set, knowledge of the consequences of potential choices (i.e., loss), and prior beliefs about a system. SDT links the theoretical development of a large body of statistical methods including point estimation, hypothesis testing, and confidence interval estimation. The theory and application of SDT have mainly been developed and published in the fields of mathematics, statistics, operations research, and other decision sciences, but have had limited exposure in ecology. Thus, we provide an introduction to SDT for ecologists and describe its utility for linking the conventionally separate tasks of statistical investigation and decision making in a single framework. We describe the basic framework of both Bayesian and frequentist SDT, its traditional use in statistics, and discuss its application to decision problems that occur in ecology. We demonstrate SDT with two types of decisions: Bayesian point estimation, and an applied management problem of selecting a prescribed fire rotation for managing a grassland bird species. Central to SDT, and decision theory in general, are loss functions. Thus, we also provide basic guidance and references for constructing loss functions for an SDT problem.

  14. Mathematical models of ecology and evolution

    DEFF Research Database (Denmark)

    Zhang, Lai

    2012-01-01

    -history processes: net-assimilation mechanism of 􀀀rule and net-reproduction mechanism of size dependence using a simple model comprising a size-structured consumer Daphina and an unstructured resource alge. It is found that in contrast to the former mechanism, the latter tends to destabilize population...... dynamics but as a trade-o promotes species survival by shortening juvenile delay between birth and the onset of reproduction. Paper II compares the size-spectrum and food-web representations of communities using two traits (body size and habitat location) based unstructured population model of Lotka......) based size-structured population model, that is, interference in foraging, maintenance, survival, and recruitment. Their impacts on the ecology and evolution of size-structured populations and communities are explored. Ecologically, interference aects population demographic properties either negatively...

  15. Optimizing sampling approaches along ecological gradients

    DEFF Research Database (Denmark)

    Schweiger, Andreas; Irl, Severin D. H.; Steinbauer, Manuel

    2016-01-01

    1. Natural scientists and especially ecologists use manipulative experiments or field observations along gradients to differentiate patterns driven by processes from those caused by random noise. A well-conceived sampling design is essential for identifying, analysing and reporting underlying...... patterns in a statistically solid and reproducible manner, given the normal restrictions in labour, time and money. However, a technical guideline about an adequate sampling design to maximize prediction success under restricted resources is lacking. This study aims at developing such a solid...... and reproducible guideline for sampling along gradients in all fields of ecology and science in general. 2. We conducted simulations with artificial data for five common response types known in ecology, each represented by a simple function (no response, linear, exponential, symmetric unimodal and asymmetric...

  16. Ecological impact assessment

    International Nuclear Information System (INIS)

    Thomas, J.M.; Eberhardt, L.L.

    1975-01-01

    Quantitative problems in accomplishing ecological impact assessment with particular reference to defining population effects are discussed with some comments on the two approaches most commonly used, e.g., the experimental and simulation models. Some alternatives are suggested because both methods will probably fail to detect real population effects mostly due to poor understanding of ecosystems or because of the limitations inherent in field census methods. Most judgments of ecological impact are not quantitatively defensible but are qualitative, subjective, or political in nature. An examination of aggregates of data from various nuclear power plant sites may be one way to obtain enough replication to judge ecological impact. Thus, currently available data from such studies as well as appropriate demographic, vegetation, census, and bibliographic material could offer an interesting challenge to computer professionals if such an undertaking were contemplated. Present research programs at PNL and computer involvement are described. Future possibilities and directions are discussed. (U.S.)

  17. Numerical ecology with R

    CERN Document Server

    Borcard, Daniel; Legendre, Pierre

    2018-01-01

    This new edition of Numerical Ecology with R guides readers through an applied exploration of the major methods of multivariate data analysis, as seen through the eyes of three ecologists. It provides a bridge between a textbook of numerical ecology and the implementation of this discipline in the R language. The book begins by examining some exploratory approaches. It proceeds logically with the construction of the key building blocks of most methods, i.e. association measures and matrices, and then submits example data to three families of approaches: clustering, ordination and canonical ordination. The last two chapters make use of these methods to explore important and contemporary issues in ecology: the analysis of spatial structures and of community diversity. The aims of methods thus range from descriptive to explanatory and predictive and encompass a wide variety of approaches that should provide readers with an extensive toolbox that can address a wide palette of questions arising in contemporary mul...

  18. Biodiversity in Benthic Ecology

    DEFF Research Database (Denmark)

    Friberg, Nikolai; Carl, J. D.

    Foreword: This proceeding is based on a set of papers presented at the second Nordic Benthological Meeting held in Silkeborg, November 13-14, 1997. The main theme of the meeting was biodiversity in benthic ecology and the majority of contributions touch on this subject. In addition, the proceeding...... contains papers which cover other themes thus continuing with the spirit of the meetings in the Nordic Benthological Society (NORBS) by being an open forum for exchanging knowledge on all aspects of benthic ecology. Overall, we feel the proceeding contains a wide selection of very interesting papers...... representing the state-of-the-art of benthic ecology research within, and to a lesser degree, outside the Nordic countries. We wish to thank all the authors for their inspirational contributions to the proceeding, but we feel that a special thanks is due to the invited speakers for their readiness to produce...

  19. Application of ecological mapping

    International Nuclear Information System (INIS)

    Sherk, J.A.

    1982-01-01

    The US Fish and Wildlife Service has initiated the production of a comprehensive ecological inventory map series for use as a major new planning tool. Important species data along with special land use designations are displayed on 1:250,000 scale topographic base maps. Sets of maps have been published for the Atlantic and Pacific coastal areas of the United States. Preparation of a map set for the Gulf of Mexico is underway at the present time. Potential application of ecological inventory map series information to a typical land disposal facility could occur during the narrowing of the number of possible disposal sites, the design of potential disposal site studies of ecological resources, the preparation of the environmental report, and the regulatory review of license applications. 3 figures, 3 tables

  20. Ecological Perspectives in HCI

    DEFF Research Database (Denmark)

    Blevis, Eli; Bødker, Susanne; Flach, John

    The aim of the workshop is to provide a forum for researchers and practitioners to discuss the present and future of ecological perspectives in HCI. The participants will reflect on the current uses and interpretations of “ecology” and related concepts in the field. The workshop will assess the p...... the potential of ecological perspectives in HCI for supporting rich and meaningful analysis, as well as innovative design, of interactive technologies in real-life contexts......The aim of the workshop is to provide a forum for researchers and practitioners to discuss the present and future of ecological perspectives in HCI. The participants will reflect on the current uses and interpretations of “ecology” and related concepts in the field. The workshop will assess...